[Federal Register: April 18, 2006 (Volume 71, Number 74)]
[Rules and Regulations]               
[Page 19953-19982]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[[Page 19953]]


Part III

Department of the Interior


Fish and Wildlife Service


50 CFR Part 17

Endangered and Threatened Wildlife and Plants; Final Listing 
Determination for the Gunnison Sage-Grouse as Threatened or Endangered; 
Final Rule

[[Page 19954]]



Fish and Wildlife Service

50 CFR Part 17

Endangered and Threatened Wildlife and Plants; Final Listing 
Determination for the Gunnison Sage-Grouse as Threatened or Endangered

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final listing determination.


SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
final listing determination for the Gunnison sage-grouse (Centrocercus 
minimus) as threatened or endangered under the Endangered Species Act 
of 1973, as amended (Act). After reviewing the best available 
scientific and commercial information, we find that listing is not 
warranted. Thus, we no longer consider the species to be a candidate 
for listing. We ask the public to submit to us any new information that 
becomes available concerning the status of or threats to the species. 
This information will help us monitor and encourage the conservation of 
this species.

DATES: The determination announced in this document was made on April 
11, 2006. Although further listing action will not result from this 
determination, we request that you submit new information concerning 
the status of or threats to this species whenever it becomes available.

ADDRESSES: Comments and materials received, as well as supporting 
documentation used in the preparation of this final listing 
determination, will be available for inspection, by appointment, during 
normal business hours at the Western Colorado Ecological Services Field 
Office, U.S. Fish and Wildlife Service, 764 Horizon Drive, Building B, 
Grand Junction, Colorado 81506-3946. Submit new information, materials, 
comments, or questions concerning this species to the Service at the 
above address.

FOR FURTHER INFORMATION CONTACT: Allan Pfister, Western Colorado 
Supervisor (see ADDRESSES section), by telephone at (970) 243-2778, by 
facsimile at (970) 245-6933, or by electronic mail at 


Previous Federal Action

    On January 18, 2000, the Director of the Service designated the 
Gunnison sage-grouse as a candidate species under the Act, with a 
listing priority of 5. The Federal Register notice regarding this 
decision was not published until December 28, 2000 (65 FR 82310, 
December 28, 2000). Candidates are species for which the Service has 
determined that the species warrants listing as a threatened or 
endangered species, but listing is precluded by higher listing 
priorities for other species. A listing priority of 5 indicates that 
there is a high magnitude of threats, but they are considered non-
    On January 26, 2000, The American Lands Alliance, Biodiversity 
Legal Foundation, and others petitioned the Service to list the species 
(Webb 2000). On January 10, 2001, some of the same plaintiffs sued the 
Service alleging the Service had not made required petition findings. 
In 2003, the U.S. District Court ruled that the Service's determination 
that the Gunnison sage-grouse was a candidate constituted a 12-month 
finding on the petition (American Lands Alliance v. Gale A. Norton, 
C.A. No. 00-2339, (D.D.C., 2003).
    The 2003 Candidate Notice of Review elevated the species' listing 
priority number to 2 (69 FR 24876), as the imminence of the perceived 
threats had increased. The 2004 Candidate Notice of Review (70 FR 
24870) maintained the listing priority number as a 2.
    Plaintiffs amended their complaint in May 2004 to allege that the 
Service's warranted-but-precluded finding and decision not to emergency 
list the Gunnison sage-grouse were in violation of the Act. The parties 
filed a stipulated settlement agreement with the court on November 14, 
2005, which includes a provision that the Service would make a listing 
determination by March 31, 2006. On March 28, 2006, the plaintiffs 
agreed to a one week extension (April 7, 2006) for this determination.
    Section 4(b)(1)(A) of the Act requires us to consider the best 
scientific and commercial data available as well as efforts being made 
by States or other entities to protect a species when making a listing 
decision. To meet this standard we collected information on the 
Gunnison sage-grouse, its habitats, threats, and environmental factors 
affecting the species from a wide array of sources. Most of the 
available scientific literature on Gunnison sage-grouse is summarized 
in the Gunnison Sage-grouse Rangewide Conservation Plan, a document 
published in April 2005 under the auspices of the Gunnison Sage-grouse 
Rangewide Steering Committee [GSRSC]. The GSRSC is comprised of 
biologists from state and Federal agencies with responsibility for 
managing the Gunnison sage-grouse or its habitat. The scientific 
literature on Gunnison sage-grouse and its sagebrush habitats is 
limited. Where information on Gunnison sage-grouse life history was 
lacking, we used, as appropriate information on greater sage-grouse to 
analyze habitat usage, threats, and environmental factors affecting the 
Gunnison sage-grouse. In addition we received a substantial amount of 
unpublished information from other Federal agencies, States, counties, 
environmental organizations, and individuals. We also solicited 
information on all Federal, State, or local conservation efforts 
currently in operation or planned for the Gunnison sage-grouse or its 
    In April 2005, Colorado Division of Wildlife (CDOW) applied to the 
Service for a Gunnison sage-grouse Enhancement of Survival Permit 
pursuant to section 10(a)(1)(A) of the Act. The permit application 
included a proposed Candidate Conservation Agreement with Assurances 
(CCAA) between CDOW and the Service. The standard that a CCAA must meet 
is that the benefits of the conservation measures implemented 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. The CCAA, the permit application, and the Environmental 
Assessment were made available for public comment on July 6, 2005 (70 
FR 38977). Public comments and other internal comments from the Service 
and CDOW were incorporated into revisions of the CCAA and Environmental 
Assessment; the documents are scheduled to be finalized shortly. 
Landowners with eligible property in southwestern Colorado who wish to 
participate can voluntarily sign up under the CCAA and associated 
permit through a Certificate of Inclusion. These participants provide 
certain Gunnison sage-grouse habitat protection or enhancement measures 
on their lands. If the Gunnison sage-grouse is listed under the Act, 
the permit authorizes incidental take of Gunnison sage-grouse due to 
otherwise lawful activities in accordance with the terms of the CCAA 
(e.g., crop cultivation, crop harvesting, livestock grazing, farm 
equipment operation, commercial/residential development, etc.), as long 
as the participating landowner is performing activities identified in 
the Certificate of Inclusion. Although we strongly encourage continued 
conservation of the Gunnison sage-

[[Page 19955]]

grouse, we did not rely upon this CCAA to support our listing 

Species Information

    In this determination, we use information specific to the Gunnison 
sage-grouse where available. However, where such information is lacking 
we use information on life history, habitat requirements, and effects 
of threats on greater sage-grouse. Except where referenced, the 
following life history information is taken from the Schroeder et al. 
(1999) literature review on sage-grouse (Centrocercus spp.).
    The sage-grouse is the largest grouse in North America and was 
first described by Lewis and Clark in 1805 (Schroeder et al. 1999). 
Sage-grouse are most easily identified by their large size, dark brown 
color, distinctive black bellies, long, pointed tails and association 
with sagebrush habitats. They are dimorphic in size, with females being 
smaller. Both sexes have yellow-green eye combs, which are less 
prominent in females. Sage-grouse are known for their elaborate mating 
ritual where males congregate on strutting grounds called leks and 
``dance'' to attract a mate. During the breeding season males have 
conspicuous filoplumes (specialized erectile feathers on the neck), and 
exhibit yellow-green apteria (fleshy bare patches of skin) on their 
breasts (Schroeder et al. 1999).
    For many years sage-grouse were considered a single species. Young 
et al. (2000) identified Gunnison sage-grouse (Centrocercus minimus) as 
a distinct species based on morphological (Hupp and Braun 1991; Young 
et al. 2000), genetic (Kahn et al. 1999; Oyler-McCance et al. 1999), 
and behavioral (Barber 1991; Young 1994; Young et al. 2000) differences 
and geographical isolation. Based on these differences, the American 
Ornithologist's Union (2000) accepted the Gunnison sage-grouse as a 
distinct species. The current ranges of the two species are not 
overlapping (Schroeder et al. 2004). We have considered the Gunnison 
sage-grouse as a distinct species consistent with the petition under 
review here. We acknowledge that there are questions regarding the 
validity of this taxon, however it is not the purpose of this action to 
elucidate taxonomic questions. The purpose of this action is to 
determine the status of the taxon within the context of the ESA.
    Gunnison sage-grouse and greater sage-grouse have similar life 
histories and habitat requirements (Young 1994). Nesting success for 
Gunnison sage-grouse is highest in areas where forbs and grass covers 
are found below a sagebrush canopy cover of 15 to 30 percent (Young et 
al. 2000). These numbers are comparable to those reported for the 
greater sage-grouse (Connelly et al. 2000a). Connelly et al. (2000a) 
also state that nest success for greater sage-grouse is greatest where 
grass cover is present. Therefore, factors identified in the greater 
sage-grouse literature that affect nesting habitat quality can affect 
Gunnison sage-grouse nesting habitat in a similar manner if those 
factors occur within the range of the Gunnison sage-grouse. 
Characteristics of sage-grouse winter habitats are also similar through 
the range of both species (Connelly et al. 2000a). In winter, Gunnison 
sage-grouse are restricted to areas of 15 to 30 percent sagebrush 
cover, similar to the greater sage-grouse (Connelly et al. 2000a; Young 
et al. 2000). However, they may also use areas with more deciduous 
shrubs during the winter (Young et al. 2000).
    Dietary requirements of the two species also are similar, being 
composed of nearly 100 percent sagebrush in the winter (Schroeder et 
al. 1999; Young et al. 2000). Forbs and insects are important during 
the summer and early fall. Gunnison and greater sage-grouse do not 
possess muscular gizzards and, therefore, lack the ability to grind and 
digest seeds (Rasmussen and Griner 1938; Leach and Hensley 1954). 
Gunnison sage-grouse chick dietary requirements of insects and forbs 
also are expected to be similar to greater sage-grouse and other grouse 
species (Tony Apa, CDOW, pers. comm. 2005).
    In the spring, sage-grouse gather on traditional breeding areas 
referred to as leks (Patterson 1952). Lek displaying occurs from mid-
March through late May, depending on elevation (Rogers 1964). For 
Gunnison sage-grouse, 87 percent of all nests were located less than 6 
kilometers (km) (4 miles (mi)) from the lek of capture (Apa 2004). Mean 
clutch size for Gunnison sage-grouse is 6.8  0.7 eggs 
(Young 1994). Most eggs hatch in June, with a peak between June 10 and 
June 20. Renesting rates following the loss of the original nest appear 
very low in Gunnison sage-grouse, with one study reporting 4.8 percent 
(Young 1994).
    During the pre-egg laying period, female sage-grouse select forbs 
that have generally higher amounts of calcium and crude protein than 
sagebrush has (Barnett and Crawford 1994). Chicks are precocial and 
leave the nest with the hen shortly after hatching. Females with chicks 
move to areas containing succulent forbs and insects, often in wet 
meadow habitat, where cover is sufficiently tall to conceal broods and 
provide shade. The availability of food and cover are key factors that 
affect chick and juvenile survival. During the first 3 weeks after 
hatching, insects are the primary food of chicks (Patterson 1952; 
Klebenow and Gray 1968; Peterson 1970; Johnson and Boyce 1990; Johnson 
and Boyce 1991; Drut et al. 1994b; Pyle and Crawford 1996; Fischer et 
al. 1996b). Diets of 4- to 8-week-old greater sage-grouse chicks were 
found to have more plant material (Peterson 1970). Succulent forbs are 
predominant in the diet until chicks exceed 3 months of age, at which 
time sagebrush becomes a major dietary component (Klebenow 1969; 
Connelly and Markham 1983; Connelly et al. 1988; Fischer et al. 1996b).
    During late summer and early fall, intermixing of broods and flocks 
of adult birds is common and the birds move from riparian areas to 
sagebrush-dominated landscapes that continue to provide green forbs. 
From late autumn through early spring the diet of greater and Gunnison 
sage-grouse is almost exclusively sagebrush (Rasmussen and Griner 1938; 
Batterson and Morse 1948; Patterson 1952; Leach and Hensley 1954; 
Barber 1968; Wallestad et al. 1975; Young et al. 2000). Many species of 
sagebrush can be consumed (Remington and Braun 1985; Welch et al. 1988, 
1991; Myers 1992). Flock size in winter is variable (15 to 100+), and 
flocks frequently consist of a single sex (Beck 1977; Hupp 1987). 
During particularly severe winters, sage-grouse are dependent on tall 
sagebrush, which is exposed even above deep snow, providing a 
consistently available food source. In response to severe winters, 
Gunnison sage-grouse have been documented to move as far as 27 km (17 
mi) (Root 2002). The extent of movement varies with severity of winter 
weather, topography, and vegetation cover. Sage-grouse may travel short 
distances or many miles between seasonal ranges. Movements in fall and 
early winter (September-December) exceed 3 km (2 mi).
    In one study, Gunnison sage-grouse survival from April 2002 through 
March 2003 was 48 ( 7) percent for males and 57 ( 7) percent for females (Apa 2004). Higher survival rate of 
female sage-grouse may be due to sexual dimorphism (Schroeder et al. 
1999). Gunnison sage-grouse female survival in small isolated 
populations was 52 ( 8) percent, compared to 71 ( 11) percent survival in the Gunnison Basin, the only population 
with greater than 500 individuals (Apa 2004). Other factors affecting 
survival rates include year and age (Zablan 1993).

[[Page 19956]]


    Sage-grouse are sagebrush obligates (Patterson 1952; Connelly et 
al. 2000a). They depend on a variety of shrub-steppe habitats 
throughout their life cycle and are considered obligate users of 
several species of sagebrush (Patterson 1952; Braun et al. 1976; 
Schroeder et al. 1999; Connelly et al. 2000a; Connelly et al. 2004). 
Sagebrush serves as a primary food for adults year-round (Wallestad et 
al. 1975) and also provides cover for nests (Connelly et al. 2000a). 
Sage-grouse move between seasonal ranges based on suitable habitat 
availability. Connelly et al. (2000a) segregated habitat requirements 
into four seasons: (1) Breeding; (2) summer--late brood-rearing; (3) 
fall; and (4) winter. Depending on habitat availability and proximity, 
some seasonal habitats may be indistinguishable.
    Breeding habitat includes leks and pre-laying, nesting, and early 
brood-rearing areas. Male Gunnison sage-grouse attend leks from mid-
March to mid-May. Leks are typically in the same location from year to 
year; some Gunnison sage-grouse leks have been used since the 1950s 
(Rogers 1964). Leks are usually flat to gently sloping areas of less 
than 15 percent grade in broad valleys or on ridges (Hanna 1936; 
Patterson 1952; Giezentanner and Clark 1974; Wallestad 1975; Autenrieth 
1981; Klott and Lindzey 1989). Leks have good visibility and low 
vegetation structure (Tate et al. 1979; Connelly et al. 1981; Gates 
1985), and acoustical qualities that allow sounds of breeding displays 
to carry (Patterson 1952; Wiley 1973, 1974; Bergerud 1988; Phillips 
1990). Leks are often surrounded by denser shrub-steppe cover, which is 
used for escape, thermal, and feeding cover. Leks can be formed 
opportunistically at any appropriate site within or adjacent to nesting 
habitat (Connelly et al. 2000a) and, therefore, lek habitat 
availability is not considered to be a limiting factor for sage-grouse 
(Schroeder 1997). A relatively small number of dominant males accounts 
for the majority of breeding on each lek (Schroeder et al. 1999).
    The pre-laying period is from late-March to April. Pre-laying 
habitats for sage-grouse need to provide a diversity of vegetation 
including forbs that are rich in calcium, phosphorous, and protein to 
meet the nutritional needs of females during the egg development period 
(Barnett and Crawford 1994; Connelly et al. 2000a).
    Nesting occurs from mid-April to June. Gunnison sage-grouse 
typically select nest sites under sagebrush cover with some forb and 
grass cover (Young 1994), and successful nests were found in higher 
shrub density and greater forb and grass cover than unsuccessful nests 
(Young 1994). The sagebrush understory of productive sage-grouse 
nesting areas contains native grasses and forbs, with horizontal and 
vertical structural diversity that provides an insect prey base, 
herbaceous forage for pre-laying and nesting hens, and cover for the 
hen while she is incubating (Schroeder et al. 1999; Connelly et al. 
2000a; Connelly et al. 2004). Shrub canopy and grass cover provide 
concealment for sage-grouse nests and young, and are critical for 
reproductive success (Barnett and Crawford 1994; Gregg et al. 1994; 
DeLong et al. 1995; Connelly et al. 2004). Few herbaceous plants are 
growing in April when nesting begins, so residual herbaceous cover from 
the previous growing season is critical for nest concealment in most 
areas (Connelly et al. 2000a).
    Young (1994) found that radio-tracked Gunnison sage-grouse nested 
an average of 4.3 km (2.7 mi) from the lek nearest to their capture 
site, with almost half nesting within 3 km (2 mi) of their capture 
site. While earlier studies indicated that most greater sage-grouse 
hens nest within 3 km (2 mi) of a lek, more recent research indicated 
that many hens actually move much further from leks to nest based on 
nesting habitat quality (Connelly et al. 2004). Female sage-grouse have 
been documented to travel more than 20 km (13 mi) to their nest site 
after mating (Connelly et al. 2000a). Female Gunnison and greater sage-
grouse exhibit fidelity to nesting locations (Connelly et al. 1988; 
Young 1994; Lyon 2000, Connelly et al. 2004, Holloran and Anderson 
2005). The degree of fidelity to a specific nesting area appears to 
diminish if the female's first nest attempt in that area was 
unsuccessful (Young 1994; Connelly et al. 2004). However, there is no 
statistical indication that movement to new nesting areas results in 
increased nesting success (Connelly et al. 2004).
    Early brood-rearing habitat is found close to nest sites (Connelly 
et al. 2000a), although individual females with broods may move large 
distances (Connelly 1982; as cited in Connelly et al. 2000a). Young 
(1994) found that Gunnison sage-grouse with broods used areas with 
lower slopes than nesting areas, high grass and forb cover, and 
relatively low sagebrush cover and density. Broods frequently used hay 
meadows, but were often flushed from interfaces of wet meadows and 
habitats providing more cover, such as sagebrush or willow-alder 
(Salix-Alnus). Forbs and insects are essential nutritional components 
for sage-grouse chicks (Klebenow and Gray 1968; Johnson and Boyce 1991; 
Connelly et al. 2004). Therefore, early 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. 2004).
    As fall approaches sage-grouse move from riparian to upland areas 
and start to shift to a winter diet (GSRSC 2005). By late summer and 
into the early fall, individuals become more social, and flocks are 
more concentrated (Patterson 1952). This is the period when Gunnison 
sage-grouse can be observed in atypical habitat such as agricultural 
fields (Commons 1997). However, radio-tracking studies in the Gunnison 
Basin have found that broods typically do not use hay meadows further 
away than 50 meters (m) (165 feet [ft]) of the edge of sagebrush stands 
(Gunnison Basin Conservation Plan 1997).
    Movements to winter ranges are slow and meandering. Sagebrush stand 
selection in winter is influenced by snow depth (Patterson 1952; 
Connelly 1982 as cited in Connelly et al. 2000a) and in some areas, 
topography (Beck 1977; Crawford et al. 2004). Winter areas are 
typically characterized by canopy cover greater than 25 percent and 
sagebrush greater than 30 to 41 cm (12 to 16 in) tall (Shoenberg 1982) 
associated with drainages, ridges, or southwest aspects with slopes 
less than 15 percent (Wallestad 1975; Beck 1977). Lower flat areas and 
shorter sagebrush along ridge tops provide roosting areas. In extreme 
winter conditions, greater sage-grouse will spend nights and portions 
of the day burrowed into ``snow roosts'' (Back et al. 1987).
    Hupp and Braun (1989) found that most Gunnison sage-grouse feeding 
activity in the winter occurred in drainages and on slopes with south 
or west aspects in the Gunnison Basin. During a severe winter in the 
Gunnison Basin in 1984, less than 10 percent of the sagebrush was 
exposed above the snow and available to sage-grouse. In these 
conditions, the tall and vigorous sagebrush typical in drainages was an 
especially important food source.

