[Federal Register Volume 77, Number 238 (Tuesday, December 11, 2012)]
[Proposed Rules]
[Pages 73827-73888]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-29331]
[[Page 73827]]
Vol. 77
Tuesday,
No. 238
December 11, 2012
Part IV
Department of the Interior
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Fish and Wildlife Service
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50 CFR Part 17
Endangered and Threatened Wildlife and Plants; Listing the Lesser
Prairie-Chicken as a Threatened Species; Proposed Rule
Federal Register / Vol. 77 , No. 238 / Tuesday, December 11, 2012 /
Proposed Rules
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R2-ES-2012-0071: 4500030113]
RIN 1018-AV21
Endangered and Threatened Wildlife and Plants; Listing the Lesser
Prairie-Chicken as a Threatened Species
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Proposed rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service, propose to list the
lesser prairie-chicken (Tympanuchus pallidicinctus), a grassland bird
known from southeastern Colorado, western Kansas, eastern New Mexico,
western Oklahoma, and the Texas Panhandle, as a threatened species
under the Endangered Species Act of 1973, as amended (Act). If we
finalize the rule as proposed, it would extend the Act's protection to
this species. We have determined that designation of critical habitat
for the lesser prairie-chicken under the Act is prudent but not
determinable at this time. We are seeking information and comments from
the public regarding the lesser prairie-chicken and this proposed rule.
DATES: We will accept comments received or postmarked on or before
March 11, 2013. Comments submitted electronically using the Federal
eRulemaking Portal (see ADDRESSES section, below) must be received by
11:59 p.m. Eastern Time on the closing date.
Public Hearings: We will hold four public hearings on this proposed
rule. The public hearings will be held in Woodward, Oklahoma, on
Tuesday, February 5; Garden City, Kansas, on Thursday, February 7;
Lubbock, Texas, on Monday, February 11; and Roswell, New Mexico, on
Tuesday, February 12. The public hearings will be held from 6:30 p.m.
to 8:30 p.m.
ADDRESSES: Document availability: You may obtain copies of the proposed
rule on the Internet at http://www.regulations.gov at Docket No. FWS-
R2-ES-2012-0071 or by mail from the Oklahoma Ecological Services Field
Office (see FOR FURTHER INFORMATION CONTACT).
Written Comments: You may submit written comments by one of the
following methods:
(1) Electronically: Go to the Federal eRulemaking Portal: http://www.regulations.gov. Search for Docket No. FWS-R2-ES-2012-0071. You may
submit a comment by clicking on ``Comment Now!''
(2) By hard copy: Submit by U.S. mail or hand-delivery to: Public
Comments Processing, Attn: FWS-R2-ES-2012-0071; Division of Policy and
Directives Management; U.S. Fish and Wildlife Service; 4401 N. Fairfax
Drive, MS 2042-PDM; Arlington, VA 22203.
We request that you send comments only by the methods described
above. We will post all comments on http://www.regulations.gov. This
generally means that we will post any personal information you provide
us (see the Information Requested section below for more information).
Public hearings: The public hearings will be held at the following
locations:
(1) Woodward, Oklahoma: High Plains Technology Center Seminar
Center, 3921 34th Street, Woodward, OK 73801.
(2) Garden City, Kansas: Garden City Community College, 801 N.
Campus Drive, Garden City, KS 67846.
(3) Lubbock, Texas: Lubbock Civic Center, 1501 Mac Davis Lane,
Lubbock, TX 79401.
(4) Roswell, New Mexico: Eastern New Mexico University Fine Arts
Auditorium, 64 University Boulevard, Roswell, NM 88203.
People needing reasonable accommodations in order to attend and
participate in the public hearing should contact Dixie Porter, Field
Supervisor, Oklahoma Ecological Services Field Office, as soon as
possible (see FOR FURTHER INFORMATION CONTACT below).
FOR FURTHER INFORMATION CONTACT: Dixie Porter, Field Supervisor,
Oklahoma Ecological Services Field Office, 9014 East 21st Street,
Tulsa, OK 74129; by telephone 918-581-7458 or by facsimile 918-581-
7467. Persons who use a telecommunications device for the deaf (TDD)
may call the Federal Information Relay Service (FIRS) at 800-877-8339.
SUPPLEMENTARY INFORMATION:
Executive Summary
This document consists of: (1) A proposed rule to list the lesser
prairie-chicken as a threatened species; and (2) a finding that
critical habitat is prudent but not determinable at this time.
Why we need to publish a rule. Under the Endangered Species Act, a
species may warrant protection through listing if it is an endangered
or threatened species throughout all or a significant portion of its
range. In this proposal, we are explaining why the lesser prairie-
chicken warrants protection under the Endangered Species Act. This rule
proposes to list the lesser prairie-chicken as a threatened species
throughout its range.
The Endangered Species Act provides the basis for our action. Under
the Endangered Species Act, we can determine that a species is an
endangered or threatened species based on any of five factors: (A) The
present or threatened destruction, modification, or curtailment of its
habitat or range; (B) overutilization for commercial, recreational,
scientific, or educational purposes; (C) disease or predation; (D) the
inadequacy of existing regulatory mechanisms; or (E) other natural or
manmade factors affecting its continued existence. The primary factors
supporting the proposed threatened status for lesser prairie-chicken
are the historical, ongoing, and probable future impacts of cumulative
habitat loss and fragmentation. These impacts are the result of:
conversion of grasslands to agricultural uses; encroachment by invasive
woody plants; wind energy development; petroleum production; and
presence of roads and manmade vertical structures including towers,
utility lines, fences, turbines, wells, and buildings.
We will request peer review of the methods used in our proposal. We
will specifically request that several knowledgeable individuals with
scientific expertise in this species or related fields review the
scientific information and methods that we used in developing this
proposal.
We are seeking public comment on this proposed rule. Anyone is
welcome to comment on our proposal or provide additional information on
the proposal that we can use in making a final determination on the
status of this species. Please submit your comments and materials
concerning this proposed rule by one of the methods listed in the
ADDRESSES section. Within 1 year following the publication of this
proposal, we will publish in the Federal Register a final determination
concerning the listing of the species or withdraw the proposal if new
information is provided that supports that decision.
Public Comments
We intend that any final action resulting from this proposed rule
will be based on the best scientific and commercial data available and
be as accurate and as effective as possible. Therefore, we request
comments or information from other concerned governmental agencies,
Native American tribes, the scientific community, industry, general
public, or any other interested parties concerning
[[Page 73829]]
this proposed rule. We particularly seek comments regarding:
(1) The historical and current status and distribution of the
lesser prairie-chicken, its biology and ecology, specific threats (or
lack thereof) and regulations that may be addressing those threats and
ongoing conservation measures for the species and its habitat.
(2) Information relevant to the factors that are the basis for
making a listing determination for a species under section 4(a) of the
Endangered Species Act of 1973, as amended (Act) (16 U.S.C. 1531 et
seq.), which are:
(a) The present or threatened destruction, modification, or
curtailment of the species' habitat or range;
(b) Overutilization for commercial, recreational, scientific, or
educational purposes;
(c) Disease or predation;
(d) The inadequacy of existing regulatory mechanisms; or
(e) Other natural or manmade factors affecting its continued
existence and threats to the species or its habitat.
(3) Which areas would be appropriate as critical habitat for the
species and why areas should or should not be proposed for designation
as critical habitat, including whether there are threats to the species
from human activity that would be expected to increase due to the
designation and whether that increase in threat would outweigh the
benefit of designation such that the designation of critical habitat
may not be prudent.
(4) Specific information on:
The amount and distribution of habitat for the lesser
prairie-chicken,
What may constitute ``physical or biological features
essential to the conservation of the species,'' within the geographical
range currently occupied by the species,
Where these features are currently found,
Whether any of these features may require special
management considerations or protection,
What areas, that were occupied at the time of listing (or
are currently occupied) and that contain features essential to the
conservation of the species, should be included in the designation and
why,
What areas not occupied at the time of listing are
essential for the conservation of the species and why.
(5) Information on the projected and reasonably likely impacts of
climate change on the lesser prairie-chicken and its habitat.
(6) Information as to which prohibitions, and exceptions to those
prohibitions, are necessary and advisable to provide for the
conservation of the lesser prairie-chicken pursuant to section 4(d) of
the Act.
Please note that submissions merely stating support for, or
opposition to, the action under consideration without providing
supporting information, although noted, will not be considered in
making a determination, as section 4(b)(1)(A) of the Act directs that
determinations as to whether any species is an endangered or threatened
species must be made ``solely on the basis of the best scientific and
commercial data available.''
You may submit your comments and materials concerning this proposed
rule by one of the methods listed in the ADDRESSES section.
If you submit a comment via http://www.regulations.gov, your entire
submission--including any personal identifying information--will be
posted on the Web site. If your submission is made via a hardcopy that
includes personal identifying information, you may request at the top
of your document that we withhold this information from public review.
However, we cannot guarantee that we will be able to do so. We will
post all hardcopy comments on http://www.regulations.gov. Please
include sufficient information with your comments to allow us to verify
any scientific or commercial information you include.
Comments and materials we receive, as well as supporting
documentation we used in preparing this proposed rule, will be
available for public inspection on http://www.regulations.gov at Docket
No. FWS-R2-ES-2012-0071, or by appointment during normal business hours
at the Oklahoma Ecological Services Field Office (see FOR FURTHER
INFORMATION CONTACT).
Previous Federal Actions
On October 6, 1995, we received a petition, dated October 5, 1995,
from the Biodiversity Legal Foundation, Boulder, Colorado, and Marie E.
Morrissey (petitioners). The petitioners requested that we list the
lesser prairie-chicken as threatened throughout its known historical
range in the United States. The petitioners defined the historical
range to encompass west-central Texas north through eastern New Mexico
and western Oklahoma to southeastern Colorado and western Kansas and
stated that there may have been small populations in northeastern
Colorado and northwestern Nebraska. The petitioners also requested that
critical habitat be designated as soon as the needs of the species are
sufficiently well known. However, from October 1995 through April 1996,
we were under a moratorium on listing actions as a result of Public Law
104-6, which, along with a series of continuing budget resolutions,
eliminated or severely reduced our listing budget through April 1996.
We were unable to act on the petition during that period. On July 8,
1997 (62 FR 36482), we announced our 90-day finding that the petition
presented substantial information indicating that the petitioned action
may be warranted. In that notice, we requested additional information
on the status, trend, distribution, and habitat requirements of the
species for use in conducting a status review. We requested that
information be submitted to us by September 8, 1997. In response to a
September 3, 1997, request by the Lesser Prairie-Chicken Interstate
Working Group, we reopened the comment period for an additional 30 days
beginning on November 3, 1997 (62 FR 59334). We subsequently published
our 12-month finding for the lesser prairie-chicken on June 9, 1998 (63
FR 31400), concluding that the petitioned action was warranted but
precluded by other higher priority listing actions.
On October 25, 1999, we published our combined plant and animal
candidate notice of review, which initially identified the lesser
prairie-chicken as a candidate for listing with a listing priority
number (LPN) of 8 (64 FR 57534). Our policy (48 FR 43098; September 21,
1983) requires the assignment of an LPN to all candidate species. This
listing priority system was developed to ensure that we have a rational
system for allocating limited resources in a way that ensures those
species in greatest need of protection are the first to receive such
protection. The listing priority system considers magnitude of threat,
immediacy of threat, and taxonomic distinctiveness in assigning species
numerical listing priorities on a scale from 1 to 12. In general, a
smaller LPN reflects a greater need for protection than a larger LPN.
The lesser prairie-chicken was assigned an LPN of 8 indicating that the
magnitude of threats was moderate and the immediacy of the threats to
the species was high.
On January 8, 2001 (66 FR 1295), we published our resubmitted
petition findings for 25 animal species, including the lesser prairie-
chicken, having outstanding ``warranted-but-precluded'' petition
findings as well as notice of one candidate removal. The lesser
prairie-chicken remained a candidate with an LPN of 8 in our October
30, 2001 (66 FR 54808); June 13, 2002 (67 FR 40657); May 4, 2004 (69
[[Page 73830]]
FR 24876); May 11, 2005 (70 FR 24870); September 12, 2006 (71 FR
53755); and December 6, 2007 (72 FR 69033) Candidate Notices of Review.
In our December 10, 2008 (73 FR 75176), candidate notice of review, we
changed the LPN for the lesser prairie-chicken from an 8 to a 2. This
change in LPN reflected a change in the magnitude of the threats from
moderate to high primarily due to an anticipated increase in the
development of wind energy and associated placement of transmission
lines throughout the estimated occupied range of the lesser prairie-
chicken. Our June 9, 1998, 12-month finding (63 FR 31400) did not
recognize wind energy and transmission line development as a threat
because such development within the known range was almost nonexistent
at that time. Changes in the magnitude of other threats, such as
conversion of certain Conservation Reserve Program (CRP) lands from
native grass cover to cropland or other less ecologically valuable
habitat and observed increases in oil and gas development, also were
important considerations in our decision to change the LPN. The
immediacy of the threats to the species did not change and continued to
be high. Our November 9, 2009 (74 FR 57804), November 10, 2010 (75 FR
69222), and October 26, 2011 (76 FR 66370) Candidate Notices of Review
retained an LPN of 2 for the lesser prairie-chicken.
Since making our 12-month finding, we have received several 60-day
notices of intent to sue from WildEarth Guardians (then Forest
Guardians) and several other parties for failure to make expeditious
progress toward listing of the lesser prairie-chicken. These notices
were dated August 13, 2001; July 23, 2003; November 23, 2004; and May
11, 2010. WildEarth Guardians subsequently filed suit on September 1,
2010, in the U.S. District Court for the District of Colorado. A
revised notice of intent to sue dated January 24, 2011, in response to
motions from New Mexico Oil and Gas Association, New Mexico Cattle
Growers Association, and Independent Petroleum Association of New
Mexico to intervene on behalf of the Secretary of Interior, also was
received from WildEarth Guardians.
This complaint was subsequently consolidated in the U.S. District
Court for the District of Columbia along with several other cases filed
by the Center for Biological Diversity or WildEarth Guardians relating
to petition finding deadlines and expeditious progress toward listing.
A settlement agreement in In re Endangered Species Act Section 4
Deadline Litigation, No. 10-377 (EGS), MDL Docket No. 2165 (D.D.C. May
10, 2011) was reached with WildEarth Guardians in which we agreed to
submit a proposed listing rule for the lesser prairie-chicken to the
Federal Register for publication by September 30, 2012.
Summary of Recent and Ongoing Conservation Actions
Numerous conservation actions have been implemented within the
historical range of the lesser prairie-chicken, many focused primarily
on the currently occupied portion of the range, during the last 10 to
15 years. The State conservation agencies have taken a lead role in
implementation of these actions, but several Federal agencies and
private conservation organizations have played an important supporting
role in many of these efforts. Recently, several multi-State efforts
have been initiated, and the following section briefly discusses many
of the known conservation efforts for the lesser prairie-chicken.
Multi-State Conservation Efforts
The CRP administered by the U.S. Department of Agriculture's (USDA)
Farm Services Agency and targeted at agricultural landowners has
provided short-term protection and enhancement of millions of acres
within the range of the lesser prairie-chicken. The CRP is a voluntary
program that allows eligible landowners to receive annual rental
payments and cost-share assistance to remove land from agricultural
production and establish vegetative cover for the term of the contract.
Contract terms are for 10 to 15 years, and the amount and dispersion of
land enrolled in CRP fluctuates as contracts expire and new lands are
enrolled. All five States within the range of the lesser prairie-
chicken have lands enrolled in CRP. Many of the States, with the
exception of Kansas, initially used nonnative grasses as the
predominant cover type established on enrolled lands. Kansas chose to
use native species of grasses as the cover type for many of their
enrolled lands, resulting in a considerable benefit to lesser prairie-
chicken conservation. As the program has evolved since its inception in
1985, use of native grasses as the predominant cover type has been
encouraged, resulting in even greater benefit for lesser prairie-
chickens. Use of native grasses in the CRP helps create suitable
nesting and brood rearing habitat for the lesser prairie-chicken.
The State Acres For Wildlife Enhancement program (SAFE) is a
conservation practice utilized under CRP to benefit high-priority
species including the lesser prairie-chicken. Beginning in 2008, the
SAFE program was implemented in Colorado, Kansas, New Mexico, Oklahoma,
and Texas to target grassland habitat improvement measures within the
range of the lesser prairie-chicken. These measures help improve
suitability of existing grasslands for nesting and brood rearing by
lesser prairie-chickens. In accordance with CRP guidelines, crop
producers can voluntarily enroll eligible lands in 10- to 15-year
contracts in exchange for payments, incentives, and cost-share
assistance to establish natural vegetation on enrolled lands. Areas
allocated for the SAFE program vary by State and are as follows:
Colorado 8,700 hectares (ha) (21,500 acres (ac)); Kansas 12,141 (30,000
ac); New Mexico 1,052 ha (2,600 ac); Oklahoma 6,111 ha (15,100 ac); and
Texas 31,727 (78,400 ac). Total potential enrollment in SAFE program is
59,731 ha (147,600 ac) or about 1 percent of the current estimated
occupied range. The current status of the SAFE program, organized by
State, is provided in the sections that follow.
In 2011, the USDA Natural Resources Conservation Service (NRCS)
began implementation of the Lesser Prairie Chicken Initiative. The
Lesser Prairie Chicken Initiative provides conservation assistance,
both technical and financial, to landowners throughout the Lesser
Prairie Chicken Initiative's administrative boundary. The NRCS has
partnered with other stakeholders to fund, through the Strategic
Watershed Action Teams program, additional staff positions dedicated to
providing accelerated and targeted technical assistance to landowners
within the current range of the lesser prairie-chicken. Technical
assistance is voluntary help provided by NRCS that is intended to
assist non-federal land users in addressing opportunities, concerns,
and problems related to the use of natural resources and to help land
users make sound natural resource management decisions on private,
tribal, and other non-federal land. This assistance may be in the form
of resource assessment, practice design, resource monitoring, or
follow-up of installed practices. The Lesser Prairie Chicken Initiative
focuses on maintenance and enhancement of suitable habitat while
benefiting agricultural producers by maintaining the farming and
ranching operations throughout the region. Numerous partners are
involved in this multi-state initiative including the State
conservation agencies, the Playa Lakes Joint Venture, and the Wood
Foundation. The Environmental Quality Incentives Program (EQIP) and the
Wildlife Habitat Incentives Program (WHIP) are the primary programs
used
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to provide for conservation through the Lesser Prairie Chicken
Initiative. The EQIP is a voluntary program that provides financial and
technical assistance to agricultural producers through contracts up to
a maximum term of 10 years in length. These contracts provide financial
assistance to help plan and implement conservation practices that
address natural resource concerns and opportunities to improve soil,
water, plant, animal, air, and related resources on agricultural land.
Similarly, the WHIP is a voluntary program designed for conservation-
minded landowners who want to develop and improve wildlife habitat on
agricultural land, including tribal lands. Through WHIP, NRCS may
provide both technical assistance and up to 75 percent cost-share
assistance to establish and improve fish and wildlife habitat. Cost-
share agreements between NRCS and the landowner may extend up to 10
years from the date the agreement is signed. Through these two
programs, NRCS has committed some $17.5 million to the Lesser Prairie
Chicken Initiative in Texas alone. In 2010, the identified funds were
allocated throughout the historical range, with some 33,956 ha (83,907
ac) placed under contract within those counties that intersected the
estimated occupied range. By entering into a contract with NRCS, the
landowner agrees to implement specified conservation actions through
provisions of the applicable Farm Bill conservation program, such as
WHIP or EQIP. Another 32,139 ha (79,417 ac) were allocated to contracts
on lands outside of the estimated occupied range but within unoccupied
portions of the historical range. In 2011, efforts were undertaken to
more precisely apply the funds to areas within the estimated occupied
range.
The North American Grouse Partnership, in cooperation with the
National Fish and Wildlife Foundation and multiple State conservation
agencies and private foundations, have embarked on the preparation of
the prairie grouse portions of an overarching North American Grouse
Management Strategy. The Prairie Grouse Conservation Plan, which was
completed in 2008 (Vodehnal and Haufler 2008, entire), provides
recovery actions and defines the levels of funding necessary to achieve
management goals for all species of prairie grouse in North America.
The prairie grouse portions of this strategy encompass some 26 million
ha (65 million ac) of grassland habitat in the United States and
Canada.
The Lesser Prairie-Chicken Interstate Working Group was formed in
1996. This group, composed largely of State agency biologists under the
oversight of the Western Association of Fish and Wildlife Agencies'
Grassland Coordinator, meets annually to share information on the
status of the lesser prairie-chicken, results of new research, and
ongoing threats to the species. The Working Group has played an
important role in defining and implementing conservation efforts for
the lesser prairie-chicken. In 1999, they published a conservation
strategy for the lesser prairie-chicken (Mote et al. 1999, entire).
Then, in 2008, the Working Group published a lesser prairie-chicken
conservation initiative (Davis et al. 2008, entire).
Since 2004, the Sutton Center has been working to reduce or
eliminate the mortality of lesser prairie-chickens due to fence
collisions on their study areas in Oklahoma and Texas. Forceful
collisions with fences during flight can cause direct mortality of
lesser prairie-chickens (Wolfe et al. 2007, pp. 96-97, 101). However,
mortality risk appears to be dependent on factors such as fencing
design (height, type, number of strands), length, and density, as well
as landscape topography and proximity of fences to habitats used by
lesser prairie-chickens. The Sutton Center has used competitive grants
and other funding sources to either physically remove unnecessary
fencing or to apply markers of their own design (Wolfe et al. 2009,
entire) to the top two strands to increase visibility of existing
fences. To date, approximately 335 kilometers (km) (208 miles (mi)) of
barbed-wire fence in Oklahoma and Texas have been treated. Treatments
are typically concentrated within 1.6 km (1 mi) of active lesser
prairie-chicken leks. Approximately 208 km (129 mi) of unneeded fences
have been removed. Collectively, these conservation activities have the
potential to significantly reduce the threat of collision mortality on
44,110 ha (109,000 ac) of occupied habitat. Our Partners for Fish and
Wildlife Program (PFW) initiated a similar fence marking effort in New
Mexico during 2008. Although the amount of marked fences has not been
quantified, the effort is an important contribution to ongoing
conservation efforts. However, continued fence construction throughout
the range of the lesser prairie-chicken and the localized influence of
these conservation efforts likely limits the effectiveness of such
measures at the population level.
The Service and the five State conservation agencies are currently
working with 19 wind energy development companies to develop a
programmatic Habitat Conservation Plan (HCP) for several species,
including the lesser prairie-chicken. An HCP is a planning document
required as part of an application for a permit for incidental take of
a Federally listed species. The HCP describes the anticipated effects
of the proposed taking; how those impacts will be minimized or
mitigated; and how the HCP is to be funded. The Oklahoma Department of
Wildlife Conservation (ODWC) received a nontraditional section 6 HCP
planning grant that is supporting this effort. The HCP is scheduled to
be finalized in the spring of 2014. We anticipate the conservation
program of the HCP could involve acquisition and setting aside of
conservation or mitigation lands.
Recently the five State conservation agencies developed an
Internet-based mapping tool as a pilot project under the Western
Governors' Association Wildlife Council. This tool, known as the
Southern Great Plains Crucial Habitat Assessment Tool (CHAT), was made
accessible to the public in September 2011. The CHAT is available for
use by conservation managers, industry, and the public to aid in
conservation planning for the lesser prairie-chicken. The tool
identifies priority habitat for the lesser prairie-chicken including
possible habitat corridors linking important conservation areas. The
CHAT classifies areas on a scale of 1 to 5 by their relative value as
lesser prairie-chicken habitat. The most important category is
identified as ``irreplaceable'' and is indicative of areas that are
rare or fragile and considered essential to achieving and maintaining
population viability. The lowest category is considered ``common'' and
represents areas that are relatively common and generally less limiting
to lesser prairie-chicken populations or metapopulations. These areas
are generally better suited for development uses. The CHAT includes
other data layers that may facilitate conservation planning, including
current and historical lesser prairie-chicken range, land cover types,
oil and gas well density, presence of vertical structures, and
hexagonal summary polygon to provide users contextual information about
the surrounding landscape. A revision of the CHAT is planned in the
coming months, and the tool will be updated annually. Use of the tool
is currently voluntary but ultimately may play an important role in
guiding future development and conserving important habitats.
Candidate Conservation Agreements (CCAs) and Candidate Conservation
Agreements with Assurances (CCAAs) are formal, voluntary agreements
[[Page 73832]]
between the Service and one or more parties to address the conservation
needs of one more candidate species or species likely to become
candidates in the near future. These agreements are intended to reduce
or remove identified threats to a species. Implementing conservation
efforts before species are listed increases the likelihood that
simpler, more cost-effective conservation options are available and
that conservation efforts will succeed. Development of CCAs and CCAAs
is guided by regulations at 50 CFR 17.22(d) and 50 CFR 17.32(d).
Under a CCA, Federal managers and other cooperators (non-
governmental organizations and lease holders) implement conservation
measures that reduce threats on Federal lands and leases. Under a CCAA,
non-Federal landowners and lease holders voluntarily provide habitat
protection or enhancement measures on their lands, thereby reducing
threats to the species. A section 10(a)(1)(A) Enhancement of Survival
Permit is issued in association with a CCAA. If the species is later
listed under the Act, the permit authorizes take that is incidental to
otherwise lawful activities specified in the agreement, when performed
in accordance with the terms of the agreement. Further, the CCAA
provides assurances that if the subject species is later listed under
the Act, participants who are appropriately implementing certain
conservation actions under the CCAA will not be required to implement
additional conservation measures.
The lesser prairie-chicken is covered by a CCA with the Bureau of
Land Management (BLM) and two ``umbrella'' CCAAs, one each in Texas and
New Mexico. A draft umbrella CCAA for Oklahoma was made available for
public review and comment on June 25, 2012 (77 FR 37917). An additional
CCAA has been established with a single landowner in southwestern
Kansas; however, this CCAA has since expired. Under these agreements,
the participants agree to implement certain conservation measures that
are anticipated to reduce threats to lesser prairie-chicken and improve
their population stability, through increases in adult and juvenile
survivorship, nest success, and recruitment rates and reduced
mortality. Dependent upon the level of participation, expansion of the
occupied range may occur. Conservation measures typically focus on
maintenance, enhancement, or restoration of nesting and brood rearing
habitat. Some possible conservation measures include removal of
invasive woody plants such as mesquite and eastern red cedar,
implementation of prescribed fire, marking of fences, removal of
unneeded fences, improved grazing management, and similar measures that
help reduce the impact of the existing threats.
All of the State conservation agencies and many Federal agencies
within the range of the lesser prairie-chicken conduct outreach efforts
intended to inform and educate the public about the conservation status
of the species. Many of these efforts specifically target landowners
and other interested stakeholders involved in lesser prairie-chicken
conservation. Annual festivals focused on the lesser prairie-chicken
are held in several States (Milnesand, New Mexico; Woodward, Oklahoma;
and Canadian, Texas) that help inform and raise awareness for the
public. Often festival participants are able to visit an active lesser
prairie-chicken breeding area to observe courtship displays.
