[Federal Register Volume 79, Number 224 (Thursday, November 20, 2014)]
[Rules and Regulations]
[Pages 69191-69310]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-27109]
[[Page 69191]]
Vol. 79
Thursday,
No. 224
November 20, 2014
Part II
Department of the Interior
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Fish and Wildlife Service
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50 CFR Part 17
Endangered and Threatened Wildlife and Plants; Threatened Status for
Gunnison Sage-Grouse; Final Rule
Federal Register / Vol. 79 , No. 224 / Thursday, November 20, 2014 /
Rules and Regulations
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R6-ES-2012-0108; 4500030114]
RIN 1018-AZ20
Endangered and Threatened Wildlife and Plants; Threatened Status
for Gunnison Sage-Grouse
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), determine
threatened species status under the Endangered Species Act of 1973, as
amended (Act), for the Gunnison sage-grouse (Centrocercus minimus), a
bird species from southwestern Colorado and southeastern Utah. The
effect of this regulation will be to add the Gunnison sage-grouse to
the List of Endangered and Threatened Wildlife.
DATES: This rule is effective December 22, 2014.
ADDRESSES: This final rule is available on the internet at http://www.regulations.gov and http://www.fws.gov/mountain-prairie/species/birds/gunnisonsagegrouse. Comments and materials we received, as well
as supporting documentation we used in preparing this rule, are
available for public inspection at http://www.regulations.gov. All of
the comments, materials, and documentation that we considered in this
rulemaking are available by appointment, during normal business hours
at: U.S. Fish and Wildlife Service, Western Colorado Field Office, 445
West Gunnison Avenue, Suite 240, Grand Junction, CO 81501-5720;
telephone 970-243-2778.
FOR FURTHER INFORMATION CONTACT: Susan Linner, Field Supervisor, U.S.
Fish and Wildlife Service, Colorado Ecological Services Office, 134
Union Blvd., Suite 670, P.O. Box 25486 DFC, Denver, CO 80225; telephone
303-236-4774. Persons who use a telecommunications device for the deaf
(TDD) may call the Federal Information Relay Service (FIRS) at 800-877-
8339.
SUPPLEMENTARY INFORMATION:
Executive Summary
Why we need to publish a rule. Under the Endangered Species Act a
species may warrant protection through listing if it is endangered or
threatened as those terms are defined in the Act. Listing a species as
an endangered or threatened species can only be completed by issuing a
rule. In this case, we are required by a judicially approved settlement
agreement to make a final determination regarding the Gunnison sage-
grouse by no later than November 12, 2014. Elsewhere in today's Federal
Register we finalize the designation of critical habitat for the
species.
This rule will finalize the listing of the Gunnison sage-grouse
(Centrocercus minimus) as a threatened species.
The basis for our action. Under the Endangered Species Act, we can
determine that a species is an endangered or threatened species based
on any of five factors: (A) The present or threatened destruction,
modification, or curtailment of its habitat or range; (B)
Overutilization for commercial, recreational, scientific, or
educational purposes; (C) Disease or predation; (D) The inadequacy of
existing regulatory mechanisms; or (E) Other natural or manmade factors
affecting its continued existence.
As described in detail below, we have determined that the most
substantial threats to Gunnison sage-grouse currently and in the future
include habitat decline due to human disturbance (Factor A), small
population size and structure (Factor E), drought (Factor E), climate
change (Factor A), and disease (Factor C). Other threats that are
impacting Gunnison sage-grouse to a lesser degree or in localized areas
include grazing practices inconsistent with local ecological
conditions, fences, invasive plants, fire, mineral development,
pi[ntilde]on-juniper encroachment, large-scale water development
(Factor A); predation (Factor C), primarily in association with
anthropogenic disturbance and habitat decline due to human disturbance
(Factor A); and recreation (Factor E). As described in Factor D below,
some existing regulatory mechanisms are in place to conserve Gunnison
sage-grouse, but individually or collectively they do not fully address
the substantial threats faced by the species, particularly habitat
decline, small population size and structure, drought, climate change,
and disease. The threats listed above are also acting cumulatively,
contributing to the challenges faced by Gunnison sage-grouse now and
into the future.
Multiple partners, including private citizens, nongovernmental
organizations, and Tribal, State, and Federal agencies, are engaged in
conservation efforts across the range of Gunnison sage-grouse. Numerous
conservation actions have been implemented or are planned for Gunnison
sage-grouse, and these efforts have provided and will continue to
provide conservation benefit to the species. The Candidate Conservation
Agreement with Assurances for Gunnison sage-grouse (CCAA), Gunnison
Basin Candidate Conservation Agreement (CCA), conservation plans,
multi-county commitments, habitat improvement projects, and similar
non-regulatory conservation actions that address habitat-related
impacts and issues are described and evaluated under Factor A in this
rule. Federal, State, and local laws and regulations, conservation
easements, and other regulatory mechanisms are evaluated under Factor
D. Scientific research activities are described under Factor B and
throughout this rule where applicable. Also, conservation efforts are
described and evaluated as appropriate under relevant threat sections
throughout this rule.
Peer review and public comment. We sought comments on the proposed
rule from independent and qualified specialists to ensure that our
determination is based on scientifically sound data, assumptions, and
analyses. We invited these peer reviewers to comment on our listing
proposal. We also considered all comments and information received
during each public comment period.
Previous Federal Actions
Please refer to the proposed listing rule for the Gunnison sage-
grouse (78 FR 2486, January 11, 2013) for a detailed description of
previous Federal actions concerning this species. Federal actions that
have occurred since that publication are described below.
On January 11, 2013, we published a rule proposing to list the
Gunnison sage-grouse as endangered throughout its range (78 FR 2486),
and a proposed rule to designate 1.7 million acres of critical habitat
for the species (78 FR 2540). We opened a public comment period until
March 12, 2013, that was subsequently extended until April 2, 2013 (78
FR 15925, March 13, 2013).
On July 19, 2013, we announced that we were extending the final
rule deadline by 6 months, from September 30, 2013, to March 31, 2014;
and reopened the comment period until September 3, 2013 (78 FR 43123).
This extension served to solicit additional scientific information due
to scientific disagreement regarding the sufficiency and accuracy of
the available data relevant to our listing determinations for Gunnison
sage-grouse.
On September 19, 2013, we announced the availability of a draft
economic analysis and draft environmental assessment for our proposal
to designate critical habitat for
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Gunnison sage-grouse, and reopened the public comment period on those
subjects and the proposed listing and critical habitat rules until
October 19, 2013. We also announced two planned public informational
sessions and public hearings for the proposed rules (78 FR 57604).
On November 4, 2013, we reopened the public comment period on the
proposed rules until December 2, 2013, and announced the rescheduling
of three public information sessions and public hearings that were
postponed due to the lapse in government appropriations in October 2013
(78 FR 65936).
Public information sessions and public hearings were held in
Gunnison, Colorado, on November 19, 2013; Montrose, Colorado, on
November 20, 2013; and Monticello, Utah, on November 21, 2013.
In a press release on February 12, 2014, available on our Web page
at http://www.fws.gov/mountain-prairie/species/birds/gunnisonsagegrouse/, we announced a 6-week extension, to May 12, 2014,
for our final decision on our proposed listing and critical habitat
rules. This extension was granted by the Court due to delays caused by
the lapse in government appropriations in October 2013, and the
resulting need to reopen a public comment period and reschedule public
hearings.
In a press release on May 6, 2014, available on our Web page at
http://www.fws.gov/mountain-prairie/species/birds/gunnisonsagegrouse/,
we announced a 6-month extension, to November 12, 2014, for our final
decision to list Gunnison sage-grouse under the Act. This extension was
granted by the Court to provide the Service with additional time to
complete a final listing determination for the Gunnison sage-grouse,
and if listed, a final critical habitat designation. In the event the
Service decided to list the species as threatened, the court order also
allowed for the Service to publish a proposed rule under section 4(d)
of the Act (which are only available for threatened species) and
finalize it with the final listing determination on November 12, if
appropriate. We decided not to propose and finalize a 4(d) rule for the
Gunnison sage-grouse at this time, but continue to evaluate the
potential for issuing a section 4(d) rule in the future to tailor the
take prohibitions of the Act to those necessary and advisable to
provide for the conservation of the Gunnison sage-grouse.
Elsewhere in today's Federal Register, we finalize the designation
of critical habitat for the species.
Background
Gunnison sage-grouse and greater sage-grouse (a similar, closely
related species) have similar life histories and habitat requirements
(Young 1994, p. 44). In this final rule, we use scientific information
specific to the Gunnison sage-grouse where available but apply
scientific management principles and scientific information for greater
sage-grouse that are relevant to Gunnison sage-grouse threats,
conservation needs, and strategies--a practice followed by the wildlife
and land management agencies that have responsibility for management of
both species and their habitat. Throughout this rule, we use sage-
grouse in reference to both Gunnison and greater sage-grouse whenever
the scientific data and information is relevant to both species.
Species Information
A detailed summary of Gunnison sage-grouse taxonomy, the species
description, historical distribution, habitat, and life-history
characteristics can be found in the 12-month finding published
September 28, 2010 (75 FR 59804). More recent scientific information
relevant to the species and our evaluation of the species is included
throughout this final rule.
Current Distribution and Population Estimates and Trends
Gunnison sage-grouse currently occur in seven populations in
Colorado and Utah, occupying 3,795 square kilometers (km\2\) (1,511
square miles [mi\2\]) (Gunnison Sage-grouse Rangewide Steering
Committee) [GSRSC] 2005, pp. 36-37; CDOW 2009a, p. 1). The seven
populations are Gunnison Basin, San Miguel Basin, Monticello-Dove
Creek, Pi[ntilde]on Mesa, Crawford, Cerro Summit-Cimarron-Sims Mesa,
and Poncha Pass (Figure 1). A summary of land ownership and recent
population estimates among these seven populations is presented in
Table 1, and Figures 2 and 3, respectively. The following information
and Figures 2 and 3 are based on lek count data (systematic counts of
male sage-grouse attendance at traditional breeding sites) and
associated population estimates from Colorado Parks and Wildlife (CPW)
and the Utah Division of Wildlife Resources (UDWR) for the period 1996-
2014 (CDOW 2010a, p. 2; CPW 2012a, pp. 1-4; CPW 2013a, p. 1; CPW 2014d,
p. 1).
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[GRAPHIC] [TIFF OMITTED] TR20NO14.000
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Table 1--Percent Surface Ownership of Gunnison Sage-Grouse Occupied \a\ Habitat
[GSRSC \b\ 2005, pp. D-3-D-6; CDOW \c\ 2009a, p. 1; CPW 2013e, spatial data]
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Gunnison sage-grouse occupied habitat management and ownership
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BLM \d\ NPS \e\ USFS \f\ CPW CO SLB State of Private
Population Hectares Acres ---------------------------------------- \g\ UT ---------
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% % % % % % %
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Gunnison Basin............................................ 239,641 592,168 51 2 14 2 <1 0 \i\ 30
San Miguel Basin.......................................... 41,177 101,750 \g\ 35 0 1 11 \g\ 3 0 \h\ 49
Monticello-Dove Creek (Combined).......................... 45,544 112,543 7 0 0 3 0 <1 90
Dove Creek............................................ 16,949 41,881 13 0 0 6 0 0 82
Monticello............................................ 28,595 70,661 5 0 0 0 0 1 94
Pi[ntilde]on Mesa......................................... 18,080 44,678 28 0 2 0 0 0 70
Cerro Summit-Cimarron-Sims Mesa........................... 15,039 37,161 13 <1 0 11 0 0 76
Crawford.................................................. 14,170 35,015 63 12 0 0 0 0 24
Poncha Pass............................................... 11,229 27,747 48 0 20 0 4 0 28
Rangewide................................................. 384,880 951,061 42 2 10 3 <1 <1 43
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\a\ Occupied Gunnison sage-grouse habitat is defined as areas of suitable habitat known to be used by Gunnison sage-grouse within the last 10 years from
the date of mapping, and areas of suitable habitat contiguous with areas of known use, which have no barriers to grouse movement from known use areas
(GSRSC 2005, p. 54; CPW 2013e, spatial data).
\b\ Gunnison Sage-grouse Rangewide Steering Committee.
\c\ Colorado Parks and Wildlife.
\d\ Bureau of Land Management.
\e\ National Park Service.
\f\ United States Forest Service.
\g\ State Land Board.
\h\ Estimates reported in San Miguel Basin Gunnison Sage-grouse Conservation Plan (San Miguel Basin Gunnison Sage-grouse Working Group (SMBGSWG) 2009,
p. 28) vary by 2 percent in these categories from those reported here. We consider these differences insignificant.
\i\ Includes approximately 12,000 ac of land on Pinecrest Ranch, west of Gunnison, Colorado. This is restricted fee status land held in private
ownership by the Ute Mountain Ute Tribe.
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[GRAPHIC] [TIFF OMITTED] TR20NO14.001
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[GRAPHIC] [TIFF OMITTED] TR20NO14.002
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Lek count data are the primary means of estimating and monitoring
Gunnison sage-grouse populations. However, sage-grouse populations can
fluctuate widely on an annual basis, and there are concerns about the
statistical reliability of population estimates based on lek counts
(CDOW 2009b, pp. 1-3). Stiver et al. (2008, p. 474) concluded that lek
counts likely underestimate population size. Another study (Davis 2012,
p. 136) indicated that, based on demographic data, lek count indices
overestimate population size. Although lek count data are available
from as early as the 1950s for some populations, lek count protocols
were first standardized and implemented in 1996 (GSRSC 2005, p. 46).
Prior to 1996, lek count data are highly variable and uncertain, and
are not directly comparable to recent population data (Braun 1998, p.
3; Davis 2012, pp. 139, 143). Therefore, for the purposes of evaluating
current population sizes and trends, the analysis in this rule is
focused on lek count data from 1996 to 2014. We also consider other
available scientific information such as demographic data and
population viability analyses (see Factor E). Historical distribution
and population information is discussed under Factor A below.
The Gunnison Basin is the largest population (approximately 3,978
birds) and, while showing variation over the period of record,
including drought cycles and harsh winters, has been relatively stable,
based on lek count estimates (but see further discussion below and in
the Factor E analysis). The Gunnison Basin population is the primary
influence on the rangewide population size of Gunnison sage-grouse (see
Figure 2); thus, the significance of this population to the species'
survival and persistence is evident. The Gunnison Basin population area
includes approximately 239,600 ha (592,053 ac) of occupied habitat.
In contrast, the remaining six populations, or satellite
populations, are much smaller than the Gunnison Basin. All satellite
populations were generally in decline until 2010; however, increases in
several populations have been observed recently (Figure 3) and could be
a product of numerous factors including but not limited to population
cycles, translocation efforts, and increased access to leks. San Miguel
and Pi[ntilde]on Mesa are currently the largest of the satellite
populations, with 206 and 182 birds, respectively, in 2014. The
Monticello-Dove Creek populations currently have less than 100 birds
combined (74 and 24, respectively). The current (2014) population
estimates for the two smallest populations, Cerro Summit-Cimarron-Sims
Mesa and Poncha Pass, are 74 and 16, respectively (CPW 2014d, p. 1). A
count of zero birds at Poncha Pass in 2013 suggests that extirpation of
this population may have occurred, although 17 birds were translocated
there later that fall, and ten more in spring of 2014, with 16 known to
survive into summer 2014 (see Factor B, Scientific Research and Related
Conservation Efforts). The satellite population areas are much smaller
than the Gunnison Basin population area, all with less than 40,500
hectares (ha) (100,000 acres [ac]) of occupied habitat (Table 1) and,
with the exception of the San Miguel population, fewer than 40 males
counted on leks (CDOW 2009b, p. 5; CPW 2012a, p. 3; CPW 2013a, p. 1;
CPW 2014d, p. 1).
Lek count-based population estimates suggest some satellite
populations have increased slightly over the last several years.
However, lek count data spanning the last 19 years (1996 to 2014) as a
whole indicate that all the satellite populations were generally in
decline until 2010 (Figure 3). Several of the satellite populations
remain in decline and all remain at population size estimates that
indicate concern for their viability, ranging from 206 to 10 birds
(Figure 3). Furthermore, some of the recent increases in population
sizes can be attributed to translocation and survey efforts, rather
than an actual increase in the population. For example, the 2014
estimated population for Pi[ntilde]on Mesa was 182 birds (CPW 2014d, p.
1), much greater than the 2012 estimate of 54 birds. The population in
Crawford increased from 20 birds in 2010 to 157 in 2014. These
increases may be due in part to the translocation of 93 birds to the
Pi[ntilde]on Mesa population between the spring of 2010 and spring of
2013 and 73 birds to Crawford over the same period. (CPW 2014c,
entire), and two new leks found in 2012 on Pi[ntilde]on Mesa (CPW
2012a, pp. 2-3). The potential historical range of Gunnison sage-grouse
is discussed briefly below by population, and loss of historical range
is discussed under Factor A.
Gunnison Basin Population--The Gunnison Basin is an intermontane
(located between mountain ranges) basin that includes parts of Gunnison
and Saguache Counties, Colorado. The current Gunnison Basin population
is distributed across approximately 239,640 ha (592,168 ac) (Table 1),
surrounding the City of Gunnison. This population comprises
approximately 84 percent of the rangewide population and 62 percent of
occupied habitat for the species rangewide. Elevations in the area
occupied by Gunnison sage-grouse range from 2,300 to 2,900 meters (m)
(7,500 to 9,500 feet [ft]). Approximately 69 percent of the land area
occupied by Gunnison sage-grouse in this population is managed by
Federal agencies (67 percent) and CPW (2 percent), and the remaining 30
percent is primarily private lands, including approximately 12,000 ac
on Pinecrest Ranch owned by the Ute Mountain Ute Tribe under restricted
fee status. Wyoming big sagebrush (Artemisia tridentata ssp.
wyomingensis) and mountain big sagebrush (A. t. ssp. vaseyana) dominate
the upland vegetation, with highly variable growth form depending on
local site conditions.
In 1964, Gunnison County was one of five counties containing the
majority of all sage-grouse in Colorado. This was likely the case
before Euro-American settlement, around the turn of the century, as
well (Rogers 1964, pp. 13, 20). The 2014 population estimate for the
Gunnison Basin was 3,978 birds (CPW 2014d, p. 1). Population estimates
from 1996 to 2014 meet or exceed the population target of 3,000
breeding birds (based on a 10-year average) for the Gunnison Basin, as
set forth by the Gunnison Sage-grouse Rangewide Conservation Plan (RCP)
(CPW 2013a, p. 10; GSRSC 2005, p. 270). Based on available habitat and
other considerations, the RCP identified population targets as
attainable population sizes sufficient to conserve Gunnison sage-grouse
in each population (GSRSC 2005, p. 255). Approximately 45 percent of
leks in the Gunnison Basin occur on private land; and 55 percent are on
public land administered primarily by the BLM (GSRSC 2005, p. 75). Five
physiographic zones or divisions are recognized in the Gunnison Basin
population area for the purposes of monitoring and management actions
(CSGWG 1997, pp. 6-7).
San Miguel Basin Population-- The San Miguel Basin population
estimate in 2014 was 206 individuals (CPW 2014d, p. 1). Population
estimates from 1996 to 2014 are less than 50 percent of the population
target of 450 Gunnison sage-grouse (based on a 10-year average) for the
San Miguel Basin, as set forth by the RCP (CPW 2013a, p. 12; GSRSC
2005, p. 296). This population occurs in Montrose and San Miguel
Counties in Colorado, and comprises six small subpopulations (Dry Creek
Basin, Hamilton Mesa, Miramonte Reservoir, Gurley Reservoir, Beaver
Mesa, and Iron Springs) occupying approximately 41,177 ha (101,750 ac).
Gunnison sage-grouse use some of these areas year-round, while others
are used seasonally. Gunnison sage-grouse in the San Miguel Basin move
widely between the six
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subpopulation areas (Apa 2004, p. 29; Stiver and Gibson 2005, p. 12).
The area encompassed by this population is thought to have once served
as critical migration corridors between populations to the north
(Pi[ntilde]on Mesa) and northeast (Cerro Summit-Cimarron-Sims Mesa) and
to the west (Monticello-Dove Creek) (Oyler-McCance et al. 2005, pp.
635-636; SMBGSWG 2009, p. 9), but gene flow among these populations is
currently very low (Oyler-McCance et al. 2005, p. 635). Historically,
Gunnison sage-grouse occupied the majority of available big sagebrush
(Artemisia tridentata) plant communities in San Miguel and Montrose
Counties (Rogers 1964, pp. 22, 115).
Habitat conditions vary among the six subpopulation areas of the
San Miguel Basin population areas. The following discussion addresses
conditions among the subpopulations beginning in the west and moving
east. The majority of occupied acres in the San Miguel Basin population
(approximately 25,130 ha (62,100 ac) or 62 percent of the total
population area) occur in the Dry Creek Basin subpopulation (SMBGSWG
2009, p. 28). However, the Dry Creek Basin contains some of the poorest
quality habitat and the fewest individual Gunnison sage grouse numbers
in the San Miguel population (SMBGSWG 2009, pp. 28, 36). Sagebrush
habitat in the Dry Creek Basin area is patchily distributed. Where
irrigation is possible, private lands in the southeastern portion of
Dry Creek Basin are cultivated. Sagebrush habitat on private land has
been heavily thinned or removed entirely (GSRSC 2005, p. 96).
Elevations in the Hamilton Mesa subpopulation are approximately 610 m
(2,000 ft.) higher than in the Dry Creek Basin, resulting in more mesic
(moist) conditions. Agriculture is very limited on Hamilton Mesa, and
the majority of the vegetation consists of oakbrush (Quercus gambelii)
and sagebrush. Gunnison sage-grouse use the Hamilton Mesa area (1,940
ha (4,800 ac)) in the summer, but use of Hamilton Mesa during other
seasons is unknown.
Gunnison sage-grouse occupy approximately 4,700 ha (11,600 ac)
around Miramonte Reservoir (GSRSC 2005, p. 96). Sagebrush stands there
are generally contiguous with a mixed-grass and forb understory.
Occupied habitat at the Gurley Reservoir area (3,305 ha (7,500 ac)) is
negatively affected by human development. Farming attempts in the
Gurley Reservoir area in the early 20th century led to the removal of
much of the sagebrush, although agricultural activities are now
restricted primarily to the seasonally irrigated crops (hay meadows),
and sagebrush has reestablished in most of the failed pastures.
However, grazing pressure and competition from introduced grasses have
limited overall sagebrush representation (GSRSC 2005, pp. 96-97).
Sagebrush stands in the Iron Springs and Beaver Mesa areas (2,590 ha
and 3,560 ha (6,400 ac and 8,800 ac respectively)) are contiguous with
a mixed-grass understory. The Beaver Mesa area has numerous scattered
patches of oakbrush.
Monticello-Dove Creek Population--This population includes two
separate subpopulations of Gunnison sage-grouse, the Monticello and
Dove Creek subpopulations. Genetic data suggest these two
subpopulations could be considered one population (GSRSC 2005, p. 37),
though we are unaware of any current connectivity between the two. The
larger subpopulation is near the town of Monticello in San Juan County,
Utah. Gunnison sage-grouse in this subpopulation inhabit a broad
plateau on the northeastern side of the Abajo Mountains, with
fragmented patches of sagebrush interspersed with large grass pastures
and agricultural fields. In 1972, the estimated population size ranged
from 583 to 1,050 individuals; by 2002, the population size had
decreased, estimated at 178 to 308 individuals (UDWR 2011, p. 1). The
2013 and 2014 population estimates are 74 individuals (CPW 2013a, p. 1;
CPW 2014d, p. 1)). Gunnison sage-grouse currently occupy an estimated
28,595 ha (70,661 ac) in the Monticello area (GSRSC 2005, p. 81).
The Dove Creek subpopulation is located primarily in western
Dolores County, Colorado, north and west of Dove Creek, although a
small portion of occupied habitat extends north into San Miguel County.
The majority of sagebrush plant communities in Dolores and Montezuma
Counties within Colorado were historically used by Gunnison sage-grouse
(Rogers 1964, pp. 22, 112). Habitat north of Dove Creek is
characterized as mountain shrub habitat, dominated by oakbrush
interspersed with sagebrush. The area west of Dove Creek is dominated
by sagebrush, but the habitat is highly fragmented by agricultural
fields. Lek counts in the Dove Creek area were more than 50 males in
1999, suggesting a population of about 245 birds (C = High male count;
C/0.53 + (C/0.53 x 1.6)), but declined to 2 males in 2009 (CDOW 2009b,
p. 71), suggesting a population of 10 birds at that time. Low sagebrush
canopy cover, as well as low grass height, exacerbated by drought, may
have led to nest failure and subsequent population declines (Connelly
et al. 2000a, p. 974; Apa 2004, p. 30). The 2014 population estimate
was 24 individuals (CPW 2014d, p. 1).
Combined, the Monticello-Dove Creek estimated population size in
2014 was 98 individuals (CPW 2014d, p. 1). Most population estimates
from 1996 to 2014 are well below the population target of 500 breeding
birds (based on a 10-year average) for the Monticello-Dove Creek
population, as set forth by the RCP (CPW 2013a, p. 12; GSRSC 2005, p.
278). Likewise, most population estimates from 1996 to the present time
are well below the population target of 250 birds for each
subpopulation alone (CPW 2013a, p. 12).
Pi[ntilde]on Mesa Population--The Pi[ntilde]on Mesa population
occurs on the northwestern end of the Uncompahgre Plateau in Mesa
County, about 35 km (22 mi) southwest of Grand Junction, Colorado.
Gunnison sage-grouse likely occurred historically in all suitable
sagebrush habitat in the Pi[ntilde]on Mesa area, including the
Dominguez Canyon area of the Uncompahgre Plateau, southeast of
Pi[ntilde]on Mesa proper (Rogers 1964, pp. 22, 114). Their current
distribution is approximately 18,080 ha (44,678 ac) (GSRSC 2005, p. 87)
which, based on a comparison of potential presettlement distribution,
is approximately 6 percent of presettlement habitat on the northern
portion of the Uncompahgre Plateau in Mesa County, Colorado, and Grand
County, Utah. The 2014 estimated population was 182 birds (CPW 2014d,
p. 1), much greater than the 2012 estimate of 54 birds. Over the last 4
years, CPW has translocated 93 sage-grouse to this area, which may have
contributed to the increase observed over the past 2 to 4 years (CPW
2014c, entire), in addition to the discovery of two formerly unknown
leks in 2012 (CPW 2012a, pp. 2-3). Population estimates from 1996 to
2014 are below the population target of 200 breeding birds (based on a
10-year average) for the Pi[ntilde]on Mesa population, as set forth by
the RCP (CPW 2013a, p. 11; GSRSC 2005, p. 285). Of 12 known leks, only
4 were active in 2012 (CPW 2012a, pp. 2-3). The Pi[ntilde]on Mesa area
may have other leks as well, but the high percentage of private land, a
lack of roads, and heavy snow cover during spring make locating new
leks difficult (CDOW 2009b, p. 109).
Crawford Population--The Crawford population of Gunnison sage-
grouse includes approximately 14,170 ha (35,015 ac) of occupied habitat
in Montrose County, Colorado, about 13 km (8 mi) southwest of the town
of Crawford and north of the Gunnison River. Basin big sagebrush (A. t.
ssp. tridentata) and black sagebrush (A.
[[Page 69200]]
nova) dominate the mid-elevation uplands (GSRSC 2005, p. 62). The 2014
estimated population was 157 individuals (CPW 2014a, p. 1), much
greater than the 2010 estimate of 20 birds, and 2011 estimate of 44
birds. This observed increase could be, in part, the product of the
translocation of 72 birds to the Crawford population from 2011 to the
spring of 2013 (CPW 2014c, entire), although natural increases or other
reasons not understood could also be contributing. Furthermore, new lek
count techniques for this population were implemented in 2012 (Gunnison
County 2013a, p. 190), and increased survey efforts may be partly
responsible for observed increases in high male counts and population
estimates (Figure 3). Population estimates from 1996 to 2014 are well
below the population target of 275 breeding birds (based on a 10-year
average) for the Crawford population, as set forth by the RCP (CPW
2013a, p. 11; GSRSC 2005, p. 264). Three leks are currently active in
the Crawford population (CPW 2012a, p. 1), all on BLM lands near an 11-
km (7-mi) stretch of road. This area represents the largest contiguous
sagebrush plant community within the occupied area of the Crawford
population (GSRSC 2005, p. 64).
Cerro Summit-Cimarron-Sims Mesa Population--This population is
divided into two geographically separate subpopulations, both in
Montrose County, Colorado: The Cerro Summit-Cimarron and Sims Mesa
subpopulations. It is unknown whether sage-grouse currently move
between these subpopulations.
The Cerro Summit-Cimarron subpopulation is centered about 24 km (15
mi) east of the City of Montrose. Rogers (1964, p. 115) noted a small
population of sage-grouse in the Cimarron River drainage, but did not
report population numbers. The same publication also reported that four
individual birds were observed during lek counts at Cerro Summit in
1959. Habitat in this subpopulation area includes 15,039 ha (37,161 ac)
of patchy sagebrush habitat fragmented by oakbrush and irrigated
pastures. Four leks are currently known in the Cerro Summit-Cimarron
group, although only two have been active in recent years (GSRSC 2005,
p. 257; CPW 2012a, entire).
The Sims Mesa area, about 11 km (7 mi) south of Montrose, consists
of small patches of sagebrush fragmented by pi[ntilde]on-juniper,
residential and recreational development, and agriculture (CDOW 2009b,
p. 43). Rogers (1964, p. 95) recorded eight males from lek counts at
Sims Mesa in 1960. In 2000, the CPW translocated six Gunnison sage-
grouse from the Gunnison Basin to Sims Mesa (Nehring and Apa 2000, p.
12). There is only one currently known lek in the Sims Mesa and, since
2003, it has not been attended by Gunnison sage-grouse. However, lek
counts on Sims Mesa did not occur in 2011. A lek is designated historic
when it is inactive for at least 10 consecutive years, according to CPW
standards. Therefore, the current status of the Sims Mesa lek is
unknown (CDOW 2009b, p. 7; CPW 2012a, p. 1).
The Cerro Summit-Cimarron-Sims Mesa population estimate in 2014 was
74 individuals (CPW 2014a, p. 1), with all birds in the Cerro Summit-
Cimarron areas. Population estimates from 1996 to 2014 are below the
population target of 100 breeding birds (based on a 10-year average)
for this population, as set forth by the RCP (CPW 2013a, p. 11; GSRSC
2005, p. 258).
Available information indicates that some birds translocated to the
Crawford area between 2011 and 2013 went to the Cerro Summit-Cimarron
area, then moved back to Crawford (Crawford Area Gunnison Sage-grouse
Working Group 2014, p. 3). Translocated birds also returned to the
Gunnison Basin permanently (Crawford Area Gunnison Sage-grouse Working
Group 2014, p. 3). Genetic information (Oyler-McCance et al. 2005, pp.
635-636; SMBGSWG 2009, p. 9) indicates that there was past gene flow
between the Cerro Summit-Cimarron population and the San Miguel
population. Therefore, we consider the Cerro Summit-Cimarron population
to be an important linkage area, providing connectivity between the two
largest populations, the Gunnison Basin and the San Miguel populations,
as well as the Crawford population.
Poncha Pass Population--The Poncha Pass Gunnison sage-grouse
population is located in Saguache County, approximately 16 km (10 mi)
northwest of Villa Grove, Colorado. The known population distribution
includes 11,229 ha (27,747 ac) of sagebrush habitat from the summit of
Poncha Pass extending south for about 13 km (8 mi) on either side of
U.S. Highway 285. Sagebrush in this area is generally intact with
little fragmentation, and habitat quality throughout the area appears
adequate to support a population of the species (Nehring and Apa 2000,
p. 25). Despite this, the area has struggled to sustain a viable
population. San Luis Creek runs through the area, providing a perennial
water source and wet meadow riparian habitat for brood-rearing. Decker
and Rock Creeks also provide water most of the year. However, water
flows in the area have been much lower and less dependable in recent
years due to drought conditions (Nehring 2013a, pers. comm.).
The Poncha Pass population was reintroduced in the 1970s in a
portion of the San Luis Valley where Gunnison sage-grouse were thought
to have been extirpated by the 1950s (Rogers 1964, pp. 22, 27, 116).
Reestablishment of this population began with 30 birds translocated
from the Gunnison Basin in 1971 and 1972 (GSRSC 2005, p. 94). In 1992,
a CPW effort to simplify hunting restrictions inadvertently opened the
Poncha Pass area to sage-grouse hunting, and at least 30 grouse were
harvested from this population. Due to declining population numbers
since the 1992 hunt, CPW translocated 24 additional birds from the
Gunnison Basin in the spring of 2000 (Nehring and Apa 2000, p. 11). In
2001 and 2002, an additional 20 and 7 birds, respectively, were moved
to Poncha Pass by the CPW (GSRSC 2005, p. 94).
Translocated females have bred successfully (Apa 2004, pers.
comm.), and male display activity resumed on the historical lek in the
spring of 2001. The only known lek is located on BLM-administered land
(CDOW 2011a, p. 1; CPW 2012a, p. 3). A high male count of 3 males
occurred in 2012, resulting in an estimated population size of 15 for
the Poncha Pass population. In 2013, no birds were counted at leks or
in surrounding habitat despite considerable survey efforts, suggesting
a population estimate of zero birds. In the fall of 2013, CPW
translocated 17 birds to the Poncha Pass population from the Gunnison
Basin. As of January 2014, 10 of these birds were known to be surviving
(Nehring 2014, pers. comm.). In 2014, CPW translocated 10 more birds to
the area. Sixteen birds were known to survive into summer of 2014 (all
translocated birds had telemetry transmitters). Poncha Pass current and
past population estimates from 1996 to 2013 are well below the
population target of 75 birds, as set forth by the RCP (CPW 2013a, p.
12; GSRSC 2005, p. 291). We note that given the history of this
population, lack of unique genetics (all sage-grouse were introduced
from the Gunnison Basin), and concerns about translocation success, we
do not consider this population necessary to the recovery of the
species.
Additional Special Status Information
The Gunnison sage-grouse has an International Union for
Conservation of Nature (IUCN) Red List Category of ``endangered''
(Birdlife International 2009). NatureServe currently ranks the Gunnison
sage-grouse as G1-Critically
[[Page 69201]]
Imperiled (Nature Serve 2010, entire). The Gunnison sage-grouse is on
the National Audubon Society's Watch List 2007 Red Category, which is
``for species that are declining rapidly or have very small populations
or limited ranges, and face major conservation threats.'' This
information is provided here for background only; these assessments
were not factored into our analysis or listing determination in this
rule.
Summary of Changes From the Proposed Rule
Based upon our review of the public comments, comments from other
Federal and State agencies, peer review comments, issues raised at the
public hearing, and new relevant information that has become available
since the publication of the proposal, we have reevaluated our proposed
listing rule and made changes as appropriate. Other than minor
clarifications and incorporation of additional information on the
species' biology and populations, this determination differs from the
proposal in the following ways:
(1) Based on our analyses of the potential threats to the species,
we have determined that Gunnison sage-grouse does not meet the
definition of an endangered species, contrary to our proposed rule
published on January 11, 2013 (78 FR 2486).
(2) Based on our analyses, we have determined that the species
meets the definition of a threatened species. Subsequently, pursuant to
this final rule, the species will be added to the list of threatened
species set forth in 50 CFR Part 17.
(3) We have expanded the discussion of Ongoing and Future
Conservation Efforts, in Factor A below.
(4) We have found that the threat from current residential
development in the Gunnison Basin is not as high as we previously
concluded. See Factor A analysis and discussion.
Summary of Peer Review and Public Comments
In our January 11, 2013, proposed rules for Gunnison sage-grouse
(proposed listing, 78 FR 2486; proposed critical habitat designation,
78 FR 2540), we requested written public comments on the proposal from
all interested parties. At various times, public comment periods were
extended or reopened (see Previous Federal Actions), with a final
comment period on both proposals ending on December 2, 2013. We
contacted appropriate State and Federal agencies, county governments,
elected officials, scientific organizations, and other interested
parties and invited them to comment. We also published notices inviting
general public comment in local newspapers throughout the species'
range.
Between January 11, 2013, and December 2, 2013, we received a total
of 36,171 comment letters on the listing and critical habitat
proposals. Of those letters, we determined that approximately 445 were
substantive comment letters; 35,535 were substantive form letters; and
191 were non-substantive comment letters. Substantive letters generally
contained comments pertinent to both proposed rules, although the vast
majority of comments were related to the proposed listing rule.
Responses to comments related to critical habitat are provided in the
final rule to designate critical habitat for Gunnison sage-grouse,
published elsewhere in today's Federal Register. Also, we held three
public hearings between November 19 and 21, 2013, in response to
requests from local and State agencies and governments; we received
oral comments during that time (see Previous Federal Actions). All
substantive information provided during all comment periods and
hearings that pertains to the listing of the species has been
incorporated directly into this final rule or addressed below. For the
readers' convenience, we combined similar comments and responses.
Comments From Peer Reviewers
In accordance with our peer review policy published in the Federal
Register on July 1, 1994 (59 FR 34270), we solicited expert opinion
from five independent and qualified individuals with scientific
expertise on Gunnison sage-grouse biology and conservation. The purpose
of the peer review was to ensure that our decisions are based on
scientifically sound data, assumptions, and analyses, based on the
input of appropriate experts and specialists. We received written
responses from all five peer reviewers. We reviewed all comments
received from the peer reviewers for substantive issues and new
information regarding the listing of the Gunnison sage-grouse. One peer
reviewer concluded that our proposals included a thorough and accurate
review of the available scientific and commercial data on Gunnison
sage-grouse, but did not provide substantive comments. The remaining
four letters provided additional relevant information on biology,
threats, and scientific research for the species. Two peer review
letters were opposed to the proposed listing and questioned our
rationale and determinations. All substantive comments from peer
reviewers are incorporated directly into this final rule or addressed
in the summary of comments below.
(1) Comment: One peer reviewer noted that population growth models
of greater sage-grouse (C. urophasianus) indicate adult annual survival
is the most sensitive vital rate. However, in the proposed rule, we
said that limitations in the quality and quantity of nesting and early
brood-rearing habitats, in particular, are especially important because
Gunnison sage-grouse population dynamics are most sensitive during
these life-history stages (GSRSC 2005, p. G-15).
Our Response: Juvenile recruitment has been identified as the most
important demographic factor influencing or limiting greater and
Gunnison sage-grouse population growth rates and viability (Connelly et
al. 2004, p. 3-11, GSRSC 2005, p. 173). In a recent demographic and
population viability study of Gunnison sage-grouse (Davis 2012),
juvenile survival was found to be the most influential vital rate in
the Gunnison Basin population, a relatively stable population. However,
adult survival was more influential in the San Miguel population, a
smaller and steeply declining population where no juvenile recruitment
occurred (Davis 2012, pp. 89, 93). Therefore, both juvenile survival
and adult survival rates appear to be important to the species'
viability. This topic is discussed further under Factor E in this final
rule.
(2) Comment: One peer reviewer stated that the methods and
rationale regarding the proposed rule's evaluation of residential
development and estimated housing development in the Gunnison Basin are
not clear for the following reasons: It was unclear how the potential
spatial configuration of new housing units was estimated; thus
calculations for habitat lost directly or indirectly are not
transparent. The reviewer stated that the conclusion that the species
should be listed as endangered relies heavily on the analysis of
potential threats of additional anthropogenic infrastructure given
increasing human populations. The peer reviewer commented that there
are potential flaws in the estimated impacts of residential impact in
the Gunnison Basin, which relied primarily on Aldridge et al. (2012,
entire). The peer reviewer noted that to establish the scientific
credibility of these conclusions, additional information is required
describing the methodology and data used in the analysis as well as
reporting the results; for example, citing the spatial data sources,
specifically
[[Page 69202]]
establishing the methods used to come to the level of potential impact
(spatially and temporally), providing results specific to each
analysis, and specifically establishing the assumptions made. The peer
reviewer also stated that an analysis of residential development in the
satellite populations is lacking.
Our Response: In Factor A of this final rule, we reevaluate the
threat of residential development in the Gunnison Basin and in the six
satellite populations, and explain the framework for our assessment. In
that revised analysis, based on new information regarding the location
and magnitude of past development patterns in Gunnison sage-grouse
habitat in the Gunnison Basin, we avoid the use of spatial zones of
influence to estimate or extrapolate potential impacts of current and
future development, focusing instead on human population growth rates
and available developable private lands in occupied habitat.
(3) Comment: A peer reviewer noted that the proposed rule analysis
indicated that approximately 85 percent of occupied habitat in the
Gunnison Basin has an increased likelihood of current or future road-
related disturbance. This conclusion would suggest that the vast
majority of sagebrush habitats in the Gunnison Basin are within 700 m
of a road, an exceptionally dense road network--as a comparison, Knick
et al. 2011 (chapter 12 in Studies in Avian Biology No. 38 page 215)
estimated that 89 percent of sage-grouse habitats were within 2.5 km of
a road in Western Association of Fish and Wildlife Agencies Management
Zone 7 (Colorado Plateau), road densities less than those reported
here. The reviewer suggested that we provide more specificity on how we
analyzed roads. The reviewer noted that, given that this analysis is
specific to the spatial scale of the potential spread of invasive weeds
associated with roads in general, it may benefit the discussion to
include the amount of habitat within 700 m of improved surface roads as
well as all roads (assuming two-tracks are included as roads in this
analysis).
Our Response: Our analysis included all road types (primary,
secondary, etc.) in occupied habitat in the Gunnison Basin, hence the
relatively high density of road networks. We did not differentiate by
road type, as our primary intent was to estimate exposure of occupied
habitat to road networks in general. We revised this final rule to
clarify that the extent and severity of weed invasion would vary by
road type. See further discussion under ``Roads'' in Factor A.
(4) Comment: One peer reviewer commented that the proposed rule
discusses the short-lived benefits of fire in sage-grouse habitats,
including a flush of understory vegetation and forbs. The peer reviewer
noted that the proposed rule states that beneficial effects of fire
were found by studies in mesic habitats and that, therefore, some
benefits may be expected from fire in those habitat types (but this is
contradictory to the previous statement). The reviewer stated that
effects in Wyoming sagebrush, where most studies have taken place, may
be different from those in mountain sagebrush types (such as in
Gunnison sage-grouse range).
Our Response: As presented in this final rule, effects of fire in
sagebrush habitat and to sage-grouse are highly variable. A clear
positive response of Gunnison or greater sage-grouse to fire has not
been demonstrated (Braun 1998, p. 9). The few studies that have
suggested fire may be beneficial for greater sage-grouse were primarily
conducted in mesic areas used for brood-rearing (Klebenow 1970, p. 399;
Pyle and Crawford 1996, p. 323; Gates 1983, in Connelly et al. 2000c,
p. 90; Sime 1991, in Connelly et al. 2000a, p. 972). In mesic habitat,
small fires may maintain a suitable habitat mosaic by reducing shrub
encroachment and encouraging understory, herbaceous growth. However,
without available nearby sagebrush cover, the utility of these sites is
questionable, especially within the six small Gunnison sage-grouse
populations where fire could further degrade the remaining habitat.
More recent research related to Gunnison sage-grouse indicated that due
to the fragmented nature of remaining sagebrush habitat across the
species' range, prescribed fire may be inappropriate if the goal is to
improve sagebrush and overall habitat conditions for the species (Baker
2013, p. 8). This topic is discussed further under Factor A in this
final rule.
(5) Comment: A peer reviewer recommended that our analysis include
more discussion on the role of water developments in the proliferation
of West Nile virus. The reviewer cited a study by Walker and Naugle
(2011), arguing that West Nile outbreaks in small, isolated sage-grouse
populations--similar to all except perhaps the Gunnison Basin
population of Gunnison sage-grouse--may result in extirpation. Given
the potential impact to populations from West Nile virus and the
predicted spread of this disease associated with climate change, the
reviewer stated that the effect of anthropogenic water sources that
harbor mosquitoes should be analyzed.
Our Response: In this rule, we reevaluated West Nile virus as a
threat to Gunnison sage-grouse and included several new citations. We
did not conduct a landscape analysis on the precise quantity or
distribution of water developments, but instead focused our analysis on
the known distribution of West Nile virus across Gunnison sage-grouse
range. In this final rule we find that, due to the known and potential
presence and distribution of West Nile virus across the majority of
Gunnison sage-grouse range, the high risk of mortality and population-
level impacts based on the biology of the species, and the immediacy of
those potential impacts, West Nile virus is a potential future threat
to Gunnison sage-grouse throughout its range. The threat of West Nile
virus is currently lower in the high-elevation areas, such as the
Gunnison Basin and most of the Pi[ntilde]on Mesa populations, but we
expect it to increase in the near term due to increased drought and the
predicted effects of climate change. This topic is discussed in detail
under Factor C of this rule.
(6) Comment: A peer reviewer stated that limited evidence is
provided to establish predation as a substantial threat to Gunnison
sage-grouse.
Our Response: We agree that research and data linking predation and
Gunnison sage-grouse abundance and viability are limited. However,
available scientific information (primarily for greater sage-grouse)
presented in this rule indicates that, particularly in areas of
intensive habitat alteration and fragmentation, and in smaller less
resilient populations, sage-grouse productivity and, potentially,
population persistence could be negatively affected by predation.
Because the Gunnison and greater sage-grouse have similar behavior and
life-history traits, it is reasonable to assume that predator impacts
on Gunnison sage-grouse are similar to those observed in greater sage-
grouse. The best available information indicates that predation is
having an impact on Gunnison sage-grouse, particularly in the satellite
populations, where there is some evidence that predation is affecting
chick and juvenile survival, especially in smaller populations. Based
on the greater sage-grouse data and the limited data available for
Gunnison sage-grouse, we conclude that predation is a threat. While
predation likely acts as a threat in localized areas across the range
of the species, the stability of the Gunnison Basin population over the
last 19 years indicates that predation is not having a significant
impact on that population.
[[Page 69203]]
We believe, however, that the effects of predation are more pronounced
in the satellite populations. Given the stability of the Gunnison Basin
population, we do not believe that the magnitude of this threat is
significant at the rangewide level. This topic is discussed in detail
in Factor C of the rule.
(7) Comment: A peer reviewer noted that the proposed rule's
analysis on non-renewable energy development is lacking.
Our Response: This final rule includes a revised and expanded
evaluation of mineral and energy development (Factor A).
(8) Comment: A peer reviewer stated that there are no data to
support the conclusion that habitat conditions with respect to grazing
are better on public lands than private lands, due in part to land
health standards and more regulation.
Our Response: We agree and have revised our statement in the final
rule to more accurately reflect that in our analysis of grazing under
Factor A.
(9) Comment: A peer reviewer noted that the proposed rule states,
with respect to fences, that ``we anticipate that the effect on sage-
grouse populations through the creation of new raptor perches and
predator corridors into sagebrush habitats is similar to that of
powerlines.'' The reviewer did not think this assumption was correct.
The commenter noted that differences in height between a fence post and
a utility pole would theoretically result in different spatial scales
of functional habitat loss due to differences in the distance from the
perch a predator could see while perched.
Our Response: The final rule has been revised to state that fence
posts create perching places for raptors and corvids, which may
increase their ability to prey on sage-grouse (Braun 1998, p. 145;
Oyler-McCance et al. 2001, p. 330; Connelly et al. 2004, p. 13-12).
This topic is discussed in detail in Factor A of this rule.
(10) Comment: A peer reviewer suggested that we review a recent
article by Blomberg et al. 2012, related to climate change and invasive
plants. This article suggests that characteristics of climate and
landscape disturbance influence the dynamics of greater sage-grouse
populations.
Our Response: We reviewed this article and cited it in Factor A
(Invasive Plants) and Factor E (Drought and Extreme Weather) of this
rule.
(11) Comment: A peer reviewer noted that the Utah population of
Gunnison sage-grouse was at its highest in the 1970s and 1980s (San
Juan County Working Group (SJCWG) 2000, Lupis 2005, Prather 2010).
During this period, the peer reviewer stated, the primary agricultural
crops in the county were winter wheat (Triticum spp.) and dryland
alfalfa (Medicago spp.). Many growers did not use herbicides or
insecticides at this time because of the slim profit margin in growing
these crops. The peer reviewer suggested that these practices may have
resulted in a greater arthropod abundance as a result of increased
green vegetation and forb availability, providing more food resources
for Gunnison sage-grouse. The reviewer also reported that during this
period landowners frequently reported observing flocks of sage-grouse
in their fields during harvest and post-harvest periods.
Our Response: While sage-grouse may forage on agricultural
croplands (Commons 1997, pp. 28-35), when possible, they tend to avoid
landscapes dominated by agriculture (Aldridge et al. 2008, p. 991).
Influences resulting from agricultural activities extend into adjoining
sagebrush, and include increased predation and reduced nest success due
to predators associated with agriculture (Connelly et al. 2004, p. 7-
23). Agricultural lands provide some benefits for sage-grouse as some
crops such as alfalfa (Medicago sativa), winter wheat (Triticum
aestivum), and pinto bean sprouts (Phaseolus spp.) are eaten or used
seasonally for cover by Gunnison sage-grouse (Braun 1998, pers. comm.,
Lupis et al. 2006, entire). Agricultural fields and their management
may provide a surplus of arthropods and forbs for Gunnison sage-grouse,
and for hens with broods, in particular. Despite these seasonal
benefits, crop monocultures do not provide adequate year-round food or
sagebrush cover (GSRSC 2005, pp. 22-30). This topic is discussed in
Factor A of this rule (Conversion to Agriculture).
(12) Comment: One peer reviewer felt that the proposed rule
neglected to discuss the importance of Conservation Reserve Program
(CRP) lands in Utah to Gunnison sage-grouse.
Our Response: Lands within the occupied range of Gunnison sage-
grouse enrolled into the CRP occur within Dolores and San Miguel
counties in Colorado, and San Juan County in Utah (USDA FSA 2010,
entire). A significant portion of the agricultural lands in the
Monticello subpopulation are enrolled in the CRP program, and some CRP
lands are sometimes used by Gunnison sage-grouse as early-brood-rearing
and summer-late fall habitat when they are part of a landscape that
otherwise encompasses the species' seasonal habitats (Lupis et al.
2006, pp. 959-960; Ward 2007, p. 15). We therefore acknowledge the
benefits of CRP lands to Gunnison sage-grouse, as habitat provided
under this program is generally more beneficial to the species than
lands under more intensive agricultural uses such as crop production.
However, CRP lands are generally lacking in the sagebrush and shrub
components typically critical to the survival and reproduction of
Gunnison sage-grouse and vary greatly in plant diversity and forb
abundance (Lupis et al. 2006, pp. 959-960; Prather 2010, p. 32). As
such, these CRP lands are generally of lower value or quality than
native sagebrush habitats. This topic is discussed further in Factor A
(Conversion to Agriculture).
(13) Comment: A peer reviewer noted that adult survival and nesting
success in San Juan County was higher (Lupis 2005, Ward 2007) than that
reported for other populations (Young 1994, Commons 1997, Apa 2004).
The reviewer hypothesized that this difference may be due to the effort
in San Juan County to reduce mammalian and corvid depredation (Lupis
2005, Ward 2007).
Our Response: While we acknowledge that predator control may be
effective under certain circumstances, the cited studies did not
evaluate the effect of predator control, nor was that their objective.
They only speculated regarding the potential positive effects of
predator control on the Monticello (San Juan County) population of
Gunnison sage-grouse. This topic is discussed further in Factor C
(Predation) of this rule.
(14) Comment: A peer reviewer reported that the Gunnison sage-
grouse population in San Juan County may be stable or increasing based
on increases in brood sizes and hatch success between 1974 and 2005
(UDWR 1974; Lupis 2005). This reviewer noted that this hypothesis was
not supported by lek count indices, which indicated that the population
was declining.
Our Response: Lek count data from 1996 through 2014 indicate a
decline in the Monticello-Dove Creek population (located in the
adjacent counties of San Juan, UT, and Dolores, CO, respectively)
collectively and in both of these populations individually. Further,
current population estimates are well below the Rangewide Conservation
Plan (RCP) population target of 250 birds for each population alone
(CPW 2013, p. 12). Sample size for the aforementioned study was limited
to three nests, and predator control at the time may have contributed
to relatively high nesting success (Lupis 2005, entire); the inference
to be drawn from the study is, therefore, limited. The best available
[[Page 69204]]
scientific information indicates that the Monticello-Dove Creek
population is neither stable nor secure. This topic is discussed
further in this rule in the Current Distribution and Population
Estimates and Trends section below; and in Factor E (Small Population
Size and Structure).
(15) Comment: A peer reviewer provided data and information from
pertinent studies conducted in Utah and Colorado that the reviewer
thought could improve our analysis.
Our Response: We reviewed the provided study information and
literature and found that most had already been considered in our
proposed rule. In this final rule, we included all new studies, data,
and information relevant to our evaluation.
(16) Comment: A peer reviewer thought that the proposed rule was
missing a description and summary of the two decades of conservation
actions completed by local communities, landowners, public and private
agencies, and organizations in Utah and Colorado to conserve the
species. The reviewer indicated that stakeholders in both States
dedicated significant resources to conservation of the species that
have abated numerous threats. The peer reviewer recommended expanding
discussion of the efforts of the local working groups, the State
agencies, nongovernmental organizations, and counties, as well as
Natural Resources Conservation Service (NRCS) programs, including the
Sage-grouse Initiative Program.
Our Response: We recognize the contributions made by multiple
partners including private citizens, nongovernmental organizations, and
Tribal, State, and Federal agencies that are actively engaged in
conservation efforts across the range of Gunnison sage-grouse. Numerous
conservation actions have been implemented for Gunnison sage-grouse,
and these efforts have provided and will continue to provide
conservation benefit to the species. The CCAA, Gunnison Basin CCA,
conservation plans, habitat improvement projects, and similar
conservation efforts that address habitat-related issues are described
and evaluated under Factor A (see Conservation Programs and Efforts
Related to Habitat Conservation) in this rule. Laws and regulations,
conservation easements, and other regulatory mechanisms are evaluated
under Factor D. Scientific research activities are described under
Factor B and throughout this rule where applicable. Also, throughout
this rule, conservation efforts are described under the relevant factor
section.
(17) Comment: A peer reviewer stated that the proposed rule
provides information regarding the estimated historical occupied
Gunnison sage-grouse habitats, based largely on estimates of potential
habitats. As such, these figures may overestimate the historical range
of the species. The commenter noted that it is logical to assume that,
if a species' habitat declines, so will the population. However, the
peer reviewer could not find any data to support the idea that
populations have declined over time.
Our Response: Our listing decision is based on the current status
of Gunnison sage-grouse and the current and future threats to the
species and its habitat. However, the loss of historical range and
decline in abundance, and the associated causes, are informative in
that they can be used to help forecast how populations and the species
may respond to current and future threats.
The onset of Euro-American settlement in the 1800s resulted in
significant alterations to sagebrush ecosystems throughout North
America, primarily as a result of urbanization, agricultural
conversion, and irrigation projects (West and Young 2000, pp. 263-265;
Miller et al. 2011, p. 147). Areas in Colorado that supported basin big
sagebrush were among the first sagebrush community types converted to
agriculture because their typical soils and topography are well suited
for agriculture (Rogers 1964, p. 13). Decreases in the abundance of
sage-grouse paralleled the loss of range (Braun 1998, pp. 2-3), and a
gradual but obvious decrease in sage-grouse distribution and numbers in
Colorado had begun around 1910 (Rogers 1964, pp. 20-22).
The best available information indicates a reduction of Gunnison
sage-grouse distribution since Euro-American settlement in the 1800s,
with evidence of the loss of peripheral populations (Schroeder et al.
2004, p. 371, and references therein) and a northward and eastward
trend of extirpation (Schroeder et al. 2004, p. 369, and references
therein), meaning western and southern extents of the species' former
range are now lost. Based on historical records, museum specimens, and
potential sagebrush habitat distribution, the potential historical
range of Gunnison sage-grouse was estimated to have been 21,376 square
miles, or 13,680,590 ac (GSRSC 2005, pp. 32-35, as adapted from
Schroeder et al. 2004, entire). This range included parts of central
and southwestern Colorado, southeastern Utah, northwestern New Mexico,
and northeastern Arizona (Schroeder et al. 2004, pp. 368, 370).
Braun et al. (2014, entire) provides more detail on historical
distribution in Colorado that largely matches Schroeder et al. (2004).
Not all of this historical range would have been occupied at any one
time. The species' estimated current range is 1,822 square miles, or
1,166,075 ac, in central and southwestern Colorado, and southeastern
Utah (Figure 1) (GSRSC 2005, pp. 32-35, as adapted from Schroeder et
al. 2004, entire). Based on these figures, the species' current range
represents about 8.5 percent of its historical range (GSRSC 2005, p.
32). Similarly, Schroeder et al. (2004, p. 371) estimated the species'
current overall range to be 10 percent of potential presettlement
habitat (prior to European settlement in the 1800s). As estimated in
our final rule to designate critical habitat for Gunnison sage-grouse
(published elsewhere in today's Federal Register), the species'
``overall range'' includes an estimated 1,621,008 ac in southwestern
Colorado and southeastern Utah, comprising 923,314 ac (57 percent) of
occupied habitat and 697,694 ac (43 percent) of unoccupied habitat.
Based on these figures, the current overall range of 1,621,008 acres
represents approximately 12 percent of the potential historical range
of 13,680,640 ac. The estimates above indicate that approximately 88 to
93 percent of the historical range of Gunnison sage-grouse has been
lost. This topic is discussed further under our introduction to Factor
A.
(18) Comment: A peer reviewer noted that Davis (2012) suggested
Gunnison sage-grouse populations in the Gunnison Basin declined
slightly over the last 16 years, but that Davis concluded the Gunnison
Basin population, which may comprise 85-90 percent of the entire
population, is relatively stable. Population projection models based on
Davis' 6-year study suggested that the Gunnison sage-grouse population
in the Gunnison Basin is declining. However, the peer reviewer noted
that lek count data extended farther back in time than the demographic
estimates and showed that this population exhibited a considerable
increase, so the peer reviewer indicated that inference from this study
is limited.
Our Response: Based on an integrated analysis of 16 years of lek
count and demographic data (1996-2011), Davis found that the Gunnison
Basin population may have been declining slightly through the period of
study (Davis 2012, p. 137). That study indicated that the Gunnison
Basin population may not be as stable as previously thought, although
the time span of the study may not have been long enough to reveal a
broader pattern
[[Page 69205]]
in a larger cyclical time series (Davis 2012, p. 38). A more recent
manuscript by Davis et al. (in press) states that the Gunnison Basin
population (1996-2012) is ``slightly declining'' (line 24), and, while
the growth rate of this population has been variable, it is ``near
stable'' (line 341). Consider also that the Gunnison Basin population
may not be as large as lek count-based estimates suggest, which are
based solely on counting males (Davis 2012, p. 136). Davis (2012, pp.
134, 136) found that, in comparison to demographic data, lek count data
showed population growth rates that varied wildly and should be
interpreted with caution. This is particularly true for the lek data
collected prior to 1996, before the lek survey methodology was
standardized (Davis 2012, pp. 136-139). Demographic stochastic
simulations resulted in a mean extinction time of 58 years for the
Gunnison Basin population, without removing any birds for translocation
efforts (removal of birds decreased the estimated mean extinction time)
(Davis 2012, pp. 111, 137). Davis (2012, p. 92) noted, however, that if
the study had been conducted just a few years earlier or later, a
different trend across time could have resulted, because it was based
on a 6-year period of time when the population was experiencing a
slight decline. This study and other population viability analyses are
evaluated in detail in Factor E (Small Population Size and Structure)
of this rule.
(19) Comment: One peer reviewer thought that it is difficult to
assess what future conditions hold, be it vegetation responses to
climate change or the effects of population growth and development
resulting in fragmentation and associated effects on the species of
conservation concern. The reviewer thought it is also difficult to
evaluate how a species such as Gunnison sage-grouse might respond to
projected changes, even 5 or 10 years into the future, let alone 50-100
years. Despite these uncertainties, the peer reviewer considered the
short- and long-term viability for six of the seven populations of
Gunnison sage-grouse to be tenuous, at best.
Our Response: We agree with the reviewer that it is difficult to
predict what will happen in the future. However, the Act requires us to
determine if a species is endangered (in danger of extinction
throughout all or a significant portion of its range) or threatened
(likely to become and endangered species within the foreseeable future
throughout all or a significant portion of its range). Thus, we are
required to make assumptions or predictions into the future based on
the best available information.
We agree with the reviewer that the viability of the six smaller
(``satellite'') populations is at risk (see Small Population Size and
Structure below under Factor E).
(20) Comment: A peer reviewer noted that, while the Gunnison basin
population appears to have stabilized more recently within a population
cycle, the number of current and future threats makes one question
whether this population will remain viable into the future. The
reviewer thought existing threats, or levels of threats, appear to
already threaten the Gunnison basin population. This reviewer
questioned whether the remaining Gunnison basin population will
persist, if other smaller populations disappear, which seems likely in
the near future without considerable management efforts, given
projected future threats. The reviewer also questioned whether the
localized nature of a single remaining population in the Gunnison Basin
is enough to prevent extirpation of the species, considering potential
stochastic events and the likely continued and increasing effects of
habitat degradation and fragmentation.
Our Response: Based on the best available information, we found
that survival of the Gunnison Basin population alone would be
insufficient to ensure the species' long-term persistence in the face
of ongoing and future threats (see Factor E (Small Population Size and
Structure)).
(21) Comment: One peer reviewer questioned whether the Service had
access to the considerable amount of telemetry data collected by
Colorado Parks and Wildlife (CPW) in recent years, primarily for birds
located in the Gunnison Basin. This reviewer fully supported the use of
existing information and models, in lieu of restricted access to other
important data. The reviewer thought that the Service had done a
realistic job of proceeding with existing information, whether it be
from model applications to assist with broader habitat identification
across the Gunnison Basin (see Aldridge et al. 2012), or biological
information and responses (i.e., effects of fences on sage-grouse
mortality) based on studies conducted on the closely related greater
sage-grouse.
Our Response: We do not have access to the telemetry data collected
by CPW. This data has not been published. We do have some telemetry
information provided in overview maps and the information was discussed
in meetings.
As pointed out in the Species Information section, Gunnison sage-
grouse and greater sage-grouse (a similar, closely related species)
have similar life histories and habitat requirements (Young 1994, p.
44). In this final rule, we use scientific information specific to the
Gunnison sage-grouse where available but also apply scientific
management principles and scientific information for greater sage-
grouse that are relevant to Gunnison sage-grouse conservation needs and
strategies, a practice followed by the wildlife and land management
agencies that have responsibility for management of both species and
their habitat. We have considered the best available information in our
assessment, including data and studies provided by CPW.
(22) Comment: A peer reviewer stated that the effects of powerlines
are not all the same, depending on the type of the powerline. The peer
reviewer requested that we clarify what types of powerlines we are
referring to, and which were evaluated in each of the studies we
address.
Our Response: As described in this rule, depending on the
infrastructure design, size, location, and site-specific factors,
powerlines can directly affect greater sage-grouse by posing a
collision and electrocution hazard (Braun 1998, pp. 145-146; Connelly
et al. 2000a, p. 974) and can have indirect effects by decreasing lek
recruitment (Braun et al. 2002, p. 10, Walker et al. 2007a, p. 2,644),
increasing predation (Connelly et al. 2004, p. 12-13, Howe et al.
2014), fragmenting habitat (Braun 1998, p. 146), and facilitating the
invasion of exotic annual plants (Knick et al. 2003, p. 612; Connelly
et al. 2004, p. 7-25). We also specify types of powerlines
(transmission or distribution) and their effects on Gunnison sage-
grouse as appropriate. This topic is discussed further in Factor A
(Powerlines) of this rule.
(23) Comment: A peer reviewer commented that the proposed rule
reads as though Wisdom et al. (2011) tested electromagnetic fields and
found sage-grouse avoidance of them. The reviewer indicates that was
not the case. Wisdom et al. (2011) found a correlation between sage-
grouse extirpations and the presence of powerlines. The reviewer
suggested this effect may be related to electromagnetic fields. The
reviewer cautioned that we ensure here, and throughout, that this
supposition is not presented as a finding.
Our Response: We revised our analysis to explicitly state that no
studies have been conducted specifically on the effects of
electromagnetic fields on sage-grouse.
[[Page 69206]]
This topic is discussed further in Factor A (Powerlines) of this rule.
(24) Comment: A peer reviewer noted that Gregg et al. (2004) did
not actually test grazing impacts on vegetation causing reduction in
nest success. Rather, they found that lower heights of grass cover
(below 18 cm) resulted in increased nest predation. The peer reviewer
suggested that careful choice of wording may be necessary to accurately
reflect what was evaluated and found by a study, versus what was
inferred and speculated from the results of the study. The reviewer
stated that our proposed rule suggested that Gregg et al. (2004)
evaluated livestock reduction in grass heights and showed a direct link
to reduced nesting success for sage-grouse, which was not the case.
Our Response: In this final rule, we clarified that, Gregg et al.
(1994, p. 165) speculated that the reduction of grass heights due to
livestock grazing in sage-grouse nesting and brood-rearing areas may
negatively affect nesting success when cover is reduced below the 18 cm
(7 in.) needed for predator avoidance. This topic is discussed further
under Factor A (Domestic Grazing and Wild Ungulate Herbivory).
(25) Comment: A peer reviewer commented that one could argue that
livestock grazing on private lands might be better managed than public
lands, because individual landowners may be more cognizant of grazing
practices on those lands.
Our Response: In this final rule, we state that livestock grazing
allotments containing both Federal and private lands can often be
managed by Federal agencies to meet land health standards through
coordination and cooperation with grazing permittees (BLM 2013c, p. 1-
2). However, we have no information on the extent of grazing,
management, or habitat conditions on private lands in Gunnison sage-
grouse range, and therefore cannot make a definitive assessment of
these areas. Furthermore, although Federal land and livestock grazing
may be more regulated, we cannot make any generalizations about how
habitat conditions in those areas might compare with private lands
where livestock grazing occurs. This topic is discussed further under
Factor A (Domestic Grazing and Wild Ungulate Herbivory).
(26) Comment: A peer reviewer commented that the table displaying
Land Health Standard data on Federal lands in Gunnison sage-grouse
range is confusing.
Our Response: In this final rule, we restructured the table and
included additional columns and figures to better show how numbers were
calculated (see Table 8 in Factor A (Domestic Grazing and Wild Ungulate
Herbivory)). The information in the table was also updated based on
comments received from Federal agencies during the public comment
periods for the proposed rules.
(27) Comment: One peer reviewer commented that mortality of handled
Gunnison sage-grouse (ranging between zero and seven percent) could be
significant. The peer reviewer would prefer to see a summary of the
percentages by study and age class of birds handled and a sample size
to indicate the potential overall population effect. The reviewer
suggested that we link the summary to match with the cited number of
research related mortalities being typically below three percent. The
rule stated that ``Mortality from scientific research is low (two
percent) and is not a threat.'' These all need appropriate citations,
and the differences between these numbers should be reconciled.
Our Response: In this final rule, we describe why, overall, we
expect that scientific research and related conservation efforts, such
as translocation of Gunnison sage-grouse, have a net conservation
benefit for the species. However, some unintended, but minor negative
effects are known to occur in the process. This topic is addressed
further in Factor B (Scientific Research and Related Conservation
Efforts, see especially Table 11 summarizing various research efforts).
(28) Comment: A peer reviewer noted that in our table of
conservation easements, we have cumulated the percentages based on the
area in easements out of the total area (rangewide) considered, as
opposed to taking the average of the percentages for each population.
Our Response: In this final rule we updated conservation easement
information and acres, based on Lohr and Gray (2013, entire) (see
Factor A (Other Regulatory Mechanisms: Conservation Easements)).
Therein, we provide conservation easement acres by population and
rangewide in occupied and unoccupied habitats. We feel this is a better
representation of lands protected under conservation easement for
Gunnison sage-grouse; averaging those values across populations would
not accurately depict protected acres for the species.
(29) Comment: A peer reviewer expressed concern about what the
reviewer perceived as the frequent use of speculation and commentaries
as empirical evidence. The peer reviewer stated that we speculate about
proposed threats (e.g., climate change) that we have no information on
how they may, or may not, affect Gunnison sage-grouse. The reviewer
stated that we also frequently use vague language (i.e., ``may have'',
or ``is likely to'') and then make definitive statements about Gunnison
sage-grouse in support for the proposed listing decision.
Our Response: As noted above, throughout this rule, we have
carefully identified and qualified instances of speculation or
hypotheses from past scientific studies and publications. Our
identification of current and future threats to Gunnison sage-grouse is
based on the best available scientific information, and we acknowledge
where there is uncertainty associated with data or predictions. For
instance, in this final rule, we discuss that climate change
predictions are based on models with assumptions, and there are
uncertainties regarding the magnitude of associated climate change
parameters such as the amount and timing of precipitation and seasonal
temperature changes.
There is also uncertainty as to the magnitude of effects of
predicted climate parameters on sagebrush plant community dynamics.
These factors make it difficult to predict whether, or to what extent,
climate change will affect Gunnison sage-grouse. We recognize that
climate change has the potential to alter Gunnison sage-grouse habitat
by facilitating an increase in the distribution of cheatgrass and
concurrently increasing the potential for wildfires, and reducing
herbaceous vegetation and insect production in drought years, all of
which would have negative effects on Gunnison sage-grouse.
This topic is discussed further in Factor A (Climate Change) of
this rule, and in Factor E (Drought and Extreme Weather).
(30) Comment: A peer reviewer stated that we frequently make
generalizations about the decline of Gunnison sage-grouse abundance,
such as, ``Fragmentation of sagebrush habitats are a primary cause of
the decline of Gunnison and greater sage-grouse populations.'' However,
the reviewer notes, lek counts in the Gunnison Basin population are
currently at historic high levels and have increased substantially
since the mid-1990s. The reviewer further notes that lek counts from
2005-2007 were the highest counts recorded in the Gunnison Basin
population. Since 2007, lek counts in Gunnison Basin have averaged 703
males.
Our Response: Loss, degradation, and fragmentation of Gunnison
sage-grouse habitat is discussed in Factor A of this rule. Population
trends based on 1996-2014 lek count data show stable to
[[Page 69207]]
slightly declining levels from 1996 through 2004, then the high levels
mentioned from 2005-2007; followed by lower but stable levels since
(see Figure 2). The 2008-2014 population level is higher than levels
prior to 2005, but around 20 percent lower than the 2006 peak (CPW
2014e. p.2). Population trends are discussed further in the section,
Current Distribution and Population Estimates and Trends; and Factor E
(Small Population Size and Structure) of this rule. Also see our
response to State Comment 5 below.
(31) Comment: One peer reviewer stated that we had not presented a
case that Gunnison sage-grouse are in danger of extirpation in the
Gunnison Basin. It is the largest of all Gunnison sage-grouse
populations, and three different population viability analyses have all
concluded it is relatively stable.
Our Response: In our proposed rule to list Gunnison sage-grouse as
endangered (78 FR 2486; January 11, 2013), we found that the species is
in danger of extinction throughout its range, primarily due to habitat
loss, degradation, and fragmentation associated with residential and
human development across its range and, in particular, in the Gunnison
Basin. In this final rule we determined that the species is not
currently in danger of extinction throughout its range, but is likely
to become so in the foreseeable future. As a result, this final rule
lists the species as threatened rather than endangered. The basis for
this decision is set out in the Determination section below. We also
assess the three population viability analyses (PVA) for the Gunnison
Basin and other populations in Factor E (Effective Population Size and
Population Viability Analyses).
(32) Comment: A peer reviewer noted that we present the PVA from
the Rangewide Conservation Plan. However, the reviewer noted that there
are two other PVAs we need to address: Garton (2005) and Davis (2012).
Our Response: All three available PVAs for Gunnison sage-grouse are
included in our assessment in this final rule (Factor E, Effective
Population Size and Population Viability Analyses). Also see our
response to peer review comment 31 above.
(33) Comment: A peer reviewer noted that in referring to the PVA in
the Rangewide Conservation Plan, we state that small populations (<50
birds) are ``at a serious risk of extinction within the next 50 years
(assuming some degree of consistency of environmental influences in
sage-grouse demography).'' (p. 2531). However, environmental and
democratic stochasticity were incorporated into the model (i.e., the
model does not assume ``consistency of environmental influences'').
Our Response: The RCP and actual PVA (see GSRSC 2005, pp. 170 and
G-27) state that the estimates assumed some degree of consistency of
environmental factors over time. This topic is discussed further in
Factor E (Small Population Size and Structure).
(34) Comment: A peer reviewer commented that we misapply the terms
habitat loss, fragmentation, and loss.
Our Response: In the scientific literature and community there are
widely varying interpretations of habitat loss, degradation, and
fragmentation processes, and various methods are applied to measure
these processes. Therefore, in this final rule, we collectively refer
to these processes as habitat decline, as prefaced in the Factor A
section below. However, we do not alter the terminology as applied by
peer-reviewed or other studies. For instance, if a particular study
evaluated and presented results on habitat fragmentation, we did not
interpret the study or authors to mean habitat loss, instead. This
topic is discussed further in our introduction to Factor A in this
rule.
(35) Comment: A peer reviewer stated that we argue more than once
that while individual human activities or features may not be a
significant threat, it is the cumulative impact of all these features
that threatens the Gunnison sage-grouse. However, the peer reviewer
stated that this reasoning ignores the spatial (and temporal) variation
in these potential threats. The reviewer is of the opinion that
proposed threats are not uniformly distributed across space and
therefore will not uniformly impact Gunnison sage-grouse populations.
The reviewer stated that development will only impact a very small
proportion of the habitat in Gunnison Basin and will be restricted to
zoned areas. The reviewer stated that preliminary analyses indicate
that Gunnison sage-grouse are flexible in their movement patterns and
the habitats they use (CPW Demography and Movement project, in prep.).
The reviewer stated that the cumulative negative impacts are not as
likely as we seem to assume.
Our Response: The historic loss of habitat and current isolation of
once connected populations, the declining status of several satellite
populations, and presence of current and future threats to habitat all
indicate that the cumulative loss or decline of habitat has negatively
influenced populations and the species as a whole and is likely to
continue to do so into the future. This topic is discussed further in
our introduction to Factor A in this rule. Threats to Gunnison sage-
grouse habitat are also discussed under Factor A in this rule. We agree
that future residential development in occupied habitat in the Gunnison
Basin is likely to be more limited than we presented in the proposed
rule (see Factor A (Residential Development), but nonetheless find, for
the reasons stated in Factor A, that this development remains a threat
to the species and supports our determination that the species is
likely to become in danger of extinction throughout its range in the
foreseeable future.
(36) Comment: A peer reviewer noted that, related to livestock
grazing, Williams and Hild (2011) showed that vegetation conditions in
the Gunnison Basin met, or exceeded, the habitat structural guidelines
in the Rangewide Conservation Plan. The peer reviewer also stated that
we misrepresented the objective of this study in our proposed rule,
stating that it was not a grazing study and therefore our criticism is
not valid. With 392 transects distributed across Gunnison Basin for
this study, the reviewer did not understand our statement that
``sampling is limited'' (p. 2503).
Our Response: Because livestock grazing effects were not an
objective of the Williams and Hild (2011) study, the extent of past or
ongoing livestock grazing in these areas was not described, nor did the
study compare un-grazed to grazed areas. The Williams and Hild study
found that habitat conditions are likely favorable to Gunnison sage-
grouse in a portion of the Gunnison Basin (Williams and Hild 2011,
entire), although the relationship to livestock grazing effects in
those areas is unknown. In this final rule, we clarify that there is
limited ability to make inferences from this study for other areas in
the Gunnison Basin, due to limitations of the study. Transect locations
for the study were prioritized and selected in areas used by radio-
collared Gunnison sage-grouse, potentially biasing study results.
Therefore, the relationship between livestock grazing and habitat
conditions is unclear in this study, and there is limited ability to
infer from its conditions in other portions of the Gunnison Basin not
prioritized for sampling. This topic is discussed further in Factor A
(Domestic Grazing and Wildlife Herbivory) of this rule.
(37) Comment: A peer reviewer stated that our discussion of
``presettlement'' distribution of Gunnison sage-grouse was highly
speculative. The peer reviewer also stated that we assume that
[[Page 69208]]
Gunnison sage-grouse distribution closely matches the distribution of
sagebrush, and that this assumption is used by some authors (e.g.,
Schroeder, et al. 2004, Wisdom et al. 2011), but is not necessarily
true. The peer reviewer stated that the map by Schroeder et al. (2004)
is not meant to be a definitive description that accurately defines
historical distribution, but a generalization based on available
information (i.e., the model includes areas that are not habitat and
omits other areas that are habitat). The peer reviewer noted that we
also state Gunnison sage-grouse distribution depends on large areas of
contiguous sagebrush. The peer reviewer also noted that this assumption
does not seem to be well supported since Gunnison sage-grouse have
existed in small, isolated populations for decades (Rogers 1964).
Our Response: Related to potential historical range of Gunnison
sage-grouse, and the estimated loss of historical range, see our
response to Peer Reviewer Comment 17 above. Related to our position
that the species depends on sagebrush on a landscape scale for its
survival, the best available science supports this, and it is an
empirical principle widely accepted by sage-grouse biologists and the
scientific community. As discussed in this rule, Gunnison sage-grouse
depend on sagebrush for their survival and persistence, and the
historical and current distribution of the Gunnison sage-grouse closely
matches that of sagebrush (Patterson 1952, p. 9; Braun 1987, p. 1;
Schroeder et al. 2004, p. 364, and references therein). Habitat
fragmentation resulting from human development patterns is especially
detrimental to Gunnison sage-grouse because of their dependence on
large expanses of sagebrush (Patterson 1952, p. 48; Connelly et al.
2004, p. 4-1; Connelly et al. 2011a, p. 72) and more contiguous
sagebrush habitats (Rogers 1964, p. 19; Wisdom et al. 2011, pp. 452-
453). The overall declining status of several of the satellite
populations (despite translocation/augmentation efforts) does not
support the idea that the species is capable of persisting at low
levels or in isolated conditions. Refer to Factor E in this rule for
more discussion on this topic.
(38) Comment: A peer reviewer noted that we describe the genetic
work by Oyler-McCance et al. (1999, 2005) that illustrates the lower
genetic diversity of Gunnison sage-grouse compared to greater sage-
grouse, and the lower genetic diversity of the small Gunnison sage-
grouse populations compared to the Gunnison Basin population. The peer
reviewer asserted that lower genetic diversity may have important
consequences, but it is unlikely to have an effect anytime in the near
future and that it must be demonstrated that low genetic diversity has
negative consequences on individuals and populations.
The peer reviewer stated that it is inappropriate to suggest that
there is a specific population size that is necessary for long-term
population survival from a genetic perspective (i.e., that there should
be 500-5,000 Gunnison sage-grouse in a population for it to be viable).
The peer reviewer commented that the genetic viability of a population
depends on the effective population size, the type of genetic variation
in the population, and type of selection acting on the population. The
peer reviewer noted it is possible that animals can rapidly adapt to
inbreeding by the selective elimination of the genes responsible for
inbreeding depression and although highly speculative, this may be
operating in the small, isolated Gunnison sage-grouse populations. So,
the peer reviewer suggested that to argue that inbreeding depression
due to low genetic diversity is a basis for listing the species as
endangered is not warranted without empirical data focused on this
specific question.
Our Response: In this final rule, we have determined that listing
the species as threatened, not endangered, is the appropriate
determination. We describe the potential negative consequences of
genetic deterioration associated with small population size and
geographic isolation under Factor E (Genetic Risks)). We also discuss
this topic and other relevant information further under Factor E (Small
Population Size and Structure) in this rule.
Comments From States
(1) Comment: The Arizona Game and Fish Department noted that there
are no records of Gunnison sage-grouse ever existing in Arizona, and
estimates of historical range in northeastern Arizona are based on pre-
settlement occurrence of sagebrush (Artemisia spp.), which has largely
been extirpated. Consequently, no viable habitat remains for the
Gunnison sage-grouse in Arizona. Any future restoration efforts should
focus on the remaining core distributions in Colorado and Utah.
Our Response: Identification of potential pre-settlement Gunnison
sage-grouse habitat in Arizona was based on both historical sagebrush
distribution and a 1937 observation of sage-grouse in the northeastern
corner of that state (Schroeder et al. 2004, pp. 368-369, and
references therein). Restoration or reintroduction of Gunnison sage-
grouse in Arizona is not being proposed.
(2) Comment: The Colorado Office of the Governor noted that letters
had been sent from Colorado Parks and Wildlife (CPW) and Colorado
Department of Agriculture (CDA), and recommended that the Gunnison
sage-grouse should be determined not warranted for listing.
Our Response: The Colorado Office of the Governor referenced CPW
and CDA letters in support of a not warranted determination for
Gunnison sage-grouse, but provided no other information or data to
support their position. We acknowledge receipt of letters from CPW and
CDA. Their comments will be addressed in further detail in this
section. Our listing determination for the Gunnison sage-grouse is
explained in this final rule.
(3) Comment: CPW recommended the following hierarchy in the
evaluation of biology and threats.
a. Use of only Gunnison sage-grouse data when it exists.
b. If Gunnison sage-grouse data does not exist, use greater sage-
grouse data closest to Gunnison sage-grouse range in Colorado or Utah.
c. If greater sage-grouse data from adjacent populations does not
exist, then proceed with the appropriate cautions and limited inference
to available information within the range of greater sage-grouse.
Another State commenter suggested that references to greater sage-
grouse be omitted altogether.
Our Response: We generally used the above approach recommended by
CPW, although we did not distinguish between greater sage-grouse data
from populations closest to Gunnison sage-grouse's range. We did not
explicitly state that in the proposed rule--we stated that the ``best
available scientific and commercial data'' were used. We also noted
that we used information specific to the Gunnison sage-grouse where
available but still applied scientific management principles for
greater sage-grouse that we determined were relevant to Gunnison sage-
grouse management needs and strategies. We followed the same approach
in this final rule.
(4) Comment: CPW and CDA stated that lek counts in the San Miguel,
Crawford, and Cerro Summit-Cimarron-Sims Mesa populations have
increased in recent years, in contrast to the statement in the listing
proposal that population trends over the last 12 years indicate that
six of the populations are in decline.
Our Response: We used the same CPW lek survey data that these
comments refer to in our assessment of
[[Page 69209]]
population trends from 2001 through 2012. Our conclusion was that the
six smaller populations had stable to declining numbers from the first
half of the survey period (2001-2006) to the second half of the survey
period (2007-2012). We agree that the three previously mentioned
populations have increased in the past 2-3 years, along with
Pi[ntilde]on Mesa, as indicated in Figure 3 in the proposed listing
rule (78 FR 2492, January 11, 2013). However, these populations are not
at higher levels than in 2001-2006. It should also be noted that these
declining trends in the smaller populations have occurred despite
translocation efforts (see Scientific Research and Related Conservation
Efforts). Without these translocations, bird numbers likely would be
lower for these populations. Furthermore, in this final listing rule,
we analyzed population estimates over a longer period, based on lek
count data from 1996-2014 (lek count protocols were standardized in
1996 by CPW). Similar to our previous analysis, the long-term data
indicate that, despite slight increases in the past several years, the
satellite populations have declined overall, with the possible
exception of the Cerro Summit-Cimarron-Sims Mesa population, which
appears to be stable or increasing, and Pi[ntilde]on Mesa, with its
highest count since standardized lek counts began in 1996. This topic
is discussed further in the Current Distribution and Population
Estimates and Trends section of this rule.
(5) Comment: CPW stated that the listing proposal does not
acknowledge that male counts from recent lek surveys are at historic
high levels in the Gunnison Basin, and notes that prior to 1996,
surveys lacked a standard protocol and may have had an inconsistent
counting effort.
Our Response: The proposed listing rule stated that the Gunnison
Basin population, while variable, has been relatively stable over the
past 13 years. As the commenter noted, survey data was not standardized
until 1996, making comparisons between current populations and
populations prior to 1996 difficult. If data from 1953-2014 are
considered, the highest lek count occurred in 2006, as shown in Figure
2 in this final listing rule. However, apparent increases in population
size based on lek count data may be the result of increased survey
effort in recent years. Davis (2012, p. 139) noted a sharp increase in
lek areas counted in 1996, when the protocol for lek counts was
standardized in the Gunnison Basin. Therefore, the variation in the lek
counts may reflect a change in survey effort and not a change in
population size. (Also see Davis 2012, p. 143, Figure 5.1, which
displays the increase in lek areas counted beginning around 1996.)
Additionally, Davis (2012, pp. 137-138) and Davis et al. (in press)
indicate that the Gunnison Basin population, although relatively
stable, has declined slightly in recent years, following earlier
increases. These topics are discussed further in the following sections
of this rule: Current Distribution and Population Estimates and Trends;
and Small Population Size and Structure.
(6) Comment: CPW stated that both the PVA described in the RCP
(GSRSC 2005) and the Garton (2005) PVA should be referenced and
considered in the final rule. Another commenter stated that the Garton
(2005) PVA overestimated the species' long-term viability.
Our Response: We describe and evaluate the RCP and Garton PVAs, as
well as that of Davis (2012), in this final rule (see Factor E).
(7) Comment: CPW noted that the proposed rule to list the species
cites the RCP PVA regarding the risk of extinction for small
populations less than 50 birds, but does not explain why several small
populations have persisted at low numbers for decades.
Our Response: The Cerro Summit-Cimarron-Sims Mesa population has
had an estimated population of less than 50 birds for 14 of the past 16
years. The Poncha Pass population has remained at less than 50 birds
from 1999-2014, and lek surveys found no birds in 2013. Poncha Pass is
nearing extirpation, and the Cerro Summit-Cimarron-Sims Mesa population
may also be at risk--with five small leks known in the Cerro Summit-
Cimarron subpopulations and only one lek, which is inactive, in the
Sims Mesa subpopulation. The four remaining satellite populations
generally have population estimates of more than 50 birds, but less
than 500 birds. These four populations would be expected to persist for
a longer period of time than the two smallest populations, but are not
secure from the threats described in this final rule below.
Additionally, as noted in our response to State comment 4, several
smaller populations have been augmented with birds from the Gunnison
Basin population. Without these translocations, the numbers would have
likely been lower for these populations.
As presented in this final rule, based on 1996-2014 lek count data,
a number of the satellite populations are declining. Several population
viability analyses indicate a high extinction risk for all of the
satellite populations (see response to Peer Review comment 31 above).
Our assessment of the current and future threats to these populations
indicates that these trends are likely to continue if the threats are
not addressed. The best available information indicates a reduction of
Gunnison sage-grouse distribution since Euro-American settlement in the
1800s, with evidence of the loss of peripheral populations and a
northward and eastward trend of extirpation (Schroeder et al. 2004, pp.
369, 371, and references therein). These downward trends and historical
losses further indicate the high vulnerability of the satellite
populations to extirpation. These topics are discussed further in the
following sections of this rule: Current Distribution and Population
Estimates and Trends; and Small Population Size and Structure.
(8) Comment: CPW stated that an updated refinement of historical
habitat estimated by Schroeder et al. (2004) is critical to an accurate
assessment of changes in distribution, since they believe this study
likely overestimates the historical range of Gunnison sage-grouse.
Our Response: Historical range estimates from Schroeder et al.
(2004, pp. 370-371) were modified by the RCP (GSRSC 2005, pp. 34-35)
based on more complete information on historical and current habitat
and distribution of the species. We are not aware of any further
refinements to estimates of historical range. Information from Braun et
al. (2014) matches information presented by Schroeder et al. (2004) and
does not add or detract from changes & additions to historical range
presented in the RCP (GSRSC 2005, p. 33-35). Consequently, the RCP
(GSRSC 2005, entire) provides the best available information concerning
the likely historical range of the species. That information indicates
that the Gunnison sage-grouse currently occupies about 8.5 percent of
its potential historical range. Further analysis in this final rule
indicates that approximately 88 to 93 percent of the historical range
of Gunnison sage-grouse has been lost since Euro-American settlement.