Historical Distribution

    Based on historical records, museum specimens, and potential sage-
grouse habitat, Schroeder et al. (2004) concluded that Gunnison sage-
grouse historically occurred in southwestern Colorado, northwestern New 
Mexico, northeastern Arizona, and southeastern Utah. Accounts of 
Gunnison sage-grouse in Kansas and Oklahoma, as suggested by Young et 
al. (2000), are not

[[Page 19957]]

supported with museum specimens, and Schroeder et al. (2004) found 
inconsistencies with the historical records and the sagebrush habitat 
currently available in those areas. Applegate (2001) found that none of 
the sagebrush species closely associated with sage-grouse occurred in 
Kansas. He attributed historical, anecdotal reports as mistaken 
locations or misidentification of lesser prairie chickens. For these 
reasons, southwestern Kansas and western Oklahoma are not considered 
within the historic range of Gunnison sage-grouse (Schroeder et al. 
2004). The GSRSC (2005) modified the historic range from Schroeder et 
al. (2004), based on more complete knowledge of historic and current 
habitat and the distribution of the species (GSRSC 2005). Based on this 
information, the maximum Gunnison sage-grouse historical 
(presettlement) range is estimated to have been 55,350 square 
kilometers (sq km) (21,370 square miles [sq mi]) (GSRSC 2005). To be 
clear, only a portion of the historical range would have been occupied 
at any one time, while all of the current range is considered occupied. 
Also, we do not know what portion of the historical range was occupied, 
or what the total population was.
    Rogers (1964) qualitatively discussed a decrease in sagebrush range 
due to overgrazing from the 1870's until about 1934. Additional effects 
occurred as a result of newer range management techniques implemented 
to support livestock by the Bureau of Land Management (BLM), Soil 
Conservation Service, and U.S. Forest Service (Rogers 1964). Rogers 
(1964) discussed sagebrush eradication (by spraying and burning) in the 
1950s, and used two examples (Uncompaghre Plateau, Flattop Mountain in 
Gunnison County, CO) within the current range to illustrate the large 
acreages (3-5,000 acres) treated, but stated that long-term effects 
were yet to be determined. Rogers (1964) demonstrated a much broader 
distribution of sagebrush in Colorado than what currently exists. 
Rogers (1964) also presents maps that show decreases in distribution 
from previous literature.
    Much of what was once sagebrush was already lost prior to 1958. 
Through the use of low-level aerial photography, Oyler-McCance et al. 
(2001) documented a loss of only or 155,673 ha (20 percent) of 
sagebrush habitat from 1958 to 1993 within Gunnison sage-grouse range. 
Thirty-seven percent of the plots sampled underwent substantial 
fragmentation of sagebrush vegetation during that same time period. 
Oyler-McCance et al. (2001) stated that sage-grouse habitat in 
southwestern Colorado (the range of Gunnison sage-grouse) has been more 
severely impacted than sagebrush habitat elsewhere in Colorado. 
However, the Gunnison Basin was not as significantly affected as other 
    The Colorado River Storage Project (CRSP) resulted in construction 
of three reservoirs within the Gunnison Basin in the mid-late 1960s 
(Blue Mesa and Morrow) and mid-1970s (Crystal). Several projects 
associated with CRSP were constructed in this same general timeframe to 
provide additional water storage and resulted in the loss of an 
unquantified, but likely small, amount of sagebrush habitat. These 
projects provide water storage and, to a certain extent, facilitate 
agricultural activities throughout the range of Gunnison sage-grouse.
    Riebsame et al (1996) discussed a greater rural growth rate in 
Colorado from the 1970s through the 1990s, compared to the rest of the 
U.S., which has resulted in land use conversion. They noted a pattern 
of private ranches shifting to residential communities within Gunnison 
sage-grouse habitat. The Gunnison Basin Working Group Research Sub-
committee (February, 2006) cited two regions within the Basin to be of 
the highest priority for conservation easements due to development 
    In summary, a substantial amount of sagebrush habitat within the 
range of the Gunnison sage-grouse had been lost prior to 1960. In the 
years since, habitat loss and fragmentation has slowed, although 
development pressures have been on the rise. Conservation efforts are 
being developed to help address development-related issues.

Current Distribution and Population Estimates

    Gunnison sage-grouse currently occur in seven widely scattered and 
isolated populations in Colorado and Utah, occupying 4,720 sq km (1,820 
sq mi) (GSRSC 2005). 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 comparative 
summary of the seven populations is presented in Table 1.

[[Page 19958]]


[[Page 19959]]

                         Table 1.--Population Size, Extent of Occupied Habitat, Land Ownership, and Urban Development Pressures
                                      Population size       2005 population     Currently  occupied
       Name of  population           range  1995-2005*         estimate                area                Land ownership         Development pressure
Gunnison Basin Population........  2,203-4,763.........  4,763...............  240,000 hectares      51 percent BLM, 14         Gunnison County
                                                                                (ha) 593,000 (ac).    percent USFS, 2 percent    currently has a low
                                                                                                      NPS, 1 percent CDOW, 1     population density of 5
                                                                                                      percent Colorado State     people/sq mi in 2000
                                                                                                      Land Board, 31 percent     (GSRSC 2005), with
                                                                                                      private (GSRSC 2005).      projected growth rates
                                                                                                                                 ranging from .1 to 1.6
                                                                                                                                 percent per year. These
                                                                                                                                 rates result in a
                                                                                                                                 population increase of
                                                                                                                                 about 5700 people by
                                                                                                                                 2030 (41 percent or 7
                                                                                                                                 people/sq mi) (CDLA
                                                                                                                                 2004). A 30 percent
                                                                                                                                 housing increase is
                                                                                                                                 projected from 2000-
                                                                                                                                 2020 (GSRSC 2005).
San Miguel Basin Population......  206-446.............  334.................  40,500 ha (100,500    Dry Creek--57 percent      The population in San
                                                                                ac).                  BLM, 12 percent, CDOW, 1   Miguel County is
                                                                                                      percent, Colorado State    expected to double to
                                                                                                      Land Board, 30 percent     18 people/sq mi between
                                                                                                      private.                   2000 and 2030 (CDLA
                                                                                                     Hamilton Mesa--85 percent   2004), accompanied by a
                                                                                                      private, 11 percent        62 percent increase in
                                                                                                      Colorado State Land        housing units by 2020
                                                                                                      Board, 4 percent BLM.      (GSRSC 2005).
                                                                                                     Miramonte--76 percent
                                                                                                      private, 15 percent
                                                                                                      CDOW, 7 percent USFS, 2
                                                                                                      percent BLM.
                                                                                                     Gurley Reservoir--91
                                                                                                      percent private, USFS 4
                                                                                                      percent, BLM 3 percent,
                                                                                                      the Colorado State Land
                                                                                                      Board 2 percent.
                                                                                                     Beaver Mesa--99.5 percent
                                                                                                      private, 0.5 percent BLM.
                                                                                                     Iron Springs--89 percent
                                                                                                      private, 6 percent USFS,
                                                                                                      5 percent Colorado State
                                                                                                      Land Board (GSRSC 2005).
Monticello-Dove Creek Population.  162-510 (Combined)..  196 (162 Monticello   40,000 ha (98,920     Monticello--95 percent     The Monticello, UT group
                                                          and 34 Dove Creek).   ac) (Combined).       private, 4 percent BLM,    has approximately 2
                                                                                                      1 percent State of Utah    people/sq mi (GSRSC
                                                                                                      land.                      2005) with a projected
                                                                                                                                 increase of roughly 18%
                                                                                                                                 to 2600 people (2.4
                                                                                                                                 people/sq mi) by 2030
                                                                                                                                 (Utah Governor's Office
                                                                                                                                 of Planning and Budget
                                   123-280 (Monticello)  ....................  Monticello--28,500    Dove Creek--87 percent
                                                                                ha (71,000 ac).       privately owned, 13
                                                                                                      percent BLM (GSRSC 2005).
                                   10-358 (Dove Creek).  ....................  Dove Creek--11,500
                                                                                ha (28,000 ac).
Pi[ntilde]on Mesa Population.....  79-206..............  167.................  16,000 ha (39,000     70 percent private, 28     Population density of 55
                                                                                ac).                  percent BLM, 2 percent     people/sq mi in 2000
                                                                                                      USFS (GSRSC 2005).         (GSRSC 2005) with a
                                                                                                                                 projected increase to
                                                                                                                                 105 people/sq mi by
                                                                                                                                 2030 (CDLA 2004).

[[Page 19960]]

Crawford Population..............  118-314.............  191.................  14,000 ha (35,000     63 percent BLM, 13         Estimate of 24 people/sq
                                                                                ac).                  percent NPS, 24 percent    mi living in and near
                                                                                                      private (GSRSC 2005).      this population in 2000
                                                                                                                                 (GSRSC 2005). Montrose
                                                                                                                                 County contains the
                                                                                                                                 southeastern 75 percent
                                                                                                                                 of the current range of
                                                                                                                                 the Crawford
                                                                                                                                 population. The county
                                                                                                                                 was identified as one
                                                                                                                                 of the fastest growing
                                                                                                                                 counties in the
                                                                                                                                 country, with human
                                                                                                                                 population expected to
                                                                                                                                 double from 2000-2030
                                                                                                                                 (CDLA 2004) and housing
                                                                                                                                 expected to increase by
                                                                                                                                 68 percent by 2020. The
                                                                                                                                 northwestern 25 percent
                                                                                                                                 of the current range is
                                                                                                                                 in Delta County, which
                                                                                                                                 is projected to
                                                                                                                                 increase in population
                                                                                                                                 by 79 percent by 2030
                                                                                                                                 (CDLA 2004) with an
                                                                                                                                 increase in housing of
                                                                                                                                 58 percent by 2020
                                                                                                                                 (GSRSC 2005).
Cerro Summit-Cimarron-Sims Mesa    25-83...............  25..................  15,000 ha (37,000     43 percent private, 51     Population threats not
 Population.                                                                    ac).                  percent BLM, 6 percent     evaluated.
                                                                                                      CDOW (GSRSC 2005).
Poncha Pass Population...........  5-44................  44..................  8,300 ha (20,400 ac)  48 percent BLM, 26         Population threats not
                                                                                                      percent USFS, 24 percent   evaluated.
                                                                                                      in private holdings, 2
                                                                                                      percent Colorado State
                                                                                                      Land Board (GSRSC 2005).
* The numbers presented are the lowest and highest population estimates during the 11-year period. The lows and highs did not all fall in the same years
  for each population.

    Gunnison Basin Population--The Gunnison Basin is an intermontane 
basin that includes parts of Gunnison and Saguache Counties, Colorado. 
The current Gunnison Basin population is distributed across 
approximately 240,000 ha (593,000 ac), roughly centered on the town of 
Gunnison. Elevations in the area range from 2,300 to 2,900 m (7,500 to 
9,500 ft). Big sagebrush (Artemesia tridentata) dominates the upland 
vegetation and has a highly variable growth form depending on local 
site conditions. Up to 84 leks have been surveyed annually for breeding 
activity in the Gunnison Basin (CDOW, unpubl. lit. 2005a). 
Approximately 37 percent of these leks occur on private land and 63 
percent on public land, primarily BLM (GSRSC 2005). In 2005, 44 of 
these leks were active, 38 inactive, and 2 are of unknown status. 
Rogers (1964) stated that Gunnison County had one of the largest sage-
grouse populations in Colorado.
    San Miguel Basin Population--The San Miguel Basin population is in 
Montrose and San Miguel Counties in Colorado, and is composed of six 
groups using different areas--Dry Creek Basin, Hamilton Mesa, Miramonte 
Reservoir, Gurley Reservoir, Beaver Mesa, and Iron Springs. Some of 
these six areas are used year-round by sage-grouse, and others are used 
seasonally. Recent radiotelemetry studies have suggested that sage-
grouse in the San Miguel Basin move widely and between these areas (Apa 
2004; Stiver, unpubl. lit. 2005).
    Sagebrush habitat in the Dry Creek Basin area is patchily 
distributed and the understory is either lacking in grass and forb 
diversity or nonexistent. Where irrigation is possible, private lands 
in the southeast portion of Dry Creek Basin are cultivated. Sagebrush 
habitat on private land has been heavily thinned, or removed entirely 
(GSRSC 2005). Gunnison sage-grouse use the Hamilton Mesa area in the 
summer, but use during other seasons is unknown. Miramonte Reservoir 
occupied sage-grouse habitat is approximately 4,700 ha (11,600 ac) 
(GSRSC 2005). Sagebrush stands are generally contiguous with a mixed 
grass and forb understory. Occupied habitat at the Gurley Reservoir 
area is heavily fragmented and the understory is a mixed grass and forb 
community. Farming attempts in the early 20th century led to the 
removal of much of the sagebrush, although agricultural activities now 
are restricted primarily to the seasonal irrigation and sagebrush has 
reestablished in most of the failed pastures. However, grazing pressure 
and competition from introduced grasses have kept the overall sagebrush 
representation low (GSRSC 2005). Sagebrush stands in the Iron Springs 
and Beaver Mesa areas are contiguous with a mixed grass understory. The 
Beaver Mesa area has numerous scattered patches of oakbrush (Quercus 
    The 2005 population estimate for the entire San Miguel Basin was 
334 (CDOW, unpubl. lit. 2005b) on 9 leks. Rogers (1964) reported that 
all big sagebrush-dominated habitats in San Miguel and Montrose 
Counties were historically used by sage-grouse. The historic 
distribution was highly fragmented by forests, rocky canyons and dry 
basins void of sagebrush habitats.

[[Page 19961]]

    Monticello-Dove Creek Population--This population has two disjunct 
groups of Gunnison sage-grouse. Currently, the largest group is near 
the town of Monticello, Utah. Gunnison sage-grouse in this group 
inhabit a broad plateau on the northeast side of the Abajo Mountains 
with fragmented patches of sagebrush interspersed with large grass 
pastures and agricultural fields. The Utah Division of Wildlife 
Resources (UDWR) estimates that Gunnison sage-grouse currently occupy 
about 24,000 ha (60,000 ac) in the Monticello group. The 2005 
population estimate for Monticello was 162 individuals with 2 active 
and 2 inactive leks (G. Wallace, UDWR pers. comm. 2005). Leks in the 
Monticello area were first identified and counted in 1968.
    The Dove Creek group 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. 
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. Lek counts in the Dove Creek area were over 50 males in 
1999, suggesting a population of about 245 birds, but declined to 7 
males in 2005 (CDOW, unpubl. lit. 2005c). All leks are located in 
agricultural fields on private lands. 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; Apa 
2004). Rogers (1964) reported that all sagebrush-dominated habitats in 
Dolores and Montezuma Counties within Gunnison sage-grouse range in 
Colorado were historically used by sage-grouse.
    Pi[ntilde]on Mesa Population--The Pi[ntilde]on Mesa population 
occurs on the northwest end of the Uncompahgre Plateau in Mesa County, 
about 35 km (22 mi) southwest of Grand Junction, Colorado. Eight leks 
are known (CDOW, unpubl. lit. 2004). However, one is inactive and 
another was not active in 2005 (CDOW unpubl. lit. 2005d). The 
Pi[ntilde]on Mesa area may have additional leks, but the high 
percentage of private land, a lack of roads, and heavy snow cover 
during spring makes locating additional leks difficult. 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 Uncompaghre Plateau, southeast of Pi[ntilde]on Mesa proper (Rogers 
1964). Their current distribution has been substantially reduced from 
historic levels (GSRSC 2005).
    Crawford Population--The Crawford population of Gunnison sage-
grouse is 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. tridentata) and black sagebrush (A. nova) dominate the 
mid-elevation uplands (GSRSC 2005). The 2005 population estimate for 
Crawford is 191 (CDOW, unpubl. lit. 2005e). Currently there are four 
active leks in the Crawford population on BLM lands in sagebrush 
habitat adjacent to an 11-km (7-mi) stretch of road. This area 
represents the largest contiguous sagebrush-dominated habitat within 
the Crawford boundary (GSRSC 2005).
    Cerro Summit-Cimarron-Sims Mesa Population--This population is in 
Montrose County, Colorado. The Cerro Summit-Cimarron group is centered 
about 24 km (15 mi) east of Montrose. The habitat consists of patches 
of sagebrush habitat fragmented by oakbrush and irrigated pastures. 
Three leks are known in the Cerro Summit-Cimarron group, but only one 
was verified to be active in 2005. Rogers (1964) noted a small 
population of sage-grouse in the Cimarron River drainage, but did not 
report population numbers. He noted that lek counts at Cerro Summit in 
1959 listed four individuals.
    The Sims Mesa area about 11 km (7 mi) south of Montrose consists of 
small patches of sagebrush that are heavily fragmented by pinyon-
juniper, residential and recreational development, and agriculture. The 
one known lek in Sims Mesa is inactive. Rogers (1964) counted eight 
males in a lek count at Sims Mesa in 1960. It is not known if sage-
grouse move between the Cerro-Summit-Cimarron and Sims Mesa groups.
    Poncha Pass Population--The Poncha Pass sage-grouse population is 
located in Saguache County, approximately 16 km (10 mi) northwest of 
Villa Grove, Colorado. This population was established through the 
introduction of 30 birds from the Gunnison Basin in 1971 and 1972 
during efforts to reintroduce the species to the San Luis Valley (GSRSC 
2005). The known population distribution is in 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 extensive 
and continuous with little fragmentation; sagebrush habitat quality 
throughout the area is adequate (Nehring and Apa 2000). San Luis Creek 
runs through the area, providing a year-round water source and lush, 
wet meadow riparian habitat for brood-rearing. The 2005 Poncha Pass 
sage-grouse population estimate is 44 (CDOW, unpubl. lit. 2005f). The 
only current lek is located on BLM-administered land. In 1992, a CDOW 
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, CDOW transplanted 24 additional birds from the Gunnison 
Basin (Nehring and Apa 2000). In 2001 and 2002, 20 and 7 birds 
respectively also were moved to the Poncha Pass by CDOW (GSRSC 2005). 
Transplanted females have bred successfully (Apa, CDOW, pers. comm. 
2004) and display activity resumed on the historic lek in spring 2001.

Population Trends

    Trends in abundance were analyzed for individual populations and 
the species rangewide using male lek count data from CDOW and UDWR 
(Garton 2005). Due to inconsistencies in data collection over time, 
trend analyses were conducted for two time periods--the entire number 
of years lek data have been collected (1957-2005), and from 1995-2005 
when sampling methodologies have been more consistent. Raw data 
collected for 2005 show a large increase in the numbers of males 
attending leks. Because of this, the analyses were conducted both with 
and without 2005 data; estimates did not change significantly when the 
2005 lek counts were omitted in this analysis. 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. Similarly, the small Poncha Pass population was not analyzed 
because it has been surveyed for only 6 years and in that time the 
population was augmented with birds from Gunnison Basin.
    The long-term analysis (1957-2005) found that the rangewide 
population of Gunnison sage-grouse was neither increasing nor 
decreasing during that time period. Annual rates of change were highly 
variable, most likely as a result of sampling error rather than actual 
changes in population sizes. 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 
(Table 2). As with similar analyses conducted for the

[[Page 19962]]

greater sage-grouse (Connelly et al. 2004), density-dependent models 
appeared to more accurately describe observed population trends (Garton 

 Table 2.--Summary of Population Trends for the Gunnison Sage-Grouse \1\
                           Population                               of
Rangewide.......................................................   1.049
Gunnison Basin..................................................   1.05
Pi[ntilde]on Mesa...............................................   1.09
San Miguel Basin................................................   0.9
Crawford........................................................   0.999
Monticello......................................................   0.99
\1\ 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. The analysis is for 1995-2005 (data from
  Garton 2005).

    Because we relied on the population trend analyses conducted by 
Garton (2005), we asked six peer reviewers to evaluate the report. We 
received comments from five of the 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 substantial 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 an overall population decline. In discussing the historic 
distribution of Gunnison sage-grouse, we concluded that much of the 
habitat loss, and by inference population decline, occurred prior to 
    It was also suggested 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). However, to 
further subdivide the data analyzed into smaller units (i.e. 
subpopulations) would have compromised the statistical integrity of the 
analysis due to small sample sizes. 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 
    An identical population trend analysis was peer reviewed by the 
Ecological Society of America in the ``Conservation Assessment of 
Greater Sage-grouse and Sagebrush Habitats'' (Connelly et al. 2004). 
Additional clarifying information regarding model assumptions, the 
primary concern of the peer reviewers, was provided by Garton after the 
peer review was complete. Based on this late submission, and after 
careful review of the analysis, we believe that Garton (2005) 
constitutes the best currently available information.

Summary of Factors Affecting the Species

    Section 4 of the Act (16 U.S.C. 1533) and regulations (50 CFR part 
424) promulgated to implement the listing provisions of the Act set 
forth the procedures for adding species to the Federal lists. A species 
may be determined to be an endangered or threatened species due to one 
or more of the five factors described in section 4(a)(1). As part of 
our analysis, we chose, out of an abundance of caution, not to rely on 
the Cerro Summit-Cimarron-Sims Mesa and Poncha Pass populations and the 
Dove Creek group of the Monticello-Dove Creek population for the 
longterm conservation of the species because of their small, isolated 
status. We also determined that these populations do not comprise a 
significant portion of the Gunnison sage-grouse range. Therefore, these 
populations/group were not evaluated further for future threats. 
Although we are not relying on these populations/group for the longterm 
conservation of the species, we nonetheless believe that conservation 
of these populations is worthwhile, and we will continue to support and 
encourage those efforts. However, we analyze the threats applicable to 
the remaining populations/group to determine whether the species as a 
whole meets the definition of threatened or endangered.
    The Service considers the foreseeable future in Gunnison sage-
grouse to be between 30 and 100 years based on 10 Gunnison sage-grouse 
generations to 2 sagebrush habitat regeneration cycles. This is 
consistent with our 12-month finding for the greater sage-grouse (70 FR 
2244). Because the Gunnison sage-grouse has the same generation time 
and occupies habitat similar to the greater sage-grouse, we consider it 
prudent to use the same definition for the foreseeable future.