Colorado
The Colorado Parks and Wildlife (CPW) hosted a workshop on the
conservation of the lesser prairie-chicken in late 2009. This workshop
provided information to local landowners and other interested parties
on conservation of the lesser prairie-chicken. Specific management
actions, such as grassland restoration and enhancement, intended to
benefit conservation of the lesser prairie-chicken were highlighted.
The NRCS is using EQIP and WHIP to implement habitat improvement
projects for the lesser prairie-chicken in Colorado. Colorado also has
implemented a Habitat Improvement Program (HIP) for the lesser prairie-
chicken that provides cost-sharing to private landowners, subject to
prior consultation and approval from a CPW biologist, for enrolling
fields or conducting habitat enhancements beneficial to the species.
Approximately 2,250 ha (5,560 ac) have been enrolled in this program
(Verquer and Smith 2011, p. 7). Additionally, Colorado has a Wildlife
Habitat Protection Program designed to facilitate acquisition of
conservation easements and purchase of lands for the lesser prairie-
chicken. The lesser prairie-chicken is one of five priorities for 2012,
and up to $14 million is available in the program.
Currently about 4,433 ha (10,954 ac) have been enrolled under the
lesser prairie-chicken CRP SAFE continuous sign-up in Colorado. These
enrolled areas are typically recently expired CRP lands and contain
older grass stands in less than optimal habitat condition. In late
winter 2010 or early spring 2011, one-third of these enrolled lands
received a forb and legume inter-seeding consisting of dryland alfalfa
and other species to improve habitat quality. This effort is
anticipated to result in the establishment of alfalfa and additional
forbs, resulting in improved nesting and brood-rearing habitat. Some
4,249 ha (10,500 ac) of the initial 8,701 ha (21,500 ac) allocated for
SAFE remain to be enrolled. High interest by landowners indicates that
these additional acres will be enrolled in the near future (Verquer and
Smith 2011, p. 7).
Our Partners for Fish and Wildlife Program (PFW) program has
contributed financial and technical assistance for restoration and
enhancement activities benefitting the lesser prairie-chicken in
Colorado. The PFW program has executed 14 private lands agreements
facilitating habitat restoration and enhancement for the lesser
prairie-chicken on about 9,307 ha (23,000 ac) of private lands in
southeastern Colorado.
A cooperative project between the CPW and the U.S. Forest Service
(USFS) has established several temporary grazing exclosures adjacent to
active leks on the Comanche National Grassland in an attempt to improve
nesting habitat. The efficacy of these treatments is unknown, and
further monitoring is planned to determine the outcome of these efforts
(Verquer and Smith 2011, p. 7).
In addition, more than 4,450 ha (11,000 ac) have been protected by
perpetual conservation easements held by CPW, The Nature Conservancy,
and the Greenlands Reserve Land Trust.
Kansas
The Kansas Department of Wildlife, Parks, and Tourism (KDWPT) has
targeted lesser prairie-chicken habitat improvements through various
means including the Landowner Incentive Program, voluntary mitigation
projects for energy development, and a state-level WHIP. The Landowner
Incentive Program improved some 9,118 ha (22,531 ac) for lesser
prairie-chickens during the period from 2007 to 2011. Since 2008, the
KDWPT has provided $64,836 in landowner cost-share through the WHIP for
practices benefitting the lesser prairie-chicken on about 2,364 ha
(5,844 ac). Currently more than 11,662 ha (28,819 ac) of the original
allocation have been enrolled under the lesser prairie-chicken CRP SAFE
continuous signup in Kansas. Primary practices include tree removal,
prescribed fire, grazing management (including perimeter fencing), and
native grass establishment that will improve lesser prairie-chicken
nesting and brood rearing habitat.
[[Page 73833]]
Funds available through the state wildlife grants program also have
been used to benefit the lesser prairie-chicken in Kansas. The KDWPT
was awarded a 5-year state wildlife grant in 2009 focusing on lesser
prairie-chicken habitat improvements. During the first funding cycle, a
total of $181,127.34 was allocated to six projects encompassing some
1,484 ha (3,667 ac). During two subsequent application periods, nine
more projects were funded at a cost of $180,584, targeting some 1,319
ha (3,260 ac).
Like several of the other States within the range of the lesser
prairie-chicken, the KDWPT partnered with Pheasants Forever and NRCS to
fund three employee positions that will provide technical assistance to
private landowners participating in conservation programs with an
emphasis on practices favorable to the lesser prairie-chicken. These
employees will primarily assist in the implementation and delivery of
the NRCS's Lesser Prairie Chicken Initiative in Kansas.
Additionally, KDWPT has a walk-in hunting program that was
initiated in 1995 in an effort to enhance the hunting tradition in
Kansas. The program provides hunters access to private property and has
become one of the most successful access programs in the country. By
2004, more than 404,000 ha (1 million ac) have been enrolled in the
program. Landowners receive a small payment in exchange for allowing
public hunting access to enrolled lands. Payments vary by the amount of
acres enrolled and length of contract period. Conservation officers
monitor the areas, and violators are ticketed or arrested for offenses
such as vandalism, littering, or failing to comply with hunting or
fishing regulations.
The Service's PFW program has contributed financial and technical
assistance for restoration and enhancement activities that benefit the
lesser prairie-chicken in Kansas. Primary activities include control of
invasive woody plant species like eastern red cedar and enhanced use of
prescribed fire to improve habitat conditions in native grasslands. The
PFW program has executed 54 private lands agreements on about 51,246 ha
(126,878 ac) of private lands benefitting conservation of the lesser
prairie-chicken in Kansas. An approved CCAA was developed on 1,133 ha
(2,800 ac) in south-central Kansas; however, this CCAA has since
expired.
New Mexico
In January 2003, a working group composed of local, state, and
Federal officials, along with private and commercial stakeholders, was
formed to address conservation and management activities for the lesser
prairie-chicken and dunes sagebrush lizard (Sceloporus arenicolus) in
New Mexico. This working group, formally named the New Mexico Lesser
Prairie-Chicken/Sand Dune Lizard Working Group, published the
Collaborative Conservation Strategies for the Lesser Prairie-Chicken
and Sand Dune Lizard in New Mexico (Strategy) in August 2005. This
Strategy provided guidance in the development of BLM's Special Status
Species Resource Management Plan Amendment (RMPA), approved in April
2008, which also addressed the concerns and future management of lesser
prairie-chicken and dunes sagebrush lizard habitats on BLM lands, and
established the Lesser Prairie-Chicken Habitat Preservation Area of
Critical Environmental Concern. Both the Strategy and the RMPA
prescribe active cooperation among all stakeholders to reduce or
eliminate threats to these species in New Mexico. As an outcome, the
land-use prescriptions contained in the RMPA now serve as baseline
mitigation (for both species) to those operating on Federal lands or
non-Federal lands with Federal minerals.
Following approval of the RMPA, a CCA was drafted by a team
including the Service, BLM, Center of Excellence for Hazardous
Materials Management, and participating cooperators. The CCA addresses
the conservation needs of the lesser prairie-chicken and dunes
sagebrush lizard on BLM lands in New Mexico by undertaking habitat
restoration and enhancement activities and minimizing habitat
degradation. These efforts would protect and enhance existing
populations and habitats, restore degraded habitat, create new habitat,
augment existing populations of lesser prairie-chickens, restore
populations, fund research studies, or undertake other activities on
their Federal leases or allotments that improve the status of the
lesser prairie-chicken. Through this CCA, Center of Excellence for
Hazardous Materials Management will work with participating cooperators
who voluntarily commit to implementing or funding specific conservation
actions, such as burying powerlines, controlling mesquite, minimizing
surface disturbances, marking fences, and improving grazing management,
in an effort to reduce or eliminate threats to both species. The CCA
builds upon the BLM's RMPA for southeast New Mexico. The RMPA
established the foundational requirements that will be applied to all
future Federal activities, regardless of whether a permittee or lessee
participates in this CCA. The strength of the CCA comes from the
implementation of additional conservation measures that are additive,
or above and beyond those foundational requirements established in the
RMPA. In addition to the CCA, a CCAA has been developed in association
with the CCA to facilitate conservation actions for the lesser prairie-
chicken and dunes sagebrush lizard on private and State lands in
southeastern New Mexico.
Since the CCA and CCAA were finalized in December 2008, 29 oil and
gas companies have enrolled a total of 330,180 ha (815,890 ac) of
mineral holdings under the CCA. In addition, 39 private landowners in
New Mexico have enrolled about 616,571 ha (1,523,573 ac). There
currently are additional pending mineral and ranching enrollment
applications being reviewed and processed for inclusion. Recently, BLM
also has closed 149,910 ha (370,435 ac) to future oil and gas leasing
and closed some 342,770 ha (847,000 ac) to wind and solar development.
They have reclaimed 536 ha (1,325 ac) of abandoned well pads and
associated roads and now require burial of powerlines within 3.2 km (2
mi) of leks. Some 52 km (32.5 mi) of aboveground powerlines have been
removed to date. Additionally, BLM has implemented control efforts for
mesquite (Prosopis glandulosa) on some 148,257 ha (366,350 ac) and has
plans to do so on an additional 128,375 ha (317,220 ac). More
discussion of mequite control is addressed in the ``Shrub Control and
Eradication'' section below.
Acquisition of land for the protection of lesser prairie-chicken
habitat also has occurred in New Mexico. The New Mexico Department of
Game and Fish (NMDGF) currently has designated 29 areas specifically
for management of the lesser prairie-chickens totaling more than 11,850
ha (29,282 ac). These areas are closed to the public during the
breeding and nesting season (March 1 to July 30), each year and
restrictions are in place to minimize noise and other activities
associated with oil and gas drilling. In 2007, the State Game
Commission used New Mexico State Land Conservation Appropriation
funding to acquire 2,137 ha (5,285 ac) of private ranchland in
Roosevelt County. This property, the Sandhills Prairie Conservation
Area (formerly the Lewis Ranch), is located east of Milnesand, New
Mexico, and adjoins two existing Commission-owned Prairie-Chicken
Areas. The BLM, on March 3, 2010, also acquired 3,010 ha (7,440 ac) of
land east of Roswell, New Mexico, to protect key
[[Page 73834]]
habitat for the lesser prairie-chicken. The Nature Conservancy owns and
manages the 11,331-ha (28,000-ac) Milnesand Prairie Preserve near
Milnesand, New Mexico.
The Service's PFW program also has been active in lesser prairie-
chicken conservation efforts in the State of New Mexico. Private lands
agreements have been executed on 65 properties encompassing some 28,492
ha (70,404 ac) of lesser prairie-chicken habitat in New Mexico.
Additionally the entire 3,683 ha (2,600 ac) allotted to the lesser
prairie-chicken CRP SAFE continuous signup in New Mexico has been
enrolled in the program.
Oklahoma
The ODWC partnered with the Service, the Oklahoma Secretary of
Environment, The Nature Conservancy, the Sutton Center, and the Playa
Lakes Joint Venture to develop the Oklahoma Lesser Prairie-Chicken
Spatial Planning Tool in 2009. The goal of the Oklahoma Lesser Prairie-
Chicken Spatial Planning Tool is to reduce the impacts of ongoing and
planned development actions within the range of the lesser prairie-
chicken by guiding development away from sensitive habitats used by the
species. The Oklahoma Lesser Prairie-Chicken Spatial Planning Tool
assigns a relative value rank to geographic areas to indicate the value
of the area to the conservation of the lesser prairie-chicken. The
higher the rank (on a scale of 1 to 8), the more important the area is
to the lesser prairie-chicken. The Oklahoma Lesser Prairie-Chicken
Spatial Planning Tool, therefore, can be used to identify areas that
provide high-quality habitat and determine where development, such as
wind power, would have the least impact to the species. The Oklahoma
Lesser Prairie-Chicken Spatial Planning Tool also can be used to
determine a voluntary offset payment based on the cost of mitigating
the impact of the anticipated development through habitat replacement.
The voluntary offset payment is intended to be used to offset the
impacts associated with habitat loss. Use of the Oklahoma Lesser
Prairie-Chicken Spatial Planning Tool and the voluntary offset payment
is voluntary.
To date, in excess of $11.1 million has been committed to the ODWC
through the voluntary offset payment program. Most recently, the ODWC
entered into a Memorandum of Agreement with Chermac Energy Corporation
to partially offset potential habitat loss from a planned 88.5-km (55-
mi) high-voltage transmission line. The line would run from near the
Kansas State line to the Oklahoma Gas and Electric Woodward Extra High
Voltage substation and will be used to carry up to 900 megawatts of
wind energy from an existing wind farm in Harper County. The Memorandum
of Agreement facilitates voluntary offset payments for impacts to the
lesser prairie-chicken and their habitat. The agreement calls for the
payment of a total of $2.5 million, with the money being used to help
leverage additional matching funds from private and Federal entities
for preservation, enhancement, and acquisition of lesser prairie-
chicken habitat. A large percentage of the voluntary offset payment
funds have been used to acquire lands for the conservation of the
lesser prairie-chicken and other fish and wildlife resources.
In 2008, the ODWC acquired two properties known to be used by the
lesser prairie-chicken. The Cimarron Bluff Wildlife Management Area
encompasses 1,388 ha (3,430 ac) in northeastern Harper County,
Oklahoma. The Cimarron Hills Wildlife Management Area in northwestern
Woods County, Oklahoma, encompasses 1,526 ha (3,770 ac). The ODWC also
recently purchased 5,580 ha (13,789 ac) within the range of the lesser
prairie-chicken to expand both the Beaver River and Packsaddle Wildlife
Management Areas in Beaver and Ellis Counties, respectively.
Oklahoma State University hosts prescribed fire field days to help
inform landowners about the benefits of prescribed fire for controlling
invasion of woody vegetation in prairies and improving habitat
conditions for wildlife in grassland ecosystems. Prescribed burning is
an important tool landowners can use to improve the value of CRP fields
and native prairie for wildlife, including the lesser prairie-chicken,
by maintaining and improving vegetative structure, productivity, and
diversity and by controlling exotic plant species. In 2009, the
Environmental Defense Fund partnered with Oklahoma State University to
prepare a report on the management of CRP fields for lesser prairie-
chicken management. The document (Hickman and Elmore 2009, entire) was
designed to provide a decision tree that would assist agencies and
landowners with mid-contract management of CRP fields.
Like the other States, ODWC has partnered in the implemention of a
State WHIP designed to enhance, create, and manage habitat for all
wildlife species, including the lesser prairie-chicken. The State WHIP
recently has targeted money for lesser prairie-chicken habitat
improvements.
Several different ``Ranch Conversations'' have been held in
northwestern Oklahoma over the past 10 years, most recently hosted by
the Oklahoma High Plains Resource Development and Conservation Office.
These meetings invited private landowners and the general public to
discuss lesser prairie-chicken conservation and management, receive
information, and provide input on programs and incentives that are
available for managing the lesser prairie-chicken on privately owned
habitats.
In an effort to address ongoing development of oil and gas
resources, the Oklahoma Wildlife Conservation Commission voted to
approve a Memorandum of Understanding with the Oklahoma Independent
Petroleum Association in February 2012 to establish a collaborative
working relationship for lesser prairie-chicken conservation. Through
this Memorandum of Understanding, the ODWC and Oklahoma Independent
Petroleum Association will identify and develop voluntary steps (Best
Management Practices) that can be taken by the Oklahoma Independent
Petroleum Association's members to avoid and minimize the impacts of
their operations on the lesser prairie-chicken. These Best Management
Practices are currently under development.
Oklahoma received a USDA Conservation Innovation Grant to develop a
wildlife credits trading program. When completed, the credit trading
program will provide incentives to landowners who manage their lands
for conservation of the lesser prairie-chicken. Currently, about 2,819
ha (6,965 ac) have been enrolled under the lesser prairie-chicken CRP
SAFE continuous signup in Beaver, Beckham, Ellis, and Harper Counties.
The ODWC, in early 2012, entered into a contract with Ecosystem
Management Research Institute to develop a conservation plan for the
lesser prairie-chicken in Oklahoma. The primary goal of the Oklahoma
Lesser Prairie Chicken Conservation Plan is to develop an overall
strategy for conservation of the lesser prairie-chicken in Oklahoma.
Development of the Oklahoma Lesser Prairie Chicken Conservation Plan
will involve synthesis of all pertinent information currently available
and input from diverse stakeholders. The Oklahoma Lesser Prairie
Chicken Conservation Plan will identify priority conservation areas,
population goals, and conservation strategies and actions; it also will
link conservation actions to appropriate entities and contain an
implementation timeline. A draft document is currently available,
public comments were solicited through
[[Page 73835]]
August 30, 2012, and the final plan is anticipated in September of
2012.
As discussed above, the ODWC has applied for an enhancement of
survival permit pursuant to section 10(a)(1)(A) of the Act that
includes a draft umbrella CCAA between the Service and ODWC for the
lesser prairie-chicken in 14 Oklahoma counties (77 FR 37917). The draft
CCAA and associated draft environmental assessment was made available
for public review and comment in June 2012. The Service and ODWC are
currently reviewing and addressing public comments, and a permitting
decision is anticipated in the near future
The Service's PFW program also has contributed financial and
technical assistance for restoration and enhancement activities that
benefit the lesser prairie-chicken in Oklahoma. Important measures
include control of eastern red cedar and fence marking and removal to
minimize collision mortality. The Oklahoma PFW program has implemented
154 private lands agreements on about 38,954 ha (96,258 ac) of private
lands for the benefit of the lesser prairie-chicken in the State.
Texas
The Texas Parks and Wildlife Department (TPWD) hosted a series of
landowner meetings and listening sessions in 6 (Hemphill, Wheeler,
Gray, Bailey, Cochran, and Gaines) of the 13 counties confirmed to be
occupied by the lesser prairie-chicken in Texas. Private landowners and
the general public were invited to discuss conservation and management,
receive information, and provide input on programs and incentives that
are available for managing the lesser prairie-chicken on privately
owned lands. In response to these meetings, TPWD worked with the
Service and landowners to finalize the first statewide umbrella CCAA
for the lesser prairie-chicken in Texas. The conservation goal of the
Texas CCAA is to encourage protection and improvement of suitable
lesser prairie-chicken habitat on non-Federal lands by offering private
landowners incentives to implement voluntary conservation measures
through available funding mechanisms and by providing technical
assistance and regulatory assurances concerning land use restrictions
that might otherwise apply should the lesser prairie-chicken become
listed. The conservation measures would generally consist of prescribed
grazing; prescribed burning; brush management; cropland and residue
management; range seeding and enrollment in various Farm Bill programs
such as the CRP, the Grassland Reserve Program, and SAFE program; and
wildlife habitat treatments through the EQIP. The Texas CCAA covers 50
counties, largely encompassing the Texas panhandle region, and was
finalized on May 14, 2009. Currently, 22 private landowners (totaling
approximately 255,044 ac) are enrolled under this agreement.
More recently, the TPWD, along with other partners, held five
meetings in the Texas panhandle region as part of an effort to promote
lesser prairie-chicken conservation. These meetings were held in May of
2009 and were intended to inform landowners about financial incentives
and other resources available to improve habitat for the lesser
prairie-chicken, including the SAFE program. The objective of the Texas
SAFE program, administered by the Farm Service Agency, is to restore
2,093 ha (20,000 ac) of native mixed-grassland habitat for the lesser
prairie-chicken in Texas. Additional allocations were approved, and
currently some 31,245 ha (77,209 ac) have been enrolled in the SAFE
program. Then, in March 2010, TPWD staff conducted a 2-day upland bird
workshop where lesser prairie-chicken research and management was
discussed.
In 2010, the NRCS and TPWD partnered to create an EQIP focused on
lesser prairie-chicken conservation. This program provides technical
and financial assistance to landowners interested in implementing land
management practices for the lesser prairie-chicken within its
historical range.
The Service's PFW program and the TPWD have been actively
collaborating on range management programs designed to provide cost-
sharing for implementation of habitat improvements for lesser prairie-
chickens. The Service provided funding to TPWD to support a Landscape
Conservation Coordinator position for the Panhandle and Southern High
Plains region, as well as funding to support Landowner Incentive
Program projects targeting lesser prairie-chicken habitat improvements
(brush control and grazing management) in this region. More than
$200,000 of Service funds were committed in 2010, and an additional
$100,000 was committed in 2011. Since 2008, Texas has addressed lesser
prairie-chicken conservation on some 5,693 ha (14,068 ac) under the
Landowner Incentive Program. Typical conservation measures include
native plant restoration, control of exotic vegetation, prescribed
burning, selective brush management, and prescribed grazing. Currently,
the PFW program has executed 66 private lands agreements on about
53,091 ha (131,190 ac) of privately owned lands for the benefit of the
lesser prairie-chicken in Texas.
The TPWD continues to establish working relationships with wind
developers and provides review and comment on proposed developments
whenever requested. Through this voluntary comment process, TPWD
provides guidance on how to prevent, minimize, and mitigate impacts
from wind and transmission development on lesser prairie-chicken
habitat and populations.
A Lesser Prairie-Chicken Advisory Committee also has been
established in Texas and functions to provide input and information to
the State's Interagency Task Force on Economic Growth and Endangered
Species. The purpose of the task force is to provide policy and
technical assistance regarding compliance with endangered species laws
and regulations to local and regional governmental entities and their
communities engaged in economic development activities so that
compliance with endangered species laws and regulations is as effective
and cost efficient as possible. Input provided by the Lesser Prairie-
Chicken Advisory Committee serves to help the Task Force prevent
listing and minimize harm to economic sectors if listing does occur.
The advisory committee also assists in outreach and education efforts
on potential listing decisions and methods to minimize the impact of
listing.
The TPWD has worked in conjunction with several Texas universities
to fund several lesser prairie-chicken research projects. In one of
those projects, TPWD evaluated the use of aerial line transects and
forward-looking infrared technology to survey for lesser prairie-
chickens. Other ongoing research includes evaluation of lesser prairie-
chicken population response to management of shinnery oak and
evaluation of relationships among the lesser prairie-chicken, avian
predators, and oil and gas infrastructure.
In 2009, the U.S. Department of Energy awarded Texas Tech
University and the TPWD a collaborative grant to conduct aerial surveys
on approximately 75 percent of the estimated currently occupied range.
This project aided in the initial development of a standardized
protocol for conducting aerial surveys for the lesser prairie-chicken
across the entire range. All five States are currently participating in
these surveys; and a complete analysis of the results is expected
sometime in the summer of 2012 and will be incorporated in the final
determination.
[[Page 73836]]
Recently, The Nature Conservancy of Texas acquired approximately
2,428 ha (6,000 ac) of private ranchland in Yoakum and Terry Counties
for the purpose of protecting and restoring lesser prairie-chicken
habitat. This acquisition helped secure a geographically important
lesser prairie-chicken population.
In addition to participation in annual lesser prairie-chicken
festivals, the TPWD published an article on the lesser prairie-chicken
and wind development in Texas in their agency magazine in October of
2009. The TPWD and the Dorothy Marcille Wood Foundation also produced a
12-page color brochure in 2009 about the lesser prairie-chicken
entitled ``A Shared Future.''
In summary, we recognize the importance of the conservation efforts
undertaken by all entities across the range of the lesser prairie-
chicken. These actions outlined above have, at least in some instances,
slowed, but not halted, alteration of lesser prairie-chicken habitat.
However, continued implementation of these and similar future actions
is crucial to lesser prairie-chicken conservation. In many instances,
these efforts have helped reduce the severity of the threats to the
species, particularly in localized areas. However, our review of
conservation efforts indicates that the measures identified are not
adequate to fully address the known threats, including the primary
threat of habitat fragmentation, in a manner that effectively reduces
or eliminates the threats (see discussion below). All of the efforts
are limited in size or duration, and the measures typically are not
implemented at a scale that would be necessary to effectively reduce
the threats to this species across its known range. Often the measures
are voluntary, with little certainty that the measures will be
implemented. In some instances, mitigation for existing development
within the range of the lesser prairie-chicken has been secured, but
the effectiveness of the mitigation is unknown. Conservation of this
species will require persistent, targeted implementation of appropriate
actions over the range of the species to sufficiently reduce or
eliminate the primary threats to the lesser prairie-chicken.
Available Conservation Measures
Conservation measures provided to species listed as endangered or
threatened under the Act include recognition, recovery actions,
requirements for Federal protection, and prohibitions against certain
practices. Recognition often results in public awareness and
facilitates conservation by Federal, State, Tribal, and local agencies;
private organizations; and individuals. The Act encourages cooperation
with the States and requires that recovery actions be carried out for
all listed species. The protection required by Federal agencies and the
prohibitions against certain activities involving listed species are
discussed, in part, below.
Recovery Planning
The primary purpose of the Act is the conservation of endangered
and threatened species and the ecosystems upon which they depend. The
ultimate goal of such conservation efforts is the recovery of these
listed species, so that they no longer need the protective measures of
the Act. Subsection 4(f) of the Act requires the Service to develop and
implement recovery plans for the conservation of endangered and
threatened species. The recovery planning process involves the
identification of actions that are necessary to halt or reverse the
species' decline by addressing the threats to its survival and
recovery. The goal of this process is to restore listed species to a
point where they are secure, self-sustaining, and functioning
components of their ecosystems.
Recovery planning includes the development of a recovery outline
soon after a species is listed, preparation of a draft and final
recovery plan, and periodic revisions to the plan as significant new
information becomes available. The recovery outline guides the
immediate implementation of urgently needed recovery actions and
describes the process to be used to develop a recovery plan. The
recovery plan identifies site-specific management actions that will
achieve recovery of the species, measurable criteria that determine
when a species may be downlisted or delisted, and methods for
monitoring recovery progress. Recovery plans also establish a framework
for agencies to coordinate their recovery efforts and provide estimates
of the cost of implementing recovery tasks. Recovery teams (comprised
of species experts, Federal and State agencies, nongovernment
organizations, and stakeholders) are often established to develop
recovery plans. When completed, the recovery outline, draft recovery
plan, and the final recovery plan will be available on our Web site
(http://www.fws.gov/endangered), or from our Oklahoma Ecological
Services Field Office (see FOR FURTHER INFORMATION CONTACT).
In general, the Service believes conservation and eventual recovery
of the lesser prairie-chicken should consist of the establishment of
secure strongholds or core areas of high quality habitat that are at
least 10,117 ha (25,000 ac) in size and support 6-10 active leks, each
being used by at least 6 males (Applegate and Riley 1998, p. 14).
Ideally these areas would contain minimal amounts of habitat
fragmentation and be managed such that the areas are secure from
pressures of ongoing development. As fragmentation within these areas
increases, the total amount of area would need to expand accordingly
such that the total amount of high quality habitat is at least 10,117
ha. It is expected that a minimum of four strongholds will be needed,
distributed across the ecological diversity of the species, in order to
secure the status of the species. The Service views the species'
occupied range as a matrix comprising four primary quadrants, each one
exemplifying a unique combination of precipitation, temperature, and
vegetation type variables. The quadrants are separated from east to
west by the boundary between the shortgrass prairie and central-mixed-
grass-prairie Bird Conservation Regions and from north to south by the
Canadian River. To ensure redundancy, resiliency, and representation
across the species' range, the Service recommends at least one lesser
prairie-chicken stronghold be established and maintained in each
quadrant. Resiliency refers to the capacity of an ecosystem or an
organism to recover quickly from a disturbance by tolerating or
adapting to the anticipated alterations caused by the disturbance.