While there is some uncertainty in all of these figures, the best
available information indicates there has been a considerable loss of
habitat and a reduction in the range and distribution of Gunnison sage-
grouse. Our listing decision is based on the current status of Gunnison
sage-grouse and the current and future threats to the species and its
habitat. However, the loss of historical range and decline in Gunnison
sage-grouse abundance, and their causes, have contributed to the
species' current status. This topic is
[[Page 69210]]
discussed further in our introduction to Factor A of this rule.
(9) Comment: CPW noted a discrepancy between current occupied range
estimates of 4,720 square kilometers (km\2\) in our 2006 decision and
3,795 km\2\ in the 2013 proposed rule to list the species, which
results in a loss of 925 km\2\ of currently occupied range.
Our Response: Both estimates cite GSRSC (2005). However, the 2006
final listing determination used an initial estimate based on Schroeder
et al. (2004). The 2013 estimate is a refined estimate based on the
GSRSC and CPW data.
(10) Comment: CPW recommended that we rely primarily on Rogers
(1964) to determine historic distribution of the Gunnison sage-grouse,
and noted three citations of Rogers (1964) in the proposed rule to list
the species that should more precisely quote the author. Another
commenter stated that historic distribution estimates by Rogers (1964)
are inferior to Schroeder et al. (2004).
Our Response: Rogers (1964) was written prior to the identification
of Gunnison sage-grouse as a separate species, and summarized overall
sage-grouse distribution in Colorado (including greater sage-grouse)
based on both qualitative and quantitative data and reports from
various sources. This study is informative in that it provides a broad
picture of the species' status, distribution, and trends in Colorado
over time, among other data and information. As such, Rogers (1964) is
considered and cited in this final rule. However, the study did not
conduct a spatial analysis of the species' potential historic range or
the loss of habitat over time, as was done by Schroeder et al. (2004,
entire). Consequently, we concluded it is appropriate to consider and
evaluate this more recent, quantitative study specific to Gunnison
sage-grouse (Schroeder et al. 2004, entire), as modified by GSRSC
(2005, pp. 34-35). We verified information derived from Rogers (1964,
entire) and provided more precise citations in this final rule.
(11) Comment: CPW noted that the Wisdom et al. (2011) standard for
identifying a population stronghold could likely never have been met in
the range of Gunnison sage-grouse, even historically, due to the high
elevation basins and naturally fragmented nature of sagebrush
communities in Colorado.
Our Response: We agree that the distribution of Gunnison sage-
grouse habitat is naturally disconnected due to the presence of
unsuitable habitats such as forests, deserts, and canyons across the
landscape (Rogers 1964, p. 19). This is evident in Figure 18.1 of
Wisdom et al. (2011). The authors combined the occupied and extirpated
ranges of both greater sage-grouse and Gunnison sage-grouse for their
``stronghold'' analysis. Given the much larger range of greater sage-
grouse, with typically larger patches of contiguous sagebrush habitat,
conclusions from the analysis are likely more applicable to greater
sage-grouse. Therefore, in this final rule, we discuss Wisdom et al.
(2011, entire) and its conclusions, but do not further use the term
``stronghold'' because the term, based on the scale of analysis, was
more applicable to greater sage-grouse. This topic and study is
discussed further in our introduction to Factor A in this rule, and
throughout the rule where applicable.
(12) Comment: CPW and others stated that the proposed rule used the
rate of residential development associated with the entirety of
Gunnison County, including the Crested Butte area, and is not
representative of development rates in Gunnison sage-grouse habitats.
Other commenters also noted that human population growth rates have
slowed in recent years leading to slower rates of development. Lastly,
commenters recommended that a single source of human population growth
(such as Colorado Department of Local Affairs) be used. Other
commenters suggested that the human population is increasing.
Our Response: Our estimates regarding human population growth in
the Gunnison Basin in the proposed rule to list the species were
largely based on Colorado Water Conservation Board studies that
included all of Gunnison County, including areas not occupied by
Gunnison sage-grouse, and were derived before the economic downturn (78
FR 2495, January 11, 2013). We recognize that a large portion of
projected human population growth for Gunnison County is expected to
occur outside of Gunnison sage-grouse occupied habitat, such as in the
Crested Butte area and within the City of Gunnison. For this final
rule, we apply current data from the Colorado Department of Local
Affairs to our analysis of human population growth and project
residential development in Gunnison and other counties across the
Gunnison sage-grouse range. For each sage-grouse population area, we
consider total private lands available for development as a proportion
of total occupied habitat, accounting for perpetual conservation
easements that would preclude or limit such development. This analysis
indicates that human populations are expected to continue increasing
across the species' range, but that residential development is a threat
of a low magnitude in the Gunnison Basin now, but is expected to
increase in the future. Residential development is a substantial
current and future threat to the San Miguel, Cerro Summit-Cimarron-Sims
Mesa, and Poncha Pass populations. This topic is discussed further in
the Factor A, Residential Development section of this final rule.
(13) Comment: CPW disagreed with the conclusion in the proposed
rule that roads are a ``major threat'' to the continued existence of
Gunnison sage-grouse and stated that the proposed rule used speculation
from Oyler-McCance et al. (2001) that overstated the threat from roads
and powerlines.
Our Response: In its discussion of roads, the proposed rule stated
that ``Roads within Gunnison sage-grouse habitats have been shown to
impede movement of local populations between the resultant patches,
with road avoidance presumably being a behavioral means to limit
exposure to predation (Oyler-McCance et al. 2001, p. 330).'' The
proposed rule then gave several examples, with additional citations, of
impacts due to roads including: increased disturbance, corridors for
predators, invasion of exotic plants, and resultant avoidance by sage-
grouse. The proposed rule does not cite Oyler-McCance et al. (2001) in
its discussion of powerlines. In this final rule, we describe impacts
from roads and conclude that increased road use and construction will
continue at least through 2050, and is a current and future threat to
the species (see Factor A).
(14) Comment: CPW and one other commenter questioned the use of
Aldridge et al. (2012) regarding nest site selection and urged caution
in applying results across the entire Gunnison Basin, particularly the
firm conclusion that habitat within 2.5 km (1.6 miles (mi)) of roads
and residential developments is unsuitable for the species. CPW also
presented data from a GIS analysis that it conducted.
Our Response: In the proposed rule to list the species, we did not
use 2.5 km (1.6 mi) in any recommendations regarding thresholds for
nest selection; although we did cite papers by Aldridge et al. (2008
and 2011). We agree that some recommendations from the modeling effort
completed by Aldridge et al. (2012) are based on confusing
probabilities regarding selection of nest sites, in particular, the
relationship between relative probability of nest occurrence and
distance to residential development. Figure 5f in Aldridge et al.
(2012) indicates that the probability of nest occurrence is greatest
when the nest is approximately 2.5 km (1.6 mi)
[[Page 69211]]
from development. This probability decreases at both shorter and
greater distances from development; although one would expect the
probability of nest occurrence to continue to increase with increasing
distance from residential development. The variable of residential
density was more intuitive, with the likelihood of nesting decreasing
with increasing residential density. Other variables such as the
proportion of sagebrush cover and road density had more influence on
nest site selection and were also more intuitive. For example, the
probability of nesting decreased abruptly with decreasing sagebrush
cover and with increasing road density. In this final rule, we updated
our older citation (Aldridge et al. 2011); we added a citation
regarding CPW's preliminary GIS analysis of the frequency of successful
and unsuccessful nests at increasing distances from roads (CPW 2013b);
and we do not apply spatial zones of influence to evaluate impacts of
residential development as is discussed in Factor A.
(15) Comment: CPW urged caution in citing Braun (1995), Bui et al.
(2010), and Aldridge and Boyce (2007) regarding impacts from roads due
to the speculative nature of authors' conclusions.
Our Response: We did not cite Braun (1995) or Bui et al. (2010) in
discussions of Factor A, including roads, in the proposed rule or in
this final rule. Aldridge and Boyce (2007) were cited in discussions of
residential development, roads, and nonrenewable energy development.
Related to this comment, when citing Aldridge and Boyce (2007), we
indicate that this and other studies cited were on greater sage-grouse.
However, as discussed in our response to State comment 3 above, due to
similar life histories and habitat requirements between these two
species, we consider information specific to greater sage-grouse as
relevant to Gunnison sage-grouse, a practice followed by the wildlife
and land management agencies that have responsibility for both species
and their habitats.
(16) Comment: CPW and some other commenters questioned the
conclusions regarding powerlines and impacts on Gunnison sage-grouse
from raptor perches and habitat fragmentation.
Our Response: The discussion of powerlines in the proposed rule
provided numerous citations regarding aspects such as raptor perches,
habitat fragmentation, and the spread of invasive plants. Citations
note when the studies were specific to greater sage-grouse. In some
instances, the only information is specific to greater sage-grouse, in
which case, we regard it as the best available information (see our
response to comment 3). We revise our language in this final rule to
clarify usage of the terms habitat loss, degradation, and fragmentation
(see our response to peer review comment 34).
(17) Comment: CPW disagreed with the conclusion in the proposed
rule to list the species that grazing in combination with climate
change and other factors is a threat to Gunnison sage-grouse and
questioned citations from Gregg et al. (1994) and Connelly et al.
(2000a) regarding optimal grass height. CPW also noted a conflict
between critical habitat requirements of grass height of 10-15 cm and
aforementioned citations that recommend grass height of 18 cm or more.
Our Response: In the proposed rule, we concluded that habitat
degradation resulting from improper grazing (described in Factor A in
the proposed rule), particularly with the interacting factors of
invasive weed expansion and climate change, is a threat to Gunnison
sage-grouse persistence. The proposed rule also noted that livestock
grazing may have positive effects on sage-grouse (78 FR 2501, January
11, 2013). Properly managed livestock grazing is not likely to
adversely impact Gunnison sage-grouse. Gregg et al. (1994) described a
study conducted on greater sage-grouse in Oregon and speculated about
potential impacts from livestock grazing. In this final rule, we
clarify that ``Gregg et al. (1994, p. 165) speculated that the
reduction of grass heights due to livestock grazing in sage-grouse
nesting and brood-rearing areas may negatively affect nesting success
when cover is reduced below the 18 cm (7 in.) needed for predator
avoidance.'' Connelly et al. (2000a) was not cited in the grazing
discussion in the proposed rule to list, but was cited in the proposed
rule to designate critical habitat. Seasonally specific primary
constituent elements described in the proposed and final rules to
designate critical habitat include a guideline of 10-15 cm (4-6 in)
grass height based on recommendations in the RCP (GSRSC 2005, p. H-6).
In this final rule, we clarify that recommendations vary for Gunnison
sage-grouse habitat requirements and vegetation characteristics. We
note that Connelly et al. (2000a, p. 977) recommended greater than 18
cm (7 in) grass height for breeding habitats, and that the GSRSC (2005,
p. H-6) (the basis of the critical habitat proposal for breeding
habitats) recommended a grass height of 10-15 cm (3.9-5.9 in).
(18) Comment: CPW noted that the proposed rule to list the species
suggests that livestock trample seedlings, and that this constitutes
competition. CPW stated that they were unaware of any research that has
demonstrated competition between grazers and sage-grouse. One other
commenter stated that Connelly et al. (2004) does not describe
trampling of sagebrush seedlings.
Our Response: Connelly et al. (2004, p. 7-31) states that livestock
trample sagebrush, and provides citations; we note in this final rule
that Connelly et al. (2004) was citing other references. In the
proposed rule, we surmised that livestock may compete directly with
sage-grouse for rangeland resources by consuming forbs and shrubs.
However, as the commenter mentions, this question has not been
researched, and our conclusion is therefore inferred rather than
proven. In this final rule, we deleted specific references to
competition between livestock and sage-grouse. However, we present
evidence that indicates consumption of important vegetation by
livestock negatively affects sage-grouse that use those resources, such
as the reduction of forbs and grasses that may affect chick survival
(see Factor A).
(19) Comment: CPW disagreed with the conclusion and inference that
browsing by big game on mountain shrubs resulted in a negative effect
on Gunnison sage-grouse habitat.
Our Response: This final rule includes a discussion of available
information regarding impacts of wild ungulate herbivory in Gunnison
sage-grouse habitat, including one study (Japuntich et al. 2010, pp. 7-
9) that documented reduced size and vigor of mountain shrubs (not
sagebrush), which could reduce accumulations of drifting snow, which
might in turn reduce the availability of soil moisture for forbs and
grasses. If all of these impacts occurred, nesting and brood-rearing
habitat could be affected. In this final rule, we conclude that the
effects of livestock grazing are likely being exacerbated by intense
browsing of woody species by wild ungulates in portions of the Gunnison
Basin and the Crawford area (see Factor A, Domestic Grazing and Wild
Ungulate Herbivory).
(20) Comment: CPW asserted that the proposed rule relied on
speculation by Braun (1998), Oyler-McCance et al. (2001), and Stevens
(2011) regarding the effects of fences on Gunnison sage-grouse. CPW
also provided additional information regarding research it conducted
that tracked more than 1,000 radio-marked greater sage-grouse and
documented two mortalities from collisions with fences. A follow-up
[[Page 69212]]
letter from CPW also noted four mortalities resulting from collisions
with utility lines. One other commenter stated that fences fragment
habitat.
Our Response: We cite multiple references in Factor A of this final
rule that implicate the potential impacts of fences on Gunnison sage-
grouse. Based on the information provided by CPW specific to Gunnison
sage-grouse, mortalities from collisions with fences and utility lines
are likely minimal, and we have included the information that CPW
provided on strike-related mortalities. We conclude that fences may be
a contributing factor in the species' decline; however, we have no
specific data on the scope of this threat (see Factor A, Fences).
(21) Comment: CPW stated that the Service does not know what the
final measures in the Bureau of Land Management's (BLM) Resource
Management Plans (RMPs) will be concerning travel management, and that
the Service overstates the threat of roads. Consequently, CPW states
that our conclusion that the revised RMPs are inadequate to address
that threat of roads outlined by Aldridge et al. (2012) was premature.
Our Response: We use the best available information to reach our
conclusion in this final rule that roads are a threat to Gunnison sage-
grouse (see Factor A, Roads). The BLM is in the process of amending its
RMPs and we do not know how road issues will be addressed in the
amended plans. Under the Act, we are required to assess the adequacy of
RMPs with respect to relevant threats based on the RMPs as they exist
at the time of this listing decision. Thus, while we conclude that road
impacts can be reduced by regulatory mechanisms, the existing
mechanisms are currently not fully addressing the threat. We recognize
the complexity of threats to Gunnison sage-grouse and the limited
capacity of regulatory mechanisms to address some of those threats. For
example, impacts caused by disease, small population size, or climate
change are not easily addressed by regulatory mechanisms. However,
other impacts such as current and future roads, hunting, grazing, or
development can often be addressed with adequate regulatory mechanisms
(22) Comment: CPW stated that the discussion regarding vegetative
structure guidelines incorporated into management plans and permit
renewals is confusing.
Our Response: We clarify discussions regarding vegetative structure
guidelines in this final rule (see Factor A, Domestic Grazing and Wild
Ungulate Herbivory).
(23) Comment: CPW asserted that the Service did not acknowledge
that Gunnison sage-grouse habitat is highly variable rather than
continuous across the landscape.
Our Response: We acknowledge that Gunnison sage-grouse habitat is
highly variable across the landscape, and we do not consider it to be
continuous currently or historically. We included a discussion of the
naturally disconnected nature of Gunnison sage-grouse habitat in this
final rule (see Factor A).
(24) Comment: CPW and several other commenters suggested that the
Service evaluate structural habitat guidelines recommended in the RCP
with data reported by the BLM and Williams and Hild (2011).
Our Response: The final rule includes conclusions from vegetation
monitoring efforts in the Gunnison Basin conducted by Williams and Hild
in 2010 and 2011. This topic is discussed further in the Domestic
Grazing and Wildlife Herbivory section in Factor A of this final rule.
(25) Comment: CPW presented new information regarding small
populations and inbreeding depression.
Our Response: We include and consider this information in this
final rule. We note that this new information indicates that the San
Miguel Basin Gunnison sage-grouse effective population size is below
the level at which inbreeding depression has been observed to occur
(Stiver et al. 2008, p. 479), and that the authors postulated that the
observed lowered hatching success rate of Gunnison sage-grouse in their
study may be caused by inbreeding depression. Finally, we conclude that
because the remaining Gunnison sage-grouse satellite populations are
smaller than the San Miguel population, they are also likely small
enough to induce inbreeding depression, and could be losing adaptive
potential (see Factor E).
(26) Comment: CPW and two other commenters disagreed with
conclusions in the proposed rule regarding minimum and effective
population sizes, and the amount of habitat needed to support a viable
population.
Our Response: We do not recommend or adopt a specific number for a
minimum viable population size, other than concluding that, based on
the best available information, several of the satellite populations
are trending toward extirpation. With their low absolute and effective
population sizes, the satellite populations are particularly at risk
from stochastic environmental and genetic factors (see Factor E, Small
Population Size). We address the amount of habitat needed to provide
for the conservation of the species in our final critical habitat
determination for Gunnison sage-grouse published elsewhere in today's
Federal Register. In this final rule we also reviewed the three
available PVAs for Gunnison sage-grouse, which applied various
techniques to estimate the viability of populations. Collectively,
these studies and population trends from 1996-2014 indicate that one or
more of the satellite populations may become extinct within the
foreseeable future (see Factor E).
(27) Comment: CPW noted that drought can impact nest success, but
not adult survival, suggesting that Gunnison sage-grouse can
accommodate drought cycles.
Our Response: We agree that adults are less vulnerable to impacts
from drought. Adult survival rates of Gunnison sage-grouse in the
Gunnison Basin were not influenced by drought conditions in 2005 (CPW
2013c, p. 9; Davis 2012, p. 55). However, if a drought persists through
multiple nesting seasons, recruitment will likely be impacted. This
topic is discussed further under the following sections in this final
rule: Drought and Extreme Weather, Small Population Size and Structure,
and Climate Change.
(28) Comment: CPW and CDA noted that at least 79 percent of
occupied habitat in the Gunnison Basin is protected from development,
including government-owned lands, private lands with Conservation
Easements, Candidate Conservation Agreements with Assurances, and/or
similar legal agreements that preclude development to the detriment of
grouse. Therefore, these agencies asserted, the Gunnison Basin is
adequately protected for the conservation of the species.
Our Response: While the conservation and habitat protection efforts
undertaken in the Gunnison Basin are commendable, and help reduce the
impact of development on the species and its habitat, these measures
vary in their capacity to avoid or minimize impacts such as the effects
of habitat decline. Consequently, we were not able to conclude that
Gunnison sage-grouse habitat is adequately protected, despite the
benefits of the various conservation efforts. Conservation efforts and
regulatory mechanisms are evaluated in this final rule.
(29) Comment: CPW, the Utah Office of the Governor, and several
other commenters requested clarification regarding the interpretation
and use of the Significant Portion of Range (SPR) policy.
Our Response: On July 1, 2014, we published a final policy
interpreting the phrase ``Significant Portion of its Range'' (SPR) (79
FR 37578). In
[[Page 69213]]
accordance with that policy, the first step in our analysis of the
status of a species is to determine its status throughout all of its
range. If we determine that the species is in danger of extinction
(endangered), or likely to become so in the foreseeable future
(threatened), throughout all of its range, we list the species as an
endangered or threatened species and no SPR analysis is required. In
this case, we have determined in this rule that the Gunnison sage-
grouse is threatened throughout all of its range, therefore we did not
perform an SPR analysis.
(30) Comment: CPW, CDA, and the Utah Office of the Governor
asserted that speculation in the literature was sometimes portrayed as
science.
Our Response: Under the standards of the Endangered Species Act
(Act), we are required to base our determinations of species status on
the best available information. Our first choice is information from
recent, peer-reviewed publications that is specific to Gunnison sage-
grouse. However, sometimes the only available information may be based
on studies of greater sage-grouse. Additionally scientific data are
sometimes limited, studies are conflicting, or results are uncertain or
seemingly inconclusive. Scientific information includes both empirical
evidence, and expert knowledge or opinion. In this final rule, we
carefully identified and qualified instances of speculation or
hypotheses from past scientific studies and publications.
(31) Comment: CDA noted that agriculture in Colorado generates $40
billion annually, with cattle anticipated to contribute approximately
$3.5 billion to agricultural production in 2013. CDA stated that cattle
production would likely be seriously harmed, should the species be
listed.
Our Response: The Act does not allow us to consider economic
impacts in decisions on whether to list a species, which must be made
solely on the basis of scientific and commercial information related to
the 5 factors in Section 4(a)(1) of the Act. Economic impacts may be
considered in the designation of critical habitat, and are discussed in
our final critical habitat rule. Our final critical habitat
determination for Gunnison sage-grouse is published elsewhere in
today's Federal Register.
(32) Comment: The Utah Office of the Governor noted that the timing
on the proposed rule is based solely on the need to meet a court
approved settlement date, which did not include participation by the
States of Utah or Colorado. Some commenters suggested that more time is
needed for public review.
Our Response: The publication deadline for the proposed rule was
set by a court approved settlement agreement; however, the timeline for
this final rule was initially set according to the statutory
requirements of the Act and has been extended several times by court
order. The Act requires that a final listing rule be published within
one year of the publication of the proposed rule. As allowed by the
Act, however, we extended this statutory deadline by 6 months due to
substantial disagreement regarding the sufficiency or accuracy of
available data relevant to our determination. Invoking this statutory
extension postponed the final listing decision from September 30, 2013
to March 31, 2014. We also re-opened the public comment period several
times. In addition, due to a government shutdown in October 2013 that
caused us to postpone and reschedule public meetings, the court granted
our request for an additional 6 weeks beyond the statutory timeline.
Finally, the court granted our subsequent request for an additional 6
month extension to allow us to consider the possibility that the
species should be listed as threatened rather than endangered, and to
consider whether a 4(d) rule would be appropriate. This action extended
the deadline for this final rule until November 12, 2014.
(33) Comment: The Utah Office of the Governor stated that the
Service's 2010 warranted-but-precluded finding and 2013 proposed rule
to list Gunnison sage-grouse under the Act differs from the 2006
finding that concluded the species was not warranted for listing,
without presentation of any new information that would indicate a
different conclusion is justified. Several commenters asserted that the
decision to list was due to litigation.
Our Response: Litigation resulted in a settlement agreement that
established a schedule for us to submit a proposed rule to list the
species or a finding that listing was not warranted by a date certain.
The litigation had nothing to do with the ultimate decision to list, or
not. The 2006 not-warranted, the 2010 warranted-but-precluded finding,
and the 2013 proposed rule to list the species were based upon the best
scientific and commercial information available at that time. The 2006
finding concluded that the rangewide population was stable to slightly
increasing (71 FR 19961-19962, April 18, 2006). The 2013 proposed
listing rule included information from new studies, 8 additional years
of recent survey information (2006-2013), as well as population data
from 1996-2000, and concluded that the Gunnison Basin population was
relatively stable and the six smaller populations were in decline (78
FR 2488, January 11, 2013). This final rule incorporates additional
information received since publication of the proposed rule. The basis
for our determination in this final rule is provided in the
Determination section of this rule.
(34) Comment: The Utah Office of the Governor and one other
commenter stated that a Federal listing of the species at this time
provides no additional protection or resources from those already in
place and that voluntary cooperation of private landowners will be much
more effective in improving habitat than protections than what may be
afforded by listing and critical habitat designation. The Utah Office
of the Governor also noted that a final regulation providing for a
listing will cause the State to reassess its conservation efforts for
this species, and may result in reallocation of these efforts to other
species.
Our Response: By statute, the Service must list a species if it
meets the definition of threatened or endangered. There is no provision
in the Act that would allow us to decline to list a species that meets
the definition of threatened or endangered if no additional protection
would occur. Moreover, the Act would confer additional protection to
the Gunnison sage-grouse that could help arrest and reverse its
decline. Once listing of the Gunnison sage-grouse becomes effective,
actions authorized, funded or carried out by Federal agencies that may
affect the species will require section 7 consultations under the Act
in all areas occupied by the species. Section 9 prohibitions against
``take'' will further protect the species from human-caused mortality
due to both direct effects and indirect effects such as continued
habitat decline and harassment. We recognize that the voluntary
cooperation of private landowners has improved conservation of the
species in many areas. However, declining population trends indicate
that these efforts have not been able to stabilize rangewide conditions
(habitat and populations) for the species. We maintain that the best
chance for conservation and ultimately recovery of the species will
require both the protections afforded by listing and critical habitat
designation as well as voluntary conservation measures undertaken by
private landowners, with support from the States in accomplishing these
measures.
(35) Comment: The Utah Office of the Governor described efforts of
the San
[[Page 69214]]
Juan Local Working Group, by Federal and State agencies, private
landowners, and universities to address concerns regarding declining
numbers of Gunnison sage-grouse. Similarly, Colorado's Office of the
Governor identified dozens of conservation efforts that have been
carried out in Colorado that they believe address Gunnison sage-grouse.
Our Response: We acknowledge and commend conservation efforts
undertaken in Utah and recognize their importance in a county where
more than 90 percent of occupied habitat is on private lands. We also
commend the conservation efforts undertaken in Colorado by CPW, local
jurisdictions and other entities. This final rule describes many of the
conservation measures, including local, State, and Federal laws and
regulations, conservation easements, the Gunnison Basin CCA, and
enrollment in the Colorado CCAA, that have been undertaken to improve
or protect Gunnison sage-grouse habitat. We have carefully considered
the projects and programs noted by Colorado and Utah in the development
of this final rule.
(36) Comment: The Utah Office of the Governor described Gunnison
sage-grouse population trends in Utah and stated that reliance on
current population figures would be an arbitrary and capricious
application of facts because adequate time has not been allowed to
determine if numbers will return to stable levels following the severe
winter in 2010. In contrast, CPW stated that severe winters are not a
threat to the species.
Our Response: We recognize that there is annual variability in
population numbers for the Gunnison sage-grouse. Consequently, we place
more emphasis on longer-term population trends over a number of years
than on population estimates from any given year. Our analysis
considers Gunnison sage-grouse population trends from 1996 (when lek
count protocols were standardized) through 2013. We do not conclude
that severe winters are a threat to the species.
Comments From Federal Agencies
(37) Comment: We received multiple comments expressing concerns
regarding the long-term viability of the Poncha Pass population, noting
that bird movement between Poncha Pass and the Gunnison Basin is not
likely. One commenter suggested that Poncha Pass and other small
populations may be better managed as satellite populations, rather than
individual self-sustaining populations.
Our Response: We are also concerned about the long-term viability
of the Poncha Pass population, particularly in view of the 2013 lek
count surveys, which did not detect any birds. CPW translocated 17
additional birds from the Gunnison Basin in the fall of 2013, and 10
more in spring of 2014 (CPW 2014e, p.7). Six males were counted in the
Poncha Pass population during the spring 2014 lek count (CPW 2014d,
p.2). This population will likely require repeated augmentations to
avoid extirpation. This topic is discussed further under the following
sections in this final rule: Current Distribution and Population
Estimates and Trends; and Factor E.
(38) Comment: One agency noted that although the proposed rule to
list the species repeatedly states that the effects from grazing are
inconclusive, the final conclusion was that habitat degradation from
improperly managed grazing, particularly with the interacting factors
of invasive weed expansion and climate change, is a threat to the
species. Several commenters recommended that historical grazing
practices be differentiated from improved current grazing practices.
Our Response: The key word in our conclusion in the proposed rule
is ``improperly.'' Livestock grazing that is done in a manner
consistent with local ecological conditions, including soil types,
precipitation zones, vegetation composition and drought conditions, is
not likely to negatively impact Gunnison sage-grouse, and is compatible
with the needs and conservation of the species. See discussion under
Factor A. The final rule also notes that properly managed livestock
grazing may have positive effects on sage-grouse. We also recognize
that maintenance of sustainable grazing practices on private rangelands
can aid in recovery of the Gunnison sage-grouse by discouraging further
conversion of the species' habitat into habitat unsuitable to the
species (i.e., due to development).
(39) Comment: Several commenters noted that the proposed rule might
have overstated the impacts from grazing on Gunnison sage-grouse
habitat as indicated by BLM Land Health Assessments (LHA). A comment
stated that available data may vary by office, and the LHA is only a
snapshot in time; therefore, it cannot indicate trends. Additionally,
grazing is only one of many causal factors on land health. The
commenter also noted that failure to meet indicators for Land Health
Standard 4 (which evaluates ecological indicators for Special Status
Species) may be due to population trends rather than existing habitat
conditions.
Our Response: This final rule recognizes the limitations and
uncertainties associated with LHA and supporting data. Our conclusion
for livestock grazing effects on Gunnison sage-grouse and its habitat
also acknowledges limitations associated with LHA data (see Factor A,
Domestic Grazing and Wildlife Herbivory).
(40) Comment: One commenter recommended we clarify the impact from
different fence types with regard to habitat fragmentation, increased
predator activities, and collisions.
Our Response: This final rule discusses the various factors that
influence fence strike risks. We acknowledge that those risks vary
depending on fence design, landscape topography, and spatial
configuration. In the Factor A discussion of fences, we note that in 10
years of tracking radio-collared sage-grouse in Colorado, CPW has
documented only two fence strike mortalities in Gunnison sage-grouse.
This information suggests that direct mortality of Gunnison sage-grouse
due to fence strikes is low.
(41) Comment: We received a comment requesting that the Service
recognize that fire and fuels treatment projects managed under very
narrow parameters may be a beneficial tool in managing Gunnison sage-
grouse habitat. The commenter also noted that impacts from cheatgrass
on fire regimes in Colorado do not appear to be the same as in the
Great Basin, and suggests that fire has a role to play in rejuvenating
unoccupied or marginal habitats by creating ``micro-mosaics'' that
benefit the species during different portions of its life cycle.
Our Response: The final rule acknowledges that small fires may have
beneficial impacts to Gunnison sage-grouse habitat and concludes that
fire is currently not a threat to the species. It also concludes that
wildfires may become a threat in the future if cheatgrass continues to
expand. Recent research indicates that prescribed fire may be
inappropriate due to the direct loss and fragmentation of the remaining
sagebrush habitat within the species' range, (Baker 2013, p. 8). We
include this information and citation in this final rule (see Factor A,
Fire).
(42) Comment: One commenter expressed concern regarding the
potential effects of climate change to the long-term sustainability of
Gunnison sage-grouse, particularly in the Dove Creek and Dry Creek
areas.
Our Response: We too are concerned about the potential effects of
climate change on Gunnison sage-grouse
[[Page 69215]]
rangewide. The final rule concludes that climate change is currently
not a threat to the species, but is likely to become a threat in the
foreseeable future. Our analysis includes consideration of climate
change projections for the western U.S. A climate change vulnerability
assessment for the Gunnison Basin described the Gunnison sage-grouse as
highly vulnerable to impacts from climate change (TNC et al. 2011, p.
iii). This topic is discussed further under Factor A, Climate Change in
this final rule.
(43) Comment: The United States Forest Service (USFS) suggested
expanding the CCA from Gunnison Basin to other Gunnison sage-grouse
populations on Federal lands. One other commenter expressed concern
regarding a possible expansion of the CCA to areas outside of the
Gunnison Basin.
Our Response: We agree that the CCA could have benefitted Gunnison
sage-grouse in other populations outside of the Gunnison Basin, and
provided a means for Federal land agencies to streamline ESA section 7
requirements associated with their programs and activities. Although
CCAs cannot be implemented for listed species, adoption of a similar
plan that builds on the principles of the CCA is a viable option for
the satellite populations in the future. We also note the BLM is now in
the process of amending all field office resource management plans
within the range of the Gunnison sage-grouse to increase protections
for this species. This effort will likely build on what was included in
the CCA for BLM-managed lands in the Gunnison Basin.
Comments From the Public
(44) Comment: Several commenters asserted that listing the Gunnison
sage-grouse will adversely impact the local economy.
Our Response: The Act does not allow us to consider economic
impacts in decisions on whether to list a species, which must be made
solely on the basis of scientific and commercial information regarding
the 5 factors in Section 4(a)(1) of the Act. However, economic impacts
may be considered in the designation of critical habitat. Our final
critical habitat determination for Gunnison sage-grouse is published
elsewhere in today's Federal Register. As part of the process of
completing the final critical habitat rule, we completed an Economic
Analysis that evaluates the potential economic impacts of designating
critical habitat on transportation, livestock grazing, mineral and
fossil fuel extraction, residential development, recreation,
agriculture, and renewable energy (Industrial Economics, Inc. 2014). We
also completed an environmental assessment pursuant to the National
Environmental Policy Act (NEPA) on the proposed critical habitat
designation that evaluated the affected environment, including
potential economic impacts to the human environment. These are
discussed further in our final critical habitat rule, published
elsewhere in today's Federal Register.
(45) Comment: Several commenters suggested that the Service should
work cooperatively with other Federal agencies, State wildlife
agencies, farm bureaus, and local governments to partner with
landowners on conservation efforts. One commenter asserted that the
Service has no on-the-ground experience with Gunnison sage-grouse
conservation.
Our Response: We encourage partnerships between the Service, other
agencies, and landowners and have worked cooperatively in such
partnership to further Gunnison sage-grouse conservation. In 2005, for
example, we participated in development of the RCP (GSRSC 2005). This
Plan established management guidelines throughout the range of the
species. In 2006, we entered into a CCAA for the Gunnison sage-grouse
with Colorado Division of Wildlife (now CPW). We estimate, in of
December, 2014 when this rule becomes effective, 40 Certificates of
Inclusion (CI) will have been completed for private properties,
enrolling 94,391 ac in four Gunnison sage-grouse populations, although
only roughly 81,156 ac of these acres fall within suitable Gunnison
sage-grouse habitat. We also cooperated with Federal agencies and other
stakeholders in the Gunnison Basin to complete a CCA to promote
conservation of the species in the Gunnison Basin population on Federal
lands. As stated above, our listing decision is based on the best
available scientific information. Accordingly, our focus is on well-
supported, scientific data and information for the species, generally
at a broader scope than is acquired at the local level.
(46) Comment: Several commenters expressed differing views on
whether livestock grazing in Gunnison sage-grouse habitat should be
restricted.
Our Response: We determined that grazing that is inconsistent with
local ecological conditions is a threat to the species, and grazing in
general may have inadvertent effects at a local level (Factor A,
Domestic Grazing and Wild Ungulate Herbivory).
Although grazing on both public and private lands may affect
Gunnison sage-grouse, privately owned lands typically lack a Federal
nexus for section 7 consultations under the Act, in which case grazing
practices would not be affected by the Act unless they were to result
in ``take'' of Gunnison sage-grouse, as prohibited by section 9 of the
Act. However, more than 300 Federal grazing allotments on nearly
405,000 ha (1,000,000 ac) are located within the final critical habitat
designation (Industrial Economics, Inc. 2014, p. 3-1). On Federal
allotments, through the section 7 consultation process, the managing
agency (BLM or USFS) may choose to implement AUM reductions, seasonal
restrictions, rotational grazing, or other changes to minimize impacts
or avoid jeopardy to the species and any adverse modification to
critical habitat. We do not intend to preclude grazing within critical
habitat, but may seek grazing modifications where warranted to promote
the conservation and recovery of the species. We discuss livestock
grazing under Factor A, Domestic Grazing and Wild Ungulate Herbivory in
this final rule.
(47) Comment: Several commenters expressed differing views on
whether energy and mineral development should be further restricted.
Our Response: The Monticello-Dove Creek and San Miguel Basin
populations support numerous mineral and fossil fuel extraction
activities. One wind project and one potash mine are under development
in the Monticello-Dove Creek population. There are no active uranium
mines in Gunnison sage-grouse habitat. Oil and gas extraction occurs on
both Federal and private lands within the species' range. Mineral and
fossil fuel extraction activities on private lands without Federal
mineral rights are unlikely to have a Federal nexus for section 7
consultations under the Act. Existing Federal regulations, such as BLM
RMPs, and State regulations from the Colorado Oil and Gas Conservation
Commission (COGCC) provide some protection to the species and its
habitat. With respect to mineral and energy development projects on
Federal lands or that otherwise have a Federal nexus (e.g., the project
is authorized, funded or carried out by a Federal agency), we may seek
project modifications during ESA section 7 consultations to benefit
Gunnison sage-grouse. We consider current energy and mineral
development a low threat to the species, as discussed under Factor A,
Mineral Development and Renewable Energy Development, in this final
rule.
(48) Comment: Several commenters expressed differing views
regarding the effectiveness of predator control.
Our Response: Predator removal efforts may sometimes provide short-
[[Page 69216]]
term gains in sage-grouse numbers, but predator numbers quickly rebound
without continual control efforts (Hagen 2011, p. 99). The impacts of
predation on greater sage-grouse can increase where habitat quality has
been compromised by anthropogenic activities such as exurban
development and road development (Coates 2007, pp. 154-155; Bui 2009,
p. 16; Hagen 2011, p. 100). This is discussed further under Factor C,
Predation.
(49) Comment: Several commenters stated that conservation efforts
and recovery should focus on public lands.
Our Response: Conservation of the Gunnison sage-grouse will require
collaboration between Federal, State, and local agencies wherever the
species occurs. Federal agencies manage 54 percent of currently
occupied habitat for Gunnison sage-grouse. Although there is an
abundance of public lands within the current range of the Gunnison
sage-grouse, Federal lands alone are insufficient to conserve the
species. Therefore, conservation and recovery efforts limited to public
lands are not sufficient to ensure conservation of the species.
(50) Comment: Some commenters support or oppose development of a
captive breeding program or translocation of Gunnison sage-grouse. One
commenter stated that the State of Colorado does not have the funds
necessary to conduct a long-term captive breeding program.
Our Response: Establishing wild populations from captive-reared
gallinaceous birds is very difficult, expensive, and only rarely
successful; a captive breeding program in Idaho for greater sage-grouse
had only minimal success (GSRSC 2005, p. 181). The CPW started a
captive-rearing program in 2009 to study whether techniques can be
developed to captively rear and release Gunnison sage-grouse. To date,
survival of captive-reared chicks has been low, as we cited in our
proposed rule (78 FR 2518, January 11, 2013). Translocation of wild
Gunnison sage-grouse from Gunnison Basin to other populations has had
some success, although our understanding of translocation contributions
is limited. Without these translocations, current numbers would likely
be lower for these populations. These topics are discussed further
under Scientific Research and Related Conservation Efforts in this
final rule.
(51) Comment: Some commenters suggested that a Gunnison sage-grouse
working group or recovery team should be established.
Our Response: Local working groups including landowners, interested
individuals and groups, local governments, land management agencies,
and State wildlife agencies have developed conservation plans for the
following Gunnison sage-grouse populations: Gunnison Basin, Crawford,
Dove Creek, San Miguel Basin, Monticello, Pi[ntilde]on Mesa, and Poncha
Pass. As a result, all populations with the exception of the Cerro
Summit-Cimarron-Sims Mesa population have conservation plans. Following
the development of these local conservation plans, the RCP (GSRSC 2005,
entire) was developed, which included participation by the BLM, CPW,
NPS, NRCS, USFS, the Service, and Utah Division of Wildlife Resources
(UDWR). The RCP was intended to supplement local plans and provide
guidance to aid in conservation of the Gunnison sage-grouse. Population
targets were recommended for each population. These planning efforts
are discussed in further detail in Factor A of this final rule. We also
discuss future conservation measures for this species below in this
final rule. The Act requires development of a recovery plan in most
cases for endangered and threatened species, which often results in
establishment of a recovery team.
(52) Comment: Some commenters suggested that sagebrush habitat
should be preserved and, when necessary, recovered.
Our Response: Because sage-grouse are obligate users of sagebrush,
preserving and recovering sagebrush habitat is key to sage-grouse
conservation. Other habitat types such as riparian meadows and
agricultural lands may also be important for Gunnison sage-grouse, but
only if they are in close proximity to sagebrush-dominated habitat (75
FR 59808, September 28, 2010). Several Federal agencies as well as CPW
and UDWR continue to work to improve the quality of sagebrush
communities through grazing management, fencing, re-seeding, fuels
management, and other habitat improvement strategies (GSRSC 2005, pp.
214-219). Listing the species and designating critical habitat will
further conserve Gunnison sage-grouse habitat.
(53) Comment: Several commenters noted the importance of open water
and wet meadows and some also suggested that these habitat types should
be re-established in some areas by removal of sagebrush.
Our Response: High quality brood-rearing habitat for Gunnison sage-
grouse includes mesic meadows, springs, seeps, and low vegetation
riparian areas, all dependent on adequate moisture and consequently at
risk in today's changing climate (TNC et al. 2011, p. H-9). Prescribed
burning and mechanical treatments can be used on a small scale to
create a mosaic of small open patches; however, care should be taken to
avoid further fragmentation of sagebrush habitat (GSRSC 2005, pp. 206-
207).
(54) Comment: Some commenters suggested that seasonal closures of
roads and recreation areas should be implemented as appropriate.
Our Response: Closures have been authorized and used by Federal
agencies and counties to protect Gunnison sage-grouse habitat in
several populations (BLM 2013c, attachment 2; Gunnison County Board of
County Commissioners 2013a, Appendix A; NPS 2013, p. 1; USFS 2013, pp.
11 and 14). We evaluate these efforts in this final rule (see Factor A,
Roads, and Factor D).
(55) Comment: One commenter suggested that number of leks, number
of birds on leks, survival rates, and other ecological parameter be
monitored and used as triggers for requiring additional conservation
efforts.
Our Response: The local and rangewide conservation plans include
monitoring plans. The CPW has conducted annual monitoring of these
parameters following a standard protocol since 1996. Monitoring of
habitat conditions, treatment actions, and compliance are an integral
part of the CCAA for Gunnison sage-grouse.
(56) Comment: Several commenters stated that the Gunnison sage-
grouse population in the Gunnison Basin is stable and not at risk of
extinction; consequently, since this is a significant portion of the
species' range, the species is not endangered. One commenter noted that
the six smaller populations did not constitute a significant portion of
the species' range.
Our Response: Please see our response to comment 29 above. We
include an explanation of how we considered and applied the concept of
SPR in this final rule.
(57) Comment: Several commenters expressed various opinions
regarding the stability of the six smaller populations outside of
Gunnison Basin.
Our Response: The six satellite populations are small, all were
generally in decline from 1996 until 2010, and several continue to show
a declining trend. The San Miguel and Pi[ntilde]on Mesa populations are
currently the largest of the satellite populations, with 206 and 182
birds, respectively, in 2014. The Monticello-Dove Creek population
currently has less than 100 birds total. Population estimates in 2014
for what have been the two smallest populations, Cerro Summit-Cimarron-
Sims Mesa and
[[Page 69217]]
Poncha Pass, were 74 and 16, respectively (CPW 2014a, p.1). Based on
lek count-based population estimates, some satellite populations have
increased slightly over the last several years, or intermittently over
time. However, the last 19 years (1996 to 2014) of lek count data as a
whole indicate all the satellite populations are were in decline in
2010. Several of the satellite populations have increased since 2010.
Although population estimates for Pi[ntilde]on Mesa are currently
higher than in any year since 1996, this population has been augmented
with 93 birds from Gunnison Basin since 2010. The Crawford population
has also been augmented, with 73 birds over the same period; and while
the 2014 population estimate of 157 in this population is the highest
since 2006, it is considerably less than the post-1996 high of 270 in
1998.
For all six satellite populations, population estimates from 1996
to 2014 are below population targets (based on a 10-year average), set
forth by the RCP (CPW 2014d, p. 1; GSRSC 2005, pp. 255-302). The RCP
population targets are the number of birds thought necessary to
conserve Gunnison sage-grouse in those population areas (GSRSC 2005, p.
255). Combined, the satellite populations comprise about 16 percent of
the rangewide population of Gunnison sage-grouse and include
approximately 37 percent of rangewide occupied habitat. These topics
are discussed further in Factors A and E of this rule.
(58) Comment: Several commenters stated that lek counts are not
accurate.
Our Response: As described in this final rule (see Current
Distribution and Population Estimates and Trends), lek count data are
the primary means of estimating and monitoring Gunnison sage-grouse
populations. However, sage-grouse populations can fluctuate widely on
an annual basis, and there are concerns about the statistical
reliability of population estimates based on lek counts (CDOW 2009b,
pp. 1-3). Stiver et al. (2008, p. 474) concluded that lek counts likely
underestimate population size. Another study (Davis 2012, p. 136)
indicated that, based on demographic data, lek count indices
overestimate population size. Although lek count data are available
from as early as the 1950's for some populations, lek count protocols
were first standardized and implemented in 1996 (GSRSC 2005, p. 46).
Prior to 1996, lek count data are highly variable and uncertain, and
are not directly comparable to recent population data (Braun 1998, p.
3; Davis 2012, pp. 139, 143). Therefore, for the purposes of evaluating
current population sizes and trends, the analysis in this final rule is
focused on the standardized lek count data from 1996 to 2013. We also
consider other available scientific information regarding Gunnison
sage-grouse populations such as demographic data and population
viability analyses (see Factor E).
(59) Comment: Several commenters recommended that population data
prior to 2001 be evaluated.
Our Response: In the 2010 12-month finding we relied on population
data over the past decade to quantitatively assess recent trends (75 FR
59808, September 28, 2010). The starting point of 2001 was also used
for trend analysis in the 2013 proposed rule (78 FR 2491, January 11,
2013). In this final listing rule, we analyzed population estimates
over a longer period, based on lek count data from 1996-2013. Similar
to our previous analysis, the long-term data indicates that despite
slight increases in the past several years, the satellite populations
have declined overall, with the possible exception of the Cerro Summit-
Cimarron-Sims Mesa population, which appears stable to increasing at
this time.
(60) Comment: Some commenters stated that there are too many
caveats in the rangewide conservation plan to rely on it for
distribution and abundance information.
Our Response: The current distribution of the Gunnison sage-grouse
is thought to be well understood, based on several decades of surveys
and data. Although not conclusive, CPW aerial surveys during 2013 found
no new leks or occupied areas. Nevertheless, current distribution and
abundance data are estimates due to adverse weather, access, and survey
error. Earlier data is further compromised by the use of incomplete
museum records and historical accounts, as well as varying
methodologies and survey intensities. Pre-settlement data is by
necessity an extrapolation based on species accounts and the likely
distribution of suitable habitat. This is the best available
information, and forms the basis of historical and current distribution
and abundance information, as presented in this final rule.
(61) Comment: Some commenters asserted that the Gunnison sage-
grouse is not a separate species from greater sage-grouse.
Our Response: Gunnison sage-grouse and greater sage-grouse were
recognized as separate species in 2000 based on morphological, genetic,
and behavioral differences, and geographical isolation. Consequently,
the American Ornithologist's Union accepted the Gunnison sage-grouse as
a distinct species. Due to the several lines of evidence separating the
two species, we determined in our 2010 12-month finding that the best
available information indicates that the Gunnison sage-grouse is a
valid taxonomic species and a listable entity under the Act (75 FR
59804, September 28, 2010).
(62) Comment: Several commenters stated that habitat fragmentation
and degradation are the main reasons for a steep decline in Gunnison
sage-grouse abundance. One commenter asserted that we overestimated the
impact from fragmentation, and another commenter asserted that habitat
has not been lost or fragmented in the past 50 years.
Our Response: Habitat loss and fragmentation are recognized as
primary causes of the decline in abundance and distribution of sage-
grouse across western North America (Rogers 1964, pp. 13-24; Braun
1998, entire; Schroeder et al. 2004, p. 371), and in Gunnison sage-
grouse across its former range (Oyler-McCance et al. 2001, p. 330;
GSRSC 2005, p. 149; Wisdom et al. 2011, pp. 465-469). Gunnison sage-
grouse depend on sagebrush for their survival and persistence, and the
historical and current distribution of the Gunnison sage-grouse closely
matches that of sagebrush (Patterson 1952, p. 9; Braun 1987, p. 1;
Schroeder et al. 2004, p. 364, and references therein). Current and
future threats described under Factor A of this final rule will further
contribute to habitat loss and decline and, based on historical and
current population trends, a continued decline in the abundance of
Gunnison sage-grouse across its range.
(63) Comment: One commenter noted that there has been no chick
survival in the Miramonte area of the San Miguel population.
Our Response: Although sample size in a study of the San Miguel
Basin (Miramonte subpopulation) was small (eight chicks were studied),
no chicks survived to 30 days of age, meaning no recruitment (survival
of bird from hatching to breeding age) occurred over a 4-year period
(Davis 2012, p. 37). We provide this information in this final rule
(see Predation; and Davis Population Viability Analysis sections).
(64) Comment: Some commenters noted that the bio-geographical
characteristics of the upper Gunnison Basin differ markedly from the
lower Gunnison Basin.
Our Response: There is wide habitat variation within and between
all of the Gunnison sage-grouse populations. We presume this comment is
directed to the idea of population redundancy in the Gunnison Basin.
This topic is discussed
[[Page 69218]]
in Factor E, Small Population Size and Structure, of this final rule.
(65) Comment: One commenter stated that there is no data indicating
the Dove Creek population was within the historical range of the
Gunnison sage-grouse prior to introducing the species to this area in
2010 and 2011.
Our Response: CPW began collecting lek count data from Dove Creek
in 1993, which predates efforts to augment that population. Dove Creek
is included in historical, recent, and current descriptions of the
species' range (Schroeder et al. 2004, pp. 368-371). The 2006 not
warranted finding described the Dove Creek subpopulation as ranging
from 10-358 birds from 1995-2005 (71 FR 19957-19961, April 18, 2006).
(66) Comment: One commenter stated that the Dove Creek population
declined following the 2002-2003 drought and has not yet rebounded.
Our Response: Drought conditions from 1999 through about 2003 (with
residual effects lasting through about 2005) were closely associated
with reductions in the sizes of all populations (CDOW 2009b, entire;
CPW 2013c, p. 9) (see Figures 2 and 3 in this final rule) and lower
nest success (CPW 2013c, p. 2). To date, several of the smaller
satellite populations have not rebounded from declines around that time
(see Figure 3 in this final rule).
(67) Comment: Some commenters stated that conversion to cropland
has not fragmented sagebrush habitat in the past 20-30 years.
Our Response: As stated in this final rule (Factor A, Agricultural
Conversion), except in Gunnison County, the total area of harvested
cropland has declined over the past two decades in all counties within
the occupied range of Gunnison sage-grouse (USDA NASS 2010, entire).
Further, the majority of agricultural land use in Gunnison County is in
hay production, and this has also declined over the past two decades
(USDA NASS 2010, p. 1). We do not have any information to predict
changes in the amount of land devoted to agricultural purposes.
However, because of this long-term trend in reduced land area devoted
to agriculture, we do not expect a significant amount of Gunnison sage-
grouse habitat to be converted to agricultural purposes in the future.
(68) Comment: Some commenters stated that there are no new road
projects; therefore, roads have not increased fragmentation.
Our Response: Roads of all kinds can impact Gunnison sage-grouse
through direct loss of habitat, mortality from collisions, habitat
fragmentation, and habitat degradation. Existing roads will continue to
require maintenance, and usage may increase due to increases in
recreational activities or in the human population. We discuss roads
under Factor A in this final rule.
(69) Comment: Several commenters stated that grazing minimizes
fragmentation by preventing development, conversion to cropland, and
loss of water rights.
Our Response: We agree that livestock grazing operations generally
result in less habitat fragmentation than alternatives such as
residential development, conversion to cropland, mineral and fossil
fuel extraction, or road construction.
(70) Comment: Two commenters noted that ranches are no longer being
subdivided; therefore, fragmentation due to this factor is not
occurring.
Our Response: Exurban development and subdivision of ranches likely
slowed during the recent economic downturn. However, it still occurs,
particularly in the Pi[ntilde]on Mesa and Gunnison Basin populations,
and we expect it to continue into the future in some areas. We discuss
this issue in this final rule (see Factor A, Residential Development).
(71) Comment: Some commenters asserted that the conclusion that
large blocks of sagebrush habitat are needed by Gunnison sage-grouse is
in error because it is based on greater sage-grouse research. Other
commenters stated that not all sagebrush habitat will support Gunnison
sage-grouse.
Our Response: With regard to the first comment, references cited in
the proposed and final rules regarding the need for large expanses of
sagebrush sometimes pertain to greater sage-grouse, but also include
references specific to Gunnison sage-grouse. References specific to
Gunnison sage-grouse that discuss the need for large blocks of
sagebrush habitat include Oyler-McCance et al. (2001, pp. 327-330),
Wisdom et al. (2011, p. 451), and Baker (2013, p. 8). Regarding the
second comment, we agree that not all sagebrush habitat will support
Gunnison sage-grouse. Much sagebrush habitat is outside the current
range of the species or is in patches that are too small in size and
are fragmented, and some sagebrush habitat does not contain the
physical and biological features necessary to sustain the species.
(72) Comment: One commenter stated that Blue Mesa Reservoir
resulted in the largest habitat fragmentation in Gunnison County.
Our Response: Our proposed rule noted the potential impacts of
development of a large irrigation project, but it was not clear that we
were referring to Blue Mesa Reservoir. As clarified in this final rule
(see Factor A, Large Scale Water Development), development of Blue Mesa
Reservoir in 1965 in the Gunnison Basin flooded an estimated 3,700 ha
(9,200 ac), or 1.5 percent of potential habitat for Gunnison sage-
grouse in the Gunnison Basin (McCall 2005, pers. comm.), and according
to Gunnison County (2013a, p. 124), at least one known lek. Based on
the size and location of Blue Mesa Reservoir, we presume that habitat
connectivity and dispersal of birds between the Gunnison Basin
population and satellite populations to the west were impacted.
(73) Comment: One commenter noted that mountain shrub habitat is
used by the Gunnison sage-grouse and therefore, mountain shrub should
not be lumped in with pi[ntilde]on-juniper (Pinus edulis-Juniperus
spp.) habitat.
Our Response: We agree that some deciduous shrub communities
(primarily Gambel oak and serviceberry) are used seasonally by Gunnison
sage-grouse (Young et al. 2000, p. 451). See discussion under Factor A,
Pi[ntilde]on-Juniper Encroachment.
(74) Comment: Several commenters asserted that Gunnison sage-grouse
numbers were highest during a period of higher livestock grazing, and
that there is no negative correlation between grazing intensity and
Gunnison sage-grouse numbers. Other commenters noted either improvement
or degradation of habitat associated with livestock grazing. One
commenter asked what we consider to be a proper grazing regime.
Our Response: Excessive grazing by domestic livestock during the
late 1800s and early 1900s, along with severe drought, significantly
impacted sagebrush ecosystems (Knick et al. 2003, p. 616). Overgrazing
by livestock was cited as one of several contributing factors in the
early loss and deterioration of sagebrush range in the region (Rogers
1964, p. 13). Historical accounts indicate that overgrazing of
sagebrush range in Colorado began around 1875. Overgrazing was
apparently at its worst in the early 1900s and continued until the BLM
was organized in 1934 (Rogers 1964, p. 13). Around 1910, a gradual but
marked decline in sage-grouse numbers and distribution in Colorado had
begun (Rogers 1964, pp. 20-22). This information indicates that
historical livestock grazing practices and overgrazing were a
contributing factor in the early loss and degradation of sagebrush
habitats and initial declines in sage-grouse numbers and distribution.
Although current livestock
[[Page 69219]]
stocking rates in the range of Gunnison sage-grouse are lower than
historical levels (Laycock et al. 1996, p. 3), long-term effects from
historical overgrazing, including changes in plant communities and
soils, persist today (Knick et al. 2003, p. 116). In addition,
widespread use of water developments across the West has since
increased livestock access to sagebrush habitats, and so even reduced
numbers of livestock still pose impacts (Connelly 2004, pp. 7-33, 7-35,
7-92). We know that grazing can have negative impacts to sagebrush and
consequently to Gunnison sage-grouse at local scales. Grazing
inconsistent with local ecological conditions is occurring over a large
portion of the range of the species. Habitat degradation that can
result from grazing practices inconsistent with local ecological
conditions, particularly with the interacting factors of invasive weed
expansion and climate change, is a threat to Gunnison sage-grouse
persistence. See Factor A, Domestic Grazing and Wild Ungulate
Herbivory.
(75) Comment: Several commenters stated that Gunnison sage-grouse
chicks depend on insects in cattle manure.
Our Response: Anecdotal reports and opinion papers (Brunner 2006,
p. 16; Gunnison County 2013a, p. 95) have suggested that cattle manure
attracts and supports insect populations upon which sage-grouse depend
for survival, and that sage-grouse ``follow'' cattle through pastures.
However, there is no evidence to support this theory. Further, there
are no data to substantiate the idea that in sagebrush areas not
actively grazed by livestock, sage-grouse are limited in some way
(Connelly et al. 2007, p. 37). This topic is discussed in Factor A of
this final rule (see Factor A, Domestic Grazing and Wild Ungulate
Herbivory.).
(76) Comment: Several commenters expressed differing opinions on
whether livestock grazing reduces or increases the risk of catastrophic
fire.
Our Response: We know that livestock grazing influences fire
ecology in sage-grouse habitat. However, due to the spatial complexity
of fire in sagebrush ecosystems (Crawford et al. 2004, p. 7), and the
numerous factors that determine the effects of grazing on sagebrush
habitats, the effects of grazing on sage-grouse by altering fire
regimes likely vary widely across time and space. This topic is
discussed in detail in Factor A, Domestic Grazing and Wild Ungulate
Herbivory, of this final rule.
(77) Comment: Several commenters asked what has changed from 2006,
when the Service concluded that grazing was not a threat, to 2013, when
the Service concluded that grazing was a threat.
Our Response: Both the 2006 not warranted determination (71 FR
19954, April 18, 2006) and the 2013 proposed rule to list the species
(78 FR 2486, January 11, 2013) presented similar observations:
Excessive grazing by domestic livestock during the late
1800s and early 1900s, along with severe drought, significantly
affected sagebrush ecosystems, causing long-term impacts that persist
today.
Although we know that historical livestock grazing
practices and overgrazing were a contributing factor in the early loss
and degradation of sagebrush habitats and initial declines in sage-
grouse numbers and distribution, the correlation between historical
grazing and reduced sage-grouse numbers is not exact.
Habitat manipulations to improve livestock forage, such as
sagebrush removal, can affect sage-grouse habitat.
In 2006, we concluded that there was insufficient data to
demonstrate that current grazing was a rangewide threat to the species.
In 2013, several new references related to grazing were available for
consideration (Coates 2007, Hagen et al. 2007, Aldridge et al. 2008,
France et al. 2008, BLM 2008, BLM 2009a, Gunnison County Stockgrowers
2009, Knick et al. 2011, Pyke 2011, Williams and Hild 2011, BLM 2012a).
Our conclusion in 2013 was that habitat degradation can result from
improperly managed grazing, and, particularly with the interacting
factors of invasive weed expansion and climate change, is a threat to
Gunnison sage-grouse persistence. Climate change was not included as a
factor in 2006, but in 2013 we stated that climate change is likely to
become an increasingly important threat to the persistence of Gunnison
sage-grouse. We also noted in our 2013 proposed rule that livestock
grazing can cause local impacts, but population-level impacts are
unlikely. We make the same conclusions in this final rule (see Factor
A, Domestic Grazing and Wild Ungulate Herbivory).
(78) Comment: Some commenters stated that wildlife herbivory needs
to be addressed.
Our Response: In the proposed and final rules, we discuss wild
ungulate herbivory. It occurs throughout the range of the Gunnison
sage-grouse, and there are instances of overgrazing by wild ungulates
on a local level. In this final rule, we note that the effects of
livestock grazing are likely being exacerbated by browsing of woody
species by wild ungulates in portions of the Gunnison Basin and the
Crawford area (see Factor A, Domestic Grazing and Wild Ungulate
Herbivory).
(79) Comment: One commenter noted that very little private or
public land in Dolores County is grazed.
Our Response: More than 81 percent of lands in Dove Creek are
privately owned. We do not have information regarding what percentage
of private lands occupied by Gunnison sage-grouse in Dolores County is
grazed.
(80) Comment: One commenter suggested that grazing should be
reduced or eliminated on public lands.
Our Response: Properly managed livestock grazing is not likely to
impact Gunnison sage-grouse such that it threatens populations or the
species. The BLM and USFS manage grazing allotments on their lands, and
currently consider conservation of Gunnison sage-grouse on many of
their allotments. Allotments occur on approximately 292,000 ha (720,000
ac) or 77 percent of occupied habitat (Industrial Economics, Inc. 2013,
p. 3-1). Stocking rates have declined significantly in recent years.
Both agencies have designated the Gunnison sage-grouse as a ``Sensitive
Species.'' This designation requires the BLM and the USFS to address
the species in their RMPs, and their Land and Resource Management Plans
(LRMPs), respectively. Management actions in these plans include
changes to seasons of use, AUM reductions, rotational grazing, and
other changes to grazing management practices. When the Gunnison sage-
grouse is listed, actions on allotments that might affect the species
will require ESA section 7 consultations under the Act in all areas
occupied by the species. Section 9 prohibitions against ``take'' will
also apply.
(81) Comment: Several commenters asserted that invasive plants such
as cheatgrass and pi[ntilde]on-juniper are not a proven threat to
Gunnison sage-grouse; they have only been proven a threat with greater
sage-grouse. One commenter noted that cheatgrass has increased within
the Gunnison sage-grouse range and is a major threat in the Gunnison
Basin.
Our Response: Cheatgrass can shorten fire intervals in sagebrush
communities. Pi[ntilde]on-juniper encroachment is potential evidence of
extended fire intervals. Either change in fire intervals can adversely
impact habitat for the Gunnison sage-grouse by reducing sagebrush
cover. Based on what is known about the effects of cheatgrass and
pi[ntilde]on-juniper on greater sage-grouse, it is reasonable to infer
their expansion has similar effects on Gunnison sage-grouse. In this
final rule we conclude that neither invasive weeds nor pi[ntilde]on-
juniper encroachment are substantial threats to Gunnison sage-
[[Page 69220]]
grouse at this time, due to their limited extent; however, they are
potential future threats (see Factor A, Invasive Plants and
Pi[ntilde]on-Juniper Encroachment).
(82) Comment: Several commenters stated that drought is causing a
decline in Gunnison sage-grouse numbers; conversely, one commenter
stated that drought is not a threat. Several commenters also stated
that the Monticello-Dove Creek area has degraded Gunnison sage-grouse
habitat due to climate change and drought.
Our Response: The proposed rule to list the species stated that it
is too speculative to conclude that drought alone is a threat to the
species at this time; however, based on rapid species decline in
drought years, it is likely that drought exacerbates other known
threats and thus can negatively affect the species. Drought and
associated effects are discussed further in Factors A and E and
Cumulative Effects From Factors A through E of this rule.
(83) Comment: Several commenters stated that prescribed fire
creates a desirable habitat mosaic, but may also cause a short-term
decline in sagebrush.
Our Response: In Factor A (Fire) of the proposed and final rules we
state that in mesic areas used for brood-rearing, small fires may
maintain a suitable habitat mosaic by reducing shrub encroachment and
encouraging understory growth. However, without available sagebrush
cover nearby, the utility of these sites is questionable.
(84) Comment: Some commenters asserted that climate change is not a
threat because it will not occur within the foreseeable future.
Our Response: Climate change is ongoing and cumulative. The
proposed and final rules conclude that climate change is not a threat
to the Gunnison sage-grouse at this time, but is likely to become a
threat to the persistence of the species over the next 40 years. The
Gunnison sage-grouse was found to be ``highly vulnerable'' to climate
change in the Gunnison Basin (TNC et al. 2011, p. 48).
(85) Comment: Some commenters noted that fire suppression and
reduced fire frequency due to grazing have caused pi[ntilde]on-juniper
encroachment into sagebrush habitat.
Our Response: Pi[ntilde]on-juniper encroachment has been attributed
to the reduced role of fire, the introduction of livestock grazing,
increases in global carbon dioxide concentrations, climate change, and
natural recovery from past disturbance. Most Gunnison sage-grouse
population areas are experiencing low to moderate levels of
pi[ntilde]on-juniper encroachment, although considerable encroachment
has occurred at Pi[ntilde]on Mesa (see Factor A, Pi[ntilde]on-Juniper
Encroachment in All Population Areas). We discuss the relationship
between fire and pi[ntilde]on-juniper encroachment in this final rule
(see Factor A, Fire and Pi[ntilde]on-Juniper Encroachment).
(86) Comment: Some commenters noted that the historical fire
rotation was 178-357 years in Wyoming big sagebrush (A. t.
wyomingensis) and 90-143 years in mountain big sagebrush; these
rotation intervals may or may not be changing.
Our Response: These time periods are from Bukowski and Baker (2013,
p. 5). The authors concluded that fire size, rate of burning, and
severity may be changing due to land-use changes, fire exclusion, and
invasive species such as cheatgrass. Crawford et al. (2004, p. 2)
stated that fire ecology changed dramatically with European settlement.
In high elevation sagebrush habitat, fire return intervals increased
from 12-24 years to more than 50 years, resulting in invasion of
conifers and a resulting loss in shrubs and herbaceous understory; at
lower elevations, fire return intervals decreased dramatically from 50-
100 years to less than 10 years due to invasion by annual grasses. TNC
et al. (2011, p. 12) predicted a trend of higher fire frequency and
severity in the Gunnison Basin due to climate change.
(87) Comment: Two commenters noted that drought has encouraged
invasive plants.
Our Response: Drought can increase the likelihood of some invasive
plants such as cheatgrass out-competing native perennials. The
potential effects of drought and invasive plants on Gunnison sage-
grouse and its habitat are further described in Factors A (Invasive
Plants) and E (Drought) of this final rule.
(88) Comment: One commenter stated that climate change is adversely
affecting Gunnison sage-grouse, but it cannot be mitigated by the
Service.
Our Response: The Service can do little to avert climate change;
however, actions can be taken to minimize specific impacts and improve
the resiliency of species in the face of climate change. For example,
the preferred Gunnison sage-grouse habitat for early brood-rearing
includes riparian areas and wet meadows near sagebrush that provide the
insects and forbs essential for chick survival. These habitat types are
highly vulnerable to impacts from climate change and have been
seriously degraded, but management actions can be taken to maintain and
restore these important habitats (TNC et al. 2011, p. H-9-10).
(89) Comment: One commenter stated that if there are similar trends
in Gunnison sage-grouse populations separated by long distances, the
driver could be climate change.
Our Response: This hypothesis is plausible, although there is no
evidence to support this hypothesis. This final rule discusses the
potential impacts of climate change and drought in Factors A (Climate
change) and E (Drought), and the associated effects on Gunnison sage-
grouse.
(90) Comment: Several commenters stated that predator numbers have
increased and are likely a threat to the Gunnison sage-grouse.
Our Response: Predator populations can increase as a result of
habitat fragmentation and degradation, causing otherwise suitable
habitat to become a population sink for sage-grouse. The best available
information indicates that, as we stated in our proposed rule,
predation is a current and future threat to the species, particularly
in the satellite populations Predation is discussed further under
Factor C in this final rule.
(91) Comment: Several commenters suggested that predator levels
could be managed to relieve the threat from predation.
Our Response: Predator removal efforts sometimes result in short-
term population gains for sage-grouse, but predator numbers quickly
rebound without continual control (Hagen 2011, p. 99). Predation may be
limiting some of the smaller populations of Gunnison sage-grouse, and
in those cases predator control efforts may be appropriate. The best
available information indicates that, as we stated in our proposed
rule, predation is a current and future threat to the species,
particularly in the satellite populations. While predation likely acts
as a threat in localized areas across the range of the species, the
stability of the Gunnison Basin population over the last 19 years
indicates that predation is not having a significant impact on that
population. We believe, however, that the effects of predation are more
pronounced in the satellite populations. Given the stability of the
Gunnison Basin population, we do not believe that the magnitude of this
threat is significant at the rangewide level.While predation is a
threat rangewide, we believe that the effects of predation are
localized and more pronounced in the satellite populations, and
therefore we do not believe that the magnitude of this threat is
significant (see Factor C, Predation).
(92) Comment: Some commenters recommended that we reevaluate our
conclusions regarding nest depredation by elk (Cervus canadensis) and
cattle.
[[Page 69221]]
Our Response: The proposed and final rules document that livestock
can trample nests, either destroying eggs or causing abandonment by
hens. We also cite references that list several species of nest
predators, including elk and domestic cows (see Factor C). However, the
best available information indicates that nest predation by livestock
and elk has negligible impacts on Gunnison sage-grouse at the
population level (See Factor C, Predation).
(93) Comment: Some commenters noted that many predators of Gunnison
sage-grouse are protected and cannot be controlled.
Our Response: Migratory birds such as raptors are protected under
the Migratory Bird Treaty Act (16 U.S.C. 703-712). Take of these
species requires a Federal permit. However, most mammalian predators of
Gunnison sage-grouse and some birds may be controlled. Nevertheless,
predator control efforts will likely only be effective under special
circumstances (see our response to comment 48).
(94) Comment: Some commenters believed that raptor concentrations
associated with powerlines are not evidence of increased predation on
Gunnison sage-grouse, and that perch deterrents are not successful over
the long-term. One commenter provided a paper that summarized studies
regarding sage-grouse and powerlines (EDM International, Inc. 2011).
Our Response: In the proposed and final rules, we present numerous
peer-reviewed studies that have demonstrated an increase in corvids and
raptors associated with powerlines and transmission lines, which we
infer could logically lead to increased predation of sage-grouse. We
discuss these topics further under Factors A (Powerlines) and E
(Predation) in this final rule.
(95) Comment: Some commenters suggested that the risk from the
parasite Tryptmosoma cruzi and the encephalitis virus should be
investigated.
Our Response: In Factor C of this final rule we evaluate the best
available information on diseases in Gunnison sage-grouse and greater
sage-grouse, including West Nile virus, an encephalitis virus lethal to
greater sage-grouse and other gallinaceous birds. We also discuss other
pathogens potentially relevant to Gunnison sage-grouse, based on data
provided by CPW. We are not aware of other scientific information
related to disease in Gunnison sage-grouse. To our knowledge,
Tryptmosoma cruzi is a disease endemic to Latin America and does not
pose a threat to sage-grouse.
(96) Comment: Some commenters stated that there is no evidence that
disease is currently a threat. One commenter noted that there is a low
abundance of the mosquito species that are known vectors of West Nile
virus, and all mosquitos and Gunnison sage-grouse sampled by CPW tested
negative.
Our Response: In the proposed rule, we determined that West Nile
virus is a potential future threat, but it, and other diseases and
parasitic infections, were not considered a current threat. We received
comments from the scientific community expressing concern with this
conclusion, particularly in regard to West Nile virus, based on the
following information: To date, West Nile virus has not been documented
in Gunnison sage-grouse, but is present in all counties throughout the
species' range (USGS 2013, entire). Walker and Naugle (2011, p. 140)
predicted that West Nile virus outbreaks in small, isolated, and
genetically depauperate populations could reduce sage-grouse numbers
below a threshold from which recovery is unlikely because of limited or
nonexistent demographic and genetic exchange from adjacent populations.
Therefore, a West Nile virus outbreak in any Gunnison sage-grouse
population, except perhaps the Gunnison Basin population, could limit
the persistence of that population. This information is discussed
further in Factor C of this final rule.
(97) Comment: One commenter stated that Sovada et al. (1995) does
not support the assertion that red fox and corvid populations are
increasing.
Our Response: We removed this citation from the final rule, because
the study is not relevant to our analysis. Our proposed rule, in error,
stated that Sovada et al. (1995, p. 5) found that ``red fox and
corvids, which historically were rare in the sagebrush landscape, have
increased in association with human altered landscapes.'' However, the
author only speculated that abundance of these species had increased in
sagebrush habitats over time. In this final rule, we discuss how
anthropogenic pressures can influence the diversity and density of
predators based on other studies (see Factor C).
(98) Comment: One commenter stated that predation threats to
Gunnison sage-grouse cannot be presumed to be similar to predation
threats to greater sage-grouse.
Our Response: In the proposed and final rules, we use the best
available scientific and commercial data. We also note that we use
information specific to the Gunnison sage-grouse where available but
still applied scientific management principles for greater sage-grouse
that are relevant to Gunnison sage-grouse management needs and
strategies.
(99) Comment: One commenter asserted that the threat of predation
by raptors is exaggerated.
Our Response: The proposed and final rules state that predation is
the most commonly identified cause of direct mortality for Gunnison
sage-grouse during all life stages and discuss common predators of
adults, juveniles, and eggs. We also present information from
scientific studies that demonstrate the potential impact of raptor
predation on sage-grouse (see Factor C, Predation).
(100) Comment: One commenter noted that in Dolores County at least
one person has contracted West Nile virus, and a significant number of
dead birds have been found.
Our Response: The proposed rule to list the species stated that
there have been no confirmed avian mortalities from West Nile virus in
San Miguel, Dolores, and Hinsdale Counties (78 FR 2519, January 11,
2013). For updates in the final rule, we revisited records from the
Centers for Disease Control (USGS 2013, entire) for West Nile reports
in Colorado and Utah. Those records indicate that a total of 84 dead
wild birds (species other than Gunnison sage-grouse) infected by West
Nile virus have been reported from nine counties within the current
range of the Gunnison sage-grouse since 2002, when reporting began in
Colorado and Utah. In this final rule we conclude that West Nile virus
is a future threat to Gunnison sage-grouse (see Factor C).
(101) Comment: Several commenters stated that conservation
easements, CCAs, and CCAAs protect Gunnison sage-grouse, either
directly or through protection of sagebrush habitat. Varying estimates
of lands under conservation easements were provided, with most
commenters citing the properties and acreages identified in Lohr and
Gray (2013). Other commenters provided estimates of lands enrolled in
the CCAA. Another commenter noted that 17.4 percent of all private
lands in both occupied and unoccupied proposed critical habitat are
protected through either conservation easements or CCAAs. Since 1995, a
commenter reported, private landowners, local, and State expenditures
towards Gunnison sage-grouse conservation exceed $31 million.
Our Response: We applaud these efforts towards Gunnison sage-grouse
conservation. Continuation of conservation efforts across the species'
range will be necessary for conservation and recovery of the species.
Conservation easements and CCAAs
[[Page 69222]]
provide some level of protection for the species from future
development on enrolled lands. In this final rule, we add information
provided in Lohr and Gray (2013), update estimates for lands enrolled
in CCAAs and conservation easements, and consider these conservation
efforts in our listing decision as appropriate (see Factors A and D).
(102) Comment: Several commenters asserted that the current
regulations are either adequate or inadequate to address threats to the
Gunnison sage-grouse.
Our Response: There have been major strides in improving
regulations to protect Gunnison sage-grouse and its habitat. Examples
include Gunnison and Montrose County regulations for land use
permitting in occupied habitat. Nonetheless, for the reasons stated in
Factor D of this rule, existing regulatory mechanisms currently do not
fully address the threat of habitat decline caused by human development
in the species range. In addition, under the Act, the adequacy or
inadequacy of regulatory mechanisms is just one of several factors upon
which our determination to list a species must be based. As described
in the proposed and final rules, there are multiple other threats
contributing to the species' decline rangewide. Therefore, even the
most protective local regulations may be insufficient to address all
threats to the species, or halt recent declines in many of the
populations, such that protection of the species under the Act is not
warranted. In Factor D of this final rule, we evaluate the best
available information related to existing regulatory mechanisms that
address threats to Gunnison sage-grouse and its habitat (Factors A
through C, and E).
(103) Comment: Several commenters stated that the Service should
discuss existing land use policies and regulatory mechanisms with local
governments.
Our Response: The Service has been engaged with Federal agencies,
the States of Colorado and Utah, the Ute Mountain Ute Tribe, affected
counties, and other interested parties throughout the listing process
via letters, emails, telephone calls, meetings, and other means. Verbal
and written comments have been carefully considered and in many
instances incorporated into this final rule.
(104) Comment: Some commenters noted that resources on private
lands are not managed to a lesser standard than resources on Federal
lands.
Our Response: These comments may have been referring to our
assessment of private lands in the grazing section of the proposed
rule. In this final rule (see Factor A, Domestic Grazing and Wild
Ungulate Herbivory), we revise our language to state that we have more
limited information on the extent of grazing, management, and habitat
conditions on non-Federal lands. Although Federal land and livestock
grazing may be more regulated, we cannot make any generalizations about
how habitat conditions in those areas might compare with private lands
where livestock grazing occurs. We note, however, that grazing
allotments containing both Federal and private lands are, in some
cases, managed to meet BLM land health standards through coordination
and cooperation with grazing permittees (BLM 2013c, p. 1-2).
(105) Comment: Some commenters noted that as a designated
``sensitive species'' the BLM must address Gunnison sage-grouse
conservation in their Resource Management Plans and associated activity
plans.
Our Response: We acknowledge that the commenter is correct (see
Factor D, Federal Laws and Regulations).
(106) Comment: Some commenters stated that the COGCC protects
wildlife resources and their habitat.
Our Response: The COGCC implements several environmental
regulations that provide protection to the Gunnison sage-grouse and its
habitat. These regulations generally apply to both Federal and private
lands, although they may conflict with Federal regulations in some
cases. The COGCC classifies all Gunnison sage-grouse occupied habitat
as ``Sensitive Wildlife Habitat'' that requires operators to: (1)
Consult with CPW to evaluate options for minimizing adverse habitat
impacts, (2) educate employees and contractors on conservation
practices, (3) consolidate new facilities to minimize disturbance, (4)
control road access and limit traffic, and (5) monitor wells remotely
when possible. The COGCC also designates lek areas as ``Restricted
Surface Occupancy Areas'' that requires operators to: (1) Comply with
all requirements for ``Sensitive Wildlife Habitat'' and (2) avoid all
new ground-disturbing activities if feasible. The COGCC does not
require these protections in unoccupied habitat (COGCC 2014). We
discuss COGCC regulations in this final rule (see Factor D, State Laws
and Regulations).
(107) Comment: Some commenters noted that parcels of 35 ac (14 ha)
or more are not exempted from State or county oversight.
Our Response: We include this information in this final rule, and
acknowledge that counties have regulatory controls applicable to plus-
35 acre development and projects (see Factor D, Local Laws and
Regulations).
(108) Comment: Some commenters suggested that a PECE analysis
should be conducted.
Our Response: Our Policy for Evaluation of Conservation Efforts
(PECE) is used by the Service when making listing decisions under the
Act. It established criteria for determining when we can consider in
our listing determination future formalized conservation efforts that
have not yet been implemented, or have been implemented, but have not
yet demonstrated whether they are effective at the time of the listing
decision. Numerous conservation actions have already been implemented
for Gunnison sage-grouse, and these efforts have provided and will
continue to provide conservation benefit to the species. These
implemented efforts are considered in the appropriate section of this
rule. Additionally, there are recently formalized future conservation
efforts that intend to provide conservation benefits to the Gunnison
sage-grouse; some of which have not been fully implemented or shown to
be effective. A PECE analysis was conducted by the Service for these
conservation efforts that are too recent to have demonstrated
effectiveness as of this listing determination. This is described
further under Conservation Programs and Efforts Related to Habitat
Conservation. Efforts that are considered regulatory are considered
under Factor D of this rule.
(109) Comment: Two commenters stated that the BLM and USFS must
modify all existing leases and permit allotments in Gunnison sage-
grouse habitat to incorporate enforceable terms and conditions to
protect the species.
Our Response: Current BLM RMPs and USFS LRMPs provide some
regulatory protection for the species. Changes to grazing allotment
management have occurred, consistent with existing RMPs, over the past
10 years as permits have been revised or renewed. The extent to which
appropriate measures to reduce or eliminate other threats to the
species have been incorporated into planning documents or are being
implemented, varies across the species' range and will likely continue
to evolve as a result of BLM's on-going revision of several RMPs in the
species' range and its planned landscape-level, targeted RMP amendments
for the conservation of Gunnison sage-grouse on BLM-administered public
lands in Colorado and Utah (see Factor D, Federal Laws and
Regulations).
[[Page 69223]]
(110) Comment: Some commenters noted that although conservation
easements are voluntary, they are legally binding once they have been
recorded; therefore, they may offer regulatory protection. One
commenter stated that voluntary conservation measures do not constitute
adequate regulatory mechanisms if they are not enforceable and are not
rangewide.
Our Response: We consider conservation easements to be an effective
regulatory tool for the conservation of Gunnison sage-grouse, to the
extent that they permanently limit or restrict land uses for identified
conservation values and purposes and prevent long-term or permanent
habitat loss (see Factor D, Other Regulatory Mechanisms: Conservation
Easements). Other conservation efforts such as the CCA and CCAA are not
considered regulatory mechanisms; and are therefore evaluated in Factor
A, Conservation Programs and Efforts Related to Habitat Protection.
(111) Comment: One commenter suggested that the Land and Water
Conservation Fund could be used to acquire Gunnison sage-grouse
habitat.
Our Response: We agree that this would be a reasonable expenditure
for the Land and Water Conservation Fund. However, there is a backlog
of Federal land acquisition needs, estimated at more than $30 billion,
which could impede timely use of the Fund for this purpose.
(112) Comment: One commenter asserted that conservation agreements
are a violation of Federal and State constitutions.
Our Response: Conservation agreements have been successfully used
by Federal and State agencies for several years to improve the status
of many wildlife species and their habitats; we are not aware of any
instances where they have been found to be unconstitutional, nor do we
have any reason to believe that they are unconstitutional.
(113) Comment: Several commenters stated that oil and gas companies
may cease operations if the Gunnison sage-grouse is listed or critical
habitat is designated for the species. Some commenters asserted that
they have been unable to lease their mineral rights as a result of the
anticipated listing of the species. Several commenters also noted that
a large percentage of county revenues in Dolores and Montezuma Counties
are from oil and gas activities.
Our Response: While restrictions may be placed on various types of
development that are subject to consultation under section 7 of the Act
(on Federal lands or with Federal permitting or funding), the Service
does not intend to preclude mineral or fossil fuel extraction as a
result of listing or designating critical habitat. As noted in our
response to comment 106, the COGCC implements several environmental
regulations on both Federal and private lands that provide some
protection to the Gunnison sage-grouse and occupied habitat. The BLM
generally requires conservation measures on leases it issues. We may
also seek project modifications during section 7 consultations to
benefit Gunnison sage-grouse.
(114) Comment: Some commenters suggested that wind energy
development should be allowed to proceed.
Our Response: The Endangered Species Act contains provisions to
allow development projects to go forward even if they are within
critical habitat or could result in take of a listed species, if those
projects are done in accordance with sections 7 and 10 of the Act. For
a discussion of wind energy development as a threat to the species, see
discussion of Renewable Energy Development in Factor A.
(115) Comment: Some commenters expressed concern that potash mining
in Gunnison sage-grouse habitat may cease operations if the species is
listed or critical habitat designated. RM Potash expressed concerns
that listing may delay their project (Thorson 2013).
Our Response: Potash exploration is planned on BLM lands within
Gunnison sage-grouse unoccupied habitat in San Miguel and Dolores
Counties. The BLM requires operators to adopt conservation efforts
specified in the RMP for this area. These conservation efforts are
required with or without listing the species under the Act. When the
species is listed and critical habitat is designated, section 7
consultation will also be required. The amount of time necessary to
complete a section 7 consultation will vary depending on the complexity
of the project and the anticipated level of impacts to the species. In
this final rule we consider the development of leasable minerals such
as potash a low threat to the species (see Factor A, Mineral
Development).
(116) Comment: Two commenters stated that oil and gas development
threatens some Gunnison sage-grouse populations in San Miguel County.
Our Response: Approximately 13 percent of occupied habitat within
the San Miguel Basin population has authorized Federal leases for oil
and gas development; production is currently occurring on approximately
five percent of this lease area. Currently, 25 gas wells are active
within occupied habitat and 18 additional active wells are immediately
adjacent to occupied habitat. All of these wells are in or near the Dry
Creek subpopulation. In this final rule we consider the development of
leasable minerals such as oil and gas a low threat to the species (see
Factor A, Mineral Development).
(117) Comment: Two commenters suggested that energy companies could
contribute money for Gunnison sage-grouse conservation.
Our Response: Energy companies that pursue development in Gunnison
sage-grouse habitat must follow stipulations provided in the applicable
BLM RMP (if Federal minerals are involved) and comply with applicable
COGCC regulations. The annual costs associated with required
conservation efforts represent a contribution by energy companies.
(118) Comment: One commenter suggested that energy development is
not a threat to the Gunnison sage-grouse because: (1) There is not
adequate information to indicate that renewable energy development is a
threat, and (2) impacts from non-renewable energy development are very
localized.
Our Response: We do not consider renewable energy development to be
a threat to the species at this time (see Factor A, Renewable Energy
Development). As noted in our responses to comment 116, we consider the
development of non-renewable energy (leasable minerals) a low threat to
the species (see Factor A, Mineral Development).
(119) Comment: One commenter asked if power companies will be able
to clear sagebrush under their power lines.
Our Response: The Endangered Species Act contains provisions to
allow projects to go forward even if they are within habitat, critical
habitat or could result in take of a listed species, if those projects
are done in accordance with sections 7 and 10 of the Act. Listed
species, both within and outside of critical habitat, are protected
from take, which includes harming (e.g., shooting, killing, trapping,
collecting) and harassing individual animals. Incidental take that may
result from, but is not the purpose of, otherwise legal activities
without a Federal nexus may be allowed with a permit available from the
Service under section 10 of the Act. Pursuant to section 7 of the Act,
Federal agencies are also required to consult with the Service
regarding any action authorized, funded, or carried out by the agency
that may affect a listed species, both within and outside of critical
habitat, to ensure that the Federal action does not
[[Page 69224]]
jeopardize the existence of any listed species. Sagebrush clearing
under power lines would likely need to be addressed, and effects
minimized, through section 7 or 10 of the Act.
(120) Comment: One commenter suggested that leks in areas of energy
development be relocated.
Our Response: Relocating leks is likely not in the best interest of
the species. Sage-grouse often will continue to return to altered
breeding habitats including leks, nesting areas, and early brood-
rearing areas due to the species' strong site fidelity, despite past
nesting or productivity failures (Rogers 1964, pp. 35-40; Wiens and
Rotenberry 1985, p. 666; Young 1994, p. 42; Lyon 2000, p. 20; Connelly
et al. 2004, pp. 3-4-3-6; Holloran and Anderson 2005, p. 747). Broad-
scale characteristics within surrounding landscapes influence habitat
selection, and adult Gunnison sage-grouse exhibit a high fidelity to
all seasonal habitats, resulting in low adaptability to habitat
changes. A study of greater sage-grouse concluded that strong site
fidelity makes natural re-colonization slow and that anthropogenic
translocations into areas with no resident populations are unlikely to
succeed (Doherty 2008, pp. 80-81). We believe that this conclusion
applies to the Gunnison sage-grouse as well because it exhibits similar
site fidelity characteristics.
(121) Comment: One commenter stated that information regarding
impacts from energy development is based on studies of greater sage-
grouse rather than Gunnison sage-grouse.
Our Response: There is more information available specific to
greater sage-grouse due to the fact that Gunnison sage-grouse was not
recognized as a distinct species until 2000, which means only 14 years
of species-specific research is potentially available. The greater
sage-grouse also has a much broader range, with several states
monitoring and managing the species. The life history and ecology of
the two species are very similar, therefore, with minimal information
available regarding impacts to Gunnison sage-grouse from energy
development, it is reasonable to also consider impacts to greater sage-
grouse from energy development when determining whether or not this
development is a threat to the Gunnison sage-grouse. In this final rule
we do not consider renewable energy development to be a current threat
to the species rangewide; we consider non-renewable energy development
to be a threat of low magnitude to Gunnison sage-grouse (see Factor A,
Mineral Development and Renewable Energy Development).