A. The Present or Threatened Destruction, Modification, or Curtailment 
of Its Habitat or Range

    Data indicate that the Gunnison sage-grouse was found in central 
and southwest Colorado, southeast Utah, northwestern New Mexico, and 
northeastern Arizona prior to European settlement (GSRSC 2005, modified 
from Schroeder et al. 2004). Gunnison sage-grouse currently occupy 
4,719 sq km (1,822 sq mi) in southwestern Colorado and southeastern 
Utah (GSRSC 2005, modified from Schroeder et al. 2004). The following 
describes the issues affecting Gunnison sage-grouse within their 
current range.
    Current Threats Due to Habitat Fragmentation: Habitat fragmentation 
is the separation or splitting apart of previously contiguous, 
functional habitat. Fragmentation of sagebrush habitats has been cited 
as a primary cause of the decline of sage-grouse populations (Patterson 
1952; Connelly and Braun 1997; Braun 1998; Johnson and Braun 1999; 
Connelly et al. 2000a; Miller and Eddleman 2000; Schroeder and Baydack 
2001; Aldridge and Brigham 2003; Connelly et al. 2004; Schroeder et al. 
2004). While sage-grouse are dependent on interconnected expanses of 
sagebrush (Patterson 1952; Connelly et al. 2004), data are not 
available regarding optimum or even minimum sagebrush patch sizes 
necessary to support sage-grouse populations. In addition, there is a 
lack of data to assess how fragmentation influences specific sage-
grouse life-history parameters such as productivity, density, and home 
    Oyler-McCance et al. (2001) documented loss and fragmentation of 
sagebrush vegetation in southwestern Colorado. In a genetic study of 
Gunnison sage-grouse populations, Oyler-McCance et al. (2005) concluded 
that gene flow among populations of Gunnison sage-grouse is limited.
    Notwithstanding the lack of specificity on effects of 
fragmentation, it is clear that as a whole, fragmentation can have an 
adverse effect on sage-grouse populations. The following sections 
examine activities that can contribute to habitat fragmentation to 
determine whether they threaten Gunnison sage-grouse habitat.

Conversion to Agriculture and Water Development

    In the mid-1800s, western rangelands were converted to agricultural 
lands on a large scale beginning with the series of Homestead Acts in 
the 1800s (Braun 1998; Hays et al. 1998), especially where suitable 
deep soil terrain and

[[Page 19963]]

water were available (Rogers 1964). Influences resulting from 
agricultural activities adjoining sagebrush habitats extend into those 
habitats, and include increased predation and reduced nest success due 
to predators associated with agriculture (Connelly et al. 2004).
    Agricultural conversion can provide some limited benefits for sage-
grouse. Some crops such as alfalfa (Medicago sativa) and young bean 
sprouts (Phaseolus spp.) are eaten or used for cover by sage-grouse (C. 
Braun, CDOW, pers. comm. 1998). However, crop monocultures do not 
provide adequate year-round food or cover (GSRSC 2005). Gunnison sage-
grouse will use hay pastures for foraging within about 50 m (165 ft) of 
the edge of the field but do not forage further into the pasture due to 
lack of suitable habitat (Gunnison Basin Conservation Plan 1997).
    In the Gunnison Basin approximately 17,328 ha (42,800 ac) or 8 
percent of the current range was converted to agricultural activities 
in the past and for the most part is no longer occupied (GSRSC 2005). 
Approximately 5,700 ha (14,000 ac) or 7 percent of the current range in 
the San Miguel Basin has been converted to agriculture and for the most 
part is unoccupied (GSRSC 2005). The arrangement of these converted 
lands has contributed to habitat fragmentation in these areas, although 
it is not negatively influencing sage-grouse numbers in this population 
(Garton 2005).
    Approximately 30 percent of the 40,048 ha (98,920 ac) of the 
current range in the Monticello-Dove Creek population has been 
converted to agriculture and for the most part is no longer occupied 
(GSRSC 2005). In the Monticello group, 43 percent has been converted to 
pasture (GSRSC 2005). San Juan County, Utah, where the Monticello group 
resides, also has approximately 15,000 ha (37,000 ac) enrolled in 
Conservation Reserve Program (CRP), of which about half is within 
current sage-grouse range (San Juan County Gunnison Sage-grouse Work 
Group [GSWG], unpubl. lit. 2005; GSRSC 2005). Under CRP, cropland is 
planted to pastureland and, except in emergency situations, not hayed 
or grazed. The CRP fields are used heavily by grouse as brood-rearing 
areas but vary greatly in plant diversity and forb abundance, and 
generally lack any shrub cover (GSRSC 2005). Sagebrush patches have 
progressively become smaller and more fragmented limiting the amount of 
available winter habitat for the Monticello group (GSRSC 2005). 
Significant use of CRP as nesting or winter habitat will require 
establishment of sagebrush stands in these fields. The CRP has 
protected this area from more intensive agricultural use and 
development, and approximately 16,000 ha (40,000 ac) of CRP are up for 
renewal under the Farm Bill in the next 2-3 years.
    Conversion to agriculture is limited in the Pi[ntilde]on Mesa area, 
with only 5 percent (500 ha (1,214 ac)) of the current range planted to 
grass/forb rangeland and for the most part no longer occupied (GSRSC 
2005). Sagebrush occurs in some areas that may be converted to 
grassland for livestock (BLM, unpubl. lit. 2005a), but the continued 
conversion is considered to be a minor impact in the foreseeable 
future. Habitat conversion in the Crawford area due to agricultural 
activities has been limited (GSRSC 2005).
    Although past conversion to agriculture has resulted in the loss of 
sagebrush habitat, we have no evidence to conclude that ongoing or 
anticipated agricultural conversion of sagebrush habitats is likely to 
threaten or endanger the Gunnison sage-grouse. Existing agricultural 
activities may fragment the species current range, but we have no data 
to determine that this is actually occurring, or is likely to occur.
    Past development of irrigation projects has also resulted in loss 
of sage-grouse habitat (Braun 1998). Reservoir development in the 
Gunnison Basin flooded 3,700 ha (9,200 ac or 1.5 percent) of likely 
sage-grouse habitat (S. McCall, Bureau of Reclamation, pers. comm. 
2005), and three other reservoirs inundated approximately 2 percent of 
habitat in the San Miguel Basin population area (J. Garner, CDOW, pers. 
comm. 2005). We are unaware of any plans for additional reservoir 
construction in the foreseeable future and do not consider water 
development a threat to the species.


    Impacts from roads may include direct habitat loss, direct 
mortality, creation of barriers to migration to seasonal habitats 
(Forman and Alexander 1998), facilitation of mammalian (Forman and 
Alexander 1998; Forman 2000) and corvid predation (Connelly et al. 
2000b; Aldridge and Brigham 2003; Connelly et al. 2004) and expansion 
into previously unused areas, spread of invasive weeds (Forman and 
Alexander 1998; Forman 2000; Gelbard and Belnap 2003; Knick et al. 
2003; Connelly et al. 2004), noise in the vicinity of leks (Braun 1986; 
Forman and Alexander 1998; Holloran 2005), and increased recreational 
use and associated human disturbances (Forman and Alexander 1998; 
Massey 2001; Wyoming Game and Fish Department 2003). Specific effects 
of these factors on sage-grouse are discussed below.
    Lyon (2000) suggested that roads may be the primary impact of oil 
and gas development to greater sage-grouse, due to their persistence 
and continued use even after drilling and production have ceased. Braun 
et al. (2002) suggested that daily vehicular traffic along road 
networks for oil wells can impact Gunnison and greater sage-grouse 
breeding activities based on a documented decrease in males at leks. 
Modeling done in Connelly et al. (2004) found that the number of active 
leks, lek persistence and lek activity increased with increasing 
distance from an interstate highway. Other than this single predictive 
model output, we have no quantitative information on the current impact 
of roads to Gunnison sage-grouse. It is unclear what specific factor 
relative to roads sage-grouse are responding to, and Connelly et al. 
(2004) caution that they have not included other potential sources of 
disturbance (e.g., powerlines) in their analyses.
    Roads may have additional indirect effects that result from birds' 
behavioral avoidance of road areas because of noise, visual 
disturbance, pollutants, and predators moving along them. The absence 
of screening vegetation in arid and semiarid regions further 
exacerbates any problems (Suter 1978). Male sage-grouse depend on 
acoustical signals to attract females to leks (Gibson and Bradbury 
1985; Gratson 1993). If noise interferes with mating displays, and 
thereby female attendance, it is possible that younger males will not 
be drawn to the lek and eventually leks will become inactive (Braun 
1986; Holloran 2005). Dust from roads and exposed roadsides can damage 
vegetation through interference with photosynthetic activities; the 
actual amount of potential damage depends on winds, wind direction, the 
type of surrounding vegetation and topography (Forman and Alexander 
1998). Chemicals used for road maintenance, particularly in areas with 
snowy or icy precipitation, can affect the composition of roadside 
vegetation (Forman and Alexander 1998). While all of these potential 
effects are actually occurring or whether they have actually affected 
sage-grouse populations individually or at a species level.
    Gunnison sage-grouse habitat is currently fragmented by a number of 
roads (BLM, unpubl. lit. 2005b, Colorado Department of Transportation 
(CDOT) 2004, Jim Ferguson, BLM, pers. comm. 2005, San Juan County GSWG,

[[Page 19964]]

unpubl. lit. 2005), and road development within Gunnison sage-grouse 
habitats has precluded sage-grouse movement between the resultant 
patches (Oyler-McCance et al. 2001). New roads and increased traffic on 
existing roads may cause some impact to the Dry Creek Basin birds in 
the San Miguel Basin, primarily due to ongoing gas field development 
and exploration on both the eastern and western edges of the current 
range. Increases in truck traffic have been noted on 24 km (15 mi) of 
roads that cross the center of the current range in Dry Creek Basin. 
However, only two sage-grouse have been killed on the roads in Dry 
Creek Basin since 2003 (CDOW, unpubl. lit. 2006). No paved roads occur 
in the current range for the Pi[ntilde]on Mesa population, but with 
projected human population increases of 91 percent by 2030 (Colorado 
Department of Local Affairs [CDLA] 2004), we anticipate that new or 
existing roads will be paved in the foreseeable future.
    This information suggests new roads may result in additional 
habitat loss and fragmentation. It may also increase disturbance and 
chance of direct mortality. However, based on the data available to us, 
we have no data to support that the effects of existing roads in 
general, and the new roads specifically will impact Gunnison sage 
grouse at the species level.


    The most detrimental effect that powerlines have is to provide a 
convenient perch for predators. There are reports that they can also 
directly affect sage-grouse by posing a collision and electrocution 
hazard (Braun 1998; Connelly et al. 2000a), and can have indirect 
effects by increasing predation (Connelly et al. 2004), fragmenting 
habitat (Braun 1998), and facilitating the invasion of exotic annual 
plants (Knick et al. 2003; Connelly et al. 2004). However, although 
death through collision and electrocution are widely referenced, only 
one citation actually provides data to support the claim with a report 
of three adult sage-grouse dying as a result of colliding with a 
telegraph line in Utah (Borell 1939). Both Braun (1998) and Connelly et 
al. (2000a) report that sage-grouse collisions with powerlines occur, 
although no specific instances were presented.
    In areas where the vegetation is low and the terrain relatively 
flat, power poles provide an attractive hunting and roosting perch, as 
well as nesting stratum for many species of raptors (Steenhof et al. 
1993; Connelly et al. 2000a; Manville 2002; Vander Haegen et al. 2002). 
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; Manville 2002). Raptors may actively seek out 
power poles where natural perches are limited. For example, within 1 
year of construction of a 596-km (373-mi) transmission line in southern 
Idaho and Oregon, raptors and common ravens (Corvus corax) began 
nesting on the supporting poles (Steenhof et al. 1993). Within 10 years 
of construction, 133 pairs of raptors and ravens were nesting along 
this stretch (Steenhof et al. 1993). The increased abundance of raptors 
and corvids within the current Gunnison sage-grouse range could result 
in increased predation (Oyler-McCance et al. 2001). Ellis (1985) 
reported that golden eagle predation on greater sage-grouse increased 
from 26-73 percent after completion of a transmission line within 200 m 
(656 ft) of an active sage-grouse lek in northeastern Utah. The lek was 
eventually abandoned. Ellis (1985) concluded that the presence of the 
powerline resulted in changes in sage-grouse dispersal patterns and 
fragmentation of the habitat. 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 growth rates, as 
measured by recruitment of new males onto the lek, compared to leks 
further from these lines (Braun et al. 2002). The presence of a 
powerline may fragment sage-grouse habitats even if raptors are not 
present. Braun (1998) found that use of otherwise suitable habitat by 
sage-grouse near powerlines increased as distance from the powerline 
increased for up to 600 m (1,969 ft) and reported that the presence of 
powerlines may limit sage-grouse use within 1 km (0.6 mi) in otherwise 
suitable habitat.
    Linear corridors through sagebrush habitats can facilitate the 
spread of invasive species, such as cheatgrass (Bromus tectorum) 
(Connelly et al. 2004). However, we were unable to find any information 
regarding the amount of invasive species incursion as a result of 
powerline construction.
    On 121,000 ha (300,000 ac) of BLM land in Gunnison Basin there are 
36 rights-of-way for power facilities, power lines, and transmission 
lines, which have resulted in the direct loss of 350 ha (858 ac) of 
occupied habitat (BLM, unpubl. lit. 2005c). A transmission line runs 
through the Dry Creek Basin group in the San Miguel Basin population, 
and the Beaver Mesa group has two. None of the transmission lines in 
the San Miguel Basin have raptor proofing (BLM, unpubl. lit. 2005d), 
nor do most distribution lines (Jim Ferguson, BLM, pers. comm. 2005). 
One major electric transmission line runs east-west in the northern 
portion of the current range of the Monticello group (San Juan County 
GSWG, unpubl. lit. 2005). Powerlines do not appear to be present in 
sufficient density to pose a significant threat to Gunnison sage-grouse 
in the Pi[ntilde]on Mesa population at this time. 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 (J. 
Ferguson, BLM, pers. comm. 2005). The projected human population growth 
rate in and near Gunnison sage-grouse populations is low (see 
discussion under urban development). Therefore we expect a low rate of 
increase in powerlines with a concomitant small increase in predation 
from raptors and corvids. We do not expect these to be substantial 
threats at the population level.


    Fences are used to delineate property boundaries and to manage 
livestock (Braun 1998; Connelly et al. 2000a). The effects of fencing 
on sage-grouse include direct mortality through collisions, creation of 
predator (raptor) perch sites, the potential creation of a predator 
corridor along fences (particularly if a road is maintained next to the 
fence), and incursion of exotic species along the fencing corridor 
(Call and Maser 1985; Braun 1998; Connelly et al. 2000a; Knick et al. 
2003; Connelly et al. 2004).
    Sage-grouse frequently fly low and fast across sagebrush flats and 
new fences can create a collision hazard (Call and Maser 1985). Thirty-
six carcasses of greater sage-grouse were found near Randolph, Utah, 
along a 3.2-km (2-mi) fence within 3 months of its construction (Call 
and Maser 1985). Twenty-one incidents of mortality through fence 
collisions near Pinedale, Wyoming, were reported in 2003 to the BLM 
(Connelly et al. 2004). Fence collisions continue to be identified as a 
source of mortality for both Gunnison and greater sage-grouse (Braun 
1998; Connelly et al. 2000a; Oyler-McCance et al. 2001; Connelly et al. 
2004, San Juan County GSWG, unpubl. lit. 2005), although effects on 
populations are not understood. Braun (1998) suggested that collision 
with fences, especially woven wire fences, was a potential factor in 
sage-grouse decline. Connelly et al. (2000a) noted that grouse have 
been observed hitting or narrowly missing fences and that grouse 
remains are frequently found next to fences. The impact of collisions 
on populations of grouse has not been investigated.

[[Page 19965]]

    Fences provide perch sites for avian predation and, depending on 
their design, may also cause habitat loss and fragmentation. Where 
there are maintained trails alongside the fence, invasive weeds may 
increase (Connelly et al. 2000a; Oyler-McCance et al. 2001; Braun et 
al. 2002; Gelbard and Belnap 2003; Knick et al 2003; Connelly et al. 
2004). Where sage-grouse avoid habitat adjacent to fences, presumably 
to minimize the risk of predation, habitat fragmentation occurs even if 
the actual habitat is not removed (Braun 1998).
    There are at least 1,540 km (960 mi) of fence within BLM lands 
within the Gunnison Basin (BLM, unpubl. lit. 2005e) and an unquantified 
amount on other land ownerships. While these fences contribute to 
habitat fragmentation in this area and increase the potential for loss 
of individual grouse through collisions or enhanced predation, such 
effects have been ongoing since the first agricultural conversions 
occurred in sage-grouse habitat. Because we do not expect a major 
increase in the number of fences and Gunnison sage-grouse populations 
are relatively stable in the affected areas, we do not believe fencing 
is a significant threat to Gunnison sage-grouse at the species level.

Urban Development

    It is estimated that 3-5 percent of all sage-grouse historical 
habitat in Colorado has been converted into urban areas (Braun 1998). 
Interrelated effects from urban/suburban development include 
construction of associated infrastructure (roads, powerlines, and 
pipelines), which has been discussed, as well as predation threats from 
the introduction of domestic pets and increases in predators subsidized 
by human activities (e.g., landfills). Urban expansion into rural areas 
also is resulting in direct habitat loss and conversion, as well as 
alteration of remaining sage-grouse habitats around these areas due to 
the presence of humans and pets (Braun 1998; Connelly et al. 2000a). 
Specific affects of these factors on sage-grouse are discussed below.
    U.S. Census Bureau projections show that human population growth 
varies widely across the current distribution of Gunnison sage-grouse 
(CDLA 2004). Public ownership in the Crawford area and Gunnison Basin, 
and portions of the San Miguel Basin will limit potential impacts from 
development in those particular areas. However, even these public lands 
are intersected by private lands. ``No development'' conservation 
easements may help alleviate potential impacts of the expansion effects 
of urban and suburban development (existing and contemplated 
conservation easements in the Gunnison sage-grouse range are addressed 
in more detail under State regulatory protection considerations in 
Factor D).
    Aldridge (2005) used spatial modeling to determine various habitat, 
climatic, and anthropogenic factors that influence greater sage-grouse 
nest and brood habitat selection and to determine nest and brood 
success. He determined that broods avoided habitats with a high density 
of urban development and areas close to cropland. A single human-use 
feature did not appear to affect nest occurrence but sage-grouse 
strongly avoided nesting in areas when roads, well sites, urban 
habitats, and cropland were analyzed in combination. Aldridge (2005) 
agreed with Fuhlendorf et al. (2002) that this may be due to predator 
avoidance behavior.
    It is possible that residential development that is not managed to 
account for the needs of the Gunnison sage-grouse could destroy and 
fragment habitat for the Gunnison Basin population. Gunnison County 
currently has a low population density of 5 people/sq mi in 2000 (GSRSC 
2005), with projected growth rates ranging from .1 to 1.6 percent per 
year. These rates result in a population increase of about 5,700 people 
by 2030 (41% or 7 people/sq mi) (CDLA 2004). A 30 percent housing 
increase is projected from 2000-2020 (GSRSC 2005). Growth from the town 
of Crested Butte, on the northern end of the Gunnison Basin population, 
is expanding southward. Population growth estimates are not available 
for the portion of Saguache County that comprises approximately 25 
percent of the Gunnison Basin population's current range, although 
county-wide the projected population growth from 3 people/sq mi in 2000 
(GSRSC 2005) to 2030 is 45 percent (CDLA 2004). Currently, an estimated 
100-500 people live in the Gunnison Basin portion of Saguache County so 
the estimated population in 2030 will be between 145 and 725 people.
    Dry Creek Basin is the only group within the San Miguel Basin 
population with significant Federal and State land ownership (70 
percent). This population is made up of six disjunct sage-grouse 
groups. San Miguel County had 9 people/sq mi in 2000 (GSRSC 2005); most 
residents live in the town of Telluride or several smaller communities, 
including Norwood. The population in San Miguel County is expected to 
double to 18 people/sq mi between 2000 and 2030 (CDLA 2004), 
accompanied by a 62 percent increase in housing units by 2020 (GSRSC 
2005). Based upon the location of current subdivided areas, expansion 
into sage-grouse habitat is certain without some action by local 
government (GSRSC 2005). Residential development is likely to affect 
the Iron Springs Mesa and Gurley Reservoir groups (GSRSC 2005). 
Subdivision development increased during 2003 and 2004 and at Gurley 
Reservoir, a 260-ha+ (640-ac+) area has been broken up into 16, 16-ha 
(40-ac) tracts for development. Approximately 8 percent of the current 
range for this portion of the San Miguel Basin population will be 
developed. Continued development in the area threatens to cause habitat 
loss, fragmentation, and future connection of the San Miguel Basin 
population to other Gunnison sage-grouse populations. The Miramonte 
Reservoir group has a long-term threat of housing development (GSRSC 
2005). However, the Dry Creek Basin group, which is the largest and 
principally in Federal ownership, has little expected threat from 
development (GSRSC 2005).
    The Monticello group of the Monticello-Dove Creek population is in 
San Juan County, Utah, which has approximately 2 people/sq mi (GSRSC 
2005) with a projected increase to 3.6 people/sq mi by 2030 (Utah 
Governor's Office of Planning and Budget 2005) and a 54 percent 
increase in housing by 2020 (GSRSC 2005). Almost all the current range 
in both States is in private ownership.
    The Pi[ntilde]on Mesa population is in Mesa County, which had a 
population density of 55 people/sq mi in 2000 (GSRSC 2005) with a 
projected increase to 105 people/sq mi by 2030 (CDLA 2004) and 56 
percent in housing units by 2020 (GSRSC 2005). Approximately 70 percent 
of the current range is in private ownership. Expansion of growth from 
the nearby city of Grand Junction poses a threat of permanent habitat 
loss and fragmentation. The eastern 33 percent of the current range 
(approximately 13,000 ha or 32,000 ac) is privately-owned and contains 
810 ha (2,000 ac) in tracts, each less than 65 ha (160 ac), and an 
additional 1,500 ha (3,600 ac) in tracts between 65 and 130 ha (160 and 
320 ac), all of which can be further subdivided (GSRSC 2005). However, 
19 percent of the private land containing all occupied habitat is 
currently in conservation easements with additional lands being 
negotiated for conservation easements with the landowners, thereby 
limiting the threat of development (See Factor D for further discussion 
of easements).
    There were an estimated 24 people/sq mi living in and near the 
Crawford Area population in 2000 (GSRSC 2005).