Redundancy, in this context, refers to the ability of a species to
compensate for fluctuations in or loss of populations across the
species' range such that the loss of a single population has little or
no lasting effect on the structure and functioning of the species as a
whole. Representation refers to the conservation of the diversity of a
species.
While a minimum of four strongholds is recommended in order to
secure the status of the species, additional strongholds and
connections between them will be needed in order to conserve the
species. A more complete explanation of this preliminary conservation
strategy can be found in the Service's (2012) technical white paper
titled ``Conservation Needs of the Lesser Prairie-chicken'' (available
at http://www.regulations.gov).
Implementation of recovery actions generally requires the
participation of a broad range of partners, including other Federal
agencies, States, Tribal and nongovernmental organizations,
[[Page 73837]]
businesses, and private landowners. Examples of recovery actions
include habitat restoration (e.g., restoration of native vegetation),
research and monitoring, captive propagation and reintroduction, and
outreach and education. Although land acquisition is an example of a
type of recovery action, the recovery of many listed species cannot be
accomplished solely on Federal lands because their range may occur
primarily or solely on non-Federal lands. Consequently, recovery of
these species will require cooperative conservation efforts involving
private, State, and possibly Tribal lands.
If this species is listed, funding for recovery actions will be
available from a variety of sources, including Federal budgets, State
programs, and cost share grants for non-Federal landowners, the
academic community, and nongovernmental organizations. In addition,
under section 6 of the Act, the States of Colorado, Kansas, New Mexico,
Oklahoma, and Texas would be eligible for Federal funds to implement
management actions that promote the protection and recovery of the
lesser prairie-chicken. Information on our grant programs that are
available to aid species recovery can be found at: http://www.fws.gov/grants.
Although the lesser prairie-chicken is only proposed for listing
under the Act at this time, please let us know if you are interested in
participating in recovery efforts for this species. Additionally, we
invite you to submit any new information on this species whenever it
becomes available and any information you may have for recovery
planning purposes (see FOR FURTHER INFORMATION CONTACT).
Federal Agency Consultation
Section 7(a) of the Act, as amended, requires Federal agencies to
evaluate their actions with respect to any species that is proposed or
listed as endangered or threatened and with respect to its critical
habitat, if any is designated. Regulations implementing this
interagency cooperation provision of the Act are codified at 50 CFR
part 402. Section 7(a)(4) requires Federal agencies to confer with the
Service on any action that is likely to jeopardize the continued
existence of a species proposed for listing or result in destruction or
adverse modification of proposed critical habitat. If a species is
listed subsequently, section 7(a)(2) of the Act requires Federal
agencies to ensure that activities they authorize, fund, or carry out
are not likely to jeopardize the continued existence of the species or
destroy or adversely modify its critical habitat. If a Federal action
may adversely affect a listed species or its critical habitat, the
responsible Federal agency must enter into formal consultation with the
Service.
Some examples of Federal agency actions within the species' habitat
that may require conference or consultation, or both, as described in
the preceding paragraph include landscape-altering activities on
Federal lands; provision of Federal funds to State and private entities
through Service programs, such as the PFW Program, State Wildlife Grant
Program, and Federal Aid in Wildlife Restoration program; construction
and operation of communication, radio, and similar towers by the
Federal Communications Commission or Federal Aviation Administration;
issuance of section 404 Clean Water Act permits by the U.S. Army Corps
of Engineers; construction and management of petroleum pipeline and
power line rights-of-way by the Federal Energy Regulatory Commission;
construction and maintenance of roads or highways by the Federal
Highway Administration; implementation of certain USDA agricultural
assistance programs; Federal grant, loan, and insurance programs; or
Federal habitat restoration programs such as EQIP; and development of
Federal minerals, such as oil and gas.
Prohibitions and Exceptions
The purposes of the Act are to provide a means whereby the
ecosystems upon which endangered species and threatened species depend
may be conserved, to provide a program for the conservation of such
endangered species and threatened species, and to take such steps as
may be appropriate to achieve the purposes of the treaties and
conventions set forth in the Act. The Act is implemented through
regulations found in the CFR. When a species is listed as endangered,
certain actions are prohibited under section 9 of the Act, as specified
in 50 CFR 17.21. These prohibitions, which will be discussed further
below, include, among others, take within the United States, within the
territorial seas of the United States, or upon the high seas; import;
export; and shipment in interstate or foreign commerce in the course of
a commercial activity.
The Act does not specify particular prohibitions, or exceptions to
those prohibitions, for threatened species. Instead, under section 4(d)
of the Act, the Secretary of the Interior was given the discretion to
issue such regulations as he deems necessary and advisable to provide
for the conservation of such species. The Secretary also has the
discretion to prohibit by regulation with respect to any threatened
species, any act prohibited under section 9(a)(1) of the Act.
Exercising this discretion, the Service has developed general
prohibitions (50 CFR 17.31) and exceptions to those prohibitions (50
CFR 17.32) under the Act that apply to most threatened species. Under
50 CFR 17.43, permits may be issued to allow persons to engage in
otherwise prohibited acts. Alternately, for other threatened species,
the Service develops specific prohibitions and exceptions that are
tailored to the specific conservation needs of the species. In such
cases, some of the prohibitions and authorizations under 50 CFR 17.31
and 17.32 may be appropriate for the species and incorporated into a
special rule under section 4(d) of the Act, but the 4(d) special rule
will also include provisions that are tailored to the specific
conservation needs of the threatened species and which may be more or
less restrictive than the general provisions at 50 CFR 17.31.
For example, for several fish species that are listed as threatened
species, the Service has prepared a 4(d) special rule. In these
situations, threatened fish co-occur with other species that are not
listed as threatened or endangered species. Recreational fishing of the
non-listed species may occur in these areas, usually under a permit or
license program managed by the State Conservation Agency. In some of
these cases, the Service has prepared a 4(d) special rule which
generally prohibits the activities that are defined in the Act for
endangered species, but does not prohibit take if it is incidental to
recreational fishing activities that are conducted pursuant to an
appropriate State program.
Similarly, we are considering whether it is appropriate to fashion
a 4(d) rule that would not prohibit take that is incidental to
implementing a sector-specific or comprehensive lesser prairie-chicken
conservation program. We anticipate that conservation programs given
credit under such a 4(d) rule would need to be developed and
administered by an entity having jurisdiction or authority over the
activities in the program; would need to be approved by the Service as
adequately protective to provide a net conservation benefit to the
lesser prairie-chicken; and would need to include robust adaptive
management, monitoring, and reporting components sufficient to
demonstrate that the conservation objectives of the plan are being met.
Several ongoing conservation efforts may satisfy or be moving
toward this end, such as the Lesser Prairie-Chicken
[[Page 73838]]
Initiative, implementation of a multi-State rangewide conservation
strategy, or individual candidate conservation agreements with
assurances that currently have permits issued pursuant to section 10 of
the Act.
Accordingly, we are soliciting public comment as to which
prohibitions, and exceptions to those prohibitions, are necessary and
advisable to provide for the conservation of the lesser prairie-chicken
(see Public Comments above). After reviewing the initial public
comments on this topic, we will evaluate whether a 4(d) special rule is
appropriate for the lesser prairie-chicken, and, if so, publish a
proposed 4(d) special rule for public comment.
Currently, we have not proposed a 4(d) special rule for the lesser
prairie-chicken. If the lesser prairie-chicken is ultimately listed as
a threatened species without a 4(d) special rule, the general
prohibitions (50 CFR 17.31) and exceptions to these prohibitions (50
CFR 17.32) for threatened species would be applied to the lesser
prairie-chicken, as explained above. The prohibitions of section
9(a)(2) of the Act, codified at 50 CFR 17.31 for threatened wildlife,
in part, make it illegal for any person subject to the jurisdiction of
the United States to take (includes harass, harm, pursue, hunt, shoot,
wound, kill, trap, capture, or collect; or to attempt any of these),
import, export, ship in interstate commerce in the course of commercial
activity, or sell or offer for sale in interstate or foreign commerce
any listed species. Under the Lacey Act (18 U.S.C. 42-43; 16 U.S.C.
3371-3378), it is also illegal to possess, sell, deliver, carry,
transport, or ship any such wildlife that has been taken illegally.
Certain exceptions apply to agents of the Service and State
conservation agencies.
We may issue permits to carry out otherwise prohibited activities
involving endangered and threatened wildlife species under certain
circumstances. Regulations governing permits are codified at 50 CFR
17.32 for threatened species. A permit must be issued for the following
purposes: for scientific purposes, to enhance the propagation or
survival of the species, and for incidental take in connection with
otherwise lawful activities. We anticipate that we would receive
requests for all three types of permits, particularly as they relate to
development of wind power facilities or implementation of Safe Harbor
Agreements. Requests for copies of the regulations regarding listed
species and inquiries about prohibitions and permits may be addressed
to the Field Supervisor at the address in the FOR FURTHER INFORMATION
CONTACT section.
It is our policy, as published in the Federal Register on July 1,
1994 (59 FR 34272), to identify to the maximum extent practicable at
the time a species is listed, those activities that would or would not
constitute a violation of section 9 of the Act. The intent of this
policy is to increase public awareness of the effect of a proposed
listing on proposed and ongoing activities within the range of species
proposed for listing. The following activities could potentially result
in a violation of section 9 of the Act; this list is not comprehensive:
(1) Unauthorized collecting, handling, possessing, selling,
delivering, carrying, or transporting of the species, including import
or export across State lines and international boundaries, except for
properly documented antique specimens of these taxa at least 100 years
old, as defined by section 10(h)(1) of the Act.
(2) Actions that would result in the unauthorized destruction or
alteration of the species' habitat, as previously described in this
rule. Such activities could include, but are not limited to, the
removal of native shrub or herbaceous vegetation by any means for any
infrastructure construction project or direct conversion of native
shrub or herbaceous vegetation to another land use.
(3) Actions that would result in the long-term (e.g., greater than
3 years) alteration of preferred vegetative characteristics of lesser
prairie-chicken habitat, as previously described in this proposed rule,
particularly those actions that would cause a reduction or loss in the
native invertebrate community within those habitats. Such activities
could include, but are not limited to, inappropriate livestock grazing,
the application of herbicides or insecticides, and seeding of nonnative
plant species that would compete with native vegetation for water,
nutrients, and space.
(4) Actions that would result in lesser prairie-chicken avoidance
of an area during one or more seasonal periods. Such activities could
include, but are not limited to, the construction of vertical
structures such as power lines, fences, communication towers, and
buildings; motorized and nonmotorized recreational use; and activities
such as well drilling, operation, and maintenance, which would entail
significant human presence, noise, and infrastructure.
Questions regarding whether specific activities would constitute a
violation of section 9 of the Act should be directed to the Oklahoma
Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).
Background
Species Information
The lesser prairie-chicken (Tympanuchus pallidicinctus) is a
species of prairie grouse endemic to the southern high plains of the
United States, commonly recognized for its feathered feet, stout build,
ground-dwelling habit, and lek mating behavior. The lesser prairie-
chicken is closely related and generally similar, although not
identical in every aspect of behavior and life history, to other
species of North American prairie grouse (e.g., greater prairie-chicken
(T. cupido pinnatus), Attwater's prairie-chicken (T. cupido attwateri),
sharp-tailed grouse (T. phasianellus), greater sage-grouse
(Centrocercus urophasianus), and Gunnison's sage-grouse (C. minimus)).
Plumage of the lesser prairie-chicken is characterized by a cryptic
pattern of alternating brown and buff-colored barring, and is similar
in mating behavior and appearance, although somewhat lighter in color,
to the greater prairie-chicken. Males have long tufts of feathers on
the sides of the neck, termed pinnae, that are erected during courtship
displays. Pinnae are smaller and less prominent in females. Males also
display brilliant yellow supraorbital eyecombs and dull reddish
esophageal air sacs during courtship displays (Copelin 1963, p. 12;
Sutton 1977, entire; Johnsgard 1983, p. 318). A more detailed summary
of the appearance of the lesser prairie-chicken is provided in Hagen
and Giesen (2005, unpaginated).
Lesser prairie-chickens are dimorphic in size, with the females
being smaller than the males (See Table 1 in Hagen and Giesen 2005,
unpaginated). Adult lesser prairie-chicken body length varies from 38
to 41 centimeters (cm) (15 to 16 inches (in)) (Johnsgard 1973, p. 275;
Johnsgard 1983, p. 318), and body mass varies from 734 to 813 grams (g)
(1.6 to 1.8 pounds (lbs)) for males and 628 to 772 g (1.4 to 1.7 lbs)
for females (Giesen 1998, p. 14). Adults weigh more than yearling
birds.
Taxonomy
The lesser prairie-chicken is in the Order Galliformes, Family
Phasianidae, subfamily Tetraoninae, and is recognized as a species
separate from the greater prairie-chicken (Jones 1964, pp. 65-73;
American Ornithologist's Union 1998, p. 122). The lesser prairie-
chicken was first described as a subspecies of the greater prairie-
chicken (Ridgway 1873, p. 199) but was later
[[Page 73839]]
named a full species in 1885 (Ridgway 1885, p. 355). Additional
information on lesser prairie-chicken systematics and taxonomy can be
found in Hagen and Giesen (2005, unpaginated).
Life-History Characteristics
Lesser prairie-chickens are polygynous (a mating pattern in which a
male mates with more than one female in a single breeding season) and
exhibit a lek mating system. The lek is a place where males
traditionally gather to conduct a communal, competitive courtship
display. The males use their specialized plumage and vocalizations to
attract females for mating. The sequence of vocalizations and posturing
of males, often described as ``booming, gobbling, yodeling, bubbling,
or duetting,'' has been described by Johnsgard (1983, p. 336) and
Haukos (1988, pp. 44-45) and is well summarized by Hagen and Giesen
(2005, unpaginated). Male lesser prairie-chickens gather to display on
leks at dawn and dusk beginning as early as late January and continuing
through mid-May (Copelin 1963, p. 26; Hoffman 1963, p. 730; Crawford
and Bolen 1976a, p. 97; Sell 1979, p. 10; Merchant 1982, p. 40),
although fewer numbers of birds generally attend leks during the
evening (Taylor and Guthery 1980a, p. 8). Male birds may remain on the
lek for up to 4 hours (Copelin 1963, pp. 27-28; Sharpe 1968, p. 76;
Crawford and Bolen 1975, pp. 808-810; Giesen 1998, p. 7), with females
typically departing the lek following successful copulation (Sharpe
1968, pp. 154, 156). Dominant, usually older, males occupy and defend
territories near the center of the lek where most of the copulations
occur, while younger males occupy the periphery and compete for central
access (Sharpe 1968, pp. 73-89; Wiley 1974, p. 203; Ehrlich et al.
1988, p. 259). A relatively small number of dominant males account for
the majority of copulations at each lek (Sharpe 1968, p. 87; Wiley
1974, p. 203; Locke 1992, p. 1). Young males are rarely successful in
breeding due to the dominance by older males. The spring display period
may extend into June (Hoffman 1963, p. 730; Jones 1964, p. 66);
however, Jones (1964, p. 66) observed some courtship activity even
during July in Oklahoma.
Male lesser prairie-chickens exhibit strong site fidelity (loyalty
to a particular area; philopatry) to their display grounds (Copelin
1963, pp. 29-30; Hoffman 1963, p. 731; Campbell 1972, pp. 698-699).
Such behavior is typical for most species of prairie grouse (e.g.,
greater prairie-chicken, lesser prairie-chicken, sharp-tailed grouse,
greater sage-grouse, and Gunnison's sage-grouse) in North America
(Schroeder and Robb 2003, pp. 231-232). Once a lek site is selected,
males persistently return to that lek year after year (Wiley 1974, pp.
203-204) and may remain faithful to that site for life. They often will
continue to use these traditional areas even when the surrounding
habitat has declined in value (for example, concerning greater sage-
grouse; see Harju et al. 2010, entire). Female lesser prairie-chickens,
due to their tendency to nest within 2.5 km (1.5 mi) of a lek (Giesen
1994a, p. 97), also may display fidelity to nesting areas but the
degree of fidelity is not clearly established (Schroeder and Robb 2003,
p. 292). However, Haukos and Smith (1999, p. 418) observed that female
lesser prairie-chickens are more likely to visit older, traditionally
used lek sites than temporary, nontraditional lek sites (those used for
no more than 2 years). Temporary or satellite leks occasionally may be
established during the breeding season and appear indicative of
population fluctuations (e.g., an expanding population has more
satellite leks than a declining population) (Hamerstrom and Hamerstrom
1973, pp. 7, 13; Schroeder and Braun 1992, p. 280; Haukos and Smith
1999, pp. 415, 417) or habitat quality (Cannon and Knopf 1979, p. 44;
Merrill et al. 1999, pp. 193-194). Lesser prairie-chicken satellite
leks have been observed to form later in the breeding season and
coincide with decreased attendance at the permanent leks (Haukos and
Smith 1999, p. 418). These satellite leks consisted primarily of birds
that were unable to establish territories on the permanent leks (Haukos
and Smith 1999, p. 418). Locations of traditional, permanent lek sites
also may change in response to disturbances (Crawford and Bolen 1976b,
pp. 238-240; Cannon and Knopf 1979, p. 44).
Because of this fidelity to breeding areas, prairie grouse may not
immediately demonstrate a population response when faced with
environmental change. Considering that landscapes and habitat
suitability can change rapidly, strong site fidelity can result in a
lag period between when a landscape degradation occurs and when a
population response is observed (Gregory et al. 2011, pp. 29-30). In
some birds exhibiting strong philopatry, Wiens et al. (1986, p. 374)
thought that the overall response to a particular habitat alteration
might not become evident until after the most site-tenacious
individuals had died. Delayed population responses have been observed
in birds impacted by wind energy development (Stewart et al. 2007, pp.
5-6) and in greater sage-grouse impacted by oil and gas development
(Doherty et al. 2010, p. 5). Consequently routine lek count surveys
typically used to monitor prairie grouse may be slow in revealing
impacts of environmental change (Gregory et al. 2011, pp. 29-30).
Leks are normally located on the tops of wind-swept ridges, exposed
knolls, sparsely vegetated dunes, and similar features in areas having
low vegetation height or bare soil and enhanced visibility of the
surrounding area (Copelin 1963, p. 26; Jones 1963a, p. 771; Taylor and
Guthery 1980a, p. 8). The features associated with lek sites also may
contribute to the transmission of sounds produced during lekking
(Butler et al. 2010, entire) and these sounds may aid females in
locating lek sites (Hagen and Giesen 2005, unpaginated). Background
noises are known to increase in landscapes altered by human development
and may interfere with normal behavioral activities (Francis et al.
2009, p. 1415). Birds may be particularly vulnerable to elevated levels
of background noise, due to their reliance on acoustic communication,
and elevated noise levels may negatively impact breeding in some birds
particularly where acoustic cues are used during the reproductive
process (Francis et al. 2009, pp. 1415, 1418).
Areas that have been previously disturbed by humans, such as
infrequently used roads, abandoned drilling pads, abandoned farmland,
recently cultivated fields, and livestock watering sites also can be
used as lek sites (Crawford and Bolen 1976b, pp. 238-239; Davis et al.
1979, pp. 81, 83; Sell 1979, p. 14; Taylor 1979, p. 707). However,
ongoing human activity, such as presence of humans or noise, may
discourage lekking by causing birds to flush, and, in some instances,
may cause lek sites to be abandoned (Hunt and Best 2004, pp. 2, 124).
Leks often are surrounded by taller, denser cover that is used for
escape, thermal cover, and feeding cover. New leks can be formed
opportunistically at any appropriate site within or adjacent to nesting
habitat. Evidence of expanding lesser prairie-chicken populations tends
to be demonstrated by increases in the number of active leks rather
than by increases in the number of males displaying per lek (Hoffman
1963, p. 731; Snyder 1967, p. 124; Cannon and Knopf 1981, p. 777;
Merchant 1982, p. 54; Locke 1992, p. 43).
Females arrive at the lek in early spring after the males begin
displaying, with peak hen attendance at leks
[[Page 73840]]
typically occurring in early to mid-April (Copelin 1963, p. 26; Hoffman
1963, p. 730; Crawford and Bolen 1975, p. 810; Davis et al. 1979, p.
84; Merchant 1982, p. 41; Haukos 1988, p. 49). Sounds produced by
courting males serve to advertise the presence of the lek to females in
proximity to the display ground (Robb and Schroeder 2005, p. 29).
Within 1 to 2 weeks of successful mating, the hen will select a nest
site, normally within 1 to 3 km (0.6 to 2 mi) of a lek (Copelin 1963,
p. 44; Giesen 1994a, p. 97), construct a nest, and lay a clutch of 8 to
14 eggs (Bent 1932, p. 282; Copelin 1963, p. 34; Merchant 1982, p. 44;
Fields 2004, pp. 88, 115-116; Hagen and Giesen 2005, unpaginated;
Pitman et al. 2006a, p. 26). Nesting is generally initiated in mid-
April and concludes in late May (Copelin 1963, p. 35; Snyder 1967, p.
124; Merchant 1982, p. 42; Haukos 1988, pp. 7-8). Hens most commonly
lay one egg per day and initiate incubation once the clutch is complete
(Hagen and Giesen 2005, unpaginated). Incubation lasts 24 to 27 days
(Coats 1955, p. 18; Sutton 1968, p. 679; Pitman et al. 2006a, p. 26)
with hatching generally peaking in late May through mid-June (Copelin
1963, p. 34; Merchant 1982, p. 42; Pitman et al. 2006a, p. 26). Hens
typically leave the nest within 24 hours after the first egg hatches
(Hagen and Giesen 2005, unpaginated). Renesting may occur when the
first attempt is unsuccessful (a successful nest is one in which at
least one egg hatches) (Johnsgard 1973, pp. 63-64; Merchant 1982, p.
43; Pitman et al. 2006a, p. 25). Renesting is more likely when nest
failure occurs early in the nesting season and becomes less common as
the nesting season progresses (Pitman et al. 2006a, p. 27). Clutches
associated with renesting attempts tend to be smaller than clutches at
first nesting (Fields 2004, p. 88; Pitman et al. 2006a, p. 27).
Nests generally consist of bowl-shaped depressions in the soil
(Giesen 1998, p. 9). Nests are lined with dried grasses, leaves, and
feathers, and there is no evidence that nests are reused in subsequent
years (Giesen 1998, p. 9). Adequate herbaceous cover, including
residual cover from the previous growing season, is an important factor
influencing nest success, primarily by providing concealment of the
nest (Suminski 1977, p. 32; Riley 1978, p. 36; Riley et al. 1992, p.
386; Giesen 1998, p. 9). Young are precocial (mobile upon hatching) and
nidifugous (typically leaving the nest within hours of hatching) (Coats
1955, p. 5). Chicks are usually capable of short flights by 14 days of
age (Hagen and Giesen 2005, unpaginated). Broods may remain with
females for up to 18 weeks (Giesen 1998, p. 9; Pitman et al. 2006c, p.
93), but brood breakup generally occurs by September when the chicks
are approximately 70 days of age (Taylor and Guthery 1980a, p. 10).
Males do not incubate the eggs, assist in chick rearing, or provide
other forms of parental care (Wiley 1974, p. 203). Nest success
(proportion of nests that hatch at least one egg) varies, but averages
about 30 percent (range 0-67 percent) (Hagen and Giesen 2005,
unpaginated).
Availability of food and cover are key factors that affect chick
and juvenile survival. Chick survival averaged only about 25 percent
during the first 35 days following hatching (Hagen 2003, p. 135).
Survival for chicks between 35 days of age and the following spring was
estimated to be 53.9 percent in southwestern Kansas (Hagen et al. 2009,
p. 1326). Jamison (2000, p. 57) estimated survival of chicks from
hatching to early autumn (60 days post-hatching), using late summer
brood sizes provided in several early studies, to be 27 percent in
Kansas and 43-65 percent in Oklahoma. These values were considerably
higher than the 19 percent he observed in his study and may reflect an
inability in the earlier studies to account for the complete loss of
broods and inclusion of mixed broods (combined broods from several
females) when estimating brood size (Jamison 2000, p. 57). Pitman et
al. (2006b, p. 677) estimated survival of chicks from hatching to 60-
days post-hatching to be 17.7 percent. Recruitment was characterized as
low with survival of juvenile birds from hatching to the start of the
first breeding season the following year estimated to be only 12
percent (Pitman et al. 2006b, pp. 678-680), which may be a significant
limiting factor in southwestern Kansas. However, the authors cautioned
that these estimates might not be indicative of survival estimates in
other areas due to low habitat quality, specifically poor distribution
of nesting and brood-rearing habitats within the study area (Pitman et
al. 2006b, p. 680).
Lesser prairie-chicken home ranges vary both by sex and by season
and may be influenced by a variety of factors. Males tend to have
smaller home ranges than do females, with the males generally remaining
closer to the leks than do the females (Giesen 1998, p. 11). In
Colorado, Giesen (1998, p. 11) observed that spring and summer home
ranges for males were 211 ha (512 ac) and for females were 596 ha
(1,473 ac). In the spring, home ranges are fairly small when daily
activity focuses on lekking and mating. Home ranges of nesting females
in New Mexico varied, on average, from 8.5 to 92 ha (21 to 227 ac)
(Merchant 1982, p. 37; Riley et al. 1994, p. 185). Jamison (2000, p.
109) observed that range size peaked in October as birds began feeding
in recently harvested grain fields. Median range size in October was
229 to 409 ha (566 to 1,400 ac). In Texas, Taylor and Guthery (1980b,
p. 522) found that winter monthly home ranges for males could be as
large as 1,945 ha (4,806 ac) and that subadults tended to have larger
home ranges than did adults. More typically, winter ranges are more
than 300 ha (740 ac) in size, and the size declines considerably by
spring. Based on observations from New Mexico and Oklahoma, lesser
prairie-chicken home ranges increase during periods of drought (Giesen
1998, p. 11; Merchant 1982, p. 55), possibly because of reduced food
availability and cover. Davis (2005, p. 3) states that the combined
home range of all lesser prairie-chickens at a single lek is about 49
square kilometers (sq km) (19 square miles (sq mi) or 12,100 ac).
Many grouse species are known to be relatively poor dispersers and
normally move less than 40 km (25 mi) (Braun et al. 1994, pp. 432-433).
Dispersal helps maintain healthy, robust populations by contributing to
population expansion, recolonization, and gene flow (Sutherland et al.