(122) Comment: One commenter asserted that the Federal government
has put an end to oil and gas drilling throughout the range of the
Gunnison sage-grouse.
Our Response: Of approximately 22,000 ha (54,000 ac) leased by BLM
within Gunnison sage-grouse habitat in Colorado, 38 percent are
currently in production, with 67 active wells. In Utah, approximately
1,100 ha (2,700 ac) are leased within Gunnison sage-grouse habitat,
with none currently in production. On non-Federal lands there are five
active wells in Colorado and three active wells in Utah (Industrial
Economics, Inc. 2013, p. 5-4). Since 2005, the BLM has temporarily
withheld new oil and gas leases from sales throughout occupied Gunnison
sage-grouse habitat in Colorado. However, leases can be sold on
unoccupied habitat, and oil and gas development continues on private
lands.
(123) Comment: Several commenters stated that voluntary
conservation measures and local regulations should be fully considered.
Our Response: We agree. Local regulations and voluntary
conservation measures such as conservation easements, CCAAs, and CCAs
provide formal protection for the Gunnison sage-grouse. We recognize
that such efforts contribute to the conservation of Gunnison sage-
grouse. Under Factor D we evaluate whether threats to the Gunnison
sage-grouse are adequately addressed by existing regulatory mechanisms,
including local regulations, conservation easements, State regulations,
and Federal regulations. CCAAs and CCAs are discussed under Factor A,
Conservation Programs and Efforts Related to habitat Protection.
(124) Comment: Several commenters stated that the DPS analysis
needs to be described in more detail for the seven Gunnison sage-grouse
populations.
Our Response: The term ``distinct population segment'' (DPS) is
included in the definition of species in Section 3(16) of the Act,
which describes a DPS as any species of vertebrate fish or wildlife
which interbreeds when mature. We have a policy that guides our
consideration of DPS issues. In addition to full taxonomic species and
subspecies, a DPS of any vertebrate species is eligible for
consideration for purposes of listing, delisting, or reclassifying. The
authority to list a DPS is to be used sparingly and only when the
biological evidence indicates that such action is warranted. In order
to be considered a DPS, a population must be both discrete and
significant. If a population segment is discrete and significant, it
can be evaluated with regard to whether it is endangered or threatened.
This analysis is different from an SPR (Significant Portion of the
Range) analysis. We considered the entire range of the Gunnison sage-
grouse in our listing evaluation and found that it warranted listing
throughout its range; therefore, there was no need to evaluate
individual population segments for consideration as a DPS. In addition,
we do not believe any biological evidence warrants the listing of any
DPS.
(125) Comment: Several commenters stated that the proposed rules
rely too much on the use of linguistically uncertain or vague wording
to support their conclusions.
Our Response: Natural sciences, including wildlife biology,
typically do not deal in absolutes. Studies seldom evaluate all members
of a species or address all possible variables. Consequently,
conclusions often include wording to address this uncertainty. Tools
such as adaptive management can strengthen the decision-making process
by incorporating new information and adjusting decisions accordingly.
This has occurred with the Gunnison sage-grouse--as more information
has become available, we have adjusted and refined our recommendations
from the proposed to the final rule.
(126) Comment: One commenter stated that if a stressor is not a
threat; the regulatory mechanisms associated with that stressor cannot
be considered a threat.
Our Response: We agree. For example, if hunting is not considered a
threat, then the regulations associated with hunting would not be
considered inadequate. In other instances, it may not be possible to
adequately address a threat through regulatory mechanisms (e.g., small
population size, disease, climate change). We also recognize that
regulatory mechanisms may help reduce impacts of a particular threat
(e.g., residential development in Gunnison County), and yet not fully
address this or other threats to the species.
(127) Comment: Two commenters asserted that tribal concerns have
not been addressed.
Our Response: We have considered tribal concerns in this final
rule. The Service underwent a Government to Government consultation
with the Ute Mountain Ute Tribe regarding the Species Management Plan
developed for the tribal-owned Pinecrest Ranch. This topic is discussed
in detail in Factor A (Conservation Programs and Efforts) of this final
rule.
(128) Comment: Some commenters asserted that initial town hall
meetings
[[Page 69225]]
were not conducted properly because no public meetings were held in
Montezuma County, there was a faulty sound system, too short of a time-
frame for the meeting, poor coordination, and some comments were not
recorded.
Our Response: No public meetings were held in Montezuma County
because no critical habitat was proposed in that county, nor is the
species known to occur in that area. We apologize to anyone who
experienced difficulties in hearing the discussions, did not feel that
adequate time was provided, or felt there was poor coordination between
the Service and local governments. In November, 2013, additional public
hearings were held in Gunnison and Montrose, Colorado; and in
Monticello, Utah to ensure that we provided adequate opportunity for
public comment to occur through our hearing process. In addition,
written comments were accepted during the reopened comment periods.
These processes are discussed in Previous Federal Actions in this final
rule.
(129) Comment: Two commenters asserted that the Service's decision-
making process for listing is influenced by the International Union for
Conservation of Nature (IUCN).
Our Response: The IUCN does not influence our decision-making
process. We provided information on IUCN's ranking of the species for
background only; these assessments are not factored into our analysis
or listing determination in this rule. We make this clarification in
this final rule (see Additional Special Status Information).
(130) Comment: One commenter suggested that the RCP not be
considered in the listing decision because of its questionable legality
and methodology.
Our Response: We believe that the RCP used sound methods which
constituted the best available information at the time. The RCP
specifically states that it is not a legal or regulatory document
(GSRSC 2005, p. 1). Accordingly, we do not consider it a regulatory
mechanism, but do consider it in Factor A as a Conservation Program and
Effort. The plan was developed cooperatively by the BLM, CPW, NPS,
NRCS, USFS, the Service, and UDWR. It was intended to supplement local
conservation plans and provide additional guidance to aid in
conservation of the Gunnison sage-grouse. New research and monitoring
data has been collected since the plan was written; however, we still
regard this as a valuable document. In many instances it provides the
best available information regarding habitat requirements, distribution
and abundance, threats, and current conservation strategies for the
species.
(131) Comment: Some commenters recommended that a range management
school be created to address Gunnison sage-grouse and other issues.
Our Response: In 2006, the Gunnison County Stockgrowers'
Association, supported by a Grazing Lands Conservation Initiative
Grant, organized a training workshop, called Range Management School,
for 37 participants including private ranchers, permittees of Federal
grazing allotments, Federal land managers, and other interested
parties. We support this type of educational program.
(132) Comment: Two commenters suggested that a classification of
``threatened'' is a better approach than a classification of
``endangered.''
Our Response: Based upon the analysis of additional data and new
information received during the comment period, we have concluded that
``threatened'' is the appropriate determination. Our analysis and a
detailed explanation for this determination are presented in this final
rule (see Determination).
(133) Comment: One commenter stated that snowmobiling does not
conflict with lek activities because snowmobiling season ends before
lek activities begin and snowmobiling requires snow depths adequate to
bury sagebrush.
Our Response: Snowmobiling was evaluated as a recreational activity
under Factor E in the proposed rule to list the species. We cited
several sources that identified snowmobiles as one form of recreation
that may be of concern. In this final rule we conclude that
recreational activities in general are not a threat at a rangewide or
population level, but could impact individuals at the local level (see
Factor B).
(134) Comment: Two commenters suggested that overutilization for
scientific research may be a factor in Gunnison sage-grouse declines.
Our Response: We describe mortality risks from scientific research
in the proposed and final rules to list the species and conclude that
the associated mortality rate is low (two percent) and is not a threat
at the population or species level (see Factor B).
(135) Comment: One commenter asserted that chemicals used in
households and farming have affected Gunnison sage-grouse habitat more
than other factors.
Our Response: We evaluate the effects of pesticides, contaminants
associated with non-renewable energy development, and accidental spills
associated with pipelines and transportation corridors in this final
rule. We conclude that none of these posed a threat to the species (see
Factor E, Pesticides and Herbicides).
(136) Comment: One commenter stated that Gunnison sage-grouse are
in an extinction vortex.
Our Response: ``Extinction vortex'' is a modeling term that
describes the process in a declining population where greater rates of
decline occur as the population falls below a minimum viable number and
approaches extinction. This final rule evaluates population trends
across the range of the Gunnison sage-grouse. We determined that this
species is threatened (i.e., likely to become an endangered species
within the foreseeable future throughout all of its range). However, we
do not believe that the species is at this time in an ``extinction
vortex,'' which implies that extinction is inevitable.
(137) Comment: One commenter stated that the number of off-highway
vehicle (OHV) permits issued is not a good indication of the level of
OHV use.
Our Response: The proposed and final rules note that the number of
annual OHV registrations in Colorado increased from approximately
12,000 in 1991 to approximately 131,000 in 2007 (see Factor E,
Recreation). This information is provided simply to note that OHV
activity has increased. Although other factors also should be
considered in determining the level of use by OHVs, an increase of more
than an order of magnitude in registrations from 1991 to 2007 indicates
that the level of use increased during that time period. We conclude
that recreation does not pose a rangewide threat to the species,
although it has the potential to cause individual or local impacts.
(138) Comment: One commenter stated that aircraft-wildlife strikes
pose a risk to aviation.
Our Response: We are not aware of any studies or information
demonstrating that Gunnison sage-grouse collisions with aircraft have
occurred or are a concern.
(139) Comment: One commenter stated that a recovery plan is needed.
Our Response: Recovery Plans are typically drafted after a species
is listed and provide guidance for recovery of threatened and
endangered species and the ecosystems upon which they depend. Section
4(f)(1) of the Act requires the Service to develop and implement these
plans unless a plan will not promote the conservation of a species.
Recovery plans should include: Management actions to conserve the
species; objective, measurable criteria for determining when a species
can be
[[Page 69226]]
removed from the list; and an estimate of the time and cost required to
achieve recovery. We anticipate commencing a recovery planning process
in the near future. Until that time, we are including a conservation
strategy (see Conservation Measures for Gunnison Sage-Grouse Recovery)
in this rule that will provide guidance for conservation efforts in the
interim.
(140) Comment: Several commenters noted specific ongoing projects
or programs that improve Gunnison sage-grouse habitat.
Our Response: We considered the projects and programs noted by the
commenters in making our listing determination and finalizing this
rule. Under Factors A and D in the proposed and final rules to list the
species, we describe many of the conservation measures including local,
State and Federal laws and regulations, conservation easements, the
Gunnison Basin CCA, and enrollment in the Colorado CCAA that have been
undertaken to improve or protect Gunnison sage-grouse habitat.
(141) Comment: Some commenters suggested that the Service
collaborate with the Colorado Farm Bureau (CFB) in Gunnison sage-grouse
management.
Our Response: We welcome input and participation from the CFB and
other organizations. We received a comment letter from CFB that
encouraged continued collaboration between the Service, private
landowners, local and state governments, and others. We agree that
working cooperatively with interested parties will aid in conservation
and recovery of the Gunnison sage-grouse.
(142) Comment: One commenter stated that when landowners enroll
lands in the Conservation Reserve Program (CRP) they often stop
maintaining ponds and wet meadows to the detriment of Gunnison sage-
grouse.
Our Response: We are not aware of any information regarding the
extent of ponds and wet meadows lost following enrollment in the CRP.
We consider enrolled lands, particularly those enrolled under the CRP
State Acres for Wildlife Enhancement initiative, to improve Gunnison
sage-grouse habitat in most cases. The CRP is implemented by the Farm
Service Agency and promotes the conversion of environmentally sensitive
land to long-term vegetative cover. The objectives of the program
include reduction of soil erosion, protection of water resources, and
enhancement of wildlife habitat. Approximately 23,000 ha (57,000 ac) of
Gunnison sage-grouse occupied habitat are currently enrolled in the CRP
(Industrial Economics, Inc. 2013, p. 4-5).
(143) Comment: One commenter stated that wind farms are compatible
with CRP, and wildlife protection.
Our Response: The compatibility of wind farms with CRP as they
relate to Gunnison sage-grouse, and wildlife protection would vary for
each site, depending on the protective measures in place for wildlife,
the location and number of turbines, the type of vegetative cover, and
other variables.
(144) Comment: One commenter stated that no explanation was
provided for why Gunnison sage-grouse are no longer found in Arizona
and New Mexico.
Our Response: We note in the proposed and final rules that a
description of the species' historical distribution was provided in the
2010 12-month finding. In the 12-month finding, we state that much of
what was once Gunnison sage-grouse habitat was lost prior to 1958 (75
FR 59808, September 28, 2010). This included habitat loss throughout
Arizona and New Mexico, as well as portions of Utah and Colorado. We
summarize this information in the Background and Factor A sections of
this final rule.
(145) Comment: One commenter asserted that there is no evidence of
Gunnison sage-grouse movement from Gunnison Basin to other populations.
Our Response: Both the Cerro Summit-Cimarron-Sims Mesa and Crawford
populations are approximately 2 km (1.2 mi) from the Gunnison Basin
population at their nearest points, which is well within movement
distances documented for Gunnison sage-grouse. Sage-grouse require a
diversity of seasonal habitats and are wide-ranging; therefore, they
are capable of making large seasonal movements (Connelly et al. 2000a).
Preliminary data in the Gunnison Basin documented bird movements as
great as 56 km (35 mi) (Phillips 2013, p. 4). Most populations are
currently geographically isolated, with low amounts of gene flow
between populations. However, genetic analysis indicated that a recent
migrant came to the Crawford population from the Gunnison Basin
population; historically, populations were connected through more
contiguous areas of sagebrush habitat (Oyler-McCance et al. 2005).
(146) Comment: One commenter recommended that we distinguish
between smaller distribution power lines and larger transmission power
lines when assessing impacts and planning mitigation.
Our Response: This final rule states that depending on the
infrastructure design, size, location, and other factors, powerlines
can directly affect greater sage-grouse by posing a collision and
electrocution hazard (Braun 1998, pp. 145-146; Connelly et al. 2000a,
p. 974) and can have indirect effects by decreasing lek recruitment
(Braun et al. 2002, p. 10; Walker et al. 2007a, p. 2,644), increasing
predation (Connelly et al. 2004, p. 13-12), fragmenting habitat (Braun
1998, p. 146), and facilitating the invasion of exotic annual plants
(Knick et al. 2003, p 612; Connelly et al. 2004, p. 7-25) (see Factor
A, Powerlines). However, we have no information to precisely measure
how powerlines and transmission lines vary in design or distribution
across the range of Gunnison sage-grouse, and how those effects might
vary across time and space.
(147) Comment: One commenter asserted that the proposed rules
dismissed information provided by CPW.
Our Response: In the proposed and final rules, we consider all
information provided by CPW, and reference that information as
appropriate throughout the rules.
(148) Comment: One commenter recommended citing Davis (2012)
regarding nest success.
Our Response: In this final rule (see Factor E, Effective
Population Size and Population Viability Analyses), we include a
thorough discussion and evaluation of Davis's (2012) findings,
including observed differences in nest success between populations.
(149) Comment: Several commenters stated that we should not
interfere in CPW's management of Gunnison sage-grouse.
Our Response: We recognize the proactive management of Gunnison
sage-grouse by CPW and continue to work with this agency for the
species' conservation. However, our analysis in this final rule
indicates that Gunnison sage-grouse meets the definition of a
threatened species; therefore, we must list it under the Act.
(150) Comment: One commenter noted that historical Gunnison sage-
grouse habitat on BLM land in the Sims Mesa area has been severely
damaged by sagebrush removal.
Our Response: Sagebrush removal on Sims Mesa may have contributed
to the one known lek there being currently inactive. Sage-grouse have
an obligate relationship with sagebrush. The original distribution of
sage-grouse closely followed that of sagebrush. Loss, fragmentation,
and degradation of this habitat is a major threat and a primary reason
for listing the species and
[[Page 69227]]
designating critical habitat. If alteration of sagebrush habitat
continues, remnant populations may become extirpated.
(151) Comment: One commenter noted that there is not adequate data
available to determine whether recent declines of Gunnison sage-grouse
observed by Davis (2012) in the Gunnison Basin are short-term
population fluctuations or the beginning of a long-term decline.
Our Response: We agree. This concern supports the importance of
continued monitoring and conservation of Gunnison sage-grouse
populations. This study is discussed and evaluated in detail in Factor
E of this final rule. We believe, however, that the threat from
residential development in the Gunnison Basin will increase in the
future. Habitat fragmentation and disturbance from new roads,
powerlines, fences, and other infrastructure are also likely to
increase (see Factor A). Additionally, climate change is likely to
increase the threats from drought and West Nile Virus in the future
(discussed further in Factors A, C, and E). Thus, these future threats
must be considered along with the results of the Davis (2012) study.
(152) Comment: One commenter asked if grazing will be considered
``take.''
Our Response: Whether a particular activity will result in ``take''
is determined on a case-by-case basis. Grazing practices that could
result in take can be addressed through ESA section 7 or section 10
processes as applicable, including appropriate review under the terms
of the Gunnison Basin Candidate Conservation Agreement.
(153) Comment: Some commenters noted that all of the affected
county governments have taken the following actions:
Participation in a Memorandum of Understanding,
Signatories to the Conservation Agreement,
Formally committed to adopting a Habitat Prioritization
Tool, which will better predict preferred habitat for the species, and
Formally committed to updating and adopting an amended
Rangewide Conservation Plan.
Our Response: We considered this information in this final rule
(see Factor D, Local Laws and Regulations).
(154) Comment: Some commenters asserted that many of the peer
review comments do not support listing.
Our Response: We requested comments from appropriate and
independent individuals with scientific expertise based on their review
of the proposed rules to list the Gunnison sage-grouse and to designate
critical habitat for the species. We received numerous comments back
from these individuals; some in agreement, some disagreements, and many
suggestions for improving the proposed rules. Substantive comments are
discussed above in the Peer Reviewer Comment section. We considered all
of these comments and incorporated many of their suggestions into this
final rule.
(155) Comment: One commenter expressed concern that hang gliding
and paragliding could be impacted by listing.
Our Response: In this final rule, we conclude that recreational
activities are not a threat at a rangewide or population level, but
could impact the species at a local level (see Factor E, Recreation).
Nevertheless, for those projects and activities with a Federal nexus,
project and activity modifications may be requested by the Service
through the section 7 consultation process to limit impacts on Gunnison
sage-grouse, as necessary.
(156) Comment: One commenter noted that most of the mineral
ownership is severed from surface ownership within the range of the
Gunnison sage-grouse.
Our Response: In this final rule we note that the BLM has
regulatory authority for oil and gas leasing on Federal lands and on
private lands with split-estate, or Federal mineral estate (see Factor
D, Federal Laws and Regulations).
Summary of Factors Affecting the Species
Section 4 of the Endangered Species Act (16 U.S.C. 1533), and its
implementing regulations at 50 CFR part 424, set forth the procedures
for adding species to the Federal Lists of Endangered and Threatened
Wildlife and Plants. Under section 4(a)(1) of the Act, we may list a
species based on any of the following five factors: (A) The present or
threatened destruction, modification, or curtailment of its habitat or
range; (B) overutilization for commercial, recreational, scientific, or
educational purposes; (C) disease or predation; (D) the inadequacy of
existing regulatory mechanisms; and (E) other natural or manmade
factors affecting the species' continued existence. Listing actions may
be warranted based on any of the above threat factors, singly or in
combination.
Below, we carefully assess the best scientific and commercial
information available regarding the past, present, and future threats
to Gunnison sage-grouse. We consider all such information in analyzing
the five factors identified in section 4(a)(1) of the Endangered
Species Act to determine whether Gunnison sage-grouse meets the
definition of an endangered or threatened species.
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
In this section, we evaluate various factors influencing the
decline of sagebrush and important sage-grouse habitats. The term
habitat decline includes any quantitative or qualitative degradation of
habitat by area, structure, function, or composition (Noss et al. 1995,
pp. 2, 17). In this rule, we collectively refer to habitat loss,
degradation, and fragmentation as `habitat decline'. There are varying
interpretations of the term habitat decline, and various methods for
measuring or evaluating it. In this rule, we apply the following
general concepts and definitions to our analysis. Habitat loss or
destruction (such as sagebrush conversion) includes the permanent or
long-term reduction of habitat and generally occurs at smaller scales.
Habitat degradation includes the reduction of habitat quality or
characteristics and generally occurs at smaller scales. Habitat
fragmentation, or the breaking apart of contiguous habitat, occurs at
larger or landscape scales, often as the result of cumulative loss and
degradation of habitat over space and time. In this final rule, we
provide information indicating each of these processes has occurred
across Gunnison sage-grouse range, though those processes may vary over
time and space. Consequently, effects at the individual, population,
and species levels due to habitat decline are variable and not always
certain.
Habitat loss and fragmentation are recognized as primary causes of
the decline in abundance and distribution of sage-grouse across western
North America (Rogers 1964, pp. 13-24; Braun 1998, entire; Schroeder et
al. 2004, p. 371), and in Gunnison sage-grouse in Colorado, Utah, and
across their former range (Oyler-McCance et al. 2001, p. 330; GSRSC
2005, p. 149; Wisdom et al. 2011, pp. 465-469). Gunnison sage-grouse
depend on sagebrush for their survival and persistence, and the
historic and current distribution of the Gunnison sage-grouse closely
matches that of sagebrush (Patterson 1952, p. 9; Braun 1987, p. 1;
Schroeder et al. 2004, p. 364, and references therein). Habitat
fragmentation resulting from human development patterns is especially
detrimental to Gunnison sage-grouse because of their dependence on
large
[[Page 69228]]
expanses of sagebrush (Patterson 1952, p. 48; Connelly et al. 2004, p.
4-1; Connelly et al. 2011a, p. 72) and more contiguous sagebrush
habitats (Rogers 1964, p. 19; Wisdom et al. 2011, pp. 452-453). In
addition, female Gunnison and greater sage-grouse exhibit strong site
fidelity to nesting locations (Connelly et al. 1988; Young 1994; Lyon
2000, Connelly et al. 2004, Holloran and Anderson 2005, Thompson 2012).
Sage-grouse often will continue to return to altered breeding habitats
(leks, nesting areas, and early brood-rearing areas), despite any past
failures in nesting or productivity (Rogers 1964, pp. 35-40; Wiens and
Rotenberry 1985, p. 666; Young 1994, p. 42; Lyon 2000, p. 20, Connelly
et al. 2004, pp. 3-4 to 3-6; Holloran and Anderson 2005, p. 747).
Consequently, there may be lags in the response of sage-grouse to
development or habitat changes, similar to those observed in other
sagebrush obligate birds (Harju et al. 2010, entire; Wiens and
Rotenberry 1985, p. 666).
The distribution of sage-grouse habitat is naturally disconnected
due to the presence of unsuitable habitats such as forests, deserts,
and canyons across the landscape (Rogers 1964, p. 19). However, the
onset of Euro-American settlement in the 1800s resulted in significant
human alterations to sagebrush ecosystems throughout North America,
primarily as a result of urbanization, agricultural conversion, and
irrigation projects (West and Young 2000, pp. 263-265; Miller et al.
2011, p. 147). Areas in Colorado that supported basin big sagebrush
were among the first sagebrush community types converted to agriculture
because their soils and topography are well-suited for agriculture
(Rogers 1964, p. 13). Decreases in the abundance of sage-grouse
paralleled the loss of range (Braun 1998, pp. 2-3), and a gradual but
marked decrease in sage-grouse distribution and numbers in Colorado had
begun around 1910 (Rogers 1964, pp. 20-22). Our listing decision is
based on the current status of Gunnison sage-grouse and the current and
future threats to the species and its habitat. However, the loss of
historical range and decline in abundance, and the associated causes of
those declines, have contributed to the species' current precarious
status. Further, historical information can be evaluated to help
forecast how populations and the species may respond to current and
future threats.
Based on historical records, museum specimens, and potential
sagebrush habitat distribution, the potential historic range of
Gunnison sage-grouse was estimated to be 21,376 square miles, or
13,680,590 ac (GSRSC 2005, pp. 32-35, as adapted from Schroeder et al.
2004, entire). This range included parts of central and southwestern
Colorado, southeastern Utah, northwestern New Mexico, and northeastern
Arizona (Schroeder et al. 2004, pp. 368, 370). However, only a portion
of this historical range would have been occupied at any one time. The
species' estimated current range is 1,822 square miles, or 1,166,075
ac, in central and southwestern Colorado, and southeastern Utah (Figure
1) (GSRSC 2005, pp. 32-35, as adapted from Schroeder et al. 2004,
entire). Based on these figures, the species' current range represents
approximately 8.5 percent of its historical range (GSRSC 2005, p. 32).
Similarly, Schroeder et al. (2004, p. 371) estimated the species'
current overall range to be 10 percent of potential presettlement
habitat (prior to Euro-American settlement in the 1800s). As estimated
in our final rule to designate critical habitat for Gunnison sage-
grouse published elsewhere in today's Federal Register, the species'
current potential range includes an estimated 1,621,008 ac in
southwestern Colorado and southeastern Utah, comprised of 923,314 ac
(57 percent) of occupied habitat and 697,694 ac (43 percent) of
unoccupied habitat. Based on these figures, the current potential range
of 1,621,008 ac represents approximately 12 percent of the potential
historic range of 13,680,640 ac. The estimates above indicate that
approximately 88 to 93 percent of the historical range of Gunnison
sage-grouse has been lost since Euro-American settlement. We
acknowledge that these estimates are uncertain and imprecise.
Nevertheless, the best available information indicates a reduction of
Gunnison sage-grouse distribution since Euro-American settlement in the
1800s, with evidence of the loss of peripheral populations and a
northward and eastward trend of extirpation (Schroeder et al. 2004, pp.
369, 371, and references therein). This contraction in the birds' range
indicates the vulnerability of all the populations to extirpation.
In southwestern Colorado, between 1958 and 1993, an estimated 20
percent (155,673 ha (384,676 ac)) of sagebrush was lost, and 37 percent
of sagebrush plots examined were fragmented (Oyler-McCance et al. 2001,
p. 326). Another study estimated that approximately 342,000 ha (845,000
ac) of sagebrush, or 13 percent of the pre-Euro-American settlement
sagebrush extent, were lost in Colorado, which included both greater
sage-grouse and Gunnison sage-grouse habitat (Boyle and Reeder 2005, p.
3-3). However, the authors noted that the estimate of historic
sagebrush area used in their analyses was conservative, possibly
resulting in an underestimate of historic sagebrush losses (Boyle and
Reeder 2005, p. 3-4). Within the range of Gunnison sage-grouse, the
principal areas of sagebrush loss were in the Gunnison Basin, San
Miguel Basin, and areas near Dove Creek, Colorado. The authors point
out, however, that the rate of loss in the Gunnison Basin was lower
than other areas of sagebrush distribution in Colorado. At that time,
the Gunnison Basin contained approximately 250,000 ha (617,000 ac) of
sagebrush and areas of riparian aspen forest, mixed-conifer forest, and
oakbrush (Boyle and Reeder 2005, p. 3-3). Within the portion of the
Gunnison Basin currently occupied by Gunnison sage-grouse, 170,000 ha
(420,000 ac) is composed exclusively of sagebrush vegetation types, as
derived from Southwest Regional Gap Analysis Project (SWReGAP)
landcover data (multi-season satellite imagery acquired 1999-2001)
(USGS 2004, entire).
Sagebrush habitats within the range of Gunnison sage-grouse are
becoming increasingly fragmented as a result of various changes in land
uses and the expansion in the density and distribution of invasive
plant species (Oyler-McCance et al. 2001, pp. 329-330; Schroeder et al.
2004, p. 372). Based on spatial modeling, a variety of human
developments including roads, energy development, residential
development, and other factors known to cause habitat decline were
correlated with historical loss of range and extirpation of Gunnison
and greater sage-grouse (Wisdom et al. 2011, pp. 465-468). This model
indicated that no ``strongholds'' (secure areas where the risk of
extirpation appears low) of occupied range are evident for Gunnison
sage-grouse (Wisdom et al., 2011, p. 469). Landscapes containing large
and contiguous sagebrush patches and sagebrush patches in close
proximity had an increased likelihood of sage-grouse persistence
(Wisdom et al. 2011, p. 462).
In this final rule, we discuss Wisdom et al. (2011, entire) and its
conclusions, but do not use the term ``stronghold.'' Nevertheless,
consistent with Wisdom et al. (2011, entire) and numerous other studies
noted above, we maintain that the persistence of Gunnison sage-grouse
is dependent on large and contiguous sagebrush habitats, that human
development and disturbance contribute to the decline of this needed
habitat, and that such impacts negatively affect the survival and
persistence of Gunnison sage-grouse.
[[Page 69229]]
The degree to which habitat fragmentation prevents a species'
movement across the landscape depends, in part, on that species'
ability to move large distances and thereby adjust to changes on the
landscape. Sage-grouse are wide-ranging and capable of making large
seasonal movements, because they require a diversity of seasonal
habitats (Connelly et al. 2000a, pp. 968-969, and references therein).
Movements of Gunnison sage-grouse as great as 56 km (35 mi) have been
documented in the Gunnison Basin (Phillips 2013, p. 4). In contrast,
the maximum recorded movement distance of Gunnison sage-grouse in the
Monticello population is 8.2 km (5.1 mi), associated with winter
movement (Ward 2007, p. 15). Prather (2010, p. 70) noted that such
behavior may be due to the presence of large areas of pi[ntilde]on-
juniper (i.e., less suitable habitats) which bracket currently occupied
habitat in the Monticello population area.
Population dynamics of greater sage-grouse in northwestern Colorado
functioned at much smaller scales than expected for a species capable
of moving large distances (Thompson 2012, p. 256). The majority of
juvenile dispersal was intra-population movement (within one breeding
population), with only one inter-population movement (between separate
breeding populations) observed during one study (Thompson 2012, p.
169). As a result, juvenile recruitment into home breeding ranges
ranged between 98 and 100 percent (Thompson 2012, p. 170). Based on
observed bird dispersal in that study, gene flow and connectivity can
likely be maintained for populations within 5 to 10 km (most dispersals
were less than 10 km) and possibly as far as 20 km (the maximum
dispersal distance of one of the subpopulations studied) in greater
sage-grouse (Thompson 2012, p. 285-286). The populations of greater
sage-grouse studied were within areas where birds are known for moving
between populations.
Because individual movement patterns likely vary by population and
area, their susceptibility to habitat loss and degradation may also
differ. We expect that where habitat is already more limited (quantity
and quality) and isolated, such as in the six satellite populations,
habitat loss and decline will have more serious consequences in terms
of population fitness and survival. Where habitat is already severely
limited or degraded, or where sage-grouse populations are small, any
loss of habitat may impact those populations. In addition, habitat loss
impacts are expected to be greater in important and/or limiting
seasonal habitats, such as areas used during moderate to severe
winters, or in lekking, nesting, or brood-rearing habitats (GSRSC 2005,
p. 161).
The loss of leks or the decline of nesting or brood-rearing
habitats can have serious consequences for sage-grouse population
viability by reducing reproductive success and recruitment (survival of
young to breeding age). Limitations in the quality and quantity of
nesting and early brood-rearing habitats, in particular, are especially
important because Gunnison sage-grouse population dynamics are most
sensitive during these life-history stages (GSRSC 2005, p. G-15).
Juvenile recruitment is one of the most important demographic factors
influencing or limiting sage-grouse population growth rates and
viability (Connelly et al. 2004, p. 3-11, GSRSC 2005, p. 173). In a
recent demographic and population viability study of Gunnison sage-
grouse, juvenile survival was found to be the most influential vital
rate in the Gunnison Basin population, which is currently a relatively
stable population (Davis 2012).
Brood-rearing habitat must provide adequate cover adjacent to areas
rich in forbs and insects to assure chick survival during this period
(Connelly et al. 2000a, p. 971; Connelly et al. 2004, p. 4-11). Late
brood-rearing habitats (also referred to as summer-fall habitats) may
include riparian areas, wet meadows, and irrigated fields that provide
an abundance of forbs and insects for hens and chicks (Schroeder et al.
1999, p. 4; Connelly et al. 2000a, p. 980). In northwest Colorado,
dispersal, migration, and settlement patterns of juvenile greater sage-
grouse--factors important to population persistence--were more
influenced by limitations associated with local traditional breeding
(lek) and brood-rearing areas than by landscape-level vegetation
structure and composition (i.e., the spatial distribution and
configuration of vegetation types) (Thompson 2012, pp. 317, 341). The
same study recommended restoration, creation, and protection of early
and late brood-rearing habitats to increase chick survival rates
(Thompson 2012, p. 135). The importance of brood-rearing habitat for
juvenile survival, recruitment, and hence, population viability of
sage-grouse is evident. These key habitats are particularly susceptible
to drought (see Factor E, Drought) and predicted climate change effects
(The Nature Conservancy 2011, p. 11) (see Climate Change in this Factor
A analysis).
As presented above, habitat decline, including loss, fragmentation,
and degradation of quality, has known adverse effects on Gunnison sage-
grouse populations. Gunnison sage-grouse depend on sagebrush for their
survival and persistence, and the historical and current distribution
of the Gunnison sage-grouse closely matches that of sagebrush
(Patterson 1952, p. 9; Braun 1987, p. 1; Schroeder et al. 2004, p. 364,
and references therein). Approximately 88 to 93 percent of the species'
former range has been lost since the 1800s (see discussion above), and
much of the remaining habitat is degraded or fragmented (Oyler-McCance
et al. 2001, p. 326; Oyler-McCance et al. 2001, pp. 329-330; Schroeder
et al. 2004, p. 372; Wisdom et al., 2011, p. 469). Future habitat loss
will have greater impacts in seasonally important habitats and in
smaller populations where available habitat is already limited (GSRSC
2005, p. 161). As described later in this section, many of the factors
that result in habitat decline may be amplified by the effects of
climate change, thereby influencing long-term population trends. The
following sections examine factors that can result in or contribute to
habitat decline to evaluate whether they, individually and
cumulatively, threaten Gunnison sage-grouse.
Residential Development
In our proposed rule to list Gunnison sage-grouse as endangered (78
FR 2486, January 11, 2013), we determined habitat loss and
fragmentation from residential development to be a principal threat to
Gunnison sage-grouse conservation. We received numerous comments and
new information from the scientific community, government agencies, and
other entities related to residential development in the range of
Gunnison sage-grouse. Many of the comments we received suggested that
our initial analysis incorrectly applied scientific and other
information related to residential development and its effects, likely
overestimating its threat to the species, particularly in relation to
the Gunnison Basin area.
In light of these comments, in this final rule, we reevaluate the
threat of residential development to Gunnison sage-grouse. First, we
evaluate scientific information related to effects of residential and
infrastructural development on sage-grouse and sagebrush habitats in
general, including studies specific to Gunnison sage-grouse where
available. Second, we discuss human population growth and residential
development trends and projections across the broader Rocky Mountain
region. Finally, we assess the impact of current and future human
population growth and residential development rangewide and within the
[[Page 69230]]
individual Gunnison sage-grouse populations. As in the proposed listing
rule, much of our analysis here is focused on the current and potential
future effects of residential development and habitat loss in the
Gunnison Basin, since it contains the vast majority of occupied habitat
and Gunnison sage-grouse.
The level of habitat loss due to residential development varies
widely across the seven populations of Gunnison sage-grouse. Federal
land ownership of occupied habitat in some populations reduces the
potential impact of residential development, which largely occurs on
private lands. Conversely, portions of occupied habitat in private
ownership may predispose some sage-grouse populations to greater
impacts due to higher levels of development (GSRSC 2005, p. 160). As
described in the following sections, current and future human
population growth rates and patterns also vary widely across the
species' range. Concentration of residential growth in or near
municipal and other areas outside of occupied or suitable habitat will
likely avoid or minimize impacts, while rural and exurban development
in occupied habitat will likely increase impacts on the species.
Other factors may also affect the impact of residential development
on Gunnison sage-grouse populations or habitat. These factors include,
but are not limited to, the extent and density of already developed
land and existing infrastructure, changes in future patterns of
residential growth, new or additional development of infrastructure
(e.g., roads, powerlines, irrigation) associated with human population
growth, the site-specific quality or quantity of suitable habitat on
affected lands, resiliency or sensitivity of the affected sage-grouse
population or group of birds, and indirect effects of development such
as functional habitat loss due to weed invasion, noise disturbance, and
other anthropogenic stressors. Functional habitat loss results from
disturbance that changes a habitat's successional state or reduces or
removes one or more habitat functions or values; presents physical
barriers that preclude use of otherwise suitable areas; or introduces
activities that prevent animals from using suitable habitat due to
behavioral avoidance.
In evaluating the impact that residential development has on the
species, we acknowledge that enrollment in the Candidate Conservation
Agreement with Assurances (CCAA) for Gunnison sage-grouse, local
regulatory mechanisms, Federal efforts such as the Gunnison Basin
Candidate Conservation Agreement (CCA), and implementation of future
conservation easements and similar conservation efforts will, upon
effective implementation, likely reduce, but not necessarily preclude,
impacts from residential development. However, as described in more
detail in Conservation Programs and Efforts Related to Habitat
Conservation in this Factor A analysis and in Local Laws and
Regulations in the Factor D analysis, currently available data and
information indicates that these conservation efforts do not fully
address this and other threats, or are too uncertain with respect to
their implementation and effectiveness for us to forecast or evaluate
how all of these efforts will individually or collectively influence
future residential development in the species' range, the resultant
habitat decline, and related impacts on Gunnison sage-grouse.
We base our analysis of residential development primarily on the
following available information: (1) Current and future human
population growth rates in and around occupied habitat as an indicator
of residential development; (2) total available private land area and
conservation easement protection (prohibited or restricted residential
development) in the context of total occupied habitat; and (3) the
current and potential loss of occupied and unoccupied habitats as a
result of residential development, and its direct and indirect effects
on Gunnison sage-grouse individuals and populations. Broadly, we
consider private lands in occupied habitat without conservation
easement as being at higher risk of residential development, relative
to those lands currently under conservation easement (see Other
Regulatory Mechanisms: Conservation Easements in the Factor D
analysis). Applying the best available information, these factors
depict the intensity and immediacy of impacts due to residential
development, and the exposure and anticipated response of Gunnison
sage-grouse to that impact.
Effects of Residential Development
Residential development is likely contributing to habitat decline
in parts of the range of Gunnison sage-grouse. It was estimated that 3
to 5 percent of all sage-grouse historical habitat in Colorado has been
negatively affected by town and urban development (Braun 1998, p. 7).
Habitat fragmentation resulting from human development patterns is
especially detrimental to Gunnison sage-grouse because of their
dependence on large areas of sagebrush (Patterson 1952, p. 48; Connelly
et al. 2004, p. 4-1; Connelly et al. 2011a, p. 72) and more contiguous
sagebrush habitats (Rogers 1964, p. 19; Wisdom et al. 2011, pp. 452-
453). Greater sage-grouse range retraction was linked to patterns of
remaining sagebrush habitat and loss due to factors including human
population growth and the peripherality of populations (Aldridge et al.
2008). Infrastructure such as roads and power lines associated with
residential development (urban and exurban) further contribute to
habitat decline and other impacts such as increased risk of predation.
Those specific effects are discussed elsewhere in this rule, but we
recognize the cumulative effects of development and related
infrastructure increase the level of impact on Gunnison sage-grouse.
Aldridge developed a landscape-scale spatial model predicting
Gunnison sage-grouse nesting probability based on nesting data from the
western portion of the Gunnison Basin (Aldridge et al. 2012, entire).
The study extrapolated the model to the entire Gunnison Basin to
predict the likelihood of Gunnison sage-grouse nesting throughout the
area (Aldridge et al. 2012, p. 403). Results of the model indicated
that Gunnison sage-grouse select nest sites in landscapes with a low
density of residential development (<1 percent in a 1.5 km [0.9 mi]
radii) (Aldridge et al. 2012, p. 400). Nest site selection by Gunnison
sage-grouse decreased near residential developments, out to
approximately 2.5 km (1.6 mi) from any given residential development
(Aldridge et al. 2012, p. 400). Since early brood-rearing habitat is
often in close proximity to nest sites (Connelly et al. 2000a, p. 971),
impacts to nesting habitat likely also affect nearby brood-rearing
habitat (however, individual females with broods may move large
distances (Connelly 1982, as cited in Connelly et al. 2000a, p. 971)).
Similar to the above findings (and those referenced in Aldridge et
al. 2008), based on spatial modeling of anthropogenic factors and nest
and brood habitat selection, Aldridge (2005, entire) found that nesting
greater-sage grouse and broods also tended to avoid urban development
areas and other human developments such as roads or cropland,
potentially due to predator avoidance behavior. As discussed elsewhere
in this rule, there are numerous other studies indicating that the
expansion of roads and other human development in occupied habitat can
negatively affect sage-grouse (see, e.g., Roads below.)
The RCP (GSRSC 2005, pp. 160-161) hypothesized that residential
density in excess of one housing unit per 1.3 km\2\ (0.5 mi\2\) could
cause declines in
[[Page 69231]]
Gunnison sage-grouse populations. However, because the analyses that
formed the basis for this hypothesis were preliminary and did not take
into account potential lags in the response of Gunnison sage-grouse to
development (Wiens and Rotenberry 1985, p. 666), the threshold at which
impacts are expected could be higher or lower (GSRSC 2005, p. F-3). The
resulting impacts are expected to occur in nearly all seasonal
habitats, including moderate to severe winter use areas, nesting and
brood-rearing areas, and leks (GSRSC 2005, p. 161).
Based on preliminary analysis of radio telemetry, a CPW researcher
reported that Gunnison sage-grouse do not totally avoid residences, and
that some farmyards and areas with low housing density are used by
individual birds (Phillips 2013, p. 8). Further information about this
study was provided during the public comment period by CPW, including
preliminary results of the distances for successful and unsuccessful
nests to the nearest road in Gunnison and Saguache Counties (CPW 2013b,
pp. 8-9). CPW has not provided us with these data, however, or a map of
the reported locations. We are also uncertain as to what percentage of
roads in the study may have been closed to protect nesting Gunnison
sage-grouse, which may influence nest survival. Further, this
preliminary analysis of CPW's telemetry data has not been peer
reviewed. While this information may suggest that individual Gunnison
sage-grouse within the Gunnison Basin vary in their response to
development, the preliminary nature of the study doesn't allow us to
draw any definite conclusions.
Residential development can cause habitat decline both by the
direct loss of occupied habitat and by indirect effects (e.g., off-site
or functional habitat loss, habitat degradation, loss of unoccupied
habitat). We consider both in the analysis that follows, though we
assess direct loss from a quantitative perspective and indirect effects
more qualitatively.
Indirect Effects of Residential Development
As stated above, we know that indirect effects of development such
as functional habitat loss due to weed invasion, noise disturbance, and
other anthropogenic stressors occur, and that these indirect effects
act cumulatively with the direct loss of occupied and unoccupied
habitats to fragment native sagebrush habitats and increase threats,
for example, through an increase in the number and types of predators
(see Factor C, Predation). The impact of residential development is
also increased by the additional disturbance footprint and the area of
species' avoidance of other associated infrastructure such as roads,
powerlines, and fences. Because we have no specific information about
the level of these impacts, we have evaluated them qualitatively, but
we focus the remainder of our analysis on the direct effects of
residential development.
Human Population Growth in the Rocky Mountains
Human population growth in the rural Rocky Mountains is driven by
the availability of natural amenities, recreational opportunities,
aesthetically desirable settings and views, and perceived remoteness
(Riebsame et al. 1996, p. 396, 402; Theobald et al. 1996, p. 408;
Gosnell and Travis 2005, pp. 192-197; Mitchell et al. 2002, p. 6;
Hansen et al. 2005, pp. 1899-1901). The increase in residential and
commercial development associated with expanding human populations is
different from historical land use patterns in the rural Rocky
Mountains (Theobald 2001, p. 548). The allocation of land for resource-
based activities such as agriculture and livestock production is
decreasing as the relative economic importance of these activities
diminishes (Theobald et al. 1996, p. 413; Sammons 1998, p. 32; Gosnell
and Travis 2005, pp. 191-192). Currently, agribusiness occupations
constitute approximately 3 percent of the total job base in Gunnison
County (Colorado Department of Local Affairs (CDOLA) 2009b, p. 4).
Recent conversion of farm and ranch lands to housing development has
been significant in Colorado (Odell and Knight 2001, p. 1144). Many
large private ranches in the Rocky Mountains, including the Gunnison
Basin, are being subdivided into both high-density subdivisions and
larger, scattered ranchettes with lots typically greater than 14 ha (35
ac), which encompass a large, isolated house (Riebsame et al. 1996, p.
399; Theobald et al. 1996, p. 408).
The resulting pattern of residential development in the rural Rocky
Mountains is less associated with existing town sites or existing
subdivisions, and is increasingly exurban in nature (Theobald et al.
1996, pp. 408, 415; Theobald 2001, p. 546). Exurban development is
described as low-density growth outside of urban and suburban areas
(Clark et al. 2009, p. 178; Theobald 2004, p. 140) with less than one
housing unit per 1 ha (2.5 ac) (Theobald 2003, p. 1627; Theobald 2004,
p. 139). Also, the pattern is one of increased residential lot size and
the diffuse scattering of residential lots in previously rural areas
with a premium placed on adjacency to federal lands and isolated open
spaces (Riebsame et al. 1996, p. 396, 398; Theobald et al. 1996, pp.
413, 417; Theobald 2001, p. 546; Brown et al. 2005, p. 1858).
Residential subdivision associated with exurban development causes
landscape fragmentation (Gosnell and Travis 2005, p. 196) primarily
through the accumulation of roads, buildings, (Theobald et al.1996, p.
410; Mitchell et al. 2002, p. 3) and other infrastructure such as power
lines (GSRSC 2005, p. 146).
Human Population Growth Across the Range of Gunnison Sage-Grouse
The GSRSC (2005, p. 146) identified current and potential issues
affecting Gunnison sage-grouse populations, based on conservation
status information, local working group plans, and similar documents.
Residential development, and associated habitat loss or degradation,
urban development, roads, utility corridors, and fences were all
identified as current or potential issues in each of the seven
populations.
Human population growth is occurring throughout much of the range
of Gunnison sage-grouse. The human population in all Colorado counties
within the range of Gunnison sage-grouse has increased by approximately
57.8 percent in the last several decades, since 1985 (Table 2). During
the same period, human population growth in Utah counties in Gunnison
sage-grouse range increased by about 24.5 percent (Table 3), less than
that of Colorado counties. Residential development in the Gunnison
sage-grouse range is expected to increase to meet the demand of growing
human populations.
[[Page 69232]]
Table 2--Human Population Growth in Colorado Counties in Gunnison Sage-Grouse Range, 1985 to 2012
[Colorado Department of Local Affairs (CDOLA) 2012, entire]
----------------------------------------------------------------------------------------------------------------
Human
Overlap with Gunnison population
County sage-grouse population 1985 Human 2012 Human growth from
\a\ population population 1985 to 2012
(%)
----------------------------------------------------------------------------------------------------------------
Gunnison............................. Gunnison Basin........... 10,390 15,475 48.9
Cerro Summit-Cimarron-
Sims Mesa
Ouray................................ Cerro Summit-Cimarron- 2,130 4,530 112.7
Sims Mesa.
San Miguel--Overlap with
unoccupied habitat only
San Miguel........................... Monticello-Dove Creek.... 3,189 7,580 137.7
San Miguel
Hinsdale............................. Gunnison Basin--Overlap 472 810 71.6
with unoccupied habitat
only.
Saguache............................. Gunnison Basin........... 4,400 6,304 43.3
Poncha Pass
Mesa................................. Pi[ntilde]on Mesa........ 88,0121 147,855 68.0
Montrose............................. Cerro Summit-Cimarron- 24,389 40,732 67.0
Sims Mesa.
San Miguel
Montezuma............................ Monticello-Dove Creek-- 19,283 25,437 31.9
Overlap with unoccupied
habitat only.
Delta................................ Crawford................. 23,466 30,436 29.7
Dolores.............................. Monticello-Dove Creek.... 1,548 1,994 28.8
Chaffee.............................. Poncha Pass.............. 12,349 18,151 47.0
-----------------------------------------------
Total............................ ......................... 189,637 299,304 57.8
----------------------------------------------------------------------------------------------------------------
\a\ Based on county overlap with occupied habitat (GSRSC 2005, pp. 54-102) unless noted otherwise.
Table 3--Human Population Growth in Utah Counties in Gunnison Sage-Grouse Range, 1985 to 2011
[Demographic and Economic Analysis (DEA) 2011, entire]
----------------------------------------------------------------------------------------------------------------
Human
Overlap with Gunnison population
County sage-grouse population 1985 Human 2011 Human growth from
\a\ population population 1985 to 2011
(%)
----------------------------------------------------------------------------------------------------------------
San Juan............................. Dove Creek-Monticello.... 12,300 14,954 21.6
Grand................................ Pi[ntilde]on Mesa-- 7,200 9,322 29.5
Overlap with unoccupied
habitat only.
-----------------------------------------------
Total............................ ......................... 19,500 24,276 24.5
----------------------------------------------------------------------------------------------------------------
\a\ Based on county overlap with occupied habitat (GSRSC 2005, pp. 54-102) unless noted otherwise.
These trends are expected to continue into the future (GSRSC 2005,
p. 150-153). The year 2050 projected human population for the entire
Gunnison River Basin (a watershed area spanning multiple counties),
which encompasses the majority of Gunnison sage-grouse occupied habitat
across all population areas, is expected to be 2.3 times (233 percent)
greater than the 2005 population, with Mesa and Montrose Counties being
the most populous in that area (Colorado Water Conservation Board
(CWCB) 2009, pp. 15, 53). Across the six satellite populations, the
human population in Colorado is forecasted to grow by about 60 percent,
with most of this growth (and total number of persons) occurring in
Mesa, Montrose, and Delta Counties (Table 4). Similar to the past,
future human population growth in Utah counties in Gunnison sage-grouse
range is expected to be low, approximately 14 percent by the year 2040,
lower than Colorado counties. In some counties, the population growth
is projected to occur mainly in urban areas. For example, in Grand
County, Utah, and Mesa County, Colorado, significant growth is expected
within the cities of Moab and Grand Junction, respectively. Also, we
recognize that in some counties, what appears to be significant growth
from the baseline may actually be minimal in terms of total persons
added to the population (for example, see Hinsdale County in Table 4).
In response to public comments regarding human population growth
figures for Gunnison County provided in our proposed listing rule (78
FR 2486, January 11, 2013), we discuss future human population growth
for Gunnison County in detail in the following section.
Table 4--Human Population Forecast in Colorado Counties in Gunnison Sage-Grouse Range, 2013 to 2040
[CDOLA 2011, entire]
----------------------------------------------------------------------------------------------------------------
Human
Overlap with Gunnison 2013 (current) 2040 human population
County sage-grouse population human population growth from
\a\ population forecast 2013 to 2040
(%)
----------------------------------------------------------------------------------------------------------------
Gunnison............................. Gunnison Basin........... 15,982 22,107 38.3
[[Page 69233]]
Cerro Summit-Cimarron-
Sims Mesa.
Ouray................................ Cerro Summit-Cimarron- 4,662 6,108 31.0
Sims Mesa.
San Miguel--Overlap with
unoccupied habitat only.
San Miguel........................... San Miguel............... 8,148 16,426 101.6
Monticello-Dove Creek....
Hinsdale............................. Gunnison Basin--Overlap 853 1,378 61.6
with unoccupied habitat
only.
Saguache............................. Gunnison Basin........... 6,478 9,133 41.0
Poncha Pass..............
Mesa................................. Pi[ntilde]on Mesa........ 150,123 226,263 50.7
Montrose............................. Cerro Summit-Cimarron- 41,751 75,048 79.8
Sims Mesa.
San Miguel...............
Montezuma............................ Monticello-Dove Creek- 26,481 42,947 62.2
Overlap with unoccupied
habitat only.
Delta................................ Crawford................. 31,741 59,142 86.3
Dolores.............................. Monticello-Dove Creek.... 2,097 3,313 57.9
Chaffee.............................. Poncha Pass.............. 18,726 30,282 61.7
-----------------------------------------------
Rangewide Total.................. ......................... 307,042 492,147 60.3
----------------------------------------------------------------------------------------------------------------
\a\ Based on county overlap with occupied habitat (GSRSC 2005, pp. 54-102) unless noted otherwise.
Table 5--Human Population Forecast in Utah Counties in Gunnison Sage-Grouse Range, 2013 to 2040
[DEA 2012, entire].
----------------------------------------------------------------------------------------------------------------
Human
Overlap with Gunnison 2040 human population
County sage-grouse population 2010 human population growth from
\a\ population forecast 2013 to 2040
(%)
----------------------------------------------------------------------------------------------------------------
San Juan............................. Dove Creek-Monticello.... 14,746 15,191 3.0
Grand................................ Pi[ntilde]on Mesa-- 9,225 12,147 31.7
Overlap with unoccupied
habitat only.
-----------------------------------------------
Rangewide Total.................. ......................... 23,971 27,338 14.0
----------------------------------------------------------------------------------------------------------------
\a\ Based on county overlap with occupied habitat (GSRSC 2005, pp. 54-102) unless noted otherwise.
In addition to past and projected human population growth, the
impact of residential development on Gunnison sage-grouse depends on
total private land area in occupied habitat available for development.
Substantial Federal land ownership of occupied habitat in the Crawford,
Gunnison Basin, Poncha Pass, and portions of the San Miguel Basin
populations helps reduce the threat of residential development in these
areas. Conversely, large portions of occupied habitat in the Dove
Creek-Monticello, Pi[ntilde]on Mesa, Cerro Summit-Cimarron-Sims Mesa,
and some portions of the San Miguel populations are in private
ownership, making those areas more vulnerable to residential
development and associated impacts (GSRSC 2005, p. 160). Within all
Gunnison sage-grouse populations, the area of private land under
conservation easement (which generally prohibits subdivision and
restricts other residential or agricultural development to defined
areas) will help ameliorate impacts from human population growth and
residential development that might otherwise occur (see Factor D
discussion, Other Regulatory Mechanisms: Conservation Easements).
Below, Table 6 synthesizes future human population growth rates in
Gunnison sage-grouse population areas, total private land area, and
conservation easement protection in occupied habitats. As noted above,
we focused our analysis on the potential for direct habitat loss in
occupied habitats, where negative impacts are more likely to occur. We
qualitatively ranked past and forecasted human population growth for
area counties in Colorado (based on Tables 2 and 4) and Utah (based on
Tables 3 and 5), considering both percent growth and total number of
persons. Below, we apply information from Table 6 to determine the
impact of residential development to individual Gunnison sage-grouse
populations and to the species rangewide.
[[Page 69234]]
Table 6--Human Population Growth Rates and Conservation Easements in Gunnison Sage-Grouse Occupied Habitat
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Human population Private land in Private land in occupied Private land in occupied
growth rates \a\ occupied habitat habitat under habitat not under Percentage of
---------------------- ---------------------- conservation easement \b\ conservation easement total occupied
Total occupied ------------------------------------------------------ habitat at
Gunnison sage-grouse population Past: Forecast: habitat Percentage of Percentage of higher risk of
1985 to 2013 to (acres) Acres % private land private land residential
2012 2040 Acres in occupied Acres in occupied development
habitat (%) habitat (%) \c\ (%)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
San Miguel Basin.............................................. M M 101,750 49,492 49 6,961 14.1 42,531 85.9 41.8
Monticello-Dove Creek......................................... L L 112,543 100,773 90 5,482 5.4 95,291 84.6 84.7
Pi[ntilde]on Mesa............................................. H H 44,678 31,313 70 15,317 48.9 15,996 51.1 35.8
Cerro Summit-Cimarron-Sims Mesa............................... H H 37,161 28,218 76 3,484 12.3 24,734 87.7 66.6
Crawford...................................................... L M 35,015 8,481 24 2,005 23.6 6,476 76.4 18.5
Poncha Pass................................................... L L 27,747 7,893 28 0 0.0 7,893 100.0 28.4
Gunnison Basin................................................ L L 592,168 178,855 30 40,769 22.8 138,086 77.2 23.3
-----------------------------------------------------------------------------------------------------------
Rangewide Total........................................... ......... ......... 951,062 405,025 43 74,018 18.3 331,007 81.7 34.8
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Based on a qualitative assessment of past and forecast human population growth for area counties in Colorado (Tables 2 and 4) and Utah (Tables 3 and 5), considering percent growth and
total number of persons: H--High; M--Moderate; L--Low.
\b\ Lohr and Gray (2013, entire).
\c\ Calculated by dividing acres of ``private land in occupied habitat not under conservation easement'' by ``total occupied habitat.''
Based on the factors presented in Table 6 above, residential
development is likely to have the greatest impact on the San Miguel and
Cerro Summit-Cimarron-Sims Mesa populations of Gunnison sage-grouse. In
the San Miguel Basin population, moderate human population growth has
occurred and is projected through the year 2040; and private land
comprises about 49 percent of total occupied habitat, of which 14
percent is under conservation easement. This means that approximately
42 percent of total occupied habitat in the San Miguel population area
is at higher risk of residential development (Table 6). The rate of
residential development in the San Miguel Basin population area
increased between 2005 and 2008 but slowed in 2009 (CDOW 2009b, p.
135). However, a 429-ha (1,057-ac) parcel north of Miramonte Reservoir
is currently being developed. The CPW reports that potential impacts to
Gunnison sage-grouse resulting from this development may be reduced by
placing a portion of the property into a conservation easement and the
relocation of a proposed major road to avoid occupied habitat (CDOW
2009b, p. 136). A downward trend in the San Miguel population over the
last decade or more (Figure 3) indicates it may not have the resilience
(see Small Population Size and Structure) to sustain substantial
habitat losses. Therefore, residential development is a current and
future threat to Gunnison sage-grouse in the San Miguel Basin
population.
Likewise, in the Cerro Summit-Cimarron-Sims Mesa area, considerable
human population growth has occurred and is forecast through the year
2040; and private land comprises about 76 percent of total occupied
habitat, of which 12 percent is under conservation easement. This means
that approximately 67 percent of total occupied habitat in the Cerro
Summit-Cimarron-Sims Mesa population area is at higher risk of
residential development (Table 6). Scattered residential development
has recently occurred along the periphery of occupied habitat in the
Cerro Summit-Cimarron-Sims Mesa population (CDOW 2009b, p. 45). Already
limited habitat (Table 6) and low population numbers (Figure 3)
indicate the Cerro Summit-Cimarron-Sims Mesa population may not have
the resilience (see Small Population Size and Structure) to sustain
substantial habitat losses. Therefore, residential development is a
current and future threat to Gunnison sage-grouse in the Cerro Summit-
Cimarron-Sims Mesa population.
Although past and future human population growth in the Poncha Pass
population is estimated to be low, and the proportion of land at higher
risk of residential development is low (about 28 percent) (see Table
6), other information indicates that residential development is
nevertheless a threat to the Poncha Pass population. Residential
subdivision continues to be concentrated in the northern part of the
Poncha Pass population area where Gunnison sage-grouse occur most, and
CPW considers this to be the highest priority threat to this population
(CDOW 2009b, p. 124). As noted earlier, where habitat is already
severely limited, or where sage-grouse populations are small, any loss
of habitat may impact those populations (GSRSC 2005, p. 161). Due to
the pattern of residential development, already limited sagebrush
habitat in the area (about 20,000 acres), and critically low population
numbers (zero birds counted in 2013; Figure 3), residential development
is a current and future threat to the Poncha Pass population of
Gunnison sage-grouse.
For the remaining four Gunnison sage-grouse populations, we find
that current residential development may impact individual birds or
areas of habitat, but is a threat of low magnitude at the population
level at the present time. In these areas, past or projected human
population growth rates are very low, indicating that residential
development will be limited (Monticello-Dove Creek); or private land
available for residential development (considering Federal land
ownership and conservation easement protection) is limited
(Pi[ntilde]on Mesa and Crawford). For these three populations, we also
believe that the threat of residential development will remain low in
the future. With respect to the Gunnison Basin population, however, as
described in more detail below, over half of the 23.3 percent of total
occupied habitat that is at higher risk of residential development (see
Table 6) is high priority habitat, because it includes seasonally
important habitat for the species. The potential loss or degradation of
even relatively smaller portions of habitat due to future residential
development is a concern, especially if important seasonal habitats are
affected, so we believe that threats related to residential development
will be higher in the future in the Gunnison
[[Page 69235]]
Basin (see Reevaluation of Residential Development in the Gunnison
Basin).
The analysis above is focused on the threat of residential
development in occupied habitats for Gunnison sage-grouse. However, it
is reasonable to assume that residential development will also occur in
important but currently unoccupied habitats. These habitats may now or
in the future provide dispersal corridors for birds between occupied
habitat, subpopulations, or populations; or provide areas for range
migration or expansion. The threat of habitat loss or degradation due
to residential development in the San Miguel and Cerro Summit-Cimarron-
Sims Mesa populations will likely reduce habitat connectivity between
satellite populations and potential connectivity between the Gunnison
Basin population and satellite populations to the west. The GSRSC
(2005, p. 167) identified habitat areas in the San Miguel population
that provide potential linkages with the Dove Creek-Monticello
population to the west, Pi[ntilde]on Mesa population to the north, and
Cerro Summit-Cimarron-Sims Mesa population to the east. Potential
linkages in the Cerro Summit-Cimarron-Sims Mesa population were also
identified that may provide connectivity with the San Miguel population
to the west, Crawford population to the northeast, and Gunnison Basin
population to the east. Genetic evidence indicates maintaining or
enhancing habitat connectivity between populations is important for
Gunnison sage-grouse survival into the future (See detailed discussion
in Factor E analysis, Small Population Size and Structure).
Reevaluation of Residential Development in the Gunnison Basin
Population Area
In our proposed rule to list Gunnison sage-grouse as endangered, we
concluded that residential development was a principal threat to the
species as a whole. That analysis was focused on the potential impacts
of residential development in the Gunnison Basin population area, since
the vast majority of occupied habitat and birds occur there. As noted
above, based on numerous public comments and new information we
received on the proposed rule, we have reevaluated the threat of
residential development to the species, both in the individual
populations and rangewide. In this section, we describe in greater
detail the basis for our conclusions regarding the effects of
residential development, both at the present time and in the
foreseeable future, on individual birds or areas of habitat in the
Gunnison Basin population area.
Current Impacts of Residential Development
Approximately 239,640 ha (592,168 ac) of occupied habitat occur in
the Gunnison Basin. Of this, approximately 161,336 ha (398,669 ac) (67
percent) are on Federal lands; 5,906 ha (14,595 ac) (2 percent) are
State land; and 72,380 ha (178,855 ac) (30 percent) are private land
(Table 1). In this rule, our evaluation of residential development in
the Gunnison Basin is based largely on human demographic information
for Gunnison County, where nearly three-quarters (approximately 71
percent) of the Gunnison Basin population of Gunnison sage-grouse
occurs (the remainder occurs in Saguache County). Based on the
available information, we expect that the rate of future residential
development in the Saguache County portion of the Gunnison Basin will
be similar to that of Gunnison County. Approximately 30 percent of
Gunnison sage-grouse occupied habitat in the Gunnison Basin occurs on
private lands.
When evaluating Gunnison County overall (including both Gunnison
sage-grouse habitat and non-habitat areas), our analysis found that the
cumulative number of human developments (including housing,
infrastructure, and improvements to existing development) increased
considerably since the early 1970s. The number of new developments
averaged approximately 70 per year from the late 1800s to 1969,
increasing to approximately 450 per year from 1970 to 2008 (USFWS
2010a, pp. 1-5). Furthermore, there has been an increasing trend toward
development away from major roadways (primary and secondary paved
roads) into areas of occupied Gunnison sage-grouse habitat that had
previously undergone very limited development (USFWS 2010b, p. 7).
Between 1889 and 1968, approximately 51 human developments were located
more than 1.6 km (1 mi) from a major road in currently occupied
Gunnison sage-grouse habitat. Between 1969 and 2008, this number
increased to approximately 476 developments (USFWS 2010b, p. 7).
However, the majority of residential development in Gunnison County
is outside of Gunnison-sage grouse occupied habitat. About 26 percent
of housing units in Gunnison County occur within Gunnison sage-grouse
occupied habitat (Gunnison County 2013a, Appendix G, p. 9). Although
significant development has occurred in the past, residential growth in
Gunnison County has been influenced heavily by development in the East
River Valley near Crested Butte, outside of occupied habitat for
Gunnison sage-grouse (Gunnison County 2013a, pp. 69-70). Furthermore,
the majority of existing development in the lower Gunnison Basin is
concentrated near the City of Gunnison, outside of occupied habitat or
in more marginalized habitat (Gunnison County 2013c, p. 5). Gunnison
County building permit data indicate that since 1980, over 70 percent
of all county building permits have been located within subdivisions
that are already served by water and sewer services (urban service
areas). If building permits for the City of Gunnison are included, over
80 percent of all new development since 1980 has occurred in urban
service areas (Gunnison County 2013a, p. 68). Urban service areas
(utilities, trash, etc.) in Gunnison County may include small areas of
Gunnison sage-grouse habitat, but are generally less suitable than more
rural areas; therefore, human development and activities in such areas
are likely to have less impact to Gunnison sage-grouse.
Available data nonetheless indicates human developments in occupied
Gunnison sage-grouse habitat in Gunnison County occur and have
increased over time. We conducted a GIS analysis of parcel ownership
data to evaluate the spatial and temporal pattern of past human
development (including infrastructure) within occupied Gunnison sage-
grouse habitat in the Gunnison Basin population area. Our analyses were
limited to the portion of occupied habitat in Gunnison County because
parcel data was available only for Gunnison County and not Saguache
County. Approximately 18 percent of the land area within the range of
Gunnison sage-grouse in Gunnison County has a residential density
greater than one housing unit per 1.3 km\2\ (0.5 mi\2\) (USFWS 2010b,
p. 8). The GSRSC (2005, pp. 160-161) hypothesized that residential
density in excess of one housing unit per 1.3 km\2\ (0.5 mi\2\) could
cause declines in Gunnison sage-grouse populations, though there are
limitations with this assumption (see discussion above). Based on this
estimate, current human residential densities in the Gunnison Basin
population area are such that they may be having an impact on Gunnison
sage-grouse in at least 18 percent of the occupied area.
In our proposed rule to list Gunnison sage-grouse as endangered, we
also applied a 1.5 km (.93 mi) ``zone of influence'' to residential
development in Gunnison County (based on Aldridge et al. 2012, p. 400),
in an effort to evaluate how the current level of
[[Page 69236]]
residential development may be impacting habitat and limiting the
Gunnison Basin population of sage-grouse (for more details, see 78 FR
2486, January 11, 2013). That analysis led us to conclude that within
occupied Gunnison sage-grouse habitat in Gunnison County, 49 percent of
the land area within the range of Gunnison sage-grouse had at least one
housing unit within a radius of 1.5 km (0.9 mi). We found that this
level of residential development strongly decreased the likelihood of
Gunnison sage-grouse using these areas as nesting habitat. Based on
this analysis, we determined that residential development, particularly
in the Gunnison Basin, was currently a principal threat to the species.
This conclusion was critical to our proposal to list the species as
endangered.
Since the listing proposal, we have received significant comments
and new information regarding this conclusion, and particularly our
application of the Aldridge et al. 2012 study, to find that human
development is currently negatively affecting the species' utilization
of 49 percent of occupied habitat in Gunnison County. As noted by
various commentators, this conclusion is at odds with the current
status of the Gunnison Basin population, which, as described above, is
and has been relatively stable for the last 19 years, based on lek
count data. If residential development was currently negatively
impacting such a significant percentage of occupied habitat in the
Gunnison Basin population, we would expect to see some evidence of this
in these population trends. This is so even recognizing that, as a
consequence of their site fidelity to seasonal habitats (Lyon and
Anderson 2003, p. 489), measurable population effects may lag behind
negative changes in habitat (Harju et al. 2010, entire; Wiens and
Rotenberry 1985, p. 666). As a result, we believe that our use of
Aldridge et. al 2012, as described above, significantly overestimated
the impact that current levels of residential development in Gunnison
County are having on the species.
Based on this reevaluation, we conclude that current development in
the Gunnison Basin population area is a threat of low magnitude to the
persistence of this Gunnison sage-grouse population. Despite past
residential development in the Gunnison Basin, the Gunnison Basin
population of Gunnison sage-grouse has remained relatively stable over
the past 19 years, based on lek count data and population estimates
(Figure 2). The Gunnison Basin population is currently large and
relatively stable and appears to be resilient (see further discussion
under Small Population Size and Structure section). Therefore, this
population has been able to sustain the negative effects of development
at current levels.
Future Impacts of Residential Development
Residential development in occupied habitat in the Gunnison Basin
will increase in the future, which means the impacts from such
development will also increase. Based on new information received since
the proposed rule, however, we believe that the rate of increase may be
less than what we determined in the proposed rule. Projections for
human population growth in Gunnison County range from about 0.75
percent to 2.15 percent annually, depending on the source (Table 7).
The current (2013) estimated human population of Gunnison County is
15,982 (CDOLA 2011, entire). By 2050, the human population in Gunnison
County is projected to be 20,877 to 37,828 people (Table 7). In our
proposed rule to list Gunnison sage-grouse as endangered (78 FR 2486,
January 11, 2013), we applied the Colorado Water Conservation Board's
(CWCB) middle-growth scenario of 1.7 percent annual growth for Gunnison
County (CWCB 2009, p. 53). We now recognize this figure may
overestimate actual growth in the area due to that study's broader
geographic focus (Colorado watersheds) and purpose (to forecast water
use and demands). The Colorado State Demographer (CDOLA 2011, entire)
estimated an average annual growth rate of 1.2 percent for Gunnison
County, with approximately 22,107 people by the year 2040, or
approximately 38 percent greater than the 2013 population.
Coincidentally, these projections are near the average of the range of
projected growth rates from the various sources (Table 7), and
represent a reliable estimate of expected future growth in the Gunnison
Basin area.
Table 7--Human Population Projections for Gunnison County
----------------------------------------------------------------------------------------------------------------
Average annual growth
Source rate Population projection Source/ citation
----------------------------------------------------------------------------------------------------------------
Colorado Water Conservation Board. 1.06%--low scenario... By the year 2050:.... CWCB 2009, p. 53.
1.70%--middle scenario 23,314--low scenario
2.15%--high scenario.. 31,086--middle
scenario.
37,828--high
scenario.
Colorado State Demographer........ 1.2%.................. By the year 2040:.... CDOLA 2011, entire.
22,107..............
Gunnison County................... 1%.................... By the year 2050:.... Gunnison County 2013a, p. 69.
20,877..............
Gunnison City Council............. 0.75%................. n/a.................. City of Gunnison 2013, p. 4.
----------------------------------------------------------------------------------------------------------------
Future population growth in the Saguache County portion of the
Gunnison Basin is projected to be 1.5 percent per year, with an
estimated population of 9,133 by the year 2040, or approximately 41
percent greater than the 2013 population (Table 4 above).
All population projections from Table 4 and Table 7 above indicate
the density and distribution of human residences in the Gunnison Basin
will increase in the future. The precise rate of human population
growth in Gunnison or Saguache Counties, however, is not the
determinative factor in assessing whether the Gunnison Basin population
of Gunnison sage-grouse will persist into the future. As discussed
below, future residential development in occupied habitat in the
Gunnison Basin is constrained by the relatively limited area of
developable private lands. In addition, if future residential
development follows past patterns, much of this future development in
Gunnison County will occur outside of Gunnison sage-grouse habitat and
within existing urban or otherwise developed areas. Nonetheless, even
under this development pattern, approximately 26 percent of future
residential development in Gunnison County would occur in occupied
[[Page 69237]]
Gunnison sage-grouse habitat (Gunnison County 2013a, Appendix G, p. 9).
Of the 239,640 ha (592,168 ac) of occupied habitat in the Gunnison
Basin, approximately 72,380 ha (178,855 ac) (30 percent) are on private
lands (Table 6). Approximately 16,499 ha (40,769 ac) (22.8 percent) of
these private lands, or 6.9 percent of occupied habitat in the Gunnison
Basin population area, are currently under conservation easement where
development is prohibited or restricted to protect conservation values,
including values for Gunnison sage-grouse on some properties (Gunnison
County 2013b, p. 21; Lohr and Gray 2013, p. 54). (Refer to Factor D
analysis, Other Regulatory Mechanisms: Conservation Easements for a
detailed discussion.) Approximately 55,881 ha (138,086ac) (77.2
percent) of private lands are not currently under conservation easement
and, thus, are at higher risk of residential development. This
constitutes 23.3 percent of the entire occupied range in the Gunnison
Basin. Therefore, about 23.3 percent of the 239,640 ha (592,168 ac) of
total occupied habitat in the Gunnison Basin is at higher risk of
residential development (relative to lands not protected under
conservation easement).
Over half of this at risk occupied habitat currently consists of
high priority habitat for the species. Based on the habitat
recommendations in the RCP, the Gunnison Basin Sage-Grouse Strategic
Committee developed a Habitat Prioritization Tool (Gunnison County
2013a, Appendix G; see detailed description under Local Laws and
Regulations, Gunnison County), which identifies sage-grouse habitat and
then discounts the value of the habitat based on distance to
structures, roads, and power lines. The Habitat Prioritization Tool
determined that, of private lands in occupied habitat in the Gunnison
Basin not under conservation easement, over half are Tier 1 habitat, or
high value habitat (e.g., lekking, nesting, brood-rearing, or wintering
habitat); the remaining habitat is classified as Tier 2, or lower value
habitat (Cochran 2013, pers. comm.) that is closer to structures,
roads, and power lines. This tool does not quantify or map unoccupied
habitats. Based on this figure, of the 55,881 ha (138,086 ac) or 23.3
percent of total occupied habitat in the Gunnison Basin at higher risk
of residential development (as discussed below), 28,033 ha (69,270 ac)
of those are Tier 1, or priority habitat.
The GSRSC (2005, p. 161) cautioned that, in the Gunnison Basin
population, any habitat loss from residential development should be
avoided or mitigated because of this population's high conservation
importance. As noted earlier, the GSRSC (2005, p.161) suggested that
the greatest impacts from permanent habitat loss are expected in
seasonal habitats most important to Gunnison sage-grouse, such as areas
used during moderate to severe winters or in lekking, nesting, or
brood-rearing habitats. These areas are quantified within the Tier 1
habitats of the Habitat Prioritization Tool described above, and
constitute approximately 69,000 acres. Forty-five percent of the leks
in the Gunnison Basin population area occur on private lands (see
discussion above in the Current Distribution and Population Estimates
and Trends section), and any impacts within 4 miles of these leks could
affect nesting and brood-rearing activities.
Additional residential development in those high value habitats
could result in increased impacts on Gunnison sage-grouse in the
Gunnison Basin. Lesser impacts would be expected in Tier 2 habitats,
and from indirect effects of development in unoccupied habitats. These
impacts, particularly to the seasonally important habitats, are a
concern, and we expect impacts, and the level of threat posed by
residential development, to increase in the future, although at a
somewhat lower rate than what we described in the proposed listing
rule.
Although exurban development will likely increase as in other parts
of the rural west, if past residential growth patterns in Gunnison
County continue, we can expect the majority of residential development
to occur outside of occupied habitat and near municipalities and
existing infrastructure. Nevertheless, under these past residential
growth patterns, we would still expect approximately 26 percent of
residential growth in the future to occur in occupied habitat.
While we recognize that current conservation efforts, including
conservation easements, enforcement of current county land use
regulations, and CCAA implementation are likely to help reduce (but not
necessarily preclude) the effects of past and future residential
development on Gunnison sage-grouse and its habitat in the Gunnison
Basin, we find that such efforts will not fully address this and other
threats (see Factor A, Conservation Programs and Efforts Related to
Habitat Conservation, and Factor D, Regulatory Mechanisms). In
addition, future residential development of private lands will likely
demand new or additional infrastructure on adjacent properties such as
Federally administered lands, which may cause additional impacts to
Gunnison sage-grouse habitat (see Cumulative Effects From Factors A
through E). Although we cannot forecast what those impacts might look
like, we anticipate that such impacts on Federal lands will be
addressed, to some degree, through Federal programs and policies such
as the Gunnison Basin CCA (see Conservation Programs and Efforts
Related to Habitat Conservation in this Factor A analysis).
In summary, the threat to Gunnison sage-grouse as a result of
current residential development is less than we previously thought as
discussed above. While individual birds may be affected, current
residential development is a threat of low magnitude to Gunnison Basin
birds at the population level. Approximately 23.3 percent of the
239,640 ha (592,168 ac) of total occupied habitat in the Gunnison Basin
is at higher risk of development (i.e., are not protected by
conservation easement) in the future, relative to lands where
development is precluded, prohibited, or restricted (under State or
Federal ownership or conservation easement). Approximately 50 percent
of these developable lands are in priority habitats, and their
potential loss or degradation in the future would be a concern for the
Gunnison Basin population. In addition, indirect and cumulative effects
of infrastructure associated with residential development will increase
the impacts of future residential development. Based on these reasons,
we find that residential development is currently a threat of low
magnitude to the Gunnison Basin population of Gunnison sage-grouse, but
that it is an increasing threat in the future.
Summary of Residential Development
Residential development is likely contributing to habitat loss and
degradation throughout the range of Gunnison sage-grouse. Habitat
fragmentation resulting from human development patterns is especially
detrimental to Gunnison sage-grouse because of their dependence on
large areas of sagebrush (Patterson 1952, p. 48; Connelly et al. 2004,
p. 4-1; Connelly et al. 2011a, p. 72) and more contiguous sagebrush
habitats (Rogers 1964, p. 19; Wisdom et al. 2011, pp. 452-453).
Infrastructure such as roads and power lines associated with
residential development (urban and exurban) likely further contribute
to habitat loss and other impacts such as increased risk of predation,
particularly in the satellite populations. Residential development, and
associated habitat loss or degradation, urban development, roads,
utility corridors, and fences have all been identified as current or
[[Page 69238]]
potential issues in each of the seven populations (GSRSC 2005, p. 146).
Increasing rural and exurban development in sagebrush habitats will
continue impacting Gunnison sage-grouse.
Human population growth is occurring throughout much of the range
of Gunnison sage-grouse. The human population in all Colorado counties
within the range of Gunnison sage-grouse has increased by approximately
57.8 percent in the last several decades, since 1985 (Table 2). During
the same period, human population growth in Utah counties in Gunnison
sage-grouse range increased by about 24.5 percent (Table 3), much less
than that of Colorado counties. Population increases are expected to
continue into the future (GSRSC 2005, p. 150-153). Across the six
satellite populations, the human population in Colorado is forecasted
to grow by about 60 percent, with most of this growth (and total number
of persons) occurring in Mesa, Montrose, and Delta Counties (Table 4).
Residential development is expected to increase to meet the demand of
these growing human populations. Projected human population growth
rates in the Gunnison Basin population are considered low relative to
other populations. However, residential development in the Gunnison
Basin, including development in occupied habitat, is expected to
continue into the future and potentially impact the species and its
habitat.
Our analysis was focused on the direct loss of occupied habitat due
to residential development, in which negative impacts on the species
are more quantifiable. Indirect effects (e.g., off-site or functional
habitat loss, loss of unoccupied habitat) of habitat decline due to
residential development are also expected, however, and are evaluated
qualitatively in the above analysis. Residential growth rates and
patterns vary widely across the range of Gunnison sage-grouse. Based on
these considerations, our framework for assessing the threat of
residential development was based primarily on human population growth
rates (current and projected), the availability of developable private
lands, the ameliorating effects of conservation efforts, and other
information (see Table 6 and discussions above). Our evaluation found
that residential development is a substantial threat to the San Miguel,
Cerro Summit-Cimarron-Sims Mesa, and Poncha Pass populations of
Gunnison sage-grouse, both now and in the future. Based on the best
available information, current residential development in the remaining
Gunnison sage-grouse populations may impact individual birds or areas
of habitat, but is currently a threat of low magnitude at the
population level. Residential development will continue into the future
in these areas and, as discussed above, such development in areas of
important seasonal habitats would be a concern in these populations.
Rangewide, approximately 34.8 percent of occupied Gunnison sage-
grouse habitat is at higher risk of residential development (Table 6),
relative to lands not under conservation easement or Federal or State
ownership. As described above, human population growth is occurring
throughout much of the range of Gunnison sage-grouse, although the rate
and pattern of residential development varies widely by sage-grouse
population. These trends are expected to continue into the future,
resulting in further residential development, associated
infrastructure, and habitat loss in parts of the species' range.
The threat of habitat loss or degradation due to residential
development in the San Miguel and Cerro Summit-Cimarron-Sims Mesa
populations will likely reduce habitat connectivity between satellite
populations and, potential connectivity between the Gunnison Basin
population and satellite populations to the west. The GSRSC (2005, p.
167) identified habitat areas in the San Miguel population that provide
potential linkages with the Dove Creek-Monticello population to the
west, Pi[ntilde]on Mesa population to the north, and Cerro Summit-
Cimarron-Sims Mesa population to the east. Potential linkages in the
Cerro Summit-Cimarron-Sims Mesa population were also identified that
may provide connectivity with the San Miguel population to the west,
Crawford population to the northeast, and Gunnison Basin population to
the east. Genetic evidence indicates maintaining or enhancing habitat
connectivity between populations is important for Gunnison sage-grouse
survival into the future (See discussion in Factor E analysis, Small
Population Size and Structure). Based on the above information, we find
residential development to be a threat to Gunnison sage-grouse
rangewide, both now and into the future.
Roads
Impacts to Gunnison sage-grouse from roads may include direct
habitat loss, direct mortality, barriers to migration corridors or
seasonal habitats, facilitation of predation and spread of invasive
vegetative species, and other indirect influences such as noise (Forman
and Alexander 1998, pp. 207-231). Greater sage-grouse mortality
resulting from collisions with vehicles does occur, but mortalities are
typically not monitored or recorded (Patterson 1952, p. 81). Therefore,
it is difficult to determine the influence of road-related mortalities
on sage-grouse populations. We have no information on the frequency or
number of mortalities of Gunnison sage-grouse due to roads or vehicles,
but because of similarities in their habitat and habitat use, we expect
effects to be similar to those observed in greater sage-grouse
(described below). Roads have been shown to fragment Gunnison sage-
grouse habitat, with road avoidance by birds presumably to limit
exposure to human activity and predation (Oyler-McCance et al. 2001, p.
330). The probability of Gunnison sage-grouse habitat occupancy
(presence based on pellet surveys or sage-grouse observation) was
positively correlated with distance from roads and habitat patch size
(Oyler-McCance et al. 1999, p. 29).
The presence of roads increases human access and resulting
disturbance effects in remote areas (Forman and Alexander 1998, p. 221;
Forman 2000, p. 35; Connelly et al. 2004, pp. 7-6 to 7-25). In
addition, roads can provide corridors for predators to move into
previously unoccupied areas. Some mammalian species known to prey on
sage-grouse, such as red fox (Vulpes vulpes), raccoons (Procyon lotor),
and striped skunks (Mephitis mephitis), have greatly increased their
distribution by dispersing along roads (Forman and Alexander 1998, p.
212; Forman 2000, p. 33; Frey and Conover 2006, pp. 1114-1115). Corvids
(Family Corvidae: Crows, ravens, magpies, etc.) also use linear
features such as primary and secondary roads as travel routes (Bui
2009, p. 31), expanding their movements into previously unused regions
(Knight and Kawashima 1993, p. 268; Connelly et al. 2004, p. 12-3).
Corvids are significant sage-grouse nest predators and were responsible
for more than 50 percent of nest predations in Nevada (Coates 2007, pp.
26-30). See Factor C below for further discussion of predation.
The expansion of road networks also contributes to exotic plant
invasions via introduced road fill, vehicle transport, and road
maintenance activities (Forman and Alexander 1998, p. 210; Forman 2000,
p. 32; Gelbard and Belnap 2003, p. 426; Knick et al. 2003, p. 619;
Connelly et al. 2004, p. 7-25). Invasive species are not limited to
roadsides, but also encroach into surrounding habitats (Forman and
Alexander 1998, p. 210; Forman 2000, p. 33; Gelbard and Belnap
[[Page 69239]]
2003, p. 427). Upgrading unpaved four-wheel-drive roads to paved roads
resulted in increased cover of invasive plant species within the
interior of adjacent plant communities (Gelbard and Belnap 2003, p.
426). This effect was associated with road construction and maintenance
activities and vehicle traffic, and not with differences in site
characteristics. The incursion of invasive and exotic plants into
native sagebrush systems can negatively affect Gunnison sage-grouse
through habitat losses and conversions (see Invasive Plants).
Gunnison sage-grouse may avoid road areas because of noise, visual
disturbance, pollutants, and predators moving along a road, which
further reduces the amount of available habitat. An unpublished study
by Western State Colorado University and CPW in the Gunnison Basin
found that anthropogenic noise was significantly higher at leks closer
to roads and human activity centers than leks farther from those
sources (Piquette et al. 2013, pp. 7-8). Leks with higher noise levels
were associated with lower Gunnison sage-grouse male counts and
attendance (Piquette et al. 2013, pp. 10-11). The landscape-scale
spatial model predicting Gunnison sage-grouse nest site selection
showed strong avoidance of areas with high road densities of roads
classed 1 through 4 (primary paved highways through primitive roads
with 2-wheel drive sedan clearance) within 6.4 km (4 mi) of nest sites
(Aldridge et al. 2012 p. 397). Nest sites also decreased with increased
proximity to primary and secondary paved highways (roads classes 1 and
2) (Aldridge et al. 2012, p. 401). Male greater sage-grouse lek
attendance was shown to decline within 3 km (1.9 mi) of a deep seam
natural gas well haul road where traffic volume exceeded one vehicle
per day (Holloran 2005, p. 40). Surface coal mining activity and
associated vehicle traffic on haul roads in the North Park of Colorado
was correlated with a 94 percent reduction in the number of displaying
greater sage-grouse males over a 5-year period on leks situated within
2 km (1.24 mi) of roads (Remington and Braun 1991). Peak male greater
sage-grouse attendance at leks experimentally treated with noise from
natural gas drilling and roads decreased 29 percent and 73 percent,
respectively, relative to paired control (no treatment) areas (Blickley
et al. 2012, p. 467). Male sage-grouse depend on acoustical signals to
attract females to leks (Gibson and Bradbury 1985, p. 82; Gratson 1993,
p. 692). If noise from roads interferes with mating displays, and
thereby female attendance, younger males will not be drawn to the lek
and eventually leks will become inactive (Amstrup and Phillips 1977, p.
26; Braun 1986, pp. 229-230).
In a study on the Pinedale Anticline in Wyoming, greater sage-
grouse hens that bred on leks within 3 km (1.9 mi) of roads associated
with oil and gas development traveled twice as far to nest as did hens
that bred on leks greater than 3 km (1.9 mi) from roads. Nest
initiation rates for hens bred on leks close to roads also were lower
(65 versus 89 percent), affecting population recruitment (33 versus 44
percent) (Lyon 2000, p. 33; Lyon and Anderson 2003, pp. 489-490). Roads
may be the primary impact of oil and gas development to sage-grouse,
due to their persistence and continued use even after drilling and
production have ceased (Lyon and Anderson 2003, p. 490). Lek
abandonment patterns suggested that daily vehicular traffic along road
networks for oil wells can impact greater sage-grouse breeding
activities (Braun et al. 2002, p. 5). Similar data are not available
for Gunnison sage-grouse, so we do not know how the species responds to
roads and traffic associated with energy development, though we expect
effects would be similar to those observed in greater sage-grouse.