[[Page 19966]]

Montrose County contains the southeastern 75 percent of the current 
range of the Crawford population. The county was identified as one of 
the fastest growing counties in the country, with human population 
expected to double from 2000-2030 (CDLA 2004) and housing expected to 
increase by 68 percent by 2020. Growth will likely fragment and destroy 
current habitat and potential linkages to the San Miguel population 
(GSRSC 2005), creating further isolation of this population (see Factor 
E for further discussion). The northwestern 25 percent of the current 
range is in Delta County, which is projected to increase in population 
by 79 percent by 2030 (CDLA 2004) with an increase in housing of 58 
percent by 2020 (GSRSC 2005).
    Human population growth and housing development is occurring in all 
of the Gunnison sage-grouse populations and is projected to continue to 
do so over the next 2 decades. Some populations (Gunnison and Crawford) 
have public lands as potential buffers for the anticipated human 
population growth. Additionally, with the exception of the Pi[ntilde]on 
Mesa population, projected human population densities in all sage-
grouse populations are low and do not appear to pose a significant 
threat. At Pi[ntilde]on Mesa, the threat of development may be 
diminished by current conservation easements with additional easements 

Energy Development

    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 and electrical facilities 
(Connelly et al. 2004). Surveys for recoverable resources occur 
primarily through seismic activities, using vibroesis trucks or 
shothole explosives. Well pads vary in size from 0.10 ha (0.25 ac) for 
coalbed natural gas wells in areas of level topography to greater than 
7 ha (17 ac) for deep gas wells (Connelly et al. 2004). Pads for 
compressor stations require 5-7 ha (12-17 ac) (Connelly et al. 2004). 
Well densities and spacing are typically designed to maximize recovery 
of the resource and are administered by State agencies (Connelly et al. 
2004). Well densities and spacing on Federal lands are governed by land 
management plans which include resource analysis and mitigation 
requirements. All the sage grouse are considered species of special 
concern and effects on grouse and habitat are part of the 
considerations for permit conditions imposed by the BLM.
    Direct habitat losses result from construction of well pads, roads, 
pipelines, powerlines, and the crushing of vegetation during seismic 
surveys. As disturbed areas are reclaimed, sage-grouse may repopulate 
the area. However, re-population may take 20-30 years, as habitat 
conditions are not immediately restored (Braun 1998). For most 
developments, return to pre-disturbance population levels is not 
expected due to a net loss and fragmentation of habitat (Braun et al. 
2002). After 20 years, sage-grouse have not recovered to pre-
development numbers in Alberta, even though well pads in these areas 
have been reclaimed (Braun et al. 2002). In some reclaimed areas, sage-
grouse have not returned (Aldridge and Brigham 2003). However in 
Jackson County, Colorado, sage-grouse have repopulated, although not to 
the pre-development levels.
    Noise can drive away wildlife, cause physiological stress, and 
interfere with auditory cues and intraspecific communication, as 
discussed previously. Aldridge and Brigham (2003) reported that, in the 
absence of stipulations to minimize the effects, mechanical activities 
at well sites may disrupt sage-grouse breeding and nesting activities. 
Greater sage-grouse hens that bred on leks within 3 km (2 mi) of oil 
and gas development in the upper Green River Basin of Wyoming selected 
nest sites with higher total shrub canopy cover and average live 
sagebrush height than hens nesting away from disturbance (Lyon 2000). 
The author hypothesized that exposure to road noise associated with oil 
and gas drilling may have been one cause for the difference in habitat 
selection. However, noise could not be separated from the potential 
effects of increased predation resulting from the presence of a new 
road. Above-ground noise is typically not regulated to mitigate effects 
to sage-grouse or other wildlife (Connelly et al. 2004). Gunnison sage-
grouse were observed flushing from a lek when a compressor station 
switched on, disrupting breeding behavior (Jim Garner, CDOW, pers. 
comm. 2004). However, this was a single incident, and we have no 
information to conclude that noise from energy development poses a 
significant threat to the species.
    Water quality and quantity may be affected in oil and gas 
development areas. However, since, sage-grouse do not require free 
water (Schroeder et al. 1999) we anticipate that impacts to water 
quality from mining activities would have minimal effects on them.
    Increased human presence resulting from oil and gas development 
also can impact sage-grouse either through avoidance of suitable 
habitat, disruption of breeding activities, or increased hunting and 
poaching pressure (Aldridge and Brigham 2003; Braun et al. 2002; BLM 
2003). Sage-grouse also may be at increased risk for collision with 
vehicles simply due to the increased traffic associated with oil and 
gas activities (BLM 2003).
    Only a few studies have examined the effects of oil and gas 
development on sage-grouse. While each of these studies reported sage-
grouse population declines, specific causes for the negative impacts 
were not determined. In Alberta, Canada, the development of well pads 
and associated roads in the mid-1980s resulted in the abandonment of 
three greater sage-grouse lek complexes within 200 m (656 ft) of these 
features (Braun et al. 2002). Those leks have not been active since 
that time. A fourth lek complex has gone from three to one lek with 
fewer numbers of sage-grouse on it (Braun et al. 2002). The well pads 
have since been reclaimed, but greater sage-grouse numbers have not 
recovered (we do not have information on post-reclamation vegetation). 
Subsequent to the development of the Manyberries Oil Field in high 
quality greater sage-grouse habitat in Alberta, male sage-grouse counts 
fell to the lowest known level (Braun et al. 2002). Two additional leks 
were directly disturbed, and neither of these leks has been active 
within the past 10 years (Braun et al. 2002). The development of oil 
reserves in Jackson County, Colorado, was concurrent with decline of 
greater sage-grouse numbers in the oil field area (Braun 1998). Sage-
grouse populations still occur in at least one long-term oil field 
development in Colorado where leks are not within line-of-sight of an 
active well or powerline (Braun et al. 2002). Although the number of 
active leks has declined in this field, sage-grouse have been 
consistently documented there since 1973.
    Of particular relevance to estimating oil and gas development 
impacts is the fidelity of sage-grouse hens to nesting and summer 
brood-rearing areas demonstrated by Lyon and Anderson (2003). Hens that 
have successfully nested will return to the same areas to nest every 
year. If these habitats are affected by oil and gas development, there 
is a strong potential that previously successful hens will return but 
not initiate nesting (Lyon 2000). Depending on the number of hens 
affected, local populations could decline.

[[Page 19967]]

    The reauthorization of the Energy Policy and Conservation Act in 
2000 dictated reinventory of Federal oil and gas reserves, which 
identified extensive reserves in the Greater Green River Basin of 
Colorado, Utah, and Wyoming, and the San Juan Basin of New Mexico and 
Colorado (Connelly et al. 2004). Energy development on Federal (BLM and 
USFS) lands is regulated by the BLM and can contain conservation 
measures for wildlife species (see Factor D for a more thorough 
discussion). The BLM (1999) classified the area encompassing all 
Gunnison sage-grouse habitat for its gas and oil potential. Three of 
the populations have areas with high (San Miguel Basin, Monticello 
group) or medium (Crawford) oil and gas potential. San Miguel County, 
where much oil and gas activity has occurred in the last few years, 
ranked 8 out of 64 in counties producing natural gas in 2002 (Colorado 
Oil and Gas Conservation Commission 2004).
    In the current sage-grouse range in the Gunnison Basin, 33 percent 
of the area ranked as low potential with the remainder having no 
potential for oil and gas development (BLM 1999; GSRSC 2005). No 
federally-leased lands exist within the population area (BLM, unpubl. 
lit. 2005f). However, one active well and six inactive wells are on 
non-Federal lands in the current range in the northern part of the 
Gunnison Basin (BLM, unpubl. lit. 2005f).
    The entire San Miguel Basin population area is classified as having 
high potential for oil and gas development (BLM 1999; GSRSC 2005)). 
Natural gas exploration in the San Miguel Basin has increased in recent 
months (CDOW, unpubl. lit. 2005g), with 49 percent of the current range 
on public and private land with Federal leases for gas development 
(BLM, unpubl. lit. 2005f). As a general practice, all currently 
unleased BLM lands within the current sage-grouse range in the San 
Miguel Basin are being deferred for oil and gas leasing until 
completion of the Resource Management Plans (RMPs) covering the habitat 
for this population (anticipated in 2007 and 2008).
    The Colorado State Land Board (CSLB) offered four sections of State 
school section land for oil and gas leasing in the San Miguel Basin 
population in February 2006. One of these is in occupied habitat of the 
Miramonte Reservoir group and the other three are in the Dry Creek 
Basin group. The San Miguel County Board of Commissioners requested 
that they withdraw those sections or at least place a ``no surface 
occupancy'' prescription on the land with adherence to conservation 
measures in the RCP (San Miguel County, unpubl. lit. 2006). The CSLB 
stipulated that well pads would be placed out of Gunnison sage-grouse 
habitat [to the extent possible] on one parcel in Dry Creek Basin where 
the surface and the mineral rights are owned by the CSLB (Linda Luther, 
San Miguel County, pers. comm. 2006). However, the other three parcels 
are split estate (private surface, CSLB-owned minerals) and the CSLB 
was unwilling to, or believed they could not, put stipulations for 
sage-grouse on those parcels. San Miguel County will continue to work 
with the landowners, CSLB, and oil and gas companies to place 
stipulations on the parcels (Linda Luther, San Miguel County, pers. 
comm. 2006) but whether stipulations will occur is uncertain. 
Nonetheless, this illustrates a strong conservation commitment by the 
County for the San Miguel Basin population.
    One oil and gas operator, who holds several leases in the San 
Miguel Basin, has decided to temporarily abandon drilling on its leases 
in the Hamilton Mesa, Miramonte Reservoir, Gurley Reservoir, Beaver 
Mesa, and Iron Springs Mesa areas because they are not expected to be 
economically feasible. However, exploration and production may continue 
in the future (CDOW, unpubl. lit. 2005g). Fifty-one oil and gas wells 
have been developed in the current range in the San Miguel Basin. All 
but 1 is in the Dry Creek Basin and 47 are on federally-leased land 
(BLM, unpubl. lit. 2005f). Additional wells on existing leases are 
proposed for this area in the next 10 years. Five gas pipelines are 
proposed for this development, one of which is expected to transect 
winter habitat and another will remove habitat in places (BLM, unpubl. 
lit. 2005g). The exact locations of any future drill sites 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 group (CDOW, unpubl. lit. 
    The Monticello group is in an area of high energy potential (GSRSC 
2005). Oil and gas leases with State and Federal mineral rights have 
been acquired or applied for on over 2,000 ha (5,000 ac) (6 percent) in 
the current range (Tammy Wallace, BLM, pers. comm. 2005). One new well 
pad was constructed in 2005 (San Juan County GSWG, unpubl. lit. 2005) 
and additional drilling is expected to occur in the next few years. 
However, BLM is currently deferring new leases in the current range.
    No oil and gas wells are within the current range in the Pinon Mesa 
area, although oil and gas leases occupy 17 percent of this habitat 
(BLM, unpubl. lit. 2005f). The remaining portion of the current range 
has no potential for oil or gas in this area except for a small portion 
on the eastern edge of the largest habitat block (BLM 1999; GSRSC 
2005). The Crawford population is in an area with high to medium 
potential for oil and gas development (BLM 1999; GSRSC 2005). However, 
no Federal leases and only one well (on non-Federal lease property) are 
in the current range (BLM, unpubl. lit. 2005f). The BLM has deferred 
Federal oil and gas leases in the current range in this population 
until resource management plans addressing Gunnison Sage Grouse are 
adopted. Future development could occur on State and private land in 
the Crawford area under Colorado Oil and Gas Commission regulation and 
on BLM land if their future RMP allows it.
    In summary, some Gunnison sage-grouse habitat is in areas with high 
potential for oil and gas development, particularly in the San Miguel 
Basin. A few studies on greater sage-grouse reported population 
declines in response to oil and gas development (Braun et al. 2002; 
Lyon and Anderson 2003), although specific causes for the declines were 
not determined. A recent study of greater sage-grouse in Wyoming found 
that as oil and gas development increased (Holloran 2005). Negative 
impacts to active leks extended to a distance of 5 km (3 mi) from an 
active drilling rig. Similarly, juvenile male recruitment to impacted 
leks also fell. Nesting females avoided areas with high well densities, 
although site fidelity to previous nesting locations may result in 
delayed population response to the habitat changes associated with 
development. While some birds were displaced by the disturbance, 
Holloran (2005) also found that many sage-grouse discontinued breeding 
attempts, and others died at a higher rate than birds from unaffected 
areas. He concluded that natural gas field development contributes to 
localized greater sage-grouse extirpations, but that regional 
populations levels, although negatively impacted, are not as severely 
    Application of these impacts from gas development to the San Miguel 
and Crawford populations and Monticello group could threaten their 
long-term persistence. However, the immediate threat to Gunnison sage-
grouse is curtailed by BLM lease deferments. Additionally, available 
information suggests that economic infeasibility of extraction will act 
to minimize the likelihood this development will occur at a significant 
enough level to imperil Gunnison sage-grouse.
    Colorado has been the largest producer of coalbed methane in the

[[Page 19968]]

country since 2002, and production has increased (Cappa et al. 2005). 
Deposits exist under the current range of the San Miguel and Crawford 
populations (Cappa et al. 2005), although no wells have been drilled to 
date in those areas (D. Spencer, BLM, pers. comm. 2005) leading us to 
believe this does not represent a significant threat to these 
populations and therefore to the species.
    Renewable energy resources, such as windpower, require many of the 
same features for construction and operation as do nonrenewable energy 
resources. Therefore, we anticipate that potential impacts from direct 
habitat losses, habitat fragmentation through roads and powerlines, 
noise, and increased human presence (Connelly et al. 2004) will 
generally be the same as already discussed for nonrenewable energy 
development. Windpower may have additional mortalities resulting from 
sage-grouse flying into turbine rotors or meteorological towers 
(Erickson et al. 2001), although the magnitude of such losses is 
unquantified. One greater 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). 
During 3 years of monitoring operation, this is the only known sage-
grouse mortality at this facility.
    Current interest and speculation in wind energy exists in the 
Monticello area. A wind test tower (anemometer) has been erected at a 
site approximately 2.4 km (1.5 mi) from a lek (GSRSC 2005), and 
landowners in the area have been contacted by power company contractors 
about leases for wind power development. If wind turbines are placed 
near leks and other important habitat in the Monticello group, 
depending on the location and number of turbines, Gunnison sage-grouse 
in this area may be affected. We are not aware of any other wind energy 
development proposed throughout the rest of the Gunnison sage-grouse 
current range. We have no evidence that current or future wind energy 
development threatens or endangers the long-term persistence of the 


    Surface mining for any mineral resource (coal, uranium, copper, 
bentonite, gypsum, oil shale, phosphate, limestone, gravel, etc.) will 
result in direct habitat loss for Gunnison sage-grouse if the mining 
occurs in current sagebrush range. Direct loss of sage-grouse habitat 
also can occur if the overburden and/or topsoil resulting from mining 
activities are stored in sagebrush habitats. The actual effect of this 
loss depends on the quality, amount, and type of habitat disturbed, the 
scale of the disturbance, and the availability of adjacent habitats 
(Proctor et al. 1983; Remington and Braun 1991).
    Regulation of non-coal mining in the United States is at the 
discretion of the individual States. New vegetation types including 
exotic species may become established on mined areas (Moore and Mills 
1977), altering their suitability for sage-grouse. If reclamation plans 
call for the permanent conversion of the mined area to a different 
habitat type (e.g., agriculture) the habitat loss becomes permanent. 
Invasive exotic plants also may establish on the disturbed surfaces. 
Removal of the overburden and target mineral may result in changes in 
topography, subsequently resulting in changes in microclimates and 
microhabitats (Moore and Mills 1977). Additional habitat losses can 
occur if supporting infrastructure, such as roads, railroads, utility 
corridors, buildings, etc., become permanent landscape features after 
mining and reclamation are completed (Moore and Mills 1977), which is 
allowed in Colorado (Colorado Statute Title 34, Article 32) and Utah 
    Other indirect effects from mining can include reduced air quality 
from fugitive dust, degradation of surface water quality and quantity, 
disturbance from noise, human presence, and mortality from collision 
with mining equipment (Moore and Mills 1977; Brown and Clayton 2004). 
Fugitive dust could affect local vegetative and insect resources (Moore 
and Mills 1977). Most large surface mines are required to control 
fugitive dust, so these impacts are probably limited.
    Since sage-grouse do not require free water (Schroeder et al. 
1999), we anticipate that impacts to water quality from mining 
activities would have minimal population-level effects. The possible 
exception is degradation or loss of riparian areas, which could result 
in brood habitat loss. The effects on sage-grouse of noise from mining 
are unknown, but sage-grouse also depend on acoustical signals to 
attract females to leks (Gibson and Bradbury 1985; Gratson 1993). If 
noise does interfere with mating display and thereby female attendance, 
younger males will not attend the lek, and eventually leks will become 
inactive (Amstrup and Phillips 1977; Braun 1986). Mining also can 
impact sage-grouse through the increased presence of human activity, 
either through avoidance of suitable habitat adjacent to mines or 
through collisions with vehicles associated with mining operations 
(Moore and Mills 1977; Brown and Clayton 2004). However, we were unable 
to find any information regarding increased mortality of Gunnison sage-
grouse as a result of this effect.
    Within Gunnison sage-grouse current range, coal, uranium, and 
vanadium are the most commonly mined minerals and have begun to attract 
increased interest in recent years (Cappa et al. 2005). These minerals 
were mined historically in the San Miguel area and affected an unknown 
amount of the historical range of the Gunnison sage-grouse. Uranium 
deposits are within the current range of the San Miguel Basin 
population and Monticello group (Coker 2001; Cappa et al. 2005) and 
three mines near the San Miguel Basin population were reopened in 2004 
(Cappa et al. 2005). Due to the exploratory nature of this mineral 
activity to date and the somewhat speculative nature of its occurrence 
in the future, we do not believe that this activity will be a 
significant threat to the species in the foreseeable future.
    Six active hardrock, gravel or road fill mines are located on BLM 
land in sage-grouse habitat in the Gunnison Basin (BLM, unpubl. lit. 
2005c). Total disturbance, excluding roads, is 39 ha (96 ac). Two 
hundred ninety-one inactive or abandoned mines and numerous miles of 
roads have caused unquantified past habitat loss and fragmentation 
(BLM, unpubl. lit. 2005b), but future impact of hardrock, gravel, or 
road fill mines are likely limited.
    We conclude that present and future mining activities appear to be 
limited and do not pose a significant threat to Gunnison sage-grouse.