2000, unpaginated). In lesser prairie-chickens, most movements within a
given season are less than 10 km (6.2 mi), but Jamison (2000, p. 107)
thought that movements as large as 44 km (27.3 mi) might occur in
fragmented landscapes. Recent studies of lesser prairie-chicken in
Kansas demonstrated some birds may move as much as 50 km (31 mi) from
their point of capture (Hagen et al. 2004, p. 71). Although recorded
dispersal movements indicate that lesser prairie-chickens are obviously
physically capable of longer distance dispersal movements, these longer
movements appear to be infrequent. Jamison (2000, p. 107) recorded only
2 of 76 tagged male lesser prairie-chickens left the 5,760 ha (14,233
ac) primary study area over a 3-year period. He thought site fidelity
rather than habitat was more important in influencing movements of male
lesser prairie-chickens (Jamison 2000, p. 111). Environmental factors
also may influence dispersal patterns, particularly in fragmented
landscapes where predation rates may be higher and habitat suitability
may be reduced in smaller sized parcels. Lesser prairie-chickens appear
to be sensitive to the size of habitat fragments and may avoid using
parcels below a preferred size
[[Page 73841]]
regardless of habitat type or quality (see separate discussion under
``Effects of Habitat Fragmentation'' below). As the landscape becomes
more fragmented, longer dispersal distances over areas of unsuitable
habitats may be required.
Daily movements of males tend to increase in fall and winter and
decrease with onset of spring, with median daily movements typically
being less than 786 meters per day (Jamison 2000, pp. 106, 112). In
Texas, Haukos (1988, p. 46) recorded daily movements of 0.1 km (0.06
mi) to greater than 6 km (3.7 mi) by female lesser prairie-chickens
prior to onset of incubation. Taylor and Guthery (1980b, p. 522)
documented a single male moving 12.8 km (8 mi) in 4 days, which they
considered to be a dispersal movement. Because lesser prairie-chickens
exhibit limited dispersal ability and do not typically disperse over
long distances, they do not readily recolonize areas following
localized extinctions, particularly where the distance between habitat
patches exceeds their typical dispersal capabilities.
In general, there is little documentation of historical dispersal
patterns, and the existence of large-scale migration movements is not
known. However, both Bent (1932, pp. 284-285) and Sharpe (1968, pp. 41-
42) thought that the species, at least historically, might have been
migratory with separate breeding and wintering ranges. Taylor and
Guthery (1980a, p. 10) also thought the species was migratory prior to
widespread settlement of the High Plains, but migratory movements have
not recently been documented. The lesser prairie-chicken is now thought
to be nonmigratory.
Lesser prairie-chickens forage during the day, usually during the
early morning and late afternoon, and roost at night (Jones 1964, p.
69). Diet of the lesser prairie-chicken is very diverse, primarily
consisting of insects, seeds, leaves, and buds and varies by age,
location, and season (Giesen 1998, p. 4). They forage on the ground and
within the vegetation layer (Jones 1963b, p. 22) and are known to
consume a variety of invertebrate and plant materials. For example, in
New Mexico, Smith (1979, p. 26) documented 30 different kinds of food
items consumed by lesser prairie-chickens. In Texas, Crawford and Bolen
(1976c, p. 143) identified 23 different plants in the lesser prairie-
chicken diet. Jones (1963a, pp. 765-766), in the Artemesia filifolia
(sand sagebrush) dominated grasslands of Oklahoma, recorded 16
different plant species eaten by lesser prairie-chickens.
Lesser prairie-chicken energy demands are almost entirely derived
from daily foraging activities rather than stored fat reserves (Giesen
1998, p. 4). Olawsky (1987, p. 59) found that, on average, lesser
prairie-chicken body fat reserves were less than 4.5 percent of body
weight. Consequently, quality and quantity of food consumed can have a
profound effect on the condition of individual birds. Inadequate food
supplies and reduced nutritional condition can affect survival,
particularly during harsh winters, and reproductive potential. Poor
condition can lead to poor performance on display grounds, impact
nesting success, and reduce overwinter survival. Sufficient nutrients
and energy levels are important for reproduction and overwintering.
Males expend energy defending territories and mating while females have
demands of nesting, incubation, and any renesting. Reduced condition
can lead to smaller clutch sizes. Because lesser prairie-chicken diets
vary considerably by age, season, and habitat type and quality, habitat
alteration can influence availability of certain foods. While not as
critical for adults, presence of forbs and associated insect
populations can be very important for proper growth and development of
chicks and poults.
Generally, chicks and young juveniles tend to forage almost
exclusively on insects, such as grasshoppers and beetles, and other
animal matter while adults tend to consume a higher percentage of
vegetative material (Giesen 1998, p. 4). The majority of the published
diet studies have been conducted in the southwestern portions of the
historical range where the Quercus havardii (shinnery oak) dominated
grasslands are prevalent. Throughout their range, when available,
lesser prairie-chickens will use cultivated grains, such as Sorghum
vulgare (grain sorghum) and Zea mays (corn), during the fall and winter
months (Snyder 1967, p. 123; Campbell 1972, p. 698; Crawford and Bolen
1976c, pp. 143-144; Ahlborn 1980, p. 53; Salter et al. 2005, pp. 4-6).
However, lesser prairie-chickens tend to predominantly rely on
cultivated grains when production of natural foods, such as acorns and
grass and forb seeds are deficient (Copelin 1963, p. 47; Ahlborn 1980,
p. 57).
Food availability for gamebird young is most critical during the
first 20 days (3 weeks) post-hatching when rapid growth is occurring
(Dobson et al. 1988, p. 59). Diet of lesser prairie-chicken chicks less
than 5 weeks of age is entirely composed of insects and similar animal
matter. Specifically, diet of chicks in New Mexico that were less than
2 weeks of age was 80 percent treehoppers (Mebracidae) (Davis et al.
1979, p. 71; Davis et al. 1980 p. 78). Overall, chicks less than 5
weeks of age consumed predominantly (87.7 percent) short-horned
grasshoppers (Acrididae), treehoppers, and long-horned grasshoppers
(Tettigonidae) (Davis et al. 1980, p. 78). Ants (Formicidae), mantids
(Mantidae), snout beetles (Curculionidae), darkling beetles
(Tenebrionidae), robber flies (Asilidae), and cockroaches (Blattidea)
collectively provided the remaining 12.3 percent of the chicks' diet
(Davis et al. 1980, p. 78). Similarly Suminski (1977, pp. 59-60)
examined diet of chicks 2 to 4 weeks of age in New Mexico and found
that diet was entirely composed of insects. Treehoppers, short-horned
grasshoppers, and ants were the most significant (95 percent) items
consumed, by volume. Insects and similar animal matter are a
particularly prevalent component in the diet of young prairie-chickens
(Drake 1994, pp. 31, 34, 36). Insects are high in protein (Riley et al.
1998, p. 42), and a high-protein diet was essential in pheasants for
normal growth and feather development (Woodward et al. 1977. p. 1500).
Insects and other arthropods also have been shown to be extremely
important in the diet of young sage grouse and Attwater's prairie-
chicken (Service 2010, pp. 30-31).
Older chicks between 5 and 10 weeks of age ate almost entirely
short-horned grasshoppers (80.4 percent) (Davis et al. 1980, p. 78).
They also began to consume plant material during this period. Shinnery
oak acorns, seeds of Lithospermum incisum (narrowleaf stoneseed), and
foliage and flowers of Commelina erecta (erect dayflower) comprised
less than 1 percent of the diet (Davis et al. 1980, p. 78).
Correspondingly, Suminski (1977, pp. 59, 61) observed that chicks
between 6 and 10 weeks of age had begun to consume very small
quantities (1.3 percent by volume) of plant material. The remainder of
the diet was still almost entirely composed of insects. By far the most
prevalent insect was short-horned grasshoppers (Acrididae), accounting
for 73.9 percent of the diet (Davis et al. 1980, p. 78). As the birds
grew, the sizes of insects eaten increased. Analysis of food habits of
juvenile birds from 20 weeks of age and older, based on samples
collected between August and December, revealed that 82.6 percent of
diet was plant material by volume and 17.4 percent was invertebrates
(Suminski 1977, p. 62). Shinnery oak acorns contributed 67 percent of
the overall diet, by volume. Key insects included crickets (Gryllidae),
short-horned grasshoppers,
[[Page 73842]]
mantids, and butterfly (Lepidoptera) larvae.
Plant materials are a principal component of the diet for adult
lesser prairie-chickens; however, the composition of the diet tends to
vary by season and habitat type. The majority of the diet studies
examined foods contained in the crop (an expanded, muscular pouch
within the digestive tract of most birds that aids in breakdown and
digestion of foods) and were conducted in habitats supporting shinnery
oak. However, Jones (1963b, p. 20) reported on lesser prairie-chicken
diets from sand sagebrush habitats.
In the spring (March, April, and May), lesser prairie-chickens fed
heavily on green vegetation (60 to 79 percent) and mast and seeds (15
to 28 percent) (Davis et al. (1980, p. 76; Suminski 1977, p. 57).
Insects comprised less than 13 percent of the diet primarily due to
their relative scarcity in the spring months. Treehoppers and beetles
were the most common types of insects found in the spring diet. The
proportion of vegetative material provided by shinnery oak leaves,
catkins, and acorns was high. Similarly, Doerr (1980, p. 8) also
examined the spring diet of lesser prairie-chickens. However, he
compared diets between areas treated with the herbicide tebuthiuron and
untreated areas, and it is unclear whether the birds he examined came
from treated or untreated areas. Birds collected from treated areas
likely would have limited access to shinnery oak, possibly altering the
observed occurrence of shinnery oak in the diet. He reported that
animal matter was the dominant component of the spring diet and largely
consisted of short-horned grasshoppers and darkling beetles (Doerr
1980, pp. 30-31). Ants, ground beetles (Carabidae), and stinkbugs
(Pentatomidae) were slightly less prevalent in the diet. Shinnery oak
acorns and plant seeds were the least common component, by volume, in
the diet in the Doerr (1980) studies.
In the summer, insects become a more important component of the
diet. In New Mexico, insects comprised over half (55.3 percent) of the
overall summer (June, July, and August) diet with almost half (49
percent) of the insects being short- and long-horned grasshoppers and
treehoppers (Davis et al. 1980, p. 77). Plant material consumed was
almost equally divided between foliage (leaves and flowers; 23.3
percent) and mast and seeds (21.4 percent). Shinnery oak parts
comprised 22.5 percent of the overall diet. Olawsky (1987, pp. 24, 30)
also examined lesser prairie-chicken diets during the summer season
(May, June, and July); however, he also compared diets between areas
treated with tebuthiuron and untreated pastures in Texas and New
Mexico. While the diets in treated and untreated areas were different,
the diet from the untreated area should be representative of a typical
summer diet. Total plant matter from birds collected from the untreated
areas comprised 68 to 81 percent, by volume (Olawsky 1987, pp. 30-32).
Foliage comprised 21 to 25 percent, and seeds and mast, 36 to 60
percent, of the diet from birds collected in the untreated area.
Shinnery oak acorns were the primary form of seeds and mast consumed.
Animal matter comprised 19 to 32 percent of the overall diet, and
almost all of the animal matter consisted of treehoppers and short-
horned grasshoppers (Olawsky 1987, pp. 30-32).
Several studies have reported on the fall and winter diets of
lesser prairie-chickens. Davis et al. (1979, pp. 70-80), Smith (1979,
pp. 24-32), and Riley et al. (1993, pp. 186-189) all reported on lesser
prairie-chicken food habits from southeastern New Mexico (Chaves
County), where the birds had no access to grain fields (Smith 1979, p.
31). They generally found that fall (October to early December) and
winter (January and February) diets generally consist of a mixture of
seeds, vegetative material, and insects.
The fall diet differed between years primarily due to reduced
availability of shinnery oak acorns (Smith 1979, p. 25). Reduced
precipitation in the fall of 1976 was thought to have influenced acorn
production in 1977 (Riley et al. 1993, pp. 188). When acorns were
available, shinnery oak acorns comprised almost 62 percent, by volume,
of the diet but less than 17 percent during a year when the acorn crop
failed (Smith 1979, p. 26). On average, total mast and seeds consumed
was 43 percent, vegetative material was 39 percent, and animal matter
was 18 percent by volume of the fall diet (Davis et al. 1979, p. 76).
Over 81 percent of the animal matter consumed was short-horned
grasshoppers (Davis et al. 1979, p. 76).
Crawford (1974, pp. 19-20, 35-36) and Crawford and Bolen (1976c,
pp. 142-144) reported on the fall (mid-October) diet of lesser prairie-
chickens in west Texas over a 3-year period. Twenty-three species of
plants were identified from the crops over the course of the study.
Plant matter accounted for 90 percent of the food present by weight and
81 percent by volume. Grain sorghum also was prevalent, comprising 63
percent by weight and 43 percent by volume of total diet. Alhborn
(1980, pp. 53-58) also documented use of grain sorghum during the fall
and winter in eastern New Mexico. The remainder of the diet (10 percent
by weight and 19 percent by volume) was animal matter (insects only).
Over 62 percent, by volume, of the animal matter was composed of short-
horned grasshoppers. Other insects that were important in the diet
included darkling beetles, walking sticks (Phasmidae), and wingless
long-horned grasshoppers (Gryllacrididae). During the fall and winter
in eastern New Mexico, Alhborn (1980, pp. 53-58) reported that
vegetative material from shinnery oak constituted 21 percent of the
total diet.
Similarly, Doerr (1980, p. 32) reported on the lesser prairie-
chickens from west Texas in the fall (October). The diet largely
comprised animal matter (86 percent by volume) with short-horned
grasshoppers contributing 81 percent by volume of the total diet.
Stinkbugs also were prevalent in the diet. Foliage was the least
important component, consisting of only 2.5 percent by volume. Seeds
and acorns comprised 11 percent of the diet and consisted entirely of
shinnery oak acorns and seeds of Linum rigidum (stiffstem flax).
Shinnery oak acorns (69 percent) and annual buckwheat (14 percent)
were the primary components of the winter (January and February) diet
of lesser prairie-chickens in southeastern New Mexico (Riley et al.
1993, p. 188). Heavy selection for acorns in winter was attributed to
need for a high energy source to help sustain body temperature in cold
weather (Smith 1979, p. 28). Vegetative matter was about 26 percent of
overall diet, by volume, with 5 percent of the diet consisting of
animal matter, almost entirely comprising ground beetles (Carabidae)
(Davis et al. 1979, p. 78).
In contrast to the above studies, Jones (1963b, p. 20) and Doerr
(1980, p. 8) examined food items present in the droppings rather than
from the crops. Although this approach is valid, differential digestion
of the food items likely overemphasizes the importance of indigestible
items and underrepresents occurrence of foods that are highly
digestible (Jones 1963b, p. 21; Doerr 1980, pp. 27, 33). Jones' study
site was located in the sand sagebrush dominated grasslands in the more
northern portion of the historical range where shinnery oak was
unavailable. However, Doerr's study site was located in the shinnery
oak dominated grasslands of the southwest Texas panhandle.
In the winter (December through February), where Rhus trilobata
(skunkbush sumac) was present, Jones (1963b, pp. 30, 34) found lesser
prairie-chickens primarily used sumac buds
[[Page 73843]]
and foliage of sumac, sand sagebrush, and Gutierrezia sarothrae (broom
snakeweed), particularly when snow was on the ground. Small annual
plants present in the diet were Vulpia (Festuca) octoflora (sixweeks
fescue), annual buckwheat, and Evax prolifera (big-headed evax;
bigheaded pygmycudweed) (Jones 1963b, p. 30). Grain sorghum wasn't used
to any appreciable extent, particularly when skunkbush sumac was
present, but was eaten when available. Relatively few insects were
available during the winter period. However, beetles were consumed
throughout the winter season and grasshoppers were important in
December. Doerr (1980, p. 28) found grasshoppers, crickets, ants, and
wasps were the most commonly observed insects in the winter diet.
Foliage from sand sagebrush and Cryptantha cinerea (James' cryptantha)
was prevalent, but shinnery oak acorns were by far the most significant
plant component detected in the winter diet.
In the spring (March through May), lesser prairie-chickens used
seeds and foliage of early spring annuals such as Viola bicolor (johnny
jumpup) and Silene antirrhina (sleepy catchfly) (Jones 1963b, p. 49).
Skunkbush sumac continued to be an important component of the diet.
Insect use increased as the spring season progressed. Doerr (1980, p.
29) also observed that grasshoppers and crickets were prevalent in the
spring diet. However, foliage and acorns of shinnery oak were more
abundant in the diet than any other food item.
In the summer (June through August), lesser prairie-chickens
continued to use sumac and other plant material, but insects dominated
the diet (Jones 1963b. pp. 64-65). Grasshoppers were the principal item
found in the diet, but beetles were particularly favored in shrubby
habitats. Similarly, Doerr (1980, p. 25) found grasshoppers and
crickets were the most important component of the summer diet followed
in importance by beetles. Jones (1963b, pp. 64-65) reported fruits from
skunkbush sumac to be the most favored plant material in the diet.
Doerr (1980, p. 25) found James cryptantha and erect dayflower were the
two most important plants in the diet in his study. Insects remained a
principal food item in the fall (September through November), at least
until November when plant foods, such as Cyperus schweinitzii
(flatsedge) and Ambrosia psilostachya (western ragweed) became more
prevalent in the diet (Jones 1963b, pp. 80-81).
Little is known regarding the specific water requirements of the
lesser prairie-chicken, but their distribution does not appear to be
influenced by the presence of surface water. Total annual precipitation
across the range of the lesser prairie-chicken varies, on average, from
roughly 63 cm (25 in) in the eastern portions of the historical range
to as little as 25 cm (10 in) in the western portions of the range.
Consequently, few sources of free-standing surface water existed in
lesser prairie-chicken historical range prior to settlement. Lesser
prairie-chickens likely rely on food sources and consumption of dew to
satisfy their metabolic moisture requirement (Snyder 1967, p. 123;
Hagen and Giesen 2005, unpaginated; Bidwell et al. 2002, p. 6) but will
use surface water when it is available. Because much of the
historically occupied range is now used for domestic livestock
production, numerous artificial sources of surface water, such as stock
ponds and stock tanks, have been developed throughout the region.
Several studies have documented use of these water sources by lesser
prairie-chickens during the spring, late summer, and fall seasons
(Copelin 1963, p. 20; Jones 1964, p. 70; Crawford and Bolen 1973, pp.
471-472; Crawford 1974, p. 41; Sell 1979, p. 31), and they may be
particularly important during periods of drought (Crawford and Bolen
1973, p. 472; Crawford 1974, p. 41). Hoffman (1963, p. 732) supported
development of supplemental water sources (i.e., guzzlers) as a
potential habitat improvement tool. Others, such as Davis et al. (1979,
pp. 127-128) and Applegate and Riley (1998, p. 15) cautioned that
creating additional surface water sources will influence grazing
pressure and possibly contribute to degradation of habitat conditions
for lesser prairie-chickens. Some livestock watering facilities may
create hazardous conditions (e.g., drowning; Sell 1979, p. 30), but the
frequency of these incidents is unknown.
Lesser prairie-chickens have a relatively short lifespan and high
annual mortality. Campbell (1972, p. 694) estimated a 5-year maximum
lifespan, although an individual nearly 7 years old has been documented
in the wild by the Sutton Avian Research Center (Sutton Center) (Wolfe
2010). Differences in survival may be associated with sex, weather,
harvest (where allowed), age, and habitat quality. Campbell (1972, p.
689), using 9 years of band recovery data from New Mexico, estimated
annual mortality for males to be 65 percent. Hagen et al. (2005, p. 82)
specifically examined survival in male lesser prairie-chickens in
Kansas and found apparent survival varied by year and declined with
age. Annual mortality was estimated to be 55 percent (Hagen et al.
2005, p. 83). Male survival may be lower during the breeding season due
to increased predation or costs associated with territorial defense
while lekking (Hagen et al. 2005, p. 83). In female lesser prairie-
chickens, Hagen et al. (2007, p. 522) estimated that annual mortality
in two remnant patches of native sand sagebrush prairie near Garden
City, Finney County, Kansas was about 50 percent at a study site
southwest of Garden City and about 65 percent at a study site southeast
of Garden City).
Adult annual survival in Texas apparently varied by habitat type.
In sand sagebrush habitat, survival was estimated to be 0.52, whereas
survival was only 0.31 in shinnery oak habitat (Lyons et al. 2009, p.
93). For both areas, survival was about 4 percent lower during the
breeding season than during the nonbreeding period (Lyons et al. 2009,
p. 93). Hagen et al. (2007, p. 522) also reported lower survival during
the reproductive season (31 percent mortality) compared to the
nonbreeding season (23 percent mortality) in Kansas. However, survival
times did not differ between sand sagebrush habitats in Oklahoma and
shinnery oak habitats in New Mexico (Patten et al. 2005a, p. 1274).
Birds occupying sites with greater than 20 percent shrub cover survived
longer than those in areas with less dense shrub cover (Patten et al.
2005a, p. 1275).
Habitat
The preferred habitat of the lesser prairie-chicken is native
short- and mixed-grass prairies having a shrub component dominated by
Artemesia filifolia (sand sagebrush) or Quercus havardii (shinnery oak)
(hereafter described as native rangeland) (Donaldson 1969, pp. 56, 62;
Taylor and Guthery 1980a, p. 6; Giesen 1998, pp. 3-4). Small shrubs are
important for summer shade (Copelin 1963, p. 37; Donaldson 1969, pp.
44-45, 62), winter protection, and as supplemental foods (Johnsgard
1979, p. 112). Historically, trees and other tall woody vegetation were
largely absent from these grassland ecosystems, except in canyons and
along water courses. Landscapes supporting less than 63 percent native
rangeland appear incapable of supporting self-sustaining lesser
prairie-chicken populations (Crawford and Bolen 1976a, p. 102).
Outside of the grasslands in Kansas, lesser prairie-chickens are
primarily found in the sand sagebrush dominated rangelands of Colorado,
Kansas, Oklahoma, and Texas, and in the shinnery oak-bluestem
grasslands of
[[Page 73844]]
New Mexico, Oklahoma, and Texas. Sand sagebrush is a 0.6- to 1.8-m (2-
to 6-ft) tall shrub that occurs in 11 States of the central and western
United States (Shultz 2006, p. 508). Within the central and southern
Great Plains, sand sagebrush is often a dominant species on sandy soils
and may exhibit a foliar cover of 20 to 50 percent (Collins et al.
1987, p. 94; Vermeire 2002, p. 1). Sand-sage shrublands have been
estimated to occupy some 4.8 million ha (11.8 million ac) in the
central and southern Great Plains (Berg 1994, p. 99).
The shinnery oak vegetation type is endemic to the southern great
plains and is estimated to have historically covered an area of 2.3
million ha (over 5.6 million ac), although its current range has been
considerably reduced through eradication (Mayes et al. 1998, p. 1609).
The distribution of shinnery oak overlaps much of the historical lesser
prairie-chicken range in New Mexico, Oklahoma, and Texas (Peterson and
Boyd 1998, p. 2). Shinnery oak is a rhizomatous (a horizontal, usually
underground stem that often sends out roots and shoots from its nodes)
shrub that reproduces slowly and does not invade previously unoccupied
areas (Dhillion et al. 1994, p. 52). Mayes et al. (1998, p. 1611)
documented that a single rhizomatous shinnery oak can occupy an area
exceeding 7,000 square meters (sq m) (75,300 square feet (sq ft)).
While not confirmed through extensive research throughout the plant's
range, it has been observed that shinnery oak in some areas multiplies
by slow rhizomatous spread and eventual fracturing of underground stems
from the original plant. In this way, single clones have been
documented to occupy up to 81 ha (200 ac) over an estimated timeframe
of 13,000 years (Cook 1985, p. 264; Anonymous 1997, p. 483), making
shinnery oak possibly the largest and longest-lived plant species in
the world.
Within the historical range of the species, the USDA's CRP,
administered by the Farm Services Administration, has promoted the
establishment and conservation of certain grassland habitats.
Originally funded as a mechanism to reduce erosion from highly erodible
soils, the program has since become a means to at least temporarily
retire any environmentally sensitive cropland from production and
establish vegetative cover on that land. Initially, many types of
grasses were approved for use as permanent vegetative cover, including
several that are introduced or nonnative. As the program changed and
efforts to establish more environmentally beneficial grasses gained
momentum, the use of native grasses became more prevalent. In Kansas in
particular, much of the vegetative cover established through the CRP
within the historical range of the lesser prairie-chicken was a mix of
native warm-season grasses such as Schizachyrium scoparium (little
bluestem), Bouteloua curtipendula (sideoats grama), and Panicum
virgatum (switchgrass) (Rodgers and Hoffman 2005, p. 120). These
grasses are important components of lesser prairie-chicken habitat and
have led to reoccupation of large areas of the historical range in
western Kansas by lesser prairie-chickens, particularly north of the
Arkansas River.
In other areas, nonnative grasses were used that provided limited
to no habitat value for the lesser prairie-chicken. Exotic old world
bluestems and Eragrostis curvula (weeping lovegrass) were extensively
seeded in CRP tracts in Texas, New Mexico, and Oklahoma (Haufler et al.
2012, p. 17). For example, about 70 to 80 percent of the original CRP
seedings in eastern New Mexico consisted of dense, single-species
stands of weeping lovegrass, Bothriochloa bladhii (Caucasian bluestem),
or B. ischaemum (yellow bluestem) (Rodgers and Hoffman 2005, p. 122).
Consequently these areas contributed very little to lesser prairie-
chicken conservation as they provide poor-quality nesting habitat. As
these nonnative grasslands have matured, some species of native grasses
and shrubs are beginning to reestablish within these fields. Although
these areas still have limited habitat value for lesser prairie-
chickens, the species is occasionally using these older stands of grass
for roosting and nesting (Rodgers and Hoffman 2005, p. 122). Where CRP
lands support the suitable vegetative structure and composition
required by lesser prairie-chickens, these fields can provide suitable,
but likely temporary, habitat. More information on the CRP program is
provided in the sections that follow.
Leks are characterized by areas of sparse vegetation and are
generally located on elevated features, such as ridges or grassy knolls
(Giesen 1998, p. 4). Vegetative cover characteristics, primarily height
and density, may have a greater influence on lek establishment than
elevation (Giesen 1998, p. 4). Copelin (1963, p. 26) observed display
grounds within short grass meadows of valleys where sand sagebrush was
tall and dense on the adjacent ridges. Early spring fires also
encouraged lek establishment when vegetation likely was too high (0.6
to 1.0 m (2.0 to 3.3 ft)) to facilitate displays (Cannon and Knopf
1979, pp. 44-45). Several authors, as discussed in Giesen (1998, p. 4),
observed that roads, oil and gas pads, and similar forms of human
disturbance create habitat conditions that may encourage lek
establishment. However, Taylor (1979, p. 707) emphasized that human
disturbance, which is often associated with these artificial lek sites,
is detrimental during the breeding season and did not encourage
construction of potential lek sites in areas subject to human
disturbance. Giesen (1998, p. 9) reported that hens usually nest and
rear broods within 3.4 km (1.7 mi) of leks and may return to nest in
areas of previously successful nests (Riley 1978, p. 36). Giesen
(1994a, pp. 97-98) and Hagen and Giesen (2005, unpaginated) also
reported that hens often nest closer to a lek other than the one on
which they mated.