One study showed that road density was not an important factor
affecting greater sage-grouse persistence or rangewide patterns in
sage-grouse extirpation (Aldridge et al. 2008, p. 992). However, the
authors did not consider the intensity of human use of roads in their
modeling efforts. They also indicated that their analyses may have been
influenced by inaccuracies in spatial road data sets, particularly for
secondary roads (Aldridge et al. 2008, p. 992). Spatial modeling of
historic range where greater and Gunnison sage-grouse have been
extirpated had a 25 percent higher density of roads than occupied range
(Wisdom et al. 2011, p. 467). Wisdom et al.'s (2011, entire) greater
and Gunnison sage-grouse rangewide analysis supports the findings of
numerous local studies showing that roads can have both direct and
indirect impacts on sage-grouse distribution and individual fitness
(reproduction and survival) (e.g., Lyon and Anderson 2003 p. 490,
Aldridge and Boyce 2007, p. 520).
Recreational activities including off-highway vehicles (OHV), all-
terrain vehicles, motorcycles, mountain bikes, and other mechanized
methods of travel have also been recognized as a potential direct and
indirect threat to Gunnison sage-grouse and their habitat (BLM 2009a,
p. 36). In Colorado, the number of annual off-highway vehicle (OHV)
registrations has increased dramatically from 12,000 in 1991 to 131,000
in 2007 (BLM 2009a, p. 37). Four wheel drive, OHV, motorcycle,
specialty vehicle, and mountain bike use is expected to increase in the
future based on increased human population in Colorado and within the
range of Gunnison sage-grouse. Numerous off-road routes and access
points to habitat used by Gunnison sage-grouse combined with increasing
capabilities for mechanized travel and increased human population
further contribute to habitat decline.
Roads in the Gunnison Basin Population Area
Currently, 1,349 km (838 mi) of roads accessible to 2-wheel-drive
passenger cars occur in occupied Gunnison sage-grouse habitat in the
Gunnison Basin on all land ownerships. Four-wheel-drive vehicle roads,
as well as motorcycle, mountain bike, horse, and hiking trails are
heavily distributed throughout the range of Gunnison sage-grouse (BLM
2009a, pp. 27, 55, 86), which further increases the overall density of
roads and their direct and indirect effects on Gunnison sage-grouse.
User-created roads and trails have increased since 2004 (BLM 2009a, p.
33), although we do not know the scope of this increase.
On BLM lands in the Gunnison Basin, approximately 2,050 km (1,274
mi) of roads are currently within 6.4 km (4 mi) of Gunnison sage-grouse
leks (BLM 2010a, p. 147). This distance is thought to be important,
because eighty-seven percent of all Gunnison sage-grouse nests were
located less than 6.4 km (4 mi) from the lek of capture (Apa 2004, p.
21). However, the BLM proposed to reduce the roads on its Gunnison
Basin lands from 2,050 km (1,274 mi) to 1,157 km (719 mi) (BLM 2010a,
p. 147), including implementation of other conservation measures from
the Gunnison Basin Candidate Conservation Agreement (CCA) (BLM 2013b,
entire) (see Conservation Programs and Efforts Related to Habitat
Conservation below). The NPS completed a Motorized Vehicle Access Plan
and Environmental Assessment for the Curecanti National Recreation Area
(NPS 2010, 78 FR 72028). As of January 2014, roads open to the public
within Gunnison sage-grouse habitat (occupied and unoccupied) were
reduced from 91.1 km (56.6 mi) to 39.6 km (24.6 mi) (Stahlnecker 2014,
pers. com) (also discussed below).
[[Page 69240]]
The U.S. Forest Service (USFS) is implementing their 2010 Travel
Management Plan to benefit Gunnison sage-grouse. Approximately 66 km
(41 mi) of road have recently been decommissioned on USFS lands in the
Gunnison Basin. An additional 40-56 km (25-35 mi) of roads were
proposed for decommissioning by the USFS in 2013. The BLM, USFS, CPW,
and Gunnison County currently close 36 roads at 47 closure points to
all motorized traffic from March 15 to May 15 to minimize impacts to
Gunnison sage-grouse during the breeding season. Six USFS closures
extend to June 15 to protect nesting Gunnison sage-grouse. These
closures limit motorized access to all known leks and adjacent habitats
on public lands in the Gunnison Basin (Gunnison County 2013a, pp. 78,
127). The USFS implements winter and spring travel closures for
motorized and mechanized activities in the Flat Top Mountain and Almont
Triangle areas, which includes a total of more than 11,000 ha (27,000
ac). While road closures may be violated in a small number of
situations, we expect these seasonal closures are having a beneficial
effect on Gunnison sage-grouse in the majority of the Gunnison Basin
area through avoidance or minimization of impacts during sensitive
periods.
Using GIS and a spatial dataset of roads in the Gunnison Basin, we
evaluated the potential effects of roads to Gunnison sage-grouse and
their habitat. To account for secondary effects from invasive weed
spread from roads (see discussion below in Invasive Plants), we applied
a 0.7-km (0.4-mi) ``zone of influence'' (Bradley and Mustard 2006, p.
1146) to all roads in the Gunnison Basin. These analyses indicate that
approximately 85 percent of occupied habitat in the Gunnison Basin has
an increased likelihood of current or future road-related invasive weed
invasion, although the extent and severity of weed invasion would vary
by road and area. It is likely that all occupied habitat in the
Gunnison Basin may be negatively affected in some way by the direct or
indirect impacts of roads (see the discussion below). In addition,
available information indicates that noise from roads and other human
activity centers such as the airport may be negatively impacting
Gunnison sage-grouse reproduction in the Gunnison Basin by reducing
male sage-grouse attendance at nearby leks (Piquette et al. 2013,
entire).
The CPW (2013b, pp. 8-9) calculated the distance from roads
(highways and county roads) for 185 separate successful and
unsuccessful sage-grouse nests in the Gunnison Basin population, based
on telemetry and nesting data collected from 2005 to 2010. Roads
included highways and county roads in Gunnison and Saguache counties.
The study did not evaluate ``primitive'' roads as the Aldridge et al.
2012 study did, making this analysis more conservative. A GIS analysis
of the distance frequencies of the 185 nests did not indicate an
avoidance of roads by sage-grouse, in contrast to the findings of other
authors cited above (see discussion above). Rather, CPW believes the
data showed a correlation between a decline in the number of nests and
increasing distance from roads. Approximately 45 percent of studied
nests were within 300 m (984 ft) of a road, and 70 percent were within
500 m (1,640 ft). Nest frequency declined around distances greater than
500 m (1,640 ft) from roads. However, road density was not described
and the distance to nests may be a reflection of road density rather
than site selection. We are also uncertain as to what percentage of
these roads may have been closed to protect nesting Gunnison sage-
grouse, which may influence nest survival. The CPW acknowledged,
moreover, that their analysis was not peer reviewed, and did not
account for factors such as age (yearling vs. adult), re-nesting
(however, only 3.2 percent of females studied re-nested), or time
(i.e., the same female observed across years) (CPW 2013b, pp. 8-9). CPW
also recognized that its report of nesting success in relation to roads
only addressed one aspect of potential threats to Gunnison sage-grouse
from roads, and did not address additional threats from roads such as
impacts on suitability of brood-rearing and seasonal habitat
components, changes in lekking behavior, noise impacts, depredation
risks and chick and adult mortality (CPW 2013b, p.9). While the CPW
study may indicate that Gunnison sage-grouse in the Gunnison Basin are
not totally avoiding roads, the best available scientific information
on the effects of roads on sage-grouse and their habitats nevertheless
indicates that roads are likely having a negative impact on Gunnison
sage-grouse in the Gunnison Basin population, though the extent and
magnitude of those impacts are unknown.
Roads in All Other Population Areas
Approximately 140 km (87 mi), 243 km (151 mi), and 217 km (135 mi)
of roads (all road classes) occur on BLM lands within the Cerro Summit-
Cimarron-Sims Mesa, Crawford, and San Miguel Basin population areas,
respectively, all of which are managed by the BLM (BLM 2009a, p. 71).
We do not have information on the total length of roads within the
Monticello-Dove Creek, Pi[ntilde]on Mesa, or Poncha Pass Gunnison sage-
grouse populations. However, several maps provided by the BLM show that
roads are widespread and common throughout these population areas (BLM
2009a, pp. 27, 55, 86).
In the Crawford population area, Montrose County seasonally closes
C77 Road from March 15 through May 15 to protect Gunnison sage-grouse
during the breeding season (Gunnison County 2013, App. 1.G.40).
Likewise, Saguache County seasonally closes three roads in the Poncha
Pass population, and one road in the Gunnison Basin population area
(Gunnison County 2013, App. 1.I.49). San Miguel County vacated,
reclaimed, and relocated a county road in the San Miguel Basin to
protect a lek in the Miramonte area (Gunnison County 2013, App.
1.K.67). San Miguel County also restricts road traffic speed year-round
to 10 miles per hour or less on another road in the Miramonte area
(Gunnison County 2013, App. 1.K.67.b). An Ouray County resolution
(Resolution Number 2013-022, entire), adopted on May 28, 2013, provides
that seasonal restrictions (March 15 until May 15) be implemented for
roads (not belonging to adjacent property owners or their guests), and
appropriate terms and conditions be applied during this same time
period at construction sites within 0.6 miles of a lek to minimize and
avoid impacts on breeding and brood-rearing habitat. This affects
portions of the San Miguel and Cerro Summit-Cimarron-Sims Mesa
populations. We expect these seasonal closures and restrictions are
benefitting Gunnison sage-grouse in important portions of these
populations through avoidance and minimization of impacts during
sensitive periods. However, we believe that roads are having negative
impacts at some level on all Gunnison sage-grouse populations.
Summary of Roads
As described above in the Residential Development section, the
human population is increasing throughout the range of Gunnison sage-
grouse (CDOLA 2009a, pp. 2-3; CWCB 2009, p. 15), and data indicates
this trend will continue. Gunnison sage-grouse are dependent on large
landscapes to meet their life history needs (GSRSC 2005, pp. 26-30) and
contiguous sagebrush habitat (Rogers 1964, p. 19; Wisdom et al. 2011,
pp. 452-453). The collective influences of fragmentation and
disturbance from roads reduce the amount of effective habitat to the
extent that they are avoided by sage-grouse (Aldridge et al.
[[Page 69241]]
2012, p. 402; Aldridge and Boyce 2007, p. 520; Knick et al. 2011, pp.
212-219 and references therein; CPW 2013, pp. 8-9). Given the current
and future human demographic and economic trends discussed above under
the Residential Development Section, we conclude that increased road
use and increased road construction associated with residential
development will continue to increase. Seasonal closures are likely
providing benefits to Gunnison sage-grouse in portions of its range and
during sensitive periods. Nevertheless, habitat decline associated with
roads, as described above, is a current and future threat to Gunnison
sage-grouse rangewide.
Powerlines
Depending on the infrastructure design, size, location, and site-
specific factors, powerlines can directly affect greater sage-grouse by
posing a collision and electrocution hazard (Braun 1998, pp. 145-146;
Connelly et al. 2000a, p. 974) and can have indirect effects by
decreasing lek recruitment (Braun et al. 2002, p. 10, Walker et al.
2007a, p. 2,644), increasing predation (Connelly et al. 2004, p. 13-
12), fragmenting habitat (Braun 1998, p. 146), and facilitating the
invasion of exotic annual plants (Knick et al. 2003, p. 612; Connelly
et al. 2004, p. 7-25). In 10 years of tracking and studying over 1,000
radio-collared sage-grouse in Colorado, CPW has documented only three
powerline strike-related mortalities (two confirmed cases, and one
suspected case) of Gunnison sage-grouse; and one powerline strike-
related mortality of greater sage-grouse (CPW 2013b, p. 11; Phillips
and Griffin 2013, pers. comm.). In contrast, powerline collisions in
southeastern Idaho accounted for 33 percent of juvenile mortality of
greater sage-grouse in low-elevation areas (Beck et al. 2006, p.
1,075). Based on spatial modeling, proximity to powerlines is
positively correlated with Gunnison and greater sage-grouse extirpation
and loss of range (Wisdom et al. 2011, pp. 467-468). Due to the
potential spread of invasive species and predators as a result of
powerline construction and maintenance, the most substantial impact of
powerlines on Gunnison sage-grouse likely comes from indirect effects,
rather than from direct mortality. The effects of powerlines to
Gunnison sage-grouse are expected to be similar to those observed in
greater sage-grouse due to similar life histories and behavior.
In areas where vegetation is low and the terrain relatively flat,
power poles provide an attractive hunting, roosting, and nesting perch
for many species of raptors and corvids, known predators of Gunnison
sage-grouse (Steenhof et al. 1993, p. 27; Connelly et al. 2000a, p.
974; Manville 2002, p. 7; Vander Haegen et al. 2002, p. 503) (see
Factor C, Predation). Power poles increase a raptor's range of vision,
allow for greater speed during attacks on prey, and serve as
territorial markers (Steenhof et al. 1993, p. 275; Manville 2002, p.
7), thereby increasing the likelihood of predation where sage-grouse
occur. Raptors may actively seek out power poles where natural perches
are limited. For example, within 1 year of construction of a 596-km
(370-mi) transmission line in southern Idaho and Oregon, raptors and
common ravens began nesting on the supporting poles (Steenhof et al.
1993, p. 275). Within 10 years of construction, 133 pairs of raptors
and ravens were nesting along this stretch (Steenhof et al. 1993, p.
275). Raven counts increased by approximately 200 percent along the
Falcon-Gondor transmission line corridor in Nevada within 5 years of
construction (Atamian et al. 2007, p. 2). Howe et al. (2014) found (1)
the average distance to a transmission line from selected raven nest
sites was approximately 2.5 times closer than from random sites, and
(2) areas comprised of nonnative vegetation next to sagebrush were more
likely to be used by ravens (p.42), suggesting that ravens selected
nest sites (1) closer to transmission lines, and (2) in close proximity
to land cover edges and areas where land cover edges adjoined one
another. A post hoc analysis revealed that ravens were most likely to
nest near edges of adjoining big sagebrush and land cover types that
were associated with direct human disturbance or fire (Howe et al., p.
43). It is reasonable to assume an increase in the abundance of corvids
within occupied Gunnison sage-grouse habitats can lead to increased
predation (see Factor C, Predation, for further discussion).
As with corvids, eagles can also increase following power line
installation. Golden eagle (Aquila chryrsaetos) predation on sage-
grouse on leks increased from 26 to 73 percent of the total predation
after completion of a transmission line within 200 meters (m) (220
yards (yd)) of an active sage-grouse lek in northeastern Utah (Ellis
1985, p. 10). The lek was eventually abandoned, and Ellis (1985, p. 10)
concluded that the presence of the powerline resulted in changes in
sage-grouse dispersal patterns and caused fragmentation of the habitat.
Golden eagles are found throughout the range of Gunnison sage-grouse
(USGS 2010, p. 1), and golden eagles were found to be the dominant
species recorded perching on power poles in Utah in Gunnison sage-
grouse habitat (Prather and Messmer 2009, p. 12). An increase in the
abundance of golden eagles associated with power lines within occupied
Gunnison sage-grouse habitats would be expected to increase predation
rates (see Factor C, Predation, for further discussion).
Greater sage-grouse leks within 0.4 km (0.25 mi) of new powerlines
constructed for coalbed methane development in the Powder River Basin
of Wyoming had significantly lower recruitment compared to leks further
from these lines, presumably resulting from increased raptor predation
(Braun et al. 2002, p. 10). Connelly et al. (2004, p. 7-26) assumed a
5- to 6.9-km (3.1- to 4.3-mi) radius buffer around the perches, based
on the average foraging distance of these corvids and raptors, and
estimated that the area potentially influenced by additional perches
provided by powerlines was 672,644 to 837,390 km\2\ (259,641 to 323,317
mi\2\), or 32 to 40 percent of their assessment area. The impact on a
given area would depend on local densities of corvids and raptors (see
discussion in Factor C, Predation).
Powerlines may negatively impact sage-grouse habitats even if
raptors are not present. The use of otherwise suitable habitat by sage-
grouse near powerlines increased as distance from the powerline
increased for up to 600 m (660 yd) (Braun 1998, p. 8), indicating sage-
grouse avoidance of powerlines. Based on those unpublished data, Braun
(1998, p. 8) reported that the presence of powerlines may limit
Gunnison and greater sage-grouse use within 1 km (0.6 mi) in otherwise
suitable habitat. Greater sage-grouse tended to avoid using brood-
rearing habitats within 4.7 km (2.9 mi) of wind energy transmission
lines in Wyoming (LeBeau 2012, p. 27).
Electromagnetic fields emitted by power and transmission lines can
alter the behavior, physiology, endocrine systems and immune function
in birds, with negative consequences on reproduction and development
(Fernie and Reynolds 2005, p. 135). Birds are diverse in their
sensitivities to electromagnetic field exposures, with domestic
chickens being very sensitive. Many raptor species are less affected
(Fernie and Reynolds 2005, p. 135). Based on spatial modeling, sage-
grouse extirpation appears to be correlated to the presence of
powerlines (Wisdom et al. 2011, p. 467). However, no studies have been
conducted specifically on the effects of electromagnetic fields on
sage-
[[Page 69242]]
grouse. Therefore, we do not know how electromagnetic fields may impact
Gunnison sage-grouse.
In addition, linear corridors through sagebrush habitats can
facilitate the spread of invasive species, such as cheatgrass (Bromus
tectorum) (Gelbard and Belnap 2003, pp. 424-426; Knick et al. 2003, p.
620; Connelly et al. 2004, p. 1-2). However, we were unable to find any
information regarding the amount of invasive species incursion
associated with powerlines within Gunnison sage-grouse habitat.
Powerlines in the Gunnison Basin Population Area
On approximately 121,000 ha (300,000 ac) of BLM land in the
Gunnison Basin, 36 rights-of-way for power facilities, power lines, and
transmission lines have resulted in the direct loss of 350 ha (858 ac)
of occupied habitat (Borthwick 2005a, pers. comm.; Borthwick 2005b,
pers. comm.). In the Curecanti National Recreation Area, Gunnison
County Electric Association has a right of way for 63 km (39 mi) of
overhead power lines, and Western Area Power Administration (WAPA) has
a 31-km (19 mi) right of way for transmission lines.
As discussed above, the impacts of these lines likely extend beyond
their actual footprint. Based on the average foraging distance of
corvids and raptors, Connelly et al. (2004, p. 7-26) assumed a 5- to
6.9-km (3.1- to 4.3-mi) radius buffer around the perches, and estimated
that the area potentially influenced by additional perches provided by
powerlines was 672,644 to 837,390 km \2\ (259,641 to 323,317 mi \2\),
or 32 to 40 percent of their assessment area. We performed a similar
GIS analysis of large transmission line location in relation to overall
habitat area and Gunnison sage-grouse lek locations in the Gunnison
Basin population area to obtain an estimate of the potential effects in
the Basin. These analyses indicate that 68 percent of the Gunnison
Basin population area is within 6.9 km (4.3 mi) of an electrical
transmission line and is potentially influenced by avian predators
using the additional perches provided by transmission lines. This area
within 6.9 km (4.3 mi) of an electrical transmission line contains 65
of 109 active leks (60 percent) in the Gunnison Basin population. While
we recognize that powerlines will not entirely preclude the use of
adjacent habitats by Gunnison sage-grouse, these results suggest that
increased predation risks associated with transmission lines could
affect a substantial portion of the Gunnison Basin population. Four
sage-grouse collisions with taller utility lines were documented during
a demographic study (Davis 2012, entire) in the Gunnison Basin, but
none of those birds were killed as a result (Phillips 2013, p. 4).
There have been no documented strike-related mortalities of Gunnison
sage-grouse in the Gunnison Basin (Phillips and Griffin 2013, pers.
comm.). Conservation measures from the Gunnison Basin CCA (BLM 2013b,
entire) are expected to reduce impacts from some future power line
projects and activities on Federal lands in the Gunnison Basin (see
Conservation Programs and Efforts Related to Habitat Conservation).
Powerlines in All Other Population Areas
A transmission line runs through the Dry Creek Basin group in the
San Miguel Basin population, and the Beaver Mesa group has two
transmission lines. None of the transmission lines in the San Miguel
Basin have raptor proofing, nor do most distribution lines (Ferguson
2005, pers. comm.), so their use by raptors and corvids as perch sites
for hunting and use for nest sites is not discouraged. In the winter of
2012, one Gunnison sage-grouse individual in the San Miguel population
died due to a powerline strike (Phillips and Griffin 2013, pers.
comm.). One major electric transmission line runs east-west in the
northern portion of the current range of the Monticello population (San
Juan County Gunnison Sage-grouse Working Group 2005, p. 17). There have
been no documented strike-related mortalities of Gunnison sage-grouse
in the Dove Creek or Pi[ntilde]on Mesa population areas (Phillips and
Griffin 2013, pers. comm.), and because of their limited extent in
occupied habitat, powerlines do not appear to be a threat to the
Pi[ntilde]on Mesa population. One transmission line parallels Highway
92 in the Crawford population and distribution lines run from there to
homes on the periphery of the current range (Ferguson 2005, pers.
comm.). Several transmission and utility lines intersect occupied
habitat in the Poncha Pass area and may be negatively impacting an
already small population and limited available habitat. A bird
translocated from the Gunnison Basin to the Poncha Pass area in 2013
was found dead under the large transmission line on the west side of
Highway 285; necropsy results indicated collision was a likely cause of
death (Phillips and Griffin 2013, pers. comm.; Nehring 2013b, pers.
comm.). During the same year, one radio collar was found under a
powerline, but no bird was observed (i.e., an unconfirmed mortality)
(Phillips and Griffin 2013, pers. comm.)
Summary of Powerlines
Human populations are projected to increase to varying degrees in
and near most Gunnison sage-grouse populations (see Residential
Development discussion above). As a result, we expect an associated
increase in distribution powerlines to meet this demand. Powerlines are
likely negatively affecting Gunnison sage-grouse as they contribute to
habitat decline and facilitation of predators of Gunnison sage-grouse.
Given the current demographic and economic trends described in the
Residential Development Section above, we conclude that existing
powerlines and anticipated distribution of powerlines associated with
residential and other development will continue to increase. Direct and
indirect impacts resulting from powerlines are a current and future
threat to Gunnison sage-grouse persistence rangewide.
Domestic Grazing and Wild Ungulate Herbivory
At least 87 percent of occupied Gunnison sage-grouse habitat on
Federal lands is currently grazed by domestic livestock (USFWS 2010c,
entire). We lack information on the proportion of Gunnison sage-grouse
habitat on private lands that is currently grazed, but it is reasonable
to expect that the proportion of grazed area is similar to that on
Federal lands because livestock grazing is the most widespread type of
land use across the sagebrush biome (Connelly et al. 2004), and almost
all sagebrush areas are managed for livestock grazing (Knick et al.
2003). Livestock grazing can have negative or positive impacts on sage-
grouse, depending on the timing and intensity of grazing and the
habitat type or attribute of interest (Crawford et al. 2004, p. 2).
Excessive grazing by domestic livestock during the late 1800s and early
1900s, along with severe drought, significantly impacted sagebrush
ecosystems (Knick et al. 2003, p. 616). Overgrazing by livestock was
cited as one of several contributing factors in the early loss and
deterioration of sagebrush range in the region (Rogers 1964, p. 13).
Historical accounts indicate that overgrazing of sagebrush range in
Colorado began around 1875. Overgrazing was apparently at its worst in
the early 1900's and continued until the BLM was organized in 1934
(Rogers 1964, p. 13). Around 1910, a gradual but marked decline in
sage-grouse numbers and distribution in Colorado had begun (Rogers
1964, pp. 20-22). Though there
[[Page 69243]]
is no evidence of direct correlation, this information suggests that
historical livestock grazing practices and overgrazing were a
contributing factor in the early loss and degradation of sagebrush
habitats and initial declines in sage-grouse numbers and distribution.
Although current livestock stocking rates in the range of Gunnison
sage-grouse are lower than historical levels (Laycock et al. 1996, p.
3), long-term effects from historical overgrazing, including changes in
plant communities and soils, persist today (Knick et al. 2003, p. 116).
In addition, widespread use of water developments in connection
with livestock grazing across the West has since increased livestock
access to sagebrush habitats, and so even reduced numbers of livestock
still pose impacts (Connelly et al. 2004, pp. 7-33, 7-35, 7-92).
However, in some cases, small scale water development may benefit the
species. For instance, in the recent past, landowners in San Juan
County, Utah, in the range of the Monticello population of Gunnison
sage-grouse did not have automatic control valves on water developments
for livestock watering. This resulted in overflow creating seasonal wet
meadow and mesic habitats often used by Gunnison sage-grouse and
broods. The recent use of more advanced watering devices and shutoff
valves has resulted in the loss of many of these created wet meadow
sites, potentially contributing to sage-grouse declines in the area
(Prather 2010, p. 27). Water developments are also a potential source
of West Nile virus, a serious risk factor to sage-grouse populations.
Unless they are designed and managed specifically to benefit Gunnison
sage-grouse, we conclude that the negative effects of water development
outweigh the positives (see Factor C discussion, Disease).
Although livestock grazing and associated land treatments have
likely altered plant composition, increased topsoil loss, and increased
spread of exotic plants, the impacts on Gunnison sage-grouse
populations are not clear. Few studies have directly addressed the
effect of livestock grazing on sage-grouse (Beck and Mitchell 2000, pp.
998-1000; Wamboldt et al. 2002, p. 7; Crawford et al. 2004, p. 11), and
little direct experimental evidence links grazing practices to Gunnison
sage-grouse population levels (Braun 1987, pp. 136-137, Connelly and
Braun 1997, p. 7-9). Rowland (2004, pp. 17-18) conducted a literature
review and found no experimental research that demonstrates grazing
alone is responsible for reduction in sage-grouse numbers.
Despite the obvious impacts of grazing on plant communities within
the range of the species, the GSRSC (2005, p. 114) could not find a
direct correlation between historical grazing and reduced Gunnison
sage-grouse numbers. Impacts from livestock grazing on individual birds
and site-specific habitat conditions may have impacts at the population
level as well, given the widespread nature of grazing. However, no
studies have documented the impacts (positive or negative) of grazing
at the population level.
Sage-grouse need significant grass and shrub cover for protection
from predators, particularly during nesting season, and females will
preferentially choose nesting sites based on these qualities (Hagen et
al. 2007, p. 46). However, specific recommendations on vegetation
characteristics and habitat requirements for sage-grouse vary. Nest
success in Gunnison sage-grouse habitat was positively correlated with
greater grass and forb heights; and shrub density and cover (Young
1994, p. 38). In contrast, nest site vegetation characteristics did not
have a strong influence on nest success between the Gunnison Basin and
San Miguel populations, where temporal factors had the greatest
influence (Davis 2012, pp. 1, 10). It is thought that, in Colorado,
sagebrush canopy cover conceals nests more than grass (GSRSC 2005, p.
73). In Oregon, grass height at greater sage-grouse nests was taller at
successful nests than at unsuccessful nests (specific grass species
that tend to be taller than others were also positively associated with
successful nests) (Gregg 1991, p. 2). Gregg et al. (1994, p. 165)
speculated that a reduction of grass heights due to livestock grazing
in sage-grouse nesting and brood-rearing areas would negatively affect
nesting success whenever cover is reduced below the 18 cm (7 in.)
needed for predator avoidance. Maintaining average grass height greater
than 18 cm (7 in.) was recommended by Connelly et al. 2000a, p. 977).
However, guideline standards from Connelly et al. (2000a, entire) are
derived primarily from research and publications from the Great Basin
and northwest, where bunch grasses predominate (GSRSC 2005, p. 73).
The RCP (GSRSC 2005, p. H-6) provided structural habitat guidelines
for Gunnison sage-grouse and recommends a grass height of 10 to 15 cm
(3.9-5.9 in.) in breeding habitats. Lupis (2005, entire) found that
despite reduced grass and forb cover, all (100 percent) Gunnison sage-
grouse nests monitored in the Monticello population were successful.
However, sample size for the study was limited to three nests, and
predator control at the time may have contributed to relatively high
nesting success (Lupis 2005, entire); inference from this study is
therefore limited. Based on measurements of cattle foraging rates on
bunchgrasses both between and under sagebrush canopies, the probability
of foraging on under-canopy bunchgrasses depends on sagebrush size and
shape. Consequently, the effects of grazing on nesting habitats might
be site-specific (France et al. 2008, pp. 392-393). Effects of grazing
on nesting habitats are dependent on the timing as well as duration and
intensity of grazing. Grazing on grasses and forbs during nesting and
early brood rearing seasons could impact food sources for young broods,
as well as alter the desired herbaceous plant community. Grazing on
grasses and forbs in late-fall or winter could reduce residual
vegetation important for hiding cover for nesting hens the following
spring. In addition, grazing on shrubs, especially sagebrush, during
winter months may cause impacts to both hiding/thermal cover as well as
the primary food resource for Gunnison sage-grouse.
Livestock grazing can also impact fire return intervals, which in
turn can affect Gunnison sage-grouse habitat quality. Fire ecology in
the sagebrush steppe ecosystem has changed dramatically with European
settlement. In high elevation sagebrush habitat, fire return intervals
have increased from 12-24 years to more than 50 years, resulting in the
dominance of woody vegetation (typically juniper and/or pi[ntilde]on
pine) and the decline of important shrubs and herbaceous understories.
At lower elevations, fire return intervals have decreased dramatically
from 50-100 years to less than 10 years due to invasion by annual
grasses resulting in the loss of native perennial shrubs, forbs, and
grasses (Crawford et al. 2004, p. 8). By changing vegetative structure
and composition, livestock grazing can contribute to either condition
(an increase in woody vegetation or invasive annual grasses) (Beck and
Mitchell 2000, pp. 995-996, and references therein), increasing the
risk of larger, more severe, or more frequent wildfires (also see
Pi[ntilde]on-Juniper Encroachment and Invasive Plants sections in this
rule). On the other hand, livestock grazing may reduce herbaceous fuel
accumulation and continuity and, consequently, the risk of wildfires in
sagebrush habitats (Davies et al. 2010, p. 662).
We know that livestock grazing influences fire ecology in sage-
grouse habitat. However, due to the spatial complexity of fire in
sagebrush ecosystems (Crawford et al. 2004, p.7),
[[Page 69244]]
and the numerous factors determining the effects of grazing on
sagebrush habitats (as described above), the effects of grazing on
sage-grouse by altering fire ecology likely vary widely across time and
space. Grazing by livestock, especially if done in a manner not
consistent with local ecological conditions, including soil types,
precipitation zones, vegetation composition and drought conditions, can
reduce the suitability of breeding and brood-rearing habitat,
negatively affecting sage-grouse populations (Braun 1987, p. 137;
Dobkin 1995, p. 18; Connelly and Braun 1997, p. 231; Beck and Mitchell
2000, pp. 998-1000; USFWS 2013e, p. 45). Livestock and wild ungulate
numbers must be managed at levels that allow native sagebrush
vegetative communities to minimally achieve Proper Functioning
Conditions for riparian areas or Rangeland Health Standards for uplands
(USFWS 2013e, p. 45). Domestic livestock grazing reduces water
infiltration rates and the cover of herbaceous plants and litter,
compacts the soil, and increases soil erosion (Braun 1998, p. 147;
Dobkin et al. 1998, p. 213). These impacts change the proportion of
shrub, grass, and forb components in the affected area, and facilitate
invasion of exotic plant species that do not provide suitable habitat
for sage-grouse (Mack and Thompson 1982, p. 761; Miller and Eddleman
2000, p. 19; Knick et al. 2011, pp. 228-232).
Cattle feed mostly on grasses, but will make seasonal use of forbs
and shrub species like sagebrush (Vallentine 1990, p. 226), the primary
source of nutrition for sage-grouse. Within the range of Gunnison sage-
grouse, sheep use of sagebrush habitats occurs primarily during the
winter and spring months, depending on elevation. Sheep feed primarily
on sagebrush and other shrubs. A sage-grouse hen's nutritional
condition affects nest initiation rate, clutch size, and subsequent
reproductive success (Barnett and Crawford 1994, p. 117; Coggins 1998,
p. 30). Grazing management practices that are inconsistent with local
ecological conditions in mesic sites result in a reduction of forbs and
grasses available to sage-grouse chicks, thereby affecting chick
survival (Aldridge and Brigham 2003, p. 30). Chick survival is one of
the most important factors in maintaining Gunnison sage-grouse
population viability (GSRSC 2005, p. 173). We conclude that livestock
utilization of forage resources has the potential to negatively impact
Gunnison sage-grouse, though the magnitude of those effects depends on
location, grazing practices, and site-specific factors.
Livestock can trample sage-grouse nests and nesting habitat.
Although the effect of trampling at a population level is unknown,
outright nest destruction has been documented, and the presence of
livestock can cause sage-grouse to abandon their nests (Rasmussen and
Griner 1938, p. 863; Patterson 1952, p. 111; Call and Maser 1985, p.
17; Holloran and Anderson 2003, p. 309; Beck and Mitchell 2000, p. 994;
Coates 2007, p. 28). Sage-grouse have been documented to abandon nests
following partial nest predation by cows (Coates 2007, p. 28). In
general, all recorded encounters between livestock and grouse nests
resulted in hens flushing from nests, which could expose the eggs to
predation. Visual predators like ravens likely use hen movements to
locate sage-grouse nests (Coates 2007, p. 33). Livestock also may
trample sagebrush seedlings, thereby removing a source of future sage-
grouse food and cover (Connelly et al. 2004, pp. 7-31, and references
therein). Trampling of soil by livestock can reduce or eliminate
biological soil crusts making these areas susceptible to cheatgrass
invasion (Mack 1981, pp. 148-149; Young and Allen 1997, p. 531).
Livestock grazing may also have positive effects on sage-grouse
under some habitat conditions. Sage-grouse use grazed meadows
significantly more during late summer than ungrazed meadows because
grazing had stimulated the regrowth of forbs (Evans 1986, p. 67).
Greater sage-grouse sought out and used openings in meadows created by
cattle grazing in northern Nevada (Klebenow 1981, p. 121). Also, both
sheep and goats have been used to control invasive weeds (Mosley 1996
in Connelly et al. 2004, pp. 7-49; Merritt et al. 2001, p. 4; Olsen and
Wallander 2001, p. 30) and woody plant encroachment (Riggs and Urness
1989, p. 358) in sage-grouse habitat. Anecdotal reports and opinion
papers (Brunner 2006, p. 16; Gunnison County 2013a, p. 95) have
suggested that cattle manure attracts and supports insect populations
upon which sage-grouse depend for survival, and that sage-grouse
``follow'' cattle through pastures. However, there is no empirical
evidence to support this theory. Further, there are no data to
substantiate the idea that in areas not actively grazed by livestock,
sage-grouse are limited in some way (Connelly et al. 2007, p. 37).
Sagebrush plant communities are not adapted to domestic grazing
disturbance. Grazing changed the functioning of systems into less
resilient, and in some cases, altered communities (Knick et al. 2011,
pp. 229-232). The ability to restore or rehabilitate areas depends on
the condition of the area relative to the ability of a site to support
a specific plant community (Knick et al. 2011, pp. 229-232). For
example, if an area has a balanced mix of shrubs and native understory
vegetation, a change in grazing management can restore the habitat to
its potential historical species composition (Pyke 2011, pp. 536-538).
Wambolt and Payne (1986, p. 318) found that resting areas from grazing
had a better perennial grass response than other treatments. Active
restoration is likely required where native understory vegetation is
much reduced (Pyke 2011, pp. 536-540). But, if an area has soil loss or
invasive species, returning the site to the native historical plant
community may be impossible (Daubenmire 1970, p. 82; Knick et al. 2011,
pp. 230-231; Pyke 2011, p. 539).
Aldridge et al. (2008, p. 990) did not find any relationship
between sage-grouse persistence and livestock densities. However, the
authors noted that livestock numbers do not necessarily correlate with
range condition. They concluded that the intensity, duration, and
distribution of livestock grazing are more influential on rangeland
condition than the density of livestock (Aldridge et al. 2008, p. 990).
Currently, little direct evidence links grazing practices to population
levels of Gunnison or greater sage-grouse. Although grazing has not
been examined at large spatial scales, as discussed above, we do know
that grazing that is incompatible with local ecological conditions and
that does not allow native sagebrush vegetative communities to
minimally achieve Proper Functioning Conditions for riparian areas or
Rangeland Health Standards for uplands can have negative impacts to
individuals, nests, breeding productivity, and sagebrush and,
consequently, to sage-grouse at local scales (USFWS 2013e, p. 44).
However, how these impacts operate at large spatial scales and thus on
population levels is currently unknown.
Livestock Grazing Allotments and Habitat Monitoring
Our analysis of grazing is focused on BLM lands because nearly all
of the information available to us regarding current grazing management
within the range of Gunnison sage-grouse was provided by the BLM.
Similar information was provided by the USFS, but was more limited
since the USFS has less occupied habitat in grazing allotments and has
a different habitat monitoring approach than BLM (see
[[Page 69245]]
discussion below). A summary of domestic livestock grazing management
on BLM and USFS lands in occupied Gunnison sage-grouse habitat is
provided in Table 8.
Table 8--Summary of Domestic Livestock Grazing Management and Allotment Data on BLM \a\ and USFS \b\ Lands in Occupied Habitat for Each of the Gunnison
Sage-Grouse (GUSG) Populations
[From BLM (2013b, p. 3-1) and USFWS (2010c), compilation of data provided by BLM and USFS]
--------------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------------
USFS BLM
-------------------------------------------------------------------------------------------------------------------
Population Number of active USFS Number of Active BLM allotments
allotments active BLM with GUSG \c\ objectives
allotments
BLM allotments assessed under LHA
\d\
Assessed BLM allotments meeting LHA
objective (standard 4)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Gunnison............................ 34..................... 62 62 100% 62 100% 20 32%
San Miguel Basin.................... no data................ 12 11 92% 10 83% \g\ 4 40%
Dove Creek.......................... n/a \e\................ 3 0 0% 3 100% \h\ Unknown ...........
Monticello.......................... n/a \e\................ 6 6 100% 5 83% 4 80%
Pi[ntilde]on Mesa................... no data................ 15 8 53% 4 27% 4 100%
Cerro Summit-Cimarron-Sims Mesa..... n/a \e\................ 6 1 17% 6 100% \i\ 1 17%
Crawford \f\........................ n/a \e\................ 8 8 100% 8 100% \j\ 7 88%
Poncha Pass......................... no data................ 8 8 100% 8 100% 8 100%
-------------------------------------------------------------------------------------------------------------------
Total........................... 34..................... 124 83 67% 101 81% 48 48%
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Bureau of Land Management.
\b\ United States Forest Service.
\c\ Gunnison sage-grouse.
\d\ Land Health Assessments.
\e\ No United States Forest land in occupied habitat in this population area.
\f\ Includes allotments on National Park Service lands but managed by the Bureau of Land Management.
\g\ BLM did not evaluate land health specific to GUSG Habitat Objectives in 8 of the 12 active allotments in the San Miguel Basin population area.
\h\ BLM did not evaluate land health specific to GUSG Habitat Objectives in any of the 3 active allotments in the Dove Creek population area.
\i\ BLM did not evaluate land health specific to GUSG Habitat Objectives in 5 of the 6 active allotments in the Cerro Summit-Cimarron-Sims Mesa
population area; however, general land health standards were met on BLM lands in this area.
\j\ BLM found that 6 allotments (75 percent) were ``meeting with problems'' for GUSG Habitat Objectives. Generally these allotments were found to be low
for some aspect of vegetation characteristics for breeding habitat recommended in GSRSC (2005 H-6).
Some of the available information on domestic livestock grazing and
its relationship to habitat conditions on Federal lands is in the form
of BLM's Land Health Assessment (LHA) data. The purpose of LHAs is to
determine the status of resource conditions within a specified
geographic area at a specific time. The LHA process incorporates land
health standards that define minimum resource conditions that must be
achieved and maintained. Further discussion on the LHA process is
provided in the following section.
The USFS does not apply the LHA process, but monitors allotment
trends through a combination of procedures including seasonal
inspections, permanent photo points, and inventory and mapping of plant
community conditions and changes over time (USFS 2010). The majority of
Gunnison sage-grouse occupied habitat in USFS grazing allotments is
located in the Gunnison Basin population area (Table 8 of Factor A
(Livestock Grazing Allotments and Habitat Monitoring)), and grazing
information from USFS as it relates to Gunnison sage-grouse is
therefore limited to this area (USFWS 2010c, p2).
Although grazing also occurs on lands owned or managed by other
entities, we have more limited information on the extent of grazing,
management, and habitat conditions in those areas. However, substantial
portions of sage-grouse habitat on private land in the Gunnison Basin,
Crawford, San Miguel, and Pi[ntilde]on Mesa population areas are
enrolled in the CCAA (see Conservation Programs and Efforts Related to
Habitat Conservation below in this Factor A section). Based on the RCP
conservation objective of securing and maintaining 90 percent of
seasonally important habitat (severe winter, nesting, and late brood-
rearing habitats) for the Gunnison sage-grouse in each population area
(GSRSC 2005, pp. 223-224), the CCAA identifies targets for private land
protection for each population area, including private lands not
already considered as protected under a conservation easement (USFWS
2006, pp. 11-12). Roughly 91 percent of the Gunnison Basin population
area target, 95 percent of the Crawford population area target, 46
percent of the San Miguel population area target, and 217 percent of
the Pi[ntilde]on Mesa population area target on private lands are
enrolled in the CCAA (Table 10). Except for properties recently
enrolled in the program, all enrolled private lands have been monitored
by CPW using standardized vegetation transects and rangeland health
assessments and, despite recent drought conditions and ongoing land
uses, no significant deviations from baseline habitat conditions were
observed (CPW 2014a, p. 1). All enrolled properties continue to be in
compliance with the terms of their Certificate of Inclusion (CI) (CPW
2014a, p. 1). This information suggests that the current level of
livestock grazing and operations on those lands is compatible with
Gunnison sage-grouse habitat needs.
Although Federal land and livestock grazing may be more regulated
than private lands grazing, we cannot make any generalizations about
how habitat conditions in those areas might compare with private lands
where livestock grazing occurs. Grazing allotments containing both
Federal and private lands are, in some cases, managed to meet land
health standards through coordination and cooperation with grazing
permittees (BLM 2013c, p. 1-2). Furthermore, many livestock operations
within the range of Gunnison sage-grouse are employing innovative
grazing strategies and conservation actions (BLM 2012a, pp. 1-2;
Gunnison County Stockgrowers 2009, entire) in
[[Page 69246]]
collaboration with the BLM and Forest Service.
BLM Land Health Assessment Standards
LHA standards are based on the recognized characteristics of
healthy ecosystems and include considerations of upland soils, riparian
systems, plant and animal communities, habitat conditions and
populations of special status species, and water quality (BLM 1997, pp.
6-7). Each LHA standard, such as the condition and health of soils,
riparian areas, or plant communities, has varying degrees of
applicability to basic Gunnison sage-grouse habitat needs. The LHA
standard most applicable to Gunnison sage-grouse is LHA Standard 4,
which is specific to special status species (BLM 1997, p. 7). Special
status species include Federally threatened, endangered, proposed, and
candidate species; recently delisted (5 years or less) species; and BLM
sensitive species. BLM sensitive species are those that require special
management consideration to promote their conservation and reduce the
likelihood and need for future listing under the Act; they are
designated by the BLM State Director(s) (BLM 2008). Gunnison sage-
grouse was designated as a BLM sensitive species in 2000, when it was
recognized as a separate species from greater sage-grouse (BLM 2009a,
p. 7). Therefore, Gunnison sage-grouse is managed by the BLM as a
special status species.
In addition to requiring stable and increasing populations and
suitable habitat for special status species, the specific indicators
for LHA Standard 4 include the presence of: minimal noxious weeds,
sustainably reproducing native plant and animal communities, mixed age
classes sufficient to sustain recruitment and mortality fluctuations,
habitat connectivity, photosynthetic activity throughout the growing
season, diverse and resilient plant and animal communities in balance
with habitat potential, plant litter accumulation, and several plant
communities in a variety of successional stages and patterns (BLM 1997,
p. 7). BLM deems an allotment that meets LHA Standard 4 to meet or
exceed a minimum resource condition for those species considered for
that area.
If livestock grazing is found to be a causal factor for not meeting
LHA standards, including LHA Standard 4, BLM implements changes to
grazing management to address those issues and to move toward achieving
desired resource conditions. Examples of adjustments include reduction
of stocking rates or utilization, changes in seasons of use, reductions
in duration of use, implementation of resting or deferred rotation
grazing systems, or change in livestock class. Under BLM Instruction
Memoranda WO-IM-2010-071, CO-IM-2010-028 and CO-IM-2013-033 (see
further discussion in Factor D on Instruction Memoranda), BLM must
consider Gunnison sage-grouse habitat needs and objectives when
analyzing grazing management and permit renewals (BLM 2013a, Attachment
1-10).
We recognize that LHAs are largely qualitative and other factors
such as impacts from invasive species, drought, OHV use, or the
lingering effects of historical overgrazing, may influence the outcome
of LHA determinations. Furthermore, BLM's application of LHA standards,
methodologies used, and data interpretation varies widely by Field
Office and State (Veblen et al. 2011, p. 3; BLM 2013c, p. 1-3), and the
potentially subjective nature of the methodology is evident in the
information on each populations presented below. Therefore, the
relationship between LHA determinations and the effects of domestic
livestock grazing on Gunnison sage-grouse is very imprecise. We also
recognize that if an allotment does not fully meet LHA Standard 4, it
does not mean the habitat is degraded or unsuitable for Gunnison sage-
grouse; and a ``not meeting'' ranking is not always attributable to
livestock grazing (BLM 2013c, p. 1-2). For instance, some vacant
allotments (not grazed by livestock) are not currently meeting LHA
Standard 4 (BLM 2013c, p. 1-3), meaning current grazing practices are
not a causal factor for that ranking. A ``not meeting'' determination
could also be based primarily on the declining status of a special
status species' population, including species other than Gunnison sage-
grouse. Finally, LHAs are typically only conducted every 10 years,
triggered by changes in management such as grazing permit renewal and
similar actions and, therefore, do not directly indicate rangeland
trend (BLM 2013c, p. 1-3). However, the fact that some grazing
allotments or areas within grazing allotments are not meeting LHA
objectives indicates that habitat conditions may be degraded for
Gunnison sage-grouse in parts of its range, and that domestic livestock
grazing may be contributing to these conditions in some instances. A
more thorough examination of each allotment not meeting LHA Standard 4
would be required to determine to what extent livestock grazing is a
causal factor.
Livestock Grazing in the Gunnison Basin Population Area
The BLM manages approximately 51 percent of the area currently
occupied by Gunnison sage-grouse in the Gunnison Basin. Nearly all (98
percent) of this area is actively grazed USFWS 2010c, p. 1). The USFS
manages livestock grazing on approximately 14 percent of the occupied
portion of the Gunnison Basin population area. Therefore, this
information on livestock grazing is pertinent to approximately 65
percent of occupied habitat in the Gunnison Basin.
In 2013, of 62 active BLM grazing allotments in the Gunnison Basin
population, all had incorporated Gunnison sage-grouse habitat
objectives as described above and completed LHAs. LHA Standard 4 was
met in 32 percent of these allotments in 2013 (Table 8 of Factor A
(Livestock Grazing Allotments and Habitat Monitoring); BLM 2013c, p. 3-
1). In 2012, on actively grazed BLM lands in the Gunnison Basin,
approximately 8 percent was ``meeting'', 17 percent was ``moving
towards'', and 63 percent was ``not meeting'' Standard 4; while 11
percent was of ``unknown'' status (BLM 2012a, pp. 2-3).
Although 2013 data shows that 68 percent of allotments may not be
meeting LHA Standard 4, the data show that 32 percent of allotments
were meeting this standard, which is an improvement over the 8 percent
indicated by the 2012 data. Nonetheless, recognizing the limitations of
LHA methodology and data as discussed above, the information above
suggests that there may be reduced habitat conditions on BLM land in
the Gunnison Basin. The cause of these conditions may or may not be
directly related to grazing management practices that were inconsistent
with local ecological conditions, either in the past or at present, but
the overall trend is for improving conditions with respect to LHA
Standard 4. The BLM has also implemented a CCA for Gunnison Basin (BLM
2013b, entire), which has specific measures for livestock grazing
within all occupied habitat in the Gunnison Basin to help improve
Gunnison sage-grouse habitat quality (BLM 2013b, Attachment 5-4) (see
Conservation Programs and Efforts Related to Habitat Conservation later
in this Factor A analysis).
In 2007 and 2008, the BLM Gunnison Field Office conducted Gunnison
sage-grouse habitat assessments in two major occupied habitat locations
in the Gunnison Basin population, quantifying
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vegetation structural characteristics and plant species diversity. Data
were collected and compared to Gunnison sage-grouse Structural Habitat
Guidelines in the 2005 Rangewide Conservation Plan (RCP) (GSRSC, 2005,
Appendix H) during optimal growing conditions in these two major
occupied areas. Of 97 transects, guidelines were met in 45 percent for
sagebrush cover; 30 percent for grass cover; 25 percent for forb cover;
75 percent for sagebrush height; 81 percent for grass height; and 39
percent for forb height (BLM 2009a, pp. 31-32). This information
suggests that habitat conditions in those areas generally fell short of
standards for Gunnison sage-grouse, particularly in relation to grass
cover, forb cover, and forb height. However, it is not known whether
those conditions were attributable to livestock grazing or other
factors such as big game forage use or weather patterns.
Livestock grazing has also negatively impacted several Gunnison
sage-grouse treatments (projects aimed at improving habitat condition)
in the Gunnison Basin (BLM 2009a, p. 34). Although these areas are
generally rested from domestic livestock grazing for 2 years after
treatment, several have been heavily used by cattle shortly after the
treatment and the effectiveness of the treatments decreased (BLM 2009a,
p. 34), which reduced the potential benefits of the treatments.
As noted earlier, the USFS does not use the LHA process, but
monitors allotment trends through a combination of procedures including
seasonal inspections, permanent photo points, and inventory and mapping
of plant community conditions and changes over time (USFS 2010,
entire). Three (9 percent) of the 34 USFS allotments in Gunnison sage-
grouse occupied habitat in the Gunnison Basin population area have
incorporated habitat objectives in their grazing plans. However, we
have no specific data that evaluate allotment conditions as they relate
to these objectives. Overall, the USFS reports that its grazing
allotments in the Gunnison Basin population area appear to be improving
in forb and grass cover but are declining in sagebrush cover (USFS
2010, entire).
All of this information indicates that grazing management may be a
factor in degraded habitat conditions for Gunnison sage-grouse in parts
of the Gunnison Basin. Given that there are far more acres of occupied
Gunnison sage-grouse habitat in the Gunnison Basin that are actively
grazed than in other populations, and over 50 percent of land (295,000
ac) in the Gunnison Basin is under BLM management, most of which is
actively grazed, overall exposure to Federal grazing management is
higher in the Gunnison Basin than elsewhere. This raises concerns about
the long-term habitat impacts of grazing management on BLM land, and
supports the need for BLM to continue to monitor and improve LHA trends
and grazing allotment management.
BLM reviews and renews grazing permits at 10 year intervals. Since
at least 2010 BLM has modified grazing permit terms and conditions in
areas determined to be ``not meeting'' LHA standards through the permit
renewal process. Examples of new permit terms or conditions required by
the BLM include implementation of rotational grazing systems, deferment
or elimination of grazing in certain pastures, reduced grazing
duration, changes in season of use, reduced stocking rates, fencing
livestock out of riparian areas, or incorporating specific habitat
objectives for Gunnison sage-grouse or other special status species
(BLM 2012a, pp. 1-2). It is anticipated that these changes will
minimize further impacts to habitat and, if continued in the future
through Instruction Memoranda or Resource Management Plan Amendments
(see Factor D discussion), improve degraded habitats for Gunnison sage-
grouse in the Gunnison Basin. Likewise, conservation measures from the
CCA (BLM 2013b, entire) should continue to reduce impacts from
livestock grazing and operations on Federal lands in the Gunnison Basin
(see Conservation Programs and Efforts Related to Habitat Conservation
later in this Factor A analysis for more details).
Some data indicate habitat conditions within a part of occupied
habitat in the Gunnison Basin may be favorable to Gunnison sage-grouse
(Williams and Hild 2011, entire). Detailed vegetation monitoring was
conducted on six study sites, across the Gunnison Basin during 2010 and
2011 in order to determine baseline habitat conditions for a potential
future study of the effects of manipulating livestock grazing on
Gunnison sage-grouse habitat (Williams and Hild 2011, entire).
Transects were conducted on private, BLM, USFS, and CPW land. Despite
lower than average precipitation in 2010, and wide variability of
habitat conditions across the study area, most vegetation measurements
were within the structural habitat guidelines for Gunnison sage-grouse
from the 2005 Rangewide Conservation Plan (GSRSC \b\ 2005, pp. H-6-H-
8). However, measuring livestock grazing effects was not an objective
of the study (Phillips 2013, p. 4). The extent of past or current
livestock grazing in these areas was not described, nor did the study
compare un-grazed to grazed areas. Further, transect locations were
prioritized and selected in important breeding areas used by radio-
collared Gunnison sage-grouse, potentially biasing study results.
Therefore, the relationship between livestock grazing and habitat
conditions is unknown under this study, and there is limited ability to
infer conditions in other portions of the Gunnison Basin not
prioritized for sampling.
Livestock Grazing in All Other Population Areas
The BLM manages approximately 36 percent of the area currently
occupied by Gunnison sage-grouse in the San Miguel Basin, and
approximately 79 percent of this area is actively grazed. Grazing also
occurs on lands owned or managed by other entities within the San
Miguel Basin, but we have no information on the extent of grazing in
these areas. Within the occupied range in the San Miguel population, no
active BLM grazing allotments have Gunnison sage-grouse habitat
objectives incorporated into the allotment management plans or Records
of Decision for permit renewals (USFWS 2010c, p. 9). In 2013, 10 (83
percent) of 12 active allotments in the San Miguel population area had
LHAs completed in the last 15 years; however, BLM only evaluated land
health specific to Gunnison sage-grouse habitat objectives in four (33
percent) of these 12 allotments. Of the four allotments evaluated, all
were found to be meeting LHA Standard 4. LHA data are not available for
conditions in the remaining 8 allotments where Gunnison sage-grouse
habitat objectives were not considered (Table 8 of Factor A (Livestock
Grazing Allotments and Habitat Monitoring); BLM 2013c, p. 3-1).
Therefore, for the four allotments in the San Miguel population area
for which we have information, it appears that grazing is managed in a
manner consistent with land health standards and habitat requirements
for Gunnison sage-grouse.
More than 81 percent of the area occupied by the Dove Creek group
is privately owned. The BLM manages 11 percent of the occupied habitat,
and 41 percent of this area is actively grazed. Within the occupied
range in the Dove Creek group of the Monticello-Dove Creek population,
there are three active BLM grazing allotments, and none of these have
Gunnison sage-grouse habitat objectives incorporated into the allotment
management plans or Records of Decision for permit renewals (Table 8 of
Factor A (Livestock Grazing
[[Page 69248]]
Allotments and Habitat Monitoring); USFWS 2010c, p. 3; BLM 2013c, p. 3-
1). In 2013, all three active allotments in occupied habitat had
completed LHAs. However, because Gunnison sage-grouse habitat
objectives were not considered in these assessments, habitat conditions
for Gunnison sage-grouse are unknown (BLM 2013c, p. 3-1). Gunnison
sage-grouse are not specifically considered in grazing management plans
or permits in this area. Due to the lack of data specific to Gunnison
sage-grouse, it is unknown how livestock grazing may be influencing the
species or its habitat in the Dove Creek population area.
More than 95 percent of the area occupied by the Monticello
population is privately owned. The BLM manages 4 percent of the
occupied habitat, and 83 percent of this area is grazed. Within the
occupied range in the Monticello population, all 6 active BLM grazing
allotments have Gunnison sage-grouse habitat objectives incorporated
into the allotment management plans or Records of Decision for permit
renewals (USFWS 2010c, p. 6). In 2009 (the most recent information
received from BLM on this topic), 88 percent of the area of occupied
habitat in active allotments had a recently completed LHA.
Approximately 60 percent of the area in occupied habitat in active
allotments was found by the BLM to meet LHA Standard 4. Given the small
amount of land managed by the BLM in this area, most of which is
meeting Standard 4, this information suggests that grazing on the
majority of the small percentage of lands managed by the BLM in the
Monticello population area is likely managed in a manner consistent
with land health standards and habitat requirements for Gunnison sage-
grouse.
The majority of occupied habitat in the Monticello population is in
private ownership and is actively grazed by cattle. Sheep historically
grazed this area as well (Messmer 2013, p. 16). A significant portion
of the agricultural lands in Monticello population are enrolled in the
Conservation Reserve Program (CRP), and much of these lands are used by
Gunnison sage-grouse (Lupis et al. 2006, pp. 959-960; Ward 2007, p.
15). CRP land has provided a considerable amount of brood-rearing
habitat in the Monticello group because of its forb component. Grazing
of CRP land in Utah occurred in 2002 under emergency Farm Bill
provisions due to drought and removed at least some of the grass and
forb habitat component, thus likely negatively affecting Gunnison sage-
grouse chick survival (see NRCS and Private Land Conservation Efforts).
Radio-collared males and non-brood-rearing females exhibited temporary
avoidance of grazed fields during and after grazing (Lupis et al. 2006,
pp. 959-960), although one hen with a brood continued to use a grazed
CRP field and successfully fledged her brood.
The BLM manages 28 percent of occupied habitat in the Pi[ntilde]on
Mesa population area, and approximately 97 percent of this area is
grazed. Over 50 percent of occupied habitat in this population area is
privately owned, and while grazing certainly occurs on these lands, we
have no information on its extent. Within the occupied range in the
Pi[ntilde]on Mesa population, 8 of 15 (53 percent) active BLM grazing
allotments have Gunnison sage-grouse habitat objectives incorporated
into the allotment management plans or Records of Decision for permit
renewals (USFWS 2010c, p. 5). In 2013, four of these allotments (27
percent) had completed LHAs. Of the four allotments in which LHAs were
completed, all (100 percent) were found to be meeting LHA Standard 4
(Table 8 of Factor A (Livestock Grazing Allotments and Habitat
Monitoring); BLM 2013c, p. 3-1). Therefore, for the small portion of
the Pi[ntilde]on Mesa population area for which we have information, it
appears that grazing is managed in a manner consistent with Gunnison
sage-grouse habitat requirements.
Over 76 percent of the area occupied by the Cerro Summit-Cimarron-
Sims Mesa population is privately owned. The BLM manages only 13
percent of the occupied habitat, of which 83 percent is grazed. Within
the occupied range in the Cerro Summit-Cimarron-Sims Mesa population, 1
of 6 active BLM grazing allotments have Gunnison sage-grouse habitat
objectives incorporated into the allotment management plans or Records
of Decision for permit renewals (USFWS 2010c, p. 7). In 2013, of six
active allotments, all had completed LHAs; however, BLM only evaluated
land health specific to Gunnison sage-grouse habitat objectives in one
(17 percent) of these six allotments. That single allotment was found
to be meeting LHA Standard 4. However, general land health standards
(not specific to Gunnison sage-grouse) were met on BLM lands in this
area, although such conditions may or may not meet the needs of
Gunnison sage-grouse. LHA data specific to Gunnison sage-grouse habitat
objectives are not available for the remaining five allotments (Table 8
of Factor A (Livestock Grazing Allotments and Habitat Monitoring); BLM
2013c, p. 3-1). However, for the small portion of the Cerro Summit-
Cimarron-Sims Mesa population area for which we have information, it
appears that grazing is being managed in a manner consistent with land
health standards and habitat requirements for Gunnison sage-grouse.
Lands administered by the BLM and NPS comprise over 75 percent of
occupied habitat in the Crawford population, and 96 percent of this
area is actively grazed. Grazing allotments on NPS lands in this area
are administered by the BLM. In 2013, of eight active allotments in the
Crawford population, all had incorporated Gunnison sage-grouse habitat
objectives and completed LHAs. Seven (88 percent) of these eight
allotments were found to be meeting LHA Standard 4, however 6 of those
allotments were defined as ``meeting with problems'' (generally these
allotments were found to be low for some aspect of vegetation
characteristics for breeding habitat recommended in GSRSC) (Table 8 of
Factor A (Livestock Grazing Allotments and Habitat Monitoring); BLM
2013c, p. 3-1). Based on this information, it appears that grazing may
be managed in a manner consistent with Gunnison sage-grouse
conservation in the majority of the Crawford population area.
The BLM manages nearly half of occupied habitat in the Poncha Pass
population area, and approximately 98 percent of this area is actively
grazed. Within the occupied range in the Poncha Pass population, all
eight active BLM grazing allotments have Gunnison sage-grouse habitat
objectives incorporated into the allotment management plans or Records
of Decision for permit renewals (USFWS 2010c, p. 4). In 2013, all
active allotments in occupied habitat had completed LHAs, and all were
meeting LHA objectives. Based on this information it appears that
grazing is managed in a manner consistent with Gunnison sage-grouse
conservation on BLM land in the Poncha Pass population area.
Wild Ungulate Herbivory in All Population Areas
Overgrazing by deer and elk may cause local degradation of habitats
by removal of forage and residual hiding and nesting cover. Hobbs et
al. (1996, pp. 210-213) documented a decline in available perennial
grasses as elk densities increased. Such grazing could negatively
impact nesting cover for sage-grouse. The winter range of deer and elk
overlaps the year-round range of the Gunnison sage-grouse. Excessive
but localized deer and elk grazing has been documented in the Gunnison
Basin (BLM 2005a, pp. 17-18; Jones 2005, pers. comm.).
[[Page 69249]]
Grazing by deer and elk occurs in all Gunnison sage-grouse
population areas. Although we have no information indicating that
competition for resources is limiting Gunnison sage-grouse in the
Gunnison Basin, BLM observed that certain mountain shrubs were being
browsed heavily by wild ungulates (BLM 2009a, p. 34). Subsequent
results of monitoring in mountain shrub communities indicated that
drought and big game were having large impacts on the survivability and
size of mountain mahogany (Cercocarpus utahensis), bitterbrush (Purshia
tridentata), and serviceberry (Amelanchier alnifolia) in the Gunnison
Basin (Japuntich et al. 2010, pp. 7-9). The authors speculated that
observed reductions in shrub size and vigor will reduce drifting snow
accumulation resulting in decreased moisture availability to grasses
and forbs during the spring melt. Reduced grass and forb growth could
negatively impact Gunnison sage-grouse nesting and early brood-rearing
habitat. It is also thought that elk numbers and their seasonal
occurrence in the Crawford population may be contributing to habitat
impacts and direct disturbance of Gunnison sage-grouse (BLM 2013c, p.
4-9).
Summary of Domestic Grazing and Wild Ungulate Herbivory
Livestock management and domestic grazing have the potential to
degrade Gunnison sage-grouse habitat. Grazing incompatible with local
ecological conditions, as described above, can adversely impact nesting
and brood-rearing habitat by decreasing vegetation available for
concealment from predators. Grazing incompatible with local ecological
conditions also has been shown to compact soils, decrease herbaceous
abundance, increase erosion, and increase the probability of invasion
of exotic plant species (GSRSC 2005, p. 173).
The impacts of livestock operations on Gunnison sage-grouse depend
upon stocking levels and season of use. We recognize that not all
livestock grazing results in habitat degradation, and many livestock
operations within the range of Gunnison sage-grouse are employing
innovative grazing strategies and conservation actions (BLM 2012a, pp.
1-2; Gunnison County Stockgrowers 2009, entire) in collaboration with
the BLM and Forest Service. As discussed above, habitat conditions are
likely favorable to Gunnison sage-grouse in part of the Gunnison Basin
(Williams and Hild 2011, entire), although the relationship of
livestock grazing to habitat conditions in those areas is unknown.
As described above, the relationship between LHA determinations and
the effects of domestic livestock grazing on Gunnison sage-grouse is
imprecise, and the application of LHA methods varies widely across the
species' range. The best available information suggests that LHA
objectives important to Gunnison sage-grouse are not being met across
parts of the species' range and that livestock grazing is likely
contributing to those conditions in some instances. Reduced habitat
quality in those areas, as reflected in LHA data, is likely negatively
impacting Gunnison sage-grouse in some of the populations, including
the Gunnison Basin. In summary, for BLM allotments, 67 percent have
Gunnison sage-grouse habitat objectives, and 39 percent are meeting LHA
Standard 4 (Table 8 of Factor A (Livestock Grazing Allotments and
Habitat Monitoring)).
Numerous public comments on our proposed rule to list Gunnison
sage-grouse as endangered (78 FR 2486, January 11, 2013) suggested that
because the Gunnison Basin population is large and stable (but see
additional discussion regarding this assumption in Factor E (Small
Population Size and Structure)), current livestock grazing practices
are not having adverse effects on this population. While we agree that,
relative to the satellite populations, the Gunnison Basin population is
large and lek count data indicate it is currently stable, there are no
data to demonstrate whether livestock grazing is limiting the
population. The best available data suggests that livestock grazing
that is done in a manner inconsistent with local ecological conditions
is likely negatively impacting localized areas of habitat and
individual birds in the Gunnison Basin and in other populations.
We know that grazing incompatible with local ecological conditions
can have negative impacts to sagebrush and consequently to Gunnison
sage-grouse at local scales. Impacts to sagebrush plant communities as
a result of grazing are occurring on a large portion of the range of
the species. As described in more detail below, conservation measures
from the Gunnison Basin CCA (BLM 2013b, entire) should continue to
reduce impacts from livestock grazing and operations on Federal lands
in the Gunnison Basin. Likewise, conservation measures from the CCAA
Program have minimized impacts from livestock grazing and operations on
private lands across the range of Gunnison sage-grouse (see
Conservation Programs and Efforts Related to Habitat Conservation later
in this Factor A discussion). We expect livestock grazing to continue
throughout the range of Gunnison sage-grouse for as long as it is
economically viable. Since the winter range of deer and elk overlaps
the year-round range of Gunnison sage-grouse and there is documentation
of isolated localized excessive grazing by deer and elk as discussed
above, effects of domestic livestock grazing are likely intensified by
browsing of woody species by wild ungulates in portions of the Gunnison
Basin and the Crawford area, and potentially other populations. Habitat
degradation that can result from grazing in a manner incompatible with
local ecological conditions, particularly with the interacting factors
of invasive weed expansion and climate change, is a current and future
threat to Gunnison sage-grouse persistence.
Fences
Effects of fencing on sage-grouse include direct mortality through
collisions, creation of raptor and corvid perch sites, the potential
creation of predator corridors along fences (particularly if a road is
maintained next to the fence), incursion of exotic species along the
fencing corridor, and habitat decline (Call and Maser 1985, p. 22;
Braun 1998, p. 145; Connelly et al. 2000a, p. 974; Beck et al. 2003, p.
211; Knick et al. 2003, p. 612; Connelly et al. 2004, p. 1-2). However,
fences can also benefit Gunnison sage-grouse by facilitating the
management of livestock forage use and distribution to achieve desired
habitat objectives (GSRSC 2005, pp. 211-213).
Sage-grouse frequently fly low and fast across sagebrush flats, and
fences can create a collision hazard resulting in direct mortality
(Call and Maser 1985, p. 22; Christiansen 2009, pp. 1-2). Not all
fences present the same mortality risk to sage-grouse. Mortality risk
appears to be dependent on a combination of factors including design of
fencing, landscape topography, and spatial relationship with seasonal
habitats (Christiansen 2009, pp. 1-2). This variability in fence
mortality rate and the lack of systematic fence monitoring make it
difficult to determine the magnitude of direct strike mortality impacts
to sage-grouse populations; however, in some cases the level of
mortality is likely significant to localized areas within populations.
Greater sage-grouse fence collisions during the breeding season in
Idaho were found to be relatively common and widespread, with
collisions being influenced by the technical attributes of the fences,
fence length and density, topography, and distance to nearest active
sage-grouse lek (Stevens 2011, pp. 102-107; Stevens et al. 2012a; p.
300; Stevens et al. 2012b, p. 1377). Stevens
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et al. (2012a; p. 299) found 41 of 60 recorded collisions (73 percent)
in spring of 2010 were less than 500m from a lek and only 1 collision >
500m from a lek, indicating that fences near leks containing certain
topographic properties may pose an increased risk to sage-grouse.
Although we expect the impacts of fences to Gunnison sage-grouse
are similar to those observed in greater sage-grouse, studies on fence
strike-related mortality in Gunnison sage-grouse are more limited. In
10 years of tracking and studying over 1,000 radio-collared sage-grouse
in Colorado, CPW has documented only two strike-related mortalities in
Gunnison sage-grouse due to fences (one confirmed case in Poncha Pass
attributed to bird release methods; and one unconfirmed case in the
Gunnison Basin); and only two strike-related mortalities in greater
sage-grouse due to fences (CPW 2013b, p. 11; Phillips and Griffin 2013,
pers. comm.). This information suggests that, in Colorado, direct
mortality of sage-grouse due to fence strikes is minimal, although
without a more thorough study, the anecdotal information may be
misleading.
Although the effects of direct strike mortality on populations are
not fully analyzed, fences are generally widespread across the
landscape. At least 1,540 km (960 mi) of fence are on BLM lands within
the Gunnison Basin (Borthwick 2005b, pers. comm.; BLM 2005a, 2005e) and
an unquantified amount of fence is located on land owned or managed by
other landowners. Many miles of historic fence occurs on NPS lands,
some of which may be affecting Gunnison sage-grouse. As of 2013, the
NPS has removed 1.6 km (1 mi) of unnecessary fencing, and will continue
inventorying efforts for additional removal where fencing is not
needed. The NPS is also constructing 8.8 km (5.5 mi) of fence to
prevent cattle grazing on a retired portion of an allotment. The fence
is built to CPW suggested wildlife-friendly specifications with raptor
perch deterrents and marked fence wires. Fences are present within all
other Gunnison sage-grouse population areas as well, but we have no
quantitative information on the amount or types of fencing in these
areas.
Fence posts create perching places for raptors and corvids, which
may increase the ability of these birds to prey on sage-grouse (Braun
1998, p. 145; Oyler-McCance et al. 2001, p. 330; Connelly et al. 2004,
p. 13-12). This impact is potentially significant for sage-grouse
reproduction because corvids were responsible for more than 50 percent
of greater sage-grouse nest predations in Nevada (Coates 2007, pp. 26-
30). Greater sage-grouse avoidance of habitat adjacent to fences,
presumably to minimize the risk of predation, effectively results in
habitat fragmentation even if the actual habitat is not removed (Braun
1998, p. 145). Because of similarities in behavior and habitat use, the
response of Gunnison sage-grouse should be similar to that observed in
greater sage-grouse.
Summary of Fences
Fences contribute to habitat decline and increase the potential for
loss of individual grouse through collisions or enhanced predation.
Fences can also benefit Gunnison sage-grouse by facilitating better
management of livestock grazing forage use and distribution in
sagebrush habitats. Despite some fence removal, we expect that the
majority of existing fences will remain on the landscape indefinitely.
In the smaller Gunnison sage-grouse populations, fencing cumulatively
affects the ability of the species to persist. We also recognize that
fences are located throughout all Gunnison sage-grouse populations and
are, therefore, contributing to the decline of remaining habitat and
are a potential source of mortality within all populations. For these
reasons, fences are likely a contributing factor to the decline of
Gunnison sage-grouse populations, both directly and indirectly, and are
therefore a current and future threat to the species.
Invasive Plants
For the purposes of this rule, we define invasive plants as those
that are not native to an ecosystem and that have a negative impact on
Gunnison sage-grouse habitat. Invasive plants alter native plant
community structure and composition, productivity, nutrient cycling,
and hydrology (Vitousek 1990, p. 7) and may cause declines in native
plant populations through competitive exclusion and niche displacement,
among other mechanisms (Mooney and Cleland 2001, p. 5446). Invasive
plants reduce and can eliminate vegetation that sage-grouse use for
food and cover, and generally do not provide quality sage-grouse
habitat. Sage-grouse depend on a variety of native forbs and the
insects associated with them for chick survival, and on sagebrush,
which is used exclusively throughout the winter for food and cover. In
eastern Nevada, leks with post-fire invasive grasses showed reduced lek
recruitment and reduced annual survival of male greater sage-grouse as
compared to leks surrounded by native sagebrush habitats, despite
favorable rainfall and climatic conditions (Blomberg et al. 2012).
Reduced adult survival, reproduction, and recruitment at the local
levels may, in turn, negatively impact sage-grouse populations.
Along with replacing or removing vegetation essential to sage-
grouse, invasive plants negatively impact existing sage-grouse habitat.
They can create long-term changes in ecosystem processes, such as fire-
cycles (see discussion below under Fire in this Factor A analysis) and
other disturbance regimes that persist even after an invasive plant is
removed (Zouhar et al. 2008, p. 33). A variety of nonnative annuals and
perennials are invasive to sagebrush ecosystems (Connelly et al. 2004,
pp. 7-107 and 7-108; Zouhar et al. 2008, p 144). Cheatgrass is
considered most invasive in Wyoming big sagebrush communities (Connelly
et al. 2004, p. 5-9). Other invasive plants found within the range of
Gunnison sage-grouse that are reported to take over large areas
include: spotted knapweed (Centaurea maculosa), Russian knapweed
(Acroptilon repens), oxeye daisy (Leucanthemum vulgare), yellow
toadflax (Linaria vulgaris), and field bindweed (Convolvulus arvensis)
(BLM 2009a, p. 28, 36; Gunnison Watershed Weed Commission (GWWC) 2009,
pp. 4-6).
Although not yet reported to affect large expanses in the range of
Gunnison sage-grouse, the following weeds are also known to occur in
the species' range and have successfully invaded large expanses of
native wildlife habitats in other parts of western North America:
diffuse knapweed (Centaurea diffusa), whitetop (Cardaria draba),
jointed goatgrass (Aegilops cylindrica), and yellow starthistle
(Centaurea solstitialis). Other invasive plant species present within
the range of Gunnison sage-grouse that are problematic yet less likely
to overtake large areas include: Canada thistle (Cirsium arvense), musk
thistle (Carduus nutans), bull thistle (Cirsium vulgare), houndstongue
(Cynoglossum officinale), black henbane (Hyoscyamus niger), common
tansy (Tanacetum vulgare), and absinth wormwood (A. biennis) (BLM
2009a, p. 28, 36; GWWC 2009, pp. 4-6).
Cheatgrass impacts sagebrush ecosystems by potentially shortening
fire intervals from several decades, to as low as 3 to 5 years
(depending on sagebrush plant community type and site productivity),
perpetuating its own persistence and intensifying the role of fire
(Whisenant 1990, p. 4). Another study found that cheatgrass presence
can shorten fire intervals to less than 10 years resulting in the
elimination of
[[Page 69251]]
shrub cover and reducing the availability and quality of forb cover
(Connelly et al. 2004, p. 7-5). Elevated carbon dioxide levels
associated with climate change may increase the competitive advantage
(via increased growth and reproduction rates) of exotic annual grasses,
such as cheatgrass, in higher elevation areas, such as in Gunnison
sage-grouse range, where its current distribution is limited (Miller et
al. 2011, pp. 181-183). Decreased summer precipitation reduces the
competitive advantage of summer perennial grasses, reduces sagebrush
cover, and subsequently increases the likelihood of cheatgrass invasion
(Bradley 2009, pp. 202-204; Prevey et al. 2009, p. 11). Future
decreased summer precipitation could increase the susceptibility of
sagebrush areas in Utah and Colorado to cheatgrass invasion (Bradley
2009, p. 204).
A variety of restoration and rehabilitation techniques are used to
treat invasive plants, but they can be costly and are mostly unproven
and experimental at a large scale. No broad-scale cheatgrass
eradication method has yet been developed. Habitat treatments that
either disturb the soil surface or deposit a layer of litter increase
cheatgrass establishment in the Gunnison Basin when a cheatgrass seed
source is present (Sokolow 2005, p. 51). Rehabilitation and restoration
techniques for sagebrush habitats are mostly unproven and experimental,
raising further concerns about soil disturbance and removal of any
remaining sage-brush habitats. (Pyke 2011, p. 543). Therefore,
researchers recommend using habitat treatment tools, such as brush
mowers, with caution and suggest that treated sites should be monitored
for increases in cheatgrass emergence (Sokolow 2005, p. 49).
Invasive Plants in the Gunnison Basin Population Area
Quantifying the total amount of Gunnison sage-grouse habitat
impacted by invasive plants is difficult due to differing sampling
methodologies, incomplete sampling, inconsistencies in species sampled,
and varying interpretations of what constitutes an infestation (Miller
et al., 2011, pp. 155-156). Cheatgrass has invaded areas in the
Gunnison sage-grouse range, supplanting sagebrush habitat in some areas
(BLM 2009a, p. 60). However, we do not have a reliable estimate of the
amount of area occupied by cheatgrass in the range of Gunnison sage-
grouse. While not ubiquitous, cheatgrass is found at numerous locations
throughout the Gunnison Basin (BLM 2009a, p. 60) and has been
identified as an impact to sage-grouse habitat in that population
(GSRSC 2005, p. 78).
Cheatgrass infestation within a particular area can range from a
small number of individuals scattered sparsely throughout a site, to
complete or near-complete understory domination of a site. Cheatgrass
has increased throughout the Gunnison Basin in the last decade and is
becoming increasingly detrimental to sagebrush community types (BLM
2009a, p. 7). Currently in the Gunnison Basin, cheatgrass attains site
dominance most often along roadways; however, other highly disturbed
areas have similar cheatgrass densities. In the Gunnison Basin,
cheatgrass is currently present in almost every grazing allotment in
Gunnison sage-grouse occupied habitat; and other invasive plant
species, such as Canada thistle, black henbane, spotted knapweed,
Russian knapweed, kochia (Kochia scoparia), bull thistle, musk thistle,
oxeye daisy, yellow toadflax and field bindweed, are found in riparian
areas and roadsides (BLM 2009a, p. 7).
Weed control efforts in the Gunnison Basin vary by area and agency
or organization. NPS weed control efforts have been successful at
reducing weeds (undesirable plant species, typically including exotic
or introduced species) in targeted areas. Gunnison County, the Gunnison
Basin Weed Commission, and other partners aggressively treat and
control weeds on all lands in the Gunnison Basin. From 2006 to 2012, a
total of 517 ha (1,280 ac) of land was treated for weeds in and near
occupied habitat for Gunnison sage-grouse (Gunnison County 2013a, p.
105), however it is unclear what portion of habitat this represents.
Gunnison County also recently adopted best management practices for
weeds identified in the Gunnison Basin CCA (Gunnison County 2013a, p.
78). Other measures related to weed control by Gunnison County include
reclamation standards and inspections (Gunnison County 2013a, p. 106),
educational programs and consultations (Gunnison County 2013a, p. 107).
While beneficial and necessary, such control efforts are likely
inadequate to address the threat of invasive plants, particularly in
the face of climate change and drought which are likely to intensify
the proliferation of these species in the range of Gunnison sage-
grouse.
Although disturbed areas most often contain the highest cheatgrass
densities, cheatgrass can readily spread into less disturbed and even
undisturbed habitat. A strong indicator for future cheatgrass invasion
is the proximity to current locations (Bradley and Mustard 2006, p.
1146) as well as summer, annual, and spring precipitation, and winter
temperature (Bradley 2009, p. 196). Although we lack the information to
make a detailed determination on the actual extent or rate of increase,
given its invasive nature, it appears that cheatgrass and its negative
influence on Gunnison sage-grouse will increase in the Gunnison Basin
in the future due to future human disturbances, potential exacerbation
from climate change interactions, and the lack of success to date with
control efforts at broad scales. Based on experience from other areas
in sagebrush ecosystems concerning the rapid spread of cheatgrass and
the shortened fire return intervals that can result, the spread of
cheatgrass within Gunnison sage-grouse habitat and the negative effects
to Gunnison sage-grouse populations will likely increase over time.
Invasive Plants in All Other Population Areas
Cheatgrass is present throughout much of the San Miguel Basin
population area (BLM 2005c, p. 6), but is most abundant in the Dry
Creek Basin area (CDOW 2005, p. 101), which comprises 62 percent of the
San Miguel Basin population. It is also present in the five Gunnison
sage-grouse subpopulations east of Dry Creek Basin, although at much
lower densities that do not currently pose a serious threat to Gunnison
sage-grouse (CDOW 2005, p. 101).
Invasive species are present at low levels in the Monticello group
(San Juan County GSGWG 2005, p. 20). However, there is no evidence that
they are affecting the population.
Cheatgrass dominates 10-15 percent of the sagebrush understory in
the current range of the Pi[ntilde]on Mesa population (Lambeth 2005,
pers. comm.). It occurs in the lower elevation areas below Pi[ntilde]on
Mesa that were formerly Gunnison sage-grouse range. Cheatgrass invaded
two small prescribed burn areas in or near occupied habitat conducted
in 1989 and 1998 (BLM 2005d, p. 6), and continues to be a concern with
new ground-disturbing projects. Within the Pi[ntilde]on Mesa
population, 520 ha (1,284 ac) of BLM lands are currently mapped with
cheatgrass as the dominant species (BLM 2009a, p. 3). This is not a
comprehensive inventory of cheatgrass occurrence, as it only includes
areas where cheatgrass dominates the plant community and does not
include areas where the species is present at lower densities.
[[Page 69252]]
Invasive plants, especially cheatgrass, occur primarily along
roads, other disturbed areas, and isolated areas of untreated
vegetation in the Crawford population area. According to BLM (2005c,
p.6), in the Crawford population area, the threat of cheatgrass may be
greater than all other nonnative species combined and could be a major
limiting factor when and if disturbance is used to improve habitat
conditions, unless mitigated.
Cheatgrass distribution has not been comprehensively mapped for the
Monticello-Dove Creek population area; however, cheatgrass is beginning
to be assessed on a site-specific and project-level basis. No
significant invasive plant occurrences are currently known in the
Poncha Pass population area.
Summary of Invasive Plants
Invasive plants negatively impact Gunnison sage-grouse primarily by
reducing or eliminating native vegetation that sage-grouse require for
food and cover, resulting in habitat decline. Although invasive plants,
especially cheatgrass, have affected some Gunnison sage-grouse habitat,
the impacts do not currently appear to be threatening individual
populations or the species rangewide. However, invasive plants continue
to expand their range, facilitated by ground disturbances such as fire,
grazing, and human infrastructure. Climate change will likely alter the
range of individual invasive species, accelerating the decline of
sagebrush communities. Even with treatments, given the history of
invasive plants on the landscape, and our continued inability to
control such species, invasive plants will persist and will likely
continue to spread throughout the range of the species indefinitely.
Although currently not a major threat to the persistence of Gunnison
sage-grouse at the species level, we anticipate invasive species to
become an increasing threat to the species in the future, particularly
when considered in conjunction with future climate projections and
potential changes in sagebrush plant community composition and
dynamics.
Fire
Mountain big sagebrush, the most important and widespread sagebrush
species for Gunnison sage-grouse, is killed by fire and can require
decades to recover. In nesting and wintering sites, fire causes direct
loss of habitat due to reduced cover and forage (Call and Maser 1985,
p. 17), with effects likely lasting 75 years or longer until sagebrush
recovers (Baker 2011, p. 16). While there may be limited instances
where burned habitat is beneficial (via prescribed fire or wildfire),
these gains are lost if alternative sagebrush habitat is not readily
available (Woodward 2006, p. 65). Another study (Baker 2013, p. 8)
suggested that prescribed burning in sagebrush habitat may be
detrimental, given the already limited range of Gunnison sage-grouse
(see above sections, Current Distribution and Population Estimates, and
Factor A introduction). Findings from that study indicated that
historical fire regimes in Gunnison sage-grouse range resulted in large
areas of contiguous sagebrush across the landscape when Gunnison sage-
grouse were more widespread and abundant. Fire treatments to thin or
reduce sagebrush, with its potential negative effects, would not be as
beneficial to the species as efforts made to expand areas of contiguous
sagebrush (Baker 2013, pp. 1, 8). Likewise, using fire to remove all
trees in sagebrush habitats is likely not appropriate, based on the
historical presence of pi[ntilde]on-juniper in these communities.
Pi[ntilde]on-juniper abundance likely fluctuated over time in response
to fire, at times occupying approximately 20 percent of the sagebrush
landscape (Baker 2013, p. 8). Thus, on the whole, we conclude that fire
negatively affects Gunnison sage-grouse and its habitat.
The nature of historical fire patterns in sagebrush communities,
particularly in Wyoming big sagebrush, is not well understood, and a
high degree of variability likely occurred (Miller and Eddleman 2001,
p. 16; Zouhar et al. 2008, p. 154; Baker 2011, p. 195). In general,
mean fire return intervals in low-lying, xeric (dry) big sagebrush
communities range from over 100 to 350 years, with return intervals
from 50 to over 200 years in more mesic (wet) areas, at higher
elevations, during wetter climatic periods, and in locations associated
with grasslands (Baker 2006, p. 181; Mensing et al. 2006, p. 75; Baker
2011, pp. 194-195; Miller et al. 2011, p. 166).
Herbaceous understory vegetation plays a critical role throughout
the breeding season as a source of forage and cover for Gunnison sage-
grouse females and chicks. The response of herbaceous understory
vegetation to fire varies with differences in species composition, pre-
burn site condition, fire intensity, and pre- and post-fire patterns of
precipitation. Any beneficial flush of perennial grasses and forbs
following fire in sagebrush communities is often minimal and lost after
only a few years, with little difference in herbaceous vegetation
between burned and unburned sites, but reduced sagebrush in burned
sites (Cook et al. 1994, p. 298; Fischer et al. 1996a, p. 196; Crawford
1999, p. 7; Wrobleski 1999, p. 31; Nelle et al. 2000, p. 588; Paysen et
al. 2000, p. 154; Wambolt et al. 2001, p. 250).
In addition to altering plant community structure through shrub
removal and potential weed invasion, fires can influence invertebrate
food sources (Schroeder et al. 1999, p. 5). Studies in greater sage-
grouse habitats indicate fire indeed influences the abundance of
important insect species (Fischer et al. 1996a, p. 196; Nelle et al.
2000, p. 589; Pyle and Crawford 1996, p. 322). However, the response
(positive or negative) and duration of those effects, and subsequent
recovery of insect populations, varied widely between studies and
areas. Therefore, although the best available information indicates
that fire may influence sage-grouse survival by altering the
availability of insect prey, the magnitude of those effects is
uncertain.
The invasion of the exotic annual grass cheatgrass increases fire
frequency within the sagebrush ecosystem (Zouhar et al. 2008, p. 41;
Miller et al. 2011, p. 170). As described in the previous section
(Invasive Species), cheatgrass readily invades sagebrush communities,
especially disturbed sites, and changes historical fire patterns by
providing an abundant and easily ignitable fuel source that facilitates
fire spread. While sagebrush is killed by fire and is slow to
reestablish, cheatgrass recovers within 1 to 2 years of a fire event
(Young and Evans 1978, p. 285). This annual recovery leads to a readily
burnable fuel source and ultimately a reoccurring fire cycle that
prevents sagebrush reestablishment (Eiswerth et al. 2009, p. 1324). The
extensive distribution and highly invasive nature of cheatgrass poses
increased risk of fire and permanent loss of sagebrush habitat, as
areas disturbed by fire are highly susceptible to further invasion and
ultimately habitat conversion to an altered community state. For
example, Link et al. (2006, p. 116) show that risk of fire increases
from approximately 46 to 100 percent when ground cover of cheatgrass
increases from 12 to 45 percent or more. However, BLM (2013b, p. 1-7)
noted that changes in fire frequency due to cheatgrass invasion, such
as those observed in the Great Basin region of the western United
States, have not been observed on BLM lands in Gunnison sage-grouse
range.