    Grazing is the dominant use of sagebrush rangelands in the West 
(Connelly et al. 2004); almost all sagebrush areas are managed for 
livestock grazing (Knick et al. 2003). Although we lack information on 
the proportion of occupied Gunnison sage-grouse habitat that is grazed, 
we expect that it is a vast majority. Excessive grazing by domestic 
livestock during the late 1800s and early 1900s, along with severe 
drought, significantly affected sagebrush ecosystems (Knick et al. 
2003). Although current livestock stocking rates are substantially 
lower than high historical levels (Laycock et al. 1996), long-term 
effects from this overgrazing, including changes in plant communities 
and soils, persist today. Although it is likely that livestock grazing 
and associated land treatments have altered plant composition, 
increased topsoil loss, and increased spread of exotic plants, the 
impacts on sage-grouse are not clear. Few studies have directly 
addressed the effect of

[[Page 19969]]

livestock grazing on sage-grouse (Beck and Mitchell 2000; Wamboldt et 
al. 2002; Crawford et al. 2004), and there is little direct 
experimental evidence linking grazing practices to sage-grouse 
population levels (Braun 1987, Connelly and Braun 1997). Rowland (2004) 
conducted a literature review and found no experimental research that 
demonstrates grazing alone is responsible for reduction in sage-grouse 
    The GSRSC (2005) could not find a direct correlation between 
historic grazing and reduced sage-grouse numbers. It has been 
demonstrated that the reduction of grass heights due to livestock 
grazing of sage-grouse nesting and brood-rearing habitat negatively 
affects nesting success by reducing cover necessary for predator 
avoidance (Gregg et al. 1994; Delong et al. 1995; Connelly et al. 
2000a). Nest success in Gunnison sage-grouse habitat is related to 
greater grass and forb height and shrub density (Young 1994). In 
addition, livestock consumption of forbs may reduce food availability 
for sage-grouse. This is particularly important for pre-laying hens, as 
forbs provide essential calcium, phosphorus, and protein. A hen's 
nutritional condition affects nest initiation rate, clutch size, and 
subsequent reproductive success (Connelly et al. 2000a). Livestock 
grazing can reduce the forage availability in breeding and brood-
rearing habitat, with possible subsequent negative effects on sage-
grouse populations (Braun 1987; Young 1994; Dobkin 1995; Beck and 
Mitchell 2000). Exclosure studies have demonstrated that domestic 
livestock grazing also reduces water infiltration rates and cover of 
herbaceous plants and litter, as well as compacting soils and 
increasing soil erosion (Braun 1998). This results in a change in the 
proportion of shrub, grass, and forb components in the affected area, 
and an increased invasion of exotic plant species that do not provide 
suitable habitat for sage-grouse (Miller and Eddleman 2000). Hulet 
(1983, as cited in Connelly et al. 2000a) found that heavy grazing 
could lead to increases in ground squirrel numbers; ground squirrel 
depredate sage-grouse nests. Thus, livestock stocking levels and season 
and duration of use are important factors of livestock operations 
related to impacts on sage-grouse include
    Other consequences of grazing include several related to livestock 
trampling. Outright nest destruction by livestock trampling does occur, 
and the presence of livestock can cause sage-grouse to abandon their 
nests (Rasmussen and Griner 1938; Patterson 1952; Call and Maser 1985; 
Crawford et al. 2004). Call and Maser (1985) indicate that forced 
movements of cattle and sheep could have significant effects on nesting 
hens and young broods caught in the path of these drives. Livestock 
also may trample sagebrush seedlings thereby removing a source of 
future sage-grouse food and cover (Connelly et al. 2000a), and 
trampling of soil by livestock can reduce or eliminate biological soil 
crusts making these areas susceptible to cheatgrass invasion (Mack 1981 
as cited in Miller and Eddleman 2000; Young and Allen 1997; Forman and 
Alexander 1998).
    Livestock grazing also may compete directly with sage-grouse for 
rangeland resources. Aldridge and Brigham (2003) suggest that poor 
livestock management in mesic sites results in a reduction of forbs and 
grasses available to greater sage-grouse chicks, thereby affecting 
chick survival. The effects of direct competition between livestock and 
sage-grouse depend on condition of the habitat and grazing practices.
    Development of springs and other water sources to support livestock 
in upland shrub-steppe habitats can artificially concentrate domestic 
and wild ungulates in important sage-grouse habitats, thereby 
exacerbating grazing impacts in those areas through vegetation 
trampling, etc. (Braun 1998). Diverting water sources has the secondary 
effect of changing the habitat present at the water source before 
diversion. This could result in the loss of either riparian or wet 
meadow habitat important to sage-grouse as sources of forbs or insects.
    Sagebrush removal to increase herbaceous forage and grasses for 
domestic and wild ungulates is a common practice in sagebrush 
ecosystems (Connelly et al. 2004). Herbicide, especially Tebuthiuron 
applications were commonly used to kill large expanses of sagebrush, 
but it also killed many forbs used for brood-rearing (Crawford et al. 
2004). Thinning, rather than removal, of sagebrush using Tebuthiuron 
has been the focus of some treatments (Emmerich 1985; Olson and Whitson 
    Sage-grouse response to herbicide treatments depends on the extent 
to which forbs and sagebrush are killed. Chemical control of sagebrush 
has resulted in declines of sage-grouse breeding populations through 
the loss of live sagebrush cover (Connelly et al. 2000a). Herbicide 
treatment also can result in sage-grouse emigration from affected areas 
(Connelly et al. 2000a), and has been documented to have a negative 
effect on nesting, brood carrying capacity (Klebenow 1970), and winter 
shrub cover essential for food and thermal cover (Pyrah 1972 and Higby 
1969 as cited in Connelly et al. 2000a). Carr and Glover (1970) found 
that greater sage-grouse would use block-sprayed areas for strutting 
but not for other activities. They found that adults would move the 1.6 
km (1.0 mi) across the sprayed areas but believed that movement across 
the area may cease as dead standing sagebrush deteriorated. They also 
determined that broods were impeded from moving to a previously used 
riparian area due to killing of the sagebrush between nesting sites and 
the riparian area. Winter use also did not occur in the area due to 
lack of live sagebrush for forage.
    Small treatments interspersed with non-treated sagebrush habitats 
did not affect sage-grouse use, presumably due to minimal effects on 
food or cover (Braun 1998). Also, application of herbicides in early 
spring to reduce sagebrush cover may enhance some brood-rearing 
habitats by increasing the coverage of herbaceous plant foods 
(Autenrieth 1981).
    Mechanical treatments are designed to either remove the above-
ground portion of the sagebrush plant (mowing, roller chopping, and 
rotobeating), or to uproot the plant from the soil (grubbing, 
bulldozing, anchor chaining, cabling, railing, raking, and plowing; 
Connelly et al. 2004). These treatments were begun in the 1930s and 
continued at relatively low levels to the late 1990s (Braun 1998). 
Mechanical treatments, if carefully designed and executed, can be 
beneficial to sage-grouse by improving herbaceous cover, improving forb 
production, and resprouting sagebrush (Braun 1998). However, adverse 
effects also have been documented (Connelly et al. 2000a). Mechanical 
treatments in blocks greater than 100 ha (247 ac), or of any size 
seeded with exotic grasses, degrade sage-grouse habitat by altering the 
structure and composition of the vegetative community (Braun 1998).
    For Gunnison sage-grouse, the best measure of potential grazing 
impacts is derived from monitoring habitat conditions in grazing 
allotments and comparing that information to grouse habitat objectives. 
BLM developed habitat objectives for Gunnison sage-grouse from habitat 
objectives in each of the local conservation plans. They are similar to 
the grazing management guidelines that were later developed for the RCP 
(GSRSC 2005). Where information is available, the comparison between 
BLM's habitat conditions and habitat objectives is presented below.
    Within the current range in the Gunnison Basin, 23 of 66 BLM 

[[Page 19970]]

allotments have sage-grouse habitat objectives incorporated into the 
allotment management plans or Records of Decision for permit renewals 
(BLM, unpubl. lit. 2005h). In 2002, 50 percent of the Wyoming big 
sagebrush/Indian ricegrass (Achnathrum hymenoides) vegetation, which 
accounts for a significant portion of the nesting/early brood-rearing 
habitat, met the desired condition on BLM lands in the area (GSRSC 
2005). In 2003, 75 percent of 32,000 ha (80,000 ac) of nesting/early 
brood-rearing habitat monitored met habitat objectives (BLM, unpubl. 
lit. 2004). Under 50 percent of the 579 km (360 mi) of riparian areas, 
which are important for brood-rearing, met desired conditions 
identified in the Gunnison Basin Conservation Plan (1997) and 85 
percent met short-term stubble height objectives (nesting cover) (BLM, 
unpubl. lit. 2004). In 2004, 23,000 ha (56,000 ac) were monitored 
within a 3-km (2-mi) radius of a lek, and less than 2 percent met the 
local (Gunnison Basin Conservation Plan 1997) objectives for grass 
stubble height (BLM, unpubl. lit. 2005i). However, grass growth may 
have been suppressed by effects of drought, which appeared to be 
impacting habitat in most populations in 2004 (See Factor E for further 
drought discussion).
    We were able to acquire information on grazing intensity for only 
the Dry Creek Basin group of the San Miguel Basin population. No sage-
grouse habitat objectives or conservation measures are in allotment 
management plans or grazing permits for BLM allotments in that area 
(BLM, unpubl. lit. 2005d and 2005g). Sagebrush patches there continue 
to succeed to a late-seral sagebrush community lacking in understory.
    Eight BLM grazing allotments totaling 2,700 ha (6,700 ac) occur 
within the current range in the Monticello group (San Juan County GSWG, 
unpubl. lit. 2005). Few or no habitat objectives have been incorporated 
into BLM allotment management plans, nor have changes in grazing 
intensity been implemented for sage-grouse in the group. No data are 
available on whether grazing lands on BLM or private land are meeting 
sage-grouse habitat objectives for the Monticello group. The CRP has 
provided a considerable amount of brood-rearing habitat in the 
Monticello group because of its forb component. Grazing of CRP in Utah 
occurred in 2002 under emergency Farm Bill provisions due to drought. 
Radio-collared males and non-brood-rearing females exhibited temporary 
avoidance of grazed fields during and after grazing (San Juan County 
GSWG, unpubl. lit. 2005), although one hen with a brood continued to 
use a grazed CRP field.
    Fifty grazing allotments on BLM land are within the current range 
in the Pi[ntilde]on Mesa population (BLM, unpubl. lit. 2005a). We do 
not know the extent of grazing on the private land within the 
Pi[ntilde]on Mesa sage-grouse range. Only three BLM allotments (6 
percent) have Gunnison sage-grouse habitat objectives incorporated into 
the allotment management plan or grazing permit in this area. We have 
no information on habitat conditions in any of the allotments in the 
population area.
    In the Crawford population there are nine BLM grazing allotments, 
totaling about 8,500 ha (21,000 ac) or 60 percent of the habitat. Sage-
grouse conservation measures have been incorporated into seven of the 
allotment plans. On BLM land in the Crawford population, Animal Unit 
Months have been reduced and grazing management was recently changed 
(BLM unpubl. lit. 2005d). The Gunnison Gorge Land Health Assessment 
showed that 34,000 out of 44,000 ha (84,000 out of 110,000 ac), or 76 
percent of the current range, met the land health standard for 
threatened and endangered species (including Gunnison sage-grouse 
habitat). The extent of livestock grazing on private land is unknown.
    In conclusion, habitat manipulations to improve livestock forage 
can affect sage-grouse habitat. In the Gunnison Basin, BLM habitat 
conditions are adequate for approximately 50 to 75 percent of the area 
measured, depending on the parameters and year they were measured. The 
Gunnison Basin population has been stable over time (see Table 2 and 
Garton 2005), suggesting that grazing is not negatively affecting the 
population in this area. In the Crawford area 76 percent of the current 
range met standards, so we do not consider grazing to be a threat 
there. Although we do not have specific information on the remaining 
BLM lands, it is reasonable to assume similar conditions exist on the 
remainder of the BLM lands. In the Monticello area, private lands 
enrolled in CRP are usually left ungrazed. We lack data on the extent 
of private land grazing on Gunnison Sage-Grouse habitat in the 
remainder of its range. However, based on the data available to us, we 
conclude that there is insufficient data that demonstrates grazing is a 
threat to the species.
    We lack adequate information on the effect of deer and elk grazing 
on Gunnison sage-grouse and their habitat to fully address this 
potential impact. 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) documented a decline in available 
perennial grasses as elk densities increased. Such grazing could 
negatively impact nesting cover for sage-grouse. Excessive but 
localized deer and elk grazing has been documented in the Gunnison 
Basin (BLM, unpubl. lit. 2005i; Paul Jones, CDOW, pers. comm. 2005). 
The winter range of deer and elk overlaps the year-round range of the 
Gunnison sage-grouse. Deer and elk herds were above the carrying 
capacity of their winter range before the 2002 drought and were not 
significantly reduced during or after (BLM, unpubl. lit. 2005i). 
However, no evidence exists that competition for resources is limiting 
Gunnison sage-grouse in the Gunnison Basin. Although grazing by deer 
and elk occurs in all population areas, information on overgrazing by 
deer or elk and its potential effect on other populations has not been 

Invasive Weeds

    Invasive species have been defined as those that are not native to 
an ecosystem and whose introduction causes, or is likely to cause, 
economic or environmental harm or harm to human health (Executive Order 
13112, 1999). Invasive species often cause declines in native plant 
populations by reducing light, water, and nutrients, and they grow so 
quickly that they outcompete other species (Wooten et al. 1996). Exotic 
plants can reduce and eliminate populations of plants that sage-grouse 
use for food and cover. Frequent fires with short intervals within 
sagebrush habitats favor invasion of cheatgrass, which is unsuitable as 
sage-grouse habitat (Schroeder et al. 1999). Cheatgrass then shortens 
the fire interval (from approximately 30 years down to 5 years), 
perpetuating its own persistence and spread, and exacerbating the 
effects of fire in remaining sage-grouse habitats (Whisenant 1990; 
Billings 1994; Grahame and Sisk 2002; Connelly et al. 2004). A 
cheatgrass invasion into sagebrush habitat can lead to an eventual 
conversion of sagebrush/perennial grass community to sagebrush/annual 
grass or annual grass rangeland (Connelly et al. 2000a; Miller and 
Eddleman 2000). Rehabilitation of an area to sagebrush after cheatgrass 
becomes established is extremely difficult (Connelly et al. 2004). In 
some cases cheatgrass invasion encourages other exotic species such as 
knapweed and thistle (Grahame and Sisk 2002).
    Cheatgrass has invaded areas in Gunnison sage-grouse range, 
supplanting sagebrush habitat. Connelly

[[Page 19971]]

et al. (2000a) indicated that some greater sage-grouse populations have 
been affected and some will decline due to projected, continuing spread 
of cheatgrass domination in the absence of effective management. There 
has not been a demonstrated change in fire cycle in any population of 
Gunnison sage-grouse, so they may not be as threatened as greater sage-
grouse. While all of the Colorado Gunnison sage-grouse counties have 
noxious weed programs, none identify cheatgrass as a noxious weed for 
control purposes (Colorado Department of Agriculture 2003). The BLM, on 
whose land many acres of cheatgrass occur, is currently restricted to 
application of 6 ha (15 ac) of an effective herbicide per Field Office 
per year, limiting their ability to control this noxious weed (BLM, 
unpubl. lit. 2005i).
    Approximately 14,249 ha (35,200 ac) have been invaded by cheatgrass 
in the Gunnison Basin, equaling 6 percent of the current range (BLM, 
unpubl. lit. 2005i) with 405 ha (1,000 ac) considered dominated by 
cheatgrass (Sandy Borthwick, BLM, pers. comm. 2005) despite past 
treatments to control this weed (Gunnison Watershed Noxious Weed 
Program, unpubl. lit. 2005). In addition, cheatgrass has been found at 
50 other locations and 21 roads or road segments throughout the 
Gunnison Basin population's range. Although disturbed areas contain the 
most weeds, they can readily spread into undisturbed habitat. Given its 
invasive nature, cheatgrass may increase in the Gunnison Basin in the 
future, but the actual extent or rate of increase is uncertain. 
Cheatgrass is present throughout much of the current range in the San 
Miguel Basin (BLM, unpubl. lit. 2005d). It is sparsely scattered in the 
five Gunnison sage-grouse groups east of Dry Creek Basin, which are at 
higher elevation, and does not appear to pose a serious threat to them 
(CDOW, unpubl. lit. 2005g). Because cheatgrass can readily dominate 
native plant communities at lower elevations (CDOW, unpubl. lit. 
2005g), it may affect the Dry Creek Basin group, which comprises 62 
percent of the San Miguel Basin population. Invasive species are 
present at low levels in the Monticello groups (San Juan County GSGWG, 
unpubl. lit. 2005). 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 (R. Lambeth, BLM, pers. comm. 2005). It occurs in the lower 
elevation areas below Pi[ntilde]on Mesa that were formerly Gunnison 
sage-grouse range. It invaded two small prescribed burns in or near 
occupied habitat conducted in 1989 and 1998 (BLM, unpubl. lit. 2005a), 
and continues to be a concern with any ground disturbing projects. Four 
invasive weedy forbs also occur in the area, but occupy less than 4 ha 
(10 ac) (BLM, unpubl. lit. 2005a). Invasive weeds, especially 
cheatgrass, occur primarily along roads, other disturbed areas, and 
isolated areas of untreated vegetation in the Crawford population. No 
current estimates of the extent of weed invasion are available (BLM, 
unpubl. lit. 2005d).
    Although invasive weeds, especially cheatgrass, have affected some 
sage-grouse habitat, the impacts do not appear to be threatening 
individual populations or the species rangewide. We have no basis for 
expecting on the potential spread of cheatgrass into sage grass 
habitat, and we have not information that suggests that it will be a 
threat in the future.