Typical nesting habitat can be described as native rangeland,
although there is some evidence that the height and density of forbs
(broad-leaved herb other than a grass) and residual grasses is greater
at nesting locations than on adjacent rangeland (Giesen 1998, p. 9).
Nests are often located on north and northeast facing slopes as
protection from direct sunlight and the prevailing southwest winds
(Giesen 1998, p. 9). Giesen (1998, p. 9) reports that habitat used by
young is similar to that of adults, and the daily movement of the
broods is usually 300 m (984 ft) or less. After the broods break up,
the juveniles form mixed flocks with adult birds (Giesen 1998, p. 9),
and juvenile habitat use is similar to that of adult birds. Giesen
(1998, p. 4) reports that wintering habitat is similar to that used for
breeding with the exception that small grain fields are used more
heavily during this period than during the breeding season. Habitats
used by broods had greater total biomass of invertebrates and forb
cover than areas not frequented by broods in Kansas, emphasizing the
importance of forbs in providing the invertebrate populations used by
young lesser prairie-chickens (Jamison et al. 2002, pp. 520, 524).
Home range and dispersal distances of lesser prairie-chickens are
indicative of their requirement for large blocks of interconnected,
ecologically diverse native grassland. As reported by Giesen (1998, p.
11) and Taylor and Guthery (1980b, p. 522), a single lesser prairie-
chicken may have a home range (geographic area to which an organism
typically confines its activity) of 211 ha (512 ac) to 1,945 ha (4,806
ac). More recently, studies in Kansas demonstrated some birds may move
as much as 50 km (31 mi) from their point of capture (Hagen et al.
2004, p. 71). While some overlap in home ranges is
[[Page 73845]]
expected, rarely would those home ranges overlap completely due to
competition for space, food, and other resources. Taylor and Guthery
(1980a, p. 11) used lesser prairie-chicken movements in west Texas to
estimate the area needed to meet the minimum requirements of a lek
population. A contiguous area of suitable habitat encompassing at least
32 sq km (12 sq mi or 7,900 ac) would support about 90 percent of the
annual activity associated with a given lek and an area of 72 sq km (28
sq mi or 17,791 ac) would include all of the annual activity associated
with a lek except for some movements of juveniles (Taylor and Guthery
(1980a, p. 11). Bidwell et al. (2002. p. 3) conclude that at least
101.2 sq km (39 sq mi or 25,000 ac) of contiguous high-quality habitat
is needed to maintain a sustainable population of lesser prairie-
chickens. Because lesser prairie-chickens typically nest and rear their
broods in proximity to a lek other than the one used for mating (Giesen
1998, p. 9), a complex of two or more leks is likely the very minimum
required to sustain a viable lesser prairie-chicken population. Hagen
et al. (2004, p. 76) recommended that lesser prairie-chicken management
areas be at least 4,096 sq km (1,581 sq mi or 1,012,140 ac) in size.
Management areas of this size would incorporate the longest-known
movements of individual birds and be large enough to maintain healthy
lesser prairie-chicken populations despite the presence of potentially
large areas of unsuitable habitat.
Historical Range and Distribution
Prior to description by Ridgeway in 1885, most observers did not
differentiate between the lesser and greater prairie-chicken.
Consequently, estimating historical abundance and occupied range is
difficult. Historically, the lesser prairie-chicken is known to have
occupied native rangeland in portions of southeastern Colorado (Giesen
1994b, pp. 175-182), southwestern Kansas (Baker 1953, p. 9; Schwilling
1955, p. 10), western Oklahoma (Duck and Fletcher 1944, p. 68), the
Texas panhandle (Henika 1940, p. 15; Oberholser 1974, p. 268), and
eastern New Mexico (Ligon 1927, pp. 123-127).
Lesser prairie-chickens also have been documented from Nebraska,
based on at least four specimens known to have been collected near
Danbury in Red Willow County during the 1920s (Sharpe 1968, p. 50).
Sharpe (1968, pp. 51, 174) considered the occurrence of lesser prairie-
chickens in Nebraska to be the result of a short-lived range expansion
facilitated by settlement and cultivation of grain crops. Lesser
prairie-chickens are not currently believed to occur in Nebraska.
Sharpe did not report any confirmed observations since the 1920s
(Sharpe 1968, entire), and no sightings have been documented despite
searches over the last 5 years in southwestern Nebraska (Walker 2011).
Therefore, Nebraska is generally considered outside the historical
range of the species.
Based on a single source, Crawford (1974, p. 4) reported that the
lesser prairie-chicken was successfully introduced to the island of
Niihau in the State of Hawaii. Prairie-chickens were known to have been
released on Niihau, a privately owned island, in 1934 (Fisher 1951, p.
37), but the taxonomic identity of those birds has not ever been
confirmed. Schwartz and Schwartz (1949, p. 120) believed that these
birds were indeed lesser prairie-chickens. Fisher and members of his
expedition did observe at least eight individual prairie-chickens
during a visit to Niihau in 1947, but no specimens were collected due
to their scarcity and the landowner's requests (Fisher 1951, pp. 33-34,
37). Consequently, the specific identity of these birds could not be
confirmed, and their current status on the island remains unknown
(Pratt et al. 1987, p. 324; Pyle and Pyle 2009, p. 5). Similarly,
Jeschke and Strayer (2008, p. 127) indicate that both lesser and
greater prairie-chickens were introduced to parts of Europe, but both
species failed to become established there. Although we do not believe
that either greater or lesser prairie-chickens still persist in Hawaii
or Europe, we request that any recent information on the status of
lesser prairie-chickens in either Hawaii or Europe be provided to us
during the comment period.
Johnsgard (2002, p. 32) estimated the maximum historical range of
the lesser prairie-chicken to have encompassed some 260,000 to 388,500
sq km (100,000 to 150,000 sq mi), with about two-thirds of the
historical range occurring in Texas. Taylor and Guthery (1980a, p. 1,
based on Aldrich 1963, p. 537) estimated that, by the 1880s, the area
occupied by lesser prairie-chicken was about 358,000 sq km (138,225 sq
mi), and, by 1969, they estimated the occupied range had declined to
roughly 125,000 sq km (48,263 sq mi) due to widespread conversion of
native prairie to cultivated cropland. Taylor and Cuthery (1980a, p. 4)
estimated that, by 1980, the occupied range encompassed only 27,300 sq
km (10,541 sq mi), representing a 90 to 93 percent reduction in
occupied range since pre-European settlement and a 92 percent reduction
in the occupied range since the 1880s.
In 2007, cooperative mapping efforts by species experts from the
Colorado Parks and Wildlife (CPW) (formerly Colorado Division of
Wildlife), Kansas Department of Wildlife, Parks and Tourism (KDWPT)
(formerly Kansas Department of Wildlife and Parks), New Mexico
Department of Game and Fish (NMDGF), Oklahoma Department of Wildlife
Conservation (ODWC), and Texas Parks and Wildlife Department (TPWD), in
cooperation with the Playa Lakes Joint Venture, reestimated the maximum
historical and occupied ranges. They determined the maximum occupied
range, prior to European settlement, to have been approximately 456,087
sq km (176,096 sq mi) (Playa Lakes Joint Venture 2007, p. 1). The
approximate historical range, by State, based on this cooperative
mapping effort is the following: 21,911 sq km (8,460 sq mi) in
Colorado; 76,757 sq km (29,636 sq mi) in Kansas; 52,571 sq km (20,298
sq mi) in New Mexico; 68,452 sq km (26,430 sq mi) in Oklahoma; and
236,396 sq km (91,273 sq mi) in Texas. Since 2007, the CPW slightly
expanded the historical range in Colorado, based on new information.
The total maximum historically occupied range, based on this
adjustment, is now estimated to be about 466,998 sq km (180,309 sq mi).
Current Range and Distribution
The lesser prairie-chicken still occurs within the States of
Colorado, Kansas, New Mexico, Oklahoma, and Texas (Giesen 1998, p. 3).
During the 2007 mapping effort (Playa Lakes Joint Venture 2007, p. 1;
Davis et al. 2008, p 19), the State conservation agencies estimated the
current occupied range encompassed 65,012 sq km (25,101 sq mi). The
approximate occupied range, by State, based on this cooperative mapping
effort is 4,216 sq km (1,628 sq mi) in Colorado; 29,130 sq km (11,247
sq mi) in Kansas; 8,570 sq km (3,309 sq mi) in New Mexico; 10,969 sq km
(4,235 sq mi) in Oklahoma; and 12,126 sq km (4,682 sq mi) in Texas.
Since 2007, the occupied and historical range in Colorado and the
occupied range in Kansas have been adjusted to reflect new information.
The currently occupied range in Colorado is now estimated to be 4,456
sq km (1,720 sq mi), and, in Kansas, the lesser prairie-chicken is now
thought to occupy about 34,479 sq km (13,312 sq mi). In Kansas, the
adjustment was due to expansion of lesser prairie-chicken populations
in Ellis, Graham, Sheridan, and Trego Counties. The total estimated
occupied range is now believed to encompass
[[Page 73846]]
some 70,601 sq km (27,259 sq mi). The currently occupied range now
represents roughly 16 percent of the revised historical range. This
value is a close approximation because a small portion of the expanded
range in Kansas lies outside the estimated maximum historical range and
was not included in this analysis. Considering there are historical
records from Nebraska, the maximum historical range currently in use is
likely smaller than the maximum that would exist if the temporarily
occupied range in Nebraska was included in the analysis.
The overall distribution of lesser prairie-chicken within all
States except Kansas has declined sharply, and the species is generally
restricted to variously sized, often highly fragmented parcels of
untilled native rangeland (Taylor and Guthery 1980a, pp. 2-5) or areas
with significant CRP enrollments that were initially seeded with native
grasses (Rodgers and Hoffman 2005, pp. 122-123). The estimated current
occupied range, based on cooperative mapping efforts described above,
and as derived from calculations of the area of each mapped polygon
using geographical information software, represents about an 84 percent
reduction in overall occupied range since pre-European settlement.
Table 1--Estimated Historical and Current Occupied Lesser Prairie-Chicken Range by State
----------------------------------------------------------------------------------------------------------------
Extent
State Historical range Current range -----------------------------------------
Historical Current
----------------------------------------------------------------------------------------------------------------
Colorado....................... 6 counties........ 4 counties....... 21,910.9 sq km 4,216.5 sq km
(8,459.8 sq mi) (1,628.0 sq mi)
Kansas......................... 38 counties....... 35 counties...... 76,757.4 sq km 29,130.2 sq km
(29,636.2 sq mi) (11,247.2 sq mi)
New Mexico..................... 12 counties....... 7 counties....... 52,571.2 sq km 8,570.1 sq km
(20,297.9 sq mi) (3,308.9 sq mi)
Oklahoma....................... 22 counties....... 8 counties....... 68,452.1 sq km 10,969.1 sq km
(26,429.5 sq mi) (4,235.2 sq mi)
Texas.......................... 34 counties....... 13 counties *.... 236,396.2 sq km 12,126.5 sq km
(1940s-50s)....... (91,273.1 sq mi) (4,682.1 sq mi)
--------------------------------------------------------------------------------
TOTAL...................... 107 counties...... 67 counties...... 456,087.8 sq km 65,012.4 sq km
(176,096.5 sq mi) (25,101.4 sq mi)
----------------------------------------------------------------------------------------------------------------
* Timmer (2012, p. 36) only observed lesser prairie-chickens in 12 counties.
Population Estimates
Very little information is available regarding the size of lesser
prairie-chicken populations prior to 1900. Once the five States
supporting lesser prairie-chickens were officially opened for
settlement beginning in the late 1800s, settlement occurred quickly and
the landscape began to change rapidly. Numbers of lesser prairie-
chickens likely changed rapidly as well. Despite the lack of conclusive
information on population size, the lesser prairie-chicken was
reportedly quite common throughout its range in Colorado, Kansas, New
Mexico, Oklahoma, and Texas in the early twentieth century (Bent 1932,
pp. 280-281,283; Baker 1953, p. 8; Bailey and Niedrach 1965, p. 51;
Sands 1968, p. 454; Fleharty 1995, pp. 38-44; Robb and Schroeder 2005,
p. 13). Litton (1978, p. 1) suggested that as many as two million birds
may have occurred in Texas alone prior to 1900. By the 1930s, the
species had begun to disappear from areas where it had been considered
abundant, and the decline was attributed to extensive cultivation,
overgrazing by livestock, and drought (Bent 1932, p. 280). Populations
were nearly extirpated from Colorado, Kansas, and New Mexico, and were
markedly reduced in Oklahoma and Texas (Baker 1953, p. 8; Crawford
1980, p. 2).
Rangewide estimates of population size were almost nonexistent
until the 1960s and likely corresponded with more frequent and
consistent efforts by the States to monitor lesser prairie-chicken
populations. Although lesser prairie-chicken populations can fluctuate
considerably from year to year in response to variable weather and
habitat conditions, generally the overall population size has continued
to decline from the estimates of population size available in the early
1900s (Robb and Schroeder 2005, p. 13). By the mid-1960s, Johnsgard
(1973, p. 281) estimated the total rangewide population to be between
36,000 and 43,000 individuals. In 1980, the estimated rangewide fall
population size was thought to be between 44,400 and 52,900 birds
(Crawford 1980, p. 3). Population size in the fall is likely to be
larger than population estimates derived from spring counts due to
recruitment that occurs following the nesting season. By 2003, the
estimated total rangewide population was 32,000 birds, based on
information provided by the Lesser Prairie-Chicken Working Group (Rich
et al. 2004, unpaginated). Prior to the implementation of a rangewide
survey effort in 2012, the best available population estimates indicate
that the lesser prairie-chicken population likely would be
approximately 45,000 birds or less (see Table 2). This estimate is a
rough approximation of the maximum population size and should not be
considered as the actual current population size. Although the estimate
uses the most current information available, population estimates for
some States have not been determined in several years and reported
values may not represent actual population sizes. For example, the
values reported for Colorado and Oklahoma were published in 2000 and
recent estimates of total population size for these States have not
been determined. The aerial surveys conducted in 2012, as explained
below, provide the best estimate of current population size.
Table 2--Recent Population Estimates Prior to 2012 by State
------------------------------------------------------------------------
Recent population
State estimates prior to
2012
------------------------------------------------------------------------
Colorado........................................... <1,500 (in 2000)
Kansas............................................. 19,700-31,100
(in 2006)
New Mexico......................................... 6,130 (in 2011)
Oklahoma........................................... <3,000 (in 2000)
Texas.............................................. 1,254-2,649
(in 2010-11)
--------------------
TOTAL.......................................... <45,000
------------------------------------------------------------------------
[[Page 73847]]
In the spring (March 30 to May 3) of 2012, the States, in
conjunction with the Western Association of Fish and Wildlife Agencies,
implemented a rangewide sampling framework and survey methodology using
small aircraft. This aerial survey protocol was developed to provide a
more consistent approach for detecting rangewide trends in lesser
prairie-chicken population abundance across the occupied range. The
goal of this survey was to estimate the abundance of active leks and
provide information that could be used to detect trends in lek
abundance over time. The sampling framework used 15-by-15-km (9-by-9-
mi) grid cells overlapping the estimated occupied range, as existed in
2011, plus a 7.5-km (4.6-mi) buffer. Additional information on the
survey approach is provided in McDonald et al. 2011, entire. Another
survey is planned for the spring of 2013, provided funding is
available. We intend to incorporate those results, subject to
availability, into our final determination.
The aerial survey study area was divided into four regions that
encompassed the estimated occupied range of the lesser prairie-chicken.
These regions were delineated based on habitat type and results grouped
by individual State were not provided. The four regional groupings were
the Shinnery Oak Prairie Region of eastern New Mexico and southwest
Texas; the Sand Sagebrush Prairie Region located in southeastern
Colorado, southwestern Kansas, and western Oklahoma Panhandle; the
Mixed Grass Prairie Region located in the northeastern Texas panhandle,
northwestern Oklahoma, and south-central Kansas; and the Short Grass/
CRP Mosaic in northwestern Kansas and eastern Colorado. During surveys
of the 264 blocks selected, 40 lesser prairie-chicken leks, 6 mixed
leks comprised of both lesser and greater prairie-chickens, and 100
non-lek aggregations of lesser prairie-chickens were observed (McDonald
et al. 2012, p. 15). For this study, an active lek was defined as
having five or more birds per lek. If fewer than five individual birds
were observed, ground surveys were conducted of those bird groups to
determine if lekking birds were present. If not, those areas were
classified as ``non-leks''. After the survey observations were adjusted
to account for probability of detection, some 3,174 lesser prairie-
chicken leks were estimated to occur over the entire occupied range
(McDonald et al. 2012, p. 18). Another 441 mixed leks, consisting of
both lesser and greater prairie-chickens, were estimated to occur
within the occupied range. These mixed leks were limited to the Short
Grass/CRP Mosaic region where the range of the two species overlaps.
Using the respective average group size, by each identified region, an
estimate of the total number of lesser prairie-chickens and lesser/
greater prairie-chicken hybrids could be derived (McDonald et al. 2012,
p. 20). The total estimated abundance of lesser prairie-chickens was
37,170 individuals, with the number of hybrids estimated to be 309
birds (McDonald et al. 2012, p. 21). The estimated total number of
lesser prairie-chicken leks and population size, by habitat region, are
as follows: Shinnery Oak Prairie Region--428 leks and 3,699 birds; Sand
Sagebrush Prairie Region--105 leks and 1,299 birds; Mixed Grass Prairie
Region--877 leks and 8,444 birds; and the Short Grass/CRP Mosaic
Region--1,764 leks and 23,728 birds (McDonald et al. 2012, pp. 20, 23).
State-by-State Information on Population Status
Each of the State conservation agencies within the occupied range
of the lesser prairie-chicken provided us with information regarding
the current status of the lesser prairie-chicken within their
respective States, and most of the following information was taken
directly from agency reports, memos, and other status documents.
Population survey data are collected from spring lek surveys in the
form of one or both of the following indices: Average lek size (i.e.,
number of males or total birds per lek); or density of birds or leks
within a given area. Most typically, the data are collected along fixed
survey routes where the number of displaying males counted is assumed
to be proportional to the population size, or the number of leks
documented is assumed to be an index of population size or occupied
range. These techniques are useful in evaluating long-term trends and
determining occupancy and distribution but are very limited in their
usefulness for reliably estimating population size (Johnson and Rowland
2007, pp. 17-20). However, given existing constraints, such as
available staff and funding, they provide the best opportunity to
assess lesser prairie-chicken populations.
Although each State annually conducts lesser prairie-chicken
surveys according to standardized protocols, those protocols vary by
State. Thus, each State can provide information relative to lesser
prairie-chicken numbers and trends by State, but obtaining consistent
information across the entire range is difficult given the current
approach to population monitoring. However, in the absence of more
reliable estimators of bird density, total counts of active leks over
large areas were recommended as the most reliable trend index for
prairie grouse populations such as lesser prairie-chickens (Cannon and
Knopf 1981, p. 777; Hagen et al. 2004, p. 79). About 95 percent of the
currently estimated occupied range occurs on privately owned land, as
determined using the Protected Areas Database of the United States
hosted by the U.S. Geological Survey Gap Analysis Program. This
database describes land areas that are under public ownership and the
extent of private ownership can be determined by subtracting the amount
of public lands from the total land base encompassed by the occupied
range.
Colorado--Lesser prairie-chickens were likely resident in six
counties (Baca, Bent, Cheyenne, Kiowa, Kit Carson, and Prowers
Counties) in Colorado prior to European settlement (Giesen 2000, p.
140). At present, lesser prairie-chickens are known to occupy portions
of Baca, Cheyenne, Prowers, and Kiowa Counties, but are not known to
persist in Bent and Kit Carson Counties. Present delineated range
includes portions of eastern Lincoln County although breeding birds
have not been documented from this county. Populations in Kiowa and
Cheyenne Counties number fewer than 100 individuals and appear to be
isolated from other populations in Colorado and adjacent States (Giesen
2000, p. 144). The lesser prairie-chicken has been State-listed as
threatened in Colorado since 1973. Colorado Department of Wildlife (now
CPW) estimated 800 to 1,000 lesser prairie-chicken in the State in
1997. Giesen (2000, p. 137) estimated the population size, as of 2000,
to be fewer than 1,500 breeding individuals.
CPW has been monitoring leks annually since 1959, primarily by
using standard survey routes (Hoffman 1963, p. 729). A new survey
method was initiated in 2004, designed to cover a much broader range of
habitat types and a larger geographic area, particularly to include
lands enrolled in the CRP. The new methodology resulted in the
discovery of more leks and the documented use of CRP fields by lesser
prairie-chickens in Colorado. In 2011, CPW used aerial surveys in
addition to the more traditional ground surveys in an attempt to
identify new leks in Cheyenne County (Remington 2011).
A total count of 161 birds and 17 active leks were detected in 2011
(Verquer and Smith 2011, pp. 1-2). A lek is considered active when at
least three males are observed displaying on
[[Page 73848]]
the lek. There were six active leks in Baca County, nine active leks in
Prowers County, and two active leks in Cheyenne County. No active leks
were detected in Kiowa County although leks have been active in this
county as recently as 2008 (Verquer 2008, p. 1). No new active leks
were detected in Cheyenne County. Habitat provided by CRP continues to
be very important to persistence of birds in Prowers County.
Since 1977, the total number of birds observed during routine
survey efforts has varied from a high of 448 birds in 1990 to a low of
74 birds in 2007. The general population trajectory, based on number of
birds observed on active leks during the breeding season is declining,
excluding information from 1992 when limited survey data were
collected. The number of active leks remained fairly stable between
1999 and 2006. During this period, the highest number of active leks
recorded, 34, occurred in 2004 and again in 2006. The fewest number of
active leks observed occurred in 2002 when 24 leks were observed. The
average number of active leks observed between 1999 and 2006 was 30.1.
Beginning in 2007 and continuing to present, the number of active
leks observed has remained fairly stable. Since 2007, the highest
recorded number of active leks was 18, which occurred in 2007. The
fewest number of active leks observed was 13 recorded in 2009. The
average number of active leks over this period was 16.4, roughly half
of the average number of active leks (30) observed during the period
between 1999 and 2006. Drought conditions observed in 2006, followed by
severe winter weather, probably account for the decline in the number
of lesser prairie-chickens observed in 2007 (Verquer 2007, pp. 2-3). In
the winter of 2006-2007, heavy snowfall severely reduced food and cover
in Prowers, southern Kiowa, and most of Baca Counties for over 60 days.
Then, in the spring of 2008, nesting and brood rearing conditions were
unfavorable due to drought conditions in southeastern Colorado (Verquer
2009, p. 5).
As a complement to CPW surveys, counts are completed on the USFS
Comanche National Grassland in Baca County. On the Comanche National
Grassland, the estimated area occupied by the lesser prairie-chicken
over the past 20 years was approximately 27,373 ha (65,168 ac)
(Augustine 2005, p. 2). Surveys conducted during 1984 to 2005
identified 53 different leks on or immediately adjacent to USFS lands.
Leks were identified based on the presence of at least three birds on
the lek. Lek censuses conducted from 1980 to 2005 showed the number of
males counted per lek since 1989 has steadily declined (Augustine 2006,
p. 4). The corresponding population estimate, based on number of males
observed at leks, on the Comanche National Grassland was highest in
1988 with 348 birds and lowest in 2005 with approximately 64 birds and
only 8 active leks (Augustine 2006, p. 4). The estimate of males per
lek in 2005 declined more than 80 percent from that of 1988, from 174
males per lek to 32 males per lek, respectively. In 2009, each
historical lek was surveyed 2 to 3 times, and 4 active leks were
observed (Shively 2009b, p. 1). A high count of 25 males was observed
using these four leks. In the spring of 2008, five active leks and 34
birds were observed (Shively 2009a, p. 3).
Kansas--In the early part of the last century, lesser prairie-
chicken historical range included all or part of 38 counties, but by
1977, the species was known to exist in only 17 counties, all located
south of the Arkansas River (Waddell and Hanzlick 1978, pp. 22-23).
Since 1999, biologists have documented lesser prairie-chicken expansion
and reoccupation of 17 counties north of the Arkansas River, primarily
attributable to favorable habitat conditions (e.g., native grasslands)
created by implementation of the CRP in those counties. Currently,
lesser prairie-chickens occupy approximately 34,479 sq km (13,312 sq
mi) within all or portions of 35 counties in western Kansas. Greater
prairie-chickens in Kansas also have expanded their range, and, as a
result, mixed leks of both lesser prairie-chickens and greater prairie-
chickens occur within an overlap zone covering portions of 7 counties
(2,500 sq km (965 sq mi)) in western Kansas (Bain and Farley 2002, p.
684). Within this zone, apparent hybridization between lesser prairie-
chickens and greater prairie-chickens is now evident (Bain and Farley
2002, p. 684). Two survey routes used by KDWPT are located within this
overlap zone; however, hybrids have been observed on only one of those
routes. Although hybrid individuals are included in the counts, the
number of hybrids observed is typically less than 1 percent, or 2 to 7
birds, of the total number of birds observed on the surveyed areas.
Since inception of standard lesser prairie-chicken survey routes in
1967, the number of standard survey routes has gradually increased. The
number of standard routes currently surveyed in Kansas for lesser
prairie-chickens is 14 and encompasses an area of 627.5 sq km (242.3 sq
mi). Flush counts are taken twice at each lek located during the
standard survey routes. An estimated population density is calculated
for each route by taking the higher of the two flush counts, doubling
that count primarily to account for females, and then dividing the
estimated number of birds by the total area surveyed per route. The
current statewide trend in lesser prairie-chicken abundance between
2004 and 2009 indicates a declining population (Pitman 2011, p. 15).
In 2006, KDWPT estimated the breeding population of lesser prairie-
chickens in the State to be between 19,700 and 31,100 individuals
(Rodgers 2007a, p. 1). The total breeding population estimates were
derived using the National Gap Analysis Program, where the population
indices from each habitat type along 15 survey routes were extrapolated
for similar habitat types throughout total occupied lesser prairie-
chicken range statewide.
New Mexico--In the 1920s and 1930s, the former range of the lesser
prairie-chicken in New Mexico was described as all of the sand hill
rangeland of eastern New Mexico, from Texas to Colorado, and as far
west as Buchanan in DeBaca County. Ligon (1927, pp. 123-127) mapped the
breeding range at that time as encompassing portions of seven counties,
a small subset of what he described as former range. Ligon (1927, pp.
123-127) depicted the historical range in New Mexico as encompassing
all or portions of 12 counties. In the 1950s and 1960s, occupied range
was more extensive than the known occupied range in 1927 (Davis 2005,
p. 6), indicating reoccupation of some areas since the late 1920s.