As discussed above, there are numerous potential negative effects
of fire to sagebrush habitat and, presumably, Gunnison sage-grouse. A
clear positive response of Gunnison or greater sage-grouse to fire has
not been
[[Page 69253]]
demonstrated (Braun 1998, p. 9). The few studies that have suggested
fire may be beneficial for greater sage-grouse were primarily conducted
in mesic areas used for brood-rearing (Klebenow 1970, p. 399; Pyle and
Crawford 1996, p. 323; Gates 1983, in Connelly et al. 2000c, p. 90;
Sime 1991, in Connelly et al. 2000a, p. 972). In this type of habitat,
small fires may maintain a suitable habitat mosaic by reducing shrub
encroachment and encouraging understory, herbaceous growth. However,
without available nearby sagebrush cover, the utility of these sites is
questionable. This is especially true within the six small Gunnison
sage-grouse populations, where fire could further degrade the remaining
habitat. More recent research indicated that, due to the fragmented
nature of remaining sagebrush habitat across the species' range,
prescribed fire may be inappropriate if the goal is to improve
sagebrush conditions and overall habitat quality for the species (Baker
2013, p. 8).
Fire in the Gunnison Basin Population Area
Six prescribed burns have occurred on BLM lands in the Gunnison
Basin since 1984, totaling approximately 409 ha (1,010 ac) (BLM 2009a,
p. 35). The fires created large sagebrush-free areas that were further
degraded by poor post-burn livestock management (BLM 2005a, p. 13). As
a result, these areas are less suitable as Gunnison sage-grouse
habitat. Approximately 8,470 ha (20,930 ac) of prescribed burns
occurred on Forest Service lands in the Gunnison Basin since 1983 (USFS
2009, p. 1). A small wildfire on BLM lands near Hartman Rocks burned 8
ha (20 ac) in 2007 (BLM 2009a, p. 35). The NPS completed a prescribed
burn on the north rim of the Black Canyon of the National Park in mixed
montane shrub and mountain big sagebrush communities to remove invading
juniper trees. Very few mountain big sagebrush were killed as a result
of the burn. The total area of occupied Gunnison sage-grouse habitat in
the Gunnison Basin burned in recent decades is approximately 8,887 ha
(21,960 ac), which constitutes 1.5 percent of the occupied Gunnison
sage-grouse habitat area. Cumulatively, this 1.5 percent area equates
to a relatively small amount of habitat burned over a period of nearly
three decades. This information suggests that there has not been a
demonstrated change in fire cycle in the Gunnison Basin population area
to date. The Nature Conservancy et al. (2011, p. 12) predicts that, due
to climate change, wildfire frequency and severity will increase in the
Gunnison Basin (see Climate Change section in this Factor A analysis).
However, CPW recently completed a literature review regarding fire in
high elevation Intermountain sage-brush basins, such as the Gunnison
Basin, and concluded that the probability of catastrophic fire in these
areas in the future is low, due to historic fire return intervals, the
low number of lightning strikes in the Gunnison Basin, and a low
relative risk of cheatgrass invasion after fires (CPW 2014g, Attachment
2).
Fire in All Other Population Areas
Two prescribed burns conducted in 1986 (105 ha (260 ac)) and 1992
(140 ha (350 ac)) on BLM land in the San Miguel Basin on the north side
of Dry Creek Basin had localized negative impacts on Gunnison sage-
grouse. The burns were conducted for big game forage improvement, but
the sagebrush died and was largely replaced with weeds (BLM 2005b, pp.
7-8). The Burn Canyon wildfire in the Dry Creek Basin and Hamilton Mesa
areas burned 890 ha (2,200 ac) in 2000. Three wildfires have occurred
in Gunnison sage-grouse habitat since 2004 on lands managed by the BLM
in the Crawford, Cerro Summit-Cimarron-Sims Mesa, and San Miguel Basin
population areas. There have been no fires since 2004 on lands managed
by the BLM within the Monticello-Dove Creek population. Because these
fires were mostly small in size, we do not believe they resulted in
substantial impacts to Gunnison sage-grouse at the species level.
Several wildfires near or within the Pi[ntilde]on Mesa population
area have occurred in the past 20 years. One fire burned a small amount
of occupied Gunnison sage-grouse habitat in 1995, and several fires
burned in potential Gunnison sage-grouse habitat. Individual burned
areas in this population ranged from 3.6 ha (9 ac) to 2,160 ha (5,338
ac). A wildfire in 2009 burned 1,053 ha (2,602 ac), predominantly
within vacant or unknown Gunnison sage-grouse habitat (suitable habitat
for sage-grouse that is separated from occupied habitats that has not
been adequately inventoried, or without recent documentation of grouse
presence) near the Pi[ntilde]on Mesa population.
Since 2004, a single 2.8-ha (7-ac) wildfire occurred in the Cerro
Summit-Cimarron-Sims Mesa population area, and two prescribed fires,
both less than 12 ha (30 ac), were implemented in the San Miguel
population area. No fire activity is reported within occupied Gunnison
sage-grouse habitat in the last two decades in the Poncha Pass
population area (CDOW 2009b, pp. 125-126) or the Monticello-Dove Creek
population area (CDOW 2009b, p. 75; UDWR 2009, p. 5). Although fire can
have devastating effects on Gunnison sage-grouse habitats, as discussed
above, because fires have burned primarily outside of occupied Gunnison
sage-grouse habitat in the Pi[ntilde]on Mesa population area and fire
has been recently absent or minimal in most other population areas,
fire has not resulted in substantial impacts to Gunnison sage-grouse in
these population areas.
Summary of Fire
Fires can cause the proliferation of weeds and can degrade suitable
sage-grouse habitat, which may not recover to suitable conditions for
decades, if at all (Pyke 2011, p. 539). Recent fires in Gunnison sage-
grouse habitat were mostly small in size and did not result in
substantial impacts to Gunnison sage-grouse, and there has been no
obvious change in fire cycle in any Gunnison sage-grouse population
area to date. Therefore, we do not consider fire to be a current threat
to Gunnison sage-grouse. While the best available scientific
information does not currently allow us to predict the extent or
location of future fire events, it does indicate that fire frequency
may increase in the future as a result of cheatgrass encroachment on
the sagebrush habitat and the projected effects of climate change (see
Invasive Plants and Climate Change discussions, above and below in this
Factor A analysis, respectively). Fire is, therefore, likely to become
a threat to Gunnison sage-grouse in the future.
Climate Change
Our analyses under the Act include consideration of ongoing and
projected changes in climate and its associated effects. The terms
``climate'' and ``climate change'' are defined by the Intergovernmental
Panel on Climate Change (IPCC). ``Climate'' refers to the mean and
variability of different types of weather conditions over time, with 30
years being a typical period for such measurements, although shorter or
longer periods also may be used (IPCC 2007, p. 78; IPCC 2013, p. 1450).
The term ``climate change'' thus refers to a change in the mean or
variability of one or more measures of climate (e.g., temperature or
precipitation) that persists for an extended period, typically decades
or longer, whether the change is due to natural variability, human
activity, or both (IPCC 2007, p. 78; IPCC 2013, p. 1450). Various types
of changes in climate can have direct or indirect effects on species.
These effects
[[Page 69254]]
may be positive, neutral, or negative and they may change over time,
depending on the species and other relevant considerations, such as the
effects of interactions of climate with other variables (e.g., habitat
fragmentation) (IPCC 2007, pp. 8-14, 18-19). In our analyses, we use
our expert judgment to weigh relevant information, including
uncertainty, in our consideration of various aspects of climate change.
According to the IPCC, ``Warming of the climate system in recent
decades is unequivocal, as is now evident from observations of
increases in global average air and ocean temperatures, widespread
melting of snow and ice, and rising global sea level'' (IPCC 2007, p.
1). Average Northern Hemisphere temperatures during the second half of
the 20th century were very likely higher than during any other 50-year
period in the last 500 years and likely the highest in at least the
past 1,300 years (IPCC 2007, p. 30). Over the past 50 years, cold days,
cold nights, and frosts have become less frequent over most land areas,
and hot days and hot nights have become more frequent. Heat waves have
become more frequent over most land areas, and the frequency of heavy
precipitation events has increased over most areas (IPCC 2007, p. 30).
For the southwestern region of the United States, including western
Colorado, warming is occurring more rapidly than elsewhere in the
country (Karl et al. 2009, p. 129). Annual average temperature in west-
central Colorado increased about 1.11 [deg]C (2[emsp14][deg]F) over the
past 30 years, but high variability in annual precipitation precludes
the detection of long-term precipitation trends (Ray et al. 2008, p.
5). Under high greenhouse gas emission scenarios, future projections
for the southwestern United States show increased probability of
drought (Karl et al. 2009, pp. 129-134), and the number of days over 32
[deg]C (90[emsp14][deg]F) could double by the end of the century (Karl
et al. 2009, p. 34). Climate models predict annual temperature increase
of approximately 2.2 [deg]C (4[emsp14][deg]F) in the Southwest by 2050,
with summers warming more than winters (Ray et al. 2008, p. 29).
Projections also show declines in snowpack across the West with the
most dramatic declines at lower elevations (below 2,500 m (8,200 ft))
(Ray et al. 2008, p. 29).
Colorado's complex, mountainous topography results in a high degree
of spatial variability across the State. As a result, predicting
localized climate changes is challenging for mountainous areas because
current global climate models are unable to capture this variability at
local or regional scales (Ray et al. 2008, pp. 7, 20). To obtain
climate projections specific to the range of Gunnison sage-grouse, we
requested a statistically downscaled model from the National Center for
Atmospheric Research for a region covering western Colorado. The
resulting projections indicate the highest probability scenario is that
average summer (June through September) temperature could increase by
2.8 [deg]C (5.1[emsp14][deg]F), and average winter (October through
March) temperature could increase by 2.2 [deg]C (4.0[emsp14][deg]F) by
2050 (University Corporation for Atmospheric Research (UCAR) 2009, pp.
1-15). Annual mean precipitation projections for Colorado are unclear;
however, data indicate a shift towards increased winter precipitation
and decreased spring and summer precipitation (Ray et al. 2008, p. 34;
Karl et al. 2009, p. 30). Similarly, there is a high probability of a 5
percent increase in average winter precipitation and a 5 percent
decrease in average spring-summer precipitation in 2050 (UCAR 2009, p.
15). These predicted changes in precipitation and temperature will
likely alter sagebrush plant community composition and dynamics, but to
what degree is uncertain.
For sagebrush, spring and summer precipitation comprises the
majority of the moisture available to the species; thus, the
interaction between reduced precipitation in the spring-summer growing
season and increased summer temperatures will likely decrease growth of
mountain big sagebrush. This effect could result in a significant long-
term reduction in the distribution of sagebrush communities (Miller et
al. 2011, pp. 171-174). In the Gunnison Basin, increased summer
temperature was strongly correlated with reduced growth of mountain big
sagebrush (Poore et al. 2009, p. 558). Based on these results and the
likelihood of increased winter precipitation falling as rain rather
than snow, and the corresponding increase in evaporation and decrease
in deep soil water recharge, Poore et al. (2009, p. 559) predict
decreased growth of mountain big sagebrush, particularly at the lower
elevation limit of the species. Because Gunnison sage-grouse are
sagebrush obligates, loss of sagebrush would result in a reduction of
suitable habitat and negatively impact the species. The interaction of
climate change with other stressors likely has impacted and will impact
the sagebrush steppe ecosystem where Gunnison sage-grouse occur.
Climate change is likely to alter fire frequency, community
assemblages, and the ability of nonnative species to proliferate.
Increasing temperature as well as changes in the timing and amount of
precipitation will alter the competitive advantage among plant species
(Miller et al. 2011, pp. 175-179), and may shift individual species and
ecosystem distributions (Bachelet et al. 2001, p. 174). Temperature
increases may increase the competitive advantage of cheatgrass in
higher elevation areas where its current distribution is limited
(Miller et al. 2011, p. 182). Decreased summer precipitation reduces
the competitive advantage of summer perennial grasses, reduces
sagebrush cover, and subsequently increases the likelihood of
cheatgrass invasion (Prevey et al. 2009, p. 11). This impact could
increase the susceptibility of areas within Gunnison sage-grouse range
to cheatgrass invasion (Bradley 2009, p. 204), which would reduce the
overall cover of native vegetation, reduce habitat quality, and
potentially decrease fire return intervals, all of which would
negatively affect the species. In addition, The Nature Conservancy et
al. (2011, p. 12) predicted increased fire frequency and severity in
the Gunnison Basin associated with climate change.
Under drought conditions, plants generally are less vigorous and
less successful in reproduction, and may require several years to
recover following drought (Weltzin et al. 2003, p. 946). Increased
drought and shifts in the magnitude and timing of temperature and
precipitation could reduce herbaceous and insect production within
Gunnison sage-grouse habitats.
A recent climate change vulnerability index applied to Gunnison
sage-grouse ranked the species as ``highly vulnerable'' to modeled
climate change by the year 2050 (The Nature Conservancy 2011, p. 11).
The mechanism of this vulnerability was the degradation of high-quality
brood-rearing habitat due to the loss of adequate moisture for the
maintenance of mesic meadows, springs, seeps, and riparian areas, as
well as potential changes in the fire regime and subsequent loss of
sagebrush cover. A reduction in the quality and amount of these
resources, including brood-rearing habitats in particular, will likely
affect key demographic processes such as the productivity of breeding
hens and survival of chicks and juveniles, resulting in reduced
population viability. A recent analysis indicated juvenile survival was
the most influential vital rate affecting population growth rates in
the Gunnison Basin (Davis 2012, pp. 89). Drought conditions from 1999
through 2003 were closely associated with reductions in the sizes of
all Gunnison sage-grouse populations, including the
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Gunnison Basin (CDOW 2009b, entire). While geographic and microclimatic
variation in the Gunnison Basin may provide some degree of local
variation and, perhaps, local population redundancy to resist
environmental pressures, past drought has had widespread impacts on
this population, as indicated by negative trends in nearly all lek
complexes during that period (see Drought in this Factor A analysis;
and Resiliency, Redundancy, and Representation in the Factor E analysis
for further discussion on this topic).
Summary of Climate Change
Climate change predictions are based on models with assumptions,
and there are uncertainties regarding the magnitude of associated
climate change parameters such as the amount and timing of
precipitation and seasonal temperature changes. There is also
uncertainty as to the magnitude of effects of predicted climate
parameters on sagebrush plant community dynamics. These factors make it
difficult to predict to what extent climate change will affect Gunnison
sage-grouse. We recognize that climate change has the potential to
alter Gunnison sage-grouse habitat by facilitating an increase in the
distribution of cheatgrass and concurrently increasing the potential
for wildfires, and reducing herbaceous vegetation and insect production
in drought years, which would have negative effects on Gunnison sage-
grouse. We do not consider climate change to be a current threat to
Gunnison sage-grouse because of the uncertainties described above.
However, based on the best available information on climate change
projections over the next 35 years or so, climate change has the
potential to alter important seasonal habitats and food resources of
Gunnison sage-grouse, the distribution and extent of sagebrush, and the
occurrence of invasive weeds and associated fire frequencies. Climate
change effects, including increased drought, are also predicted in the
Gunnison Basin population. Therefore, we find that climate change is a
substantial future threat to Gunnison sage-grouse rangewide.
Mineral Development
Mineral commodity development on Federal lands includes three
primary types: Leasable, locatable, and salable minerals. Below, we
define each type of mineral development and assess the scope of those
activities and their potential impacts across Gunnison sage-grouse
range.
Leasable Mineral Development
Leasable minerals are defined and administered under the Mineral
Leasing Act of 1920, as amended, and include oil and gas, oil shale,
coal, geothermal, potash, sodium, and sulfur. In this section, we first
discuss the effects of oil and gas development on sage-grouse and sage-
grouse habitats in general. We then evaluate potential and ongoing
development of oil and gas, coal and coal-bed methane, and other
leasable minerals across the range of Gunnison sage-grouse. Available
scientific information on the effects of mineral development to sage-
grouse is related primarily to oil and gas development. However, in
terms of effects on the species and its habitat, we expect other types
of mineral development to have impacts similar to that of oil and gas
development, though those impacts may vary in magnitude and scope.
Effects of Oil and Gas Development
Oil and gas, or fluid mineral, development for energy resources on
Federal (BLM and USFS) lands is regulated by the BLM (see Factor D
analysis below for a more thorough discussion). The BLM (1999, p. 1)
has classified the area encompassing all Gunnison sage-grouse habitat
for its oil and gas potential. Two population areas, San Miguel Basin
and Monticello-Dove Creek, have areas with high potential, and one, the
Crawford population area, has medium potential. BLM classifies the oil
and gas potential for the remaining populations as low or none. San
Miguel County, where much oil and gas activity has occurred in the last
few years, ranked 9 out of 39 in Colorado counties producing natural
gas in 2009 (Colorado Oil and Gas Conservation Commission 2010a, p. 1)
and 29 of 39 in oil production in 2009 (Colorado Oil and Gas
Conservation commission 2010b, p. 2).
Energy development impacts sage-grouse and sagebrush habitats
through direct habitat loss from well pad construction, seismic
surveys, roads, powerlines and pipeline corridors, and indirectly from
noise, gaseous emissions, changes in water availability and quality,
and human presence. The interaction and intensity of effects could
cumulatively or individually lead to habitat degradation and
fragmentation (Suter 1978, pp. 6-13; Aldridge 1998, p. 12; Braun 1998,
pp. 144-148; Aldridge and Brigham 2003, p. 31; Knick et al. 2003, pp.
612, 619; Lyon and Anderson 2003, pp. 489-490; Connelly et al. 2004,
pp. 7-40 to 7-41; Holloran 2005, pp. 56-57; Holloran et al. 2007, pp.
18-19; Aldridge and Boyce 2007, pp. 521-522; Walker et al. 2007a, pp.
2652-2653; Zou et al. 2006, pp. 1039-1040; Doherty et al. 2008, p. 193;
Leu and Hanser 2011, pp. 270-271). Increased human presence resulting
from oil and gas development can also impact sage-grouse either through
avoidance of suitable habitat or disruption of breeding activities
(Braun et al. 2002, pp. 4-5; Aldridge and Brigham 2003, pp. 30-31;
Aldridge and Boyce 2007, p. 518; Doherty et al. 2008, p. 194). The
development of oil and gas resources requires surveys for economically
recoverable reserves, construction of well pads and access roads,
subsequent drilling and extraction, and transport of oil and gas,
typically through pipelines. Ancillary facilities can include
compressor stations, pumping stations, electrical generators and
powerlines (Connelly et al. 2004, p. 7-39; BLM 2007, p. 2-110). Surveys
for recoverable resources occur primarily through loud seismic
exploration activities. These surveys can result in the crushing of
vegetation. Well pads vary in size from 0.10 ha (0.25 ac) for coal-bed
natural gas wells in areas of level topography to greater than 7 ha
(17.3 ac) for deep gas wells and multi-well pads (Connelly et al. 2004,
p. 7-39; BLM 2007, p. 2-123). Pads for compressor stations require 5-7
ha (12.4-17.3 ac) (Connelly et al. 2004, p. 7-39). Individually,
impacts from well pads, infrastructure, and ancillary features may be
small; however, the cumulative impact of such development can be
significant.
The amount of direct habitat loss within an area of oil and gas
development is ultimately determined by well densities and the
associated loss from ancillary facilities. Roads associated with oil
and gas development were suggested as the primary impact to greater
sage-grouse due to their persistence and continued use even after
drilling and production ceased (Lyon and Anderson 2003, p. 489).
Declines in male greater sage-grouse lek attendance were reported
within 3 km (1.9 mi) of a well or haul road with a traffic volume
exceeding one vehicle per day (Holloran 2005, p. 40). Because of
reasons discussed previously, the effects of oil and gas development to
Gunnison sage-grouse are expected to be similar to those observed in
greater sage-grouse. Sage-grouse also may be at increased risk for
collision with vehicles simply due to the increased traffic associated
with oil and gas activities (Aldridge 1998, p. 14; BLM 2003, p. 4-222).
Habitat fragmentation resulting from oil and gas development
infrastructure, including access roads, may have greater effects on
sage-grouse than habitat loss associated with drill sites.
[[Page 69256]]
Energy development and associated infrastructure works cumulatively
with other human activity or development to decrease available habitat
and increase fragmentation. Greater sage-grouse leks had the lowest
probability of persisting (40-50 percent) in a landscape with less than
30 percent sagebrush within 6.4 km (4 mi) of the lek. These
probabilities were even less in landscapes where energy development
also was a factor (Walker et al. 2007a, p. 2652).
Oil and Gas Development Across the Gunnison Sage-Grouse Range--
As noted above, high oil and gas development potential exists in
the San Miguel Basin and Monticello-Dove Creek population areas, medium
potential exists in the Crawford population area, and low or no
potential exists in the remaining population areas. Approximately 33
percent of the Gunnison Basin population area was ranked as having low
oil and gas potential with the remainder having no potential for oil
and gas development (GSRSC 2005, p. 130). No Federal lands are
currently leased for oil and gas development within the Gunnison Basin
population area.
Energy development within the range of Gunnison sage-grouse is
occurring primarily in the San Miguel Basin and Dove Creek population
areas in Colorado. The San Miguel Basin and Monticello-Dove Creek
population areas occur in the Paradox Basin, a known oil and gas
producing region. The majority of oil and gas development and potential
in the Paradox Basin, however, is outside of Gunnison sage-grouse
habitat (Industrial Economics, Inc. (IEc) 2014, p. 5-2, and references
therein). In addition, to date, low levels of development and
production have occurred in this area relative to recent development in
other regions within the western U.S. Oil and gas production in San
Juan County, Utah, which includes the Monticello portion of occupied
range for Gunnison sage-grouse, has declined since the late 1980's (IEc
2014, p. 5-1 to 5-2, and references therein). In the San Miguel Basin,
approximately 8,000 acres are leased for oil and gas development in
occupied habitat on BLM land and, of that area, about 5,000 acres (63
percent) are producing (IEc 2014, p. 5-4, and references therein). The
entire San Miguel Basin population area has high potential for oil and
gas development (GSRSC 2005, p. 130).
Fluid mineral development in the Paradox Basin is currently taking
place on 44 active, producing, or permitted wells in occupied habitat
in the San Miguel and Monticello-Dove Creek populations. Of these, 38
active or producing wells occur in the San Miguel population area on
BLM land; 5 newly permitted wells occur on non-Federal land in the Dove
Creek population in Colorado; and 1 active well occurs on private land
in the Monticello population in Utah (IEc 2014, pp. 5-4 to 5-5, and
references therein). In the San Miguel population, most wells are in or
near the Dry Creek subpopulation area. The exact locations of potential
future wells are not known, but because the area is small, they will
likely lie within 3 km (2 mi) of one of only three leks in this area
(CDOW 2005, p. 108).
In the remainder of the Gunnison sage-grouse range, a total of 10
oil and gas wells occur in occupied habitat. Eight oil and gas wells
occur in the Gunnison Basin population area, and one in each of the
Crawford and Cerro Summit-Cimarron-Sims Mesa population areas (derived
from Colorado Oil and Gas Commission 2010, GIS dataset). We are not
aware of any new fluid mineral development in these or other population
areas since 2010. No oil and gas wells or Federal leases are within the
Pi[ntilde]on Mesa population area (BLM 2009a, p. 1), and no potential
for oil or gas exists in this area except for a small area on the
eastern edge of the largest habitat block (BLM 1999, p. 1; GSRSC 2005,
p. 130). The Crawford population is in an area with medium potential
for oil and gas development. A single Federal lease occurs on less than
1 percent of the Crawford population area (GSRSC 2005, p. 130). We are
not aware of any information which indicates that oil and gas
development is a threat to the Poncha Pass population. Based on the
best available information, we conclude that oil and gas development is
not a current or future threat to the Pi[ntilde]on Mesa, Crawford, or
Poncha Pass populations.
Since 2005, the BLM has deferred (temporarily withheld from lease
sales) federal parcels nominated for oil and gas leasing in occupied
Gunnison sage-grouse habitat in Colorado (see further discussion in
Factor D Federal Laws and Regulations). Even with this temporary
deferment, however, we expect energy development on public and private
lands in the San Miguel Basin and the Monticello-Dove Creek areas to
continue over the next 20 years based on the length of development and
production projects described in existing project and management plans.
Gas development may be negatively impacting a portion of the Dry Creek
subpopulation because this area contains some of the poorest habitat
and smallest grouse populations within the San Miguel population
((SMBGSWG) 2009, pp. 28 and 36). Overall, we believe that this stressor
is localized and, although it is likely to increase in the future, it
is not now, or likely to become a rangewide threat to the species in
the future.
Coal and Coal-bed Methane Development in All Population Areas
While coal resources and several active coal fields (Somerset,
Crested Butte, Grand Mesa, etc.) exist in the region, there are no
active coal operations in Gunnison sage-grouse habitat (Colorado
Division of Reclamation, Mining, and Safety (CDRMS) 2013), and
recoverable coal resources are limited in Gunnison sage-grouse range.
We have reviewed the best available scientific information regarding
the potential for development of any coal resources in the Gunnison
sage-grouse range, and found that it is unlikely in the near future due
to technological, geologic, economic, and other constraints (USFWS
2014a, entire). Therefore, we find that coal and coal-bed methane
development are not current or future threats to Gunnison sage-grouse.
Other Leasable Mineral Development
Potash exploration is currently underway in the Monticello-Dove
Creek population area, but outside of occupied habitat for Gunnison
sage-grouse. During 2009 and 2010, BLM received applications for 22
prospecting permits on approximately 40,000 acres of BLM land in this
area (outside of occupied habitat). Recently, BLM prepared an
Environmental Analysis for six proof-of-concept drill sites. The
company that submitted the application estimates that between 250,000
and two million tons of potash may be recovered per year for at least
20 years. If preliminary explorations determine that extraction is
feasible, potash development will likely follow (IEc 2014, p. 5-6).
However, because it is unknown where and to what extent development
would occur, the degree to which potash development would affect
Gunnison sage-grouse and its habitat is unknown at this time.
Summary of Leasable Mineral Development
The San Miguel Basin and Dove Creek populations are the only areas
within Gunnison sage-grouse range that currently have a moderate amount
of oil and gas production. However, impacts to Gunnison sage-grouse and
its habitat in this area are limited in scope relative to other regions
of oil and gas development within the western U.S. We recognize that
portions of the range, such as the Dry Creek subpopulation of
[[Page 69257]]
the San Miguel population, may currently be impacted by fluid mineral
development. However, current and potential leasable energy development
is limited to a small portion of the species' overall range. To date,
the majority of oil and gas development has occurred outside of
occupied habitat for Gunnison sage-grouse.
While the San Miguel, Monticello-Dove Creek, and Crawford
populations have high or medium potential for future development, the
potential for future development is low throughout the remaining
population areas, which represent the majority of the species' range.
While coal resources and several active coal fields exist in the
region, there are no active coal operations in Gunnison sage-grouse
habitat, and recoverable coal resources are limited in Gunnison sage-
grouse range (USFWS 2014a, entire). In the near future, there is a
potential for potash development in the Monticello-Dove Creek
population; however, the magnitude of the impacts (if any) of this
development on the species are unknown at this time (see above
discussion). Because of the localized scale of these impacts, we
consider leasable mineral development to be a threat of low magnitude
to species as a whole. However, given the small and isolated nature of
the populations where oil and gas development is most likely to occur,
oil and gas development is a current and future threat to those
populations.
Locatable and Salable Mineral Development in All Population Areas
Locatable minerals include both metallic minerals (gold, silver,
uranium, vanadium, lead, zinc, copper, etc.) and certain unique,
valuable non-metallic minerals (gemstones, fluorspar, mica, gypsum,
asbestos, mica, etc.). The Mining Law of 1872 governs the exploration,
purchase, and development of locatable minerals on mining claims. This
law grants citizens of the United States the opportunity to explore
for, discover, develop, and purchase certain valuable mineral deposits
on public domain minerals. Unpatented mining claims established under
the Mining Law of 1872 give the holder the right to mine locatable
minerals on Federal lands. Locating a mining claim requires discovery
of a valuable mineral through exploration. The BLM administers mining
claims and related notices and approvals on BLM and USFS lands. The BLM
reviews and approves a ``Plan of Operations'' for mining on Federal
lands resulting in surface disturbance of more than 5 acres, and, in
Colorado, financial warranty (e.g., cash bond) is required for
reclamation through the Colorado Division of Reclamation, Mining and
Safety (CDRMS). A mine operator need only file a ``Notice of Intent''
with BLM before proceeding with locatable mineral exploration or
prospecting resulting in surface disturbance of 5 acres or less.
Operators are required to provide financial warranty for reclamation
costs associated with disturbance from exploration, which is also filed
and held by the CDRMS. ``Casual use'' activities related to locatable
minerals on Federal lands that cause negligible disturbance (e.g., no
use of earth moving equipment or explosives) have no legal
requirements. The quantity and extent of casual use activities, and
thus the effects on Gunnison sage-grouse and its habitat, are unknown.
Salable minerals, or mineral materials, include sand, gravel,
stone, clay, pumice, cinders, and similar minerals. Salable minerals on
Federal lands are subject to mineral material disposal under the
Materials Act of 1947, as amended. Mining of these minerals entails a
sales contract or a free-use permit from the responsible Federal
agency.
The Service accessed CDRMS mine and mine claim data (CDRMS 2013,
entire) to evaluate mineral potential and development in Gunnison sage-
grouse occupied range in Colorado. The CDRMS's dataset includes both
active and terminated or expired mining permits since about 1984 to
present, including locatable and salable minerals. Our analysis found
that in Gunnison sage-grouse occupied habitat in Colorado, there are 19
active mining permits (``active'' means the permits are valid and
current, not necessarily that actual mining is occurring), comprising
324.07 acres. Of this number, our analysis found that 247.96 acres (77
percent) are in the Gunnison Basin population, and are associated
primarily with sand and gravel operations (USFWS 2014b, p. 1).
Fifty recently expired or terminated mining permits exist in
Gunnison sage-grouse occupied range in Colorado, affecting
approximately 256.5 acres. Again, the majority of area affected was in
the Gunnison Basin, including 194.1 acres (75.6 percent) associated
with sand and gravel, borrow material, and gold mining. Some of these
mining permit applications were withdrawn, or mining did not occur
(USFWS 2014b, p. 2).
Where mining has not yet been permitted or occurred, active
(recorded) mining claims indicate potential development of those
resources in the future, since identifying a claim requires discovery
of a valuable mineral. Currently, in Gunnison sage-grouse occupied
habitat in Colorado, there are 694 active mining claims, totaling
approximately 9,966 acres, or 1.15 percent of rangewide occupied
habitat. Approximately 7.79 percent and 2.10 percent of occupied
habitat in the San Miguel Basin and Dove Creek populations,
respectively, are under mining claims. For each of the other five
Gunnison sage-grouse populations, the area under mining claims is less
than 1 percent of total occupied habitat in those populations (USFWS
2014b, p. 3). These data indicate that mining potential and future
development is limited in scope in the range of Gunnison sage-grouse.
It is uncertain what proportion of these mining claims will be
developed in the future, and to what extent they will be developed.
Future development depends on economic and market conditions,
permitting requirements, and multiple other factors.
Future development of some mining claims, however, could affect
individual Gunnison sage-grouse or populations. Future development of
uranium mining claims in the San Miguel population area, in particular,
could result in impacts on this population of Gunnison sage-grouse and
its habitat. This area includes the Uravan Mineral Belt, which has
historically been the most productive uranium region in Colorado, and
provides an important national reserve of uranium (IEc 2014, pp. 5-1,
5-5 to 5-6). The Department of Energy, which is responsible for
managing uranium leasing and development, is currently in the process
of evaluating the continuation of existing uranium leases under a Draft
Programmatic Environmental Impact statement. In recent years, uranium
mining activity in this area has nearly ceased due to a decrease in
global uranium prices. One active uranium mine occurs in occupied
habitat in the San Miguel population. However, this mine is currently
not in production (IEc 2014, p. 5-5 to 5-6). Construction of the first
conventional uranium mill in 25 years, the Pi[ntilde]on Ridge Uranium
Mill, is proposed near, but outside of, occupied habitat in the San
Miguel Basin. However, this mill may not be built until uranium prices
increase (IEc 2014, p. 5-5 to 5-6). Such a project may result in
indirect impacts on Gunnison sage-grouse, though we cannot predict the
scope or magnitude of those impacts.
We were unable to acquire similar data for mining activity in the
State of Utah, and as a result we do not know the degree to which
mineral claims or mines overlap occupied habitat in the Monticello
population area. Published
[[Page 69258]]
maps indicate there are four small mines (less than 5 ac of disturbance
at any one time) on the periphery of occupied habitat in the Monticello
population area. These include two uranium mines and one flagstone mine
that are inactive; and one uranium/vanadium mine that was active as of
2008 (UGS 2008a, pp. 4-5, 7). The majority of uranium and vanadium
potential and past production in San Juan County is south-southeast of
the city of Monticello, Utah, outside of occupied habitat (UGS 2005,
entire). Several large mines (more than 5 ac of disturbance at any one
time), including uranium and copper (inactive and active) occur
northeast of Monticello, Utah (UGS 2008b, pp. 2, 5), outside the
species' range. This information indicates that the overall current and
potential development of locatable and salable minerals is very limited
in Gunnison sage-grouse occupied range in Utah.
Future mineral development, especially in seasonally important
habitats or in smaller or declining populations, will likely impact
Gunnison sage-grouse populations. Indirect effects such as functional
habitat loss associated with mineral operations, as well as impacts
from associated infrastructure, are also likely.
Summary of Locatable and Salable Mineral Development
Mining, especially in seasonally important habitats or in smaller
or declining populations, will likely impact Gunnison sage-grouse
populations. Indirect effects such as functional habitat loss
associated with mining operations, as well as impacts from associated
infrastructure, are also likely. However, currently active mines and
mining claims are limited in geographic scope, and thus are considered
a threat of low magnitude to Gunnison sage-grouse rangewide. If uranium
prices increase in the future, development in the San Miguel Basin
could potentially pose a threat to this already small and vulnerable
population of Gunnison sage-grouse.
Renewable Energy Development--Geothermal and Wind
Geothermal energy production is similar to oil and gas development
in that it requires surface exploration, exploratory drilling, field
development, and plant construction and operation, and likely results
in similar degrees of direct and functional habitat loss (see Effects
of Oil and Gas Development). Wells are drilled to access the thermal
source, and drilling can require 3 weeks to 2 months of continuous
activity (Suter 1978, p. 3), which may cause disturbance to sage-
grouse. The ultimate number of wells, and, therefore, potential loss of
habitat, depends on the thermal output of the source and expected
production of the plant (Suter 1978, p. 3). Pipelines are needed to
carry steam or superheated liquids to the generating plant, which is
similar in size to a coal- or gas-fired plant, resulting in further
habitat destruction and indirect disturbance. Direct habitat loss
occurs from well pads, structures, roads, pipelines and transmission
lines, and impacts would be similar to those described above for oil
and gas development. The development of geothermal energy requires
intensive human activity during field development and operation, which
could lead to habitat loss. Furthermore, geothermal development could
cause toxic gas release. The type and effect of these gases depends on
the geological formation in which drilling occurs (Suter 1978, pp. 7-
9). The amount of water necessary for drilling and condenser cooling
can be high. Local water depletions may be a concern if such use
results in the loss or degradation of brood-rearing habitat.
Geothermal Energy in the Gunnison Basin Population Area--
The entire Gunnison Basin, or 87 percent of rangewide occupied
habitat, is within a region of known geothermal potential (BLM and USFS
2010, p. 1). Currently, geothermal leases in the Gunnison Basin occur
in the same general vicinity on private, BLM, USFS, and Colorado State
Land Board lands, near Tomichi Dome and Waunita Hot Springs in
southeastern Gunnison County. The cumulative area of geothermal leases
in occupied habitat is approximately 3,399 ha (8,400) ac, including
1,861 ha (4,600 ac) on BLM land, and 1,538 ha (3,800 ac) on USFS land.
This comprises 1.4 percent of occupied habitat in the Gunnison Basin.
In 2012, all of the leased area described above was acquired by a
conservation group that does not intend to develop the resource.
Geothermal leases are issued for 10 years and may be extended for two
five-year periods (IEc 2014, p. 7-2, and references therein).
Therefore, we do not anticipate geothermal development of these leases
prior to 2032. If geothermal development occurs on the leases in the
future, it would likely negatively impact Gunnison sage-grouse through
habitat loss and disturbance of birds. One active lek and two inactive
leks are located within the leased parcels. In addition, six active
leks and four inactive leks are within 6.4 km (4 mi) of the lease
application parcels indicating that a high degree of seasonal use may
occur within the area surrounding these leks (GSRSC 2005, p. J-4). A
significant amount of high-quality Gunnison sage-grouse nesting habitat
also exists on and near the leased parcels (Aldridge et al. 2012, p.
402). Thus, geothermal development is a potential future threat to the
Gunnison Basin population.
Geothermal Energy in All Other Population Areas--
Geothermal development potential exists in the San Luis Valley
including portions of the Poncha Pass population area. No geothermal
leases currently exist in the San Luis Valley or Poncha Pass areas (BLM
2012b, entire; IEc 2014, p. 7-2). Further, the 2013 BLM San Luis Valley
Geothermal Amendment to their Resource Management Plan prohibits all
geothermal development within Gunnison sage-grouse occupied habitat
through a no surface occupancy stipulation (BLM 2012b, entire; BLM
2013e, p. 2-11; BLM 2013f, entire). Therefore, geothermal development
does not appear to be a current or future threat to Gunnison sage-
grouse in the Poncha Pass population. We found no other information on
the presence of existing, pending, or authorized geothermal energy
sites, nor any other areas with high potential for geothermal energy
development, within any other Gunnison sage-grouse population area.
Thus, at this time, geothermal development outside the Gunnison Basin
does not appear to be a threat to Gunnison sage-grouse.
Wind Energy Development
Most published reports of the effects of wind development on birds
focus on the risks of collision with towers or turbine blades. However,
a recent study conducted in south-central Wyoming examined the short-
term behavioral response of greater sage-grouse to wind energy
development (LeBeau 2012, entire). In the two years following
construction, greater sage-grouse were not avoiding habitats near wind
turbines, and even selected for habitats closer to turbines during the
summer months. Male lek attendance was apparently unaffected by wind
energy development in the area. However, the author cautioned that
these responses may have been due to typically high site fidelity of
sage-grouse despite anthropogenic disturbances, and that impacts may
not be realized until two to 10 years following development, similar to
oil and gas development in sage-grouse habitats. The study reported
that other fitness and vital rates such as nesting and brood survival
rates
[[Page 69259]]
declined near constructed wind turbines, potentially as a result of
increased predation and edge effects created by wind energy
infrastructure (LeBeau 2012, entire).
Avoidance of human-made structures such as powerlines and roads by
sage-grouse and other prairie grouse is well-documented (Holloran 2005,
p. 1; Pruett et al. 2009, pp. 1255-1256) (also see Roads and Powerlines
sections above). Wind power requires many of the same features for
construction and operation as do nonrenewable energy resources.
Therefore, we anticipate that potential impacts from habitat decline
due to roads and powerlines, noise, and increased human presence
(Connelly et al. 2004, pp. 7-40 to 7-41) will generally be similar to
those discussed above for mineral energy development.
Wind farm development begins with site monitoring and collection of
meteorological data to accurately characterize the wind regime.
Turbines are installed after the meteorological data indicate the
appropriate siting and spacing. Roads are necessary to access the
turbine sites for installation and maintenance. Each turbine unit has
an estimated footprint of 0.4 to 1.2 ha (1 to 3 ac) (BLM 2005e, pp.
3.1-3.4). One or more substations may be constructed depending on the
size of the farm. Substation footprints are 2 ha (5 ac) or less in size
(BLM 2005e, p. 3.7).
The average footprint of a turbine unit is relatively small from a
landscape perspective. Turbines require careful placement within a
field to avoid loss of output from interference with neighboring
turbines. Spacing improves efficiency but expands the overall footprint
of the field. Sage-grouse populations are impacted by the direct loss
of habitat associated with the construction of access roads, as well as
indirect loss of habitat and behavioral avoidance of the wind turbines.
Sage-grouse could be killed by flying into turbine rotors or towers
(Erickson et al. 2001, entire), although reported collision mortalities
have been few. One sage-grouse was found dead within 45 m (148 ft) of a
turbine on the Foote Creek Rim wind facility in south-central Wyoming,
presumably from flying into a turbine (Young et al. 2003, Appendix C,
p. 61). This is the only known sage-grouse mortality at this facility
during three years of monitoring. We have no recent reports of sage-
grouse mortality due to collisions with wind turbines; however, many
facilities may not be monitored. No deaths of gallinaceous birds were
reported in a comprehensive review of avian collisions and wind farms
in the United States; the authors hypothesized that the average tower
height and flight height of grouse, and diurnal migration habitats of
some birds minimized the risk of collision (Johnson et al. 2000, pp.
ii-iii; Erickson et al. 2001, pp. 8, 11, 14, 15).
Noise is produced by wind turbine mechanical operation (gear boxes,
cooling fans) and airfoil interaction with the atmosphere. No published
studies have focused specifically on the noise effects of wind power to
Gunnison or greater sage-grouse. In studies conducted in oil and gas
fields, noise may have played a factor in habitat selection and
decrease in greater sage-grouse lek attendance (Holloran 2005, pp. 49,
56). However, comparison between wind turbine and oil and gas
operations is difficult based on the character of sound. Adjusting for
manufacturer type and atmospheric conditions, the audible operating
sound of a single wind turbine has been calculated as the same level as
conversational speech at 1 m (3 ft) at a distance of 600 m (2,000 ft)
from the turbine. This level is typical of background levels of a rural
environment (BLM 2005e, p. 5-24). However, commercial wind farms do not
have a single turbine, and multiple turbines over a large area would
likely have a much larger noise print. Low-frequency vibrations created
by rotating blades also produce annoyance responses in humans (Van den
Berg 2004, p. 1), but the specific effect on birds is not documented.
Moving blades of turbines cast moving shadows that cause a
flickering effect producing a phenomenon called ``shadow flicker''
(American Wind Energy Association (AWEA) 2008, p. 5-33). Shadow flicker
could mimic predator shadows and elicit an avoidance response in birds
during daylight hours, but this potential effect has not been
investigated. However, greater sage-grouse hens with broods have been
observed under turbines at Foote Creek Rim in south-central Wyoming
(Young 2004, pers. comm.), suggesting those birds were not disturbed by
the motion of turbine blades.
Wind Energy in the Monticello Population Area--
There is increasing interest in wind energy development in the
vicinity of the Monticello population in San Juan County, Utah (UDWR
2011, p. 3). Three wind energy projects are proposed in the vicinity of
Gunnison sage-grouse habitat (IEc 2014, p. 7-2). The San Juan County
Commission recently issued a permit for wind energy development on
private land in occupied habitat in the Monticello population area, and
development is currently underway there by Eco-Power Wind Farms, LLC
(IEc 2014, p. 7-2). Other landowners have recently been approached to
lease their properties for wind development as well (Messmer 2013, p.
14). The two other wind projects are proposed for areas outside of
occupied Gunnison sage-grouse habitat (IEc 2014, p. 7-2 to 7-3, and
references therein).
In addition, the State of Utah recently completed a statewide
screening study to identify geographic areas with a high potential for
renewable energy development (UDNR 2009, entire). An area approximately
80,200-ha (198,300-ac) in size northwest of the city of Monticello, UT,
was identified, with a high level of confidence, as a wind power
production zone with a high potential for utility-scale wind
development (production of greater than 500 megawatts) (UDNR 2009, p.
19). The mapped wind power production zone overlaps with nearly all
Gunnison sage-grouse occupied habitat in the Monticello population, as
well as the large area surrounding the perimeter of occupied habitat.
The Monticello population is currently small (approximately 70
individuals), with apparent low resilience (see discussion and analysis
in Factor E below), making it particularly sensitive to habitat loss
and other impacts. Therefore, we conclude that future wind energy
development poses a threat to the Monticello population of Gunnison
sage-grouse.
Wind Energy in All Other Population Areas--
We found no additional information on the presence of existing,
pending, or authorized wind energy sites, or any other areas with high
potential for wind energy development within any other Gunnison sage-
grouse population area.
Summary of Renewable Energy Development
Based on the above information, we do not consider renewable energy
development to be a current threat to Gunnison sage-grouse range-wide.
However, in the Gunnison Basin, geothermal development potential is
high; if geothermal energy development were to increase here in the
future, it may influence the overall long-term viability of the
Gunnison Basin population; thus, it is a potential future threat to
that population. Similarly, information suggests wind energy
development may increase in the future in the Monticello population,
potentially contributing to further population declines in this small
and vulnerable population. Therefore, wind
[[Page 69260]]
energy development is a future threat to the Monticello population of
Gunnison sage-grouse.
Pi[ntilde]on-Juniper Encroachment
Pi[ntilde]on-juniper woodlands are a native habitat type dominated
by pi[ntilde]on pine (Pinus edulis) and various juniper species
(Juniperus species) that can encroach upon, infill, and eventually
replace sagebrush habitat and other rangelands. Pi[ntilde]on-juniper
extent has increased ten-fold in the Intermountain West since Euro-
American settlement, causing the loss of many bunchgrass and sagebrush-
bunchgrass communities (Miller and Tausch 2001, pp. 15-16).
Pi[ntilde]on-juniper woodlands have also been expanding throughout
portions of the range of Gunnison sage-grouse (BLM 2009a, pp. 14, 17,
25), although we do not have information that quantifies this
expansion. Pi[ntilde]on-juniper expansion has been attributed to the
reduced influence of fire, the introduction of livestock grazing,
increases in global carbon dioxide concentrations, climate change, and
natural recovery from past disturbance (Miller and Rose 1999, pp. 555-
556; Miller and Tausch 2001, p. 15; Baker 2011, p. 199). In addition,
Gambel oak (Quercus gambelii) invasion as a result of fire suppression
is a potential threat to Gunnison sage-grouse (CDOW 2002, p.139) if
stands become thick and begin to choke out sagebrush understory.
However, some deciduous shrub communities (primarily Gambel oak and
serviceberry) are used seasonally by Gunnison sage-grouse (Young et al.
2000, p. 451).
Removal of pi[ntilde]on-juniper is a common treatment to improve
sage-grouse habitat. Similar to powerlines, trees provide perches for
raptors, and as a consequence, Gunnison sage-grouse avoid areas with
pi[ntilde]on-juniper (Commons et al. 1999, p. 239). In Oregon, greater
sage-grouse lek activity ceased when conifer canopy exceeded 4 percent
of the land area, suggesting that low levels of pi[ntilde]on-juniper
encroachment can lead to population-level impacts (Baruch-Mordo et al.
2013, p. 238). The number of male Gunnison sage-grouse observed on leks
in the Crawford population doubled after pi[ntilde]on-juniper removal
and mechanical treatment of mountain sagebrush and deciduous brush
(Commons et al. 1999, p. 238). However, removal of all trees in a given
area is likely not appropriate, based on the historical presence of
pi[ntilde]on-juniper communities when Gunnison sage-grouse were more
abundant and widespread. Pi[ntilde]on-juniper abundance likely
fluctuated over time in response to fire, at times occupying
approximately 20 percent of the sagebrush landscape (Baker 2013, p. 8).
Pi[ntilde]on-Juniper Encroachment in All Population Areas
The Gunnison Basin population area is not currently undergoing
significant pi[ntilde]on-juniper encroachment (Boyle and Reeder 2005,
Figure 4-1); however, all other populations have some degree of
documented encroachment. A considerable portion of the Pi[ntilde]on
Mesa population is experiencing pi[ntilde]on-juniper encroachment.
Approximately 9 percent (1,140 ha [3,484 ac]) of occupied habitat in
the Pi[ntilde]on Mesa population area has pi[ntilde]on-juniper
coverage, while 7 percent (4,414 ha [10,907 ac)] of vacant or unknown
(suitable habitat for sage-grouse that is separated from occupied
habitats that either (1) has not been adequately inventoried, or (2)
has not had documentation of grouse presence in the past 10 years
(GSRSC 2005, p. 258) and 13 percent (7,239 ha [17,888 ac]) of potential
habitat (unoccupied habitats suitable for occupation of sage-grouse if
practical restoration were applied) have encroachment (BLM 2009a, p.
17).
Some areas on lands managed by the BLM within other population
areas are undergoing pi[ntilde]on-juniper invasion. However, the extent
of the area affected has not been quantified (BLM 2009a, p. 74; BLM
2009a, p. 9). Approximately 9 percent of the 1,300 ha (3,200 ac) of the
current range in the Crawford population is dominated by pi[ntilde]on-
juniper (GSRSC 2005, p. 264). However, BLM (2005d, p. 8) estimated that
as much as 20 percent of the Crawford population area is occupied by
pi[ntilde]on-juniper, although much of that has been removed by habitat
treatments in recent years. Pi[ntilde]on and juniper trees have also
been encroaching in peripheral habitat on Sims Mesa, and to a lesser
extent on Cerro Summit, but not to the point where it is a threat to
the Cerro Summit-Cimarron-Sims Mesa population area (CDOW 2009b, p.
47). Pi[ntilde]on and juniper trees are reported to be encroaching
throughout the current range in the Monticello group, based on a
comparison of historical versus current aerial photos, but no
quantification or mapping of the encroachment has occurred (San Juan
County GSWG 2005, p. 20). A relatively recent invasion of pi[ntilde]on
and juniper trees between the Dove Creek and Monticello groups appears
to be contributing to their isolation from each other (GSRSC 2005, p.
276).
Within the range of Gunnison sage-grouse, approximately 5,341 ha
(13,197 ac) of pi[ntilde]on-juniper have been treated with various
methods designed to remove pi[ntilde]on and juniper trees since 2005,
and nearly half of which occurred in the Pi[ntilde]on Mesa population
area (CDOW 2009b, pp. 111-113). Mechanical treatment of areas
experiencing pi[ntilde]on-juniper encroachment continues to be one of
the most successful and economical treatments for the benefit of
Gunnison sage-grouse habitat. However, such treatments may have minimal
benefit at the population level, since the majority of affected
populations have continued to decline since 1996 (Figure 3) despite
considerable efforts to remove pi[ntilde]on-juniper in those areas.
Summary of Pi[ntilde]on-Juniper Encroachment
Most Gunnison sage-grouse population areas are experiencing low to
moderate levels of pi[ntilde]on-juniper encroachment; however,
considerable pi[ntilde]on-juniper encroachment in the Pi[ntilde]on Mesa
population has occurred. The encroachment of pi[ntilde]on-juniper into
sagebrush habitats can contribute to the decline of Gunnison sage-
grouse habitat. However, pi[ntilde]on-juniper treatments, particularly
when completed in the early stages of encroachment when the sagebrush
and forb understory is still intact, have the potential to benefit
sage-grouse (Commons et al. 1999, p. 238). Approximately 5,341 ha
(13,197 ac) within the range of Gunnison sage-grouse has been treated
to address pi[ntilde]on-juniper encroachment. Based on the rate of past
treatment efforts (CDOW 2009c, entire), we expect pi[ntilde]on-juniper
encroachment and corresponding treatment efforts to continue.
Pi[ntilde]on-juniper encroachment is contributing to habitat decline in
a limited area, but the level of encroachment is not sufficient to pose
a threat to Gunnison sage-grouse at a population or rangewide level at
this time. However, in combination with other factors such as those
contributing to habitat decline (roads, powerlines, invasive plants,
etc.), pi[ntilde]on-juniper encroachment poses a threat to the species.
In addition, future conditions due to drought or climate change may
intensify the problem such that pi[ntilde]on-juniper encroachment
becomes a more serious threat, particularly in the smaller, declining
populations.
Conversion to Agriculture
While sage-grouse may forage on agricultural croplands (Commons
1997, pp. 28-35), they tend to avoid landscapes dominated by
agriculture (Aldridge et al. 2008, p. 991) and do not nest or winter in
agricultural lands where shrub cover is lacking. Effects resulting from
agricultural activities extend into adjoining sagebrush, and
[[Page 69261]]
include increased predation and reduced nest success due to predators
associated with agriculture (Connelly et al. 2004, p. 7-23).
Agricultural lands provide limited benefits for sage-grouse as some
crops such as alfalfa (Medicago sativa), winter wheat (Triticum
aestivum), and pinto bean sprouts (Phaseolus spp.) are eaten or used
seasonally for cover by Gunnison sage-grouse (Braun 1998, pers. comm.,
Lupis et al. 2006, entire). Since lek monitoring began, the Monticello
population of Gunnison sage-grouse appears to have been at its highest
numbers during the 1970's and 1980's (SJCWG 2003, p. 5). During this
time, winter wheat and dryland alfalfa were the primary agricultural
crops in the area, and many growers did not use herbicides or
insecticides because of the slim profit margin in growing these crops.
Also during this period, landowners frequently reported observing
flocks of sage-grouse in their fields during harvest and post-harvest
periods (Messmer 2013, p. 19). These agricultural fields and their
management may have provided a surplus of arthropods and forbs for
Gunnison sage-grouse, and for hens with broods, in particular. Despite
these seasonal benefits, crop monocultures do not provide adequate
year-round food or cover (GSRSC 2005, pp. 22-30).
Current Agriculture in All Gunnison Sage-grouse Population Areas
The following estimates of land area dedicated to agriculture
(including grass/forb pasture) were derived primarily from Southwest
Regional Gap Analysis Project (SWReGAP) landcover data (USGS 2004,
entire). Agricultural parcels are distributed patchily amongst what was
recently a sagebrush landscape. These agricultural parcels are likely
used briefly by grouse to move between higher quality habitat patches.
Habitat conversion to agriculture is most prevalent in the Monticello-
Dove Creek population area, where approximately half of Gunnison sage-
grouse occupied range is currently in agricultural production
(primarily cropland and pastureland). The conversion of sagebrush to
agricultural use eliminated suitable vegetation cover at three leks in
the Monticello population, and those leks are no longer used by
Gunnison sage-grouse (SJCWG 2000, p. 15; GBSC 2005, p. 81). However,
habitat loss due to agricultural conversion has been mitigated somewhat
by the Conservation Reserve Program (CRP) (see section below, NRCS and
Private Land Conservation Efforts, in this Factor A analysis).
In the Gunnison Basin, approximately 9 percent of the occupied
range is currently in agricultural production. In Gunnison County,
approximately 38,419 ha (94,936 ac) is currently in agricultural
production (primarily irrigated hay and pastureland) (Gunnison County
2013a, p. 97, 123; GSRSC 2005, p. 73), though we do not know what
proportion of these lands occur in occupied range. Approximately 15
percent of the occupied range in the San Miguel Basin is currently in
agricultural production. In the Cerro Summit-Cimarron-Sims Mesa
population, approximately 14 percent of the occupied range is currently
in agricultural production. Habitat conversion due to agricultural
activities is limited in the Crawford, Pi[ntilde]on Mesa, and Poncha
Pass populations, with 3 percent or less of the occupied range
currently in agricultural production in each of the population areas.
Substantial portions of sage-grouse habitat on private land in the
Gunnison Basin, Crawford, San Miguel, and Pi[ntilde]on Mesa population
areas are currently enrolled in the CCAA (see Conservation Programs and
Efforts Related to Habitat Conservation in this Factor A analysis).
Except for properties recently enrolled in the program, all enrolled
private lands have been monitored using standardized vegetation
transects and rangeland health assessments and, despite recent drought
conditions and ongoing land uses, no significant deviations from
baseline habitat conditions were observed. CPW reports that all
enrolled properties continue to be in compliance with the terms of
their Certificates of Inclusion (CIs) (CPW 2014a, p. 1). This
information suggests that the current level of livestock grazing and
operations on those lands is compatible with Gunnison sage-grouse
habitat needs.
Except in Gunnison County, where cropland is relatively limited,
total cropland has declined over the past two decades in all counties
within the occupied range of Gunnison sage-grouse (USDA NASS 2010,
entire). The majority of agricultural land use in Gunnison County is
hay production, and this has also declined over the past two decades
(USDA NASS 2010, p. 1). We do not have any information to predict
changes in the amount of land devoted to agricultural purposes.
However, because of this long-term downward trend in land area devoted
to agriculture, we do not expect a significant amount of Gunnison sage-
grouse habitat to be converted to agricultural purposes in the future.
Summary of Conversion to Agriculture
Throughout the range of Gunnison sage-grouse, the amount of land
area devoted to agriculture is declining. Therefore, although we expect
most land currently in agricultural production to remain so
indefinitely, we do not expect significant additional, future habitat
conversion to agriculture within the range of Gunnison sage-grouse. The
loss of sagebrush habitat from 1958 to 1993 was estimated to be
approximately 20 percent throughout the range of Gunnison sage-grouse
(Oyler-McCance et al. 2001, p. 326). One exception is the Monticello-
Dove Creek population, where more than half of the occupied range is
currently in agriculture or other land uses that are generally
incompatible with Gunnison sage-grouse conservation. This habitat loss
is being mitigated somewhat by the enrollment of lands in CRP. Because
of its limited extent, we do not consider future conversion of
sagebrush habitats to agriculture to be a current or future threat to
the persistence of Gunnison sage-grouse.
However, the extent of historical conversion of sagebrush to
agriculture has fragmented the remaining Gunnison sage-grouse habitat
to a degree that currently occupied lands are inadequate for the
species' conservation, especially in light of other threats discussed
throughout this rule. As described above in the introduction to this
Factor A analysis, the onset of Euro-American settlement in the 1800s
resulted in significant human alterations to sagebrush ecosystems
throughout North America, primarily as a result of urbanization,
agricultural conversion, and irrigation projects (West and Young 2000,
pp. 263-265; Miller et al. 2011, p. 147). Areas in Colorado that
supported basin big sagebrush were among the first sagebrush community
types converted to agriculture because their soils and topography are
well-suited for agriculture (Rogers 1964, p. 13). Decreases in the
abundance of sage-grouse paralleled the loss of range (Braun 1998, pp.
2-3), and a gradual but marked decrease in sage-grouse distribution and
numbers in Colorado had begun around 1910 (Rogers 1964, pp. 20-22).
However, due to the long-term downward trend in land area devoted to
agriculture, we do not expect agricultural conversion to be a
significant cause of further range contraction into the future.
Large-Scale Water Development and Irrigation
Irrigation projects have generally resulted in loss of sage-grouse
habitat
[[Page 69262]]
(Braun 1998, p. 6). Development of Blue Mesa Reservoir in 1965 in the
Gunnison Basin flooded an estimated 3,700 ha (9,200 ac), or 1.5 percent
of potential habitat for Gunnison sage-grouse (McCall 2005, pers.
comm.), and according to Gunnison County (2013a, p. 124), at least one
known lek. Based on the size and location of Blue Mesa Reservoir, we
presume that habitat connectivity and dispersal of birds between the
Gunnison Basin population and satellite populations to the west were
impacted. Three other reservoirs inundated approximately 2 percent of
habitat in the San Miguel Basin population area (Garner 2005, pers.
comm.).
The demand for water in Gunnison sage-grouse range is expected to
increase into the future due to increased temperatures resulting from
climate change (see Climate Change in this Factor A analysis), severe
drought (see Drought and Extreme Weather in the Factor E analysis), and
human population growth (see Residential Development in this Factor A
analysis). Water demand from the Upper Colorado River Basin, which
encompasses Gunnison sage-grouse occupied range, is expected to
increase over the next several decades, and there are likely to be
significant shortfalls between projected water supply and demand
through 2060 (BOR 2013, entire). However, it is unknown if, when, or
where future water projects in the Upper Colorado River Basin would
occur.
A small amount of Gunnison sage-grouse habitat has been lost to
large-scale water development projects, but in potentially important
areas (see discussion above). We expect these existing reservoirs to be
maintained indefinitely, thus acting as another source of habitat
fragmentation. With increased water demand in the future, we expect
that water developments and irrigation practices may further contribute
to impacts on Gunnison sage-grouse, though the scope and magnitude of
those effects are unknown. Based on this information, we conclude that
large-scale water developments and irrigation are a threat of low
magnitude to Gunnison sage-grouse rangewide, both now and in the
future. Small-scale water developments, such as stock ponds and tanks,
are described and evaluated in the Domestic Grazing and Wildlife
Herbivory (Factor A analysis), and Disease (Factor C analysis) sections
of this rule.
Conservation Programs and Efforts Related to Habitat Conservation
Consideration of Conservation Efforts in This Rulemaking
Multiple partners including private citizens, nongovernmental
organizations, Tribal, State, and Federal agencies are engaged in
conservation efforts across the range of Gunnison sage-grouse. Numerous
conservation actions have already been implemented for Gunnison sage-
grouse, and these efforts have provided and will continue to provide
conservation benefit to the species. These implemented efforts are
considered below.
Additionally, there are recent and planned conservation efforts
that are intended to provide conservation benefits to the Gunnison
sage-grouse; some of which have not been fully implemented or shown to
be effective. The Service's Policy for Evaluation of Conservation
Efforts When Making Listing Decisions (PECE; 68 FR 15100, March 28,
2003) describes our procedure for evaluating the certainty of
implementation and effectiveness of these recent and future actions.
The purpose of PECE is to ensure consistent and adequate evaluation of
recently formalized conservation efforts when making listing decisions.
The policy provides guidance on how to evaluate formalized conservation
efforts that have not yet been implemented or have not yet demonstrated
effectiveness. The evaluation focuses on the certainty that the
conservation efforts will be implemented and effectiveness of the
conservation efforts. The policy defines ``formalized conservation
efforts'' as ``specific actions, activities, or programs designed to
eliminate or reduce threats or otherwise improve the status of
species'' that are identified in a conservation agreement, conservation
plan or similar document, and presents nine criteria for evaluating the
certainty of implementation and six criteria for evaluating the
certainty of effectiveness of such conservation efforts. These criteria
are not considered comprehensive evaluation criteria. The certainty of
implementation and the effectiveness of a formalized conservation
effort may also depend on species-specific, habitat-specific, location-
specific, and effort-specific factors.
Conservation efforts that are not sufficiently certain to be
implemented and effective cannot contribute to a determination that
listing is unnecessary or a determination that to list as threatened
rather than endangered (PECE, 68 FR 15115). Accordingly, before
considering whether a future formalized conservation effort contributes
to forming a basis for not listing a species, or listing a species as
threatened rather than endangered, we must find that the conservation
effort is sufficiently certain to be implemented, and effective, so as
to have contributed to the elimination or adequate reduction of one or
more threats to the species identified through the section 4(a)(1)
(five-factor) analysis. If a conservation effort meets the criteria
described in PECE, we are able to include and rely upon these recent
and future efforts in our current threats analysis and status
determination.
We completed an evaluation of the recently developed multi-county
Conservation Agreement and Memorandum of Understanding (MOU), the 2013
Gunnison Basin CCA and the Ute Mountain Ute Tribe's 2014 Species
Management Plan pursuant to PECE; however, only the CCA met the
criteria established under PECE and thus may be considered in
determining whether the species is warranted for listing or is
threatened rather than endangered. Neither the MOU nor the multi-county
conservation agreement can contribute to these determinations because
they do not include specific conservation efforts as defined in the
PECE polic, and the Tribal plan only met 7 of the 15 PECE criteria.
Therefore, we did not rely upon these conservation efforts in our
current threats analysis and status determination.
The 2006 Colorado Gunnison sage-grouse CCAA, 2013 Gunnison Basin
CCA, habitat improvement projects, and other non-regulatory
conservation efforts that address habitat-related issues are described
and evaluated below in this section. Habitat-related and other
conservation efforts provided through Federal, state, tribal, and local
laws and regulations, conservation easements, and similar regulatory
mechanisms are evaluated under Factor D below. Also, throughout this
rule, conservation efforts are described under relevant threat
sections.
2006 Colorado Candidate Conservation Agreement with Assurances (CCAA)
In April 2005, the Colorado Division of Wildlife (CDOW, now called
Colorado Parks and Wildlife (CPW)) applied to the Service for an
Enhancement of Survival Permit for the Gunnison sage-grouse pursuant to
section 10(a)(1)(A) of the Act. The permit application included a
proposed Candidate Conservation Agreement with Assurances (CCAA)
between CPW and the Service. The standard that a CCAA must meet is that
the ``benefits of the conservation measures implemented by
[[Page 69263]]
a property owner under a CCAA, when combined with those benefits that
would be achieved if it is assumed that conservation measures were also
to be implemented on other necessary properties, would preclude or
remove any need to list the species'' (64 FR 32726, June 17, 1999). The
draft CCAA, the permit application, and the draft environmental
assessment were made available for public comment on July 6, 2005 (70
FR 38977). The CCAA and environmental assessment were finalized in
October 2006, and the associated permit was issued on October 23, 2006,
with a term of 20 years.
The goal of the CCAA is to reduce threats to Gunnison sage-grouse
and help provide for secure, self-sustaining local populations by
enrolling, protecting, maintaining, and enhancing or restoring non-
federally owned Colorado habitats of Gunnison sage-grouse (as described
further below). Landowners with eligible property in southwestern
Colorado could voluntarily sign up under the CCAA and associated permit
through a Certificate of Inclusion (CI) that specifies the land
enrolled in the CCAA and the habitat protection or enhancement measures
the landowner will implement on these lands. Eligible lands include
non-Federal lands in Colorado within the current range of Gunnison
sage-grouse where occupied, vacant/unknown, or potentially suitable
habitats occur, as mapped and identified in the RCP. After Gunnison
sage-grouse is listed under the Act, the CCAA remains in place and the
permit becomes effective. The permit exempts take of Gunnison sage-
grouse incidental to otherwise lawful activities specified in the CCAA
(e.g., crop cultivation or harvesting, livestock grazing, farm
equipment operation, commercial/residential development), when
performed in accordance with the terms of the CCAA, provided the
participating landowner is implementing conservation measures
voluntarily agreed to in the landowner's CI (USFWS 2006, entire).
Landowners may only enroll properties in the CCAA and receive these
benefits before a species is listed under the Act.
CPW may terminate landowner participation in the CCAA or otherwise
revoke the CI if the landowner fails to comply with or implement the
terms of the agreement. Further, the Service may suspend or revoke the
permit for just cause or if continuation of permitted activities would
likely result in jeopardy to Gunnison sage-grouse (USFWS 2006, p. 20).
However, except for recently enrolled properties, all properties have
been monitored using standardized vegetation transects and rangeland
health assessments and, despite recent drought conditions and ongoing
land uses, no significant deviations from baseline habitat conditions
have been observed. According to CPW, which is responsible for
administering the CCAA with Service oversight, all enrolled properties
continue to be in compliance with the terms of their CIs (CPW 2014a, p.
1).
Colorado Parks and Wildlife has made great strides to enroll
landowners, protect habitat, and alleviate threats to Gunnison sage-
grouse under this voluntary program. We estimate that by December 2014,
when this rule becomes effective, 40 CIs will have been completed for
private properties, enrolling 94,391 ac, roughly 81,156 ac that are in
suitable habitat, in four Gunnison sage-grouse populations. This
includes 32 CIs (54,580 ac (roughly 50,410 ac in suitable habitat)) in
the Gunnison Basin; 2 CIs (4,231 ac (roughly 3,921 ac in suitable
habitat)) in Crawford; 3 CIs (16,820 ac (roughly 13,694 ac in suitable
habitat)) in San Miguel; and 3 CIs (18,761 ac (roughly 13,131 ac in
suitable habitat)) in Pi[ntilde]on Mesa (Table 9).
Table 9--Completed and In-Progress CIs Under the Gunnison Sage-Grouse
CCAA
[CPW 2014a, entire; CPW 2014g, appendix 3]
------------------------------------------------------------------------
Total
----------------------------------------
Population Acres * in
# Enrolled acres suitable
habitat
------------------------------------------------------------------------
Gunnison Basin................. 32 54,580 50,410
Crawford....................... 2 4,231 3,921
San Miguel..................... 3 16,820 13,694
Pi[ntilde]on Mesa.............. 3 18,761 13,131
----------------------------------------
Rangewide Totals........... 40 94,391 81,156
------------------------------------------------------------------------
* These are estimates based on Geospatial analyses.
Based on the RCP conservation objective of securing and maintaining
90 percent of seasonally important habitat for the Gunnison sage-grouse
in each population area (GSRSC 2005, pp. 223-224), the CCAA identifies
targets for private land protection for each population area, including
private lands not already considered as protected under a conservation
easement (USFWS 2006, pp. 11-12). However, we note that there are lands
that are part of the CCAA, and are also protected under a conservation
easement. Targeted CCAA acreages on private lands are intended to
complement lands already receiving some protection because they are
under Federal ownership.
A habitat protection objective of 75 percent of seasonally
important habitat was identified for the Cerro Summit-Cimarron-Sims
Mesa population, because this area is thought to function more as a
habitat linkage between the San Miguel Basin, Gunnison, and Crawford
populations (GSRSC 2005, pp. 223-224; USFWS 2006, p. 10). The CCAA
habitat protection target for the Gunnison Basin population was based
on important seasonal habitats since these are mapped in this area. In
the remaining populations where important seasonal habitats are not
mapped, CCAA targets were based on available occupied habitat (USFWS
2006, pp. 11-12). Roughly 99 percent of the Gunnison Basin population
area target, 95 percent of the Crawford population area target, 45
percent of the San Miguel population area target, and 217 percent of
the Pi[ntilde]on Mesa population area target on private lands are
enrolled in the CCAA (Table 10).
[[Page 69264]]
Table 10--CCAA Habitat Protection Targets on Private Land and Enrollment
[CPW 2014a, entire; CPW 2014b, entire]
----------------------------------------------------------------------------------------------------------------
CCAA Target Enrolled CIs % of CCAA
Population (ac) on (ac) \a\ on target on
private land private land private land
----------------------------------------------------------------------------------------------------------------
Gunnison basin.................................................. 55,302 54,580 99
Crawford........................................................ 4,143 4,231 95
San Miguel...................................................... 37,690 16,820 45
Pi[ntilde]on Mesa............................................... 8,635 18,761 217
----------------------------------------------------------------------------------------------------------------
\a\ CI acreage in suitable habitat based on geospatial analyses. Includes some properties also protected by
conservation easements.
The CCAA promotes the conservation of Gunnison sage-grouse on
portions of private lands in the Gunnison Basin, Crawford, San Miguel,
and Pi[ntilde]on Mesa populations. In these areas, threats to Gunnison
sage-grouse are reduced and habitats covered by the CCAA are protected,
maintained, enhanced, or restored. In particular, private land uses
including livestock grazing and agricultural production are managed to
be consistent with the needs of Gunnison sage-grouse and the species'
conservation. Although enrollment of property in the CCAA is voluntary
and not permanent or binding, the program's regulatory assurances and
take authority provide an incentive for participating landowners to
continue enrollment and compliance with terms of their CI. However,
there are instances in which those assurances and incentives would no
longer be desirable to the landowner. For instance, a landowner may
choose to opt out of the CCAA to sell subject lands, whether for
development or other purposes, meaning the benefits to Gunnison sage-
grouse provided under the program would cease as well unless the new
owner decided to continue the property's enrollment in the CCAA. Thus,
although residential development is expected to be very limited on
enrolled properties under the terms of the CIs (USFWS 2006, p. 13), the
CCAA does not preclude the sale of those properties nor their
subsequent development. Such development would likely result in further
habitat loss and decline for Gunnison sage-grouse, though we cannot
predict the scope or magnitude of those impacts. Therefore, the Service
views the CCAA differently from conservation easements in terms of its
regulatory certainty (see Other Regulatory Mechanisms: Conservation
Easements, Factor D analysis; and Residential Development, in this
Factor A analysis). Nevertheless, we consider lands enrolled under the
CCAA to be a net gain for Gunnison sage-grouse conservation,
particularly in regard to the reduction of habitat-related impacts due
to ongoing land uses on private lands.
2013 Gunnison Basin Candidate Conservation Agreement
Candidate Conservation Agreements are formal, voluntary agreements
between the Service and one or more parties to address the conservation
needs of one or more candidate species or species likely to become
candidates in the near future. Participants commit to implement
specific actions designed to remove or reduce threats to the covered
species, so that listing may not be necessary. Unlike CCAAs, CCAs do
not provide assurances that additional conservation measures will not
be required if a species is listed or critical habitat is designated.
In January 2010, the BLM, USFS, NPS, and other members of the
Gunnison Basin Sage-Grouse Strategic Committee (Strategic Committee)
began preparing a Candidate Conservation Agreement (CCA) with the
Service to promote the conservation of the Gunnison Basin population of
Gunnison sage-grouse (BLM 2013b, entire). The CCA was completed and
signed by the Federal land management agencies on August 23, 2012. On
April 12, 2013, the Federal land management agencies submitted a joint
biological assessment (BA) and letter to the Service requesting an ESA
Section 7 formal conference on the CCA. The Service issued its
conference opinion on July 29, 2013 (USFWS 2013b, entire) and
subsequently signed the CCA. The conference opinion evaluated
anticipated effects of the CCA on Gunnison sage-grouse and estimated
incidental take over a 20-year period, or through July 29, 2033.
The CCA serves as a project screen and requires implementation of
conservation measures associated with specified actions under three
Federal land use programs: Development (roads, transmission lines,
etc.), recreation (such as trails and special recreation permits,
etc.), and livestock grazing (permit renewals and operations). Larger
or impact intensive projects (e.g., construction of a new transmission
line, energy development) are not covered under the CCA, and any
conservation measures required for these projects on Federal lands in
the Gunnison Basin will be addressed separately through ESA section 7
consultation. However, the actions addressed by the CCA, as listed
above, comprise the most common land use authorizations where Gunnison
sage-grouse occur on Federal lands in the Gunnison Basin. The CCA and
conference opinion cover an estimated 160,769 ha (397,267 ac) of
occupied habitat on Federal lands in the Gunnison Basin. This
constitutes about 67 percent of the estimated 239,953 ha (592,936 ac)
of total occupied habitat in the Gunnison Basin; approximately 78
percent of rangewide occupied habitat on Federal lands; and
approximately 42 percent of rangewide total occupied habitat for the
species.
Conservation measures in the CCA and conference opinion are actions
that the signatory agencies agreed to implement to further the recovery
of Gunnison sage-grouse. A key component of the CCA's site-specific
conservation measures is a requirement for offsetting habitat loss or
disturbance to ensure a net increase in priority habitats, and no net
loss (maintenance) of secondary habitats for Gunnison sage-grouse. A
number of other conservation measures and practices will be implemented
pursuant to the CCA by the Federal agencies during the ESA section 7
consultation process to avoid and minimize project impacts on Gunnison
sage-grouse.
The Service commends the Federal agencies, and the Gunnison Basin
Sage-grouse Strategic Committee for their efforts in the design of the
CCA and implementation of conservation measures to benefit Gunnison
sage-grouse. In our conference opinion, we found that, despite
incidental negative effects on individual birds and potential short-
term, localized, and unavoidable effects, implementation of the CCA
will provide a long-term, net benefit for Gunnison sage-grouse on a
landscape scale. The conservation measures and mitigation scheme are
required for the signatory Federal agencies engaging in covered
activities, and are based on
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current applicable land management plans of the respective agencies. As
noted earlier, approximately 87 percent of the rangewide population of
Gunnison sage-grouse occurs in the Gunnison Basin population.
Implementation of the proposed action and its conservation measures
will help reduce several substantial threats known to affect the
species on Federal lands in the Gunnison Basin, including habitat
decline. Although we analyzed the CCA under our PECE policy and found
it satisfies all the criteria for consideration in our listing
determination, approximately 22 percent of rangewide occupied habitat
on Federal lands--all within the satellite population areas--are not
covered under the CCA or a similar agreement. Additional protections on
those Federal lands will be necessary to conserve these smaller,
declining populations. Therefore, while the CCA is effective in
reducing some threats in the Gunnison Basin population, it is not
effective at reducing the threats to the species rangewide such that
listing is not warranted.
NRCS and Private Lands Conservation Efforts
The NRCS's Sage-Grouse Initiative (SGI) is a rangewide,
collaborative, targeted effort to implement conservation practices
which alleviate threats that some agricultural activities can pose to
greater and Gunnison sage-grouse while improving the sustainability of
working ranches. Through SGI, the NRCS and its partners help ranchers
proactively conserve and improve sage-grouse habitat. The SGI includes
a monitoring and evaluation component for projects to measure the
response of sage-grouse populations and vital rates (USFWS 2010d, p.
5).
In 2010, the Service issued the SGI Conference Report (USFWS 2010d,
entire) to facilitate the SGI and conservation of Gunnison and greater
sage-grouse rangewide. In the Conference Report, the Service provided
guidance and conservation recommendations for avoiding and minimizing
adverse effects to sage-grouse associated with the SGI, and found that
the implementation of the SGI and identified conservation measures
would have a net benefit on the species. The report identified primary
conservation practices (management, vegetative, and structural)
implemented by the NRCS to benefit sage-grouse and its habitat, and
specific conservation measures (e.g., avoiding fence construction near
leks) for those practices. The report did not provide for exemption of
incidental take of sage-grouse if either species is listed under the
Act (USFWS 2010d, entire).
Also under the SGI and related private land programs (e.g., Farm
Bill), the NRCS, Farm Service Agency (FSA), U.S. Fish and Wildlife
Service Partners for Fish and Wildlife (PFW), CPW, and other partners
have implemented numerous habitat improvement projects on private lands
to benefit Gunnison sage-grouse. Since 1998, the Service's Colorado PFW
has completed 20 habitat improvement or restoration projects in
Gunnison sage-grouse habitat including projects on 638.5 ac of wetland
habitat; 3,957 ac of upland habitat; and 4.3 mi of riparian habitat in
Gunnison, Saguache, and Montrose Counties, with most treated acres in
Gunnison County. Project types included restoration, improvement, and
management actions such as enhancement of wetland and brood-rearing
habitat, treating sagebrush, reseeding of native vegetation, fencing
installation, grazing management, and removal of pi[ntilde]on-juniper
(USFWS 2014c, entire). Contributing partners for these projects have
included CPW, NRCS, and Rocky Mountain Bird Observatory. In addition,
in 2006 the NRCS Gunnison Basin Conservation District sponsored a Range
Management School to assist ranchers in managing and monitoring their
lands to benefit Gunnison sage-grouse and meet the requirements of the
CCAA (Gunnison County 2013a, pp. 204-206).
Projects undertaken through SGI and related private land programs,
as described above, have benefitted Gunnison sage-grouse and its
habitat, but are limited in extent. Therefore, it is unlikely that such
actions are able to offset habitat loss and decline across the species'
range.
The CRP is another Federally sponsored program that has helped
offset the loss of Gunnison sage-grouse habitat. Administered by the
FSA, this program provides incentives to landowners to plant more
natural vegetation in lands formerly devoted to agricultural
production. The NRCS provides technical assistance and planning in the
implementation of CRP. The CRP helps address the threat of habitat
decline due to agricultural conversion.
Lands within the occupied range of Gunnison sage-grouse currently
enrolled in the CRP are limited to Dolores and San Miguel counties in
Colorado, and San Juan County in Utah (USDA FSA 2010, entire). From
2000 to 2008, CRP enrollment averaged 10,622 ha (26,247 ac) in Dolores
County, 1,350 ha (3,337 ac) in San Miguel County, and 14,698 ha (36,320
ac) in San Juan County (USDA FSA 2010, entire). In 2011, approximately
9,793 ha (24,200 ac) were enrolled in the CRP program within occupied
habitat in the Monticello population (UDWR 2011, p. 7). This area
represents approximately 34 percent of the occupied habitat in the
Monticello population, and approximately 22 percent of the entire
Monticello-Dove Creek population area. By 2011, lands that had dropped
out of the CRP program were replaced by newly enrolled properties, and
the total acreage of lands enrolled in the CRP program remained at the
maximum allowed by the FSA for San Juan County, UT (UDWR 2011, p. 7).
Gunnison sage-grouse are known to regularly use CRP lands in the
Monticello population (Lupis et al. 2006, pp. 959-960; Ward 2007, p.
15). In San Juan County, Gunnison sage-grouse use CRP lands in
proportion to their availability (Lupis et al. 2006, p. 959). The CRP
areas are used by grouse primarily as foraging and brood-rearing
habitat, but these areas vary greatly in plant diversity and forb
abundance, generally lack any shrub cover (Lupis et al. 2006, pp. 959-
960; Prather 2010, p. 32), and thus are less suitable for nesting and
wintering habitat.
Except in emergency situations such as drought, CRP-enrolled lands
are not hayed or grazed. In response to a severe drought, four CRP
parcels totaling 1,487 ha (3,674 ac) in San Juan County, UT, were
emergency grazed for a duration of one to two months in the summer of
2002 (Lupis et al. 2006, p. 959). Males and broodless females avoided
the grazed areas while cattle were present but returned after cattle
were removed (Lupis et al. 2006, pp. 960-961). Thus, the effects from
grazing were likely negative but apparently short in duration.
Largely as a result of agricultural conversion, sagebrush patches
in the Monticello-Dove Creek subpopulation area have progressively
become smaller and more fragmented, thereby limiting the amount of high
quality nesting and winter habitat (GSRSC 2005, pp. 82, 276). Overall,
the CRP has provided important foraging habitat and has protected a
portion of the Monticello-Dove Creek population from more intensive
agricultural use and development. Continued enrollment of lands in CRP
and management of those lands are conservation priorities of the local
sage-grouse working group (SJCWG 2003, entire). However, the overall
value of CRP lands to Gunnison sage-grouse to reduce or remove the
threat of habitat loss and fragmentation is currently limited because
these lands largely lack sagebrush cover required by the species
throughout most of the year.
[[Page 69266]]
The value of CRP lands to the species will likely increase over time
with the establishment of sagebrush in those areas. The extent to which
existing CRP lands will be reenrolled in the future is unknown.
However, given the recent enrollment, we expect lands to continue to be
enrolled into the future.
Tribal Species Management Plan
Approximately 12,000 ac of occupied habitat on Pinecrest Ranch are
owned by the Ute Mountain Ute Tribe (Tribe) under restricted fee
status. The Pinecrest Ranch includes a total of 18,749 ac in the
Gunnison Basin population area west of Gunnison, Colorado. The Tribe
uses the ranch primarily for livestock grazing and for important
traditional and cultural purposes. In February 2014, the Tribe
completed a Species Management Plan (SMP) to promote the conservation
of Gunnison sage-grouse and its habitat on the Pinecrest Ranch while
maintaining a sustainable agricultural operation and other traditional
uses of the property (Ute Mountain Ute Tribe 2014a, entire). On April
9, 2014, the Tribe approved and adopted the SMP for the Pinecrest Ranch
per Resolution No. 2014-059 (Ute Mountain Ute Tribe 2014b, pp. 1-2).
The SMP includes management actions and/or considerations that will
benefit Gunnison sage-grouse including, but not limited to, continued
predator control, seasonal restrictions for construction and
development activities, road restrictions and closures, wildlife-
friendly fencing, outreach and education, and sustainable grazing
practices which are compatible with maintaining habitat that meets the
species' needs (UMUT 2014, pp. 7-15). While we think the SMP provides a
benefit to species, we evaluated the species management plan under our
PECE policy, but found the plan met only 7 of the 15 criteria.
Other Conservation Efforts
To varying degrees, most counties in Colorado either support or are
involved in other conservation efforts for Gunnison sage-grouse, such
as local working groups, habitat improvement projects, and research
projects (Gunnison County 2013b, Appendix 1 A-K, CPW 2014g, Attachment
3 and Appendix A; Office of the Governor of Colorado 2014, entire).
Through CPW, the State of Colorado has also been a leader in sage-
grouse research and conservation efforts throughout the species' range
(CPW 2014g, entire; Office of the Governor of Colorado 2014, entire).
We have considered all such conservation efforts in this listing
determination, and highlight some of the more significant of these
efforts below.
Except for the Cerro Summit-Cimarron-Sims Mesa population, each of
the Gunnison sage-grouse population areas has a Conservation Plan
authored by Local Working Groups with publication dates of 1997 to 2011
(CSGWG 1997; Dove Creek/Monticello Local Working Group 1998; GSRSC
2005; Pi[ntilde]on Mesa Gunnison Sage-grouse Working Group 2000; Poncha
Pass Local Working Group 2000; Gunnison Sage-grouse Working Group 2000;
SJCWG 2000 and 2003; SMBGSWG 2009; Crawford Area Sage-grouse Working
Group 2011). These plans provide guidance and recommendations for
management of Gunnison sage-grouse and have been the basis for
identifying and prioritizing local conservation efforts. We have
reviewed all of the Local Working Group plans and the implementation
reporting we received with respect to these plans. While these plans
are providing a conservation benefit to the species, the actions in
these plans are all voluntary and many of the satellite populations are
in a downward trajectory, therefore the actions do not reduce the
threats, such as residential development (Factor A), which may require
compensatory mitigation to ameliorate, and, to the species to a point
where listing is not warranted.
The Gunnison Sage-Grouse Rangewide Conservation Plan (RCP) was
developed by the states of Colorado and Utah and 5 Federal agencies,
including the Service, in 2005 to supplement the local working group
plans and to offer a rangewide perspective for conservation of the
species. The RCP includes specific, recommended avoidance and
minimization measures, as well as species and habitat conservation
targets. However, similar to the local plans, the RCP is a guidance
document only, is voluntary, and does not provide regulatory mechanisms
for Gunnison sage-grouse conservation (GSRSC 2005, p. 1). Where RCP
recommended conservation measures have been implemented, we have
evaluated and included them in our analysis. For example, the RCP
recommends road closures and the enactment of county regulations to
minimize impacts to the species; where appropriate, the existing
efforts that implement these recommendations are included in our
analysis. Overall, however, there is no requirement to implement the
recommendations in the RCP and past implementation of these
recommendations has generally been ad hoc and opportunistic. Given this
history, we find that the RCP is not effective at reducing the threats
acting on the species to the point where listing the species is not
warranted.
Other conservation efforts in the species' range include the North
Rim Landscape Strategy developed by Federal and state agencies,
partners, and stakeholders to supplement the Crawford Area Conservation
Plan. The strategy identifies broad recommendations for resource
management and conservation of Gunnison sage-grouse in the Crawford
population area, but is not a legal decision document (BLM 2013c, p. 4-
5).
Gunnison County has been particularly active in Gunnison sage-
grouse conservation activities. In 2005, it hired a Gunnison Sage-
grouse Coordinator and organized a Strategic Committee to facilitate
implementation of conservation measures in the Gunnison Basin under
both the local Conservation Plan (CSGWG 1997, entire) and RCP (GSRSC
2005, entire). An estimated $30 million has been invested in
conservation actions by these groups and partners in the Gunnison Basin
(Gunnison County 2013a, p. 147). Gunnison County reports that it alone
has contributed more than $1 million to Gunnison sage-grouse
conservation (Gunnison County 2013a, p. 218). In 2009, Gunnison County
adopted the Gunnison Basin Sage-grouse Strategic Plan (Gunnison County
2013a, Appendix E) to foster coordination and guide local citizens in
the conservation of Gunnison sage-grouse. Also in 2009, the Gunnison
County Sage-Grouse Conservation Action Plan (Gunnison County 2013a,
Appendix F) was developed to guide and prioritize the implementation of
specific conservation actions identified in the Strategic Plan.
Gunnison County and the Gunnison Basin Sage-Grouse Strategic Committee
(local working group for the Gunnison Basin population area) have also
made significant public outreach efforts including holding the Gunnison
Sage-Grouse Festival, providing Web site information for the public,
and education and communication with area landowners (Gunnison County
2013a, p. 59).
The Crawford Working Group (Delta and Montrose County areas) also
hired a Gunnison sage-grouse coordinator in December 2009. Likewise,
Saguache County hired a part-time coordinator for the Poncha Pass
population in 2013. These efforts facilitate coordination relative to
sage-grouse management and reflect positively on these counties'
commitment to Gunnison sage-grouse conservation.
[[Page 69267]]
Gunnison County and several other counties in the species' range
have also enacted regulatory and related measures to benefit Gunnison
sage-grouse and its habitat, as discussed under Factor D (Local Laws
and Regulation).