Fire and Fire Management

    There have been significant changes in fire frequency, 
distribution, and intensity since European settlement (Young et al. 
1979; Miller and Eddleman 2000). The effects of fire on sagebrush 
habitats vary according to the species and subspecies of sagebrush and 
other plant species present (e.g., the understory) and the frequency, 
size and intensity of fires. Widely variable estimates of mean fire 
intervals have been described in the literature--35-100 years (Brown 
2000), greater than 50 years for big sagebrush communities (McArthur 
1994), 12-15 years for mountain big sagebrush (Artemesia tridentata 
vaseyana) (Miller and Rose 1999), 20-100 years (Peters and Bunting 
1994), 10-110 years depending on sagebrush species or subspecies and 
specific geographic area (Kilpatrick 2000), and 13-25 years (Frost 1998 
cited in Connelly et al. 2004).
    Fire tends to extensively reduce the sagebrush component within the 
burned areas. Time needed for most sagebrush species and subspecies to 
reestablish after burning suggests they evolved in an environment where 
wildfire was infrequent (interval of 30-50 years) and patchy in 
distribution (Braun 1998). Prior to European settlement, fire patterns 
in sagebrush communities were patchy, particularly in Wyoming big 
sagebrush, due to the discontinuous and limited fuels and unburned 
islands that remained after a fire (Miller and Eddleman 2000). Huff and 
Smith (2000) noted that these unburned islands appear to be important 
to the future recolonization of the sagebrush community by providing 
sources of sagebrush seed. Where sagebrush habitat has become 
fragmented and limited, there is potential for fire to eliminate the 
existing seed source, reducing the likelihood of natural regeneration.
    A variety of techniques have been attempted at re-establishing 
sagebrush post-fire, with mixed success (Quinney et al. 1996, 
Livingston 1998). Restoration of the sagebrush biome following a fire 
has been complicated not only by the invasion of exotic annual plant 
species, but the difficulty associated with establishing sagebrush 
seedlings (Boltz 1994). Wirth and Pyke (2003) reported that forb 
response post-fire is dependant on the forb community pre-burn.
    A clear positive response of sage-grouse to fire has not been 
demonstrated (Braun 1998). A number of studies have found adverse 
effects to sage grouse populations resulting from fire. (Call and Maser 
1985; Rowland and Wisdom 2002; Nelle et al. 2000; Byrne 2002; Connelly 
et al. 2000c; Fischer et al. 1996a). However, Klebenow (1970), Gates 
(1983, as cited in Connelly et al. 2000c), Sime (1991 as cited in 
Connelly et al. 2000a), and Pyle and Crawford (1996) all indicated that 
fire could improve brood-rearing habitat.
    Three prescribed burns have occurred in the Gunnison Basin since 
1984, totaling 700 ha (1,700 ac). The fires created large sagebrush-
free areas that were further degraded by poor post-burn livestock 
management (BLM, unpubl. lit. 2005i). 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 negative 
impacts on sage-grouse. The burns were conducted for big game forage 
improvement, but Land Health Assessments in 2004, noted that sagebrush 
had died and largely been replaced with weeds (BLM, unpubl. lit. 
2005g). The 2002 Burn Canyon fire in the Dry Creek Basin and Hamilton 
Mesa areas created a short-term habitat loss of 890 ha (2,200 ac). Fire 
has apparently not occurred recently in the Monticello group.
    One wildfire in the Gunnison Basin burned 445 ha (1,098 ac) in June 
2002 (Sandy Borthwick, BLM, pers. comm. 2006). There appears to be a 
good response to the fire from grass and forbs. Mountain big sagebrush 
also appears to have responded well based on seedling establishment in 
seeded and non-seeded areas. Some cheatgrass, suspected to have come in 
with the sagebrush seed, was observed on the seeded sites but was 
sparse (Sandy Borthwick, BLM, pers. comm. 2006). At least four

[[Page 19972]]

wildfires in the last 20 years burned 39,300 ha (97,200 ac) in the 
current range in the Pi[ntilde]on Mesa area and created large expanses 
almost devoid of sagebrush and invaded by cheatgrass and Russian 
thistle (Salsola spp) (BLM, unpubl. lit. 2005a). Some wildfire 
suppression has occurred in sage-grouse habitat in the vicinity of 
residences. Fire occurs infrequently in the Crawford area. The 
Fruitland wildfire burned 240 ha (600 ac) of pinyon-juniper and old 
sagebrush in 1996. Two efforts to reseed the area with sagebrush and 
native forbs and grasses failed and the area is now dominated by 
cheatgrass (BLM, unpubl. lit. 2005d). Spread of cheatgrass into other 
areas is an increasing threat due to its establishment in the burned 
    Where fire suppression has occurred, sagebrush communities may 
advance successionally to pinyon pine and juniper (Burkhardt and 
Tisdale 1969; Young and Evans 1981; Miller and Rose 1995; Miller et al. 
2000; Wrobleski and Kauffman 2003), eventually resulting in a near 
total loss of shrubs and sage-grouse habitat (Miller and Eddleman 
2000). Gambel oak invasion as a result of fire suppression also has 
been identified as a potential threat to Gunnison sage-grouse (CDOW, 
unpubl. lit. 2002). Trees provide perches for raptors; consequently, 
Gunnison sage-grouse avoid areas with pinyon-juniper (Commons et al. 
    Native tree or shrub encroachment on 11,336 ha (28,000 ac) or 5 
percent of the current range has occurred in the Gunnison Basin. 
Oakbrush encroachment is a potential threat in the San Miguel Basin, 
especially in the five easterly and higher elevation groups. 
Approximately 2,955 ha (7,300 ac) or 9 percent of the current range in 
these areas are dominated by oakbrush. Mountain shrubs also have 
encroached on about 3,280 ha (8,100 ac) or 9 percent of habitat in the 
San Miguel Basin population (GSRSC 2005). No pinyon-juniper dominated 
areas are within the current range.
    The Monticello area has 1,170 ha (2,889 ac) or 5 percent of the 
current range dominated by oakbrush (GSRSC 2005). Pinyon 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 there has been no quantification or mapping 
of the encroachment (San Juan County GSWG, unpubl. lit. 2005). A 
relatively recent invasion of pinyon and juniper trees between the Dove 
Creek and Monticello groups appears to be contributing to their 
isolation from each other (GSRSC 2005).
    About 1,600 ha (3,935 ac) of trees and shrubs dominate 16 percent 
of the current range in the Pi[ntilde]on Mesa area (GSRSC 2005). In 
addition to limiting habitat, tree and shrub encroachment is further 
isolating Pi[ntilde]on Mesa from the Crawford and San Miguel 
populations, thereby impacting connectivity and maintenance of genetic 
diversity (see discussion under Factor E). Approximately 9 percent of 
the 1,300 ha (3,200 ac) of the current range in the Crawford population 
is classified as dominated by pinyon-juniper (GSRSC 2005). However, BLM 
(unpubl. lit. 2005d) estimates that as much as 20 percent of the 
population area is occupied by pinyon-juniper. The Crawford population 
also has about 400 ha (953 ac) or 3 percent of oakbrush-dominated land 
in the current range (GSRSC 2005).
    Although fire suppression has likely caused low to moderate levels 
of native tree and shrub encroachment in the populations we considered, 
none of the encroachment is sufficient to pose a significant threat to 
the Gunnison sage-grouse at a population or rangewide level. Fires can 
cause spread of weeds and burn suitable sage-grouse habitat, but they 
do not threaten the species currently and we do not anticipate that 
they will in the future. Fires can be beneficial by rejuvenating forbs 
and grasses and reducing encroachment of native trees and shrubs.

Conclusion for Factor A

    Habitat fragmentation has affected the exchange of individuals 
among populations of Gunnison sage-grouse. Population isolation is most 
pronounced in Pinon Mesa and Monticello. There also is some evidence 
that the Monticello and Dove Creek groups have recently been separated 
from each other by habitat changes; however, there is no evidence that 
habitat fragmentation has limited exchange of sage-grouse within other 
populations, including the San Miguel Basin population which has six 
groups separated by 1-4 air miles.
    Forty-three percent of the occupied habitat in the Monticello group 
was converted to agriculture in the past, but little conversion is 
expected there in the future. Other occupied population areas have had 
lower percentages of past conversions with no current or future 
conversion expected. There is evidence that Gunnison sage-grouse will 
not use agricultural fields further than about 50 m (160 ft) from the 
edge for foraging but no evidence that agricultural conversion 
currently threatens the sage-grouse rangewide. Reservoirs caused 
fragmentation and/or loss of a small percentage of habitat in the 
Gunnison Basin population and the Gurley and Miramonte groups in the 
San Miguel Basin population. However, there is no evidence that 
reservoir development has caused range-wide or population-wide threats 
to the Gunnison sage-grouse.
    Other than two direct mortalities in the San Miguel Basin 
population, we were unable to find any data substantiating effects of 
roads to impacts on Gunnison sage-grouse populations. Based on the 
stable population trend, the current network of roads does not appear 
to be a threat to the species, and we have no information that 
indicates that future road development will pose a threat to the 
species rangewide. Despite the presence of powerlines in all 
populations there also is no evidence that they are threatening 
Gunnison sage-grouse populations rangewide or within populations.
    Urban or exurban development does not appear to be a threat to the 
sage-grouse based on the low human population densities in all but one 
county with Gunnison sage-grouse. Projections of human population 
growth and housing development are not known to be a rangewide threat.
    High potential for oil and gas development only exists in the San 
Miguel Basin population and Monticello group; high to medium potential 
exists in the Crawford population. Low or no potential exists in the 
Gunnison Basin and Pinon Mesa populations. Energy development on 
Federal lands can contain conservation measures for wildlife species 
(see Factor D for a more thorough discussion). We have no evidence that 
oil and gas development will threaten the Gunnison sage-grouse 
rangewide in the foreseeable future. Other energy development 
activities, such as wind turbine development, are not expected to cause 
a threat to the Gunnison sage-grouse rangewide in the foreseeable 
future. Additionally, coal or hardrock mining appears to pose little 
threat to occupied habitat.
    Although overgrazing can affect habitat, it is unclear whether 
effects from current livestock grazing management practices, such as 
reduction of vegetation below suitable conditions or spread of weeds 
threaten the Gunnison sage-grouse at a population or rangewide level. 
Cheatgrass may impact sage-grouse habitat in nearly all Gunnison sage-
grouse populations. However, there has not been a demonstrated change 
in fire cycle in any population, nor is it documented that cheatgrass, 
at its current distribution and density, will threaten the Gunnison 
sage-grouse in the foreseeable future. Invasive weeds

[[Page 19973]]

other than cheatgrass occur in some populations but at levels that do 
not cause a threat to the Gunnison sage-grouse.
    Fires can cause spread of weeds and burn suitable sage-grouse 
habitat, but also may be beneficial by rejuvenating forbs and grasses 
and reducing encroachment of native trees and shrubs. Fire can be both 
beneficial and detrimental depending on location, size, and intensity 
and is not expected to be a rangewide threat in the foreseeable future. 
Although there has been low to moderate levels of native tree and shrub 
encroachment in nearly all the populations, most likely as a result of 
fire suppression, none of the encroachment is great enough to cause a 
documented threat to the Gunnison sage-grouse at a rangewide level.
    Although various factors discussed in this section are believed to, 
or could potentially be, impacting the populations, these factors have 
not caused significant declines in the species rangewide. Thus, based 
on the best scientific and commercial data available, we have concluded 
that destruction, modification, or curtailment of its habitat or range 
does not threaten or endanger the Gunnison sage-grouse throughout all 
or a significant portion of its range in the foreseeable future.

 Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes


    Studies suggest that recreational hunting of sage-grouse may be 
compensatory (i.e., harvest replaces mortality that would have happened 
otherwise due to causes such as predation; or mortality is compensated 
by increased productivity (Crawford 1982)), have no measurable effect 
on sage-grouse densities (Braun and Beck 1996), or may be additive 
(i.e., harvest adds more deaths per year to the total otherwise 
attributable to other causes, and is not compensated by increased 
productivity (Zunino 1987; Connelly et al. 2000a)). Johnson and Braun 
(1999) concluded that harvest mortality may be additive for sage-grouse 
if adult females and young birds sustain the highest hunting mortality 
within a population. No studies have demonstrated that regulated 
hunting is a primary cause of widespread reduced numbers of greater 
sage-grouse (Connelly et al. 2004).
    Hunting of Gunnison sage-grouse is regulated by the State wildlife 
agencies (GSRSC 2005). Hunting in the Gunnison Basin appears to have 
been compensatory, as it had little if any impact on the population 
(CDOW, unpubl. lit. 2005g). However, sage-grouse hunting was eliminated 
in the Gunnison Basin in 2000 due to concerns with meeting population 
objectives as suggested in the Gunnison Basin Conservation Plan (1997). 
It is not known if hunting contributed to the failure to meet these 
objectives. Hunting has not occurred in the other Colorado populations 
of Gunnison sage-grouse since 1995 when the Pinon Mesa area was closed 
(GSRSC 2005). Utah has not allowed hunting since 1989. Both States have 
committed to disallow hunting until the species is no longer a 
candidate for listing or no longer federally-listed and will only 
consider hunting if populations can be sustained (GSRSC 2005). With 
this finding that situation will no longer be applicable. However, the 
Gunnison Basin Plan calls for a minimum of 500 birds before hunting 
will occur. Although that level is substantially exceeded in the 
Gunnison Basin, we believe the States sensitivity to the status of the 
species would preclude them from opening a hunting season until at 
least a majority of the populations have achieved such a status. We do 
not anticipate hunting to be opened in the foreseeable future in the 
smaller populations, or in the near future in the Gunnison Basin. 
Furthermore, any hunting will be restricted to only 5-10 percent of the 
fall population, and will be structured to limit harvest of females to 
the extent possible (GSRSC 2005). Public input will be considered when 
determining if hunting seasons should be reinstated (GSRSC 2005). We 
are not aware of any studies or other data that demonstrate that 
poaching (illegal harvest) has contributed to Gunnison sage-grouse 
population declines in either State.

Lek Viewing

    The Gunnison sage-grouse is a newly designated species, which 
prompts bird watchers to view it for their ``life lists'' and may lead 
to disturbance in commonly known leks. Daily human disturbances on 
sage-grouse leks could cause a reduction in mating, and some reduction 
in total production (Call and Maser 1985). Boyko et al. (2004, as cited 
in GSRSC 2005) determined that 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. Smaller 
lek sizes have been hypothesized to be less attractive to females, 
thereby conceivably reducing the numbers of females mating there. 
Disturbance during the peak of mating also could result in some females 
not breeding (GSRSC 2005). Lek viewing might affect nesting habitat 
selection by females (GSRSC 2005), 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).
    The BLM closed a lek in the Gunnison Basin to viewing in the late 
1990s due to declining population counts which were perceived as 
resulting from recreational viewing activities, although no scientific 
studies were conducted (BLM, unpubl. lit. 2005i; GSRSC 2005). A 
comparison of male counts on a designated viewing lek versus male 
counts on other leks in the general area, show that the viewing lek's 
counts followed the same trend line as leks in the rest of the area 
(GSRSC 2005). Lek viewing protocols on designated leks have generally 
been followed (GSRSC 2005). Two lek-viewing tours are organized and led 
by UDWR per year in the Monticello group without noticeable effects 
(Guy Wallace, UDWR, pers. comm. 2006). Data collected by CDOW indicates 
that controlled lek visitation also has not impacted greater sage-
grouse (GSRSC 2005).

Scientific Research

    Gunnison sage-grouse have been the subject of scientific research 
studies, some of which included the capture and handling of the 
species. Few, direct mortalities have occurred during recent studies 
and it does not appear that research is having any significant impacts 
on the sage-grouse (Apa 2004; CDOW, unpubl. lit. 2005g). Most research 
is conducted in the Gunnison and San Miguel Basin populations; the two 
largest populations. Based on the available information, we believe 
scientific research on Gunnison sage-grouse is a relatively minor 
impact, with only short-term effects to individuals in localized areas.

Conclusion for Factor B

    We have no evidence suggesting that hunting has resulted in 
overutilization of Gunnison sage-grouse. Future hunting restrictions 
should adequately conserve Gunnison sage-grouse. Based on limited data 
it appears that lek viewing has not affected the Gunnison sage-grouse 
and lek viewing protocols designed to reduce disturbance have generally 
been followed. Scientific research appears to be limited to short-

[[Page 19974]]

term impacts of individuals in localized areas and is not a rangewide 
threat. We know of no overutilization for commercial or educational 
purposes. Thus, based on the best scientific and commercial data 
available, we have concluded that overutilization for commercial, 
recreational, scientific, or educational purposes does not threaten or 
endanger the sage-grouse throughout all or a significant portion of its 
range in the foreseeable future.

C. Disease or Predation


    Nothing has been published about the types or pathology of diseases 
in Gunnison sage-grouse. However, multiple bacterial and parasitic 
diseases have been documented in greater sage-grouse (Patterson 1952; 
Schroeder et al. 1999). Some early studies have suggested that greater 
sage-grouse populations are adversely affected by parasitic infections 
(Batterson and Morse 1948). 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 (Connelly et 
al. 2004). 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. 
    Parasites also have been implicated in greater sage-grouse mate 
selection, with potentially subsequent effects on the genetic diversity 
of this species (Boyce 1990; Deibert 1995). Connelly et al. (2004) note 
that while these relationships may be important to the long-term 
ecology of greater sage-grouse, they have not been shown to be 
significant to the immediate status of populations. However, Connelly 
et al. (2004) have suggested that diseases and parasites may limit 
isolated sage-grouse populations such as most of the Gunnison sage-
grouse populations. However, we have no evidence indicating that 
bacterial or parasitic diseases are affecting Gunnison sage-grouse 
individuals or populations.
    Greater sage-grouse also are subject to a variety of bacterial, 
fungal, and viral pathogens. The bacteria Salmonella spp., has caused 
mortality in the greater sage-grouse; the bacteria is apparently 
contracted through exposure to contaminated water supplies around 
livestock stock tanks (Connelly et al. 2004). Other bacteria found in 
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). We have no 
reason to expect that mortality and exposure risk are different in 
Gunnison sage-grouse.
    West Nile virus (WNv; Flavivirus) was first diagnosed in greater 
sage-grouse in 2003, and has been shown to affect their survival rates. 
Experimental results, combined with field data, suggest that a 
widespread WNv infection could negatively affect greater sage-grouse 
(Naugle et al. 2004; Naugle et al. 2005). Summer habitat requirements 
of sage-grouse potentially increase their exposure to WNv. Sage-grouse 
hens and broods congregate in mesic habitats in the mid- to late 
summer, thereby placing them in the same potential habitats as the WNv 
mosquito (Culex spp.), vector when the mosquitoes are likely to be 
active. Surface water sources that have been created for agricultural, 
livestock, and energy and mining activities may increase the contact 
between sage-grouse and the mosquito vector. To date, WNv has not been 
documented in Gunnison sage-grouse despite the presence of WNv-positive 
mosquitoes in all counties throughout their range (Colorado Department 
of Public Health 2004; U.S. Centers for Disease Control and Prevention 
2004). Although WNv may be a potential threat, the data available to 
date suggest that it is not a significant threat to Gunnison sage-


    Predation is the most commonly identified cause of mortality in 
sage-grouse (Bergerud 1988; Schroeder et al. 1999; Connelly et al. 
2000b). The composition and density of predator communities can vary 
greatly across space and time (Greenwood 1986; Johnson et al. 1989; 
Sargeant et al. 1993; Sovada et al. 1995). The effect of predation on 
the demographic structure and population fluctuations of Gunnison sage-
grouse is unknown will depend on the composition of the predator 
community, grouse population levels, and habitat condition. In a study 
of nesting Gunnison sage-grouse, Young (1994) documented only 1 
predation event in 37 nesting attempts. Predation on greater sage-
grouse has been well documented. Predators of adult greater sage-grouse 
include coyotes (Canis latrans), bobcats (Lynx rufus), weasels (Mustela 
spp.), golden eagles, red-tailed hawks (Buteo jamaicensis), Swainson's 
hawks (B. swainsoni), and ferruginous hawks (B. regalis) (Hartzler 
1974; Schroeder et al. 1999; Schroeder and Baydack 2001). Avian 
predators, primarily corvids (Corvus spp.), were major predators of 
greater sage-grouse nests in Idaho (Autenrieth 1981) and Washington 
(Vander Haegen 2002), while ground squirrels and badgers (Taxidea 
taxus) were major nest predators in Wyoming (Patterson 1952). Most 
mammalian predation is on eggs; only coyotes and red foxes (Vulpes 
vulpes) are likely to prey on all sage-grouse life stages (GSRSC 2005). 
Young (1994) found that the most common predators of Gunnison sage-
grouse eggs were weasels, ground squirrels, coyotes, and corvids. Most 
other raptor predation of sage-grouse is on juveniles and older age 
classes (GSRSC 2005).
    Predation rates vary seasonally. The period of highest mortality 
for yearling and adult males occurs during the lekking season, as they 
are very conspicuous while performing their mating display. Adult 
female greater sage-grouse are most susceptible to predators while on 
the nest or during brood-rearing when they are with young chicks 
(Schroeder and Baydack 2001). Autenrieth (1981) concluded that 
predation of eggs was the most important population constraint in Idaho 
at that time, and this appears to be the case for Gunnison sage-grouse, 
based on limited data (Young 1994). Schroeder and Baydack (2001) 
suggest that high variation in nest success may be due to nest 
predators. Nest predation may be higher, more variable, and have a 
greater impact on small, fragmented Gunnison sage-grouse populations 
(GSRSC 2005).
    The population viability analysis of Gunnison sage-grouse (GSRSC 
2005) found that mortality of chicks and breeding-age hens contributed 
substantially to increasing the relative probability of extinction 
because these two groups contribute most significantly to population 
productivity. Gregg et al. (2003a, 2003b) found that chick predation 
mortality in greater sage-grouse ranged from 10 to 51 percent from 
2002-2003 on three study sites in Oregon. The juvenile mortality rate, 
during the first few weeks after hatching, has been estimated to be 63 
percent (Wallestad 1975 in Schroeder and Baydack 2001). While chicks 
are very vulnerable to predation during this period, other causes of 
mortality, such as weather, are included in this estimate.
    Female Gunnison sage-grouse with nests that were predated nested in 
sites with lower shrub density and lower forb and grass cover (Young 
1994). Habitat alteration that reduces cover for young greater sage-
grouse chicks can increase

[[Page 19975]]

the rate of predation on this age class (Schroeder and Baydack 2001).
    Increasing residential development increases the likelihood that 
feral cats (Felis domesticus) and dogs (Canis domesticus) will be 
introduced into local Gunnison sage-grouse populations. Development 
also can contribute to increased populations of predators (e.g., red 
foxes, American crows (Corvus americanus)) that are frequently 
associated with altered landscapes (GSRSC 2005). Agricultural 
development, landscape fragmentation, and human populations have the 
potential to increase predation pressure by forcing birds to nest in 
marginal habitats, by increasing travel time through habitats where 
they are vulnerable to predation, and by increasing the diversity and 
density of predators (Ritchie et al. 1994; Schroeder and Baydack 2001; 
Connelly et al. 2004; Summers et al. 2004). Where greater sage-grouse 
habitat has been altered in localized areas, the influx of predators 
can limit populations (Gregg et al. 1994; Braun 1998; DeLong et al. 
1995; Schroeder and Baydack 2001). Habitat fragmentation and the 
resultant predation increase may be a limiting factor for the Gunnison 
sage-grouse (Oyler-McCance et al. 2001).
    Municipal solid waste landfills have been shown to contribute to 
increases in common raven populations (Knight et al. 1993; Restani et 
al. 2001). Ravens are known to prey on sage-grouse and have been 
considered a restraint on sage-grouse population growth in some 
locations (Batterson and Morse 1948; Autenrieth 1981). However, no 
studies could be found that linked landfill presence, common raven 
populations, and sage-grouse population levels.
    The effect of predation on the fluctuations and viability of sage-
grouse populations has never been investigated (Connelly and Braun 
1997; Connelly et al. 2000b; Schroeder and Baydack 2001). Research 
conducted to determine survival and nest success in greater sage-grouse 
concluded that predation typically does not limit sage-grouse numbers 
(Connelly and Braun 1997; Connelly et al. 2000a; Connelly et al. 2000b; 
Wambolt et al. 2002). This conclusion is supported by evidence showing 
that predator removal does not have long-lasting effects on sage-grouse 
population size or stability over large regions (Cote and Sutherland 
1997; Schroeder et al. 1999; Wambolt et al. 2002). For example, Slater 
(2003) demonstrated that coyote control failed to produce an effect on 
greater sage-grouse nesting success in southwestern Wyoming. In their 
review of literature regarding predation, Connelly et al. (2004) 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. However, both studies indicated that low nest 
success due to predation was ultimately related to poor nesting 
habitat. Connelly et al. (2004) further noted that the idea that 
predation is not a widespread factor depressing sage-grouse populations 
is supported by studies of nest success rates, by the relatively high 
survival of adult birds, and by the lack of an effect on nesting 
success as a result of coyote control.
    In a study of 28 radio-collared Gunnison sage-grouse in the 
Monticello group, 11 birds died, but only 4 of these could be 
attributed to predation by coyotes or eagles (San Juan County GSWG, 
unpubl. lit. 2005). However, demographic studies of Gunnison sage-
grouse in the San Miguel Basin population suggests, but does not 
conclusively prove, that predation may be affecting this population 
(CDOW, unpubl. lit. 2005g). No information is available for the other 
populations considered.