Presently, the NMDGF reports that lesser prairie-chickens are known
from six counties (Chaves, Curry, DeBaca, Lea, Roosevelt and Quay
Counties) and suspected from one additional county (Eddy County). The
occupied range of the lesser prairie-chicken in New Mexico is
conservatively estimated to encompass approximately 5,698 sq km (2,200
sq mi) (Davis 2006, p. 7) compared with its historical range of 22,390
sq km (8,645 sq mi). Based on the cooperative mapping efforts conducted
by the Playa Lakes Joint Venture and the Lesser Prairie-Chicken
Interstate Working Group, occupied range in New Mexico was estimated to
be 8,570 sq km (3,309 sq mi), considerably larger than the conservative
estimate used by Davis (2006, p. 7). One possible reason for the
difference in occupied range is that Davis (2006, p. 7) did not
consider the known distribution to encompass any portion of Eddy County
or southern Lea County. Approximately 59 percent of the historical
lesser prairie-chicken
[[Page 73849]]
range in New Mexico is privately held, with the remaining historical
and occupied range occurring on lands managed by the BLM, USFS, and New
Mexico State Land Office (Davis 2005, p. 12).
In the 1950s, the lesser prairie-chicken population was estimated
at 40,000 to 50,000 individuals, but, by 1968, the population had
declined to an estimated 8,000 to 10,000 individuals (Sands 1968, p.
456). Johnsgard (2002, p. 51) estimated the number of lesser prairie-
chickens in New Mexico at fewer than 1,000 individuals by 2001.
Similarly, the Sutton Center estimated the New Mexico lesser prairie-
chicken population to number between 1,500 and 3,000 individuals, based
on observations made over a 7-year period (Wolfe 2008). Using lek
survey data, NMDGF currently estimates the statewide lesser prairie-
chicken population to be about 6,130 birds (Beauprez 2011, p. 22).
Based on the estimated population sizes in New Mexico since 2001, the
population appears to be increasing slightly (Beauprez 2011, p. 22).
Longer term trends are not available as roadside listening routes did
not become established until 1998. Prior to that date, counts were
conducted on some of the NMDGF Prairie-Chicken Areas or on lands under
the jurisdiction of the BLM. The current roadside survey uses 29
standard routes established since 1999, 10 additional routes
established in 2003 within the northeastern part of lesser prairie-
chicken historical range, and 41 routes randomly selected from within
the 382 townships located within the survey boundary.
Since initiating the 10 additional northeastern routes in 2003,
NMDGF reports that no leks have been detected in northeastern New
Mexico. Results provide strong evidence that lesser prairie-chickens no
longer occupy their historical range within Union, Harding, and
portions of northern Quay Counties (Beauprez 2009, p. 8). However, a
solitary male lesser prairie-chicken was observed and photographed in
northeastern New Mexico by a local wildlife law enforcement agent in
December 2007. Habitat in northeastern New Mexico appears capable of
supporting lesser prairie-chicken, but the lack of any known leks in
this region since 2003 suggests that lesser prairie-chicken populations
in northeastern New Mexico, if still present, are very small.
The core of occupied lesser prairie-chicken range in this State
lies in east-central New Mexico (Chaves, Curry, DeBaca, Lea, and
Roosevelt Counties). Populations in southeastern New Mexico, defined as
the area south of U.S. Highway 380, remain low and continue to decline.
The majority of historically occupied lesser prairie-chicken habitat in
southeastern New Mexico occurs primarily on BLM land. Snyder (1967, p.
121) suggested that this region is only marginally populated except
during favorable climatic periods. Best et al. (2003, p. 232) concluded
anthropogenic factors have, in part, rendered lesser prairie-chicken
habitat south of U.S. Highway 380 inhospitable for long-term survival
of lesser prairie-chickens in southeastern New Mexico. Similarly, NMDGF
suggests that habitat quality likely limits recovery of populations in
southeastern New Mexico (Beauprez 2009, p. 13).
The New Mexico State Game Commission owns and manages 29 Prairie-
chicken Areas ranging in size from 10 to 3,171 ha (29 to 7,800 ac)
within the core of occupied range in east central New Mexico. These
Prairie-chicken Areas total 109 sq km (42 sq mi), or roughly 1.6
percent of the total occupied lesser prairie-chicken range in New
Mexico. Instead of the typical roadside counts, the NMDGF conducts
``saturation'' surveys on each individual Prairie-chicken Area to
determine the presence of lesser prairie-chicken leks and individual
birds over the entire Prairie-chicken Area (Beauprez 2009, p. 7).
Adjacent lands are included within these surveys, including other State
Trust Lands, some adjacent BLM lands, and adjacent private lands. The
Prairie-chicken Areas are important to persistence of the lesser
prairie-chicken in New Mexico. However, considering the overall areal
extent of the Prairie-chicken Areas and that many Prairie-chicken Areas
are small and isolated, continued management of the surrounding private
and Federal lands is integral to viability of the lesser prairie-
chicken in New Mexico.
Oklahoma--Lesser prairie-chickens historically occurred in 22
Oklahoma counties. By 1961, Copelin (1963, p. 53) reported lesser
prairie-chickens from only 12 counties. By 1979, lesser prairie-
chickens were verified in eight counties, and the remaining population
fragments encompassed an estimated area totaling 2,792 sq km (1,078 sq
mi), a decrease of approximately 72 percent since 1944. At present, the
ODWC reports lesser prairie-chickens continue to persist in eight
counties with an estimated occupied range of approximately 950 sq km
(367 sq mi). Horton (2000, p. 189) estimated the entire Oklahoma lesser
prairie-chicken population numbered fewer than 3,000 birds in 2000. A
more recent estimate has not been conducted.
The ODWC is aware of 96 known historical and currently active leks
in Oklahoma. During the mid-1990s, all of these leks were active.
Survey efforts to document the number of active leks over the occupied
range have recently been completed, but the results are currently
unavailable.
The number of roadside listening routes currently surveyed annually
in Oklahoma has varied from five to seven over the last 20 years, and
counts of the number of males per lek have been conducted since 1968.
Beginning with the 2002 survey, male counts at leks were replaced with
flush counts, which did not differentiate between the sexes of birds
flushed from the surveyed lek (ODWC 2007, pp. 2, 6). Comparing the
total number of males observed during survey efforts between the years
1977 through 2001 reveals a declining trend. However, examination of
the overall density of leks (number per sq mi), another means of
evaluating population status of lesser prairie-chickens, over five of
the standard routes since 1985 is stable to slightly declining.
Information on lek density prior to 1985 was unavailable. The standard
route in Roger Mills County was not included in this analysis because
the lek was rarely active and has not been surveyed since 1994. A
survey route in Woods County was included in the analysis even though
surveys on this route did not begin until 2001. However, excluding the
Woods County route did not alter the apparent trend. The average lek
density since 2001 is 0.068 leks per sq mi (Schoeling 2010, p. 3).
Between 1985 and 2000, the average lek density was 0.185 leks per sq
mi, when the route in Roger Mills County is excluded from the analysis.
Over the last 10 years, the density of active leks has varied from a
low of 0.02 leks per sq km (0.05 leks per sq mi) in 2004, 2006, and
2009, to a high of 0.03 leks per sq km (0.09 leks per sq mi) in 2005
and 2007 (Schoeling 2010, p. 3).
Texas--Systematic surveys to identify Texas counties inhabited by
lesser prairie-chickens began in 1940 (Henika 1940, p. 4). From the
early 1940s (Henika 1940, p. 15; Sullivan et al. 2000) to mid-1940s
(Litton 1978, pp. 11-12), to the early 1950s (Seyffert 2001, pp. 108-
112), the range of the lesser prairie-chicken in Texas was estimated to
encompass all or portions of 34 counties. Species experts considered
the occupied range at that time to be a reduction from the
presettlement range. By 1989, TPWD estimated occupied range encompassed
all or portions of only 12 counties (Sullivan et al. 2000, p. 179). In
2005, TPWD reported that the number of
[[Page 73850]]
occupied counties likely has not changed since the 1989 estimate. In
March 2007, TPWD reported that lesser prairie-chickens were confirmed
from portions of 13 counties (Ochiltree, Lipscomb, Roberts, Hemphill,
Gray, Wheeler, Donley, Bailey, Lamb, Cochran, Hockley, Yoakum, and
Terry Counties) and suspected in portions of another eight counties
(Moore, Carson, Oldham, Deaf Smith, Randall, Swisher, Gaines, and
Andrews Counties).
Based on recent aerial and road surveys conducted in 2010 and 2011,
new leks were detected in Bailey, Cochran, Ochiltree, Roberts, and
Yoakum Counties, expanding the estimated occupied ranges in those
counties (TPWD 2011). However, no lesser prairie-chickens were detected
in Andrews, Carson, Deaf Smith, Oldham, or Randall Counties. Active
leks were reported from the same 13 counties identified in 2007.
However, in 2012, Timmer (2012, pp. 36, 125-131) only observed lesser
prairie-chickens from 12 counties: Bailey, Cochran, Deaf Smith, Donley,
Gray, Hemphill, Lipscomb, Ochiltree, Roberts, Terry, Wheeler, and
Yoakum. Lesser prairie-chicken populations in Texas primarily persist
in two disjunctive regions--the Permian Basin/Western Panhandle region
and the Northeastern Panhandle region.
Maximum occupied range in Texas, as of September 2007, was
estimated to be 12,787 sq km (4,937.1 sq mi), based on habitat
conditions in 20 panhandle counties (Davis et al. 2008, p. 23).
Conservatively, based on those portions of the 13 counties where lesser
prairie-chickens are known to persist, the area occupied by lesser
prairie-chickens in Texas is 7,234.2 sq km (2,793.1 sq mi). Using an
estimated mean density of 0.0088 lesser prairie-chickens per ac (range
0.0034-0.0135 lesser prairie-chickens per ac), the Texas population is
estimated at a mean of 15,730 individuals in the 13 counties where
lesser prairie-chickens are known to occur (Davis et al. 2008, p. 24).
Since 2007, Texas has been evaluating the usefulness of aerial
surveys as a means of detecting leks and counting the number of birds
attending the identified lek (McRoberts 2009, pp. 9-10). Initial
efforts focused on measuring lek detectability and assessing the
response of lekking birds to disturbance from survey aircraft. More
recently, scientists at Texas Tech University used aerial surveys to
estimate the density of lesser prairie-chicken leks and statewide
abundance of lesser prairie-chickens in Texas. This study conducted an
inventory of 208 survey blocks measuring 7.2 by 7.2 km (4.5 by 4.5 mi),
encompassing some 87 percent of the occupied range in Texas during the
spring of 2010 and 2011 (Timmer 2012, pp. 26-27, 33). Timmer (2012, p.
34) estimated 2.0 leks per 100 sq km (0.02 leks per sq km). Previously
reported estimates of rangewide average lek density varied from 0.10 to
0.43 leks per sq km (Davison 1940, Sell 1979, Giesen 1991, Locke 1992
as cited in Hagen and Giesen 2005, unpaginated). The total estimate of
the number of leks was 293.6 and, based on the estimated number of
birds observed using leks, the statewide population was determined to
be 1,822.4 lesser prairie-chickens (Timmer 2012, p. 34).
Recent Trends
In June 2012, we were provided with an interim assessment of lesser
prairie-chicken population trends since 1997 (Hagen 2012, entire). The
objective of this analysis was to provide an evaluation of recent
lesser prairie-chicken population trends both rangewide and within the
four primary habitat types (CRP-shortgrass prairie dominated landscape,
mixed grass prairie landscape, sand sagebrush prairie landscape, and
shinnery oak landscape) that encompass the occupied range of the
species. The analysis employed modeling techniques intended to provide
a more unified assessment of population trends, considering that each
State uses slightly different methods to monitor lesser prairie-
chickens and that sampling effort has varied over time, with sampling
efforts typically increasing in recent years. The results of this
analysis suggest that lesser prairie-chicken population trends have
increased since 1997.
However, we are reluctant to place considerable weight on this
interim assessment for several reasons. First, and perhaps most
important, is that the analysis we were provided is a preliminary
product. We anticipate that a more complete, and perhaps peer-reviewed,
product would be submitted during the comment period on this proposed
rule. Second, we have concerns with the differences in how lek counts
are conducted and how those differences were addressed. For example,
when the States conduct flush counts at the leks, all of the States,
except Oklahoma, count the number of males flushed from the lek.
However, since 1999, Oklahoma has counted all birds flushed from the
lek and did not differentiate between males and females. Additionally,
some of the States use numbers derived from lek counts conducted over
large areas rather than road side listening routes. We are unsure how
these differences in sampling methodology would influence the pooled
trend information presented, particularly for large geographical areas
where two different sampling methods are used in the analysis. Third,
the trend information presents only information gathered since 1997 or
more recently, without considering historical survey information. The
trends evident from sampling efforts since 1997 likely reflect
increased sampling effort following publication of the 12-month
finding, and increased sampling effort could lead to biased results. In
some instances, sampling methodology by agency likely varied between
years during this time period as access to some study areas was
restricted and new areas were established in their place. For example,
in southwest Texas, two study areas were used until 1999, when an
additional sampling area in Yoakum County was added. Then in 2007, the
original Gaines County study area was dropped and a new, smaller Gaines
County study area was established to replace the original study area.
Similar changes occurred in the northeastern panhandle of Texas where a
new study area in Gray County was added in 1998. These changes in
sampling location can confound efforts to make comparisons between
years. An explanation regarding how these changes were addressed in the
assessment would be helpful.
We also recognize the limitations of using lek counts to derive
population trends over large areas (see Johnson and Rowland 2007, pp.
17-20). Consequently, we cautioned against using available data from
lek counts to derive rangewide population trends for similar reasons.
Such analyses can be misleading. However, information on historical and
recent lesser prairie-chicken population trends over large geographical
areas would improve our analysis of the status of the species and we
support efforts to provide a reliable, accurate analysis of rangewide
population trends, particularly if those analytical methods are
repeatable over time.
Summary of Status Information
Lesser prairie-chicken populations are distributed over a
relatively large area, and these populations can fluctuate considerably
from year to year, a natural response to variable weather and habitat
conditions. Changes in lesser prairie-chicken breeding populations may
be indicated by a change in the number of birds attending a lek (lek
size), the number of active leks, or both. Although each State conducts
standard surveys for lesser prairie-chickens, the application of survey
methods and effort
[[Page 73851]]
varies by State. Such factors complicate interpretation of population
indices for the lesser prairie-chicken and may not reliably represent
actual populations. Caution should be used in evaluating population
trajectories, particularly short-term trends. In some instances, short-
term analyses could reveal statistically significant changes from one
year to the next but actually represent a stable population when
evaluated over longer periods of time. For example, increased
attendance of males at leks may be evident while the number of active
leks actually declined. Some recent survey indices indicate that
population trends might be stabilizing. However, the numbers of lesser
prairie-chickens reported per lek are considerably less than the
numbers of birds reported during the 1970s. Population indices appear
to have exhibited a steeper decline during these earlier periods than
is apparent in recent years. Observed lek attendance at many leks is
low, likely due to reduced population sizes. Where lek attendance is
low, it is unlikely that populations will recover to historical levels.
Estimates of historical population size also can be unreliable and lead
to inaccurate inferences about the populations of interest. However,
the loss and alteration, including fragmentation, of lesser prairie-
chicken habitat throughout its historical range over the past several
decades is apparent and likely is more indicative of the status of the
lesser prairie-chicken.
Summary of Factors Affecting the Species
The Act defines an endangered species as any species that is ``in
danger of extinction throughout all or a significant portion of its
range'' and a threatened species as any species ``that is likely to
become endangered throughout all or a significant portion of its range
within the foreseeable future.'' Thus, a species may be listed as a
threatened species if it is likely to qualify for endangered status in
the foreseeable future, or in other words, likely to become ``in danger
of extinction'' within the foreseeable future. The Act does not define
the term ``foreseeable future.'' However, in a January 16, 2009,
memorandum addressed to the Acting Director of the Service, the Office
of the Solicitor, Department of the Interior, concluded, ``* * * as
used in the [Act], Congress intended the term `foreseeable future' to
describe the extent to which the Secretary can reasonably rely on
predictions about the future in making determinations about the future
conservation status of the species (M-37021, January 16, 2009).''
In considering the foreseeable future as it relates to the status
of the lesser prairie-chicken, we considered the factors acting on the
species and looked to see if reliable predictions about the status of
the species in response to those factors could be drawn. We considered
the historical data to identify any relevant existing trends that might
allow for reliable prediction of the future (in the form of
extrapolating the trends). We also considered whether we could reliably
predict any future events that might affect the status of the species,
recognizing that our ability to make reliable predictions into the
future is limited by the variable quantity and quality of available
data.
Under section 4(a)(1) of the Act, we determine whether a species is
an endangered or threatened species because of any of the following
five factors: (A) The present or threatened destruction, modification,
or curtailment of its habitat or range; (B) overutilization for
commercial, recreational, scientific, or educational purposes; (C)
disease or predation; (D) the inadequacy of existing regulatory
mechanisms; and (E) other natural or manmade factors affecting its
continued existence. Listing actions may be warranted based on any of
the above threat factors, singly or in combination.
After a review of the best available scientific information as it
relates to the status of the species and the five listing factors
described above, we have determined that the lesser prairie-chicken
meets the definition of a threatened species (i.e., is likely to become
in danger of extinction in the foreseeable future throughout all or a
significant portion of its range). Following, we present a very brief
explanation of the rationale leading to this conclusion followed by an
in-depth discussion of the best available scientific information.
The range of the lesser prairie-chicken has been reduced by an
estimated 84 percent (see discussion above in ``Current Range and
Distribution''). The primary factor responsible for the range
contraction is habitat fragmentation due to a variety of mechanisms
that contribute to habitat loss and alteration. This habitat loss is a
significant threat to the lesser prairie-chicken because the species
requires large parcels of intact native grassland and shrubland to
maintain self-sustaining populations. Further, the life history of the
species, primarily its lek breeding system and behavioral avoidance of
vertical structures that increase predation risk, make it especially
vulnerable to ongoing impacts on the landscape, especially at its
currently reduced numbers. Finally, due to its reduced population size
and ongoing habitat loss and degradation, the species lacks sufficient
redundancy and resiliency to recover from present and future impacts.
While the current status of the lesser prairie-chicken has been
substantially compromised by historical and current threats, there
appear to be sufficient stable populations to ensure the persistence of
the species over the near term. Therefore, as a result of continued
population declines predicted into the foreseeable future, the species
is likely to become in danger of extinction in the foreseeable future.
Following, we present our analysis of the best available
information that has led us to this conclusion.
Habitat Fragmentation
Spatial habitat fragmentation occurs when some form of disturbance,
usually habitat alteration or loss, results in the separation or
splitting apart of larger, previously contiguous, functional components
of habitat into smaller, often less valuable, noncontiguous parcels
(Wilcove et al. 1986, p. 237; Johnson and Igl 2001, p. 25; Franklin et
al. 2002, entire). Fragmentation influences habitat availability in
three primary ways: total area of available habitat; size of habitat
patches, including edge effects; and patch isolation (Johnson and Igl
2001, p. 25; Stephens et al. 2003, p. 101). Initially, reduction in the
total area of available habitat (i.e., habitat loss) may be more
significant than fragmentation and can exert a much greater effect of
extinction (Fahrig (1997, pp. 607, 609). However, as habitat loss
continues, the effects of fragmentation often compound effects of
habitat loss and produce even greater population declines than habitat
loss alone (Bender et al. 1998, pp. 517-518, 525). At the point where
some or all of the remaining habitat fragments or patches are below
some minimum required size, the impact of additional habitat loss, when
it consists of inadequately sized parcels, is minimal (Herkert 1994, p.
467). In essence, once a block of suitable habitat becomes so
fragmented that the size of the remaining patches become biologically
unsuitable, further habitat loss, when it consists of these unusable
patches, is of little further consequence to the organism (Bender et
al. 1998, p. 525).
Both habitat loss and fragmentation correlate with an ecological
concept known as carrying capacity. Within any given block or patch of
habitat, carrying capacity is the maximum number of organisms that can
be supported
[[Page 73852]]
indefinitely within that area, provided sufficient food, space, water,
and other necessities are available, without causing degradation of the
habitat within that patch. Theoretically, as habitat loss increases and
the size of an area shrinks, the maximum number of individuals that
could inhabit that particular habitat patch also would decline.
Consequently, a reduction in the total area of available habitat can
negatively influence biologically important characteristics such as the
amount of space available for establishing territories and nest sites
(Fahrig 1997, p. 603). Over time, the continued conversion and loss of
habitats to other land uses will reduce the ability of the land to
support historical population levels, causing a decline in population
sizes. Where the ability to effect restoration of these habitats is
lost, the observed reduction in fish or wildlife populations is likely
to be permanent. Within the United States, habitat loss and degradation
were found to have contributed to the endangerment of 85 percent of the
species listed either as imperiled by The Nature Conservancy or
protected under the Act, at the time of their study (Wilcove et al.
1998, p. 609).
Fragmentation not only contributes to overall habitat loss but also
causes a reduction in the size of individual habitat patches and
influences the proximity of these patches to other patches of similar
habitat (Stephens et al. 2003, p. 101; Fletcher 2005, p. 342). Habitat
quality within a fragment may decline as the size of the fragment
declines, particularly where habitat quality is a function of fragment
size (Franklin et al. 2002, p. 23). Fahrig and Merriam (1994, p. 53)
reported that both the size and shape of the fragment have been shown
to influence population persistence. The size of the fragment can
influence reproductive success, survival, and movements. As the
distance between habitat fragments increases, dispersal between the
habitat patches may cease, impacting population persistence and perhaps
even leading to both localized and regional extinctions (Harrison and
Bruna 1999, p. 226; With et al. 2008, p. 3153).
The proportion of habitat edge to interior habitat increases as the
size of a fragment declines. The edge is the transition zone between
the original habitat type and the land use that caused fragmentation of
the original parcel. In contrast, the core is the area within a
fragment that remains intact and is largely or completely uninfluenced
by the margin or edge of the fragment. Edge habitat proliferates with
increasing fragmentation (Sisk and Battin 2002, p. 31). The response of
individual species to the presence of edges varies markedly depending
on their tolerance to the edge and the nature of its effects (Sisk and
Battin 2002, p. 38). The effects often depend on the degree of contrast
between the habitat edge and the adjacent land use matrix. The
transition can be abrupt or something more gradual and less harsh. Most
typically, edges have been documented to influence movements and
survival, particularly for species that use interior or core habitats,
serve as points of entry for predators and parasites (such as presence
of fences adjacent to grasslands which provide hunting perches for
avian predators), alter microclimates, subsidize feeding opportunities
(such as providing access to waste grains in cropland areas), and
influence species interactions, particularly with cosmopolitan species
that tend to be habitat generalists (Sisk and Battin 2002, p. 38).
Fragmentation also can influence the heterogeneity or variation
within the resulting fragment. Heterogeneity, in turn, influences the
quality of the habitat within the fragment, with more homogeneous
fragments generally being less valuable. Grasslands tend to be
structurally simple and have little vertical layering. Instead, habitat
heterogeneity tends to be largely expressed horizontally rather than
vertically (Wiens 1974b, pp. 195-196). Prior to European settlement,
the interaction of grazing by wild ungulates and fire created a
shifting mosaic of vegetative patches having various composition and
structure (Pillsbury et al. 2011, p. 2). Under these conditions, many
grassland birds distribute their behavioral activities unevenly
throughout their territories by nesting in one area, displaying in
another, and foraging in still others (Wiens 1974b, p. 208). Lesser
prairie-chickens exhibit this pattern and cue in on specific vegetation
structure and microenvironment features depending on the specific phase
of their life cycle. Consequently, blocks of habitat that collectively
or individually encompass multiple successional states that comprise
tall grasses and shrubs needed for nesting, and are in proximity to
more open grasslands supporting forbs for brood rearing, and are
combined with smaller areas of short grass and bare ground used for
breeding, support all of the habitat types used by lesser prairie-
chickens throughout the year. Considering habitat diversity tends to be
greater in larger patches, finding the appropriate mosaic of these
features is more likely in larger fragments rather than smaller
fragments (Helzer and Jelinski 1999, p. 1456). Such habitat
heterogeneity is very different from habitat fragmentation. Habitat
fragmentation occurs when the matrix separating the resulting fragments
is converted to a use that is not considered habitat whereas habitat
heterogeneity implies that patches each having different vegetative
structure exist within the same contiguous block of habitat. Habitat
heterogeneity may influence habitat quality, but it does not represent
fragmentation (Franklin et al. 2002, p. 23).
Isolation is another factor that influences suitability of habitat
fragments. As habitat loss continues to progress over time, the
remnants not only become smaller and more fragmented, they become more
isolated from each other. When habitat patches become more isolated and
the amount of unusable, unsuitable land use surrounding the islands of
habitat increases, even patches of suitable quality and size may no
longer be occupied. As fragmentation progresses, the ability of
available dispersers to locate suitable fragments will decline. At some
point, the amount of intervening unusable and unsuitable land
comprising the matrix between the patches grows so wide that it exceeds
the organism's dispersal capabilities, rendering the matrix impermeable
to dispersal. In such instances, colonizers are unavailable to occupy
the otherwise suitable habitat and reestablish connectivity. These
patches may remain vacant indefinitely. While extinctions at the local
level, and subsequent recolonization of the vacant patch, are common
phenomena, recolonization depends on the availability of dispersing
individuals and their ability to disperse within the broader landscape
(Fahrig and Merriam 1994, p. 52). When the number of individuals at the
landscape or regional level that are available to disperse declines,
the overall population begins to decline and will, in turn, affect the
number of individuals available to disperse. Connectivity between
habitat patches is one means of facilitating dispersal, but the
appropriate size or configuration of the dispersal corridors needed to
facilitate connectivity for many species is unknown.
Causes of Habitat Fragmentation Within Lesser Prairie-Chicken Range
A number of factors can cause or contribute to habitat
fragmentation. Generally, fragmentation can result from the direct loss
or alteration of habitat due to conversion to other land uses or
[[Page 73853]]
from habitat alteration which indirectly leaves the habitat in such a
condition that the remaining habitat no longer functionally provides
the preferred life-history requisite. Functional habitat impacts can
include disturbances that alter the existing successional state of a
given area, create a physical barrier that precludes use of otherwise
suitable areas, or triggers a behavioral response by the organism such
that otherwise suitable habitats are abandoned or no longer used.
Fragmentation tends to be most significant when human developments are
dispersed across the landscape rather than being concentrated in fewer
areas. Anthropogenic causes of fragmentation tend to be more
significant than natural causes because the organism has likely evolved
in concert with the natural causes.
Initially, settlement and associated land use changes had the
greatest influence on fragmentation in the Great Plains. Knopf (1994,
p. 249) identified four universal changes that occurred in Great Plains
grasslands postsettlement, based on an evaluation of observations made
by early explorers. These changes were identified as a change in the
native grazing community, cultivation, wetland conversion, and
encroachment of woody vegetation.