The Gunnison Climate Adaptation Pilot Project, led by the Gunnison
Climate Change Working Group, implemented several habitat projects in
2012 and 2013 to restore and improve the resiliency of Gunnison sage
brood-rearing habitats (riparian areas and wet meadows) to address
climate change in the Gunnison Basin (The Nature Conservancy (TNC)
2012, entire). The projected vulnerability of the Gunnison Basin to
climate change was the primary impetus for the pilot project (see
Climate Change). Long-term monitoring will determine effectiveness of
the projects. Additional projects under this initiative are planned for
the future (The Nature Conservancy (TNC) 2011, p. 1).
A review of a database compiled by the CPW that included local,
State, and Federal ongoing and pending Gunnison sage-grouse
conservation actions in Colorado from 2005 to 2009 (CDOW 2009c, entire)
revealed a total of 224 individual conservation efforts, most of which
were habitat improvement or protection projects. As of 2012, 165 of
those efforts were completed, resulting in the treatment (enhancement
or restoration) of 9,324 ha (23,041 ac), or approximately 2.5 percent
of occupied Gunnison sage-grouse habitat. A monitoring component was
included in 45 percent of the completed efforts, although we do not
have information on their overall effectiveness. Five habitat
improvement or protection projects occurred between January 2011 and
September 2012, treating an additional 300 acres (CPW 2012b, p. 7).
Further discussions of habitat improvement projects occurred before
2005 and subsequent to the 2012 summary document (CPW 2012b, entire;
CPW 2014e, entire; CPW 2014g entire). These are not discussed here but
were considered. Individually, these projects are generally all
relatively small in scale, in relation to the individual populations
where they have occurred. Cumulatively, these conservation efforts are
providing a conservation benefit to the species, however, given the
general downward trend of many of the satellite populations and the
inability of these efforts to reduce threats such as residential
development, we find these conservation efforts are not effective at
reducing the threats acting on the species to the point where listing
the species is not warranted.
Multi-County Rangewide Efforts
In 2013, the ``Conservation Agreement for Gunnison Sage-grouse,''
and a Memorandum of Understanding, was drafted by 11 Colorado and Utah
Counties across the range of Gunnison sage-grouse (Gunnison, Saguache,
Dolores, Montezuma, Delta, Montrose, Hinsdale, Mesa, San Miguel, and
Ouray Counties in Colorado; and San Juan County in Utah) (hereafter,
County Coalition). To date, the Governors of the States of Colorado and
Utah; and County Commissioners from all nine counties in occupied range
from both States have signed the agreement. Hinsdale and Montezuma
Counties do not contain occupied range for Gunnison sage-grouse and,
therefore, did not sign the agreement. While the agreement itself is
not regulatory, signatories of the agreement committed to implementing
appropriate resolutions, regulations, and guidelines to enhance the
species and its habitat in an effort to increase populations of
Gunnison sage-grouse (County Coalition 2013, entire). Specifically,
they have formally committed to adopting a Habitat Prioritization Tool,
which will better predict preferred habitat for the species, and they
have formally committed to updating and adopting an amended Rangewide
Conservation Plan. We did evaluate these multi-county efforts under our
PECE policy, but found they did not include specific conservation
efforts as defined by the PECE policy, and hence cannot contribute to a
determination that listing is unnecessary or a determination to list
the species as threatened rather than endangered.
Summary of Conservation Programs and Efforts Related to Habitat
Protection
Numerous conservation actions have been implemented for Gunnison
sage-grouse, and these efforts have provided and will continue to
provide conservation benefit to the species. The CCAA and CCA provide
significant conservation benefit to the species and its habitat on
private lands rangewide and Federal lands in the Gunnison Basin,
respectively, reducing the impacts of primarily habitat-related threats
in those areas. However, the identified conservation efforts, taken
individually and in combination, do not fully address the substantial
threats of rangewide habitat decline (Factor A), small population size
and structure (Factor E), drought (Factor E), climate change (Factor
A), and disease (Factor C). The Gunnison Basin CCA provides some
protection for Gunnison sage-grouse on Federal lands in the Gunnison
Basin, but does not cover the remaining, more vulnerable satellite
populations. Similarly, the existing CCAA benefits Gunnison sage-
grouse, but does not provide sufficient coverage of the species' range
to ensure the species' long-term conservation. Based on their voluntary
nature and track records, the RCP, local working group plans, and other
conservation efforts are not effective at reducing the threats acting
on the species to the point where listing the species is not warranted.
Thus, although the ongoing conservation efforts are a positive step
toward the conservation of the Gunnison sage-grouse and have
undoubtedly reduced the severity of certain threats to populations, on
the whole we find that current conservation efforts are not sufficient
to offset the full scope of threats to Gunnison sage-grouse.
Summary of Factor A
Gunnison sage-grouse require large areas of sagebrush for long-term
persistence, and thus are affected by factors that occur at the
landscape scale. Broad-scale characteristics within surrounding
landscapes influence habitat selection, and adult Gunnison sage-grouse
exhibit a high fidelity to all seasonal habitats, resulting in low
adaptability to habitat changes. Habitat loss, degradation, and
fragmentation of sagebrush habitats are a primary cause of the decline
of Gunnison and greater sage-grouse populations (Patterson 1952, pp.
192-193; Connelly and Braun 1997, p. 4; Braun 1998, p. 140; Johnson and
Braun 1999, p. 78; Connelly et al. 2000a, p. 975; Miller and Eddleman
2000, p. 1; Schroeder and Baydack 2001, p. 29; Johnsgard 2002, p. 108;
Aldridge and Brigham 2003, p. 25; Beck et al. 2003, p. 203; Pedersen et
al. 2003, pp. 23-24; Connelly et al. 2004, p. 4-15; Schroeder et al.
2004, p. 368; Leu et al. 2011, p. 267). Documented negative effects of
fragmentation include reduced lek persistence, lek attendance,
population recruitment, yearling and adult annual survival, female nest
site selection, and nest initiation rates, as well as the loss of leks
and winter habitat (Holloran 2005, p. 49; Aldridge and Boyce 2007, pp.
517-523; Walker et al. 2007a, pp. 2651-2652; Doherty et al. 2008, p.
194).
We examined a number of factors that contribute to habitat decline.
Habitat loss due to residential and infrastructural development
(including roads and powerlines) is a current and future threat to
Gunnison sage-grouse range-wide. Due to habitat decline, the seven
individual populations are now mostly isolated, with limited migration
and gene flow among populations,
[[Page 69268]]
increasing the likelihood of population extirpations. Functional
habitat loss also contributes to habitat decline as sage-grouse avoid
areas due to human activities and noise, even when sagebrush remains
intact. The collective disturbance from human activities around
residences and infrastructure results in habitat decline that
negatively impacts Gunnison sage-grouse survival. Human populations are
increasing across the species' range, a trend expected to continue into
the future. Resulting habitat decline is diminishing the probability of
Gunnison sage-grouse survival and persistence, particularly in the
satellite populations.
Other habitat-related threats that are impacting Gunnison sage-
grouse include grazing practices inconsistent with local ecological
conditions, fences, invasive plants, fire, mineral development,
pi[ntilde]on-juniper encroachment, and large-scale water development
and irrigation. The cumulative presence of all these features and
activities constitutes a threat to Gunnison sage-grouse as they
collectively contribute to habitat decline. In particular, the
satellite populations are less resilient and more vulnerable to
extirpation and environmental pressures including habitat loss and
fragmentation (see discussion in Factor A analysis above and in the
Factor E analysis below).
Several issues discussed above, such as fire, invasive species, and
pi[ntilde]on-juniper encroachment, may not currently have a substantial
impact on Gunnison sage-grouse. For example, while it may be impacting
individual birds or populations, pi[ntilde]on-juniper encroachment does
not currently pose a threat to the species because of its limited
distribution throughout the range of Gunnison sage-grouse. However, the
documented synergy among these three issues (pi[ntilde]on-juniper
encroachment, fire and invasive species), results in a high likelihood
that they will pose a threat to the species in the future. Nonnative
invasive plants, including cheatgrass and other noxious weeds, continue
to expand their range, facilitated by ground disturbances such as fire,
grazing incompatible with local ecological conditions, and human
infrastructure. Invasive plants negatively impact Gunnison sage-grouse
primarily by reducing or eliminating native vegetation that sage-grouse
require for food and cover, resulting in habitat decline (both direct
and functional). Cheatgrass is present at varying levels in nearly all
Gunnison sage-grouse population areas, but there has not yet been a
demonstrated change in fire cycle in the range of Gunnison sage-grouse.
However, climate change will likely alter the range of invasive plants,
intensifying the proliferation of invasive plants to the point that
they become a threat to the species. Even with aggressive treatments,
invasive plants will likely persist and continue to spread throughout
the range of Gunnison sage-grouse.
Livestock management inconsistent with local ecological conditions
has the potential to degrade sage-grouse habitat at local scales by
causing the loss of nesting cover and decreases in native vegetation,
and by increasing the probability of incursion of invasive plants.
Given the widespread nature of grazing within the range of Gunnison
sage-grouse, the potential for population-level impacts is probable.
Effects of domestic livestock grazing inconsistent with local
ecological conditions are likely being exacerbated by intense browsing
of woody species by wild ungulates in parts of the Gunnison Basin. We
conclude that habitat degradation that can result from grazing
practices inconsistent with local ecological conditions is a threat to
Gunnison sage-grouse.
We do not consider nonrenewable energy development to be impacting
Gunnison sage-grouse habitat to the extent that it is a threat to the
long-term persistence of the species at this time, because its current
and anticipated extent is limited throughout the range of Gunnison
sage-grouse. We do not consider renewable energy development to be a
threat to the persistence of Gunnison sage-grouse rangewide at this
time. However, geothermal and wind energy development could increase in
the Gunnison Basin and Monticello areas, respectively, in the future.
We recognize ongoing and proposed conservation efforts by all
entities across the range of the Gunnison sage-grouse, and commend all
parties for their vision and participation. Local communities,
landowners, agencies, and organizations in Colorado and Utah have
dedicated resources to Gunnison sage-grouse conservation and have
implemented numerous conservation efforts. We encourage continued
implementation of these efforts into the future to promote the
conservation of Gunnison sage-grouse. Our review of conservation
efforts indicates that the measures identified are not fully addressing
the most substantial threats to Gunnison sage-grouse including habitat
decline (Factor A), small population size and structure (Factor E),
drought (Factor E), climate change (Factor A), and disease (Factor C).
All of the conservation efforts are limited in size and the measures
provided to us were not implemented at the scale (even when considered
cumulatively) that would be required to effectively reduce the threats
to the species and its habitat across its range. The Gunnison Basin
CCA, for example, provides some protection for Gunnison sage-grouse on
Federal lands in the Gunnison Basin, but does not cover the remaining,
more vulnerable satellite populations. Similarly, the existing CCAA
benefits Gunnison sage-grouse on participating lands, but does not
provide sufficient coverage of the species' range to ensure the
species' long-term conservation. Thus, although the ongoing
conservation efforts are a positive step toward the conservation of the
Gunnison sage-grouse, and some have likely reduced the severity of some
threats to the species, on the whole we find that current conservation
efforts are not sufficient to offset the full scope of threats to
Gunnison sage-grouse.
We have evaluated the best scientific information available on the
present or threatened destruction, modification, or curtailment of the
Gunnison sage-grouse's habitat or range. Based on the current and
anticipated habitat threats identified above and their cumulative
effects as they contribute to the overall decline of Gunnison sage-
grouse habitat, we have determined that the present or threatened
destruction, modification, or curtailment of Gunnison sage-grouse
habitat poses a threat to the species throughout its range. This threat
is substantial and current, and is projected to continue and increase
into the future with additional anthropogenic pressures.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Hunting
Hunting for Gunnison sage-grouse is not currently permitted under
Colorado and Utah law. Hunting was eliminated in the Gunnison Basin in
2000 due to concerns with meeting Gunnison sage-grouse population
objectives (Colorado Sage Grouse Working Group (CSGWG) 1997, p. 66).
Hunting has not occurred in the other Colorado populations of Gunnison
sage-grouse since 1995 when the Pi[ntilde]on Mesa area was closed
(GSRSC 2005, p. 122). Utah has not allowed hunting of Gunnison sage-
grouse since 1989 according to GSRSC (2005, p. 82), or as early as the
mid-1970's according to SJCWG (2000, p. 11).
Both Colorado and Utah report they will consider hunting of
Gunnison sage-grouse only if populations can be sustained (GSRSC 2005,
pp. 5, 8, 229). The local Gunnison Basin working group plan calls for a
minimum
[[Page 69269]]
population of 500 males (based on lek counts) before hunting would
occur again (CSGWG 1997, p. 66). The minimum population level in the
Gunnison Basin population has been exceeded in all years since 1996,
except 2003 and 2004 (CDOW 2009d, pp. 18-19). However, the sensitive
State regulatory status and potential political ramifications of
hunting the species has precluded the States from opening a hunting
season. If hunting does ever occur again, harvest will likely be
restricted to only 5 to 10 percent of the fall population, and will be
structured to limit harvest of females to the extent possible (GSRSC
2005, p. 229). However, the ability of these measures to be implemented
is in question, as adequate means to estimate fall population size have
not been developed (Reese and Connelly 2011, pp. 110-111) and limiting
female harvest may not be possible (WGFD 2004, p. 4; WGFD 2006, pp. 5,
7).
In 1992, a CPW effort to simplify hunting restrictions
inadvertently opened the Poncha Pass area to sage-grouse hunting, and
at least 30 grouse were harvested from this population. The area was
closed to sage-grouse hunting the following year and has remained
closed to hunting since (Nehring and Apa 2000, p. 3). One sage-grouse
was known to be illegally harvested in 2001 in the Poncha Pass
population (Nehring 2010, pers. comm.), but based on the best available
information illegal harvest has not contributed to Gunnison sage-grouse
population declines in either Colorado or Utah. We do not anticipate
hunting to be opened in the Gunnison Basin or smaller populations for
many years, if ever. Consequently, we do not consider hunting to be a
threat to the species now or in the future.
Lek Viewing and Counts
The Gunnison sage-grouse was designated as a new species in 2000
(American Ornithologists' Union 2000, pp. 847-858), which has prompted
a much increased interest by bird watchers to view the species on their
leks (Pfister 2010, pers. comm.). Daily human disturbances on sage-
grouse leks could cause a reduction in mating, and some reduction in
total production (Call and Maser 1985, p. 19). Human disturbance,
particularly if additive to disturbance by predators, could reduce the
time a lek is active, as well as reduce its size by lowering male
attendance (Boyko et al. 2004, in GSRSC 2005, p. 125). Smaller lek
sizes have been hypothesized to be less attractive to females, thereby
conceivably reducing the numbers of females mating. Disturbance during
the peak of mating also could result in some females not breeding
(GSRSC 2005, p. 125). Furthermore, disturbance from lek viewing might
affect nesting habitat selection by females (GSRSC 2005, p. 126), as
leks are typically close to areas in which females nest. If females
move to poorer quality habitat farther away from disturbed leks, nest
success could decline. If chronic disturbance causes sage-grouse to
move to a new lek site away from preferred and presumably higher
quality areas, both survival and nest success could decline. Whether
any or all of these have significant population effects would depend on
timing and degree of disturbance (GSRSC 2005, p. 126).
Throughout the range of Gunnison sage-grouse, public viewing of
leks is limited by a general lack of knowledge of lek locations,
seasonal road closures in some areas, and difficulty in accessing many
leks. Furthermore, 52 of 109 active Gunnison sage-grouse leks occur on
private lands, further limiting public access. The BLM closed a lek in
the Gunnison Basin to viewing in the late 1990s due to declining
population counts perceived as resulting from recreational viewing,
although no scientific studies were conducted (BLM 2005a, p. 13; GSRSC
2005, pp. 124, 126).
The Waunita lek east of Gunnison is the only lek in Colorado
designated by the CPW for public viewing (Waunita Watchable Wildlife
Area) (CDOW 2009b, p. 86). Since 1998, a comparison of male counts on
the Waunita lek versus male counts on other leks in the Doyleville zone
show that the Waunita lek's male counts generally follow the same trend
as the others (CDOW 2009d, pp. 31-32). In fact, in 2008 and 2009, the
Waunita lek increased in the number of males counted along with three
other leks, while seven leks decreased in the Doyleville zone (CDOW
2009d, pp. 31-32). These data suggest that lek viewing on the Waunita
lek has not impacted Gunnison sage-grouse attendance at leks. Two lek
viewing tours per year are organized and led by UDWR on a privately
owned lek in the Monticello population. The lek declined in males
counted in 2009, but 2007 and 2008 had the highest counts for several
years, suggesting that lek viewing is not impacting that lek either.
Data collected by CPW on greater sage-grouse viewing leks also
indicates that controlled lek visitation has not impacted greater sage-
grouse at the viewed leks (GSRSC 2005, p. 124).
A lek viewing protocol has been developed and has largely been
followed on the Waunita lek, likely reducing impacts to sage-grouse
(GSRSC 2005, p. 125). During 2004-2009, the percentage of individuals
or groups of people in vehicles following the Waunita lek viewing
protocol in the Gunnison Basin ranged from 71 to 92 percent (CDOW
2009b, pp. 86, 87; Magee et al. 2009, pp. 7, 10). Violations of the
protocol, such as showing up after the sage-grouse started to display
and creating noise, caused one or more sage-grouse to flush from the
lek (CDOW 2009b, pp. 86, 87). Despite the protocol violations, the
percentage of days from 2004 to 2009 that grouse were flushed by humans
was relatively low, ranging from 2.5 percent to 5.4 percent (Magee et
al. 2009, p. 10). The current lek viewing protocol includes regulations
to avoid and minimize disturbance from photography, research, and
education-related viewing; regulations and related information are
provided to the public online (CDOW 2009b, p. 86; Gunnison County
2013a, p. 127; CPW 2013, entire). Implementation of this protocol
should preclude lek viewing from becoming a threat to this lek.
The CPW and UDWR will continue to coordinate and implement lek
counts to determine population levels. We expect annual lek viewing and
lek counts to continue into the future. Lek counts may disturb
individual birds. However, since the Waunita lek is open to viewers on
a daily basis throughout the lekking season, and lek counters only
approach an individual lek 2-3 times per season, all leks counted will
receive lower disturbance from counters than the Waunita lek receives
from public viewing, so we do not consider lek counts a threat to
Gunnison sage-grouse populations or the species.
Scientific Research and Related Conservation Efforts
Overall, it is expected that scientific research and related
conservation efforts by the States, such as translocation of Gunnison
sage-grouse, have a net conservation benefit for the species, because
they contribute to improved understanding of the species' conservation
needs and may have helped to augment some of the satellite populations,
likely contributing to their continued persistence. However, some
unintended negative effects are known to occur in the process. Gunnison
sage-grouse have been the subject of multiple scientific studies, some
of which included capture and handling. Most field research has been
conducted in the Gunnison Basin population, San Miguel Basin
population, and Monticello portion of the Monticello-Dove Creek
population. Between zero and seven percent mortality of handled adults
or
[[Page 69270]]
juveniles and chicks has occurred during recent Gunnison sage-grouse
studies where trapping and radio-tagging was done (Apa 2004, p. 19;
Childers 2009, p. 14; Lupis 2005, p. 26; San Miguel Basin Gunnison
Sage-grouse Working Group (SMBGSWG) 2009, p. A-10). For these studies
combined, of 688 birds captured, 11 (1.6 percent) died (Table 11).
Additionally, one radio-tagged hen was flushed off a nest during
subsequent monitoring and did not return after the second day,
resulting in the loss of 10 eggs (Ward 2007, p. 52). The CPW does not
feel that these losses or disturbance are having significant impacts on
the sage-grouse (CDOW 2009b, p. 29), and we agree with this assessment.
Table 11--Mortality of Gunnison Sage-Grouse From Recent Studies
----------------------------------------------------------------------------------------------------------------
Total birds Mortality
handled/ --------------------------------
Study focus captured/ Number of % of total Source
studied individuals birds
----------------------------------------------------------------------------------------------------------------
Habitat use, movement, survival of 138 3 2.2 Apa 2004, p. 19.
Gunnison sage-grouse in southwest
Colorado.
Gunnison sage-grouse habitat use...... \a\ 336 7 2.1 Childers 2009, p. 14.
Summer ecology of Gunnison sage-grouse 14 1 7.1 Lupis 2005, p. 26.
Summary of CPW research projects in 200 0 0.0 SMBGSWG 2009, p. A-10.
the Gunnison Basin and San Miguel
populations from 2004 to 2009.
------------------------------------------------
Total............................. 688 11 1.6 n/a.
----------------------------------------------------------------------------------------------------------------
\a\ This figure includes 218 adults and 118 chicks captured; of these, 5 adults (2.3%) and 2 chicks (1.7%) died.
Translocation of birds from the Gunnison Basin population has been
used to augment some of the satellite populations and may contribute to
their persistence. However, related to translocated birds, there are
potential genetic and population viability concerns for the satellite
(receiving) populations and the Gunnison Basin (source) population (see
Small Population Size and Structure in Factor E). Trapping and
translocation of Gunnison sage-grouse may also increase mortality
rates, either due directly to capturing and handling, or indirectly
(later in time) as a result of translocation to areas outside the
individuals' natal (home) range.
From the spring of 2000 to the spring 2013, CPW translocated a
total of 300 radio-collared Gunnison sage-grouse from the Gunnison
Basin population to the following satellite populations: Poncha Pass
(41 birds), San Miguel Basin (Dry Creek Basin) (51 birds), Pi[ntilde]on
Mesa (93 birds), Dove Creek (42 birds), and Crawford (73 birds). During
this time, CPW reported only four bird deaths associated with capture
myopathy (muscle damage due to extreme exertion or stress associated
with capture and transport), including two deaths in 2007 and two in
2009 (CPW 2014c, entire). Excluding capture myopathy cases, data for
birds with unknown fates (i.e., due to dropped or expired radio
collars), and some of the more recent (2013) translocated birds, CPW
has tracked the survival of 176 Gunnison sage-grouse translocated to
date. Survival of all translocated birds to 12 months following
translocation was higher in the spring (53.8 percent) than fall (39.6
percent); higher for yearlings (55.4 percent) and juveniles (61.3
percent) than adults (40.0 percent); and comparable for males (50.0
percent) and females (48.8 percent). By population, survival to 12
months was highest in Dove Creek (60 percent) and Crawford (59.6
percent), followed by Pi[ntilde]on Mesa (40 percent), Dry Creek Basin
(35.3 percent), and Poncha Pass (20.0 percent). Overall survival of
translocated birds to 12 months was approximately 48 percent (CPW
2013d, entire; Wait 2013, pers. comm.; CPW 2014c, entire). Therefore,
about 50 percent of these translocated birds died within the first 12
months following translocation, greater than the average annual
mortality rate of non-translocated sage-grouse (approximately 20
percent) (CDOW 2009b, p. 9). However, some birds with an unknown fate
(e.g., a dropped radio collar with no sign of death) were assumed dead
and, therefore, the data may overestimate actual mortality rates (Wait
2013, pers. comm.).
In the fall of 2013, an additional 17 Gunnison sage-grouse were
translocated to the Poncha Pass population from the Gunnison Basin. As
of January 2014, 10 of these birds were known to be surviving (Nehring
2014, pers. comm.). In spring of 2014, 10 more birds were translocated
to the Poncha Pass population from the Gunnison Basin (CPW 2014e, p.
7). In the fall of 2013 and spring of 2014, CPW translocated 23 birds
from the Gunnison Basin to the Miramonte subpopulation of the San
Miguel population (CPW 2014e, p. 7). Survival data for these birds were
not available upon the drafting of this final rule.
Greater sage-grouse translocations have not fared any better than
those of Gunnison sage-grouse. Over 7,200 greater sage-grouse were
translocated between 1933 and 1990, but only five percent of the
translocation efforts were considered to be successful in producing
sustained, resident populations at the translocation sites (Reese and
Connelly 1997, pp. 235-238, 240). More recent translocations from 2003
to 2005 into Strawberry Valley, Utah, resulted in a 40 percent annual
mortality rate (Baxter et al. 2008, p. 182). We believe the lack of
success of translocations found in greater sage-grouse is applicable to
Gunnison sage-grouse because the two species exhibit similar behavior
and life-history traits, and translocations are also managed similarly.
Because the survival rate for translocated sage-grouse has not been
as high as desired, the CPW started a captive-rearing program in 2009
to investigate techniques for captive breeding and rearing of chicks,
and methods to release chicks into wild, surrogate broods, to
potentially increase brood survival and recruitment (CDOW 2009b, pp. 9-
12). The GSRSC conducted a review of captive-rearing attempts for both
greater sage-grouse and other gallinaceous birds and concluded that
survival will be very low, unless innovative strategies are developed
and tested (GSRSC 2005, pp. 181-183). However, greater sage-grouse have
been reared in captivity, and survival of released chicks was similar
to that of wild chicks (CDOW 2009b, p. 10). Consequently, the CPW
started a captive-breeding project for Gunnison sage-grouse. After
establishing a captive,
[[Page 69271]]
breeding flock, 78 domestically-reared chicks were introduced to wild
Gunnison sage-grouse broods in 2010 and 2011 at two treatment ages.
While survival of successfully-adopted, domestically-reared chicks was
slightly lower than that of wild-reared chicks through 14 weeks, across
both years none of the domestically-reared chicks were recruited into
the breeding population (Wiechman 2014c, pers. comm.). Although
introduced chick survival was relatively low, chick survival during
captivity increased with improved protocols, and valuable knowledge on
Gunnison sage-grouse rearing techniques has been gained (CPW 2011b). In
another study, approximately 42 percent of captive-reared chicks
introduced to wild females and their broods survived to 30 days of age.
Of chicks that did not survive, 26.3 percent of chicks were lost due to
predation, and 25.6 percent were lost due to exposure to the elements
(Thompson 2012, pp. 29, 93).
As techniques improve, the CPW intends to develop a captive-
breeding manual for Gunnison sage-grouse (CDOW 2009b, p. 11). Although
adults or juveniles have been captured and moved out of the Gunnison
Basin, as well as eggs, the removal of the grouse only accounts for a
very small percentage of the total population of the Gunnison Basin
sage-grouse population (less than 1 percent per year).
The CPW has a policy regarding trapping, handling, and marking
techniques approved by its Animal Use and Care Committee (SMBGSWG 2009,
p. A-10, Childers 2009, p. 13). Evaluation of research projects by the
Animal Use and Care Committee and improvement of trapping, handling,
and marking techniques over the last several years has resulted in
fewer mortalities and injuries. In fact, in the San Miguel Basin,
researchers have handled more than 200 sage-grouse with no trapping
mortalities (SMBGSWG 2009, p. A-10). The CPW has also drafted a sage-
grouse trapping and handling protocol, which is required training for
people handling Gunnison sage-grouse, to minimize mortality and injury
of the birds (CDOW 2002, pp. 1-4 in SMBWG 2009, pp. A-22-A-25). Injury
and mortality does occasionally occur from trapping, handling, marking,
and flushing off nests. However, research-related mortality is
typically below two percent of handled birds (Table 11), indicating
there is minimal effect on Gunnison sage-grouse at the population
level.
Overall, we find that ongoing and future scientific research and
related conservation efforts provide a net conservation benefit for the
species. Primarily due to handling, capture, and translocations, short-
term negative effects to individuals occur as does injury and
mortality, but these effects do not pose a threat to Gunnison sage-
grouse populations or the species. Translocation of birds from the
Gunnison Basin population has been used to augment some of the
satellite populations and may have contributed to their persistence,
albeit with potential genetic and population viability concerns for the
receiving populations (see Genetic Risks), and for the Gunnison Basin
(source) population (see Small Population Size and Structure in Factor
E). Based on the best available information, scientific research and
associated activities as described above have a relatively minor impact
and are not a threat to the Gunnison sage-grouse.
Summary of Factor B
We have no evidence to suggest that legal hunting resulted in the
overutilization of Gunnison sage-grouse. However, Gunnison sage-grouse
harvest from an inadvertently opened hunting season resulted in a
significant population decrease in the small Poncha Pass population.
Nevertheless, we do not expect hunting to be permitted in the near
future. Illegal hunting has only been documented once in Colorado and
is not a known threat in Colorado or Utah. Lek viewing has not affected
the Gunnison sage-grouse, and lek viewing protocols designed to reduce
disturbance have generally been followed. CPW is currently revising its
lek viewing protocol to make it more stringent and to include
considerations for photography, research, and education-related
viewing. Mortality from scientific research and capture or handling of
wild birds is low, generally less than 2 percent and is not a threat.
We know of no overutilization for commercial or educational purposes.
Thus, based on the best scientific and commercial data available, we
conclude that overutilization for commercial, recreational, scientific,
or educational purposes is not a threat to Gunnison sage-grouse.
C. Disease or Predation
Disease
No research focusing on the types or pathology of diseases in
Gunnison sage-grouse has been published. However, multiple bacterial
and parasitic diseases have been documented in greater sage-grouse
(Patterson 1952, pp. 71-72; Schroeder et al. 1999, pp. 14, 27). Some
early studies have suggested that greater sage-grouse populations are
adversely affected by parasitic infections (Batterson and Morse 1948,
p. 22). However, the role of parasites or infectious diseases in
population declines of greater sage-grouse is unknown based on the few
systematic surveys conducted (Connelly et al. 2004, p. 10-3). No
parasites have been documented to cause mortality in Gunnison sage-
grouse, but the protozoan, Eimeria spp., which causes coccidiosis, has
been reported to cause death in greater sage-grouse (Connelly et al.
2004, p. 10-4). Infections tend to be localized to specific geographic
areas, and no cases of greater sage-grouse mortality resulting from
coccidiosis have been documented since the early 1960s (Connelly et al.
2004, p. 10-4).
Parasites have been implicated in greater sage-grouse mate
selection, with potentially subsequent effects on the genetic diversity
of this species (Boyce 1990, p. 263; Deibert 1995, p. 38). These
relationships may be important to the long-term ecology of greater
sage-grouse, but they have not been shown to be significant to the
immediate status of populations (Connelly et al. 2004, p. 10-6).
Although diseases and parasites have been suggested to affect isolated
sage-grouse populations (Connelly et al. 2004, p. 10-3), we have no
evidence indicating that parasitic diseases are a threat to Gunnison
sage-grouse populations.
Greater sage-grouse are subject to a variety of bacterial, fungal,
and viral pathogens. The bacterium Salmonella sp. has caused a single
documented mortality in the greater sage-grouse and studies have shown
that infection rates in wild birds are low (Connelly et al. 2004, p.
10-7). The bacteria are apparently contracted through exposure to
contaminated water supplies around livestock stock tanks (Connelly et
al. 2004, p. 10-7). Other bacteria found in greater sage-grouse include
Escherichia coli, botulism (Clostridium spp.), avian tuberculosis
(Mycobacterium avium), and avian cholera (Pasteurella multocida). These
bacteria have never been identified as a cause of mortality in greater
sage-grouse and the risk of exposure and hence, population effects, is
low (Connelly et al. 2004, p. 10-7 to 10-8). In Gunnison sage-grouse,
domestically-reared chicks have died due to bacterial infections by
Klebsiella spp., E. coli, and Salmonella spp. In one case (CDOW 2009b,
p. 11), bacterial growth was encouraged by a wood-based brooder
substrate used to raise chicks. However, in a subsequent study (CPW
2011b, pp. 14-15) where the wood-based substrate was not used, similar
bacterial infections and chick mortality still occurred. This was
likely
[[Page 69272]]
a product of warm and potential moist substrates which promoted
bacterial growth and spread. After switching to a gravel-based
substrate and administering antibiotics, bacteria-related mortalities
decreased. While this appears to suggest that Gunnison sage-grouse may
be less resistant to bacterial infections than greater sage-grouse,
most of the bacteria found can be present at non-lethal levels in wild
Gunnison sage-grouse (Wiechman 2014a, pers. comm.). However, we have no
information that shows the risk of exposure in the wild is different
for Gunnison sage-grouse; therefore, these bacteria do not appear to be
a threat to the species.
To limit the risk of disease transmission from introduced avian
species, Gunnison County's Land Use Resolution (LUR) Number 07-17
regulates the importation of non-indigenous, gallinaceous game birds.
This regulation requires that species only be imported from a source
certified by the State of Colorado to be disease free (Gunnison County
2013a, p. 130).
West Nile virus was introduced into the northeastern United States
in 1999 and has subsequently spread across North America (Marra et al.
2004, p. 394). Greater sage-grouse are highly susceptible to West Nile
virus (Clark et al. 2006, p. 19; McLean 2006, p. 54) and do not develop
a resistance to the disease. Death is almost certain once an individual
is infected with the disease (Clark et al. 2006, p. 18). Transmission
occurs when mosquitoes acquire the virus by biting an infected bird,
and then transfer it by feeding on a new host (avian or mammalian).
Culex species are recognized as the most efficient mosquito vectors for
West Nile virus (Turell et al. 2005, p. 60), and Culex tarsalis is the
dominant vector of the virus in sagebrush habitats (Naugle et al. 2004,
p. 711). West Nile virus transmission is regulated by multiple factors,
including temperature, precipitation, biology of the mosquito vector
(Turrell et al. 2005, pp. 59-60), and the presence of anthropogenic
water sources, such as stock ponds and tanks, coal bed methane ponds,
and irrigated agricultural fields that support mosquito life cycles
(Reisen et al. 2006, p. 309; Walker and Naugle 2011, pp. 131-132). The
peak of West Nile virus activity typically occurs in the summer from
July through August, though this varies by region (Walker et al. 2004).
In Gunnison sage-grouse range and other parts of the west, water
sources are commonly developed to support livestock operations and
improve animal distribution and forage use. Some water developments are
designed specifically to benefit Gunnison sage-grouse, although this
practice was recommended prior to our knowledge of West Nile virus as a
serious risk factor for sage-grouse (Walker and Naugle 2011, p. 29)
(see discussion below; also see discussion of the potential benefits of
water development to Gunnison sage-grouse in Domestic Grazing and
Wildlife Herbivory in Factor A above). The precise quantity and
distribution of water developments in Gunnison sage-grouse range is
unknown. However, we know that at least 87 percent of occupied Gunnison
sage-grouse habitat on Federal lands is currently grazed by domestic
livestock (USFWS 2010c, entire), suggesting that water developments are
common and widespread across the species range. A similar proportion of
area on private lands is likely grazed by domestic livestock as well.
It is expected that some of these water sources are contributing to the
persistence of mosquito populations and, therefore, to the potential
spread of West Nile virus across the range of Gunnison sage-grouse.
Management or modification of water developments in sage-grouse
habitats is one way to control mosquito vector populations and,
therefore, sources of West Nile virus (Walker and Naugle 2011, p. 29,
and references therein).
The virus persists largely within a mosquito-bird-mosquito
infection cycle (McLean 2006, p. 45). However, direct bird-to-bird
transmission of the virus has been documented in several species
(McLean 2006, pp. 54, 59), including the greater sage-grouse (Walker
and Naugle 2011, p. 132; Cornish 2009, pers. comm.). The frequency of
direct transmission has not been determined (McLean 2006, p. 54). Cold
ambient temperatures preclude mosquito activity and virus
amplification, so transmission to and in sage-grouse is limited to the
summer (mid-May to mid-September) (Naugle et al. 2005, p. 620; Zou et
al. 2007, p. 4), with a peak in July and August (Walker and Naugle
2011, p. 131). Reduced and delayed West Nile virus transmission in
sage-grouse has occurred in years with lower summer temperatures
(Naugle et al. 2005, p. 621; Walker et al. 2007b, p. 694). In non-
sagebrush ecosystems, high temperatures associated with drought
conditions increase West Nile virus transmission by allowing for more
rapid larval mosquito development and shorter virus incubation periods
(Shaman et al. 2005, p. 134; Walker and Naugle 2011, p. 131).
Greater sage-grouse congregate in mesic (moist) habitats in the
mid-late summer (Connelly et al. 2000, p. 971), thereby increasing
their risk of exposure to mosquitoes. Likewise, Gunnison sage-grouse
use more mesic habitats in the summer and early fall (GSRSC 2005, p.
30, and references therein), increasing their exposure to mosquitoes.
If West Nile virus outbreaks coincide with drought conditions that
aggregate birds in habitat near water sources, the risk of exposure to
West Nile virus will be elevated (Walker and Naugle 2011, p. 131).
Greater sage-grouse inhabiting higher elevation sites in summer
(similar to areas of the Gunnison Basin) are likely less vulnerable to
contracting West Nile virus than birds at lower elevation (similar to
Dry Creek Basin of the San Miguel population) as ambient temperatures
are typically cooler at higher elevations (Walker and Naugle 2011, p.
131).
West Nile virus has caused population declines in wild bird
populations on the local and regional scale (Walker and Naugle 2011,
pp. 128-129) and has reduced the survival rates of greater sage-grouse
(Naugle et al. 2004, p. 710; Naugle et al. 2005, p. 616). Experimental
results, combined with field data, suggest that a widespread West Nile
virus infection has negatively affected greater sage-grouse (Naugle et
al. 2004, p. 711; Naugle et al. 2005, p. 616). As noted above, the
selective use of mesic habitats by sage-grouse during the summer and
fall increases their exposure to West Nile virus. Greater sage-grouse
are highly susceptible to West Nile virus (Clark et al. 2006, p. 19;
McLean 2006, p. 54) and do not develop a resistance to the disease.
Death is certain once an individual is infected with the disease (Clark
et al. 2006, p. 18). Furthermore, other gallinaceous bird species such
as ruffed grouse (Bonasa umbellus), wild turkey (Meleagris gallopavo),
and chukar partridge (Alectoris chukar), have died as a result of West
Nile virus infection (CDC 2013, entire).
It is reasonable to assume the Gunnison sage-grouse is susceptible
to West Nile virus based on the confirmed cases of infection and
mortality in greater sage-grouse and other taxonomically related birds.
We are also aware of at least 3 Gunnison sage-grouse dying of West Nile
disease, although these birds were growing in captivity in Fort
Collins, CO where the virus is more likely to be present (Wiechman
2014b, pers. comm). To date, however, West Nile virus has not been
documented in Gunnison sage-grouse despite the presence of West Nile
virus across most of the species' range (see discussion below). This
may be the result of the small number of birds marked and studied;
limited local abundance of the principle mosquito vector species,
[[Page 69273]]
Culex; unsuitable conditions in Gunnison sage-grouse habitat for the
virus to become virulent or widespread; or any number of other factors.
West Nile virus activity within the range of Gunnison sage-grouse is
apparently low compared to other parts of Colorado, Utah, and the
western United States. However, West Nile virus surveillance may not
occur every year or in every county (USGS 2013, entire), meaning that
incidents likely go undetected. Furthermore, rural areas with smaller
human populations, such as the majority of lands within Gunnison sage-
grouse range, may have decreased detection and reporting rates of avian
mortalities, thus potentially biasing the modeled distribution of West
Nile virus (Ward et al. 2006, p. 102).
To date, across Gunnison sage-grouse occupied range, only San
Miguel and Dolores, Counties in Colorado have no confirmed avian
mortalities associated with West Nile virus, nor has the virus been
reported in human or mosquito infection data in those counties.
However, adjacent counties have confirmed West Nile virus presence, so
the virus is potentially present in San Miguel and Dolores Counties as
well. A total of 84 dead wild birds (species other than Gunnison sage-
grouse) infected by West Nile virus have been reported from nine
counties within the current range of Gunnison sage-grouse since 2002,
when reporting began in Colorado and Utah. These include Chaffee,
Delta, Gunnison, Mesa, Montrose, Ouray, and Saguache Counties in
Colorado; and Grand and San Juan Counties in Utah. Seventy and 14 of
these bird deaths were reported in Colorado and Utah, respectively.
Fifty-two (62 percent) of reported cases were in Mesa County where the
Pi[ntilde]on Mesa population is found. Also, the majority of reported
cases were in Colorado counties (USGS 2013, entire; USFWS 2013a,
entire). However, as noted above, areas with higher human population
densities, such as Mesa County, Colorado, can result in increased
detection and reporting rates, thus potentially biasing the modeled
distribution of West Nile virus (Ward et al. 2006, p. 102). In Utah, 13
(93 percent) avian mortality reports were in Grand County, and 1 (7
percent) was in San Juan County. Sixty-four (76 percent) of the 84
total reported bird mortalities in Colorado and Utah occurred in 2003
and 2004, when summer temperatures were above average and, likely
contributing to the spread of West Nile virus (Reisen et al. 2006, p.
1). Since that time, reported avian mortalities associated with West
Nile virus across the range of Gunnison sage-grouse have declined, and
no avian infections or mortalities were reported from 2008 through 2012
(USGS 2013, entire; USFWS 2013a, entire).
A CPW study with the Colorado Mosquito Control Company in 2004 used
mosquito trap monitoring to evaluate the relative risk of West Nile
virus on Gunnison sage-grouse in the Gunnison Basin. Trapping resulted
in a total of 6,729 mosquitoes throughout the Gunnison Basin from June
1 through August 30. Testing of mosquito samples conducted by the
Colorado Department of Public Health observed nine species of mosquito,
including Culex tarsalis, the primary vector of West Nile virus.
However, the relative abundance of C. tarsalis was low, comprising
about 15.8 percent of all samples collected. No other Culex species
were observed. The other species observed are not known to be effective
transmitters of West Nile virus to avian species. All mosquito samples
tested negative for West Nile virus. Sixteen Gunnison sage-grouse were
radiomarked by CPW during the same summer, and no mortalities of marked
or unmarked birds were observed (Phillips 2013, p. 6). One avian
mortality (a species other than Gunnison sage-grouse) due to West Nile
infection was reported in Gunnison County in 2003 (USGS 2013, entire;
USFWS 2013a, p. 1).
Walker and Naugle (2011, p. 140) predict that West Nile virus
outbreaks in small, isolated, and genetically depauperate populations
could reduce sage-grouse numbers below a threshold from which recovery
is unlikely because of limited or nonexistent demographic and genetic
exchange from adjacent populations. If so, a West Nile virus outbreak
in any Gunnison sage-grouse population, except perhaps the Gunnison
Basin population, assuming it remains large and resilient, would
challenge their survival.
As described above, West Nile virus is present throughout most of
the range of Gunnison sage-grouse. Although the disease has not yet
been documented in any Gunnison sage-grouse, it has caused large
mortality events and has also caused the deaths of other gallinaceous
birds including greater sage-grouse. Similar to observations in greater
sage-grouse (Walker and Naugle 2011, p. 131), higher elevation
populations of Gunnison sage-grouse, such as the Gunnison Basin may be
at lower risk of West Nile virus infection and outbreaks. Also, the
frequency of avian mortalities (species other than sage-grouse)
associated with the virus have apparently declined since 2004 across
the range of Gunnison sage-grouse. However, increased temperature and
drought conditions are expected to increase in the future due to
climate change across the range (see Climate Change in Factor A). Such
conditions will contribute to the prevalence and spread of West Nile
virus and, therefore, the exposure of Gunnison sage-grouse to this
disease. Therefore, due to the known presence of West Nile virus across
the majority of Gunnison sage-grouse range, the high risk of mortality
and population-level impacts based on the biology of the species, and
the immediacy of those potential impacts, we conclude that West Nile
virus is a future threat to Gunnison sage-grouse rangewide. The threat
of West Nile virus is currently lower in the high elevation areas, such
as the Gunnison Basin population, but is expected to increase in the
foreseeable future due to increased drought and the predicted effects
of climate change. No other diseases or parasitic infections are known
to be a threat to Gunnison sage-grouse now or in the future.
Predation
Predation is the most commonly identified cause of direct mortality
for sage-grouse during all life stages (Schroeder et al. 1999, p. 9;
Connelly et al. 2000b, p. 228; Connelly et al. 2011b, p. 66). However,
sage-grouse have co-evolved with a variety of predators, and their
cryptic plumage and behavioral adaptations have allowed them to persist
despite this mortality factor (Schroeder et al. 1999, p. 10; Coates
2008, p. 69; Coates and Delehanty 2008, p. 635; Hagen 2011, p. 96).
Until recently, little published information has been available that
indicates predation is a limiting factor for the greater sage-grouse
(Connelly et al. 2004, p. 10-1), particularly where habitat quality has
not been compromised (Hagen 2011, p. 96). Although many predators will
consume sage-grouse, none specialize on the species (Hagen 2011, p.
97). Generalist predators have the greatest effect on ground-nesting
birds because predator numbers are independent of the density of a
single prey source since they can switch to other prey sources when a
given prey source is not abundant (Coates 2007, p. 4). We presume that
the effects of predation observed in greater sage-grouse are similar to
those anticipated in Gunnison sage-grouse since overall behavior and
life-history traits are similar for the two species. However, as
discussed below, those effects may be more substantial and of greater
concern for smaller, declining populations, such as the six satellite
populations of Gunnison sage-grouse.
[[Page 69274]]
Major predators of adult sage-grouse include many species including
golden eagles (Aquila chrysaetos), red foxes (Vulpes fulva), and
bobcats (Felis rufus) (Hartzler 1974, pp. 532-536; Schroeder et al.
1999, pp. 10-11; Schroeder and Baydack 2001, p. 25; Rowland and Wisdom
2002, p. 14; Hagen 2011, p. 97). Juvenile sage-grouse also are killed
by many raptors as well as common ravens (Corvus corax), badgers
(Taxidea taxus), red foxes, coyotes (Canis latrans), and weasels
(Mustela spp.) (Braun 1995, entire; Schroeder et al. 1999, p. 10). Nest
predators include badgers, weasels, coyotes, common ravens, American
crows (Corvus brachyrhyncos), magpies (Pica spp.), elk (Cervus
canadensis) (Holloran and Anderson 2003, p. 309), and domestic cows
(Bovus spp.) (Coates et al. 2008, pp. 425-426). Ground squirrels
(Spermophilus spp.) also have been identified as nest predators
(Patterson 1952, p. 107; Schroeder et al. 1999, p. 10; Schroder and
Baydack 2001, p. 25), but recent data show that they are physically
incapable of puncturing eggs (Holloran and Anderson 2003, p. 309;
Coates et al. 2008, p. 426; Hagen 2011, p. 97). Several other small
mammals visited sage-grouse nests in Nevada, but none resulted in
predation events (Coates et al. 2008, p. 425).
The most common predators of Gunnison sage-grouse eggs are weasels,
coyotes, and corvids (Young 1994, p. 37). Most raptor predation of
sage-grouse is on juveniles and older age classes (GSRSC 2005, p. 135).
Golden eagles were found to be the dominant raptor species recorded
perching on power poles in Utah in Gunnison sage-grouse habitat
(Prather and Messmer 2009, p. 12), indicating a possible source of
predation. In a study conducted from 2000 to 2009 in the western
portion of the Gunnison Basin, 22 and 40 percent of 111 adult Gunnison
sage-grouse mortalities were the result of avian and mammalian
predation, respectively (Childers 2009, p. 7). Twenty-five and 35
percent of 40 chick mortalities were caused by avian and mammalian
predation, respectively (Childers 2009, p. 7). A causative agent of
mortality was not determined in the remaining mortalities
(approximately one-third of all known mortalities) in the western
portion of the Gunnison Basin from 2000 to 2009 (Childers 2009, p. 7).
Adult male Gunnison and greater sage-grouse are very susceptible to
predation while on the lek (Schroeder et al. 1999, p. 10; Schroeder and
Baydack 2001, p. 25; Hagen 2011, p. 5), presumably because they are
conspicuous while performing their mating displays. Because leks are
attended daily by numerous grouse, predators also may be attracted to
these areas during the breeding season (Braun 1995, p. 2). In a study
of greater sage-grouse mortality causes in Idaho, it was found that,
among males, 83 percent of the mortality was due to predation and 42
percent of those mortalities occurred during the lekking season (March
through June) (Connelly et al. 2000b, p. 228). In the same study, 52
percent of the mortality of adult females was due to predation and 52
percent of those mortalities occurred between March and August, which
includes the nesting and brood-rearing periods (Connelly et al. 2000b,
p. 228).
Predation of adult sage-grouse is low outside the lekking, nesting,
and brood-rearing season (Connelly et al. 2000b, p. 230; Naugle et al.
2004, p. 711; Moynahan et al. 2006, p. 1536; Hagen 2011, p. 97). Adult
female greater sage-grouse are susceptible to predators while on the
nest but mortality rates are low (Hagen 2011, p. 97). Greater sage-
grouse selected nest and brood-rearing sites with lower avian predator
densities than nearby random locations (Dinkins et al. 2012, p. 605).
Hens will abandon their nest when disturbed by predators (Patterson
1952, p. 110), likely reducing this mortality (Hagen 2011, p. 97).
Sage-grouse populations are likely more sensitive to predation upon
females given the highly negative response of Gunnison sage-grouse
population dynamics to adult female reproductive success and chick
mortality (GSRSC, 2005, p. 173).
Estimates of predation rates on juvenile sage-grouse are limited
and variable due to the difficulties in studying this age class
(Aldridge and Boyce 2007, p. 509; Hagen 2011, p. 97). For greater sage-
grouse, chick mortality from predation ranged from 10 to 51 percent in
2002 and 2003 on three study sites in Oregon (Gregg et al. 2003, p. 15;
2003b, p. 17). Mortality due to predation during the first few weeks
after hatching was estimated to be 82 percent (Gregg et al. 2007, p.
648). Survival of juveniles to their first breeding season was
estimated to be low (10 percent). In northwest Colorado, mortality due
to predation was estimated at 26.3 percent in captive reared greater
sage-grouse chicks introduced to the wild (Thompson 2012, pp. 29, 93).
Given the known sources and rates of adult mortality due to predation,
it is reasonable to assume that predation is a contributor to the high
juvenile mortality rates as well (Crawford et al. 2004, p. 4).
Sage-grouse nests are subject to varying levels of predation.
Predation can be total (all eggs destroyed) or partial (one or more
eggs destroyed). However, hens abandon nests in either case (Coates,
2007, p. 26). Over a 3-year period in Oregon, 106 of 124 nests (84
percent) were preyed upon (Gregg et al. 1994, p. 164). Nest predation
rates of 41 percent were reported in one study in Wyoming (Patterson
1952, p. 104), while another study reported a predation rate of 12
percent in Wyoming (Holloran and Anderson 2003, p. 309). Moynahan et
al. (2007, p. 1777) attributed 131 of 258 (54 percent) of nest failures
to predation in Montana. Re-nesting efforts may partially compensate
for the loss of nests due to predation (Schroeder 1997, p. 938), but
re-nesting rates for greater sage-grouse are highly variable (Connelly
et al. 2011b, p. 63). Further, re-nesting rates are low in Gunnison
sage-grouse (Young, 1994, p. 44; Childers, 2009, p. 7), indicating that
re-nesting may not offset losses caused by predation. Loss of breeding
hens and young chicks to predation can influence overall greater and
Gunnison sage-grouse population numbers, as these two groups contribute
most significantly to population productivity (GSRSC, 2005, p. 29,
Baxter et al. 2008, p. 185; Connelly et al., 2011, pp. 64-65).
Nesting success of greater sage-grouse is positively correlated
with the presence of big sagebrush and grass and forb cover (Connelly
et al. 2000, p. 971). Females actively select nest sites with these
qualities (Schroeder and Baydack 2001, p. 25; Hagen et al. 2007, p.
46). Nest predation appears to be related to the amount of herbaceous
cover surrounding the nest (Gregg et al. 1994, p. 164; Braun 1995, pp.
1-2; DeLong et al. 1995, p. 90; Braun 1998; Coggins 1998, p. 30;
Connelly et al. 2000b, p. 975; Schroeder and Baydack 2001, p. 25;
Coates and Delehanty 2008, p. 636). Therefore, loss of nesting cover
from any source (e.g., grazing, fire) has the potential to reduce nest
success and adult hen survival. Also, habitat alteration that reduces
cover for young chicks can increase their rate of predation (Schroeder
and Baydack 2001, p. 27). Conversely, Coates (2007, p. 149) found that
badger predation was facilitated by nest cover as it attracts small
mammals, a badger's primary prey.
In a review of published nesting studies, Connelly et al. (2011,
pp. 63-64) reported that nesting success was greater in unaltered
habitats versus habitats affected by anthropogenic activities. Where
habitat has been altered, it has been shown that the associated influx
of predators can decrease annual recruitment of greater sage-grouse
(Gregg et al. 1994, p. 164;
[[Page 69275]]
DeLong et al. 1995, p. 91; Coates 2007, p. 2;), and the same cause-
effect relationship has been speculated in other cases as well
(Schroeder and Baydack 2001, p. 28; Braun 1995, pp. 1-2; Braun 1998;
Hagen 2011, pp. 97-98). Agricultural development, landscape
fragmentation, and human populations can increase predation pressure on
all life stages of greater sage-grouse by forcing birds to nest in less
suitable or marginal habitats, increasing travel time through altered
habitats where they are vulnerable to predation, and increasing the
diversity and density of predators (see further discussion below)
(Ritchie et al. 1994, p. 125; Schroeder and Baydack 2001, p. 25;
Connelly et al. 2004, p. 7-23; and Summers et al. 2004, p. 523; GSRSC
2005, p.135). We believe the above information for greater sage-grouse
is also applicable to Gunnison sage-grouse since overall behavior and
life-history traits are similar between the two species (Young 1994, p.
4).
In the Strawberry Valley of Utah, a high density of red fox
contributed to historically low survival rates of female (30 percent)
and male (29.7 percent) greater sage-grouse. The authors speculated
that the high density of red foxes were attracted to the area by
Strawberry Reservoir and associated anthropogenic activities (Bambrough
et al. 2000, p. 1). The red fox population has apparently increased
within the Gunnison Basin (BLM, 2009, p. 37), and the species was only
recently observed in habitat within the Monticello, Utah, population
area (UDWR 2011, p. 4). In addition to wild predators, domestic species
including dogs (Canis domesticus) and cats (Felis domesticus) have been
introduced by ranches, farms, and housing developments into greater
sage-grouse habitats (Connelly et al. 2004, p. 12-2).
Raven abundance has increased as much as 1,500 percent in some
areas of western North America since the 1960s (Coates 2007, p. 5).
Breeding bird survey trends from 1966 to 2007 indicate increases
throughout Colorado and Utah (USGS, 2009, pp. 1-2). The presence of
ravens was negatively associated with greater sage-grouse nest and
brood success in western Wyoming (Bui 2009, p. 27). It was suggested
that raven numbers have increased in the Pi[ntilde]on Mesa population,
though data have not been collected to verify this (CDOW 2009b, p.
110). Raven numbers in the Monticello population area remain high (UDWR
2011, p. 4).
Local attraction of ravens to nesting hens may be facilitated by
loss and fragmentation of native shrublands, which increases the
exposure of nests to predators (Aldridge and Boyce 2007, p. 522; Bui
2009, p. 32; Howe et al. 2014, p. 41-44). Human-made structures in the
environment increase the effect of raven predation, particularly in low
canopy cover areas, by providing ravens with perches (Braun 1998, pp.
145-146; Coates 2007, p. 155; Bui 2009, p. 2; Howe et al. 2014, p. 41-
44) (also see discussion under Factor A above). Reduction in patch size
and diversity of sagebrush habitat, as well as the construction of
fences, powerlines, and other infrastructure, also are likely to
encourage the presence of the common raven (Coates et al. 2008, p. 426;
Bui 2009, p. 4; Howe et al. 2014, p. 44). For example, raven counts
have increased by approximately 200 percent along the Falcon-Gondor
transmission line corridor in Nevada (Atamian et al. 2007, p. 2).
Ravens contributed to lek disturbance events in the areas surrounding
the transmission line (Atamian et al. 2007, p. 2), but as a cause of
decline in surrounding sage-grouse population numbers, this could not
be separated from other potential impacts, such as West Nile virus.
Holloran (2005, p. 58) attributed increased sage-grouse nest predation
to high corvid abundance, which resulted from anthropogenic food and
perching subsidies in areas of natural gas development in western
Wyoming. Bui (2009, p. 31) also found that ravens used road networks
associated with oil fields in the same Wyoming location for foraging
activities. Holmes (2009, pp. 2-4) also found that common raven
abundance increased in association with oil and gas development in
southwestern Wyoming.
Raven abundance was strongly associated with sage-grouse nest
failure in northeastern Nevada, with resultant negative effects on
sage-grouse reproduction (Coates 2007, p. 130). The presence of high
numbers of predators within a sage-grouse nesting area may negatively
affect sage-grouse productivity without causing direct mortality.
Increased raven abundance was associated with a reduction in the time
spent off the nest by female sage-grouse, thereby potentially
compromising their ability to secure sufficient nutrition to complete
the incubation period (Coates 2007, pp. 85-98). Another model utilized
known raven nest locations and found a 31 percent decrease in the odds
of nesting by ravens for every 1-km increase in distance from a
transmission line (Howe et al. 2014), indicating that the presence of
transmission lines may increase the presence of and risk of predation
by ravens in sage-grouse habitat.
As more suitable grouse habitat is converted to exurban
development, agriculture, or other non-sagebrush habitat types, grouse
nesting and brood-rearing become increasingly spatially restricted (Bui
2009, p. 32). Future human population growth and associated development
and infrastructure will likely further restrict nesting habitat within
the species' range. Additionally, Gunnison sage-grouse have been shown
to avoid residential development and infrastructure in some areas,
resulting in functional habitat loss (Aldridge et al. 2012, p. 402). Of
99 nest sites studied in the western portion of the Gunnison Basin
population, 69 (approximately 70 percent) occurred within 13 percent of
the available habitat (Aldridge et al. 2012, p. 400). Unnaturally high
nest densities, which result from habitat fragmentation or disturbance
associated with the presence of edges, fencerows, or trails, may
increase predation rates by making foraging easier for predators
(Holloran 2005, p. C37). Increased nest density could negatively
influence the probability of a successful hatch (Holloran and Anderson,
2005, p. 748).
The influence of the human footprint in sagebrush ecosystems may be
underestimated (Leu and Hanser 2011, pp. 270-271) since it is uncertain
how much more habitat sage-grouse (a large landscape-scale species)
need for persistence in increasingly fragmented landscapes (Connelly et
al. 2011a, pp. 80-82). Therefore, the influence of ravens and other
predators associated with human activities may be underestimated. In
addition, nest predation may be higher, more variable, and have a
greater impact on the small, fragmented Gunnison sage-grouse
populations, particularly the six smallest populations (GSRSC 2005, p.
134).
Except for the few studies presented here, data that link Gunnison
sage-grouse population numbers and predator abundance are limited.
Still, in at least the six smaller populations, the best available
information suggests that predation may be limiting Gunnison sage-
grouse survival and persistence. The lack of recruitment in the San
Miguel population may be associated with predation (CDOW 2009b, p. 31;
Davis 2012, p. 162). In this area, six of 12 observed nests were
destroyed by predation. None of the chicks from the remaining
successful nests survived beyond two weeks. Those observations are in
contrast to the Gunnison Basin where approximately 20 percent of radio-
marked chicks survived their first year during that period. Further,
trends in lek count and other data indicate there has been no
recruitment of young into the San Miguel population since
[[Page 69276]]
around 2005. The CPW suspects these trends are most likely due to
predation (CDOW 2009b, p. 30-31; Davis 2012, pp. 37, 79). The other
five satellite populations are smaller than the San Miguel population;
therefore, it is reasonable to expect that predation may be limiting
those populations as well.
Actions To Address Predation
Due to low population numbers and the potential impact of
predation, a predator control program initiated by CPW occurred between
March 2011 and June 2012 in the Miramonte subpopulation area of the San
Miguel population to evaluate the effects of predator removal on
Gunnison sage-grouse juvenile recruitment in the subpopulation (CPW
2012b, pp. 8-10). Over the two-year period, the United States
Department of Agriculture Animal and Plant Health Inspection Service
removed 155 coyotes, 101 corvids, two bobcats, eight badgers, two
raccoons, and three red foxes. Radio-marked hens, nest success, and
chick survival were monitored during this time, and results were
compared to baseline data collected for the same area from 2007 to
2010. Prior to predator control, of eight marked chicks, no individuals
survived to 3 months. From 2011 through August of 2012, during which
predator control occurred, of 10 marked chicks, four (40 percent)
chicks survived to three months, and two (20 percent) survived at least
one year. The study did not compare chick survival rates to non-
predator removal areas, so it is unknown whether the apparent increase
in chick survival was due to predator control or other environmental
factors (e.g., weather, habitat conditions, etc.).
Predator removal efforts have sometimes shown short-term gains that
may benefit fall populations, but not breeding population sizes (Cote
and Sutherland 1997, p. 402; Hagen 2011, pp. 98-99; Leu and Hanser
2011, p. 270). Predator removal may have greater benefits in areas with
low habitat quality, but predator numbers quickly rebound without
continual control (Hagen 2011, p. 99). Red fox removal in Utah appeared
to increase adult greater sage-grouse survival and productivity, but
the study did not compare these rates against other nonremoval areas,
so inferences are limited (Hagen 2011, p. 98).
Coyote control efforts failed to have an effect on greater sage-
grouse nesting success in southwestern Wyoming (Slater 2003, p. 133).
However, coyotes may not be an important predator of sage-grouse. In a
coyote prey base analysis, sage-grouse and bird egg shells made up a
very small percentage (0.4-2.4 percent) of analyzed scat samples
(Johnson and Hansen 1979, p. 954). Additionally, coyote removal can
have unintended consequences resulting in the release of smaller
predators, like the red fox, many of which may have more negative
impacts on sage-grouse (Mezquida et al. 2006, p. 752).
Removal of ravens from an area in northeastern Nevada caused only
short-term reductions in raven populations (less than 1 year), as
apparently transient birds from neighboring sites repopulated the
removal area (Coates 2007, p. 151). Additionally, badger predation
appeared to partially compensate for decreases due to raven removal
(Coates 2007, p. 152). In their review of literature regarding
predation, Connelly et al. (2004, p. 10-1) noted that only two of nine
studies examining survival and nest success indicated that predation
had limited a sage-grouse population by decreasing nest success, and
both studies indicated low nest success due to predation was ultimately
related to poor nesting habitat. It has been suggested that removal of
anthropogenic ``subsidies'' (e.g., landfills, tall structures) may be
an important step to reducing the presence of sage-grouse predators
(Bui 2009, pp. 36-37). Leu and Hanser (2011, p. 270) also argue that
reducing the effects of predation on sage-grouse can only be
effectively addressed by precluding these features.
In 1999, property was transferred from the BLM to Gunnison County
for the purposes of the Gunnison County Landfill. This conveyance
required implementation of a mitigation plan for potential impacts to
Gunnison sage-grouse, including establishment of a mitigation fund
known as the Gunnison Sage-grouse Conservation Trust. To date, over
$250,000 has been allocated from the trust fund for Gunnison sage-
grouse projects in occupied habitat in Gunnison County. Projects
include, but are not limited to, habitat improvements, conservation
easements, road closures, and outreach and education (Gunnison County
2013a, pp. 147-150). Gunnison County has actively controlled ravens at
the Gunnison County Landfill since 2003. Between 200 and 250 ravens are
removed annually within the landfill boundaries. Further efforts to
control ravens in the Gunnison Basin are under consideration by the
county and the Gunnison Basin Sage-grouse Strategic Committee (Gunnison
County 2013a, p. 132). The effects of these control efforts on Gunnison
sage-grouse survival have not been studied.
Gunnison County and CPW have jointly funded an ongoing study (Magee
2013, pers. comm.) of the distribution and abundance of ravens and
crows (corvids), which may help inform managers of the potential
influence of these species in the Gunnison Basin. Of twelve survey
sites in the Gunnison Basin, the site most used by ravens was the
Gunnison County Landfill. Preliminary distribution and abundance data
indicate that a large number of ravens are utilizing the landfill as
their primary food source (Magee 2013, pers. comm.). Additional
information from surveys during spring and early summer of 2014 may
provide information on raven use of sagebrush habitats during the sage-
grouse breeding and nesting season when Gunnison sage-grouse are more
vulnerable to predation. Evaluating raven predation on Gunnison sage-
grouse was not an objective of this study. However, preliminary data on
raven abundance, spatial and temporal distribution, and movements
suggest that ravens are not preying on Gunnison sage-grouse as primary
food source in the Gunnison Basin. Planned spring and early summer
surveys may indicate otherwise, but the results of these surveys were
not available at the time of drafting of this final rule.
Summary of Predation
Due to the extent of human influence and alteration of habitat
across its range, Gunnison sage-grouse may be increasingly subject to
levels and impacts of predation that would not normally occur in the
historically contiguous, intact sagebrush habitats, or in larger, more
resilient populations. Gunnison sage-grouse are adapted to minimize
predation through cryptic plumage and behavior, however predation is
strongly influenced by anthropogenic factors on the landscape, and
human presence on the landscape will continue to increase. The impacts
of predation on greater sage-grouse can increase where habitat quality
has been compromised by anthropogenic activities (exurban development,
road development, powerlines, etc.) (e.g., Coates 2007, pp. 154, 155;
Bui 2009, p. 16; Hagen 2011, p. 100; Howe et al. 2014, p. 41-44).
Landscape fragmentation and habitat decline associated with human
populations have the potential to increase predator populations through
increasing the ease of securing prey and subsidizing food sources and
nest or den substrate for predators. Consequently, otherwise suitable
habitat may change into a habitat sink (habitat in which reproduction
is insufficient to balance
[[Page 69277]]
mortality) for grouse populations (Aldridge and Boyce 2007, p. 517).
Anthropogenic influences on sagebrush habitats that increase
suitability for ravens may also limit sage-grouse populations (Bui
2009, p. 32). Current land-use practices in the Intermountain West
favor high predator (in particular, raven) abundance relative to
historical numbers (Coates et al. 2008, p. 426). The interaction
between changes in habitat and predation may have substantial effects
to sage-grouse at the landscape level (Coates 2007, pp. 3-5; Howe et
al. 2014, p. 41-44).
Research and data linking predation to Gunnison sage-grouse
abundance and viability are limited. However, the studies presented
above suggest that, particularly in areas of intensive habitat
alteration and fragmentation and in smaller less resilient populations,
sage-grouse productivity and, potentially, population viability could
be negatively affected by predation. Since the Gunnison and greater
sage-grouse have similar behavior and life-history traits, it is
reasonable to assume that predator impacts on Gunnison sage-grouse are
similar to those documented in greater sage-grouse. As more habitats
are altered or lost due to human development, including dispersed
development, we expect predators to spread and increase in numbers into
the future, thereby increasing the risk of predation. Ongoing effects
from predation are likely greater in the smaller satellite populations,
and will likely increase if these populations continue declining in
abundance. Therefore, the best available information indicates that, as
we stated in our proposed rule, predation is a current and future
threat to the species, particularly in the satellite populations. While
predation likely acts as a threat in localized areas across the range
of the species, the stability of the Gunnison Basin population over the
last 19 years indicates that predation is not having a significant
impact on that population. We believe, however, that the effects of
predation are more pronounced in the satellite populations. Given the
stability of the Gunnison Basin population, we do not believe that the
magnitude of this threat is significant at the rangewide level.
Summary of Factor C
We have reviewed the available information on the effects of
disease and predation on the long-term persistence of the Gunnison
sage-grouse. The only disease that is known to be a threat to the
survival of the Gunnison sage-grouse is West Nile virus. This virus is
distributed throughout most of the species' range. However, despite its
near 100 percent lethality, disease occurrence is sporadic in other
taxa across the species' range and has not yet been detected in
Gunnison sage-grouse. While we have no evidence of West Nile virus
acting on Gunnison sage-grouse individuals or populations, because of
its presence within the species' range, its lethality to sage-grouse,
and the continued development of anthropogenic water sources in the
area that support mosquito vector populations, the virus is a future
threat to the species. We anticipate that West Nile virus will persist
within the range of Gunnison sage-grouse indefinitely and that the
threat it presents will be exacerbated by any factor (e.g., drought,
climate change) that increases ambient temperatures and the presence of
the vector on the landscape.
The best available information shows that existing and future
habitat decline, and fragmentation in particular, will increase the
effects of predation on this species, particularly in the six smaller
populations, resulting in a reduction in sage-grouse productivity and
abundance in the future.
We evaluated the best available scientific information regarding
disease and predation and their effects on the Gunnison sage-grouse.
Based on the information available, we have determined that predation
and disease are threats to the species throughout its range at the
present time and are likely to increase in the future. In particular,
West Nile virus poses a substantial threat to Gunnison sage-grouse
rangewide in the foreseeable future.
D. The Inadequacy of Existing Regulatory Mechanisms
Under this factor, we examine whether threats to the Gunnison sage-
grouse are adequately addressed by existing regulatory mechanisms.
Existing regulatory mechanisms that can provide some protection for
Gunnison sage-grouse include: (1) Local land use laws, regulations and
ordinances; (2) State laws and regulations; and (3) Federal laws and
regulations. Regulatory mechanisms, if they exist, may preclude the
need for listing if such mechanisms adequately address the threat to
the species such that listing is not warranted. Conversely, threats to
a species may be exacerbated when not addressed at all by existing
regulatory mechanisms, or if the existing mechanisms are not adequately
implemented or enforced.
Multiple partners, including private citizens, nongovernmental
organizations, Tribes, Counties, States, and Federal agencies, are
engaged in conservation efforts across the range of Gunnison sage-
grouse. Conservation efforts by these parties that are voluntary or are
not enforceable, however, including conservation strategies and
guidance, are typically not regulatory mechanisms. Non-regulatory
conservation efforts that address habitat related issues, such as the
Rangewide Conservation Plan, the Colorado CCAA and the Gunnison Basin
CCA, are described and evaluated under Factor A, and other non-
regulatory conservation efforts are described and assessed under
relevant threat sections. In this section, pursuant to Factor D, we
review and evaluate only regulatory mechanisms undertaken by local,
State, and Federal entities designed to reduce or remove threats to
Gunnison sage-grouse and its habitat.
Local Laws and Regulations
Approximately 43 percent of Gunnison sage-grouse rangewide occupied
habitat is privately owned (Table 1), and local laws and regulations
are most applicable in those areas. Local laws and regulations vary
widely by county across Gunnison sage-grouse range. Below we first
broadly address general county regulations that have the potential to
affect Gunnison sage-grouse and its habitat and then move on to local
laws and regulations that specifically address Gunnison sage-grouse.
Under state law, all county governments have general authority to
regulate land use development in their jurisdictions through the
implementation of comprehensive or master plans, zoning, and
subdivision planning (Colo. Rev. Stat. Sec. 30-28-101 et seq.; Utah
2011, entire), and to protect wildlife habitat through enforcement of
wildlife-related regulations or requirements (Colo. Rev. Stat. Sec.
24-65.1-104; Utah Code Sec. 17-27a-403). Local laws and regulations
enacted pursuant to this authority may benefit Gunnison sage-grouse
depending on the regulations adopted in a particular county and the
degree to which threats to Gunnison sage-grouse and its habitat are
considered and addressed in these local regulations.
By statute, the State of Colorado grants Colorado counties broad
authority for planning and regulation of land use and development in
their respective jurisdictions (Colo. Rev. Stat. Sec. 30-28-101 et.
seq.). This law provides that whenever local land use regulations
impose higher standards than other statutes, the provisions of the
regulations made under local authority (i.e., county planning) shall
apply (Colo. Rev. Stat. Sec. 30-28-123). Furthermore, Colorado law
authorizes local
[[Page 69278]]
governments to plan for and regulate land uses in order to protect
significant wildlife habitat and species (Colo. Rev. Stat. Sec. 30-29-
104).
In our proposed rule, we reported that Colorado law exempts parcels
of land that are 35 acres or larger from county land use regulations
(78 FR 2523). This is only partially correct. Under Colorado law, a
county does not have authority to regulate the subdivision of land that
creates parcels that are each 35 acres or larger (``plus-35 acre
parcels'') (Colo. Rev. Stat. Sec. 30-28-101(10)(b)). However, Colorado
counties retain authority to regulate the actual use and development of
plus-35 acre parcels (for example, home, road, or infrastructure
development). All Colorado counties in the occupied range of Gunnison
sage-grouse have land use regulations that apply to development of
plus-35 acre parcels (Delta County 2013-R-025; Dolores County policy on
subdivisions exemptions; Gunnison County 95-34; Mesa County 31;
Montrose County 45-2012, 02-2013, 24-2013, 14-2006; Ouray County 2013-
022; Saguache County 2013-LU-11; San Juan County Utah Statute Summary;
San Miguel Article 1). Similarly, the State of Utah grants County
governments, including San Juan County, which encompasses the
Monticello population of Gunnison sage-grouse, authority to regulate
and control property (i.e., zoning) and development (Utah 2011,
entire).
County or city ordinances in San Juan County, Utah, that address
agricultural lands, transportation, and zoning for various types of
land uses have the potential to affect sage-grouse habitat, behavior,
and abundance. Similarly, general, non-sage-grouse specific local land
use codes and permitting requirements in the Colorado portion of the
species' range can affect development in occupied habitat and thus have
implications for the species and its habitat. We do not, however, have
sufficient information about implementation of general local land use
laws and regulations to determine what uses, if any, have been modified
pursuant to these general authorities to avoid or lessen impacts to
Gunnison sage-grouse. Therefore, we are unable to conclude that such
general county land use codes and regulations within Gunnison sage-
grouse occupied habitat constitute adequate regulatory mechanisms to
reduce the threats to the species. (Local land use regulations specific
to Gunnison sage-grouse are discussed individually and separately
below.)
Many Colorado counties within Gunnison sage-grouse range have
requirements for County review of development proposals, which may
include generic ``1041'' wildlife habitat regulations, requiring review
and/or coordination with CPW/UDWR for new subdivision and development
requests in sensitive wildlife habitat (Delta County 2011-R-054. 2012-
R-044, 2013-R-025; Delta County 2011-R-054; Dolores County land use
regulations; Mesa County 7.6.4; Ouray County 6, 25, and site
development permit; Saguache County Article XX). However, we do not
have sufficient information to determine whether and how these general
wildlife habitat regulations have been applied to Gunnison sage-grouse
habitat, what recommendations may have been made by CPW/UDWR regarding
the avoidance of impacts to Gunnison sage-grouse under these non-sage-
grouse specific regulations, and how or if the counties incorporated
any such recommendations in their land use authorization. Therefore, we
cannot conclude that the generic county requirements to consult with
state wildlife agencies for actions that occur within sensitive
wildlife habitat constitute adequate regulatory mechanisms to reduce
the threats to the species. (Again, wildlife habitat regulations
specific to Gunnison sage-grouse are discussed separately below.)
Several counties without specific land use regulations directed at
Gunnison sage-grouse habitat conservation do have regulations that
contain restrictions that may benefit the species. These measures may
include control of dogs, seasonal road closures, or requirements for
clustering housing units within subdivisions. Specifically, San Juan
County, Utah, and Gunnison, San Miguel, Mesa, and Montrose Counties,
Colorado include regulations to control dogs from roaming freely and
Dolores, Gunnison, Mesa, San Juan, and San Miguel Counties have
regulations that apply to road closures (CPW 2014g; Appendix A).
Counties within Gunnison sage-grouse range with regulations or
policies that include conservation measures or considerations
specifically targeted at Gunnison sage-grouse and its habitat include
Dolores, Gunnison, Montrose, Ouray, and San Miguel Counties, Colorado
(Dolores County 05-13-04; Gunnison County 2013a, pp. 33-57; Gunnison
County 2013b, p. 11; Gunnison County 11-106, 07-17 and 2013-23;
Gunnison County 2014-24; Montrose County 2013, entire; Montrose County
39-2013; Ouray County 2013-022; San Miguel County land use code, 2-16,
5-407, 5-26; San Miguel County Wright's Mesa Zone Districts), as
described below. We anticipate that land use regulations designed
specifically for Gunnison sage-grouse will typically be more effective
in conserving the species and its habitat than the standard regulations
described above that do not address the species specifically.
Gunnison County Sage-Grouse Regulations (Gunnison Basin Population)
The Gunnison Basin population is located in Gunnison and Saguache
County, Colorado. Gunnison County has adopted specific regulations to
further the conservation of the Gunnison sage-grouse and its habitat
(Gunnison County Land Use Resolution (LUR) Sec. 11.106 including
amendments 07-17 and 2013-23). Approximately 79 percent of private
lands in occupied habitat in the Gunnison Basin population is in
Gunnison County, and is thereby subject to those regulations. The
remaining 21 percent of private lands in the Gunnison Basin population
is in Saguache County, which does not currently have similar species-
specific regulations in place, although Saguache County is working to
develop species-specific criteria (CPW 2014g, Attachment 3, Appendix
A).
Gunnison County's Land Use Resolution (LUR) 11.106 was adopted in
1977 and broadly provides for the regulation of land uses in sensitive
wildlife habitat areas. In 2007, Gunnison County Board of County
Commissioners approved Resolution Number 07-17, which amended LUR
11.106, to create a review process and protective standards specific to
Gunnison sage-grouse. In 2013, Gunnison County further amended LUR
Sec. 11.106 to incorporate use of the Gunnison Basin Sage Grouse
Habitat Prioritization Tool, a GIS model developed by the Gunnison
Basin Sage-grouse Strategic Committee in 2012 that first stratifies or
values Gunnison sage-grouse habitat (largely based on distances to
leks) and then discounts the value of the habitat based on soils, and
on distance to developed areas including structures, roads, and power
lines. This process stratifies occupied habitat in the Gunnison Basin
into three types (Gunnison County 2013a, Appendix G; see detailed
description under Local Laws and Regulations, Gunnison County). Tier 1
habitat includes important seasonal habitats and is considered the
highest value for the species; Tier 2 habitat includes the remainder of
occupied habitat in the Gunnison Basin that is closer to structures,
roads, and power lines, and is generally of lower value to the species.
Occupied habitat that does not stratify into Tier 1 or Tier 2 is not
considered Gunnison sage-grouse
[[Page 69279]]
habitat under Gunnison County's sage-grouse regulations. CPW telemetry
data from 2004 to 2010 for approximately 500 collared Gunnison sage-
grouse in the Gunnison Basin showed that, of 10,140 radio locations in
Saguache and Gunnison County, approximately 79.63 percent (8,074) and
15.65 percent (1,587) points occurred in Tier 1 habitat and Tier 2
habitats, respectively (including all occupied habitat in the Gunnison
Basin regardless of ownership) (Gunnison County 2013b, p. 25; Gunnison
County 2013d, p. 1). This indicates a preference for modeled Tier 1
habitats by the Gunnison Basin birds and supports the model's
reliability.
As amended, Gunnison County LUR Sec. 11.106 requires the County to
review applications for land use change permits, building permits,
individual sewage disposal system permits, Gunnison County access
permits, and Gunnison County Reclamation permits (Gunnison County
Public Works Department 2014a, 2014b; subject to some exceptions)
specifically for potential impacts to Gunnison sage-grouse and occupied
habitat. If the activity to be permitted is located wholly or partially
in Gunnison sage-grouse habitat identified pursuant to the Habitat
Prioritization Tool, then the County performs a site-specific analysis
and works with the applicant to ensure that the project meets the
County's sage-grouse specific and other wildlife protective standards
for such development (LUR Sec. 11.106.G-11.106.J). In general, these
standards direct that covered land use activities and projects be
designed to avoid, minimize, and/or mitigate impacts on the species and
its habitat. According to Gunnison County, standard avoidance and
minimization measures included in permits subject to LUR Sec. 11.106
include restrictions on pets and animals and on the siting and timing
of construction, adjustment of building envelopes, and other
recommendations (Gunnison County 2013a, pp. 24-31). Mitigation
techniques as defined and used by Gunnison County include visual and
sound buffers, limitation of human activities during sensitive time
periods, and controls on the location of development. Gunnison County's
use of the term ``mitigation'' thus differs from the Service's
definition of this term, which is the full suite of activities to
avoid, minimize, and compensate for adverse impacts to sage-grouse and
sage-grouse habitat.
From July 2006 through September 2014, Gunnison County reviewed 461
projects under Sec. 11.106 for impacts to Gunnison sage-grouse.
Gunnison County reports that, to date, the majority of development
projects have been located within existing areas of development,
including outbuildings or additions to buildings. According to the
County seventy-one (15.4 percent) of the projects reviewed involved
development within 1 km (0.6 mi) of a lek (CPW 2014g, Attachment 3, p.
27). Implementation of the County regulations likely reduced impacts
from these projects, but did not fully compensate for disturbance or
lost habitat.
Pursuant to Gunnison County Resolution No. 95-34, adopted on June
6, 1995, ``individual parcels of land greater than 35 acres in size are
subject to the same county review and regulatory processes as
individual parcels less than 35 acres in size except, as is generally
provided in current state statute, for the act of subdividing such
parcels into resultant parcels all of which are 35 acres or greater in
size'' (Gunnison County 2013a, pp. 34-35). As a result, development on
parcels that are 35 acres or larger requires one or more of the County
permits identified above and are subject to review and regulation under
LUR Sec. 11.106.
Gunnison County reports that five separate developments involving
35-acre or greater parcels (``plus-35 acre'') have occurred in the
County since 2003. This included a total of about 2,700 acres divided
into 75 parcels, with portions occurring in occupied habitat for
Gunnison sage-grouse. Two of the five projects were reviewed by
Gunnison County under LUR Sec. 11.106 for Gunnison sage-grouse
concerns and included permit conditions to avoid and minimize potential
impacts from their development. The County reports that the other three
projects did not occur in Gunnison sage-grouse habitats. The Ohio Creek
area, which has experienced the greatest concentration of plus-35 acre
development in the county since lek counts were standardized in 1996,
has had increasing numbers of Gunnison sage-grouse since that time
(based on increased high male counts at the Ohio Creek lek) (Gunnison
County 2013a, pp. 35-37).
Recently, Gunnison County has started requiring monetary
compensation for reclamation of habitats disturbed in Tier 1 and Tier 2
Gunnison sage-grouse habitat (Gunnison County Public Works Department
2014a, 2014b; subject to some exceptions). This is a recently enacted
regulation for which we have little more information that what is
presented here. Additional regulatory measures implemented by Gunnison
County in coordination with State and Federal agencies include: closing
of shed antler collection in the Gunnison Basin by the Colorado
Wildlife Commission due to its disturbance of Gunnison sage-grouse
during the early breeding season, and a BLM/USFS/Gunnison County/CPW
collective effort to implement and enforce road closures during the
early breeding season (March 15 to May 15) (see Roads for more
details). These regulatory efforts have provided a benefit to Gunnison
sage-grouse during the breeding period.
We commend Gunnison County for the regulatory measures (and other
actions it has taken, as described in the Factor A discussion above and
elsewhere in this final rule), to conserve Gunnison sage-grouse and its
habitat. The County regulations have helped to reduce some of the
negative effects of human development and infrastructure on the species
and its habitat. However, Gunnison County's current Gunnison sage-
grouse related regulations do not prevent human development in Gunnison
sage-grouse habitat nor do they prevent additional habitat loss and
fragmentation that occurs as a result. Further, they do not address or
require offsetting or mitigation for the habitat loss and fragmentation
that cannot be avoided and that occurs as a result of permitted
development in the species' habitat. Gunnison County's sage-grouse
regulations have not, therefore, sufficiently or adequately reduced
this threat, which is the primary concern related to human development
(see Factor A, Residential Development).
San Miguel County Gunnison Sage-Grouse Regulations (San Miguel
Population)
In 2005, San Miguel County amended its Land Use Codes to require
consideration and implementation, to the extent possible, of
conservation measures recommended in the 2005 RCP (GSRSC 2005, entire)
for the Gunnison sage-grouse when considering land use activities and
development located within its habitat (San Miguel County 2005). More
specifically, under its Land Use Code, the County has specific
requirements that apply when there is a request for a special use
permit (such as for oil and gas facilities or wind turbines) in
occupied habitat. Special use permits are not, however, typically
required for residential development projects, which limits the
County's involvement in review of projects adversely affecting Gunnison
sage-grouse and their habitat. In addition, when the County receives an
application for a special use permit for activities in sage-grouse
habitat, it only solicits recommended conservation measures from the
CPW and a local
[[Page 69280]]
Gunnison sage-grouse working group, and does not require implementation
of the recommended conservation measures. As a result, implementation
of recommended conservation measures is dependent on negotiations
between the County and the applicant.
Some positive measures (e.g., locating a special use activity
outside grouse habitat, establishing a 324-ha (800-ac) conservation
easement; implementing speed limits to reduce likelihood of bird/
vehicle collisions) have been implemented as a result of this process.
Most measures that result from discussions with applicants, however,
result in measures that may minimize, but do not prevent, or mitigate
for impacts (Henderson 2010, pers. comm.). In addition, as noted above,
residential development proposals typically do not require a special
use permit so are not subject to this review and negotiation process.
San Miguel County also has regulations relating to the Wrights Mesa
Zone Districts that restrict fence building, sagebrush removal,
powerlines, housing, and roads within 0.6 miles of a lek (San Miguel
County 2010, entire). In addition, San Miguel County hired a Gunnison
Sage-grouse Coordinator for the San Miguel Basin population in March
2006 to implement the regulatory process.
The San Miguel County Land Use Codes provide some conservation
benefit to the species by encouraging landowners to voluntarily
minimize impacts of residential development in grouse habitat where the
County has authority to do so (with special use permits). The County's
regulations do not prevent human disturbance in occupied habitat or
address or require offsetting or mitigation for habitat loss and
fragmentation resulting from such disturbance. As a result, we find
that San Miguel County's regulations do not adequately address the
threat of habitat loss, degradation and fragmentation which is the
primary concern related to human development (see Factor A, Residential
Development).
Dolores, Ouray, and Montrose County Sage-Grouse Regulations (San Miguel
and Cerro Summit-Cimarron-Sims Mesa Populations)
Ouray County adopted a resolution (Resolution Number 2013-022) on
May 28, 2013, directed at protecting Gunnison sage-grouse breeding and
brood-rearing habitat from land use activities including construction
and motor vehicle use. The resolution provides that seasonal
restrictions (March 15 until May 15) be implemented for roads (not
belonging to adjacent property owners or their guests) and appropriate
terms and conditions be applied during this same time period at
construction sites within 0.6 miles of a lek to minimize and avoid
impacts on breeding and brood-rearing habitat (Ouray County 2013,
entire). The restrictions do not specify what avoidance or minimization
will occur with development permits in these areas.
On November 4, 2013, Montrose County adopted special regulations
(``1041 regulations'' 39-2013) that are intended to avoid and minimize
impacts from land use activities on Gunnison sage-grouse and occupied
habitat, similar to the approach adopted by Gunnison County. Building
permits are required for construction within 0.6 miles of an active
lek, and land use projects or permitting in occupied habitat will
require conservation actions to avoid or minimize impacts on Gunnison
sage-grouse (Montrose County 2013, entire).
On May 20, 2013 Dolores County clarified what planning and
regulatory means are available for local efforts in preservation of
Gunnison sage-grouse (Dolores County Resolution 05-13-04). The
resolution highlights coordination with CPW (and other agencies) to
review the impacts to wildlife from any change of use application
submitted to the County. It also highlights regular coordination with
both the BLM and the U.S. Forest Service.
While these three recently enacted county regulations likely
provide some conservation benefits to the species, none of them provide
the requisite certainty that they will be effective in ameliorating the
threat human development poses to the species and its habitat. For
example, the Ouray County regulations do not specify what terms or
conditions will be required for construction in occupied habitat, and
neither the Montrose nor Dolores County regulations specify how
mitigation will occur where effects cannot be avoided. None of these
county regulations prevent human development in occupied habitat and
the additional habitat loss and fragmentation that occurs as a result,
or address or require offsetting or mitigation of habitat loss for the
species, which is the primary concern related to human development (see
Factor A, Residential Development). As a result, none of these local
land regulations eliminate or adequately reduce the impact of human
development on Gunnison sage-grouse and their habitat.