Conclusion for Factor C

    No rangewide or population level impacts of bacterial, viral, 
fungal, or parasitic diseases on Gunnison sage-grouse have been 
reported, including WNv. Predation is occurring at some level in all 
populations, but we have no evidence to suggest that it is a population 
or rangewide threat to Gunnison sage-grouse. Thus, based on the best 
scientific and commercial data available, we have concluded that 
disease and predation do not threaten or endanger the sage-grouse 
throughout all or a significant portion of its range in the foreseeable 

D. The Inadequacy of Existing Regulatory Mechanisms

Local Laws and Regulations

    Approximately 43 percent of occupied Gunnison sage-grouse habitat 
is privately owned (GSRSC 2005). Gunnison County and San Miguel County, 
Colorado, are the only entities that have ordinances within the 
species' range that provide a level of conservation consideration 
specifically for the Gunnison sage-grouse or their habitats on private 
land (Dolores County 2002; Mesa County, unpubl. lit. 2003; Montrose 
County 2003). In 2001, Gunnison County, Colorado developed Land Use 
Resolutions (LUR) to be consistent with the Memorandum of Agreement 
(MOA) signed for the Gunnison Basin Conservation Plan in 1998 (Gunnison 
County 2001). In the MOA, Gunnison County agreed to ``* * * reasonably 
consider sage-grouse conservation actions in its regulation of land use 
* * *'' and to implement the Gunnison Basin Conservation Plan to the 
best of their ability. The County is attempting to utilize this LUR to 
optimize sage-grouse conservation. In 2003, the LUR was revised 
slightly to allow two houses on 35 acres rather than one house without 
County review, thereby increasing the housing density that could occur 
in sage-grouse habitat. In 2005, San Miguel County amended its Land Use 
Codes to include consideration and implementation, to the extent 
possible, of conservation measures for the sage-grouse when considering 
land use activities and development located in Gunnison sage-grouse 
habitat (San Miguel County, unpubl. lit. 2005). In addition to the 
county protections, Gunnison County has 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 and RCP. San Miguel County has 
recently hired a Gunnison Sage-grouse Coordinator for the San Miguel 
Basin population. The efforts of these two counties reflect positively 
on their willingness to conserve Gunnison sage-grouse.
    Colorado State statute (C.R.S. 30-28-101) exempts parcels of land 
of 14 ha (35 ac) or more per home from regulation, so county zoning 
laws in Colorado can only restrict developments with housing densities 
greater than one house per 14 ha (35 ac). This situation allows some 
parcels to be exempt from county regulation and may negatively affect 
some sage-grouse. However, we have no data to indicate that this is 
threatening individual populations or individuals. We could find no 
data on the precise threshold of the number of acres per house that 
will affect Gunnison sage-grouse.
    Habitat loss is not regulated or monitored in Colorado counties 
where Gunnison sage-grouse occurs. Therefore, conversion of 
agricultural land from one use to another, such as native pasture 
containing sagebrush converted to another use, such as cropland, would 
not normally come before a county zoning commission.
    We recognize that 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 influence sage-grouse. 
However, we were unable to obtain information regarding the nature or 
extent of zoning

[[Page 19976]]

efforts and their direct or indirect effects on populations and 

State Laws and Regulations

    Colorado Revised Statutes, Title 33 Article 1 give CDOW 
responsibility for the management and conservation of wildlife 
resources within State borders. Title 33 Article 1-101, Legislative 
Declaration requires a continuous operation of planning, acquisition, 
and development of wildlife habitats and facilities for wildlife-
related opportunities. The CDOW is required by statute (C.R.S. 106-7-
104) to provide counties with information on ``significant wildlife 
habitat,'' and provide technical assistance in establishing guidelines 
for designating and administering such areas, if asked. The CDOW also 
has authority to regulate possession of the Gunnison sage-grouse, set 
hunting seasons, and issue citations for poaching. The Wildlife 
Resources Code of Utah (Title 23) provides UDWR the powers, duties, 
rights, and responsibilities to protect, propagate, manage, conserve, 
and distribute wildlife throughout the State. Section 23-13-3 declares 
that wildlife existing within the State, not held by private ownership 
and legally acquired, is property of the State. Sections 23-14-18 and 
23-14-19 authorize the Utah Wildlife Board to prescribe rules and 
regulations for the taking and/or possession of protected wildlife, 
including Gunnison sage-grouse.
    Gunnison sage-grouse are managed by CDOW 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. However, in 2000, CDOW 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. The Gunnison sage-grouse is listed as 
a species of special concern in Colorado and a sensitive species in 
Utah providing heightened priority for management (Gary Skiba, CDOW, 
pers. comm. 2006; Guy Wallace, UDWR pers. comm. 2006).
    Easements that prevent long-term or permanent habitat loss by 
prohibiting development are held by CDOW, UDWR, Natural Resources 
Conservation Service (NRCS), NPS, and non-governmental organizations 
(Table 3). Some of the easements include conservation measures that are 
specific for Gunnison sage-grouse, while most are directed at other 
species, such as big game (GSRSC 2005). We are aware that some of these 
easements do protect existing sage-grouse habitat. However, we do not 
have information on the location or size of the easements with sage-
grouse specific conservation measures and, therefore, cannot assess 
their overall value to Gunnison sage-grouse.

 Table 3.--Acres of Conservation Easements by Population and Percentages
         of Occupied Habitat Protected by Easements (GSRSC 2005)
                  Population                     Number of     habitat
                                                   acres      (percent)
Gunnison Basin................................       26,145            4
San Miguel Basin..............................          844            1
Monticello....................................        2,560            1
Pi[ntilde]on Mesa.............................        7,314           19
Crawford......................................          523            2

    The CDOW has been gathering information from landowners who may be 
interested in signing up under the CCAA referenced earlier in this 
document. As of January 2006, 72 landowners owning 41,278 ha (102,000 
ac) have expressed an interest in enrolling their lands under the CCAA.
    States regulate non-coal mining in the United States. Colorado law 
(State Statute Title 34, Article 32) contains language intended to 
protect wildlife resources through appropriate reclamation and 
encourages revegetation using native species. Utah mining regulations 
(R647-4-110) allow reclamation to wildlife resource use.
    We are not aware of any conservation measures implemented for 
potential oil and gas development impacts to Gunnison sage-grouse on 
private lands underlain with privately-owned minerals, which are 
regulated by the Colorado Oil and Gas Conservation Commission or the 
Utah Division of Oil, Gas, and Mining. 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 are not aware of any conservation 
measures established for Gunnison sage-grouse on State school section 
lands other than a request to withdraw or apply ``no surface 
occupancy'' and conservation measures from the RCP to four sections 
available for oil and gas leasing in the San Miguel Basin population 
(see Factor A for further discussion). State school section lands 
account for only 1 percent of occupied habitat in Colorado and 1 
percent in Utah so impacts may be considered negligible. The UDWR does 
not own any land within occupied habitat in Utah. The CDOW owns 2 
percent of the occupied habitat in Colorado, with some management for 
Gunnison sage-grouse on those lands.

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). 
Federal agencies are responsible for managing 55 percent of the total 
Gunnison sage-grouse habitat (GSRSC 2005). The Federal agencies with 
the most sagebrush habitat are BLM, an agency of the Department of the 
Interior, and USFS, an agency of the U.S. Department of Agriculture. 
The NPS in the Department of the Interior also has responsibility for 
lands that contain sage-grouse habitat.
    About 42 percent of occupied habitat is on BLM-administered land 
(GSRSC 2005). 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 and the Mineral Leasing Act (30 U.S.C. 181 et seq.) that address 
wildlife habitat protection on BLM-administered land include 43 CFR 
3162.3-1 and 43 CFR 3162.5-1; 43 CFR 4120 et seq.; 43 CFR 4180 et seq.
    Resource Management Plans (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 1601.0-5(k)).
    The RMPs provide a framework and programmatic guidance for activity 
plans, which are site-specific plans written to implement decisions 
made in a RMP. Examples include Allotment Management Plans that address 
livestock grazing, oil and gas field development, travel management, 
and wildlife habitat management. Activity plan decisions normally 
require additional planning and National Environmental Policy Act 
(NEPA) analysis. Within the Gunnison Basin population 56 percent of the 
BLM allotment acreage in occupied habitat

[[Page 19977]]

currently has Gunnison sage-grouse habitat objectives incorporated into 
the allotment management plans (BLM, unpubl. lit. 2005h). Rangewide, 
only 20 percent of BLM grazing allotments have thus far incorporated 
Gunnison sage-grouse conservation measures and/or habitat objectives 
into the allotment management plans or in permit renewals.
    On November 16, 2004, BLM Instruction Memorandum (IM) 2005-024 
transmitted information to all BLM field and Washington Office 
officials regarding the development of a National BLM Sage-grouse 
Habitat Conservation Strategy for BLM-administered lands. This strategy 
is described as the framework to address the conservation of sage-
grouse and risk to sagebrush habitats on lands and activities 
administered by BLM. It commits BLM to work with States and local 
interests on this issue. The IM instructed BLM State Directors to 
develop a process and schedule to update deficient RMPs to adequately 
address sage-grouse and sagebrush conservation needs. The BLM has 
developed a process to update RMPs in Colorado, and has notified the 
Service of general timeframes for RMP updates but specific deadlines 
have not been provided. The BLM continues to update applicable RMPs and 
activity plans.
    The BLM has regulatory authority for oil and gas leasing, 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 planning 
handbook has program-specific guidance for fluid minerals (which 
include oil and gas) that specifies that RMP decisions will identify 
restrictions on areas subject to leasing, including closures, as well 
as lease stipulations (BLM 2000). 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 2000). 
The BLM has regulatory authority to condition ``Application for Permit 
to Drill'' authorizations, conducted under a lease that does not 
contain sage-grouse conservation stipulations (BLM 2004). Also, oil and 
gas leases have a 200 m (650 ft) stipulation, which allows movement of 
the drilling area by that distance (BLM 2004). The BLM states that many 
of their field offices work with the operators to move a proposed 
drilling site farther or justify such a move through the site-specific 
NEPA process (BLM 2004).
    For existing oil and gas leases on BLM land in occupied Gunnison 
sage-grouse habitat, oil and gas companies can conduct drilling 
operations if they wish, but always subject to permit conditions. The 
BLM has stopped issuing new drilling leases in occupied sage-grouse 
habitat in Colorado at least until the new RMPs are in place. All 
occupied habitat acreages in the Crawford Area and Gunnison Basin 
populations are covered by this policy. However, leases already exist 
in 17 percent in the Pi[ntilde]on Mesa population, and 49 percent in 
the San Miguel Basin population.
    The oil and gas leasing regulations authorize BLM to modify or 
waive lease terms and stipulations if the authorized officer determines 
that the factors leading to inclusion of the term or stipulation have 
changed sufficiently to no longer justify protection, or if proposed 
operations would not cause unacceptable impacts (43 CFR 3101.1-4). The 
Service has no information indicating that the BLM has granted a 
significant number of waivers of stipulations pertaining to the 
Gunnison sage-grouse and/or their habitat.
    The Energy Policy and Conservation Act of 2000 included provisions 
requiring the Secretary of the Department of the Interior to conduct a 
scientific inventory of all onshore Federal lands to identify oil and 
gas resources underlying these lands and the nature and extent of any 
restrictions or impediments to the development of such resources 
(U.S.C. Title 42, Chapter 77, section 6217(a)). On May 18, 2001, the 
President signed Executive Order 13212--Actions to Expedite Energy-
Related Projects (66 FR 28357, May 22, 2001), which states that it is 
the Administration's policy that the executive departments and agencies 
shall take appropriate actions, to the extent consistent with 
applicable law, to expedite projects that will increase the production, 
transmission, or conservation of energy. The Executive Order specifies 
that this includes expediting review of permits or taking other actions 
as necessary to accelerate the completion of projects, while 
maintaining safety, public health, and environmental protections. The 
BLM has responded to these declarations with the issuance of several 
IMs to their staff that may influence sage-grouse conservation during 
these actions, including providing guidance for planning relative to 
oil and gas operations and focusing efforts for resource recovery in 
seven areas, two of which are within Gunnison sage-grouse habitats (IM 
2003-137, April 3, 2003; IM 2003-233, July 28, 2003; IM CO-2005-038, 
July 12, 2005).
    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)). The 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). The guidelines 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). The BLM is 
required to take appropriate action not 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 
agreed to work with their resource advisory councils 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 they apply to all BLM actions, not just 
livestock grazing (BLM Manual 180.06.A). Both Colorado and Utah have 
resource advisory councils. Since Gunnison sage-grouse habitats are a 
special status species, these standards will specifically address the 
habitat requirements of the Gunnison Sage Grouse and help to minimize 
any threats and improve existing habitats.
    On December 8, 2003, BLM issued a proposed rule (68 FR 68452) to 
modify the current grazing management regulation in two ways: (1) It 
provides that assessment and monitoring standards are needed to support 
a determination that livestock grazing significantly contributes to not 
meeting a standard or conforming with a guideline; and (2) it requires 
BLM to analyze, formulate and propose appropriate action within 24 
months of the determination rather than before the start of the next 
grazing year.
    In signing the RCP (GSRSC 2005), BLM has agreed to follow

[[Page 19978]]

recommendations for conservation efforts addressing the effects of 
grazing, oil and gas development and other threats, within the 
constraints of existing laws, policies, regulations, and management 
plans, and while considering the needs or implications to other species 
and multiple uses. It will take time for BLM to address the time 
requirement necessary to revise and formally incorporate Gunnison sage-
grouse conservation measures and habitat objectives in all of their 
RMPs through a rulemaking. In the meantime, the Colorado Office of the 
BLM issued IM CO-2005-038, which provides an interim policy to 
implement the RCP. The IM directs that the RCP guidance and strategies 
be applied through site-specific analysis consistent with NEPA for all 
projects or actions in Gunnison sage-grouse habitat. For surface 
disturbing activities such as oil and gas development the IM directs 
BLM staff to work with the operator to minimize habitat loss and 
fragmentation. Moreover, if the local conservation plans for each 
population have additional measures that address local conditions the 
IM directs BLM staff to consider if they are more effective than 
guidance in the RCP and, if so, to implement them. Full implementation 
of the RCP, according to the IM, will occur as guidance and strategies 
are considered and analyzed during RMP revisions and/or amendments. 
These actions will contribute to the conservation of the Gunnison Sage 
Grouse and help to minimize any potential threat from activities on 
Federal lands in the Gunnison's range.
    The USFS has management authority for 10 percent of the occupied 
Gunnison sage-grouse habitat (GSRSC 2005). Management of Federal 
activities on 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). 
This has historically been done through a NEPA process, including 
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 USFS planning process is 
similar to that of BLM.
    The 1982 NFMA implementing regulation for land and resource 
management planning (1982 rule, 36 CFR part 219), under which all 
existing forest plans were prepared, requires USFS to manage habitat to 
maintain viable populations of existing native vertebrate species on 
National Forest System lands (1982 rule, 36 CFR 219.19). A new USFS 
planning regulation was promulgated on January 5, 2005 (70 FR 1023). 
Under the new regulation a desired condition description and guidelines 
will be provided, rather than a set of prescriptive standards that 
apply to projects. Planning, and decisions for projects and activities, 
will address site-specific conditions and identify appropriate 
conservation measures to take for each project or activity.
    Under the new regulation, the purpose of forest plans is to 
establish goals and to set forth guidance to follow in pursuit of those 
goals. The rule calls for five components of plans: Desired conditions; 
objectives; guidelines; suitability of areas; and special areas (36 CFR 
219.7(a)(2)). The rule states that these components are intended to 
provide general guidance and goals or other information to be 
considered in subsequent project and activity decisions, and that none 
of these components are commitments or final decisions approving 
projects and activities (36 CFR 219.7(a)(2)). Approval of a plan, plan 
amendment, or plan revision comprised of these five components may be 
categorically excluded from NEPA documentation (36 CFR 219.4(b)).
    The new regulation requires plans to provide a framework to 
contribute to sustaining native ecological systems by providing 
ecological conditions to support diversity of native plants and animal 
species in the plan area (36 CFR 219.10 (b)). Ecosystem diversity is 
described as being the primary means by which a plan contributes to 
sustaining ecological systems (36 CFR 219.10 (b)), and USFS states that 
this focus is expected to conserve most species. The regulation defines 
species-of-concern as ``Species for which the Responsible Official 
determines that management actions may be necessary to prevent listing 
under the Endangered Species Act'' (36 CFR 219.16).
    For each unit of the National Forest System, the transition period 
for the new regulation is 3 years (36 CFR 219.14). A document approving 
a plan developed, revised, or amended using the new regulation must 
include a description of the effects of the plan on existing permits, 
contracts, or other instruments implementing approved projects and 
activities (36 CFR 219.8(a)).
    The Gunnison sage-grouse is designated as a USFS sensitive species 
in Region 2 (Colorado) and Region 4 (Utah), thereby ensuring and 
enhancing the management awareness of the species under the new 
planning rule. The forests within the range of sage-grouse provide 
important seasonal habitats for the species, particularly the Grand 
Mesa, Uncompahgre, and Gunnison National Forests. While the 1982 
planning regulation, including its provision for population viability, 
was used in the development of the existing Forest Plans, no 
information has been provided regarding specific implementation of the 
above new regulations and policies for the Gunnison sage-grouse. 
However, any agency action taken under the new planning rule will 
require consideration of Gunnison Sage Grouse habitat.
    We did not receive information from the USFS on whether habitat 
objectives and conservation measures have yet been incorporated into 
grazing allotments and whether local conservation plan sage-grouse 
habitat objectives and conservation measures have been incorporated 
into Forest Plans or LRMPs.
    To date USFS has not deferred or withdrawn oil and gas leasing in 
occupied habitat, but sage-grouse conservation measures can be included 
at the ``Application for Permit to Drill'' stage. The BLM, which 
regulates oil and gas leases on USFS lands, has the authority to defer 
leases. However, the only population with USFS lands that are in areas 
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).
    The NPS is responsible for managing 2 percent of occupied Gunnison 
sage-grouse habitat (GSRSC 2005). The NPS Organic Act (39 Stat. 535; 16 
U.S.C. 1, 2, 3, and 4) 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 Recreation Area include 
portions of occupied habitat of the Crawford and Gunnison Basin 
populations. Gunnison sage-grouse conservation measures are not 
included in the General Management Plan, but

[[Page 19979]]

are included in current RMPs. They also will be incorporated when the 
RMPs are revised or amended. The NPS is currently following 
conservation measures in the local conservation plans and the RCP 
(Myron Chase, NPS, pers. comm. 2005).
    The NRCS of the U.S. Department of Agriculture assists farmers, 
ranchers, and other private landowners in reducing threats to sage-
grouse habitat by providing technical assistance and financial 
resources to support management and habitat restoration efforts, 
helping farmers and ranchers maintain and improve habitat as part of 
larger management efforts, and developing technical information to 
assist NRCS field staff with sage-grouse considerations when working 
with private landowners. The NRCS has the Wildlife Habitat Incentive 
Program and Environmental Quality Incentive Program that can be used to 
fund projects implementing conservation measures in Gunnison sage-
grouse habitat. The Service's Partners for Fish and Wildlife Program 
also can fund conservation measures for Gunnison sage-grouse. All of 
these programs have contributed to Gunnison Sage Grouse conservation 
within its range by converting croplands to habitat improving habitat 
or restoring habitat.