EuroAmerican settlement of much of the Great Plains began in
earnest with passage of the Homestead Act of 1862. Continued settlement
and agricultural development of the Great Plains during the late 1800s
and early 1900s clearly contributed to conversion and fragmentation of
once open native prairies into a mosaic of varied land uses such as
cultivated cropland, expanding cedar woodlands, and remnants of
grassland (NRCS 1999, p. 1; Coppedge et al. 2001, p. 47; Brennan and
Kuvlesky 2005, pp. 2-3). Changes in agricultural practices and
advancement of modern machinery combined with an increasing demand for
agricultural products continued to spur conversion of native prairies
well into the mid-1900s (NRCS 1999, p. 2). Increasing human population
densities in rural areas of the Great Plains led to construction of
housing developments as growing cities began to expand into the
surrounding suburban landscapes. Development and intensification of
unsuitable land uses in these urbanizing landscapes also contributed to
conversion and fragmentation of grasslands, further reducing richness
and abundance of avian populations (Perlut et al. 2008, p. 3149; Hansen
et al. 2011, p. 826). See the section on settlement below for related
discussion.
Oil and gas development also began during the mid to late 1800s.
Eventually, invention of the automobile in the early twentieth century
and its rise to prominence as the primary mode of personal
transportation stimulated increased exploration and development of oil
and gas (Hymel and Wolfsong 2006, p. 4). Habitat loss and fragmentation
associated with access roads, drill pads, pipelines, waste pits, and
other components typically connected with exploration and extraction of
oil and gas are considered to be among the most significant ecological
impacts from oil and gas development and the impacts often extend
beyond the actual physical structures (Weller et al. 2002, p. 2). See
the section on energy development below for related discussion.
As human populations continued to expand outside of existing
suburban areas, particularly into rural regions, an increasing array of
human features such as powerlines, highways, secondary roads,
communication towers, and other types of infrastructure necessary to
support these human populations appeared on the landscape (Leu et al.
2008, p. 1119). Often these developments can degrade ecosystem
functions and lead to fragmentation even when the overall development
footprint is relatively small.
Recent research demonstrates that natural vertical features like
trees and artificial, above ground vertical structures such as power
poles, fence posts, oil and gas wells, towers, and similar developments
can cause general habitat avoidance and displacement in lesser prairie-
chickens and other prairie grouse (Anderson 1969, entire; Robel 2002,
entire; Robel et al. 2004, entire; Hagen et al. 2004, entire; Pitman et
al. 2005, entire; Pruett et al. 2009a, entire; Hagen et al. 2011
entire). This avoidance behavior is presumably a behavioral response
that serves to limit exposure to predation. The observed avoidance
distances can be much larger than the actual footprint of the structure
and appear to vary depending upon the type of structure. These
structures can have significant negative impacts by contributing to
further fragmentation of otherwise suitable habitats.
Prairie grouse, like the lesser prairie-chicken, did not evolve
with tall, vertical structures present on the landscape and, in
general, have low tolerance for tall structures. As discussed in
``Altered Fire Regimes and Encroachment by Invasive Woody Plants''
below, encroachment of trees into native grasslands preferred by lesser
prairie-chickens ultimately renders otherwise suitable habitat
unsuitable unless steps are taken to remove these trees. Even
artificially erected trees can cause an avoidance response. Anderson
(1969, pp. 640-641) observed that greater prairie-chickens abandoned
lek territories when a 4-m (13-ft) tall coniferous wind break was
artificially erected 52 m (170 ft) from an active lek.
Increasingly, artificial vertical structures are appearing in
landscapes used by lesser prairie-chickens. The placement of these
vertical structures in open grasslands represents a significant change
in the species' environment and is a relatively new phenomenon over the
evolutionary history of this species. The effects of these structures
on the life history of prairie grouse are only beginning to be
evaluated, with similar avoidance behaviors also having been observed
in sage grouse (75 FR 13910, March 23, 2010).
Robel (2002, p. 23) reported that a single commercial-scale wind
turbine creates a habitat avoidance zone for the greater prairie-
chicken that extends as far as 1.6 km (1 mi) from the structure. Lesser
prairie-chickens likely exhibit a similar response to tall structures
like wind turbines (Pitman et al. 2005, pp. 1267-1268). The Lesser
Prairie-Chicken Interstate Working Group identified the need for a
contiguous block of 52 sq km (20 sq mi) of high-quality rangeland
habitat to successfully maintain a local population of lesser prairie-
chicken; based on this need and the fact that the majority of remaining
populations are fragmented and isolated into islands of unfragmented,
open prairie habitat, the Service recommended that an 8-km (5-mi)
voluntary no-construction buffer be established around prairie grouse
leks to account for behavioral avoidance and to protect lesser prairie-
chicken populations and habitat corridors needed for future recovery
(Manville 2004, pp. 3-4). No lesser prairie-chickens were observed
nesting or lekking within 0.8 km (0.5 mi) of a gas line compressor
station, and otherwise suitable habitat was avoided within a 1.6-km (1-
mi) radius of a coal-fired power plant (Pitman et al. 2005, pp. 1267-
1268). Pitman et al. (2005, pp. 1267-1268) also observed that female
lesser prairie-chickens selected nest sites that were significantly
further from powerlines, roads, buildings, and oil and gas wellheads
than would be expected at random. Specifically, they observed that
lesser prairie-chickens seldom nested or reared broods within
approximately 177 m (580 ft) of oil or gas wellheads, 400 m (1,312 ft)
of electrical transmission lines, 792 m (2,600 ft) of improved roads,
and 1,219 m (4,000 ft) of buildings; and, the
[[Page 73854]]
observed avoidance was likely influenced, at least in part, by
disturbances such as noise and visual obstruction associated with these
features. Similarly, Hagen et al (2004, p. 75) indicated that areas
used by lesser prairie-chickens were significantly further from these
same types of features than areas that were not used by lesser prairie-
chickens. They concluded that the observed avoidance was likely due to
potential for increased predation by raptors or due to presence of
visual obstructions on the landscape (Hagen et al. 2004, pp. 74-75).
Robel et al. (2004, pp. 256-262) determined that habitat
displacement associated with avoidance of certain structures by lesser
prairie-chickens can be substantial, collectively exceeding 21,000 ha
(53,000 ac) in a three-county area of southwestern Kansas. Using
information on existing oil and gas wells, major powerlines (115 kV and
larger), and existing wind turbines and proposed wind energy
development in northwestern Oklahoma, Dusang (2011, p. 61) modeled the
effect of these anthropogenic structures on lesser prairie-chicken
habitat in Oklahoma. He estimated that existing and proposed
development of these structures potentially would eliminate some
960,917 ha (2,374,468 ac) of nesting habitat for lesser prairie-
chickens, based on what is currently known about their avoidance of
these structures.
Avoidance of vertical features such as trees and transmission lines
likely is due to frequent use of these structures as hunting perches by
birds of prey (Hagen et al. 2011, p. 72). Raptors actively seek out and
use power poles and similar aboveground structures in expansive
grassland areas where natural perches are limited. In typical lesser
prairie-chicken habitat where vegetation is low and the terrain is
relatively flat, power lines and power poles provide attractive
hunting, loafing, and roosting perches for many species of raptors
(Steenhof et al. 1993, p. 27). The elevated advantage of transmission
lines and power poles serve to increase a raptor's range of vision,
allow for greater speed during attacks on prey, and serve as
territorial markers. While the effect of avian predation on lesser
prairie-chickens undoubtedly depends on raptor densities, as the number
of perches or nesting features increase, the impact of avian predation
will increase (see separate discussion under ``Predation'' below). The
perception that these vertical structures are associated with predation
may cause lesser prairie-chickens to avoid areas near these structures
even when raptor densities are low. Sensitivity to electromagnetic
fields generated by the transmission lines may be another reason lesser
prairie-chickens might be avoiding these areas (Fernie and Reynolds
2005, p. 135) (see separate discussion under ``Wind Power and Energy
Transmission Operation and Development'' below).
Where grassland patches remained, overgrazing, drought, lack of
fire, woody plant and exotic grass invasions, and construction of
various forms of infrastructure impacted the integrity of the remaining
fragments (Brennan and Kuvlesky 2005, pp. 4-5). Domestic livestock
management following settlement tended to promote more uniform grazing
patterns, facilitated by construction of fences, which led to reduced
heterogeneity in remaining grassland fragments (Fuhlendorf and Engle
2001, p. 626; Pillsbury et al. 2011, p. 2). See related discussions in
the relevant sections below.
This ever-escalating fragmentation and homogenization of grasslands
contributed to reductions in the overall diversity and abundance of
grassland-endemic birds and caused populations of many species of
grassland-obligate birds, such as the lesser prairie-chicken to decline
(Coppedge et al. 2001, p. 48; Fuhlendorf and Engle, 2001, p. 626).
Fragmentation and homogenization of grasslands is particularly
detrimental for lesser prairie-chickens who typically prefer areas
where individual habitat needs are in close proximity to each other.
For example, in suitable habitats, desired vegetation for nesting and
brood rearing typically occurs within relatively short distances of the
breeding area.
Human-caused habitat fragmentation with its associated habitat loss
and degradation is considered by some to be the leading threat to
biodiversity (Hunter and Gibbs 2007, p. 182), and grasslands as a whole
are one of the most endangered ecosystems worldwide with agricultural
development continuing to be a primary factor (With et al. 2008, p.
3152). Human disturbances are rapidly increasing the prevalence of
edges in most terrestrial landscapes, and the process is not abating
(Samson 1980a, p. 250; Sisk and Battin 2002, p. 41). The continued loss
and conversion of grassland nesting and breeding habitat remains the
largest threat to the future of many species of grassland birds (NRCS
1999, p. 3). As a group, grassland nesting birds have experienced
greater declines in population size than any other group of birds, and
some of the most significant causes include habitat loss and
fragmentation, changes in land use, and habitat degradation (Knopf
1994, p. 251; Horn and Koford 2006, p. 109).
Effects of Habitat Fragmentation
While much of the conversion of native grasslands to agriculture in
the Great Plains was largely completed by the 1940s and has slowed in
more recent decades, grassland bird populations continue to decline
(With et al. 2008, p. 3153). Bird populations may initially appear
resistant to landscape change only to decline inexorably over time
because remaining grassland fragments may not be sufficient to prevent
longer term decline in their populations (With et al. 2008, p. 3165).
The decrease in patch size and increase in edges associated with
fragmentation are known to have caused reduced abundance, reduced nest
success, and reduced nest density in many species of grassland birds
(Pillsbury et al. 2011, p. 2).
Habitat fragmentation has been shown to negatively impact
population persistence and influence the species extinction process
through several mechanisms (Wilcove et al. 1986, p. 246). Once
fragmented, the remaining habitat fragments may be inadequate to
support crucial life-history requirements (Samson 1980b, p. 297). The
land-use matrix surrounding remaining suitable habitat fragments may
support high densities of predators or brood parasites (organisms that
rely on the nesting organism to raise their young), and the probability
of recolonization of unoccupied fragments decreases as distance from
the nearest suitable habitat patch increases (Wilcove et al. 1986, p.
248; Sisk and Battin 2002, p. 35). Invasion by undesirable plants and
animals is often facilitated around the perimeter or edge of the patch,
particularly where roads are present (Weller et al. 2002, p. 2).
Additionally, as animal populations become smaller and more isolated,
they are more susceptible to random (stochastic) events and reduced
genetic diversity via drift and inbreeding (Keller and Waller 2002, p.
230). Population viability depends on the size and spacing of remaining
fragments (Harrison and Bruna 1999, p. 226; With et al. 2008, p. 3153).
O'Connor et al. (1999, p. 56) concluded that grassland birds, as a
group, are particularly sensitive to habitat fragmentation, primarily
due to sensitivity to fragment size. Consequently, the effects of
fragmentation are the most severe on area-sensitive species (Herkert
1994, p. 468).
Area-sensitive species are those species that respond negatively to
decreasing habitat patch size (Robbins 1979, p. 198; Finch 1991, p. 1);
the term was initially applied to songbirds
[[Page 73855]]
inhabiting deciduous forests in eastern North America. However, an
increasing number of studies are showing that many grassland birds also
are area-sensitive and have different levels of tolerance to
fragmentation of their habitat (e.g., see Herkert 1994, entire; Winter
and Faaborg 1999, entire). For species that are area-sensitive, once a
particular fragment or patch of suitable habitat falls below the
optimum size, populations decline or disappear entirely even though
suitable habitat may continue to exist within the larger landscape.
When the overall amount of suitable habitat within the landscape
increases, the patch size an individual area-sensitive bird may utilize
generally tends to be smaller (Horn and Koford 2006, p. 115), but they
appear to maintain some minimum threshold (Fahrig 1997, p. 608; NRCS
1999, p. 4). Winter and Faaborg (1999, pp. 1429, 1436) reported that
the greater prairie-chicken was the most area-sensitive species
observed during their study, and this species was not documented from
any fragment of native prairie less than 130 ha (320 ac) in size.
Franklin et al. (2002, p. 23) described fragmentation in a
biological context. According to Franklin, habitat fragmentation occurs
when occupancy, reproduction, or survival of the organism has been
affected. The effects of fragmentation can be influenced by the extent,
pattern, scale, and mechanism of fragmentation (Franklin et al. 2002,
p. 27). Habitat fragmentation also can have positive, negative, or
neutral effects, depending on the species (Franklin et al. 2002, p.
27). As a group, grouse are considered to be particularly intolerant of
extensive habitat fragmentation due to their short dispersal distances,
specialized food habits, generalized antipredator strategies, and other
life-history characteristics (Braun et al. 1994, p. 432). Lesser
prairie-chickens in particular have a low adaptability to habitat
alteration, particularly activities that fragment suitable habitat into
smaller, less valuable pieces. Lesser prairie-chickens utilize habitat
patches with different vegetative structure dependent upon a particular
phase in their life cycle, and the loss of even one of these structural
components can significantly reduce the overall value of that habitat
to lesser prairie-chickens. Fragmentation not only reduces the size of
a given patch but also can reduce the interspersion or variation within
a larger habitat patch, possibly eliminating important structural
features crucial to lesser prairie-chickens.
Lesser prairie-chickens and other species of prairie grouse require
large expanses (i.e., 1,024 to 10,000 ha (2,530 to 24,710 ac)) of
interconnected, ecologically diverse native rangelands to complete
their life cycles (Woodward et al. 2001, p. 261; Flock 2002, p. 130;
Fuhlendorf et al. 2002, p. 618; Davis 2005, p. 3), more so than almost
any other grassland bird (Johnsgard 2002, p. 124). Davis (2005, p. 3)
states that the combined home range of all lesser prairie-chickens at a
single lek is about 49 sq km (19 sq mi or 12,100 ac). According to
Applegate and Riley (1998, p. 14), a viable lek will have at least six
males accompanied by an almost equal number of females. Because leks
need to be clustered so that interchange among different leks can occur
in order to reduce interbreeding problems on any individual lek, they
considered a healthy population to consist of a complex of six to ten
viable leks (Applegate and Riley 1998, p. 14). Consequently, most
grouse experts consider the lesser prairie-chicken to be an area-
sensitive species, and large areas of intact, unfragmented landscapes
of suitable mixed-grass, short-grass, and shrubland habitats are
considered essential to sustain functional, self-sustaining populations
(Giesen 1998, pp. 3-4; Bidwell et al. 2002, pp. 1-3; Hagen et al. 2004,
pp. 71, 76-77). Therefore, areas of otherwise suitable habitat can
readily become functionally unusable due to the effects of
fragmentation.
The lesser prairie-chicken has several life-history traits common
to most species of grouse that influence its vulnerability to the
impacts of fragmentation, including short lifespan, low nest success,
strong site fidelity, low mobility, and a relatively small home range.
This vulnerability is heightened by the considerable extent of habitat
loss that has already occurred over the range of the species. The
resiliency and redundancy of these populations have been reduced as the
number of populations that formerly occupied the known historical range
were lost or became more isolated by fragmentation of that range.
Isolation of remaining populations will continue to the extent these
populations remain or grow more separated by areas of unsuitable
habitat, particularly considering their limited dispersal capabilities
(Robb and Schroeder 2005, p. 36).
Fragmentation is becoming a particularly significant ecological
driver in lesser prairie-chicken habitats, and several factors are
known to be contributing to the observed destruction, modification, or
curtailment of the lesser prairie-chicken's habitat or range. Extensive
grassland and untilled rangeland habitats historically used by lesser
prairie-chickens have become increasingly scarce, and remaining areas
of these habitat types continue to be degraded or fragmented by
changing land uses. The loss and fragmentation of the mixed-grass,
short-grass, and shrubland habitats preferred by lesser prairie-
chickens has contributed to a significant reduction in the extent of
currently occupied range. Based on the cooperative mapping efforts led
by the Playa Lakes Joint Venture and Lesser Prairie-Chicken Interstate
Working Group, lesser prairie-chickens are estimated to now occupy only
about 16 percent of their estimated historically occupied range. What
habitat remains is now highly fragmented (Hagen et al. 2011, p. 64).
Several pervasive factors, such as conversion of native grasslands
to cultivated agriculture; change in the historical grazing and fire
regime; tree invasion and brush encroachment; oil, gas, and wind energy
development; road and highway expansion; and others, have been
implicated in not only permanently altering the Great Plains landscape
but in specifically causing much of the observed loss, alteration, and
fragmentation of lesser prairie-chicken habitat (Hagen and Giesen 2005,
np.; Elmore et al. 2009, pp. 2, 10-11; Hagen et al. 2011, p. 64).
Additionally, lesser prairie-chickens actively avoid areas of human
activity and noise or areas that contain certain vertical features
(Robel et al. 2004, pp. 260-262; Pitman et al. 2005, pp. 1267-1268;
Hagen et al. 2011, p. 70-71). Avoidance of vertical features such as
trees and transmission lines likely is due to frequent use of these
structures as hunting perches by birds of prey (Hagen et al. 2011, p.
72). Pitman et al. (2005, pp. 1267-1268) observed that lesser prairie-
chickens seldom nested or reared broods within approximately 177 m (580
ft) of oil or gas wellheads, 366 m (1,200 ft) of electrical
transmission lines, 792 m (2,600 ft) of improved roads, and 1,219 m
(4,000 ft) of buildings. The observed avoidance was likely influenced,
at least in part, by disturbances such as noise and visual obstruction
associated with these features. No lesser prairie-chicken nesting or
lekking was observed within 0.8 km (0.5 mi) of a gas line compressor
station, and otherwise suitable habitat was avoided within a 1.6-km (1-
mi) radius of a coal-fired power plant (Pitman et al. 2005, pp. 1267-
1268).
Oil and gas development activities, particularly drilling and road
and highway construction, also contribute to surface fragmentation of
lesser prairie-
[[Page 73856]]
chicken habitat for many of the same reasons observed with other
artificial structures (Hunt and Best 2004, p. 92). The incidence of oil
and gas exploration has been rapidly expanding within the range of the
lesser prairie-chicken. A more thorough discussion of oil and gas
activities within the range of the lesser prairie-chicken is discussed
below.
Many of the remaining habitat fragments and adjoining land use
types subsequently fail to meet important habitat requirements for
lesser prairie-chickens. Other human-induced developments, such as
buildings, fences, and many types of vertical structures, which may
have an overall smaller physical development footprint per unit area,
serve to functionally fragment otherwise seemingly suitable habitat;
this causes lesser prairie-chickens to cease or considerably reduce
their use of habitat patches impacted by these developments (Hagen et
al. 2011 pp. 70-71). As the intervening matrix between the remaining
fragments of suitable habitat becomes less suitable, dispersal patterns
can be disrupted, effectively isolating remaining islands of habitat.
These isolated fragments then become less resilient to the effects of
change in the overall landscape and likely will be more prone to
localized extinctions. The collective influence of habitat loss,
fragmentation, and disturbance effectively reduces the size and
suitability of the remaining habitat patches. Pitman et al. (2005, p.
1267) calculated that nesting avoidance at the distances they observed
would effectively eliminate some 53 percent (7,114 ha; 17,579 ac) of
otherwise suitable nesting habitat within their study area in
southwestern Kansas. Once the remaining habitat patches fall below the
minimum size required by lesser prairie-chickens, these patches become
uninhabitable even though they may otherwise provide optimum habitat
characteristics. Although a minimum size has not been established,
studies and expert opinion, including those regarding greater prairie-
chickens, suggest that the minimum parcel size is likely to exceed 100
ha (250 acres) (Samson 1980b, p. 295; Winter and Faaborg 1999, pp.
1429, 1436; Davis 2005, p. 3).
Fragmentation poses a threat to the persistence of local lesser
prairie-chicken populations through many of the same mechanisms
identified for other species of grassland birds. Factors such as
habitat dispersion and the extent of habitat change, including patch
size, edge density, and total rate of landscape change influence
juxtaposition and size of remaining patches of rangeland such that they
may no longer be large enough to support populations (Samson 1980b, p.
297; Woodward et al. 2001, pp. 269-272; Fuhlendorf et al. 2002, pp.
623-626). Additionally, necessary habitat heterogeneity may be lost,
and habitat patches may accommodate high densities of predators.
Ultimately lesser prairie-chicken interchange among suitable patches of
habitat may decrease, possibly affecting population and genetic
viability (Wilcove et al. 1986, pp. 251-252; Knopf 1996, p. 144).
Predation can have a major impact on lesser prairie-chicken demography,
particularly during the nesting and brood-rearing seasons (Hagen et al.
2007, p. 524). Patten et al. (2005b, p. 247) concluded that habitat
fragmentation, at least in Oklahoma, markedly decreases the probability
of long-term population persistence in lesser prairie-chickens.
Many of the biological factors affecting the persistence of lesser
prairie-chickens are exacerbated by the effects of habitat
fragmentation. For example, human population growth and the resultant
accumulation of infrastructure such as roads, buildings, communication
towers, and powerlines contribute to fragmentation. We expect that
construction of vertical infrastructure such as transmission lines will
continue to increase into the foreseeable future, particularly given
the increasing development of energy resources and urban areas (see
``Wind Power and Energy Transmission Operation and Development''
below). Where this infrastructure is placed in occupied lesser prairie-
chicken habitats, the lesser prairie-chicken likely will be negatively
affected. As the density and distribution of human development
continues in the future, direct and functional fragmentation of the
landscape will continue. The resultant fragmentation is detrimental to
lesser prairie-chickens because they rely on large, expansive areas of
contiguous native grassland to complete their life cycle. Given the
large areas of contiguous grassland needed by lesser prairie-chickens,
we expect that many of these types of developments anticipated in the
future will further fragment remaining blocks of suitable habitat and
reduce the likelihood of persistence of lesser prairie-chickens over
the long term. Long-term persistence is reduced when the suitability of
the remaining habitat patches decline, further contributing to the
scarcity of suitable contiguous blocks of habitat and resulting in
increased human disturbance as parcel size declines. Human populations
are increasing throughout the range of the lesser prairie-chicken, and
we expect this trend to continue. Given the demographic and economic
trends observed over the past several decades, residential development
will continue.
The cumulative influence of habitat loss and fragmentation on
lesser prairie-chicken distribution is readily apparent at the regional
scale. Lesser prairie-chicken populations in eastern New Mexico and the
western Texas Panhandle are isolated from the remaining populations in
Colorado, Kansas, and Oklahoma. On a smaller, landscape scale, core
populations of lesser prairie-chickens within the individual States are
isolated from other nearby populations by areas of unsuitable land uses
(Robb and Schroeder 2005, p. 16). Then, at the local level within a
particular core area of occupied habitat, patches of suitable habitat
have been isolated from other suitable habitats by varying degrees of
unsuitable land uses. Very few large, intact patches of suitable
habitat remain within the historically occupied landscape.
We conducted a spatial analysis of the extent of fragmentation
within the estimated occupied range of the lesser prairie-chicken.
Infrastructure features such as roads, transmission lines, airports,
cities and similar populated areas, oil and gas wells, and other
vertical features such as communication towers and wind turbines were
delineated. These features were buffered by known avoidance distances
and compared with likely lesser prairie-chicken habitat such as that
derived from the Southern Great Plains Crucial Habitat Tool and 2008
LandFire vegetation cover types. Based on this analysis, 99.8 percent
of the suitable habitat patches were less than 2,023 ha (5,000 ac) in
size. Our analysis revealed that only some 71 patches that were equal
to, or larger than, 10,117 ha (25,000 ac) exist within the entire five-
state estimated occupied range. Of the patches over 10,117 ha (25,000
ac), all were impacted by fragmenting features, just not to the extent
that the patch was fragmented into a smaller sized patch.
This analysis is a very conservative estimate of the extent of
fragmentation within the estimated occupied range. We only used
reasonably available datasets. Some datasets were unavailable, such as
the extent of fences, and other infrastructural features were not fully
captured because our datasets were incomplete for those features.
Unfortunately, a more precise quantification of the impact of habitat
loss and alteration on persistence of the
[[Page 73857]]
lesser prairie-chicken is complicated by a variety of factors including
time lags in response to habitat changes and a lack of detailed
historical information on habitat conditions.
In summary, habitat fragmentation is an ongoing threat that is
occurring throughout the occupied range of the lesser prairie-chicken.
Similarly, much of the historical range is disjunct and separated by
large expanses of unsuitable habitat. Once fragmented, most of the
factors contributing to habitat fragmentation cannot be reversed. Many
types of human developments likely will exist for extended time periods
and will have a significant, lasting adverse influence on persistence
of lesser prairie-chickens. Therefore, current and future habitat
fragmentation is a threat to the lesser prairie-chicken. In the
sections that follow, we will examine the various causes of lesser
prairie-chicken habitat fragmentation in more detail.
Habitat Conversion for Agriculture
At the time the lesser prairie-chicken was determined to be
taxonomically distinct from the greater prairie-chicken in 1885, much
of the historical range was already being subjected to alteration as
settlement of the Great Plains progressed. EuroAmerican settlement in
New Mexico and Texas began prior to the 1700s, and at least one trading
post already had been established in Colorado by 1825 (Coulson and
Joyce 2003, pp. 34, 41, 44). Kansas had become a territory by 1854 and
had already experienced an influx of settlers due to establishment of
the Santa Fe Trail in 1821 (Coulson and Joyce 2003, p. 37). Western
Oklahoma was the last area to experience extensive settlement with the
start of the land run in 1889.
Settlement obviously brought about many changes within the
historical range of the lesser prairie-chicken. Between 1915 and 1925,
considerable areas of prairie sod had been plowed in the Great Plains
and planted to wheat (Laycock 1987, p. 4). By the 1930s, the lesser
prairie-chicken had begun to disappear from areas where it had been
considered abundant with populations nearing extirpation in Colorado,
Kansas, and New Mexico, and markedly reduced in Oklahoma and Texas.
Several experts on the lesser prairie-chicken identified conversion of
native sand sagebrush and shinnery oak rangeland to cultivated
agriculture as an important factor in the decline of lesser prairie-
chicken populations (Copelin 1963, p. 8; Jackson and DeArment 1963, p.
733; Crawford and Bolen 1976a, p. 102; Crawford 1980, p. 2; Taylor and
Guthery 1980b, p. 2; Braun et al. 1994, pp. 429, 432-433; Mote et al.
1999, p. 3). By the 1930s, Bent (1932, pp. 283-284) hypothesized that
extensive cultivation and overgrazing had already caused the species to
disappear from portions of the historical range where lesser prairie-
chickens had once been abundant. Additional areas of previously
unbroken grassland were brought into cultivation in the 1940s, 1970s,
and 1980s (Laycock 1987, pp. 4-5). Bragg and Steuter (1996, p. 61)
estimated that by 1993, only 8 percent of the bluestem-grama
association and 58 percent of the mesquite-buffalo grass association,
as described by Kuchler (1964, entire), remained.