Summary of Local Laws and Regulations
We commend the efforts that local governments have made to date
(those regulations not yet completed are not included) to enact and
strengthen local regulatory protections for Gunnison sage-grouse.
Existing local laws and regulations are helping and will continue to
help to reduce the negative effects of human development and
infrastructure on the species. Continuation, enhancement, and expansion
of these efforts across the species' range will likely be necessary for
conservation of the species. Nevertheless, current local laws and
regulations do not fully address the full scope of threats to the
species (Factors A through C and E), including habitat loss due to
residential and human development (see Residential Development). The
permanent loss, and associated fragmentation and degradation, of
sagebrush habitat are considered the greatest threat to Gunnison sage-
grouse (GSRSC 2005, p. 2). Residential development is likely
contributing to habitat loss and degradation throughout the range of
Gunnison sage-grouse. Future development, especially in areas of
important seasonal habitats, is a concern throughout the range,
including in the Gunnison Basin, where we believe that the level of
impact from residential development will increase in the future (Factor
A). For the reasons described above, existing local regulations and
laws do not fully address this threat. Likewise, existing local
regulations and laws do not address other substantial threats to the
species, including small population size and structure (Factor E),
drought (Factor E); or disease (Factor C).
State Laws and Regulations
Colorado and Utah State laws and regulations may influence Gunnison
sage-grouse conservation by providing specific authority for sage-
grouse conservation over lands that are directly owned by the States.
As described in more detail below, the States also have broad authority
to regulate and protect wildlife on all lands within their borders, and
State laws provide mechanisms for indirect conservation through
regulation of threats to the species (e.g., noxious weeds). In the
previous section, we described the authorities granted by Colorado and
Utah to local and county governments in regulating land use development
within their respective jurisdictions to conserve wildlife, including
the Gunnison sage-grouse.
[[Page 69281]]
Colorado Revised Statutes (C.R.S.) section 33-1-104 gives the CPW
Board responsibility for the management and conservation of wildlife
resources within State borders. The CPW, which operates under the
direction of the CPW Board, is required by statute to provide counties
with information on ``significant wildlife habitat,'' and provide
technical assistance in establishing guidelines for designating and
administering such areas, if asked (C.R.S. Sec. 24-65.1-302). The CPW
Board also has authority to regulate possession of the Gunnison sage-
grouse, set hunting seasons, and issue citations for poaching (C.R.S
Sec. 33-1-106). These authorities, as implemented by the CPW Board,
provide individual Gunnison sage-grouse with protection from direct
mortality from hunting, as described below.
The Wildlife Resources Code of Utah (Utah Code Annotated Title 23)
provides UDWR with the powers, duties, rights, and responsibilities to
protect, propagate, manage, conserve, and distribute wildlife
throughout the State (Utah Code Ann. Sec. 23-14-1). Section 23-13-3 of
the Code declares that wildlife existing within the State, not held by
private ownership and legally acquired, is property of the State.
Section 23-14-18 authorizes the Utah Wildlife Board to prescribe rules
and regulations for the taking and/or possession of protected wildlife,
including Gunnison sage-grouse. These authorities provide adequate
protection to individual Gunnison sage-grouse from direct mortality
from hunting, as described below.
Gunnison sage-grouse are managed by CPW and UDWR on all lands
within each State as resident native game birds. In both States this
classification allows the direct human taking of the bird during
hunting seasons authorized and conducted under State laws and
regulations. In 2000, CPW closed the hunting season for Gunnison sage-
grouse in the Gunnison Basin, the only area then open to hunting for
the species. The hunting season for Gunnison sage-grouse in Utah has
been closed since 1989 according to GSRSC (2005, p. 82), or as early as
the mid-1970's according to SJCWG (2000, p. 11). The Gunnison sage-
grouse is listed as a species of special concern in Colorado, as a
sensitive species in Utah, and as a Tier I species under the Utah
Wildlife Action Plan, providing heightened priority for management
(CDOW 2009b, p. 40; UDWR 2009, p. 9). Hunting and other State
regulations that deal with issues such as harassment provide adequate
protection for individual birds (see discussion under Factor B), but do
not protect the habitat or address other substantial threats such as
drought, climate change, or disease.
In 2009, the Colorado Oil and Gas Conservation Commission (COGCC),
which is the entity responsible for permitting oil and gas well
development in Colorado, adopted new rules addressing the impact of oil
and gas development on wildlife resources (COGCC as amended 2014,
entire). These COGCC rules require that permittees and operators on all
lands within the state of Colorado determine whether their proposed
development location overlaps with ``sensitive wildlife habitat,'' or
is within a restricted surface occupancy (RSO) area. If it does, the
COGCC rules require that the Commission consult with CPW, the operator
and the surface owner to allow it to determine whether conditions of
approval are necessary to ``minimize adverse impacts'' from the
proposed oil and gas operations in the identified sensitive wildlife
habitat or RSO area (COGCC 2014). For purposes of this rule, ``minimize
adverse impacts'' means, ``wherever reasonably practicable, to (i)
avoid adverse impacts from oil and gas operations on wildlife
resources, (ii) minimize the extent and severity of those impacts that
cannot be avoided, (iii) mitigate the effects of unavoidable remaining
impacts, and (iv) take into consideration cost-effectiveness and
technical feasibility with regard to actions taken and decisions made
to minimize adverse impacts to wildlife resources, consistent with the
other provisions of the Act.'' (Id.) Consultation with CPW is not
required under certain circumstances, however, such as when the
Director of the COGCC issues a variance, a previously CPW-approved
wildlife mitigation plan exists, and others (COGCC 2014).
All oil and gas operations in sensitive wildlife habitat or RSO
areas authorized since implementation of the regulations in 2009 are
also required to comply with specified general operating requirements,
including (1) educating employees and contractors on conservation
practices, (2) consolidating new facilities to minimize disturbance,
(3) controlling road access and limiting traffic, where approved by the
surface owner and appropriate authorities, and (4) monitoring wells
remotely when possible (COGCC 2014). The COGCC Director may waive these
requirements, however (COGCC 2014). With respect to RSO areas,
operators are also required to avoid these areas in planning and
conducting new oil and gas operations ``to the maximum extent
technically and economically feasible,'' again subject to various
exceptions (COGCC 2014).
The 2009 COGCC rules identified certain areas as ``sensitive
wildlife habitat'' and RSO areas for Gunnison sage-grouse (COGCC 2009).
In September 2013, COGCC amended its rules to, among other things,
update and expand the definitions and maps of sensitive wildlife
habitat and RSO areas for Gunnison sage-grouse (COGCC 2013). The COGCC
rules as amended define sensitive wildlife habitat for the Gunnison
sage-grouse lek based on 4 mile buffers around lek sites and RSO areas
for the species as areas within 0.6 miles of a lek (COGCC 2014; COGCC
2013).
We find that while COGCC's rules provide for greater consideration
of Gunnison sage-grouse needs, the rules only apply to oil and gas
development, and they do not adequately address the threats to Gunnison
sage-grouse. Oil and gas operations that were approved before the
COGCC's 2009 adoption of the wildlife protection rules are not subject
to Rule 1202's wildlife consultation and conditions of approval
requirements, for example, even if operations have not yet begun (COGCC
2014). The limitations on new oil and gas development operations in RSO
areas also do not apply to applications that were approved before May
1, 2009 on federal land or April 1, 2009 on all other land (COGCC
2014). Unless operations change in a manner that requires additional
COGCC authorization, drilling operations that are already on the
landscape may continue to operate without further restriction into the
future. In addition, the COGCC regulations qualify implementation of
many of its conservation measures to ``wherever reasonably
practicable'' and like terms, which can limit the effectiveness of
these measures in avoiding or minimizing impacts to the species. We
also are not aware of any situations where RSOs have been effectively
applied or where conservation measures have been implemented for
potential oil and gas development impacts to Gunnison sage-grouse on
private lands underlain with privately owned minerals.
Colorado and Utah have laws that directly address the priorities
for use of State school section lands, which require that management of
these properties be based on maximizing financial returns. We have no
information on any conservation measures that will be implemented under
statutes or regulations for Gunnison sage-grouse on State school
section lands.
[[Page 69282]]
In 2007, the Colorado State Land Board (SLB) purchased the
Miramonte Meadows property (approximately 809 ha (2,300 ac) next to the
Dan Noble State Wildlife Area (SWA)). Roughly 526 ha (1,300 ac) of this
property is considered prime Gunnison sage-grouse habitat (Garner 2010,
pers. comm.). Discussions with the SLB have indicated a willingness to
implement habitat improvements (juniper removal) on the property. They
have also accepted an application to designate the tract as a
``Stewardship Trust'' parcel. The Stewardship Trust program is capped
at 119,383 to 121,406 ha (295,000 to 300,000 ac), and no more property
can be added until another tract is removed from the program. Because
of this cap, it is unknown if or when the designation of the tract as a
Stewardship Trust parcel may occur. The scattered nature of State
school sections (generally single sections of land) across the
landscape and the requirement to conduct activities to maximize
financial returns minimize the likelihood of implementation of measures
that will benefit Gunnison sage-grouse. Thus, no regulatory mechanisms
are present on State trust lands to minimize habitat decline and thus
help ensure conservation of the species. However, State school section
lands account for only 1 percent of occupied habitat in Colorado and 1
percent in Utah, so impacts from development and relevant laws or
regulation pertaining to State lands may be negligible in terms of
effects on Gunnison sage-grouse.
Some States require landowners to control noxious weeds, which are
a potential habitat threat to sage-grouse (as discussed in Factor A,
Invasive Plants). The types of plants considered to be noxious weeds
vary by State. Cheatgrass, which is a particular threat to sage-grouse,
is listed as a Class C species in Colorado (Colorado Department of
Agriculture 2010, p. 3). The Class C designation delegates to local
governments the choice of whether or not to implement activities for
the control of cheatgrass. Gunnison, Saguache, and Hinsdale Counties
target cheatgrass with herbicide applications (GWWC 2009, pp. 2-3). The
CPW annually sprays for weeds on SWAs (CDOW 2009b, p. 106). The State
of Utah, however, does not consider cheatgrass as noxious within the
State (Utah Department of Agriculture 2010a, p. 1) nor in San Juan
County, Utah (Utah Department of Agriculture 2010b, p. 1). The laws
dealing with other noxious and invasive weeds may provide some
protection for sage-grouse in local areas by requiring some control of
the invasive plants, although large-scale control of the most
problematic invasive plants is not occurring. Rehabilitation and
restoration techniques for sagebrush habitats are mostly unproven and
experimental (Pyke 2011, p. 543). Neither Colorado nor Utah's
regulatory mechanisms have been demonstrated to be effective in
addressing the overall impacts of invasive plants on the decline of
sagebrush habitat within the species' range.
Federal Laws and Regulations
Gunnison sage-grouse are not covered or managed under the
provisions of the Migratory Bird Treaty Act (16 U.S.C. 703-712) because
they are considered resident game species. Federal agencies are
responsible for managing 54 percent of the total Gunnison sage-grouse
habitat. The Federal agencies with the most sagebrush habitat are BLM,
an agency of the Department of the Interior, and USFS, an agency of the
Department of Agriculture. The NPS in the Department of the Interior
also has responsibility for lands that contain Gunnison sage-grouse
habitat.
BLM
About 42 percent of Gunnison sage-grouse occupied habitat is on
BLM-administered land (see Table 1). The Federal Land Policy and
Management Act of 1976 (FLPMA) (43 U.S.C. 1701 et seq.) is the primary
Federal law governing most land uses on BLM-administered lands. Section
102(a)(8) of FLPMA specifically recognizes wildlife and fish resources
as being among the uses for which these lands are to be managed.
Regulations pursuant to FLPMA (30 U.S.C. 181 et seq.) and other
statutory authorities that address wildlife habitat protection on BLM-
administered land include 43 CFR 3162.3-1 and 43 CFR 3162.5-1 (oil and
gas); 43 CFR 4120 et seq. (grazing); and 43 CFR 4180 et seq. (grazing).
Gunnison sage-grouse has been designated as a BLM Sensitive Species
since they were first identified and described as a species in 2000
(BLM 2009a, p. 7). The management guidance afforded sensitive species
under BLM Manual 6840--Special Status Species Management (BLM 2008,
entire) states that ``Bureau sensitive species will be managed
consistent with species and habitat management objectives in land use
and implementation plans to promote their conservation and to minimize
the likelihood and need for listing'' under the Act (BLM 2008, p. 05V).
BLM Manual 6840 further requires that Resource Management Plans (RMPs)
should address sensitive species, and that implementation ``should
consider all site-specific methods and procedures needed to bring
species and their habitats to the condition under which management
under the Bureau sensitive species policies would no longer be
necessary'' (BLM 2008, p. 2A1). As a designated sensitive species under
BLM Manual 6840, sage-grouse conservation must be addressed in the
development and implementation of RMPs on BLM lands.
RMPs are the basis for all actions and authorizations involving
BLM-administered lands and resources. They establish allowable resource
uses, resource condition goals and objectives to be attained, program
constraints and general management practices needed to attain the goals
and objectives, general implementation sequences, and intervals and
standards for monitoring and evaluating the plan to determine its
effectiveness and the need for amendment or revision (43 CFR 1601 et
seq.).
The RMPs also provide a framework and programmatic guidance for
activity plans, which are site-specific plans written to implement
decisions made in an RMP. Examples include Allotment Management Plans
that address livestock grazing, oil and gas field development, travel
management (motorized and mechanized road and trail use), and wildlife
habitat management. Activity plan decisions normally require additional
planning and National Environmental Policy Act (NEPA) analysis. If an
RMP contains specific direction regarding Gunnison sage-grouse habitat,
conservation, or management, the specific direction for the species is
an enforceable regulatory mechanism to ensure that the species and its
habitats are considered during permitting and other decision making for
activities that occur on BLM lands.
The BLM in Colorado manages Gunnison sage-grouse habitat under six
existing RMPs. These include the Gunnison Field Office (1993),
Uncompahgre Field Office (1989), Gunnison Gorge National Conservation
Area (NCA) (2004), Tres Rios Field Office (1985), Grand Junction Field
Office (1987), and San Luis Valley Field Office (1991) RMPs. A new RMP
for the BLM Dominguez-Escalante NCA, designated in 2009 and
encompassing Gunnison sage-grouse habitat in the vicinity of the
Pi[ntilde]on Mesa population, is also under development.
In Utah, Gunnison sage-grouse habitat falls under the Monticello
Field Office (2008) and Moab Field Office (2008) RMPs. All six of the
existing Colorado RMPs contain broad objectives for Gunnison sage-
grouse conservation, but lack specific land use allocation
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decisions, stipulations, and enforceable measures to achieve those
objectives. Three of these RMPs were under revision as of the drafting
of this rule, including the Tres Rios, Grand Junction, and Uncompahgre
Field Offices, covering all or portions of the San Miguel, Pi[ntilde]on
Mesa, Crawford, Cerro Summit-Cimarron-Sims Mesa, and Dove Creek
populations.
All ongoing RMP revisions include in their range of alternatives or
preferred alternative various stipulations and measures, such as
spatial buffers, seasonal limitations, and other site-specific
restrictions and best management practices, for land use activities in
important Gunnison sage-grouse habitat (leks, nesting habitat, brood-
rearing habitat, winter habitat). Many of these recommendations are
derived or adapted from the RCP (GSRSC 2005, entire) or local Gunnison
sage-grouse working group plans (see Multi-County and Rangewide Efforts
in Factor A above) and should provide conservation benefits to the
species and its habitat, if adopted into Final RMP Plan Revisions and
Records of Decision (BLM 2009a, p.6).
In May of 2014, BLM Headquarters issued guidance and direction to
BLM Colorado and Utah to undertake a landscape-level, targeted RMP
Amendment for the conservation of Gunnison sage-grouse on BLM-
administered public lands in Colorado and Utah (BLM 2014a). This
process is expected to be completed within 18-24 months, and will
evaluate the adequacy of all current RMPs, including those which may be
revised during the current plan amendment review process. It is unknown
what conservation measures will be included in the planned RMP
Amendments or in the three BLM Colorado RMPs that are currently under
revision rangewide.
All existing Colorado BLM RMPs date from 1985 to 1993 and, as
described above, contain broad objectives for Gunnison sage-grouse
conservation, but generally lack specific land use allocation
decisions, stipulations, and enforceable measures to ensure that those
objectives are achieved. This may be attributed, in part, to the
broader view and approach in land use planning and resource decisions
typical of older RMPs.
More recent (i.e., 2000 and later) RMPs or revisions typically
contain more detailed and resource-specific decisions and protections
than their predecessors. The Gunnison Gorge NCA RMP (BLM 2004) contains
management decisions adequate to conserve Gunnison sage-grouse and its
habitat in the Crawford population. This RMP designates an ACEC in
habitat occupied by Gunnison sage-grouse where management and
protection of the Gunnison sage-grouse and its habitat will be
emphasized. Within this area, the plan contains specific protections to
maintain or increase Gunnison sage-grouse numbers and its distribution,
improve the quality of sage-grouse habitat, and to prevent, minimize
and mitigate fragmentation and loss of habitat. The RMP adopts and
incorporates the Gunnison sage-grouse conservation plan, Crawford Area,
Colorado (Crawford Area Gunnison Sage-Grouse Working Group 2011), as
part of the direction and management objectives of the ACEC.
Current BLM RMPs in Utah and Colorado do provide limited regulatory
protection for Gunnison sage-grouse as they are implemented through
project-level planning. These protections include conservation measures
to be implemented during travel management (the management of the
motorized and non-motorized use of public lands), energy development,
and grazing permit renewals.
The 2008 Final RMP for the BLM Monticello Field Office in Utah
incorporates the recommendations of the 2005 RCP, which provides a
level of benefit for Gunnison sage-grouse. For example, this RMP
precludes oil and gas development, roads, power lines, fences, and
other aboveground structures within 0.6 mile of a Gunnison sage-grouse
lek. It also prohibits grazing in allotments containing Gunnison sage-
grouse during the breeding season, It does not, however, specifically
limit oil and gas development and the construction of other
infrastructure in Gunnison sage-grouse habitat beyond 0.6 mile, which
includes nesting, brood rearing, and wintering habitat.
In general, other than the Gunnison Gorge NCA RMP, the remaining
RMPs provide only partial protection for Gunnison sage-grouse in terms
of land use allocation decisions specific to the species and its
habitat and, therefore, are considered inadequate to protect the
species
In addition to land use planning through its RMPs, BLM uses
Instruction Memoranda (IM) to provide instruction to district and field
offices regarding specific resource issues. Instruction Memoranda
provide policy guidance or directives, but do not contain binding legal
decisions such as those promulgated under an RMP. IMs are temporary
directives, generally of short duration (1 to 2 years), intended to
address urgent resource concerns by providing interim direction to
staff until a threat passes or until the resource issue can be
addressed through revisions or updates to manuals or RMPs.
BLM has issued a number of IMs addressing Gunnison sage-grouse. On
July 12, 2005 BLM Colorado issued IM Number CO-2005-038, stating BLM's
intent and commitment to assist with and participate in the
implementation of the 2005 RCP. This guidance has been used for BLM-
administered lands in the State of Colorado to provide conservation
benefit for Gunnison sage-grouse (BLM 2009a, p. 6). On August 17, 2010,
BLM Colorado issued IM number CO-2010-028 on Gunnison sage-grouse and
greater sage-grouse habitat management policy, which provides direction
regarding implementation of National BLM sage-grouse guidance, ensures
continued coordination with CPW and other agency partners regarding
sage-grouse conservation planning, and calls for fluid mineral leasing
deferrals in core Greater sage-grouse habitats until Field Office plan
revisions have been completed (BLM 2010b, entire).
On July 15, 2013, BLM Colorado issued IM Number CO-2013-033 to
provide policy guidance to Colorado Field Offices on Gunnison sage-
grouse habitat management, land uses, and resource management planning
(BLM 2013d, p. 1). This IM updated and superseded the 2010 IM, Number
CO-2010-028. The 2013 IM was developed in coordination with the Service
and provided direction regarding management and ongoing land use
planning in Gunnison sage-grouse occupied habitat, including the
application of specific conservation measures for the species (BLM
2013d, p. 2).
On May 30, 2014, BLM HQ issued a new IM, 2014-100, which applies to
all Gunnison sage-grouse proposed occupied critical habitat in both
Colorado and Utah (BLM 2014b entire). In order to protect important
habitat across the range of the species, BLM will continue to apply
conservation measures and focus any type of development in non-habitat
areas. All disturbances will be focused outside of a 4-mile buffer
around leks, except where there are valid existing rights or where
benefits to Gunnison sage-grouse may be greater than under other
alternatives (BLM 2014b, p.1). The Policy identifies conservation
measures for activities including Land Use Planning, Proper Livestock
Grazing, Wildland Fire and Fuels Management, Processing Fluid Mineral
Leases and Solid Mineral Leases (BOM 2014b pp. 2-5). This IM is
expected to remain in effect until the RMP Amendment
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process is complete in 2016. While this IM is of short duration, we
anticipate that its implementation will reduce threats to the Gunnison
sage-grouse on BLM lands from the covered activities.
Fluid Minerals
The BLM has regulatory authority for oil and gas leasing on Federal
lands and on private lands with a severed Federal mineral estate, as
provided at 43 CFR 3100 et seq., and they are authorized to require
stipulations as a condition of issuing a lease. The BLM's Land Use
Planning Handbook describes program-specific guidance for fluid
minerals (which include oil and gas) and the handbook specifies that
RMP decisions will identify restrictions on areas subject to leasing,
including closures, as well as lease stipulations (BLM 2005e, Appendix
C, pp. 23-24). The handbook also specifies that all stipulations must
have waiver, exception, or modification criteria documented in the
plan, and notes that the least restrictive constraint to meet the
resource protection objective should be used (BLM 2005e, Appendix C,
pp. 23-24).
To our knowledge, BLM Field Offices are deferring the sale of new
drilling leases, which was first implemented in the 2010 IM, in
habitats they have identified as ``priority'' or ``core'' habitats for
Gunnison sage-grouse until RMP revisions are complete and/or adequate
protective lease stipulations are in place. However, there is currently
no regulatory mechanism in effect which assures that future lease sales
in occupied habitat on BLM administered lands will not occur or that
operations on federal leases are conducted in a manner consistent with
protection of the Gunnison sage-grouse.
In addition, oil and gas leases already exist in 17 percent of the
Pi[ntilde]on Mesa population area, and 49 percent of the San Miguel
Basin population. For existing oil and gas leases on BLM land in
occupied Gunnison sage-grouse habitat, oil and gas companies may
conduct drilling operations subject to BLM-imposed permit conditions.
Specifically, the BLM has regulatory authority to condition
``Application for Permit to Drill'' authorizations that are conducted
under a lease that does not contain specific Gunnison sage-grouse
conservation stipulations, consistent with lease rights, but
utilization of these conditions is discretionary and we are uncertain
at this time how widely such authority has or will be applied to avoid
or minimize impacts to Gunnison sage-grouse.
We also note that onshore federal oil and gas leases include a
provision (also known as a standard lease term) that allows movement of
the drilling area or facilities by 200m (650ft) to avoid sensitive
resources (43 CFR 3101.1(c)). However, in most cases this small amount
of movement would have little to no conservation benefit to Gunnison
sage-grouse because sage-grouse respond to nonrenewable energy
development at much further distances (Holloran et al. 2007, p. 12;
Walker et al. 2007, p. 10). Pursuant to its permitting authority as
described above, our experience is that many of the BLM field offices
work with the operators to move a proposed drilling site farther from
sensitive resources and justify such a move through a site-specific
NEPA process.
Given the already small and fragmented nature of the populations
where future oil and gas leases are likely to occur, additional
development within occupied habitat would negatively impact those
populations by contributing to further habitat decline. Since we have
no information on what minimization and mitigation measures might be
applied to future leases at this time, we cannot assess the
conservation benefit of potential BLM regulations to those populations.
Salable and Locatable Minerals
As discussed under Factor A (Locatable and Salable Mineral
Development), currently active mines and mining claims are limited in
geographic scope and mining is expected to have limited impacts on
Gunnison sage-grouse populations. As a result, we found current
locatable and salable mineral development to be a threat of low
magnitude to Gunnison sage-grouse. We have no information indicating
that any regulatory mechanisms currently exist to reduce impacts of
mines.
Grazing
As stated previously, Gunnison sage-grouse are a BLM Sensitive
Species and therefore receive Special Status Species management
considerations. The BLM regulatory authority for grazing management is
provided at 43 CFR part 4100 (Regulations on Grazing Administration
Exclusive of Alaska). Livestock grazing permits and leases contain
terms and conditions determined by BLM to be appropriate to achieve
management and resource condition objectives on the public lands and
other lands administered by BLM, and to ensure that habitats are, or
are making significant progress toward being, restored or maintained
for BLM special status species (43 CFR 4180.1(d)). BLM's State or
regional standards for grazing administration must address habitat for
endangered, threatened, proposed, candidate, or special status species,
and habitat quality for native plant and animal populations and
communities (43 CFR 4180.2(d)(4) and (5)). BLM's guidelines for
ensuring that grazing standards are met similarly must address
restoring, maintaining, or enhancing habitats of BLM special status
species to promote their conservation, as well as maintaining or
promoting the physical and biological conditions to sustain native
populations and communities (43 CFR 4180.2(e)(9) and (10)); BLM 2009b,
p. 8). The BLM is required to take appropriate action no later than the
start of the next grazing year upon determining that existing grazing
practices or levels of grazing use are significant factors in failing
to achieve the standards and conform with the guidelines (43 CFR
4180.2(c)).
The BLM is required to consult with their Resource Advisory
Councils (RACs) to expand the rangeland health standards required under
43 CFR part 4180 so that there are public land health standards
relevant to all ecosystems, not just rangelands, and that these
standards apply to all BLM programs and actions across public lands,
not just livestock grazing (BLM Land Health Manual 4180 (BLM 2009b, p.
8)). Both southwest Colorado and southeast Utah have RACs established
by the BLM.
A detailed analysis of grazing on BLM-administered lands and its
impacts on the Gunnison sage-grouse is included above in Factor A. As
of 2012, all active BLM grazing permits in occupied Gunnison sage-
grouse habitat managed by the BLM Gunnison Field Office have vegetation
structure guidelines specific to Gunnison sage-grouse incorporated into
Allotment Management Plans or Records of Decision for permit renewals
as habitat objectives (BLM 2012a, pp. 3-4). These Gunnison sage-grouse
habitat objectives are designed to provide good habitat for the
species. Similar objectives are also incorporated into Allotment
Management Plans in portions of some of the smaller population areas
(see section, Public Lands Grazing in other Population Areas under
Factor A). However, as noted earlier (see Domestic Grazing and Wild
Ungulate Herbivory under Factor A), available information suggests that
LHA objectives important to Gunnison sage-grouse are not being met
across parts of the species' range. Reduced habitat quality in those
areas, as reflected in unmet LHA objectives, may be negatively
impacting Gunnison sage-grouse. However, the relationship between LHA
determinations and the effects of domestic livestock grazing on
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Gunnison sage-grouse is difficult to quantify.
Specific Gunnison sage-grouse habitat objectives from the 2005 RCP
are incorporated into some Federal grazing permits and are an effective
means of ensuring that the needs of Gunnison sage-grouse are met on
grazed lands. Certain grazing permits also contain standard terms and
conditions, such as forage utilization standards, that may indirectly
help achieve habitat objectives for Gunnison sage-grouse. However,
terms and conditions applied within BLM's existing livestock grazing
permits and leases are currently inadequate in parts of the range of
Gunnison sage-grouse. As discussed under Factor A (Summary of Domestic
Grazing and Wild Ungulate Herbivory), the best available information
suggests that Land Health Assessment objectives important to Gunnison
sage-grouse are not being met across localized parts of the species'
range and that livestock grazing is likely contributing to those
conditions in some instances. Reduced habitat quality in those areas,
as reflected in LHA data, is likely negatively impacting Gunnison sage-
grouse in some of the populations. While it is anticipated that future
terms and conditions in BLM grazing permits will minimize further
grazing impacts to habitat on BLM-administered lands, it is currently
unknown what terms and conditions might be incorporated into grazing
permits and how such terms and conditions may improve degraded habitats
for Gunnison sage-grouse.
USFS
The USFS manages 10 percent of the occupied Gunnison sage-grouse
habitat (Table 1). Management of National Forest System lands is guided
principally by the National Forest Management Act (NFMA) (16 U.S.C.
1600-1614, August 17, 1974, as amended). The NFMA specifies that all
National Forests must have a Land and Resource Management Plan (LRMP)
(16 U.S.C. 1600) to guide and set standards for all natural resource
management activities on each National Forest or National Grassland.
The NFMA requires USFS to incorporate standards and guidelines into
LRMPs (16 U.S.C. 1600), which include provisions to manage plant and
animal communities for diversity, based on the suitability and
capability of the specific land area in order to meet overall multiple-
use objectives.
The Gunnison sage-grouse is a USFS sensitive species in both Region
2 (Colorado) and Region 4 (Utah). USFS policy provides direction to
USFS Forests to analyze potential impacts of programs and activities to
endangered, threatened, proposed, or sensitive species in a biological
evaluation. The National Forests within the range of sage-grouse
provide important seasonal habitats for the species, particularly the
Grand Mesa, Uncompahgre, and Gunnison (collectively known as GMUG)
National Forests. The 1991 Amended Land and Resource Management Plan
for the GMUG National Forests has not incorporated Gunnison sage-grouse
conservation measures or habitat objectives. Similarly, the 1996 the
Forest Plan for the Rio Grande National Forest does not contain
Gunnison sage-grouse specific conservation measures. The newer 2013
Forest Plan for the San Juan National Forest does contain measures to
protect Gunnison sage-grouse, although there is very little Gunnison
sage-grouse habitat on this national forest. The Regional Forester
signed the 2005 RCP, agreeing to follow and implement the
recommendations in the plan. Nonetheless, only three of the 34 grazing
allotments in occupied grouse habitat on National Forest lands have
incorporated Gunnison sage-grouse habitat objectives from the RCP,
indicating that USFS regulations and the USFS agreement to implement
the RCP are currently inadequate to protect the species.
The only Gunnison sage-grouse population within USFS lands that is
in an area of high or even medium potential for oil and gas reserves is
the San Miguel Basin, and USFS lands only make up 1.4 percent of that
population (GSRSC 2005, D-8). Although the 2014 BLM IM does not
specifically apply to USFS lands, USFS considers the IM in evaluating
leasing decisions. The BLM, which regulates oil and gas leases on USFS
lands, has the authority to defer leases and would make a leasing
decision consistent with their 2014 IM in coordination with USFS
(McDonald 2014, pers. com).
While USFS consideration of Gunnison sage-grouse as a sensitive
species and commitment to follow the recommendations contained in the
2005 RCP (GSRSC 2005, entire) can provide some conservation benefits to
the species, both of these actions are primarily voluntary in nature
and thus are not treated as regulatory mechanisms in our evaluation
process. Considering the above information, the USFS has implemented
some regulatory mechanisms and policies to provide for the long-term
conservation of Gunnison sage-grouse and is a signatory to the CCA for
the Gunnison Basin (see Factors A and E). However, we find that USFS
regulations are not fully addressing the conservation of Gunnison sage-
grouse because the GMUG and Rio Grande National Forests, which cover
the vast majority of Gunnison sage-grouse habitats on national forest
lands, are governed by older Forest Plans that do not contain detailed
conservation standards for this species.
NPS
The NPS manages 2 percent of occupied Gunnison sage-grouse habitat
(Table 1), which means that there is little opportunity for the agency
to affect range-wide conservation of the species. The NPS Organic Act
(16 U.S. C. Sec. 1) states that NPS will administer areas under their
jurisdiction ``by such means and measures as conform to the fundamental
purpose of said parks, monuments, and reservations, which purpose is to
conserve the scenery and the natural and historical objects and the
wildlife therein and to provide for the enjoyment of the same in such
manner and by such means as will leave them unimpaired for the
enjoyment of future generations.'' Lands in the Black Canyon of the
Gunnison National Park and the Curecanti National Recreation Area
include portions of occupied habitat in the Crawford and Gunnison Basin
populations and are managed under NPS's General Management Plan for
these Park units (NPS 1997, entire). Under this plan, resource
objectives related to Gunnison sage-grouse include protection of the
species and its habitat, protection of threatened and endangered
species, and minimization of the causes and impacts of habitat
fragmentation (NPS 1997, pp. 18-19). In addition, the NPS has nearly
completed an area Resource Stewardship Strategy, a plan that identifies
more specific conservation measures and actions, including an emphasis
on Gunnison sage-grouse conservation, for implementation of the General
Management Plan (Stahlnecker 2014, pers. comm.). In the meantime, NPS's
ability to actively manage for Gunnison sage-grouse is not limited by
the scope of their management plans, as discussed below.
The NPS completed a Fire Management Plan in 2006 that covers both
of the areas mentioned above (NPS 2006, entire). Both prescribed fire
and fire use (allowing wildfires to burn) are identified as a suitable
use in Gunnison sage-grouse habitat. However, Gunnison sage-grouse
habitat is identified as a Category C area, meaning that, while fire is
a desirable component of the ecosystem, ecological constraints must be
observed. For Gunnison sage-grouse, constraints in the plan include
limitation of acreage burned per year
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and limitation of percent of project polygons burned. Moreover, the NPS
is currently following the fire-related conservation measures in the
local conservation plans as described in Multi-County and Rangewide
Conservation Efforts above under Factor A, and the 2005 RCP fire
recommendations (Stahlnecker 2010, pers. comm.). In most cases,
implementation of NPS fire management policies should result in minimal
adverse effects since emphasis is placed on activities that will
minimize impacts to Gunnison sage-grouse habitat. Overall,
implementation of NPS plans should reduce impacts to Gunnison sage-
grouse because they include conservation measures to protect Gunnison
sage-grouse habitat.
Recreational activities are generally managed more intensively on
NPS land than on other Federal lands. Nevertheless, recreational
activities within occupied habitat on NPS land may have adverse effects
on Gunnison sage-grouse individuals (see Factor E discussion). However,
given the limited amount of occupied habitat on NPS land (2 percent of
the Gunnison Basin population area), recreation on those lands is
likely having negligible impacts on Gunnison sage-grouse at the
population or species level.
Grazing management activities on NPS lands are governed by BLM
regulations, and their implementation and the results of these
regulations are likely similar to those discussed for the BLM, because
they occur under the same management criteria and guidance. In 2013,
all of the active allotments in the Crawford population, including NPS
allotments, had incorporated Gunnison sage-grouse habitat objectives
and completed LHAs (see Grazing section in Factor A). Grazing
management plans on NPS lands appear to be provide conservation
measures for the species. Overall, NPS regulations reduce threats to
Gunnison sage-grouse on the 2 percent of occupied habitat in the
Gunnison Basin population under NPS jurisdiction. However, they do not
significantly reduce threats on a rangewide basis.
Environmental Protection Agency
On December 15, 2009, the EPA published in the Federal Register (74
FR 66496) a rule titled, ``Endangerment and Cause or Contribute
Findings for Greenhouse Gases under Section 202(a) of the Clean Air
Act.'' In this rule, the EPA Administrator found that the current and
projected concentrations of the six long-lived and directly emitted
greenhouse gases--carbon dioxide, methane, nitrous oxide,
hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride--in the
atmosphere threaten the public health and welfare of current and future
generations; and that the combined emissions of these greenhouse gases
from new motor vehicles and new motor vehicle engines contribute to the
greenhouse gas pollution that threatens public health and welfare. In
effect, the EPA has concluded that the greenhouse gases linked to
climate change are pollutants, whose emissions can now be subject to
the Clean Air Act (42 U.S. C. 7401 et se.; see 74 FR 66496, December
15, 2009). On October 15, 2012, EPA and the National Highway
Transportation Safety Administration (NHTSA) issued a joint Final
Rulemaking to extend the National Program of harmonized greenhouse gas
and fuel economy standards to model year 2017 through 2025 passenger
vehicles (77 FR 62624). On June 17, 2013, EPA and NHTSA implemented
standards for medium- and heavy-duty vehicles (model years 2014 through
2018) (78 FR 36370). These regulations are relatively new, and at
present, we have no basis to conclude that implementation of the Clean
Air Act in the near future (40 years, based on global climate
projections) will substantially reduce the current rate of global
climate change through regulation of greenhouse gas emissions. Thus, we
conclude that while the Clean Air Act may reduce greenhouse gas
emissions, it does not address the primary threats to the Gunnison
sage-grouse, such as drought, nonnatives, fire frequency, and decrease
of sagebrush.
Other Regulatory Mechanisms: Conservation Easements
Conservation easements are voluntary legal agreements between a
landowner and a land trust, nongovernmental organization, or government
agency that permanently limit or restrict land uses for identified
conservation values and purposes and are binding regulatory mechanisms
once established. With very few exceptions, conservation easements
require that individual parcels be owned and conveyed as single units
in perpetuity, thereby ensuring they are not subdivided for development
in the future. Conservation easements also restrict land uses by
defining specific areas for residential or agricultural development,
including roads and driveways, and may include other parameters for
land management practices to achieve conservation values (Lohr and Gray
2013, p. 2). Therefore, we generally consider conservation easements to
be an effective regulatory tool to prevent long-term or permanent
habitat loss. Conservation easements across Gunnison sage-grouse range
are held by nongovernmental organizations and land trusts (The Nature
Conservancy, Colorado Cattlemen's Agricultural Land Trust, and others),
state agencies (CPW, UDWR), and Federal agencies (Natural Resources
Conservation Service (NRCS), NPS, and BLM). Some conservation easements
include conservation measures specific to Gunnison sage-grouse, while
many are directed at other species, such as big game (GSRSC 2005, pp.
59-103).
Following is a summary of the estimated amount of lands under
conservation easement for occupied and unoccupied Gunnison sage-grouse
habitat in Colorado and Utah, based on Lohr and Gray (2013, entire)
(Table 12). This report also included lands not under conservation
easement, but which are owned by entities that manage the property for
Gunnison sage-grouse and other conservation values (e.g., The Nature
Conservancy properties), or which carry covenants that restrict
subdivision and development in perpetuity (e.g., Eagle Ridge Ranch in
the Gunnison Basin). Rangewide, approximately 35,195 ha (86,968 ac), or
22.6 percent, of private lands in occupied Gunnison sage-grouse habitat
were under conservation easement as of 2013 (Lohr and Gray 2013,
entire). Another 51,040 ac, or 11 percent, of private lands in mapped
unoccupied habitat are also under conservation easement (Lohr and Gray
2013, entire). Combined, conservation easements include approximately
138,008 ac, or 16 percent, of all occupied and unoccupied habitat on
private land (840,346 ac) across the species' range.
Of all the Gunnison sage-grouse populations, the Gunnison Basin
contains the most acres under conservation easement (102,986 ac total
in occupied and unoccupied habitat). In proportion to total occupied
habitat, conservation easements in the Pi[ntilde]on Mesa and Crawford
population areas are significant (74 and 41 percent, respectively).
Approximately 30 percent of private land in unoccupied habitat is also
protected under conservation easement in the Gunnison Basin and
Crawford population areas (Table 12).
[[Page 69287]]
Table 12--Conservation Easements in Gunnison Sage-Grouse Occupied \a\ and unoccupied \a\ Habitats
[Lohr and Gray 2013, entire; Gunnison County 2013b, p. 21]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Private land in occupied Private land in unoccupied
Private land habitat under CE Private land habitat under CE
Population in occupied -------------------------------- in unoccupied -------------------------------
habitat (ac) Acres % of total habitat (ac) Acres % of total
--------------------------------------------------------------------------------------------------------------------------------------------------------
Monticello-Dove Creek................................... 100,702 6,117 5 200,318 0 0
Pi[ntilde]on Mesa....................................... 27,283 20,076 74 64,275 20,246 31
San Miguel Basin........................................ 49,492 6,938 14 45,843 1,486 3
Cerro Summit-Cimarron-Sims Mesa......................... 28,218 3,995 14 20,117 3,774 19
Crawford................................................ 8,481 3,470 41 44,552 8,665 20
Gunnison Basin.......................................... 178,531 46,372 26 56,614 16,348 29
Poncha Pass............................................. 4,792 0 0 11,128 521 5
Rangewide Totals.................................... 397,499 86,968 22 442,847 51,040 12
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Occupied and unoccupied habitat acres and conservation easements provided in Lohr and Gray (2013) were based on the Service's proposed critical
habitat designation for Gunnison sage-grouse (78 FR 2540, January 11, 2013).
In the context of potential threats to Gunnison sage-grouse,
conservation easements and the protections they afford are most
relevant to the threat of residential and human development. Therefore,
in the Residential Development section of this rule (Factor A), we
further analyzed existing conservation easements by Gunnison sage-
grouse population and across the species' range. Therein, Table 6
summarizes conservation easement acres in occupied habitat for each
Gunnison sage-grouse population, and also provides estimates for those
portions of occupied habitat not under conservation easement, for the
purposes of evaluating the threat of residential development.
Total conservation easements recorded to date cover about 18.3
percent of private lands in rangewide occupied habitat for Gunnison
sage-grouse. The Service has analyzed the conservation and regulatory
benefit of existing conservation easements throughout the range of the
species. However, conservation easements are offered and held by
numerous entities and happen opportunistically with willing sellers
across the range of the species.
Summary of Factor D
Gunnison sage-grouse conservation has been addressed in some local,
State, and Federal, laws, regulations, and land management plans. We
commend Gunnison, San Miguel, Ouray, and Montrose Counties for enacting
special regulations for Gunnison sage-grouse for land uses within their
jurisdictions. Existing local laws and regulations will help to reduce
some of the negative effects of human development and infrastructure on
Gunnison sage-grouse. Continuation and enhancement of these efforts
across the species' range will be necessary for conservation of the
species. Past residential and exurban development throughout the
species range is a primary cause of habitat decline. Future human
development will further contribute to habitat loss (see Factor A,
Residential Development, Roads, and Powerlines). As described above,
existing local laws and regulations do not fully address this threat to
the species. Local regulatory mechanisms also do not fully address
other substantial threats to the species, including small population
size (Factor E), invasive plants (Factor A), disease (Factor B), and
climate change (Factor A).
Implementation of Federal agency regulations specifically for
Gunnison sage-grouse conservation provides obvious benefits to the
species, considering that approximately 54 percent of rangewide
occupied habitat occurs on Federal lands (Table 1). Protections
afforded to Gunnison sage-grouse vary by agency and field office or
unit, but many of these protections are discretionary or undertaken on
a voluntary basis rather than required by a regulatory mechanism. BLM's
land use management plans are regulatory mechanisms, but for the most
part do not currently include requirements directed at sage-grouse
conservation. This will likely change in the future, as a result of the
ongoing revision process for some RMPs in the species' range and the
planned rangewide RMP Amendment to address sage-grouse threats.
Nonetheless, we do not know at this time what conservation measures
will be included in these future RMPs or the degree to which they may
address threats to the species. As a result, we do not consider or rely
on these future planning efforts in this rule. BLM's 2014 IM for
Gunnison sage-grouse in Colorado provides a more consistent foundation
for the management and conservation of the species on BLM land in
Colorado, but it is a temporary measure and is not a binding regulatory
mechanism. Based on this analysis, and our more detailed evaluation of
BLM and other possible Federal regulatory mechanisms, we find that
existing Federal laws and regulations are not fully addressing the full
scope of threats to the species (Factors A through C, and E).
The CPW, UDWR, and other entities have acquired and continue to
pursue conservation easements in Colorado and Utah, respectively, to
conserve Gunnison sage-grouse habitat and meet the species' needs. We
determined that perpetual conservation easements offer protection from
habitat loss, but that conservation values and objectives for those
properties vary according to the terms of the easement. Existing
conservation easements provide a level of protection from future
development on these lands, but are limited in geographic scope such
that they do not adequately address the threat of habitat loss across
the species' range. State wildlife regulations provide protection for
individual Gunnison sage-grouse from direct mortality due to hunting
but do not address habitat loss and other threats such as drought,
climate change, or disease. While the COGCC regulations discussed above
provide some protection and mitigation (as defined by COGCC, not the
Service) for loss of Gunnison sage-grouse habitat, they do not prevent
ongoing habitat loss and fragmentation (Factor A).
We evaluated the best available information related to existing
regulatory mechanisms that address threats (Factors A through C, and E)
to Gunnison sage-grouse and its habitats. Based on our analysis, we
find that some existing regulatory mechanisms are in place to conserve
Gunnison sage-grouse, but individually or collectively they do not
fully address the substantial
[[Page 69288]]
threats faced by Gunnison sage-grouse across their range. Further,
while these existing regulatory mechanisms may help reduce current
threats to the species, they are insufficient to fully reduce or
eliminate the increase in threats that may act on the species in the
future.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
Other factors potentially affecting the Gunnison sage-grouse's
continued existence include small population size and structure;
drought, recreational activities, pesticides and herbicides, and
contaminants.
Small Population Size and Structure
Negative effects on population viability, such as reduced
reproductive success or loss of genetic variation and diversity, become
more evident as populations decline or become more isolated. In this
section, we evaluate the issue of small and declining population size
and structure in Gunnison sage-grouse, and associated genetic risks and
other effects. We also evaluate existing population viability analyses
for the species. Finally, we synthesize this information to assess
resiliency, redundancy, and representation of the individual Gunnison
sage-grouse populations and the species as a whole.
Relevant Species Information
In general, while various natural factors would not limit sage-
grouse populations across large geographic scales under historical
conditions or in larger populations, they may contribute to local
population declines or extirpations when populations are small,
isolated, or when weather patterns, habitats, or mortality rates are
altered. When coupled with mortality stressors related to human
activity and significant fluctuations in annual population size, long-
term persistence of small populations (in general) is unlikely (Traill
et al. 2010, entire). Sage-grouse have low reproductive rates and high
annual survival rates (Schroeder et al. 1999, pp. 11, 14; Connelly et
al. 2000a, pp. 969-970), resulting in a long recovery period from
disturbances due to slower potential or intrinsic population growth
rates than is typical of other game birds. Also, as a consequence of
their site fidelity to seasonal habitats (Lyon and Anderson 2003, p.
489), measurable population effects may lag behind negative changes in
habitat (Harju et al. 2010, entire; Wiens and Rotenberry 1985, p. 666).
As described in the Current Distribution and Population Estimates
and Trends subsection in the Background section above, the Gunnison
Basin is the largest population of Gunnison sage-grouse (3978
individuals in 2014) and, while showing variation over the period of
record, has been relatively stable since 1996, based on lek count data
(Figure 2). However, as discussed later in this section, demographic
data indicate this population may not be quite as stable as suggested
by lek count data (Davis 2012, p. 38). The Gunnison Basin population
declined during the period 2005-2010, as shown by rates of growth
estimated from demographic parameter estimates measured during that
time period (Davis 2012, entire), and from lek count indices (CPW
2014e, entire). In addition to this, an integrated population model
that used this short term demographic data in conjunction with the
longer time series of lek count data estimated a rate of growth
slightly less than 1.0 (lambda = 0.984) with confidence intervals that
overlapped 1.0 (0.879-1.179) for the period 1996-2012 (Davis et al. in
press). This 1996-2012 estimate was not statistically significantly
different from a lambda of 1.0, suggesting the population is currently
largely stable. The Gunnison Basin population comprises about 84
percent of the rangewide population of Gunnison sage-grouse and
includes 63 percent of rangewide occupied habitat.
In contrast, the remaining six populations, also referred to in
this final rule as satellite populations, were generally in decline
from 1996 until 2010; however, increases in several populations have
been observed recently (Figure 3) and could be a product of numerous
factors including but not limited to population cycles, translocation
efforts, and increased access to leks. The San Miguel and Pi[ntilde]on
Mesa populations are currently the largest of the satellite
populations, with 206 and 182 birds, respectively, in 2014. The
Monticello-Dove Creek and Crawford populations currently have less than
160 birds. Population estimates in 2014 for the two smallest
populations, Cerro Summit-Cimarron-Sims Mesa and Poncha Pass, were 74
and 16, respectively (CPW 2014, p.6). The 16 radio-telemetered birds
known at Poncha Pass in summer 2014 are the remainder of 27 birds
translocated from Gunnison Basin in fall of 2013 and spring of 2014.
Based on lek count-based population estimates, some satellite
populations have increased slightly over the last several years, or
intermittently over time. However, the last 19 years (1996 to 2014) of
lek count data as a whole indicate that the satellite populations are
in decline, with the possible exception of the Cerro Summit-Cimarron-
Sims Mesa population which appears to be relatively stable to
increasing, and Pi[ntilde]on Mesa, which is at its highest over the 19
year period (Figure 3). However, some of the recent increases in
population sizes may be attributable to translocation and survey
efforts, rather than an actual increase in the population, which may be
the case with Pi[ntilde]on Mesa. For example, the 2014 estimated
population for Pi[ntilde]on Mesa was 182 birds (CPW 2014, p. 6), much
greater than the 2012 estimate of 54 birds. This increase could be, in
part, a product of the 93 birds translocated to Pi[ntilde]on Mesa
population between the spring of 2010 and spring of 2013 (CPW 2014c,
entire) and the discovery of two new leks in 2012 (CPW 2012a, pp. 2-3).
For all six satellite populations, population estimates from 1996 to
2014 are below population targets (based on a 10-year average), as set
forth by the RCP (CPW 2013, p. 11; GSRSC 2005, pp. 255-302) (see
Current Distribution and Population Estimates and Trends in the
Background section for more details). The RCP identified population
targets as attainable population sizes sufficient to conserve Gunnison
sage-grouse in those population areas (GSRSC 2005, p. 255). This
constitutes the current and best available information on population
targets for Gunnison sage-grouse.
Combined, the satellite populations comprise about 16 percent of
the rangewide population of Gunnison sage-grouse and include
approximately 37 percent of rangewide occupied habitat. Small
population size and population structure occur in all of the six
satellite populations, or across approximately 37 percent of occupied
range for the species. The small sizes of the satellite populations of
Gunnison sage-grouse make them particularly sensitive to stochastic and
demographic fluctuations, and this vulnerability is exacerbated by
other threats such as drought (GSRSC 2005, p. G-22). Small population
size, declining population trends, and apparent isolation indicate
long-term population persistence and evolutionary potential are
compromised in the satellite populations (see Genetic Risks).
Genetic Risks
Small populations face three primary genetic risks: Inbreeding
depression; loss of genetic variation; and accumulation of new
mutations. In general, these negative genetic consequences influence a
species' fitness, or ability to reproduce and survive in the face of
environmental pressures. Inbreeding can have individual and population
level
[[Page 69289]]
consequences by either increasing the phenotypic expression of
recessive, deleterious alleles (the expression of harmful genes through
the physical appearance) or by reducing the overall fitness of
individuals in the population (GSRSC 2005, p. 109 and references
therein).
Gunnison sage-grouse have low levels of genetic diversity,
particularly in comparison to greater sage-grouse (Oyler-McCance et al.
2005, p. 635). There is no consensus regarding how large a population
must be in order to prevent inbreeding depression. However, the San
Miguel Basin satellite population has an effective population size (the
number of individuals in a population that contribute their genes to
the next generation) that is below the level at which inbreeding
depression has been observed to occur (Stiver et al. 2008, p. 479).
Since the remaining Gunnison sage-grouse satellite populations are
smaller than the San Miguel population, they are likely small enough to
induce inbreeding depression, and thus could be losing adaptive
potential (Stiver et al. 2008, p. 479).
Population structure of Gunnison sage-grouse was investigated using
mitochondrial DNA sequence (mtDNA, maternally-inherited DNA located in
cellular organelles called mitochondria) and nuclear microsatellite
data from six geographic areas (Crawford, Gunnison Basin, Curecanti
area of the Gunnison Basin, Monticello-Dove Creek, Pi[ntilde]on Mesa,
and San Miguel Basin) (Oyler-McCance et al. 2005, entire). The Cerro
Summit-Cimarron-Sims Mesa population was not included in the analysis
due to inadequate sample sizes. The Poncha Pass population also was not
included as it is composed of individuals translocated from Gunnison
Basin. Levels of genetic diversity were highest in the Gunnison Basin,
which had more alleles and many but not all of the alleles present in
other populations. All other populations had much lower levels of
diversity. The lower diversity levels were thought to be the result of
small population sizes and a high degree of geographic isolation
(Oyler-McCance et al. 2005, entire).
Collectively, the smaller populations contained 24 percent of the
genetic diversity of the species. Individually, each of the satellite
populations may not be crucially important genetically to the survival
of the species, but collectively it is reasonable to assume that 24
percent of the genetic diversity is important to the future rangewide
survival and adaptability of the species. Some of the genetic makeup
contained within the satellite populations (with the potential
exception of the Poncha Pass population since it consists of birds from
the Gunnison Basin) may be critical to maintaining adaptability in the
face of issues such as climate change or other environmental change.
All populations sampled were found to be genetically discrete units
(Oyler-McCance et al. 2005, p. 635), so the loss of any of them would
result in a decrease in genetic diversity of the species. In addition,
having multiple populations across a broad geographic area (population
redundancy) provides insurance against catastrophic events, such as
prolonged drought, and the aggregate number of individuals across all
populations increases the probability of demographic persistence and
preservation of overall genetic diversity by providing an important
genetic reservoir (GSRSC 2005, p. 179). The satellite populations are
important to the long-term viability of Gunnison sage-grouse because
they: (1) Increase species abundance rangewide; (2) minimize the threat
of catastrophic events to the species since the populations are widely
distributed across the landscape; and (3) provide additional genetic
diversity not found in the Gunnison Basin (GSRSC 2005, p. 199).
Habitat loss and decline can lead to range contraction and
population extinction (see Factor A). As a species' range contracts and
distances between populations increase, opportunities for gene flow are
reduced. Historically, the Monticello-Dove Creek, San Miguel, Crawford,
and Pi[ntilde]on Mesa populations were larger and were connected
through more contiguous areas of sagebrush habitat. The loss and
fragmentation of sagebrush habitat between the late 1950s and the early
1990s led to the current isolation of these populations, which is
reflected in low amounts of gene flow and isolation by distance (Oyler-
McCance et al. 2005, p. 635). However, Oyler-McCance et al. (2005, p.
636) noted that a few individuals in their analysis appeared to have
the genetic characteristics of a population other than their own,
suggesting they were dispersers from a different population. Two
probable dispersers were individuals moving from the San Miguel Basin
population into Monticello-Dove Creek and Crawford. The San Miguel
population itself appeared to have a mixture of individuals with
differing probabilities of belonging to different clusters. This
information suggests that the San Miguel population may act as a
conduit of gene flow among the satellite populations surrounding the
larger Gunnison Basin population. Additionally, another potential
disperser into Crawford was found from the Gunnison Basin (Oyler-
McCance et al. 2005, p. 636). This result is not surprising given their
close geographic proximity. The genetic makeup of the outlying
Monticello-Dove Creek and Pi[ntilde]on Mesa populations were
consistently distant from all other populations and from each other.
This and other tests indicated that geographic distances (or
separation) are correlated with the genetic distance between
populations of Gunnison sage-grouse (Oyler-McCance et al. 2005, p.
635).
Movement of local (not translocated) birds between the Monticello
and Dove Creek populations has not been documented. In 2011, five
translocated and radio-collared hens released in Dove Creek during the
spring were recorded in Utah during the breeding season (Messmer 2013,
p. 4). These movements may not be representative of typical behavior of
local birds, however, since translocated birds have been known to make
erratic or irregular movements following translocation.
While we acknowledge there are likely benefits from translocating
Gunnison sage-grouse from the Gunnison Basin to satellite populations
(see Scientific Research and Related Conservation Efforts in Factor B),
such efforts may have diluted the genetic makeup and potentially unique
characteristics of some of the receiving populations (e.g.,
Pi[ntilde]on Mesa, which is thought to be more unique genetically).
However, more research is needed to determine the success of
translocations, what the effect is on genetic make-up within
populations, and whether translocations should continue in all
satellite populations.
In northwestern Colorado, dispersal of juvenile male greater sage-
grouse had more influence on genetic diversity in populations than
dispersal of females (Thompson 2012, p. 256). Based on observed bird
dispersal, gene flow and connectivity in greater sage-grouse can likely
be maintained for populations 5 to 10 km apart (most dispersals were
less than 10 km) and possibly as far as 20 km (the maximum dispersal
distance of birds studied) (Thompson 2012, p. 285-286). If genetic
diversity and dispersal mechanisms operate similarly in Gunnison sage-
grouse populations (typical dispersals less than 10 km), it is unlikely
that gene flow and genetic diversity is currently being maintained due
to the distance between these populations. The seven Gunnison sage-
grouse populations are generally more than 10 km apart from each other
(based
[[Page 69290]]
on mapped occupied habitat), and most are 20 km apart or more (Figure
1).
Lowered hatching success is a well-documented indicator of
inbreeding in wild bird populations. In one study, it was suggested
that the low hatching success rates observed in Gunnison sage-grouse
may have been due to inbreeding depression (Stiver et al. 2008, p. 479,
and references therein). Other bird species that had undergone genetic
bottlenecks have had similar hatchability rates. Independent of genetic
pressures or differences in a given population, some eggs fail to hatch
because they are infertile or simply do not develop fully. Based on a
review of sage-grouse research in Colorado, an estimated 10 percent of
eggs produced will likely fail to hatch, even in healthy populations
(CPW 2013b, p. 12). However, we expect that hatch failure rates would
likely increase above that level in smaller populations where
inbreeding is more likely to occur.
Effective Population Size and Population Viability Analyses
Effective population size (Ne) is an important parameter in
conservation biology. It is defined as the number of individuals
contributing their genes to the next generation. In technical terms,
effective population size is an idealized population size of breeding
adults that would experience the same rate of (1) loss of
heterozygosity (the amount and number of different genes within
individuals in a population), (2) change in the average inbreeding
coefficient (a calculation of the amount of breeding by closely related
individuals), or (3) change in variance in allele (one member of a pair
or series of genes occupying a specific position in a specific
chromosome) frequency through genetic drift (the fluctuation in gene
frequency occurring in an isolated population) as the actual population
(Wright 1930, entire).
The effective size of a population is often much less than its
actual size or number of individuals. As effective population size
decreases, the rate of loss of allelic diversity via genetic drift
increases. Two consequences of this loss of genetic diversity, reduced
fitness through inbreeding depression and reduced response to sustained
directional selection (``adaptive potential''), are thought to elevate
extinction risk (Stiver et al., 2008, p. 472 and references therein).
While no consensus exists on the population size needed to retain a
level of genetic diversity that maximizes evolutionary potential (i.e.,
the ability to adapt to local changes) for a given species, up to 5,000
greater sage-grouse may be necessary to maintain an effective
population size of 500 birds (Aldridge and Brigham, 2003, p. 30). Other
recent recommendations also suggest populations of at least 5,000
individuals to deal with evolutionary and demographic constraints
(Traill et al. 2009, p. 3, and references therein). While the
persistence of wild populations is usually influenced more by
ecological rather than by genetic effects, once populations are reduced
in size, genetic factors become increasingly important (Lande 1995, p.
318).
Population viability analysis (PVA) is a risk assessment tool used
to predict the relative probability of extinction for a species,
population, or various population sizes under different management
scenarios to aid in decision-making for conservation and management.
Fundamentally, population viability and persistence depends on a
population's growth rate (births and deaths) and the recruitment of
individuals through immigration and emigration. PVA does not predict
the real or absolute risk of extinction for a species or population,
only their relative extinction risk under various scenarios, and thus
should be interpreted and applied with caution. To date, three
population viability analyses or studies have been conducted for
Gunnison sage-grouse: (1) A PVA developed as part of the RCP in 2005 by
Dr. Phil Miller through CPW (GSRSC 2005, Appendix G); (2) a PVA
developed for the Service in 2005 by Dr. Edward Garton (Garton 2005,
entire); and (3) a demographic study and PVA developed by Dr. Amy Davis
at Colorado State University (Davis 2012, entire). Each of these
studies and their results are described in detail below.
RCP Population Viability Analysis
Dr. Phillip Miller prepared a population viability analysis (PVA)
for the Gunnison sage-grouse for CPW as part of the RCP (GSRSC 2005,
Appendix G). The purpose of this PVA was to assist the CPW in
evaluating the relative risk of extinction for each population under
the conditions at that time (i.e., the risk of extinction if nothing
changed), to estimate relative extinction probabilities and loss of
genetic diversity over time for various population sizes, and to
determine the sensitivity of Gunnison sage-grouse population growth
rates to various demographic parameters (GSRSC 2005, p. 169). The PVA
was used by the RCP as a tool to predict the relative, not absolute or
precise, probability of extinction for the different populations under
various management scenarios based on information available at that
time. The model did not incorporate certain factors including habitat
loss and fragmentation, density-dependent reproduction, effects of
disease, or inbreeding depression, all of which may affect the
demographic rates and, therefore, status of a given population (GSRSC
2005, p. 170). Furthermore, while Gunnison sage-grouse demographic data
were used where available, the PVA also applied greater sage-grouse
demographic data, as needed (GSRSC 2005, p. 169). We believe it is
appropriate to apply greater sage-grouse data where Gunnison sage-
grouse data are not available or limited. However, this may weaken
inferences in assessing the viability of Gunnison sage-grouse due to
the species' unique behavioral and genetic characteristics (Young et
al. 2000b, entire) and potentially different vital rates, such as
annual survival (Davis 2012, p. 63) and nesting success rates (Davis
2012, p. 11). In contrast, another more recent PVA applied only
Gunnison sage-grouse demographic data (Davis 2012, entire) (see Davis
Population Viability Analysis), and thus it is likely more reliable in
terms of assessing the viability of the species.
This 2005 PVA indicated that, in the absence of additional habitat
loss and fragmentation and the factors noted above, stable populations
in excess of 500 birds had an extinction risk of less than 5 percent
within the next 50 years following the study (that is, through 2055)
and may be considered ``secure'' (GSRSC 2005, p. 170; GSRSC 2005, p. G-
21). The PVA found that the probability of the Gunnison Basin
population going extinct within the next 50 years was less than
approximately 1 percent (GSRSC 2005, p. G-21). The Gunnison Basin
population was approximately 3,000 individuals around the time the PVA
was developed (2005). If the model were re-run, with approximately
3,978 birds as of 2014, the predicted risk of extinction would be even
lower due to this population increase (Phillips 2013, p. 2). This view
does not take into account, however, other new information that could
be incorporated into an updated model re-run, such as the Gunnison
sage-grouse demographic data collected by Davis (2012, entire). The
model concluded that the Gunnison Basin population, and therefore the
species, is likely to survive over the long term (GSRSC 2005, p. 179),
barring catastrophic events such as disease or prolonged drought
(assuming a degree of consistency of environmental influences on sage-
grouse demography) or a
[[Page 69291]]
significant reduction in carrying capacity through habitat loss.
In contrast, the analysis found that small populations (<25 to 50
birds) are at high risk of extinction within the next 50 years (through
the year 2055) (assuming some degree of consistency of environmental
influences on sage-grouse demography), even if these populations are
expected to increase over the long-term (GSRSC 2005, pp. 170 and G-27).
A stable population of 50 birds had an extinction probability of 59
percent within the next 50 years; a stable population of 25 birds had
an extinction probability of 86 percent within the next 50 years. The
analysis also found that the probability of extinction was higher yet
for declining populations of this size (GSRSC 2005, p. G-27). However,
the model found that augmentation of birds (approximately 10 birds
every five years) would considerably reduce the probability of
extinction (to near zero) for these smaller populations (GSRSC 2005,
pp. 176-179).
Based on the RCP PVA (GSRSC 2005, Appendix G), in the absence of
intervention such as translocating of birds, the Cerro Summit-Cimarron-
Sims Mesa (74 birds) and Dove Creek (24 birds) populations are
currently at high risk of extirpation (GSRSC 2005, pp. 168-179).
Likewise, the Poncha Pass population has remained below 50 birds since
1999, and has generally declined over this period (Figure 3),
indicating this population is also at high risk of extirpation, based
on this PVA. Zero birds were counted at leks in the spring of 2013 for
the Poncha Pass population. However, 17 birds were translocated into
the population in the fall of 2013, with 16 surviving in the spring of
2014 and 10 more birds were translocated in the spring of 2014 (see
Scientific Research and Related Conservation Efforts in Factor B).
Considerable translocation efforts from 2010 to 2013 have likely
contributed to increased population estimates in the Crawford and
Pi[ntilde]on Mesa populations (see Current Distribution and Population
Estimates and Trends; and Scientific Research and Related Conservation
Efforts). Without the recent increases in bird numbers, Crawford and
Pi[ntilde]on Mesa population would also likely be at serious risk of
population extinction (i.e., around 50 birds and a 59 percent or
greater probability of extinction), based on this PVA.
Garton Population Viability Analysis
To estimate population viability, Garton (2005, entire) analyzed
trends in abundance for Gunnison sage-grouse populations and the
species rangewide using male lek count data from the preceding 50 years
from CPW and the UDWR. Due to inconsistencies in data collection over
time, the analysis was conducted for two time periods--long-term lek
data collected since 1957 for CPW, and since 1976 for UDWR, through
2005; and short-term lek data from 1995-2005 when sampling
methodologies were standardized and became more consistent. Relative
population size from past years was calculated by setting the most
recent population estimate at the time (in 2005) to 100 and calculating
the previous years' population size relative to that, so that it could
be viewed as a percentage of the 2005 population level.
Garton's (2005, pp. 3-4) analysis indicated that the rangewide
population varied between a low of 40 percent of the 2005 lek count in
1991 and 1993; to a high of 140 percent of the 2005 lek count in 1969.
He suggested that unusual counts, which represented at least a 50
percent change in abundance, were preceded or followed by more typical
count indices, and that these outlier data probably reflect measurement
errors rather than actual changes population size. For instance, lek
count data collected for 2005 show a considerable increase in the
number of males attending leks, with an approximate 50 percent increase
from 2004 estimates of rangewide abundance. This aberration is thought
to be the result of unusual weather conditions during that period and,
consequently, possible double- or triple-counting of males across
multiple lek sites at various elevations (Garton 2005, pp. 2-3, and
references therein). Because of this, the analyses were conducted both
with and without 2005 data. Including the 2005 data in the long-term
analysis (since 1957) resulted in a slightly increasing population
trend; without the 2005 count data, the analysis showed a slightly
decreasing population trend, which Garton (2005, p. 4) suggested was a
better descriptor of observed trends in population estimates.
Statistical analyses of the Cerro Summit-Cimarron-Sims Mesa and Dove
Creek populations could not be completed due to low lek counts and
inconsistencies in sampling over time. Likewise, the small Poncha Pass
population was not analyzed because it had been surveyed for only 6
years and the population was augmented with birds from Gunnison Basin
during that time.
The long-term analysis (1957-2005) by Garton (2005, entire) found
that the rangewide population of Gunnison sage-grouse was stable,
neither increasing nor decreasing, during that time period. Annual
rates of change were highly variable, with some of that variability
likely attributed to different sampling methods rather than actual
population change. The shorter analysis period (1995-2005) yielded the
same results, although the variability was reduced, likely due to more
consistent data collection methods. Individual populations reflected
the trends in the rangewide analysis, in that some populations were
slightly increasing and some were slightly decreasing.
As observed in similar analyses conducted for the greater sage-
grouse (Connelly et al. 2004, entire), density-dependent models
appeared to more accurately describe observed population trends in
Gunnison sage-grouse. Garton's study suggested an apparent inverse
density-dependent pattern of population change in Gunnison sage-grouse,
resulting in a low probability (less than 1 percent) that the
population will decline to low abundances (below 25 percent of the 2005
population index), provided environmental factors (e.g., catastrophic
drought, disease, continuing habitat loss) do not reduce equilibrium
population size or increase the variability in population change
(Garton 2005, pp. 4-5).
Of the populations studied, Gunnison Basin and Pi[ntilde]on Mesa
showed slightly increasing trends in abundance of Gunnison sage-grouse;
San Miguel Basin, Crawford, and Monticello showed slightly decreasing
trends in abundance from 1995 to 2005 (Table 13 below). The short-term
analysis (1995-2005) indicated that the San Miguel Basin population was
declining rapidly, as much as a 10 percent decline per year, though
there was uncertainty in this prediction due to possible sampling
errors. Declines were also evident in the Monticello population.
Table 13--Summary of Population Trends for the Gunnison Sage-Grouse From
1995 to 2005 (Garton 2005, Entire)
[Values are the finite rate of change in the population, where 1 is no
change, numbers less than 1 indicate a decline, and numbers greater than
1 indicate an increase]
------------------------------------------------------------------------
Finite rate of
Population change 1995-
2005
------------------------------------------------------------------------
Gunnison Basin......................................... 1.05
Pi[ntilde]on Mesa...................................... 1.09
San Miguel Basin....................................... 0.902
Crawford............................................... 0.999
Monticello............................................. 0.99
Rangewide.............................................. 1.049
------------------------------------------------------------------------
Six peer reviewers evaluated the report by Garton (2005, entire).
We received comments from five of the
[[Page 69292]]
reviewers, three generally favorable towards the report and its
conclusions and two expressing concerns regarding limitations in the
data sets, assumptions, and/or analyses. For example, one would have to
assume that habitat availability over time would remain stable in order
to conclude that Gunnison sage-grouse numbers are unlikely to
experience a decline in the future. Also, while the conclusions showed
that the number of males per lek remained relatively stable over time,
the proportion of leks on which males were counted appeared to have
declined, which could be indicative of population declines. Peer
reviewers also recommended that more appropriate statistical tests
would need to be applied to come to any conclusion about potential
population trends and that emphasis should be on an independent
analysis of each geographically isolated population because each
population exhibits independent population dynamics. Population trend
analyses were conducted on a population basis as well as rangewide.
There was concern expressed that habitat loss over time was not
accounted for, that population declines would go unnoticed, and that
population trends would appear far too optimistic.
Davis Demographic Study and Population Viability Analysis
The Davis PVA (2012, entire) utilized demographic data specific to
Gunnison sage-grouse populations and incorporated other variables such
as extreme weather, fire, disease, and predation known to affect
survival and reproduction rates in Gunnison sage-grouse. This is in
contrast to the RCP PVA (GSRSC 2005, Appendix G) which combined greater
and Gunnison sage-grouse demographic data and did not account for
environmental variation (fire, disease, predation) other than
simulating a 3-year drought resulting in increased mortality; and the
Garton PVA (Garton 2005, entire) which only examined lek count-based
population estimates and trends to estimate viability. To estimate and
project Gunnison sage-grouse population trends, Davis (2012, pp. 1, 18)
conducted a demographic study of the Gunnison Basin and San Miguel
populations, the two largest populations. CPW acknowledged that this
study represents the most current and longest set of demographic data
collected for Gunnison sage-grouse (Phillips 2013, p. 2). Demographic
parameters (survival and reproduction rates) from both populations
collected from 2005 to 2010 were used to estimate population size and
viability over the next 30 years (Davis 2012, p. 79). These demographic
data were combined with longer-term lek count data from 1996 to 2011
(lek count protocols were standardized in 1996 (GSRSC 2005, p. 46)) in
the Gunnison Basin to model that population. The purpose of the model
(i.e., an integrated model that combined the two datasets) was to
reduce potential weaknesses and biases in both datasets--high
variability and uncertainty with the lek count data, and the small
sample size of the shorter-term demographic data--thereby statistically
improving estimates and predictions (Davis 2012, pp. 125-126). Key
methods and findings of this study are summarized below.
The demographic component of the study found no apparent difference
in nest success rates or adult survival between the San Miguel and
Gunnison Basin populations (Davis 2012, p. 37). However, the results
may be due in part to the limited duration and small sample size of the
study, especially in the San Miguel population (Davis 2012, p. 92).
Nest success from 2005 to 2011 varied widely between 21 and 60 percent,
with an average of 39 percent (Davis 2012, p. 9). Contrary to
expectations, nest site vegetation characteristics did not have a
strong influence on nest success in the Gunnison Basin and San Miguel
populations (Davis 2012, p. 10). Temporal factors appeared to have the
greatest influence on nesting success, as earlier season nesting tended
to be more successful than later season nesting, and the longer that
incubation occurred, the greater the risk of nest failure (Davis 2012,
p. 1). No yearlings were observed in the San Miguel population during
the study (Davis 2012, p. 12).
Juvenile recruitment was also evaluated within and between the two
populations (Davis 2012, p. 27). Chick survival (hatching to 30 days of
age) was higher in the Gunnison Basin than the San Miguel population
(Davis 2012, p. 44). Although sample size in the San Miguel Basin was
small (eight chicks were studied), none survived to 30 days of age,
meaning no recruitment (survival of bird from hatching to breeding age)
occurred over a 4-year period (Davis 2012, p. 37). Of 282 chicks
studied in the Gunnison Basin, 124 (44 percent) survived to 30 days of
age (Davis 2012, pp. 37-38). A slight negative trend in chick survival
and stronger negative trend in juvenile survival in the Gunnison Basin
population occurred from 2005 to 2010 (Davis 2012, p. 27). Juvenile
recruitment declined from 26 percent in 2005 to 5 percent in 2010.
These results indicate that lower juvenile recruitment may be
contributing to the study's observed population declines in the
Gunnison Basin (birds from the San Miguel population were not included
in the juvenile survival analysis, as none survived to 31 days), and
that the population may not be as stable as has been suggested.
However, study results may be due to the limited sample size (duration)
of the study, and a longer study may indicate that declines observed
are fluctuations within a larger cyclical time series (Davis 2012, p.
38).
Adult and yearling survival rates were also analyzed within and
between the two populations. The effect of harsh winter conditions on
these demographic rates was also studied. Male survival rates were
lower during the lekking season (March--April), and female survival
rates were lower during the nesting and chick rearing season (May-
August) (Davis 2012, p. 55). Harsh winters (as indicated by above
normal snow depth), which occurred during 2007 and 2008 in the Gunnison
Basin, and during 2009 and 2010 in the San Miguel Basin, had minimal
effect on Gunnison sage-grouse survival (Davis 2012, pp. 55, 65). The
study found no differences in adult and yearling survival between the
San Miguel and Gunnison Basin populations. This was surprising, given
the apparent decline in bird numbers in the San Miguel population based
on lek count estimates, suggesting declines are likely due to reduced
recruitment and juvenile survival rates rather than reduced adult
survival (Davis 2012, p. 66).
The Davis PVA applied the derived baseline demographic data for
survival and reproduction rates to estimate population growth of
Gunnison sage-grouse, including an analysis of viability and extinction
risk. The study also evaluated the effects of bird translocation
efforts on the survival of the San Miguel (destination) population and
the Gunnison Basin (source) population (Davis 2012, p. 79, 87). Based
on the six years of demographic data collected from 2005 to 2010 in the
Gunnison Basin, and four years of demographic data collected from 2007
to 2010 in the San Miguel population, deterministic population models
indicated that both the Gunnison Basin and San Miguel populations were
declining during those time periods, with more pronounced declines in
the latter (Davis 2012, p. 87). For the four years when data was
collected in both populations (2007-2010), population growth rates
([lambda]) ranged from 0.65 to 0.91 in the Gunnison Basin, and 0.52 to
0.68 in the San Miguel population (Davis 2012, pp. 87-88). A [lambda]
value of 1.0 indicates a stable population; values
[[Page 69293]]
less than 1.0 indicate a declining population; and values greater than
1.0 indicate an increasing population. Of the six years of study (2005-
2010) in the two populations combined, population growth rates ranged
from 0.65 in 2010, to 1.14 in 2006 (Davis 2012, p. 134). Of the six
years of study in the Gunnison Basin alone (from 2005 to 2010), four of
these years indicated population declines and two years indicated
population growth (Davis 2012, p. 87).
Incorporating environmental stochasticity (variability in
population growth rates due to external factors such as weather, fire,
disease, and predation) and demographic stochasticity (variability in
population growth rates due to survival and reproduction rates), model
simulations also predicted population declines in the future (Davis
2012, pp. 105-106). Combining the six years of demographic data (2005
to 2010) from both populations, environmental stochastic simulations
resulted in a minimum extinction time of 31 years for both populations.
Minimum extinction time is the earliest time at which population
extinction occurred among the various modeled simulations in this
study. This is in contrast to the mean extinction time, the average
time of all modeled simulations at which population extinction
occurred. Mean or expected extinction time in this PVA for the Gunnison
Basin population is 58 years (Davis 2012, p. 137). Davis also (2012, p.
92) noted, however that if the study had been conducted just a few
years earlier or later, a different trend across time could have
resulted, because it was based on a 6-year period of time when the
population was experiencing a slight decline.
Assuming and incorporating an additional year of increasing,
constant, or declining population growth into these simulations to
model demographic stochasticity resulted in minimum extinction times of
41, 29, and 20 years, respectively for both populations combined (Davis
2012, p. 88). Additionally, the extinction risk (i.e., proportion of
simulations that went extinct within 30 years) was substantially larger
for San Miguel than for Gunnison Basin (0.53 for San Miguel, 0 for
Gunnison Basin) (Davis 2012, p. 88). Demographic stochastic simulations
for the Gunnison Basin population approached extinction, but none went
extinct over the 30-year period. Therefore, the estimated extinction
risk was 0.00 for the Gunnison Basin population over this period,
indicating a low probability of extinction over the next 30 years due
to demographic stochasticity alone (Davis 2012, pp. 88, 106). However,
looking further out, demographic stochastic simulations resulted in
mean extinction time of 58 years for the Gunnison Basin population,
without removing any birds for translocation efforts (removal of birds
decreased the mean extinction time) (Davis 2012, pp. 111, 137). These
demographic projections indicate the Gunnison Basin population is
relatively stable, but may be in decline (Davis 2012, p. 137-138).
However, see discussion involving the integrated model below.
Additionally, Davis also (2012, p. 92) noted that if the study had been
conducted just a few years earlier or later, a different trend across
time could have resulted, because it was based on a 6-year period of
time when the population was experiencing a slight decline.
Davis (2012, p. 96) also examined the periodic removal of birds
from the Gunnison Basin and whether a long-term translocation effort
would be sustainable since it could negatively affect the viability of
that population depending upon the number of birds translocated each
time and the frequency of translocations. Results indicated that, in
general, more frequent removal of birds from the source population had
a greater effect than removing a larger number less frequently.
If trends observed during the study continue into the future,
declines in both the San Miguel and Gunnison Basin populations are
expected to occur over the next 30 years (i.e., by 2042). However, the
results may be due in part to the limited duration and small sample
size of the study (Davis 2012, p. 92) (see also discussion involving
the integrated model below.) Davis (2012, pp. 89, 93) indicated that
adult survival may be the most important vital rate for steeply
declining populations, such as the San Miguel population, while
juvenile survival is most important for increasing or slightly
declining populations, such as the Gunnison Basin population.
An evaluation of translocation efforts indicated that more frequent
translocations would increase population persistence in the San Miguel
population, but with negative effects on the Gunnison Basin, or source,
population (decreased mean and minimum extinction times) (Davis 2012,
p. 91). Frequent translocations would avoid extinction of the San
Miguel population, based on the population models, although this would
mean maintaining a population of translocated birds (Davis 2012, p.
96). Furthermore, juvenile recruitment in that population would need to
be improved for the population to persist on its own (Davis 2012, p.
97).
To further evaluate population viability, Davis (2012, pp. 125-126)
combined baseline demographic data and lek count data from the Gunnison
Basin in a separate, integrated population model. Short-term
demographic data were combined with long-term lek count data from 1996
to 2011 (16 years) to reduce potential weaknesses in both datasets--
high variability and uncertainty with the lek count data and small
sample size of the demographic data--with the goal of statistically
improving estimates and predictions (Davis 2012, pp. 125-126). Lek
count protocols were standardized in 1996 (GSRSC 2005, p. 46); prior to
that time, data showed high variability and uncertainty and, therefore,
were not included in the analysis (Davis 2012, pp. 139, 143). The
analysis indicated that the Gunnison Basin population has declined
slightly over the past 16 years, with a mean annual population growth
rate of 0.94, with a 95 percent confidence interval of 0.83 to 1.04.
This growth range was found to be narrower (more accurate) than growth
estimates based on lek count data alone (0.79-1.92, with a mean of
1.04) or demographic data alone (0.65-1.14, with a mean of 0.89) (Davis
2012, p. 134). On average, the population appeared to be relatively
stable over the 16-year period, but the end of the time series showed a
slight decline (Davis 2012, p. 138). However, it was noted that results
of the study are preliminary, and further testing is needed to validate
the model (Davis 2012, p. 140).
More recently, incorporating an additional year of lek count data
into their integrated model (1996-2012), Davis et al. (in press) states
that the Gunnison Basin population is ``slightly declining'' and the
growth rate of this population has been variable, but is ``near
stable.'' The updated growth rate was calculated to be 0.988, with the
95 percent confidence interval also including stable and slightly
increasing growth rates (0.893 to 1.079).
Davis (2012, p. 139) cautioned against making conclusions and
population estimates based on lek count data collected prior to 1996,
due to the data's high variability and uncertainty. The number of lek
areas surveyed in Colorado increased beginning in 1996, when lek count
protocols were standardized (GSRSC 2005, p. 46), indicating increases
in abundance that may not be accurate (Davis 2012, p. 143). Even
standardized lek counts show high variability and uncertainty and,
therefore, should not be used alone to estimate or project Gunnison
sage-
[[Page 69294]]
grouse populations (Davis 2012, p. 165). Demographic data showed
consistently lower population growth rates than indicated by
standardized lek count data, suggesting an imperfect relationship
between the two data types. Lek count data sometimes resulted in
extremely high values of population growth that were not realistic
based on demographic analyses (Davis 2012, pp. 134, 136).
Discussion of All Population Viability Analyses
The most current and comprehensive demographic study and population
viability analysis for Gunnison sage-grouse (Davis PVA) indicated that
the San Miguel population is showing a decline, and the Gunnison Basin
population has been relatively stable over the past 16 years (up to
2011), with a slight decline towards the end of the study period (Davis
2012, entire). Incorporating environmental and demographic
stochasticity into the models also predicted declines in both of these
populations in the future (Davis 2012, pp. 105-106). Combining
demographic data from both populations, environmental stochastic
simulations resulted in a minimum extinction time of 31 years (i.e.,
2043) for the two populations combined (Davis 2012, p. 88). For the San
Miguel population, demographic stochastic simulations indicated a high
probability (0.53) of extinction over the next 30 years (2042) (Davis
2012, p. 88). Demographic stochastic simulations for the Gunnison Basin
population approached extinction over this period, but none went
extinct over the 30-year period (extinction risk of 0.00) (Davis 2012,
pp. 88, 106). However, looking further out, demographic simulations
resulted in a mean extinction time of 58 years for the Gunnison Basin
population (without removing any birds for translocation efforts)
(Davis 2012, pp. 111, 137), or by about 2070. Davis (2012, p. 92)
noted, however, that if the study had been conducted just a few years
earlier or later, a different trend across time could have resulted,
because it was based on a 6-year period of time when the population was
experiencing a slight decline.
The Davis PVA also suggested that the Gunnison Basin population may
not be as stable as previously thought (Davis 2012, p. 38). Based on an
integrated analysis of 16 years of lek count and demographic data, the
Gunnison Basin population may be declining slightly (Davis 2012, p.
137). Further, based on Davis's findings, we infer that the Gunnison
Basin population may not be as large as lek count-based estimates
suggest. Davis (2012, pp. 134, 136) found that lek count data resulted
in extremely high values of population growth that were not realistic
based on demographic data for the Gunnison Basin population. Davis 2012
(p. 138) and Davis et al. in press state, however, that the Gunnison
Basin population has shown only a slight decline since 1996, which they
also describe as currently being ``relatively stable'' and ``near-
stable.''
In contrast, the earliest population viability analysis for
Gunnison sage-grouse from the RCP (GSRSC 2005, Appendix G) indicated a
low probability of extinction (less than 1 percent) for the Gunnison
Basin population (with approximately 3,000 birds at the time); and a
low extinction risk (less than 5 percent) for smaller populations (more
than 500 birds) over the next 50 years (i.e., to 2055) (GSRSC 2005, p.
G-21). This model concluded that the Gunnison Basin population, and
therefore the species, is likely to survive over the long term (GSRSC
2005, p. 179). We are concerned, however, with the reliability of the
estimated extinction probabilities and conclusions from this study, for
reasons noted above and as follows. Applying the extinction
probabilities from this study, some satellite populations would have
been considered relatively secure in recent years based on estimated
abundance. For example, the San Miguel and Monticello populations, with
approximately 200 to 400 birds or more in recent years (see Figure 3),
would have had a relatively low risk of extinction over the 50 years
ending in 2055 according to the RCP PVA. However, these populations
have declined since 2005 (Figure 3; also see Relevant Species
Information in this section) to a point that their survival and long-
term viability is currently at risk. This suggests that the extinction
risk for individual Gunnison sage-grouse populations, including the
Gunnison Basin, and the entire species is higher than was estimated in
this study (i.e., the study may have overestimated the viability of
Gunnison sage-grouse). This PVA combined greater and Gunnison sage-
grouse demographic data and did not account for environmental variation
(such as fire, disease, and predation), in contrast to the Davis PVA.
Long-term (1957-2005) and short-term analyses (1996-2005) from
Garton (2005, entire) found that the rangewide population of Gunnison
sage-grouse was generally stable, neither increasing nor decreasing
during that time period. Accordingly, some populations were declining
and some were increasing. The study did not estimate extinction
probabilities. We are concerned with the current relevance of the
Garton (2005, entire) study, however, as nine additional years of lek
count data have become available since the study was conducted. These
new lek count data, combined with other data from 1996 to 2010 (per
Davis 2012, entire), provide a more precise estimate of population
levels and trends than from information that was available in 2005. As
discussed earlier, lek count protocols were first standardized in 1996
(GSRSC 2005, p. 46), and lek count data collected prior to that year
were prone to high variability and uncertainty (Davis 2012, p. 139).
Based on lek count population estimates, relatively stable trends in
the Gunnison Basin population 1996 to 2014 match that of the findings
in Garton (2005, entire). However, a relatively stable rangewide
population, as indicated by Garton (2005, entire), is not supported by
recent declines in several of the satellite populations from 1996 to
2014 (Figure 3; also see Relevant Species Information above). The
apparent rangewide stability of Gunnison sage-grouse under the 2005
Garton PVA is influenced primarily by the largest population (the
Gunnison Basin--about 63 percent of the species' range) (Figure 2).
However, based on overall declining trends in several of the satellite
populations (encompassing about 37 percent of the species' occupied
range; and 16 percent of the known birds), as well as the questions
raised by the Davis PVA regarding the long-term stability of the
Gunnison Basin population, we do not agree that the species is stable
rangewide. Finally, in contrast to the Davis PVA, the Garton PVA only
examined lek count-based population estimates and trends to estimate
viability, and did not consider demographic or environmental factors or
stochasticity.
Each of these population viability models has its own limitations
and weaknesses, as described above. Again, a PVA does not predict the
real or absolute risk of extinction for a species or population, only
their relative extinction risk under various scenarios, and thus should
be interpreted and applied with caution. Further, the available PVAs
for Gunnison sage-grouse have resulted in somewhat disparate findings.
The two earlier PVAs (GSRSC 2005, entire; Garton 2005, entire)
collectively suggest most Gunnison sage-grouse populations are
relatively stable and that the species is likely to persist into the
future, attributable primarily to the large size and apparently stable
trend of the
[[Page 69295]]
Gunnison Basin population. On the other hand, the Davis model (2012,
entire) showed that the second largest population, the San Miguel
population, is at risk of extinction, with 53 percent of model
simulations reaching extinction in the next 30 years (by 2042) (Davis
2012, p. 88), and that even the largest Gunnison Basin population is
declining with a mean extinction time of 58 years from now, or by about
2070, due to demographic stochasticity alone (Davis 2012, pp. 111,
137). Davis (2012, p. 92) noted, however, that if the study had been
conducted just a few years earlier or later, a different trend across
time could have resulted, because it was based on a 6-year period of
time when the population was experiencing a slight decline. Based on
recent population trend data and related information, we identified
concerns with the two earliest PVAs and their current relevance and
reliability for assessing the status of Gunnison sage-grouse now and in
the future.