Conclusion for Factor D

    Gunnison sage-grouse conservation has been addressed through 
numerous local, State, and Federal plans, laws, regulations, and 
policies. Current county regulations provide some ability to limit 
impacts to sage-grouse habitat from housing developments where the area 
is zoned for under 14 ha (35 ac) per house. Both counties where the 
largest populations of Gunnison sage-grouse occur have Land Use 
Resolutions or Codes to promote Gunnison sage-grouse conservation. The 
CDOW and UDWR have implemented and continue to pursue conservation 
easements in Colorado and Utah, respectively, to conserve Gunnison 
sage-grouse habitat and the species' needs. State wildlife regulations 
provide opportunities to address other conservation needs of the 
    Impacts resulting from current leases for oil and gas development 
on Federal lands are regulated at the ``Application for Permit to 
Drill'' stage as protective stipulations are applied through guidance 
in IM CO-2005-038. Grazing impacts are regulated with existing laws, 
regulations, and policies. Laws, regulations, and policies guiding 
development and implementation of land management plans for all the 
Federal agencies, address conservation of Gunnison sage-grouse habitat. 
In light of the fact that implementation of the aforementioned laws, 
regulations, and policies has not resulted in a decline within recent 
timeframes, as analyzed by Garton (2005) and, based on the best 
scientific and commercial data available we have concluded that 
inadequacy of existing regulatory mechanisms does not threaten or 
endanger the sage-grouse throughout all or a significant portion of its 
range in the foreseeable future.

E. Other Natural or Manmade Factors Affecting Its Continued Existence

    Other factors potentially affecting the Gunnison sage-grouse's 
continued existence include genetic risks, drought, recreational 
activities, and pesticides.


    Small populations face three primary genetic risks: Inbreeding 
depression; loss of genetic variation; and accumulation of new 
mutations. Inbreeding can have individual and population consequences 
by either increasing the phenotypic expression of recessive, 
deleterious alleles (Charlesworth and Charlesworth 1987) or by reducing 
the overall fitness of individuals in the population. Estimates for how 
large populations must be to prevent inbreeding depression vary 
dramatically. For example, Lande (1995b), Lynch et al. (1995), and 
Charlesworth et al. (1993) suggested that populations will need to have 
a genetic effective population size of 1,000, 100, and 12 individuals, 
respectively, to avoid accumulating deleterious mutations. However, if 
mutation accumulation is a threat to small populations, it is expected 
to take hundreds to thousands of generations to occur (GSRSC 2005).
    Oyler-McCance et al. (2005) investigated population structure of 
Gunnison sage-grouse using mitochondrial DNA sequence data from seven 
geographic areas (Cerro Summit-Cimarron-Sims Mesa, Crawford, Gunnison 
Basin, Curecanti area of the Gunnison Basin, Monticello-Dove Creek, 
Pi[ntilde]on Mesa, and San Miguel Basin). They found that levels of 
genetic diversity were highest in the Gunnison Basin, which 
consistently had more alleles and contained most of the alleles present 
in other populations. All other populations had much lower levels of 
diversity. These lower diversity levels are linked to small population 
sizes and a high degree of geographic isolation. Collectively, the 
smaller populations contain 24 percent of the genetic diversity of the 
species. Individually, each of the small populations may not be 
important genetically to the survival of the species, but collectively 
it is possible that 24 percent of the genetic diversity is important to 
future rangewide survival of the species. All populations sampled were 
found to be genetically discrete units (Oyler-McCance et al. 2005), so 
the loss of any of them would result in a decrease in genetic diversity 
of the species. In addition, multiple populations across a broad 
geographic area provide insurance against a single catastrophic event 
(such as 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).
    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. Oyler-McCance et al. (2001) 
documented a 20 percent loss and 37 percent fragmentation of sagebrush 
habitat in southwestern Colorado between the late 1950s and the early 
1990s, which led to the current isolation of these populations and is 
consistent with the documented low amounts of gene flow and isolation 
by distance (Oyler-McCance et al. 2005). However, Oyler-McCance et al. 
(2005) 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 San Miguel 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 suggests that the San Miguel 
population may act as a conduit of gene flow among the satellite 
populations surrounding the larger population in Gunnison. 
Additionally, Oyler-McCance et al. (2005) found that another potential 
disperser into Crawford was from the Gunnison Basin. This is not 
surprising given their close geographic proximity.
    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), suggestions range from 500-
5,000 individuals (Franklin 1980; Lande and Barrowclough 1987; Lande 
1995a). Similarly, population sizes in the upper 100s-1,000s are 
reported to be required for a higher probability of persistence over 
100 years (Shaffer 1987). While the persistence of wild populations is

[[Page 19980]]

usually influenced more by ecological rather than by genetic effects, 
once they are reduced in size, genetic factors become increasingly 
important (Lande 1995a).

Population Viability Analysis

    The CDOW contracted for a population viability analysis (PVA) for 
the Gunnison sage-grouse (Miller 2004). The PVA is a tool used to 
predict the probability of extinction for a wildlife population under 
various management scenarios. They are typically based on available 
population data which are often inadequate for a complete understanding 
of complex systems. Therefore, PVAs only provide an approximation of 
how a species may respond to various management alternatives without 
consideration of threats, since data are not available to determine how 
demographic rates will be affected by factors such as habitat loss or 
fragmentation. Also, since a PVA is a model, it does not present a 
complete picture of the system (GSRSC 2005 and references therein).
    The purpose of the Gunnison sage-grouse PVA was to assist the CDOW 
in evaluating the relative risk of extinction for each population under 
the current conditions (i.e. the risk of extinction if nothing changes) 
and 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). The results of this analysis 
indicated 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). In 
contrast, populations in excess of 500 birds had an extinction risk of 
less than 5 percent within the same time period. These results suggest 
that the Gunnison Basin population is likely to persist long term and, 
in the absence of intervention, the Cerro Summit-Cimarron-Sims Mesa and 
Poncha Pass populations and the Dove Creek group of the Monticello-Dove 
Creek population may be extirpated (GSRSC 2005). Loss of genetic 
diversity from the extirpation of the two populations and the group 
would not result in a substantial effect to the species as a whole, 
because their genetic composition is largely represented in the other 
populations. The remaining populations currently have estimated numbers 
between 150 and 350 birds, up from 125-250 in 2004, and their relative 
extinction risk as determined by the PVA is between those extremes.
    Garton's (2005) analysis of population trends also supports a 
relatively stable rangewide population, as well as a stable Gunnison 
Basin population for the last 10 years and longer. The RCP (GSRSC 2005) 
identified the need to increase gene flow among populations by 
improving corridors for between-population movement or translocation of 
selected genotypes from the Gunnison Basin to smaller populations, and 
vice-versa for population augmentation and maintenance of genetic 
    Oyler-McCance et al. (2005) conducted a genetic analysis of 
Gunnison sage-grouse populations using mitochondrial DNA sequence and 
nuclear microsatellite data. The Cerro Summit-Cimarron-Sims Mesa 
population was not included in this analysis due to inadequate sample 
sizes. The Poncha Pass population also was not included as it is 
composed of individuals transplanted from Gunnison Basin. In general, 
Gunnison sage-grouse have low levels of genetic diversity when compared 
to the greater sage-grouse (Oyler-McCance et al. 2005). Within the 
species, the Gunnison Basin birds had higher levels of genetic 
diversity than the other populations. Lower genetic diversity is 
consistent with small population size and geographical isolation 
(Oyler-McCance et al. 2005).
    In summary, although the Cerro Summit-Cimarron-Sims Mesa and Poncha 
Pass populations and the Dove Creek group of the Monticello-Dove Creek 
population may become extirpated in the near future, their genetic 
characteristics are largely represented in the remaining populations.


    Drought is a common occurrence throughout the range of the Gunnison 
sage-grouse (Braun 1998). Drought reduces vegetation cover (Milton et 
al. 1994; Connelly et al. 2004), 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. Approximately 2,544 sq km (982 sq mi) of sagebrush shrublands 
died in Utah in 2003 as a result of drought and infestations with the 
Aroga (webworm) moth (Connelly et al. 2004). Sage-grouse are affected 
by drought through the potential loss of vegetative habitat components 
and reduced insect production (Connelly and Braun 1997). 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; Schroeder et 
al. 1999).
    Greater sage-grouse populations declined during the 1930s period of 
drought (Patterson 1952; Willis et al. 1993; Braun 1998). 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). 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 
that reduce cover and food (Braun 1998).
    Drought began in the Gunnison Basin at least by 2001 and was most 
severe in 2002 (BLM, unpubl. lit. 2005i). The drought fully or 
partially killed approximately 40,470 ha (100,000 ac) (17 percent) of 
sagebrush in occupied range of the sage-grouse in the Gunnison Basin in 
2002 (BLM, unpubl. lit. 2005i). About 35,000 ha (86,000 ac) had 
significant dieback and 5,700 ha (14,000 ac) had moderate to light 
dieback of sagebrush and other shrubs. An estimated 4,000 ha (10,000 
ac) (2 percent) had substantial mortality of grasses and forbs. Phlox 
spp., a forb that is important sage-grouse forage in the spring and 
summer, had 50- to 80-percent mortality in areas where sagebrush 
dieback was over 50 percent (BLM, unpubl. lit. 2005i). In 2003, 48 
percent of all sagebrush plants were defoliated and 17 percent were 
dead (Wenger et al. 2003). By 2004, there was only modest recovery with 
increased moisture (BLM, unpubl. lit. 2005i). By 2005, sagebrush plants 
that were partially killed were recuperating (Sandy Borthwick, BLM, 
pers. comm. 2005).
    The drought also affected sagebrush communities in the San Miguel 
Basin population, particularly in the Dry Creek Basin area. During the 
late fall and winter of 2003-2004, CDOW conducted sagebrush transects 
in Dry Creek Basin to monitor drought-related impacts. Approximately 75 
percent of the sagebrush canopy in Dry Creek Basin was lost to 
sagebrush defoliation due to drought (Wenger et al. 2003). Although 
most plants survived and exhibited signs of recovery in 2003, large 
areas, particularly at low elevation, lost over 90 percent of the 
plants (Wenger et al. 2003). These communities started to recover in 
the spring of 2004, and plants that survived had heavy seed crops in 
the fall of 2004. Recuperation of these communities

[[Page 19981]]

continued in 2005 (Kathy Nickell, BLM, pers. comm. 2005). Detrimental 
effects on Gunnison sage-grouse, particularly on the birds attending 
the Desert Lek in Dry Creek Basin were observed after the drought. This 
lek had the greatest number of males counted (12-18) of the 3 leks in 
the population from 1996 through 2002, but was reduced to 0 in 2004 and 
2005 (CDOW, unpubl. lit. 2005b).
    In the Monticello group, most nesting areas are in poor condition 
due to lack of herbaceous cover as a result of drought and grazing 
(GSRSC 2005). Long-term drought also has reduced the availability of 
wet meadow habitat for brood-rearing (GSRSC 2005). Rains in 2005 have 
replenished some wet meadow habitats or riparian areas (Tammy Wallace, 
BLM, pers. comm. 2005). In the Pi[ntilde]on Mesa population the recent 
drought may have caused some limited, but unquantified, sagebrush and 
herbaceous understory die-back at lower elevations. Most plants 
affected do not appear to have died completely and sagebrush conditions 
have improved in 2004 and 2005 (CDOW, unpubl. lit. 2005g). Drought has 
been identified as a primary threat to the Crawford population 
(Crawford Area Conservation Plan 1998, GSRSC 2005). Drought conditions 
occurred there between 1999 and 2003 (Jim Ferguson, BLM, pers. comm. 
2005). No quantitative habitat data are available, but little grass, 
forb or sagebrush growth occurred during this period (Jim Ferguson, 
BLM, pers. comm. 2005). Since 1999, lek counts have declined. The BLM 
cut back on grazing animal unit months and there were no other 
identifiable negative impacts to BLM lands in the area during this 
timeframe, suggesting drought as the primary cause of decline (Jim 
Ferguson, BLM, pers. comm. 2005).
    The Gunnison sage-grouse is capable of enduring moderate or severe, 
but relatively short-term, drought as observed from persistence of the 
populations during drought conditions from 1999-2003 throughout much of 
the range. Habitat appeared to be negatively affected by drought across 
a broad area of the Gunnison sage-grouse's range. However, the 
reduction of sagebrush density in some areas, allowing for greater 
herbaceous growth, and stimulating the onset of sagebrush seed crops 
(Wenger et al. 2003) may actually be beneficial to sagebrush habitats 
over the long term. As a result, we find that Gunnison Sage Grouse is 
not sufficiently threatened by drought.


    Studies have determined that non-consumptive 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). 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 
    Recreation from off-highway vehicles, hikers, mountain bikes, 
campers, snowmobiles, bird watching, and other sources has affected 
many parts of the range, especially portions of the Gunnison Basin and 
Pi[ntilde]on Mesa population (BLM, unpubl. lit. 2005i; CDOW, unpubl. 
lit. 2005g). These activities can result in abandonment of lekking 
activities and nest sites, energy expenditure reducing survival, and 
greater exposure to predators (GSRSC 2005). Recreation is a significant 
land use on lands managed by BLM (Connelly et al. 2004) and 
recreational use of national forests has increased 76 percent since 
1977 (Rosenberg et al. 2004).
    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 come to recreate (BLM, unpubl. lit. 2005i). A 
comprehensive plan to manage motorized and non-motorized recreation is 
not available for BLM land in the Gunnison Basin, nor has there been 
monitoring or research on the extent of impacts (BLM, unpubl. lit. 
2005i). The BLM has seasonal closures on 17 roads with 6 of these 
closures protecting leks, but many more roads provide access to leks 
(BLM, unpubl. lit. 2005i). In addition, the Gunnison Field Office of 
BLM and Gunnison County collectively closed numerous roads to protect 
leks and nesting habitat within the Gunnison Basin for April and part 
of May 2006. While road closures may be violated, we have no data 
indicating that these violations are affecting the Gunnison Sage 
    Dispersed camping occurs at a low level on public lands in all of 
the populations, particularly during the hunting seasons for other 
species. A designated campground is located on BLM land near occupied 
habitat on Pi[ntilde]on Mesa (BLM, unpubl. lit. 2005a). No studies on 
recreational effects in the Pi[ntilde]on Mesa population have occurred. 
With its proximity to Grand Junction and expected growth in Mesa County 
and the Glade Park area, recreational impacts are expected to increase 
in the Pi[ntilde]on Mesa population area. However, we have no data 
indicating that these camping activities are adversely affecting 
Gunnison Sage Grouse.
    Domestic dogs accompanying recreationists can disturb, harass, 
displace, or kill Gunnison sage-grouse. Authors of many wildlife 
disturbance studies concluded that dogs with people, dogs on leash, or 
loose dogs provoked the most pronounced disturbance reactions from 
their study animals (Sime 1999 and references within). The primary 
consequences 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 behavior is affecting Gunnison Sage 


    Insects are an important component of sage-grouse chick and 
juvenile diets (Patterson 1952, Klebenow and Gray 1968, Johnson and 
Boyce 1990, Fischer et al. 1996a). Insects, especially ants 
(Hymenoptera) and beetles (Coleoptera), can comprise a major proportion 
of the diet of juvenile sage-grouse (Patterson 1952) and are important 
components of early brood-rearing habitats (Drut et al. 1994a). Most 
pesticide applications are not directed at control of ants and beetles. 
Pesticides 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. 
Infestations of Russian wheat aphids (Diuraphis noxia) have occurred in 
Gunnison sage-grouse occupied range in Colorado and Utah (GSRSC 2005). 
Disulfoton, a systemic organophosphate 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). 
One instance of greater sage-grouse mortality was reported following 
application of organophosphate and carbamate pesticides to cultivated 
crops in Idaho (Blus et al. 1989). More recently, an infestation of 
army cutworms (Euxoa auxiliaries) occurred in 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 by 
private landowners to control them (GSRSC 2005) but again, we have no 
data indicating any, adverse effects to Gunnison sage grouse.

[[Page 19982]]

    Use of insecticides to control mosquitoes is infrequent and 
probably do 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).

Conclusion for Factor E

    Although genetic consequences of low Gunnison sage-grouse 
population numbers could express themselves, there is no evidence that 
genetic factors have thus far caused a threat to the Gunnison sage-
grouse and it is unlikely that genetic factors (even without 
connectivity corridors or population augmentation) will be a threat for 
the foreseeable future. Effects of the severe drought centered on the 
year 2002 appear to have been ameliorated starting in 2004, and the 
sage-grouse survived the drought as they have survived other droughts 
in the past. Despite potentially greater effects to the smaller 
populations we have no evidence that drought is a threat to the 
survival of the Gunnison sage-grouse. Although disturbance and habitat 
destruction, fragmentation, or degradation may result from recreational 
activities, we have no data indicating that recreational impacts to 
Gunnison sage-grouse to demonstrate that recreation is or may become a 
threat to the species. Based on the available information, there 
appears to be infrequent use of insecticides in populations of the 
Gunnison sage-grouse and no data indicating there are direct adverse 
effects. The most likely impact of pesticides on Gunnison sage-grouse 
is the reduction of insect prey items. However, we could find no 
information to indicate that use of pesticides, in accordance with 
their label instructions, is a threat to Gunnison sage-grouse. Thus, 
based on the best scientific and commercial data available, we have 
concluded that other natural or manmade factors do not threaten or 
endanger the sage-grouse throughout all or a significant portion of its 
range in the foreseeable future.

Listing Determination

    We have assessed the best scientific and commercial information 
available and have determined that the Gunnison sage-grouse is not 
warranted for listing under the Endangered Species Act, as amended. We 
also no longer consider the species to be a candidate for listing. The 
2004 Candidate Notice of Review retained the listing priority number at 
a 2 based on perceived imminent threats of high magnitude. However, 
based on information obtained since our 2004 review (e.g., Garton 
2005), we have determined that threats to the Gunnison sage-grouse are 
neither imminent or of such magnitude that they threaten or endanger 
the existence of the species.
    The PVA (GSRSC 2005) concluded that the Cerro Summit-Cimarron-Sims 
Mesa and Poncha Pass populations and the Dove Creek group of the 
Monticello-Dove Creek population have a high probability of extirpation 
in the foreseeable future. However, these populations do not comprise a 
significant portion of the Gunnison sage-grouse range, as they are 
small and isolated. Even though these populations have higher 
probabilities of extirpation, we continue to strongly encourage CDOW 
and other interested parties to take necessary management actions to 
prevent their extirpation. For the remaining populations, numerous 
impacts pose potential threats to the Gunnison sage-grouse when 
considered under the listing factors. However, there is no evidence 
that the impacts are causing rangewide threats such that they are 
likely to cause the Gunnison sage-grouse to be in danger of extinction 
throughout all or a significant portion of its range in the foreseeable 
    If impacts to the species rise to the level of being a threat in 
the future or if the Service finds that the populations are declining 
significantly faster than they were found to have done in the past 
(Garton 2005), the Service will reexamine the listing status of the 
Gunnison sage-grouse. We will continue to monitor the status of the 
Gunnison sage-grouse and its habitat and will continue to accept 
additional information and comments from all governmental agencies, the 
scientific community, industry, or any other interested party 
concerning this finding.


    A complete list of references used in the preparation of this 
finding is available upon request from the Western Colorado Field 
Office (see ADDRESSES section).


    The authority for this action is the Endangered Species Act of 
1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: April 11, 2006.
H. Dale Hall,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 06-3619 Filed 4-17-06; 8:45 am]