For the reasons stated above and here, we find that Davis (2012,
entire) and Davis et al. (in press) represent the most current and best
available scientific information regarding the viability of Gunnison
sage-grouse. We recognize that absolute extinction probabilities
provided in the Davis PVA are uncertain. However, based on that study
(Davis 2012, entire), the survival and persistence of the San Miguel
population appears to be at risk, with a 53 percent chance of
extinction by about 2042. Based on this finding, it is reasonable to
assume that the viability of the remaining satellite populations is
also at similar risk due to their small size, though we recognize that
environmental, demographic, genetic, and other factors likely vary
between populations, and that these differences will influence survival
and viability rates. Due to demographic fluctuations alone, the Davis
PVA also indicated that the Gunnison Basin population's viability is at
risk in the future, with a mean extinction time of 58 years, or by
about 2070.
Resiliency, Redundancy, and Representation
In this section, we synthesize the information above to evaluate
resiliency, redundancy, and representation as they relate to the
viability of Gunnison sage-grouse. Resiliency refers to the capacity of
an ecosystem, population, or organism to recover quickly from
disturbance by tolerating or adapting to changes or effects caused by a
disturbance or a combination of disturbances. Redundancy, in this
context, refers to the ability of a species to compensate for
fluctuations in or loss of populations across the species' range such
that the loss of a single population has little or no lasting effect on
the structure and functioning of the species as a whole. Representation
refers to the conservation of the diversity of a species, including
genetic makeup.
Small population sizes, declining population trends, low genetic
diversity, geographic isolation, and overall low viability (see
preceding discussions in this section) indicate that long-term
persistence and evolutionary or adaptive potential are compromised in
the six satellite populations. This, in turn, suggests that resiliency
is very low in the satellite populations, meaning they are less likely
to tolerate or adapt to the changes and effects from current and future
threats (see discussions in Factors A through C, and E). For example,
drought conditions from 1999 through about 2003 (with residual effects
lasting through about 2005) were closely associated with reductions in
the sizes of all Gunnison sage-grouse populations (CDOW 2009b, entire;
CPW 2013c, p. 9) (Figures 2 and 3) and lower nest success (CPW 2013c,
p. 2). To date, most of the smaller satellite populations have not
rebounded from declines around that time (Figure 3) (see Drought and
Extreme Weather in this Factor E discussion below).
In contrast, resilience currently appears to be relatively high in
the Gunnison Basin population, likely due to a large effective
population. For instance, drought has coincided with declines in the
Gunnison Basin population (CDOW 2009b, entire; Figure 2), including
declines at many of the lek complex areas (USFWS 2013c, pp. 1-2), but
the population has since rebounded to pre-drought levels (see Drought
and Extreme Weather in this section below for a detailed discussion).
However, as the effects from drought, climate change, disease, and
other substantial threats increase in the future, it is uncertain
whether resilience in this population will be sufficient to offset
declines (see Drought and Extreme Weather (Factor E discussion below),
Climate Change (Factor A), and Disease (Factor C)). As discussed
earlier, model simulations of environmental and demographic
stochasticity (natural fluctuations) resulted in extinction of the
Gunnison Basin population in 31 years (minimum extinction time) and 58
years (mean extinction time), respectively. This analysis suggested the
Gunnison Basin population may not be as stable (i.e., resilient) as
previously thought (Davis 2012, entire) (see Davis Population Viability
Analysis in this Factor E analysis). Davis also (2012, p. 92) noted,
however, that if the study had been conducted just a few years earlier
or later, a different trend across time could have resulted, because it
was based on a 6-year period of time when the population was
experiencing a slight decline.
While population redundancy currently exists across the species'
range, the best available information indicates the six satellite
populations are at risk of extirpation in approximately 30 years (see
preceding discussions in this section). Maintaining multiple satellite
populations is important to the long-term viability of Gunnison sage-
grouse because they: (1) Increase species abundance rangewide; (2)
minimize the threat of catastrophic events to the species since the
populations are widely distributed across the landscape; and (3)
provide additional genetic diversity not found in the Gunnison Basin
(GSRSC 2005, p. 199). With the loss of any population, population
redundancy will be lowered, thereby decreasing the species' chances of
survival in the face of environmental, demographic, and genetic
stochastic factors and catastrophic events (extreme drought, fire,
disease, etc.). Therefore, multiple populations across a broad
geographic area are required to provide insurance against catastrophic
events, and the aggregate number of individuals across multiple
populations increases the probability of demographic persistence and
preservation of overall genetic diversity by providing an important
genetic reservoir (representation) (GSRSC 2005, p. 179).
Five physiographic zones or divisions are recognized in the
Gunnison Basin population area for the purposes of monitoring and
management actions (CSGWG 1997, pp. 6-7). It has been suggested that
these zones represent subpopulations, or relatively discrete breeding
populations, and that they provide adequate population redundancy and
insurance against environmental disturbances such as drought (CPW
2013c, pp. 2, 9-10; Gunnison County 2013a, pp. 137-138; 169-170;
Gunnison County 2013b, p. 43). In this rule (see Drought and Extreme
Weather in this Factor E analysis), we present information which
indicates that, while some local redundancy may exist in the Gunnison
Basin population, it is not at a large enough scale to withstand
environmental pressures. While geographic and microclimatic variation
in the Gunnison Basin likely provide some degree of local variation
and, perhaps, local population redundancy to resist environmental
pressures, past
[[Page 69296]]
drought has had apparently extensive impacts on this population, as
indicated by concurrent negative trends in the majority of lek
complexes (see Drought and Extreme Weather in this Factor E analysis).
This information suggests that population redundancy in the Gunnison
Basin is limited, and is inadequate at the landscape scale necessary to
withstand more environmental pressures than those experienced to date,
such as prolonged drought, climate change effects, disease, or any
combination of those threats.
As discussed above, representation across the species' range is
currently low due to apparently isolated populations and limited gene
flow. Genetic diversity is highest in the Gunnison Basin population,
but low in the studied satellite populations (Oyler-McCance et al.
2005, entire). If population sizes continue declining, genetic
diversity will likely decrease as well (see Genetic Risks above in this
Factor E analysis).
Based on the information above, we find that resiliency,
redundancy, and representation in Gunnison sage-grouse are inadequate
overall to ensure the species' long-term viability. In particular, the
best available information indicates population redundancy will be more
limited in the near future, due to the extirpation of one or more
satellite populations, thereby decreasing the species' chances of
survival in the face of limiting factors. Current and future threats to
the Gunnison Basin population (in particular, see Drought and Extreme
Weather (Factor E discussion below), Climate Change (Factor A), and
Disease (Factor C)) combined with the probable loss of one or more
satellite populations and overall reduction of range indicate the long-
term persistence of Gunnison sage-grouse is at risk.
Summary of Small Population Size and Structure
Negative effects on population viability, such as reduced
reproductive success or loss of genetic variation and diversity are a
concern as populations decline and become smaller or more isolated.
Small population size and population structure occur in all of the six
satellite populations, or across approximately 37 percent of occupied
range for the species (see Relevant Species Information in this
section). Lek count data for the last 19 years (1996 to 2014) as a
whole indicate that several satellite populations are in decline
(despite increases in numbers in some populations in the last several
years Figure 3). Integrating lek count data and demographic data, the
Gunnison Basin population, the largest population, may be declining
slightly and may not be quite as stable as previously thought (Davis et
al. in press; Davis 2012, pp. 134, 38). Furthermore, because lek count
data tend to overestimate populations (Davis 2012, pp. 134, 136) the
Gunnison Basin population may not be large as has been estimated.
Based on small effective population sizes, the satellite
populations are at risk of inbreeding depression and could be losing
evolutionary or adaptive potential (Stiver et al. 2008, p. 479). Lower
levels of genetic diversity were apparent in studied satellite
populations of Gunnison sage-grouse, thought to be the result of small
population sizes and a high degree of geographic isolation (Oyler-
McCance et al. 2005, entire). All satellite populations sampled were
found to be genetically discrete units (Oyler-McCance et al. 2005, p.
635), so their loss would result in a decrease in genetic diversity of
the species. The only population currently providing individuals for
translocation is the Gunnison Basin population; however, we believe
care should be taken to ensure that this population can sustain the
loss of individuals required by a long-term translocation program to
other populations.
Historically, the satellite populations were larger and better
connected through more contiguous areas of sagebrush habitat. The loss
and fragmentation of sagebrush habitat between the late 1950's and the
early 1990's led to the current isolation of these populations, as
indicated by the low amounts of gene flow and isolation by distance
(Oyler-McCance et al. 2005, p. 635). Genetic information suggests gene
flow is limited between all populations (Oyler-MCance et al. 2005,
entire) (see Genetics discussion above in this section).
Available PVAs for Gunnison sage-grouse have resulted in somewhat
disparate findings, each with their own limitations or weaknesses. We
found that Davis (2012, entire) represents the best available
scientific information regarding the viability of Gunnison sage-grouse.
This represents the longest and most current demographic study and
population viability analysis for Gunnison sage-grouse. Based on that
study, the Gunnison Basin and San Miguel populations, the two largest
populations, are declining, with more pronounced declines in the latter
(Davis 2012, p. 87). The survival and persistence of the San Miguel
population, and likely the smaller satellite populations as well,
appear to be at risk in the near future. Though we expect the Gunnison
Basin population will persist longer than the satellite populations,
Davis (2012, entire) indicated that its future viability is also at
risk due to natural environmental and demographic fluctuations.
Small population size, declining population trends, and apparent
isolation indicate long-term population persistence and evolutionary
potential (i.e., resiliency) are compromised in the satellite
populations. In general, while various natural factors would not limit
sage-grouse populations across large geographic scales under historical
conditions or in larger populations, they may contribute to local
population declines or extirpations when populations are small or when
weather patterns, habitats, or mortality rates are altered. Multiple
populations across a broad geographic area provide insurance against
catastrophic events (population redundancy), such as prolonged drought,
and the aggregate number of individuals across all populations
increases the probability of demographic persistence and preservation
of overall genetic diversity by providing an important genetic
reservoir (representation) (GSRSC 2005, p. 179). As discussed above,
the best available information indicates the viability of the six
satellite populations is currently at risk due to small population size
and structure, and those cover 37 percent of the species occupied
range. Loss of as much as 37 percent of the species' occupied range
would impact the species' overall viability. The cumulative effects of
ongoing and future threats, such as habitat loss (Factor A) and drought
(discussed below), will further contribute to declining and
increasingly isolated populations and, ultimately, smaller population
size and structure.
Based on the best available information, we determined that
resiliency, redundancy, and representation in Gunnison sage-grouse are
inadequate, or will be inadequate in the near term, to ensure the
species' long-term viability. The best available information indicates
population redundancy, in particular, will be limited or compromised in
the near term, due to the probable extirpation of one or more satellite
populations, thereby decreasing the species' chances of survival in the
face of limiting factors. The rangewide cumulative effects of ongoing
and future threats (Factors A through C, and E) will further compromise
resiliency, redundancy, and representation of the species. Current and
future threats to the Gunnison Basin population (in particular, see
Drought (Factor E discussion below), Climate Change
[[Page 69297]]
(Factor A), and Disease (Factor C)) combined with the probable loss of
satellite populations and overall reduction of range indicate the long-
term persistence of Gunnison sage-grouse is at risk.
Drought and Extreme Weather
Drought and extreme weather such as severe winters have the
potential to impact the survival and, therefore, persistence of
Gunnison sage-grouse. Drought is a common occurrence throughout the
range of the Gunnison and greater sage-grouse (Braun 1998, p. 148) and
is considered a universal ecological driver across the Great Plains
region (Knopf 1996, p. 147). Infrequent, severe drought may cause local
extinctions of annual forbs and grasses that have invaded stands of
perennial species, and recolonization of these areas by native species
may be slow (Tilman and El Haddi 1992, p. 263). Drought reduces
vegetation cover (Milton et al. 1994, p. 75; Connelly et al. 2004, p.
7-18), potentially resulting in increased soil erosion and subsequent
reduced soil depths, decreased water infiltration, and reduced water
storage capacity. Drought also can exacerbate other natural events such
as defoliation of sagebrush by insects. For example, approximately
2,544 km\2\ (982 mi\2\) of sagebrush shrublands died in Utah in 2003 as
a result of drought and infestations with the Aroga (webworm) moth
(Connelly et al. 2004, p. 5-11). Sage-grouse are affected by drought
through the loss of vegetative habitat components, reduced insect
production (Connelly and Braun 1997, p. 9), and increased risk of West
Nile virus infections as described in the Factor C discussion above.
These habitat component losses can result in declining sage-grouse
populations due to increased nest predation and early brood mortality
associated with decreased nest cover and food availability (Braun 1998,
p. 149; Moynahan et al. 2007, p. 1781).
Greater sage-grouse populations declined during the 1930s period of
drought (Patterson 1952, p. 68; Braun 1998, p. 148). Drought conditions
in the late 1980s and early 1990s also coincided with a period when
sage-grouse populations were at historically low levels (Connelly and
Braun 1997, p. 8). Although drought has been a consistent and natural
part of the sagebrush-steppe ecosystem, drought impacts on sage-grouse
can be exacerbated when combined with other habitat impacts, such as
human developments, that reduce cover and food (Braun 1998).
Aldridge et al. (2008, p. 992) found that the number of severe
droughts from 1950 to 2003 had a weak negative effect on patterns of
greater sage-grouse persistence. However, they cautioned that drought
may have a greater influence on future sage-grouse populations as
temperatures rise over the next 50 years, and synergistic effects of
other threats affect habitat quality (Aldridge et al. 2008, p. 992).
Drought has also been shown to have a negative effect on chick survival
rates in greater sage-grouse (Aldridge 2005, entire), a key factor in
sage-grouse population reproduction, survival, and persistence (GSRSC
2005, p. 173). Populations on the periphery of the range may suffer
extirpation during a severe and prolonged drought (Wisdom et al. 2011,
pp. 468-469). In eastern Nevada, annual recruitment of greater sage-
grouse was higher in years with higher precipitation, based on annual
precipitation, annual rainfall, and average winter snow depth.
Likewise, greater sage-grouse population growth was positively
correlated with annual rainfall and mean monthly winter snowpack in the
study area. Annual survival of adult male greater sage-grouse was
negatively affected by high summertime temperatures (i.e., higher
survival rates occurred in years with relatively low maximum
temperatures) (Blomberg et al. 2012, pp. 7, 9). In contrast, adult
survival rates of Gunnison sage-grouse in the Gunnison Basin were not
apparently influenced by drought conditions in 2005 (CPW 2013c, p. 9;
Davis 2012, p. 55).
Drought conditions from 1999 through about 2003 (with residual
effects lasting through about 2005) were closely associated with
reductions in the sizes of all populations of Gunnison sage-grouse
(CDOW 2009b, entire; CPW 2013c, p. 9) (Figures 2 and 3) and lower nest
success (CPW 2013c, p. 2). The driest summer on record in the Gunnison
Basin occurred in 2002 (Gunnison County 2013a, pp. 112, 141). Based on
population trends from lek count data, the Gunnison Basin population
declined by about 30 percent from 2001 to 2003, but has since rebounded
to pre-drought numbers (USFWS 2013c, p. 1; Figure 2). Therefore, larger
populations of Gunnison sage-grouse may be capable of enduring moderate
or severe, but relatively short-term, drought. However, to date, most
of the smaller satellite populations have not rebounded from declines
around that time (Figure 3). This information highlights the potential
significance of drought and its influence on Gunnison sage-grouse
populations. It also indicates that resiliency is currently limited in
the satellite populations (see Resiliency, Redundancy, and
Representation). The small sizes of the satellite populations of
Gunnison sage-grouse make them particularly sensitive to stochastic and
demographic fluctuations, and this vulnerability is intensified by
drought (GSRSC 2005, p. G-22).
Overall, habitat appeared to be negatively affected by drought
conditions across a broad area of the Gunnison sage-grouse's range from
1999 through about 2003, though those effects varied by population area
(see our April 18, 2006, finding (71 FR 19954) for a detailed
discussion). Defoliation and mortality of sagebrush plants, and the
loss of grass and forb understories, was reported in 2003 across the
range of Gunnison sage-grouse (GSRSC 2005, p. 143, and references
therein), and in 2013 in the Gunnison Basin and Dry Creek Basin area of
the San Miguel population (CPW 2013c, p. 10, and references therein).
However, the reduction of sagebrush density, allowing for greater
herbaceous growth and stimulating the onset of sagebrush seed crops,
may have been beneficial to sagebrush habitats in certain areas over
the long term (GSRSC 2005, p.143; CPW 2013c, p. 10). Nonetheless, as
indicated by declining Gunnison sage-grouse populations during and
following drought periods, the negative impacts of drought appear to
outweigh any positive effects.
The above information indicates that regional drought has operated
at large enough scales to impact all populations of Gunnison sage-
grouse. Furthermore, it appears that past drought has had broad-scale,
measurable impacts on even the Gunnison Basin population, despite its
larger geographic area and population size. Figure 4 below shows
changes in high male sage-grouse counts at lek complexes in the
Gunnison Basin from 2001 to 2003. Based on lek count data, the largest
declines in the Gunnison Basin occurred during this time (Figure 2). Of
25 total lek complexes in the Gunnison Basin (not including leks where
no birds were observed or where counts did not occur), approximately 68
percent declined from 2001 to 2003, including many of the larger
complex areas with typically more birds. The largest lek complex in the
Gunnison Basin, Ohio Creek, declined by about 34 percent, from 530
birds in 2001 to 348 birds in 2003 (USFWS 2013c, pp. 1-2). The eight
lek complexes that remained stable or increased during this period (32
percent of total lek complexes) were typically smaller lek complexes
with fewer birds
[[Page 69298]]
(Lost Canyon, Gold Basin, Iola, North Parlin, and Sugar Creek); or, if
larger, only minor increases in bird numbers were observed (Antelope,
Hartman Gulch, Eagle Ridge) (USFWS 2013c, p. 3).
[GRAPHIC] [TIFF OMITTED] TR20NO14.003
Figure 4. Change in High Male Counts at Lek Complexes \a\ in the
Gunnison Basin From 2001 to 2003 (USFWS 2013c, pp. 1-2) \b\
[[Page 69299]]
While geographic and microclimatic variation in the Gunnison Basin
likely provides a degree of local variation and, perhaps, local
population redundancy to resist environmental pressures, past drought
had apparent widespread impacts on this population, as indicated by
negative trends in the majority of lek complexes during that time. This
suggests that population redundancy in the Gunnison Basin is limited,
and is inadequate at the landscape scale necessary to withstand more
substantial environmental pressures such as prolonged drought, climate
change effects, disease, or a combination of those threats. The drought
from 2001 to 2003 was severe but relatively short in duration. More
severe, prolonged, or frequent drought would likely have more serious
impacts. The species' apparent sensitivity to drought effects in all
populations, including the Gunnison Basin and across most lek complexes
in that population, suggests the species would have limited capacity to
withstand or adapt to more significant drought and the interacting
effects of climate change, disease, and other threats. Drought is also
discussed under the Climate Change (Factor A); and Resiliency,
Redundancy, and Representation (Factor E) sections.
Harsh or severe winters appear to have minimal influence on
Gunnison sage-grouse survival. Davis (2012, p. 55) evaluated the effect
of harsh winter conditions (as indicated by above normal snow depth) on
adult and yearling survival rates in the Gunnison Basin and San Miguel
populations. The winter of 2007 to 2008 was one of the most severe
winters on record in the Gunnison Basin, with snow depths that exceeded
records for all but 2 winters in the last 50 years (CPW 2013c, p. 2;
Gunnison County 2013a, p. 112). Severe winter conditions during 2007
and 2008 in the Gunnison Basin, and during 2009 and 2010 in the San
Miguel Basin, had minimal effect on Gunnison sage-grouse survival in
both populations; and, in the Gunnison Basin, the highest nesting
success during the study was observed the following spring (Davis
(2012, p. 55; CPW 2013c, p. 2).
Data are not available to evaluate whether the observed population
declines are due to drought alone. Drought likely intensifies other
stressors such as predation (Factor C), invasive plants (Factor A), and
fire (Factor A). However, based on the best available information,
drought has contributed to substantial declines in all Gunnison sage-
grouse populations. Therefore, we conclude that drought is a
substantial threat to Gunnison sage-grouse rangewide, both now and into
the future.
Recreation
Nonconsumptive recreational activities can degrade wildlife
resources, water, and the land by distributing refuse, disturbing and
displacing wildlife, increasing animal mortality, and simplifying plant
communities (Boyle and Samson 1985, pp. 110-112). Sage-grouse response
to disturbance may be influenced by the type of activity, recreationist
behavior, predictability of activity, frequency and magnitude, timing,
and activity location (Knight and Cole 1995, p. 71). We do not have any
published literature concerning measured direct effects of recreational
activities on Gunnison or greater sage-grouse, but can infer potential
impacts on Gunnison sage-grouse from studies on related species and
from research on nonrecreational activities. Displacement of male
sharp-tailed grouse has been reported at leks due to human presence,
resulting in loss of reproductive opportunity during the time of
disturbance (Baydack and Hein 1987, p. 537). Female sharp-tailed grouse
were observed at undisturbed leks while absent from disturbed leks
during the same time period (Baydack and Hein 1987, p. 537).
Disturbance of incubating female sage-grouse could cause displacement
from nests, increased predator risk, or loss of nests. Disruption of
sage-grouse during vulnerable periods at leks, or during nesting or
early brood-rearing could affect reproduction or survival (Baydack and
Hein 1987, pp. 537-538).
Recreational use of off-highway vehicles (OHVs) is one of the
fastest-growing outdoor activities. In the western United States,
greater than 27 percent of the human population used OHVs for
recreational activities between 1999 and 2004 (Knick et al. 2011, p.
217). Knick et al. (2011, p. 219) reported that widespread motorized
access for recreation facilitated the spread of predators adapted to
humans and the spread of invasive plants. Any high-frequency human
activity along established corridors can affect wildlife through
habitat loss and fragmentation (Knick et al. 2011, p. 219). The effects
of OHV use on sagebrush and sage-grouse have not been directly studied
(Knick et al. 2011, p. 216). However, Gunnison sage-grouse local
working groups and conservation plans considered recreational uses,
such as off-road vehicle use and biking, to be a risk factor in many
areas (see Factor D discussion, Multi-County and Rangewide Efforts).
Recreation from OHVs, hikers, mountain bikes, campers, snowmobiles,
bird watchers, and other sources has affected many parts of the range,
especially portions of the Gunnison Basin and Pi[ntilde]on Mesa
population areas (BLM 2005a, p. 14; BLM 2005d, p. 4; BLM 2009a, p. 36).
These activities can result in abandonment of lekking activities and
nest sites by Gunnison sage-grouse, energy expenditure reducing
survival, and greater exposure to predators (GSRSC 2005).
Recreation is a significant use on lands managed by BLM (Connelly
et al. 2004, p. 7-26). For example, recreational activities within the
Gunnison Basin are widespread, occur during all seasons of the year,
and have expanded as more people move to the area or travel there to
recreate (BLM 2009a, pp. 36-37). Four wheel drive, OHV, motorcycle, and
other mechanized travel has been increasing rapidly. The number of
annual OHV registrations in Colorado increased from 12,000 in 1991 to
131,000 in 2007 (BLM 2009a, p. 37). Recreational activities can have
direct and indirect impacts to the Gunnison sage-grouse and their
habitat (BLM 2009a, p. 36). The Grand Mesa, Uncompaghre, and Gunnison
(GMUG) National Forest is the fourth most visited National Forest in
the Rocky Mountain Region of the USFS (Region 2), and is the second
most heavily visited National Forest on the western slope of Colorado
(DEIS Gunnison Basin Federal Lands Travel Management 2009, p. 137).
However, it is unknown what percentage of the visits occurs within
Gunnison sage-grouse habitat on the Gunnison Ranger District (DEIS
Gunnison Basin Federal Lands Travel Management 2009, p. 137). With
human populations expected to increase in towns and cities within and
adjacent to the Gunnison Basin and nearby populations (see Factor A
analysis), the impacts to Gunnison sage-grouse from recreational use
will continue to increase.
The BLM, USFS, CPW, and Gunnison County currently close 36 roads at
47 closure points in the Gunnison Basin to all motorized traffic from
March 15 to May 15 to minimize impacts during the breeding season. Six
road closures by the USFS extend to June 15 to protect nesting Gunnison
sage-grouse. These closures limit motorized access to all known leks
and adjacent habitats on public lands in the Gunnison Basin (Gunnison
County 2013a, pp. 78, 127). While road closures may be violated in a
small number of situations, road closures are having a beneficial
effect on Gunnison sage-grouse through avoidance or minimization of
impacts
[[Page 69300]]
during the breeding season. Conservation measures from the CCA (BLM
2013b, entire), including road closure and reclamation, seasonal road
closures, and over-snow travel area closures during severe winters, are
expected to ameliorate impacts from some recreational activities on
Federal lands in the Gunnison Basin (see Conservation Programs and
Efforts Related to Habitat Conservation section in Factor A for more
details).
Dispersed camping occurs at a low level on public lands in all of
the population areas, particularly during the hunting seasons for other
species. However, we have no information indicating that these camping
activities are impacting Gunnison sage-grouse.
Domestic dogs accompanying recreationists or associated with
residences can disturb, harass, displace, or kill Gunnison sage-grouse.
Dogs, whether under control, on leash, or loose, have been shown to
result in significant disturbance responses by various wildlife species
(Sime 1999, entire, and references therein). The primary consequence of
dogs being off leash is harassment, which can lead to physiological
stress as well as the separation of adult and young birds, or flushing
incubating birds from their nest. However, we have no data indicating
that this activity is impacting Gunnison sage-grouse populations.
Recreational activities as discussed above do not singularly pose a
threat to Gunnison sage-grouse. However, there may be certain
situations where recreational activities are impacting local
concentrations of Gunnison sage-grouse, especially in areas where
habitat is already fragmented such as in the six satellite populations
and in certain areas within the Gunnison Basin.
Pesticides and Herbicides
Insects are an important component of sage-grouse chick and
juvenile diets (GSRSC 2005, p. 132 and references therein). Insects,
especially ants (Hymenoptera) and beetles (Coleoptera), can comprise a
major proportion of the diet of juvenile sage-grouse and are important
components of early brood-rearing habitats (GSRSC 2005, p. 132 and
references therein). Most pesticide applications are not directed at
control of ants and beetles. Insecticides are used primarily to control
insects causing damage to cultivated crops on private lands and to
control grasshoppers (Orthoptera) and Mormon crickets (Mormonius sp.)
on public lands.
Few studies have examined the effects of pesticides to sage-grouse,
but at least two pesticides have caused direct mortality of greater
sage-grouse as a result of ingestion of alfalfa sprayed with
organophosphorus insecticides (Blus et al. 1989, p. 1142; Blus and
Connelly 1998, p. 23). In one case, a field of alfalfa was sprayed with
methamidophos and dimethoate when approximately 200 greater sage-grouse
were present; 63 of these sage-grouse were later found dead, presumably
as a result of insecticide exposure (Blus et al. 1989; p. 1142, Blus
and Connelly 1998, p. 23). Both methamidophos and dimethoate remain
registered for use in the United States (Christiansen and Tate 2011, p.
125), but we found no further records of sage-grouse mortalities from
their use. In another case in 1950, rangelands treated with toxaphene
and chlordane bait to control grasshoppers in Wyoming resulted in game
bird mortality of 23.4 percent (Christiansen and Tate 2011, p. 125).
Forty-five greater sage-grouse deaths were recorded, 11 of which were
most likely related to the insecticide (Christiansen and Tate 2011, p.
125, and references therein). Greater sage-grouse who succumbed to
vehicle collisions and mowing machines in the same area also were
likely compromised from insecticide ingestion (Christiansen and Tate
2011, p. 125). Neither toxaphene nor chlordane has been registered for
grasshopper control since the early 1980's (Christiansen and Tate 2011,
p. 125, and references therein) and thus they are not a threat to
Gunnison sage-grouse.
Infestations of Russian wheat aphids (Diuraphis noxia) have
occurred in Gunnison sage-grouse occupied range in Colorado and Utah
(GSRSC 2005, p. 132). Disulfoton, a systemic organophosphate that is
extremely toxic to wildlife, was routinely applied to over a million
acres of winter wheat crops to control the aphids during the late
1980s. We have no data indicating there were any adverse effects to
Gunnison sage-grouse (GSRSC 2005, p. 132). More recently, an
infestation of army cutworms (Euxoa auxiliaries) occurred in Gunnison
sage-grouse habitat along the Utah-Colorado State line. Thousands of
acres of winter wheat and alfalfa fields were sprayed with insecticides
such as permethrin, a chemical that is toxic to wildlife, by private
landowners to control them (GSRSC 2005, p. 132), but again, we have no
data indicating any adverse effects to Gunnison sage-grouse.
Game birds that ingested sublethal levels of insecticides have been
observed exhibiting abnormal behavior that may lead to a greater risk
of predation (Dahlen and Haugen 1954, p. 477; McEwen and Brown 1966, p.
609; Blus et al. 1989, p. 1141). Wild sharp-tailed grouse poisoned by
malathion and dieldrin exhibited depression, dullness, slowed
reactions, irregular flight, and uncoordinated walking (McEwen and
Brown 1966, p. 689). Although no research has explicitly studied the
indirect levels of mortality from sublethal doses of insecticides
(e.g., predation of impaired birds), it was inferred to be the cause of
mortality among some study birds (McEwen and Brown 1966 p. 609; Blus et
al. 1989, p. 1142; Connelly and Blus 1991, p. 4). Both Post (1951, p.
383) and Blus et al. (1989, p. 1142) located depredated sage-grouse
carcasses in areas that had been treated with insecticides. Exposure to
these insecticides may have predisposed sage-grouse to predation. Sage-
grouse mortalities also were documented in a study where they were
exposed to strychnine bait used to control small mammals (Ward et al.
1942 as cited in Schroeder et al. 1999, p. 16). While we do not have
specific information on these effects occurring in Gunnison sage-
grouse, the effects observed in greater sage-grouse can be expected if
similar situations arise within Gunnison sage-grouse habitat.
Cropland spraying may affect populations that are not adjacent to
agricultural areas, given the distances traveled by females with broods
from nesting areas to late brood-rearing areas (Knick et al. 2011, p.
211). The actual footprint of this effect cannot be estimated, because
the distances sage-grouse travel to get to irrigated and sprayed fields
is unknown (Knick et al. 2011, p. 211). Similarly, actual mortalities
from insecticides may be underestimated if sage-grouse disperse from
agricultural areas after exposure.
Much of the research related to pesticides that had either lethal
or sublethal effects on greater sage-grouse was conducted on pesticides
that have been banned or have had their use restricted for more than 20
years due to their toxic effects on the environment (e.g., dieldrin).
We currently do not have any information to show that the banned
pesticides are having negative impacts to sage-grouse populations
through either illegal use or residues in the environment. For example,
sage-grouse mortalities were documented in a study where they were
exposed to strychnine bait used to control small mammals (Ward et al.
1942 as cited in Schroeder et al. 1999, p. 16). According to the U.S.
Environmental Protection Agency (EPA), above-ground uses of the
rodenticide strychnine were prohibited in 1988 and those uses remain
temporarily cancelled today. We do not know when, or if, above-ground
uses will be permitted to resume. Currently, strychnine is registered
for use only
[[Page 69301]]
below-ground as a bait application to control pocket gophers (Thomomys
sp.; EPA 1996, p. 4). Therefore, the current legal use of strychnine
baits is unlikely to present much of an exposure risk to sage-grouse.
No information on illegal use, if it occurs, is available. We have no
other information regarding mortalities or sublethal effects of
strychnine or other banned pesticides on sage-grouse.
Although a reduction in insect population levels resulting from
insecticide application can potentially affect nesting sage-grouse
females and chicks (Willis et al. 1993, p. 40; Schroeder et al. 1999,
p. 16), there is no information as to whether insecticides are
impacting survivorship or productivity of the Gunnison sage-grouse.
Use of insecticides to control mosquitoes is infrequent and
probably does not have detrimental effects on sage-grouse. Available
insecticides that kill adult mosquitoes include synthetic pyrethroids
such as permethrin, which are applied at very low concentrations and
have very low vertebrate toxicity (Rose 2004). Organophosphates such as
malathion have been used at very low rates to kill adult mosquitoes for
decades, and are judged relatively safe for vertebrates (Rose 2004).
Herbicide applications can kill sagebrush and forbs important as
food sources for sage-grouse (Carr 1968 in Call and Maser 1985, p. 14).
The greatest impact resulting from a reduction of either forbs or
insect populations is to nesting females and chicks due to the loss of
potential protein sources that are critical for successful egg
production and chick nutrition (Johnson and Boyce 1991, p. 90;
Schroeder et al. 1999, p. 16). A comparison of applied levels of
herbicides with toxicity studies of grouse, chickens, and other
gamebirds (Carr 1968, in Call and Maser 1985, p. 15) concluded that
herbicides applied at recommended rates should not result in sage-
grouse poisonings.
In summary, historically insecticides have been shown to result in
direct mortality of individuals, and also can reduce the availability
of food sources, which in turn could contribute to mortality of sage-
grouse. Despite the potential effects of pesticides, we could find no
information to indicate that the use of these chemicals, at current
levels, negatively affects Gunnison sage-grouse population numbers.
Schroeder et al.'s (1999, p. 16) literature review found that the loss
of insects can have significant impacts on nesting females and chicks,
but those impacts were not detailed. Many of the pesticides that have
been shown to have an effect on sage-grouse have been banned in the
United States for more than 20 years. We currently do not have any
information to show that either the illegal use of banned pesticides or
residues in the environment are presently having negative impacts to
Gunnison sage-grouse populations. While the reduction in insect
availability via insecticide application has not been documented to
affect overall population numbers in sage-grouse, it appears that
insect reduction, because of its importance to chick production and
survival, could be having as yet undetected negative impacts in
populations with low population numbers. At present, however, there is
no information available to indicate that either herbicide or
insecticide applications pose a threat to the species.
Contaminants
Gunnison sage-grouse exposure to various types of environmental
contaminants may potentially occur as a result of agricultural and
rangeland management practices, mining, energy development and pipeline
operations, and transportation of materials along highways and
railroads.
We expect that the number of sage-grouse occurring in the immediate
vicinity of wastewater pits associated with energy development would be
small due to the small amount of energy development within the species'
range, the typically intense human activity in these areas, the lack of
cover around the pits, and the fact that sage-grouse do not require
free standing water. Most bird mortalities recorded in association with
wastewater pits are water-dependent species (e.g., waterfowl), whereas
dead ground-dwelling birds (such as the sage-grouse) are rarely found
at such sites (Domenici 2008, pers. comm.). However, if the wastewater
pits are not appropriately screened, sage-grouse may have access to
them and could ingest water and/or become oiled while pursuing insects.
If these birds then return to sagebrush cover and die, their carcasses
are unlikely to be found as only the pits are surveyed.
A few gas and oil pipelines occur within the San Miguel population.
Exposure to oil or gas from pipeline spills or leaks could cause
mortalities or morbidity to Gunnison sage-grouse. Similarly, given the
network of highways and railroad lines that occur throughout the range
of the Gunnison sage-grouse, there is some potential for exposure to
contaminants resulting from spills or leaks of hazardous materials
being conveyed along these transportation corridors. We found no
documented occurrences of impacts to Gunnison sage-grouse from such
spills, and we do not expect they are a significant source of mortality
or threat to the species because these types of spills occur
infrequently and may involve only a small area within the occupied
range of the species.
Summary of Factor E: Other Natural or Manmade Factors
Based on the information above, we find that small population size
and structure is a threat to the six satellite populations of Gunnison
sage-grouse, both now and into the future. Although genetic
consequences of low Gunnison sage-grouse population numbers have not
been definitively detected to date, the results from Stiver et al.
(2008, p. 479) suggest that six of the seven populations may have
effective sizes low enough to induce genetic deterioration, and that
all seven could be losing adaptive potential. While some of these
consequences may be ameliorated by translocations, information
indicates the long-term viability of Gunnison sage-grouse is
compromised by this situation, particularly when combined with threats
discussed in other Factors. Therefore, we have determined that genetics
risks related to the small population size of Gunnison sage-grouse are
a threat to the species.
Available PVAs for Gunnison sage-grouse have resulted in somewhat
disparate findings, each with their own limitations or weaknesses. We
found that Davis (2012, entire) represents the best available
scientific information regarding the viability of Gunnison sage-grouse.
This represents the longest and most current demographic study and
population viability analysis for Gunnison sage-grouse. Based on that
study, the Gunnison Basin and San Miguel populations, the two largest
populations, are declining, with more pronounced declines in the latter
(Davis 2012, p. 87). The survival and persistence of the San Miguel
population, and likely the smaller satellite populations as well,
appear to be at risk in the near future. Though we expect the Gunnison
Basin population will persist longer than the satellite populations,
Davis (2012, entire) indicated that its future viability is also at
risk due to natural environmental and demographic fluctuations.
Small population size, declining population trends, and apparent
isolation indicate long-term population persistence and evolutionary
potential (i.e., resiliency) are compromised in the satellite
populations. In general, while various natural factors would not limit
sage-grouse populations across large
[[Page 69302]]
geographic scales under historical conditions or in larger populations,
they may contribute to local population declines or extirpations when
populations are small or when weather patterns, habitats, or mortality
rates are altered. Multiple populations across a broad geographic area
(population redundancy) provide insurance against catastrophic events,
such as prolonged drought, and the aggregate number of individuals
across all populations increases the probability of demographic
persistence and preservation of overall genetic diversity by providing
an important genetic reservoir (representation) (GSRSC 2005, p. 179).
As discussed, viability of the six satellite populations is currently
at risk, and those cover 37 percent of the species occupied range. Loss
of as much as 37 percent of the species' occupied range would impact
the species' overall viability. The cumulative effects of ongoing and
future threats, such as habitat loss (Factor A) and drought (discussed
above), will further contribute to declining and increasingly isolated
populations and, ultimately, smaller population size and structure.
Based on the best available information, we determined that
resiliency, redundancy, and representation in Gunnison sage-grouse are
inadequate, or will be inadequate in the future, to ensure the species'
long-term viability. The best available information indicates
population redundancy, in particular, will be limited or compromised in
the future, due to the probable extirpation of one or more satellite
populations, thereby decreasing the species' chances of survival in the
face of limiting factors. The rangewide cumulative effects of ongoing
and future threats (see discussions in Factors A through C, and E) will
further compromise resiliency, redundancy, and representation of the
species. Current and future threats to the Gunnison Basin population
(in particular, see Drought, Climate Change, and Disease sections)
combined with the probable loss of one or more satellite populations
and overall reduction of range indicate the long-term persistence of
Gunnison sage-grouse is at risk.
While sage-grouse have evolved with drought, population trends
suggest that drought is at least correlated with, and likely an
underlying cause of, observed declines. We found that drought is a
current and future threat to Gunnison sage-grouse. Based on the best
available information, pesticides are being used infrequently enough
and in accordance with manufacturer labeling such that they are not
adversely affecting populations of the Gunnison sage-grouse. The most
likely impact of insecticides on Gunnison sage-grouse is the reduction
of insect prey items. However, we could find no information to indicate
that use of insecticides, in accordance with their label instructions,
is a threat to Gunnison sage-grouse. We similarly do not have
information indicating that contaminants, as described above, are a
threat to the species.
Cumulative Effects From Factors A through E
Many of the threats described in this finding may cumulatively or
synergistically impact Gunnison sage-grouse beyond the scope of each
individual threat. For example, grazing practices inconsistent with
local ecological conditions alone may only affect portions of Gunnison
sage-grouse habitat. However, grazing practices inconsistent with local
ecological conditions, combined with invasive plants, drought, and
recreational activities may collectively result in substantial habitat
decline across large portions of the species' range. In turn, climate
change may exacerbate those effects, further diminishing habitat and
increasing the isolation of already declining populations, making them
more susceptible to genetic deterioration, disease, or catastrophic
events such as drought and fire. Drought, a substantial threat to
Gunnison sage-grouse rangewide, likely intensifies other threats such
as predation, invasive plants, habitat loss, and fire. The impact of
residential development is increased by the additional disturbance
footprint and area of species' avoidance of other infrastructure such
as roads, powerlines, and fences. Further, predation on Gunnison sage-
grouse may increase as a result of the increase in human disturbance
and development. The impact of residential development can be increased
by other anthropogenic stressors resulting in habitat loss and decline,
such as powerlines, roads, and other infrastructure. Numerous threats
are likely acting cumulatively to further increase the likelihood that
the species will become extinct in the future. The cumulative effects
of ongoing and future threats (Factors A through E), and small and
declining population size and structure, in particular, are likely to
further reduce resiliency, redundancy, and representation of the
species.
Determination
We have carefully assessed the best scientific and commercial
information available regarding the past, present, and future threats
to the Gunnison sage-grouse. We consider the five factors identified in
section 4(a)(1) of the Act in determining whether the Gunnison sage-
grouse meets the Act's definition of an endangered species (section
3(6)) or a threatened species (section 3(20)).
Section 3 of the Act defines an ``endangered species'' as ``any
species which is in danger of extinction throughout all or a
significant portion of its range,'' and defines a ``threatened
species'' as ``any species which is likely to become an endangered
species within the foreseeable future throughout all or a significant
portion of its range.'' Although these statutory definitions are
similar, there is a crucial temporal distinction between them. The
statutory definition of an ``endangered species,'' a species that ``is
in danger of extinction,'' connotes an established, present condition.
The statutory definition of a ``threatened species,'' a species that is
``likely to become an endangered species within the foreseeable
future,'' connotes a predicted or expected future condition. Thus, a
key statutory difference between a threatened and endangered species is
the time of when a species may be in danger of extinction, either now
(endangered) or in the foreseeable future (threatened).
As a result of new information and comments received on the
proposed rule, we have reconsidered our prior determination that the
Gunnison sage-grouse is currently in danger of extinction and therefore
meets the definition of an ``endangered species'' under the Act. This
reconsideration focuses on the principal threat relied upon in the
proposed rule, the threat to the species posed by current residential
development and associated infrastructure, especially in the critical
Gunnison Basin population area.
In the proposed rule, we reported that the results of a GIS
analysis of parcel ownership and development in occupied habitat in
Gunnison County indicated that the current level of residential
development in this habitat was strongly decreasing the likelihood of
Gunnison sage-grouse using 49 percent of this land area as nesting
habitat. This analysis was based on a model indicating Gunnison sage-
grouse tend to select nest sites in larger landscapes (1.5 km [0.9 mi]
radii) with a low density of residential development (Aldridge 2012, p.
10). We considered the results of applying this modeling to the current
level of residential development to be particularly concerning given
the close link of nesting habitat to early brood rearing habitat and
the sensitivity of the species population dynamics during these life
history stages. In assessing the
[[Page 69303]]
risk posed by current levels of residential development, we also noted
that the GSRSC (2005, pp. 160-61) hypothesized that residential density
in excess of one housing unit per 1.3 km\2\ (0.5 mi\2\) could cause
declines in Gunnison sage-grouse populations, and that under this
hypothesis residential development is limiting the species in
approximately 18 percent of its habitat in Gunnison County.
Since our proposed listing rule, we reevaluated residential
development and found it to be a current threat to the species as a
whole, but that it is a lower magnitude threat to the Gunnison Basin
population than we previously thought. Our reevaluation of residential
development in the Gunnison Basin (Factor A above) found that human
developments in occupied Gunnison sage-grouse habitat in Gunnison
County occur and have increased over time. Our overall conclusion,
however, was that current development in the Gunnison Basin population
area is a threat of low magnitude to the persistence of this Gunnison
sage-grouse population. The Gunnison Basin population is currently
relatively stable, based on population trends since 1996. It is also
the most important population for the species' survival with
approximately 63 percent of occupied habitat, approximately 60 percent
of the leks, and 84 percent of the rangewide population occurring in
Gunnison Basin. Thus the current level of threat of residential
development in the Gunnison Basin is not causing the rangewide
population to trend towards extinction.
Based on the factors presented in the Residential Development
Section above (Factor A), outside of the Gunnison Basin, residential
development is likely to have the greatest impact on the San Miguel,
Cerro Summit-Cimarron-Sims Mesa, and Poncha Pass populations of
Gunnison sage-grouse. For the remaining three Gunnison sage-grouse
populations, we found that current residential development may impact
individual birds or areas of habitat, but is a threat of low magnitude
at the population level at the present time. Although residential
development is a current and future threat to the San Miguel, Cerro
Summit-Cimarron-Sims Mesa, and Poncha Pass populations, we do not
believe that it is a significant threat to the species rangewide such
that it meets the definition of an endangered species.
We find that the other factors that we identified as threats in the
proposed rule (inadequate regulatory mechanisms, genetic issues and
small population sizes, predation, improper grazing management, and the
interaction among climate change, invasive plants and drought/weather)
are still current threats to the species, but when considered
individually and cumulatively with other current threats (including the
lower level of the threat of development to the Gunnison Basin
population), they do not support a finding that the species is
currently in danger of extinction. Based on the preceding analysis, we
have determined that Gunnison sage-grouse is not an endangered species
as defined in the Act.
However, considering both our analysis of the species' status here
and in the proposed listing rule, and new information and comments
received following publication of the proposed rule, we find that
Gunnison sage-grouse qualifies as a threatened species under the Act
because it is likely to become in danger of extinction throughout all
of its range in the foreseeable future.
The Act does not define the term ``foreseeable future.'' In a
general sense, the foreseeable future is the period of time over which
events can reasonably be anticipated. In the context of the definition
of ``threatened species,'' the Service interprets the foreseeable
future as the extent of time over which the Secretary can reasonably
rely on predictions about the future in making determinations about the
future conservation status of the species. It is important to note that
references to ``reliable predictions'' are not meant to refer to
reliability in a statistical sense of confidence or significance;
rather the words ``rely'' and ``reliable'' are intended to be used
according to their common, non-technical meanings in ordinary usage. In
other words, we consider a prediction to be reliable if it is
reasonable to depend upon it in making decisions, and if that
prediction does not extend past the support of scientific data or
reason so as to venture into the realm of speculation.
In considering threats to the species and whether they rise to the
level such that listing the species as a threatened or endangered
species is warranted, we assess factors such as the imminence of the
threat (is it currently affecting the species or, if not, when do we
expect the effect from the threat to commence, and whether it is
reasonable to expect the threat to continue into the future), the scope
or extent of the threat, the severity of the threat, and the
synergistic effects of all threats combined. If we determine that the
species is not currently in danger of extinction, then we must
determine whether, based upon the nature of the threats, it is
reasonable to anticipate that the species may become in danger of
extinction within the foreseeable future. As noted in the 2009
Department of the Interior Solicitor's opinion on foreseeable future,
``in some cases, quantifying the foreseeable future in terms of years
may add rigor and transparency to the Secretary's analysis if such
information is available. Such definitive quantification, however, is
rarely possible and not required for a foreseeable future analysis''
(M-37021, January 16, 2009; p. 9). In some specific cases where
extensive data are available to allow for the modeling of extinction
probability over various time periods (e.g., the PVAs performed on the
Gunnison sage-grouse), the Service has provided quantitative estimates
of what may be considered to constitute the foreseeable future.
We consider foreseeable future in this final rule to be 40-60 years
based on the following:
(1) The most current and comprehensive demographic study and
population viability analysis (Davis 2012). In contrast to the RCP PVA
described below, this study exclusively used demographic information
from Gunnison sage-grouse and included environmental stochastic factors
such as fire, disease, and drought. This analysis was done for the
Gunnison Basin (2005-2010) and the San Miguel populations (2007-2010),
the two largest populations (Davis 2012, entire). The study concluded
that the small San Miguel Basin population had a high probability (53
percent chance) of going extinct in the next 30 years. For the Gunnison
Basin population, the model found a minimum extinction time of 31 years
and a mean extinction time of 58 years, based on a six-year data set
during a period with a slightly declining population. However, because
the study occurred during a drought period and the overall population
declined during this period, which is inconsistent with the long-term
record of stability for this population, we are also utilizing the RCP
PVA in our consideration of the foreseeable future.
(2) A second population viability analysis done in conjunction with
the RCP. This PVA found that small populations of birds (< 25 and 25 to
50 birds) are at a high risk of extinction within the next 50 years
(2055) with an 86 percent and 59 percent chance of extinction
respectively (GSRSC 2005, pp. 170 and G-27). For the Gunnison Basin
population, this PVA found the probability of extinction in the next 50
years was less than 1 percent (GSRSC 2005, p. G-21).
(3) The Gunnison Basin Climate Change Vulnerability Assessment (The
Nature Conservancy (TNC) et al. 2011,
[[Page 69304]]
p. 4), which uses a timeframe of 50 years to project the likely effects
of climate change in the Gunnison Basin.
As noted in the proposed listing rule, we anticipate that current
threats to the species will increase over time throughout the species'
range. Based on the analysis of the listing Factors A-E described
above, we now find that the Gunnison sage-grouse is ``likely to become
endangered throughout all or a significant portion of its range within
the foreseeable future'' based on the following continuing, new, and
increasing threats, which are acting on the species individually and
cumulatively, contributing to the challenges faced by Gunnison sage-
grouse in the foreseeable future:
(1) Small population size and population structure (Factor E) occur
in all of the six satellite populations, or across approximately 37
percent of occupied range for the species. Without concerted management
effort, one or more of the satellite populations are likely to go
extinct in the next 50 years. Satellite populations are isolated and
small, with generally declining trends, low resilience, and low genetic
diversity. The small sizes of the satellite populations of Gunnison
sage-grouse make them particularly sensitive to stochastic and
demographic fluctuations, and this vulnerability is exacerbated by
other threats such as drought. Having multiple populations across a
broad geographic area (population redundancy) is needed to provide
insurance against such catastrophic events.
(2) Gunnison sage-grouse require large areas of sagebrush for long-
term persistence, and thus are affected by factors that occur at the
landscape scale. Habitat decline, including habitat loss, degradation,
and fragmentation of sagebrush habitats (Factor A), is a primary cause
of the decline of Gunnison sage-grouse populations. Habitat loss due to
residential and infrastructural development (including roads,
powerlines, and fences) is a significant threat to Gunnison sage-grouse
across its range. Due to habitat decline, the seven individual
populations are now mostly isolated, with limited migration and gene
flow among populations, increasing the likelihood of population
extirpations.
a. Thirty-two percent of occupied Gunnison sage-grouse habitat
rangewide is at risk of residential development (Factor A). Residential
development is a substantial risk to the San Miguel, Poncha Pass, and
Cerro-Cimarron-Sims populations, and the effects of residential
development will likely reduce connectivity among satellite populations
and potential connectivity between the Gunnison Basin and satellite
populations to the west. Although our reevaluation found the threat of
current residential development in the Gunnison Basin to be of a lower
magnitude than previously thought, we believe that the level of impact
and threat from residential development will increase in the Gunnison
Basin population in the future.
The collective influences of fragmentation and disturbance from
roads (Factor A) reduce the amount of effective habitat, as roads are
largely avoided by sage-grouse. Powerlines and fences (Factor A) also
fragment habitat and are avoided by sage-grouse. They are also sources
of direct mortality through strikes, electrocution, and by attracting
and increasing the predator population.
(3) Drought (Factor E) has contributed to substantial declines in
all Gunnison sage-grouse populations. Drought likely intensifies other
stressors such as predation, invasive plants, and fire. Based on the
best available information, we concluded that drought is a substantial
threat to Gunnison sage-grouse rangewide, both now and into the future.
(4) Warming is occurring more rapidly in the southwestern region of
the United States, including western Colorado, than elsewhere in the
country. Based on the best available information on climate change
projections over the next 35 years or so, climate change (Factor A) has
the potential to alter important seasonal habitats and food resources
of Gunnison sage-grouse, the distribution and extent of sagebrush, and
the occurrence of invasive weeds and associated fire frequencies.
Climate change effects, including increased drought, are predicted in
all populations.
(5) West Nile virus (Factor C) is present throughout most of the
range of Gunnison sage-grouse. Although the disease has not yet been
documented in any Gunnison sage-grouse, it has caused large mortality
events and has also caused the deaths of other gallinaceous birds
including greater sage-grouse. The effects of drought and increased
temperatures will contribute to the prevalence and spread of West Nile
virus and, therefore, the exposure of Gunnison sage-grouse to this
disease. We concluded that West Nile virus is a future threat to
Gunnison sage-grouse rangewide.
(6) The Davis PVA (2012) is the most current and comprehensive
demographic study and population viability analysis. This study
exclusively used demographic information from Gunnison sage-grouse and
incorporated environmental stochasticity (variability in population
growth rates due to external factors such as weather, fire, disease,
and predation) and demographic stochasticity (variability in population
growth rates due to survival and reproduction rates). Model simulations
predicted population declines in the future (Davis 2012, pp. 105-106).
Combining the six years of demographic data (2005 to 2010) from both
populations, environmental stochastic simulations resulted in a minimum
extinction time of 31 years and a mean or expected extinction time in
this PVA of 58 years. Although this model shows that the extinction
probability for the Gunnison Basin population is farther into the
future, it still supports a determination that the species is likely to
become endangered in the foreseeable future.
(7) We have found the above-listed factors to be significant
threats that are acting on Gunnison sage-grouse populations rangewide
and collectively are likely to increase over time. We further examined
whether these threats to the Gunnison sage-grouse are adequately
addressed by existing regulatory mechanisms (Factor D). We evaluated
the adequacy of existing local, State, and Federal plans, laws, and
regulations currently in place across the range of the species and
determined that while they will help to reduce the negative effects of
human development and infrastructure on Gunnison sage-grouse in some
respects, and that continuation of these efforts across the species'
range will be necessary for conservation of the species, cumulatively
the existing regulatory mechanisms are not being appropriately
implemented such that land-use practices result in habitat conditions
that adequately support the life-history needs of the species. Existing
plans, laws, and regulations are not effective at ameliorating the
threats resulting from small population size and structure, habitat
decline, drought, climate change, and disease as discussed above.
Further, while these regulatory mechanisms may help reduce current
threats to the species, they are insufficient to fully reduce or
eliminate the increase in threats that may act on the species in the
future.
(8) Other current and future threats to the species identified in
this final rule, including grazing management inconsistent with local
ecological conditions, fences, invasive plants, fire, mineral
development, pi[ntilde]on-juniper encroachment, large scale water
development (all in Factor A); predation
[[Page 69305]]
(primarily associated with anthropogenic disturbance and habitat
decline)(Factor C); and recreation (Factor E) are acting at a more
localized level, and while individually may affect some populations
more than others, they do not individually or cumulatively rise to the
level of a significant rangewide threat. However, the current impacts
of these threats do contribute to the overall status of the species as
``likely to become endangered in the foreseeable future''. As discussed
under the Threat Factors sections above, we also expect that many of
these threats will increase in the future.
Summary of the Threatened Determination
In summary, multiple threats affecting Gunnison sage-grouse and its
habitat are occurring and interacting synergistically, resulting in
increasingly fragmented habitat and other threats. We expect all of
these threats to increase in the future. The components of human
infrastructure, once present on the landscape, become virtually
permanent features, fragmenting sagebrush habitats, and resulting in
the reduction or elimination of proactive and effective management
alternatives. We anticipate other threats such as drought, climate
change, invasive species, and fire frequency to increase in the future
and to act synergistically to become greater threats to Gunnison sage-
grouse. We anticipate renewable energy development, particularly
geothermal and wind energy development, to increase in some population
areas. Taken cumulatively, the ongoing and future habitat-based impacts
in all populations will likely act to fragment and further isolate
populations of the Gunnison sage-grouse. As these threats increase, one
or more of the satellite populations are likely to go extinct due to
small population size, genetic factors, and stochastic environmental
events and the remaining populations will become in danger of
extinction.
Therefore, we find that Gunnison sage-grouse is likely to become
endangered throughout all of its range in the foreseeable future, and
thus is a threatened species as defined by the Act.
As noted above, in determining that Gunnison sage-grouse is a
threatened species, we also considered ongoing conservation efforts and
existing regulatory mechanisms. Based on the best available information
(Factor A and Factor D), such conservation efforts are not currently
adequate to address the full scope of threats to Gunnison sage-grouse,
particularly habitat loss and decline, small population size and
structure, drought, climate change, and disease. While some efforts
have provided conservation benefits at the rangewide scale, such as the
CCAA and CEs, these and other conservation efforts are limited in scope
and therefore limited in their ability to effectively reduce or remove
the threats to the species and its habitat across its range. Thus,
although ongoing conservation efforts are a positive step toward
conserving Gunnison sage-grouse, and some have undoubtedly reduced the
severity of certain threats to the species, on the whole we find that
current conservation efforts are not sufficient to offset the full
scope of threats to Gunnison sage-grouse or prevent the increase in
threats that result in the species likely becoming in danger of
extinction in the foreseeable future. Therefore, we cannot conclude
that the species is not warranted for listing.
Therefore, on the basis of the best available scientific and
commercial information, we are listing Gunnison sage-grouse as
threatened in accordance with sections 3(20) and 4(a)(1) of the Act.
The Gunnison sage grouse is restricted in its range and the threats
occur throughout its range. Therefore, we assessed the status of the
species throughout its entire range. Under the Act and our implementing
regulations, a species may warrant listing if it is endangered or
threatened throughout all or a significant portion of its range.
Because we have determined that Gunnison sage-grouse is threatened
throughout all of its range, no portion of its range can be
``significant'' for purposes of the definitions of ``endangered
species'' and ``threatened species.'' See the Final Policy on
Interpretation of the Phrase ``Significant Portion of Its Range'' in
the Endangered Species Act's Definitions of ``Endangered Species'' and
``Threatened Species'' (79 FR 37577).
Available Conservation Measures
Conservation measures provided to species listed as endangered or
threatened under the Act include recognition, recovery actions,
requirements for Federal protection, and prohibitions against certain
practices. Recognition through listing results in public awareness and
conservation by Federal, State, Tribal, and local agencies, private
organizations, and individuals. The Act encourages cooperation with the
States and requires that recovery actions be carried out for all listed
species. The protection required by Federal agencies and the
prohibitions against certain activities are discussed, in part, below.
The primary purpose of the Act is the conservation of endangered
and threatened species and the ecosystems upon which they depend. The
ultimate goal of such conservation efforts is the recovery of these
listed species, so that they no longer need the protective measures of
the Act. Subsection 4(f) of the Act requires the Service to develop and
implement recovery plans for the conservation of endangered and
threatened species. The recovery planning process involves the
identification of actions that are necessary to halt or reverse the
species' decline by addressing the threats to its survival and
recovery. The goal of this process is to restore listed species to a
point where they are secure, self-sustaining, and functioning
components of their ecosystems.
Recovery planning includes the development of a recovery outline
shortly after a species is listed, and preparation of a draft and final
recovery plan. The recovery outline guides the immediate implementation
of urgent recovery actions and describes the process to be used to
develop a recovery plan. The recovery plan identifies site-specific
management actions that set a trigger for a review of the five factors
that control whether a species remains endangered or threatened or may
be downlisted or delisted, and methods for monitoring recovery
progress. Revisions of the plan may be made to address continuing or
new threats to the species, as new substantive information becomes
available. Incorporating or adapting components of the Gunnison sage-
grouse RCP for a recovery outline will be considered. Recovery plans
also establish a framework for agencies to coordinate their recovery
efforts and provide estimates of the cost of implementing recovery
tasks. Recovery teams (composed of species experts, Federal and State
agencies, nongovernmental organizations, and stakeholders) are often
established to develop recovery plans. When completed, the recovery
outline, draft recovery plan, and the final recovery plan will be
available on our Web site (http://www.fws.gov/endangered), or from our
Western Colorado Field Office (see FOR FURTHER INFORMATION CONTACT).
Implementation of recovery actions generally requires the
participation of a broad range of partners, including other Federal
agencies, States, Tribes, nongovernmental organizations, businesses,
and private landowners. Examples of recovery actions include habitat
restoration (e.g., restoration of native vegetation), research, captive
propagation and reintroduction, and outreach and education. The
recovery of
[[Page 69306]]
many listed species cannot be accomplished solely on Federal lands
because their range may occur primarily or solely on non-Federal lands.
To achieve recovery of these species requires cooperative conservation
efforts on private, State, and Tribal lands.
Funding for recovery actions may be available from a variety of
sources, including Federal budgets, State programs, and cost share
grants for non-Federal landowners, the academic community, and
nongovernmental organizations. In addition, pursuant to section 6 of
the Act, the States of Colorado and Utah will be eligible for Federal
funds to implement management actions that promote the protection and
recovery of the Gunnison sage-grouse. Information on our grant programs
that are available to aid species recovery can be found at: http://www.fws.gov/grants.
Please let us know if you are interested in participating in
recovery efforts for this species. Additionally, we invite you to
submit any new information on this species whenever it becomes
available and any information you may have for recovery planning
purposes (see FOR FURTHER INFORMATION CONTACT).
Section 7(a) of the Act requires Federal agencies to evaluate their
actions with respect to any species that is proposed or listed as
endangered or threatened and with respect to its critical habitat, if
any is designated. Regulations implementing this interagency
cooperation provision of the Act are codified at 50 CFR part 402. When
a species is listed, section 7(a)(2) of the Act requires Federal
agencies to ensure that activities they authorize, fund, or carry out
are not likely to jeopardize the continued existence of the species or
destroy or adversely modify its critical habitat. If a Federal action
may affect a listed species or its critical habitat, the responsible
Federal agency must enter into consultation with the Service.
Federal agency actions within the species' habitat that may require
consultation as described in the preceding paragraph include management
and any other landscape-altering activities on Federal lands
administered by the Bureau of Land Management, U.S. Forest Service, and
National Park Service; issuance of section 404 Clean Water Act permits
by the Army Corps of Engineers; construction and management of gas
pipeline and power line rights-of-way by the Federal Energy Regulatory
Commission; and construction and maintenance of roads or highways by
the Federal Highway Administration.
The Act and its implementing regulations set forth a series of
general prohibitions and exceptions that apply to all endangered and
threatened wildlife. The prohibitions of section 9(a)(2) of the Act,
codified at 50 CFR 17.21 for endangered wildlife, in part, make it
illegal for any person subject to the jurisdiction of the United States
to take (includes harass, harm, pursue, hunt, shoot, wound, kill, trap,
capture, or collect; or to attempt any of these), import, export, ship
in interstate commerce in the course of commercial activity, or sell or
offer for sale in interstate or foreign commerce any listed species.
Under the Lacey Act (18 U.S.C. 42-43; 16 U.S.C. 3371-3378), it is also
illegal to possess, sell, deliver, carry, transport, or ship any such
wildlife that has been taken illegally. Certain exceptions apply to
agents of the Service and State conservation agencies.
We may issue permits to carry out otherwise prohibited activities
involving endangered and threatened wildlife species under certain
circumstances. Regulations governing permits are codified at 50 CFR
17.22 for endangered species, and at 17.32 for threatened species. With
regard to endangered wildlife, a permit must be issued for the
following purposes: for scientific purposes, to enhance the propagation
or survival of the species, and for incidental take in connection with
otherwise lawful activities.
It is our policy, as published in the Federal Register on July 1,
1994 (59 FR 34272), to identify to the maximum extent practicable at
the time a species is listed, those activities that would or would not
constitute a violation of section 9 of the Act. The intent of this
policy is to increase public awareness of the effect of a listing on
proposed and ongoing activities within the range of listed species. The
following activities could potentially result in a violation of section
9 of the Act; this list is not comprehensive:
(1) Unauthorized collecting, handling, possessing, selling,
delivering, carrying, or transporting of the species, including import
or export across State lines and international boundaries, except for
properly documented antique specimens of these taxa at least 100 years
old, as defined by section 10(h)(1) of the Act.
(2) Actions that would result in the loss of sagebrush overstory
plant cover or height. Such activities could include, but are not
limited to, the removal of native shrub vegetation by any means for any
infrastructure construction project; direct conversion of sagebrush
habitat to agricultural land use; habitat improvement or restoration
projects involving mowing, brush-beating, Dixie harrowing, disking,
plowing, Tebuthiuron (Spike) and other herbicide applications, or
prescribed burning; and fire suppression activities.
(3) Actions that would result in the loss or reduction in native
herbaceous understory plant cover or height, and a reduction or loss of
associated arthropod communities. Such activities could include, but
are not limited to, livestock grazing, the application of herbicides or
insecticides, prescribed burning and fire suppression activities; and
seeding of nonnative plant species that would compete with native
species for water, nutrients, and space.
(4) Actions that would result in Gunnison sage-grouse avoidance of
an area during one or more seasonal periods. Such activities could
include, but are not limited to, the construction of vertical
structures such as power lines, fences, communication towers,
buildings; motorized and non-motorized recreational use; and activities
such as well drilling, operation, and maintenance, which would entail
significant human presence, noise, and infrastructure.
Questions regarding whether specific activities would constitute a
violation of section 9 of the Act should be directed to the Western
Colorado Field Office (see FOR FURTHER INFORMATION CONTACT). Requests
for copies of the regulations concerning listed animals and general
inquiries regarding prohibitions and permits may be addressed to the
U.S. Fish and Wildlife Service, Endangered Species Permits, Denver
Federal Center, P.O. Box 25486, Denver, Colorado, 80225-0489 (telephone
(303) 236-4256; facsimile (303) 236-0027).
Under section 4(d) of the ESA, the Secretary has discretion to
issue such regulations as he deems necessary and advisable to provide
for the conservation of threatened species. Our implementing
regulations (50 CFR 17.31) for threatened wildlife generally
incorporate the prohibitions of section 9 of the Act for endangered
wildlife, except when a ``special rule'' promulgated pursuant to
section 4(d) of the Act has been issued with respect to a particular
threatened species. In such a case, the general prohibitions in 50 CFR
17.31 would not apply to that species, and instead, the special rule
would define the specific take prohibitions and exceptions that would
apply for that particular threatened species, which we consider
necessary and advisable to conserve the species. The Secretary also has
the discretion to prohibit by regulation with respect to a
[[Page 69307]]
threatened species any act prohibited by section 9(a)(1) of the ESA.
Exercising this discretion, which has been delegated to the Service by
the Secretary, the Service has developed general prohibitions that are
appropriate for most threatened species in 50 CFR 17.31 and exceptions
to those prohibitions in 50 CFR 17.32. We continue to evaluate the
appropriateness of issuing a special rule for the Gunnison sage-grouse
in the future.
Conservation Measures for Gunnison Sage-Grouse Recovery
We want to work cooperatively with and to support the ongoing
conservation efforts of the many public and private partners across the
range. Our desire is to build on the important existing conservation
efforts of many partners to bring the species to a point where listing
will no longer be necessary.
In 2005, the Gunnison sage-grouse Range-wide Conservation Plan
(RCP) (Gunnison Sage-grouse Rangewide Steering Committee 2005)
identified conservation actions for the Gunnison sage-grouse. In 2013,
the counties belonging to the County Coalition for Gunnison sage-grouse
indicated that they would work with Colorado Parks & Wildlife (CPW) to
update and revise the RCP in the near future to better reflect best
available science and conservation progress made to date. Our partners,
the counties, and the public asked the Service for our perspective on
what conservation actions would be necessary to conserve the Gunnison
sage-grouse. In advance of the revision of the RCP, and in advance of
recovery planning for the species, the Service gathered the best
available information and conferred with our partners to outline
conservation recommendations that, if achieved, would improve the
Service's confidence in the conservation of Gunnison sage-grouse. The
conservation recommendations identified here are intended to update,
modify, and build on the conservation strategies in the 2005 RCP and to
be discussed in the context of an upcoming revision to the RCP. The
approach and actions identified in this section, if completed, would
help increase the satellite populations' redundancy to the Gunnison
Basin population, thereby increasing the resiliency of the species. The
Service further recommends that a recovery strategy include population
and habitat targets for the Gunnison Basin and the satellite
populations using a scientifically defensible, peer-reviewed approach.
Targeting Satellite Populations for Conservation Efforts
The Gunnison Basin is the largest population (approximately 3,978
birds in 2014) and, while showing variation from 1996 to 2014, has been
relatively stable. However, redundancy to the Gunnison Basin population
is a necessary element to have confidence in the conservation of the
Gunnison sage-grouse. Confidence in redundancy provided by a satellite
population is based on whether the satellite population is able to
withstand perturbations and recover and persist. We recommend
developing a recovery strategy that will be built around the resilience
of multiple satellite populations to provide redundancy to the Gunnison
Basin population.
The total abundance of Gunnison sage-grouse is an important
indicator of species-level resiliency. Of the six satellite
populations, Poncha Pass and Cerro Summit-Cimarron-Sims Mesa have very
low population numbers to the extent that their potential to provide
redundancy would be very limited without extraordinary conservation
actions taking place over a long period of time. Therefore, to maximize
the potential to achieve resilience in the satellite populations that
would provide redundancy to the Gunnison Basin population, our initial
recommendations for conservation measures focus on the Pi[ntilde]on
Mesa, Crawford, San Miguel, and Dove Creek-Monticello satellite
populations. In addition, the Service agrees with the RCP assertion
that the Cerro Summit-Cimarron-Sims Mesa area is needed for the
conservation of Gunnison sage-grouse, as it has and should continue to
provide an important habitat linkage to the other satellite
populations. However, the Service recommends focusing limited
conservation resources on the four larger satellite populations while
still protecting the Cerro Summit-Cimarron-Sims Mesa area. This
approach should yield the quickest conservation results and improve the
resilience of the species as a whole.
Summary of Service Recommendations
As soon as possible, we want to work with CPW and UDWR to convene
science experts to identify targets for population numbers, habitat
acreage, sagebrush cover, and limiting factors for the above-identified
satellite populations. Development of the targets will guide recovery
efforts and improve confidence in the conservation of the species as
they are achieved.
Overarching Conservation Objectives
We recommend protections that should apply rangewide and could be
achieved on Federal and non-Federal lands.
Protection of Gunnison Sage-Grouse Habitat That Is Currently Occupied,
or That Becomes Occupied Through Future Expansion
Any further loss of habitat quality or quantity of habitat will
decrease the long-term viability of Gunnison sage-grouse. In addition,
current occupied habitat is not of sufficient quality or quantity to
provide confidence in conservation of the Gunnison sage-grouse.
Therefore the goal should be to protect all habitat that is occupied or
that becomes occupied through future expansion from future loss and/or
degradation, including temporary degradation related to indirect
impacts of surface occupancy and/or disruptive activities.
A 4-mile restriction on surface disturbance (e.g. No Surface
Occupancy) for all surface-disturbing activities around a lek should be
enforced. If there are circumstances that preclude No Surface Occupancy
within 4 miles around a lek, such as existing disturbances, disruptive
activities, or valid existing fluid or locatable mineral rights in
occupied habitat, permitted activities should follow the mitigation
hierarchy of avoiding impact to the degree possible, minimizing impact,
and providing compensatory mitigation to offset any unavoidable
impacts. In addition, for those areas where No Surface Occupancy is
precluded, the following recommendations apply:
Limit permitted surface disturbances to 1 per section with
no more than 3 percent surface disturbance, factoring in existing and
new impacts, in that section.
Protect breeding habitat and leks from future loss and/or
degradation, including temporary degradation related to indirect
impacts of surface occupancy and/or disruptive activities.
Leks and the area within 0.6 miles must be avoided and
protected from surface occupancy and disruptive activities.
[cir] If avoidance and/or disturbance is not possible due to pre-
existing valid rights, adjacent development, or split estate issues,
development and/or disruptive activities should only be allowed in non-
habitat areas with an adequate buffer to preclude impacts to sage-
grouse habitat from noise and other human activities.
Protect nesting habitat from any future loss and/or degradation,
[[Page 69308]]
including temporary degradation related to indirect impacts of surface
occupancy and/or disruptive activities.
The area from 1 to 6.5 km (0.6 to 4.0 mi) around a lek
must be protected between March 1st and July 15th. Outside of this
period, some disturbance may occur, but only if the disturbance does
not exceed the disturbance cap, all feasible measures are taken to
minimize impacts, and it is determined that the cumulative impact does
not negatively affect reproductive success or reduce an individual's
physiological ability to cope with environmental stress, and will not
in the future.
Protect winter habitat from any future loss and/or degradation,
including temporary degradation related to indirect impacts of surface
occupancy and/or disruptive activities.
Winter habitats need to be identified by CPW or UDWR and
protected from October 1st to March 1st. If winter habitat and winter
refuge areas are not identified, all potential winter habitat must be
protected from October 1st to March 1st. Outside of this period, some
disturbance may occur, but only if the disturbance does not exceed the
disturbance cap, all feasible measures are taken to minimize impacts,
and if it is determined that the cumulative impact does not remove or
negatively impact the stands of sage-brush necessary for Gunnison sage-
grouse winter survival.
Maintain summer brood-rearing habitat. In grazed areas, require
grazing management appropriate to local ecological conditions to
promote and achieve habitat characteristics representative of healthy
sagebrush ecosystems and sage-grouse habitat.
Areas within 0.4 km (0.25 mi) of known late summer/brood-
rearing habitat must be maintained or enhanced to represent habitat
characteristics representative of brood-rearing habitats described in
the RCP.
Prevent noise disturbance during the breeding season.
Do not allow any disruptive activities or surface
occupancy that will increase noise levels 10 dBa above ambient noise
level measured at sunrise at the perimeter of leks during the breeding
season (March 1st to May 31st).
Increase Occupied Habitat
Reclaim and restore degraded habitat to meet characteristics of
functional, seasonal sage-grouse habitats.
Existing disturbances should meet reclamation standards
that are aimed at restoring disturbances to functional sage-grouse
habitat as described in the RCP and are representative of the pre-
disturbance habitat type.
Range-Wide Mitigation Strategy
In the Gunnison Basin and the satellite populations, any
development and/or disruptive activities in occupied habitat will
impact Gunnison sage-grouse. We recommend the development of land-use
regulations that prescribe the following mitigation hierarchy of avoid,
minimize, and compensate for unavoidable impacts, at the State or local
level.
If avoidance of surface disturbance and disruptive activities
around leks cannot be achieved, efforts to minimize and compensate for
impacts will not offset impacts. Avoidance of direct and/or indirect
disturbance of the area within 0.6 miles of existing leks is critical,
due to sage-grouse site fidelity (Connelly 2000).
If land use regulations quantify the negative impacts of surface
disturbance and disruptive activities on Gunnison sage-grouse and then
require an offset that provides a net conservation benefit, that would
help ensure that negative impacts do not overshadow conservation
efforts. To be effective, mitigation policy must require avoidance of
impacts as the highest priority, then minimization of impacts and
finally offset of unavoidable impacts through conservation actions.
The San Miguel and Dove Creek-Monticello satellite populations may
be impacted by oil and gas development. To manage the potential impact
of oil and gas development, mitigation policy should specify best
management practices and conservation measures to minimize impacts of
oil and gas development to Gunnison sage-grouse and their habitat.
Conservation Actions Recommended for San Miguel, Dove Creek-Monticello,
Crawford, and Pi[ntilde]on Mesa Satellite Populations
The following are near-term high-priority recommendations for four
of the satellite populations.
Assess Existing Habitat Availability and Quality
Habitat loss and degradation are recognized as causes of the
decline in abundance and distribution of Gunnison sage-grouse. The
Service agrees with the 2005 RCP recommendation that Gunnison sage-
grouse seasonal habitat should be identified, habitat quality assessed,
and changes in habitat monitored over time. If CPW and UDWR identify
seasonal habitat types and assess habitat quality, it will improve
their ability to identify potential limiting habitat types and
prioritize habitat restoration efforts. The Gunnison Basin Sage-Grouse
Habitat Prioritization Tool (HPT) identifies sage-grouse habitat and
then discounts the value of the habitat based on distance to
structures, roads, and power lines. However, the HPT covers only the
Gunnison Basin and does not possess the functionality to determine
habitat quality. A tool should be developed for all of the populations
to monitor and detect changes to habitat quality and seasonal habitat
availability. A habitat mapping tool could help identify where and how
to improve habitat quality, prioritize habitat improvement projects,
evaluate development threats and protection needs, and adaptively
manage Gunnison sage-grouse for the satellite populations.
Reduce Pinyon-Juniper Encroachment
Pinyon-juniper encroachment degrades and, if untreated, eliminates
sage-grouse habitat. Treatment of phase I and phase II encroachment
levels of pinyon-juniper adjacent to occupied habitat is often the
quickest and least expensive method to restore sagebrush habitat for
sage-grouse. Under the Natural Resource Conservation Service (NRCS)
Sage-Grouse Initiative (SGI), a geo-spatial analysis of potential
pinyon-juniper removal is being completed for each of the Western
Association of Fish & Wildlife Association (WAFWA) sage-grouse
Management Zones (MZ). The range of the Gunnison sage-grouse is in MZ
VII. Once the analysis is completed for MZ VII, phase I and II
encroaching pinyon-juniper should be removed, starting within 6.5 km (4
mi) of occupied habitat and expanding out by 6.5 km (4 mi) as restored
habitat is occupied until habitat targets are achieved for each
satellite population.
Road Closures
Disturbance from roads and vehicular traffic near leks during the
breeding season must be reduced and/or minimized. Road closures,
seasonal timing restrictions, and proper siting of new roads should be
used to eliminate or minimize disturbance. In the Pi[ntilde]on Mesa
population, a seasonal closure and time of day restrictions for the
section of MS County Road that is directly adjacent to one of the leks
will remove a significant source of potential disturbance to that
population.
Grazing Management Appropriate to Ecological Conditions
Overgrazing that is not appropriate for ecological conditions on
the range can lead to habitat degradation. Continued enrollment of
ranchers into the NRCS
[[Page 69309]]
SGI will improve grazing management. Landowners and land managers who
manage cattle on both private and public lands should be encouraged to
manage across ownerships for sage-grouse conservation. The Service will
consider lands already enrolled in the Candidate Conservation Agreement
with Assurances, implementation of NRCS practices on private rangelands
that follow Conference Opinion guidance, and lands subject to other
programs that require signed commitments to manage grazing appropriate
to ecological conditions when assessing the acreage being grazed in a
manner appropriate to ecological conditions in a satellite population.
Prioritize Translocations
The small population size and structure of the six satellite
populations of Gunnison sage-grouse raises concerns about the
probability of extirpation of the satellite populations and extinction
of the species due to demographic and/or environmental stochasticity.
Colorado Parks & Wildlife has indicated that recent translocations have
had a positive influence on the population counts seen in 2012-2013. In
order to maximize the population augmentation benefits of
translocation, the Colorado Parks & Wildlife Trap and Transplant
Committee should revise the translocation strategy to allow for
prioritization of the Pi[ntilde]on Mesa, Crawford, San Miguel, and Dove
Creek-Monticello satellite populations. The revision should address how
timing (spring and/or fall), age class (adult or yearling), gender, and
quantity of transplants can increase the resilience of the Pi[ntilde]on
Mesa, Crawford, San Miguel, and Dove Creek-Monticello satellite
populations. CPW should also continue to evaluate the effectiveness of
translocation strategies to maximize their effectiveness.
Protection of Targeted Occupied Habitat
The Service agrees with the RCP recommendation that 90 percent of
habitats currently occupied, or that become occupied through future
expansion should be protected through a combination of voluntary
agreements, land use planning, conservation easements, fee-title
acquisition, or land trades. We would consider a variety of
conservation efforts as providing protection of occupied habitat. For
example:
BLM Lands With an RMP That Protects Gunnison Sage-Grouse
BLM lands that will be managed under the new range-wide Resource
Management Plan (RMP) amendment for Gunnison sage-grouse with
sufficient protections can be considered as providing habitat
protection.
Candidate Conservation Agreement With Assurances (CCAA)
Private lands already enrolled under the Candidate Conservation
Agreement for Gunnison sage-grouse that is administered by Colorado
Parks & Wildlife will be considered as providing habitat protection.
Enrollment in the Sage-Grouse Initiative (SGI)
Private lands managed under Conservation Plans that follow the
guidance of the Natural Resource Conservation Service's Sage-Grouse
Initiative (SGI) will be considered as providing habitat protection.
Enrollment in the Conservation Reserve Program (CRP)
The Service will consider private lands enrolled in the Farm
Service Agency's Conservation Reserve Program (CRP) within the Dove
Creek-Monticello satellite population as providing habitat protection
based on its assessment of the quality of habitat provided by CRP
practices.
The CRP State Acres for Wildlife Enhancement (SAFE) program allows
continuous sign-up and is designed to address State and regional high-
priority wildlife objectives. Producers within a SAFE area can submit
offers to voluntarily enroll acres in CRP contracts for 10-15 years. In
exchange, producers receive annual CRP rental payments, incentives, and
cost-share assistance to establish, improve, connect, or create higher
quality habitat. In Colorado, the goal of the Colorado Western Slope
Grouse CRP SAFE project is to restore and enhance habitat for the
Columbian sharp-tailed grouse, greater sage-grouse, and Gunnison sage-
grouse. The project seeks to enroll 12,600 acres in CRP.
Enrollment in CRP is limited by FSA to 25 percent of cropland in a
county, unless a waiver is granted. The enrollment caps for the Dove
Creek-Monticello satellite population counties are: San Juan County,
Utah 33,550 acres; Dolores County, Colorado, 22,152 acres; and San
Miguel County, Colorado, 5,404 acres.
Current enrollment in San Juan County is 33,654 acres. Three
additions could be made in San Juan County, Utah, to increase the
Gunnison sage-grouse conservation value of the CRP program: (1) The
addition of a CRP SAFE program targeting Gunnison sage-grouse would
make continuous signup available and could also provide additional
incentives for landowners; (2) A waiver to exceed the 25 percent
cropland limit to allow increased CRP enrollment and incentive to
create Gunnison sage-grouse habitat; and (3) The addition of sagebrush
and more forbs to the CRP seed mix would improve Gunnison sage-grouse
habitat more quickly than relying on natural reestablishment.
In Dolores County, Colorado, 6,431 acres of occupied habitat and
10,869 acres of potentially suitable habitat are currently enrolled in
CRP. In San Miguel County, Colorado, 303 acres of occupied habitat and
4,742 acres of potentially suitable habitat are currently enrolled in
CRP. The 2005 RCP identified the lack of sagebrush as an issue and
recommends that CRP target establishment of 5,000 acres of sagebrush
within 3 miles of leks in Utah and 3,000 acres of sagebrush within 6.5
km (4 mi) of leks in Colorado.
Protection Under Conservation Easements
Conservation easements with provisions that protect Gunnison sage-
grouse habitat will be considered as providing habitat protection on
private lands. The Service recommends that efforts to increase acreage
under conservation easements first prioritize areas closest to active
leks.
In San Miguel County and Montrose County, new conservation
easements should focus on the Miramonte Basin, Iron Mesa, and Gurley
Basin.
In the Dove Creek-Monticello population, the majority of occupied
habitat is privately owned (87 percent in Dove Creek; 95 percent in
Monticello). Conservation easements in the Dove Creek-Monticello
population should prioritize landowners participating in the
Conservation Reserve Program (CRP), if the habitat is recognized as
already providing a high conservation value for the population.
Targeted opportunities under the NRCS Agricultural Conservation
Easement Program (ACEP) could play a major role in restoring sagebrush
and understory grasses and forbs to provide the protection levels
needed for the population persistence.
Summary
An updated conservation strategy for the Gunnison sage-grouse
should reflect the complexity of the species' biology, the distribution
of the species across the landscape, and the diverse stakeholders who
are critical to success. The Service will assess not only population
and habitat status and trends, but also the degree to which current and
projected threats are addressed when determining the confidence in the
long-term
[[Page 69310]]
conservation of Gunnison sage-grouse. The status and trend of the total
population size of Gunnison sage-grouse as well as the status and trend
of the Gunnison Basin and satellite populations influence confidence in
the resilience and redundancy evaluation. The Service also needs to
know that sage-grouse habitat for the satellite populations are of
sufficient quality and quantity to support populations with a high
likelihood of persistence. Sufficient habitat quality and quantity
combined with resilient population levels could provide confidence that
the relative extinction risk in the future for the satellite
populations is sufficiently low. Finally, an assessment of habitat
quality and quantity for all the populations will highlight potential
limiting habitat factors and target conservation to efforts that should
yield the highest and most expedient impact on Gunnison sage-grouse
populations.
Required Determinations
National Environmental Policy Act (42 U.S.C. 4321 et seq.)
We have determined that environmental assessments and environmental
impact statements, as defined under the authority of the National
Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.), need not be
prepared in connection with listing a species as an endangered or
threatened species under the Endangered Species Act. We published a
notice outlining our reasons for this determination in the Federal
Register on October 25, 1983 (48 FR 49244).
Government-to-Government Relationship With Tribes
In accordance with the President's memorandum of April 29, 1994
(Government-to-Government Relations with Native American Tribal
Governments; 59 FR 22951), Executive Order 13175 (Consultation and
Coordination With Indian Tribal Governments), and the Department of the
Interior's manual at 512 DM 2, we readily acknowledge our
responsibility to communicate meaningfully with recognized Federal
Tribes on a government-to-government basis. In accordance with
Secretarial Order 3206 of June 5, 1997 (American Indian Tribal Rights,
Federal-Tribal Trust Responsibilities, and the Endangered Species Act),
we readily acknowledge our responsibilities to work directly with
tribes in developing programs for healthy ecosystems, to acknowledge
that tribal lands are not subject to the same controls as Federal
public lands, to remain sensitive to Indian culture, and to make
information available to tribes.
The Service consulted with the Ute Mountain Ute Tribe (Tribe) on
March 26, 2014, regarding the proposed listing of Gunnison sage-grouse
and proposed critical habitat designation, and potential impacts to
Tribal activities on Pinecrest Ranch (USFWS 2014d, entire). Owned by
the Tribe under restricted fee status, Pinecrest Ranch includes 18,749
ac of land in the Gunnison Basin population area west of Gunnison,
Colorado, including approximately 12,000 ac of occupied habitat for
Gunnison sage-grouse. The consultation was focused primarily on
potential exemptions from take of Gunnison sage-grouse on the ranch and
exclusion of the ranch from critical habitat designation. In
consideration of the information provided by the Tribe and Tribal
conservation efforts for Gunnison sage-grouse (see discussion in Factor
D), the Service is excluding the ranch from the critical habitat
designation (published elsewhere in today's Federal Register).
References Cited
A complete list of references cited in this rulemaking is available
on the Internet at http://www.regulations.gov and upon request from the
Western Colorado Field Office (see FOR FURTHER INFORMATION CONTACT).
Authors
The primary authors of this package are the staff members of the
Western Colorado Field Office.
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, Transportation.
Final Regulation Promulgation
Accordingly, we amend part 17, subchapter B of chapter I, title 50
of the Code of Federal Regulations, as follows:
PART 17--[AMENDED]
0
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 1531-1544; 4201-4245; unless
otherwise noted.
0
2. Amend Sec. 17.11(h) by adding an entry for ``Sage-grouse,
Gunnison'' to the List of Endangered and Threatened Wildlife in
alphabetical order under ``Birds'' to read as follows:
Sec. 17.11 Endangered and threatened wildlife.
* * * * *
(h) * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species Vertebrate
-------------------------------------------------------- population where Critical Special
Historic range endangered or Status When listed habitat rules
Common name Scientific name threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
Birds
* * * * * * *
Sage-grouse, Gunnison............ Centrocercus minimus U.S.A. (AZ, CO, NM, Entire............. T 854 17.95(b) NA
UT).
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * *
Dated: November 7, 2014.
Daniel M. Ashe,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2014-27109 Filed 11-19-14; 8:45 am]
BILLING CODE 4310-55-P