As the amount of native grasslands and untilled native rangeland
declined in response to increasing settlement, the amount of suitable
habitat capable of supporting lesser prairie-chicken populations
declined accordingly. Correspondingly, as the amount of available
suitable habitat diminished, carrying capacity was reduced and the
number of lesser prairie-chickens declined. However, documenting the
degree to which these settlement-induced impacts occurred is
complicated by a lack of solid historical information on population
size and extent of suitable habitat. Additionally, because cultivated
grain crops may have provided increased or more dependable winter food
supplies (Braun et al. 1994, p. 429), the initial conversion of smaller
patches of native prairie to cultivation may have been temporarily
beneficial to the species. Sharpe (1968, pp. 46-50) believed that the
presence of cultivated grains may have facilitated the temporary
occurrence of lesser prairie-chickens in Nebraska. However, landscapes
having greater than 20 to 37 percent cultivated grains may not support
stable lesser prairie-chicken populations (Crawford and Bolen 1976a, p.
102). While lesser prairie-chickens may forage in agricultural
croplands, they avoid landscapes dominated by cultivated agriculture,
particularly where small grains are not the dominant crop (Crawford and
Bolen 1976a, p. 102). Areas of cropland do not provide adequate year-
round food or cover for lesser prairie-chickens. Much of the historical
lesser prairie-chicken habitat has already been converted to
agricultural cropland.
In the Service's June 7, 1998, 12-month finding for the lesser
prairie-chicken (63 FR 31400), we attempted to assess the loss of
native rangeland using data available through the National Resources
Inventory of the USDA NRCS. However, very limited information on lesser
prairie-chicken status was available to us prior to 1982. When we
examined the 1992 National Resources Inventory Summary Report, we were
able to estimate the change in rangeland acreage between 1982 and 1992
by each State within the range of the lesser prairie-chicken. As
expected, when the trends were examined statewide, each of the five
States within the range of the lesser prairie-chicken showed a decline
in the amount of rangeland acreage over that time period, indicating
that conversion of lesser prairie-chicken habitat likely continued to
occur since the 1980s. In assessing the change specifically within
areas occupied by lesser prairie-chickens, we then narrowed our
analysis to just those counties where lesser prairie-chickens were
known to occur. That analysis, which was based on the information
available at that time, used a much smaller extent of estimated
occupied range than likely occurred at that time. The analysis of the
estimate change in rangeland acreage between 1982 and 1992, for
counties specifically within lesser prairie-chicken range, did not
demonstrate a statistically significant change, possibly due to small
sample size and large variation about the mean. In this analysis, the
data for the entire county was used without restricting to just those
areas estimated to be within the historical and currently occupied
ranges. A more recent, area-sensitive analysis was needed.
Although a more recent analysis of the Natural Resources Inventory
information was desired, we were unable to obtain specific county-by-
county information because the NRCS no longer releases county-level
information. Release of Natural Resources Inventory results is guided
by NRCS policy and is in accordance with Office of Management and
Budget and USDA Quality of Information Guidelines developed in 2001.
NRCS releases Natural Resources Inventory estimates only when they meet
statistical standards and are scientifically credible in accordance
with these policies. In general, the Natural Resources Inventory survey
system was not developed to provide acceptable estimates for areas as
small as counties but rather for analyses conducted at the national,
regional, and state levels, and for certain sub-state regions (Harper
2012).
We then attempted to use the 1992 National Land Cover Data (NLCD)
information to estimate the extent and change in certain land cover
types. The NLCD was the first land-cover mapping project that was
national in scope and is based on images from the Landsat thematic
mapper. No other national land-cover mapping program had
[[Page 73858]]
previously been undertaken, despite the availability of Landsat
thematic mapper information since 1984. The 1992 NLCD provides
information on 21 different land cover classes at a 30-meter
resolution. Based on the 1992 NLCD, and confining our analysis to just
the known historical and currently occupied range, we estimated that
there were 137,073.6 sq km (52,924.4 sq mi) of cultivated cropland in
the entire historical range and 16,436.9 sq km (6,346.3 sq mi) in the
currently occupied range. This includes areas planted to row crops,
such as corn and cotton, small grains like wheat and Hordeum vulgare
(barley), and fallow cultivated areas that had visible vegetation at
the time of the imagery.
Estimating the extent of untilled rangeland is slightly more
complicated. The extent of grassland areas dominated by native grasses
and forbs could be determined in a manner similar to that for
cultivated cropland. We estimated from the 1992 NLCD that there were
207,846 sq km (80,250 sq mi) of grassland within the entire historical
range, with only some 49,000 sq km (18,919 sq mi) of grassland in the
currently occupied range. However, the extent of shrubland also must be
included in the analysis because areas classified as shrubland (i.e.,
areas having a canopy cover of greater than 25 percent) are used by
lesser prairie-chicken, such as shinnery oak grasslands, and also may
be grazed by livestock. We estimated that there were 92,799 sq km
(35,830 sq mi) of shrubland within the entire historical range with
some 4,439 sq km (1,714 sq mi) of shrubland in the currently occupied
range, based on the 1992 NLCD.
These values can then be compared with those available through the
2006 NLCD information to provide a rough approximation of the change in
land use since 1992. In contrast to the 1992 NLCD, the 2006 NLCD
provides information on only 16 different land cover classes at a 30-
meter resolution. Based on this dataset, and confining our analysis to
just the known historical and currently occupied range, we estimated
that there were 126,579 sq km (48,872 sq mi) of cultivated cropland in
the entire historical range and 19,588 sq km (7,563 sq mi) in the
currently occupied range. This cover type consists of any areas used
annually to produce a crop and includes any land that is being actively
tilled. Estimating the extent of untilled rangeland is conducted
similarly to that for 1992. Using the 2006 NLCD, we estimated that
there were 163,011 sq km (62,939 sq mi) of grassland within the entire
historical range with some 42,728 sq km (16,497 sq mi) of grassland in
the currently occupied range. In 2006, the shrubland cover type was
replaced by a shrub-scrub cover type. This new cover type was defined
as the areas dominated by shrubs less than 5 m (16 ft) tall with a
canopy cover of greater than 20 percent. We estimated that there were
146,818 sq km (56,686 sq mi) of shrub/scrub within the entire
historical range, with some 10,291 sq km (3,973 sq mi) of shrub/scrub
in the currently occupied range.
Despite the difference in the classification of land cover between
1992 and 2006, we were able to make rough comparisons between the two
datasets. A comparison reveals that apparently the extent of cropland
within the entire historical range declined between 1992 and 2006. In
contrast, within the occupied range, the extent of cropland areas
increased during that same period. A comparison of the grassland and
untilled rangeland indicates that the amount of grassland declined in
both the historical range and the occupied range between 1992 and 2006.
However, the amount of shrub-dominated lands increased in both the
historical and currently occupied range. Overall, the estimated amount
of grassland and shrub-dominated land, as an indicator of untilled
rangelands, increased somewhat over the historical range during that
period but declined slightly within the occupied range during the same
period. Based on the definition of shrub/scrub cover type in 2006, the
observed increases in shrub-dominated cover only could have been due to
increased abundance of eastern red cedar, an invasive woody species
that tends to decrease suitability of grasslands and untilled
rangelands for lesser prairie-chickens (Woodward et al. 2001, pp. 270-
271; Fuhlendorf et al. 2002, p. 625).
However, direct comparison between the 1992 and 2006 NLCD is
problematic due to several factors. First, the 1992 NLCD was based on
an unsupervised classification algorithm (an iterative process used to
classify or ``cluster'' data obtained using remote sensing), whereas
NLCD 2001 and later versions were based on a supervised classification
and regression tree algorithm (data classification in which the data
analyst uses available information to assist in the classification).
Second, terrain corrections for the 1992 NLCD were based on digital
elevation models with a 90-meter spatial resolution, whereas terrain
correction for NLCD 2001 and later used 30-meter digital elevation
models. Third, the impervious surface mapping that is part of NLCD 2001
and later versions resulted in the identification of many more roads
than could be identified in the 1992 NLCD. However, most of these roads
were present in 1992. Fourth, the imagery for the 2001 NLCD and later
versions was corrected for atmospheric effects prior to classification,
whereas NLCD 1992 imagery was not. Lastly, there are subtle differences
between the NLCD 1992 and NLCD 2001 land-cover legends. Additionally,
we did not have an estimated occupied range for 1992. Instead we used
the occupied range as is currently estimated. The comparison in the
amount of cropland, grassland, and shrubland could be influenced by a
change in the amount of occupied range in 1992. Due to the influence of
CRP grasslands (discussed below) on the distribution of lesser prairie-
chickens in Kansas, the occupied range was much smaller in 1992. One
would anticipate that the influence of CRP establishment north of the
Arkansas River in Kansas might have led to considerably more areas of
grassland in 2006 as compared to 1992. However, the amount of grassland
was observed to have declined within the occupied range of the lesser
prairie-chicken between 1992 and 2006, possibly indicating that the
extent of grasslands continued to decline despite the increase in CRP
grasslands.
If we restrict our analysis to Kansas alone, the extent of
grasslands in 1992 was about 39,381 sq km (15,205 sq mi) within the
historical range and 22,923 sq km (8850 sq mi) in the occupied range.
In 2006, the extent of grasslands in Kansas was some 27,351 sq km
(10,560 sq mi) within the historical range and 18,222 sq km (7,035 sq
mi) in the occupied range. While not definitive, the analysis indicates
that the extent of grasslands continued to decline even in Kansas where
lesser prairie-chicken populations are declining but more robust than
in other States.
In summary, conversion of the native grassland habitats used by
lesser prairie-chickens for agricultural uses has resulted in the
permanent, and in some limited instances, temporary loss or alteration
of habitats used for feeding, sheltering, and reproduction.
Consequently, populations of lesser prairie-chickens likely have been
extirpated or significantly reduced, underscoring the degree of impact
that historical conversion of native grasslands has posed to the
species. We expect a very large proportion of the land area that is
currently in agricultural production will likely remain so over the
foreseeable future because we have no information to suggest that
agricultural practices are likely to
[[Page 73859]]
change. While persistent drought and declining supplies of water for
irrigation may lead to conversion of some croplands to a noncropland
state, we anticipate that the majority of cropland will continue to be
used to produce a crop. Because considerable areas of suitable arable
lands have already been converted to agricultural production, we do not
expect significant additional, future habitat conversion to agriculture
within the range of the lesser prairie-chicken. However, as
implementation of certain agricultural conservation programs like the
CRP change programmatically, some continued conversion of grassland
back into cultivation is still expected to occur. Conservation Reserve
Program contracts, as authorized and outlined by regulation, are of
limited, temporary duration, and the program is subject to funding by
Congress. We also recognize that the historical large-scale conversion
of grasslands to agricultural production has resulted in fragmented
grassland and shrubland habitats used by lesser prairie-chickens such
that currently occupied lands are not adequate to provide for the
conservation of the species into the foreseeable future, particularly
when cumulatively considering the threats to the lesser prairie-
chicken.
Conservation Reserve Program (CRP)
The loss of lesser prairie-chicken habitat due to conversion of
native grasslands to cultivated agriculture has been mitigated somewhat
by the CRP. Authorization and subsequent implementation of the CRP
began under the 1985 Food Security Act and, since that time, has
facilitated restoration of millions of acres of marginal and highly
erosive cropland to grassland, shrubland, and forest habitats (Riffell
and Burger 2006, p. 6). The CRP is administered by the USDA's Farm
Service Agency and was established primarily to control soil erosion on
cropland by converting cropped areas to a vegetative cover such as
perennial grassland. Under the general signup process, lands are
enrolled in CRP using a competitive selection process. However, certain
environmentally desirable lands can be enrolled at any time under a
continuous signup process. Additional programs, such as the
Conservation Reserve Enhancement Program and designation as a
Conservation Priority Area can be used to target enrollment of CRP.
Participating producers receive an annual rental payment for the
duration of a multiyear CRP contract. Cost sharing is provided to
assist in the establishment of the vegetative cover practices. Once the
CRP contract expires, typically after 10 to 15 years, landowners have
the option to reenroll in the program, convert lands back to cropland,
or leave lands in a noncropland state.
In 2009, the enrollment authority or acreage cap for CRP was
reduced from 15.9 million ha (39.2 million ac) nationwide to 12.9
million ha (32.0 million ac) through fiscal year 2012, with 1.8 million
ha (4.5 million ac) allocated to targeted (continuous) signup programs.
Future enrollment authority is unknown and dependent on passage of a
new Farm Bill and subsequent funding by Congress. Within a given
county, no more than 25 percent of that county's cropland acreage may
be enrolled in CRP and the Wetland Reserve Program. A waiver of this
acreage cap may be granted under certain circumstances. These caps
influence the maximum amounts of cropland that may exist in CRP at any
one time. Since 2004, midcontract management has been required on
contracts executed after fiscal year 2004 and is voluntary for
contracts accepted before that time. Typically these management
activities, such as prescribed burning, tree thinning, disking, or
herbicide application to control invasive species, are generally
prohibited during the primary avian nesting and brood rearing season.
Under the CRP, several forms of limited harvest, haying, and grazing
are authorized, including emergency haying and grazing. Emergency
haying and grazing may be granted on CRP lands to provide relief to
ranchers in areas affected by drought or other natural disaster to
minimize loss or culling of livestock herds. Haying and grazing under
both managed and emergency conditions have the potential to
significantly negatively impact vegetation if the amount of forage
removed is excessive and prolonged, or if livestock numbers are
sufficient to contribute to soil compaction. Additionally, the
installation of wind turbines, windmills, wind monitoring devices, or
other wind-powered generation equipment may be installed on CRP acreage
on a case-by-case basis. Up to 2 ha (5 ac) of wind turbines per
contract may be approved.
Lands enrolled in CRP encompasses a significant portion of
currently occupied range in several lesser prairie-chicken States, but
particularly in Kansas where an increase in the lesser prairie-chicken
population is directly related to the amount of land that was enrolled
in the CRP and planted to native grasses. Enrollment information is
publically available from the Farm Services Agency at the county level.
However, specific locations of individual CRP acreages are not
publically available due to needs to protect privacy of the individual
landowner. The Playa Lakes Joint Venture has an agreement with the Farm
Services Agency that allows them to use available data on individual
CRP allotments for conservation purposes, provided the privacy of the
landowner is protected. The Playa Lakes Joint Venture, using this
information, has been able to determine the extent of CRP lands within
the estimated occupied range of the lesser prairie-chicken over all
five lesser prairie-chicken States (McLachlan et al. 2011, p. 24). In
conducting this analysis, they restricted their analysis to only those
lands that were planted to a grass type of conservation cover and they
evaluated all lands within the estimated occupied range, including a 16
km (10 mi) buffer surrounding the occupied areas. Based on this
analysis, Kansas was determined to have the most land enrolled in CRP
with a grass cover type. Kansas has some 600,000 ha (1,483,027 ac)
followed by Texas with some 496,000 ha (1,227,695 ac) of grassland CRP.
Enrolled acreages in Colorado, New Mexico, and Oklahoma are 193,064 ha
(477,071 ac), 153,000 ha (379,356 ac), and 166,000 ha (410,279 ac),
respectively. The amount of grass type CRP within the estimated
occupied range totals just over 1.6 million ha (3.9 million ac). While
the extent of CRP may have changed slightly due to recent enrollments
and re-enrollments and any contract expirations that may have occurred
since the study was conducted, the figures serve to highlight the
importance of CRP for lesser prairie-chickens. Based on the estimated
amount of occupied habitat remaining in these States, CRP fields having
a grass type of conservation cover in Kansas comprise some 20.6 percent
of the occupied lesser prairie-chicken range, 45.8 percent of the
occupied range in Colorado, and 40.9 percent of the occupied range in
Texas. New Mexico and Oklahoma have smaller percentages of CRP within
the occupied range, 17.9 and 15.1 percent, respectively. When the sizes
of the CRP fields were examined, Kansas had some 53 percent, on
average, of the enrolled lands that constituted large habitat blocks,
as defined. A large block was defined as areas that were at least 5,000
acres in size with minimal amounts of woodland, roads, and developed
areas (McLachlan et al. 2011, p. 14). All of the other States had 15
percent or less of the enrolled CRP in a large block configuration.
[[Page 73860]]
The importance of CRP habitat to the status and survival of lesser
prairie-chicken was recently emphasized by Rodgers and Hoffman (2005,
pp. 122-123). They determined that the presence of CRP lands planted
with native species of grasses facilitated the expansion of lesser
prairie-chicken range in Colorado, Kansas, and New Mexico. The range
expansion in Kansas resulted in strong population increases there
(Rodgers and Hoffman 2005, pp. 122-123). However, in Oklahoma, Texas,
and some portions of New Mexico, many CRP fields were planted with a
monoculture of introduced grasses. Where introduced grasses were
planted, lesser prairie-chickens did not demonstrate a range expansion
or an increase in population size (Rodgers and Hoffman 2005, p. 123).
An analysis of lesser prairie-chicken habitat quality within a
subsample of 1,019 CRP contracts across all five lesser prairie-chicken
States was recently conducted by the Rocky Mountain Bird Observatory
(Ripper and VerCauteren 2007, entire). They found that, particularly in
Oklahoma and Texas, contracts executed during earlier signup periods
allowed planting of monocultures of exotic grasses, such as
Bothriochloa sp. (old-world bluestem) and Eragrostis curvula (weeping
lovegrass), which provide poor-quality habitat for lesser prairie-
chicken (Ripper and VerCauteren 2007, p. 11). Correspondingly, a high-
priority conservation recommendation from this study intended to
benefit lesser prairie-chickens was to convert existing CRP fields
planted in exotic grasses into fields supporting taller, native grass
species and to enhance the diversity of native forbs and shrubs used
under these contracts. Generally, pure stands of grass lack the habitat
heterogeneity and structure preferred by lesser prairie-chickens.
Subsequent program adjustments have encouraged the planting of native
grass species on CRP enrollments.
Predicting the fate of the CRP and its influence on the lesser
prairie-chicken into the future is difficult. The expiration of a
contract does not automatically trigger a change in land use. The
future of CRP lands is dependent upon three sets of interacting
factors: The long-term economies of livestock and crop production, the
characteristics and attitudes of CRP owners and operators, and the
direct and indirect incentives of existing and future agricultural
policy (Heimlich and Kula 1990, p. 7). As human populations continue to
grow, the worldwide demands for livestock and crop production are
likely to continue to grow. If demand for U.S. wheat and feed grains is
high, pressure to convert CRP lands back to cropland will be strong.
However, in 1990, all five States encompassing the historical range of
the lesser prairie-chicken were among the top 10 States expected to
retain lands in grass following contract expiration (Heimlich and Kula
1990, p. 10). A survey of the attitudes of existing CRP contract
holders in Kansas, where much of the existing CRP land occurs, revealed
that slightly over 36 percent of landowners with an existing contract
had made no plans or were uncertain about what they would do once the
CRP contract expired (Diebel et al. 1993, p. 35). An equal percentage
stated that they intended to keep lands in grass for livestock grazing
(Diebel et al. 1993, p. 35). Some 24 percent of enrolled landowners
expected they would return to annual crop production in accordance with
existing conservation compliance provisions (Diebel et al. 1993, p.
35). The participating landowners stated that market prices for crops
and livestock was the most important factor influencing their decision,
with availability of cost sharing for fencing and water development for
livestock also being an important consideration. However, only a small
percentage, about 15 percent, were willing to leave their CRP acreages
in permanent cover after contract expiration where incentives were
lacking (Diebel et al. 1993, p. 8).
Although demand for agricultural commodities and the opinions of
the landowners are important, existing and future agricultural policy
is expected to have the largest influence on the fate of CRP (Heimlich
and Kula 1990, p. 10). The CRP was most recently renewed under the
Food, Conservation, and Energy Act of 2008 and is due for
reauthorization in 2012. The most recent CRP general signup for
individual landowners began March 12, 2012, and expired April 13, 2012.
The extent to which existing CRP lands were reenrolled or new lands
enrolled into the program is unknown. A new Farm Bill, which will
establish the guidelines for CRP over the next five years, is currently
under development and the ramifications of this policy on the future of
CRP are unknown.
The possibility exists that escalating grain prices due to the
recent emphasis on generating domestic energy from biofuels, such as
ethanol from corn, grain sorghum, and switchgrass, combined with
Federal budget reductions that reduce or eliminate CRP enrollments and
renewals, will result in an unprecedented conversion of existing CRP
acreage within the Great Plains back to cropland (Babcock and Hart
2008, p. 6). In 2006, the USDA Farm Service Agency provided a small
percentage of current CRP contract holders whose contracts were set to
expire during 2007 to 2010, with an opportunity (termed REX) to
reenroll (10-15 year terms) or extend (2-5 year terms) their contracts.
The opportunity to reenroll or extend their contracts was based on the
relative environmental benefits of each contract. In March of 2007, the
USDA expected that some 9.7 million ha (23.9 million ac) out of the
total 11.3 million ha (28 million ac) of eligible CRP contracts would
be reenrolled. The remaining 1.7 million ha (4.1 million ac) would be
eligible for conversion to crop production or other uses.
Should large-scale loss or reductions in CRP acreages occur, either
by reduced enrollments or by conversion back to cultivation upon
expiration of existing contracts, the loss of CRP acreage would further
diminish the amount of suitable lesser prairie-chicken habitat. This
concern is particularly relevant in Kansas where CRP acreages planted
to native grass mixtures facilitated an expansion of the occupied
lesser prairie-chicken range in that State. In States that planted a
predominance of CRP to exotic grasses, loss of CRP in those States
would not be as significant as it would in Kansas where CRP largely was
planted to native grass and exists in relatively larger habitat blocks.
A reduction in CRP acreage could lead to contraction of the currently
occupied range and reduced numbers of lesser prairie-chicken rangewide
and poses a threat to the status of existing lesser prairie-chicken
populations. While the CRP program has had a beneficial effect on the
lesser prairie-chicken, particularly in Kansas, the contracts are short
term in nature and, given current government efforts to reduce the
Federal budget deficit, additional significant new enrollments in CRP
are not anticipated. However, we anticipate that some CRP grassland
acreages would be reenrolled in the program once contracts expire,
subject to the established acreage cap.
A recent analysis of CRP by the National Resources Conservation
Service (J. Ungerer and C. Hagen, 2012, Personal Communication)
revealed that between 2008 and 2011, some 675,000 acres of CRP
contracts expired within the estimated occupied range, the majority
located in Kansas. However many of those expired lands remained in
grass. Values varied from a low of 72.4 percent remaining in grass in
Colorado to a high of 97.5 percent in
[[Page 73861]]
New Mexico. Kansas was estimated to have some 90.2 percent of the
expired acres during this period still in grass. Values for Oklahoma
and Texas had not yet been determined. We expect that many of the
acreages that remain in grass in New Mexico are likely composed of
exotic species of grasses. Despite a small overall loss in CRP acreage,
we are encouraged by the relatively high percentage of CRP that remains
in grass. However, we remain concerned that the potential for
significant loss of CRP acreages remains, particularly considering the
attitudes of Kansas landowners as previously discussed above. The
importance of CRP to lesser prairie-chickens, particularly in Kansas,
is high and continued loss of CRP within the occupied range would be
detrimental to lesser prairie-chicken conservation.
We also remain concerned about the future value of these grasslands
to the lesser prairie-chicken. We assume that many of these CRP
grasslands that remain in grass after their contract expires could be
influenced by factors addressed elsewhere in this proposed rule.
Encroachment by woody vegetation, fencing, wind power development, and
construction of associated transmission lines have the potential to
reduce the value of these areas even if they continue to remain in
grass. Unless specific efforts are made to target enrollment of CRP in
areas important to lesser prairie-chickens, future enrollments likely
will do little to reduce fragmentation or enhance connectivity between
existing populations. Considering much of the existing CRP in Kansas
was identified as supporting large blocks of suitable habitat, as
discussed above, fracturing of these blocks into smaller, less suitable
parcels by the threats identified in this proposed rule would reduce
the value of these grasslands for lesser prairie-chickens.
In summary, we recognize that lands already converted to cultivated
agriculture are located throughout the current and historical range of
the lesser prairie-chicken and are, therefore, perpetuating habitat
fragmentation within the range of the lesser prairie-chicken. We expect
that CRP will continue to provide a means of temporarily restoring
cropland to grassland and provide habitat for lesser prairie-chickens
where planting mixtures and maintenance activities are appropriate.
However, we expect that, in spite of the at least temporary benefits
provided by CRP, most of the areas already in agricultural production
will remain so into the foreseeable future. While CRP has contributed
to restoration of grassland habitats and has influenced abundance and
distribution of lesser prairie-chickens in some areas, we expect these
lands to be subject to conversion back to cropland as economic
conditions change in the foreseeable future possibly reducing the
overall benefit of the CRP to the landowner. We do not anticipate that
CRP, at current and anticipated funding levels, will cause significant,
permanent increases in the extent of native grassland within the range
of the lesser prairie-chicken (Coppedge et al. 2001, p. 57).
Consequently, CRP grasslands alone are not adequate to provide for the
long-term persistence of the species, particularly when the known
threats to the lesser prairie-chicken are considered cumulatively.
Livestock Grazing
Habitats used by the lesser prairie-chicken are dominated naturally
by a diversity of drought-tolerant perennial grasses and shrubs.
Grazing has long been an ecological driving force within the ecosystems
of the Great Plains (Stebbins 1981, p. 84), and much of the untilled
grasslands within the range of the lesser prairie-chicken continue to
be grazed by livestock and other animals. The evolutionary history of
the mixed-grass prairie has produced endemic bird species adapted to an
ever-changing mosaic of lightly to severely grazed grasslands (Bragg
and Steuter 1996, p. 54; Knopf and Samson 1997, pp. 277-279, 283). As
such, grazing by domestic livestock is not inherently detrimental to
lesser prairie-chicken management. However, recent grazing practices
have produced habitat conditions that differ in significant ways from
the historical mosaic, such as by reducing the amount of ungrazed to
lightly grazed habitat. These altered conditions are less suitable for
the lesser prairie-chicken (Hamerstrom and Hamerstrom 1961, pp. 289-
290; Davis et al. 1979, pp. 56, 116; Taylor and Guthery 1980a, p. 2;
Bidwell and Peoples 1991, pp. 1-2).
Livestock grazing most clearly affects lesser prairie-chickens when
it alters the composition and structure of mixed-grass habitats used by
the species. Domestic livestock and native ungulates differentially
alter native prairie vegetation, in part through different foraging
preferences (Steuter and Hidinger 1999, pp. 332-333; Towne et al. 2005,
p. 1557). Additionally, domestic livestock grazing, particularly when
confined to small pastures, often is managed in ways that produces more
uniform utilization of forage and greater total utilization of forage,
in comparison to conditions produced historically by free-ranging
plains bison (Bison bison) herds. For example, grazing by domestic
livestock tends to be less patchy, particularly when livestock are
confined to specific pastures. Such management practices and their
consequences may actually exceed the effect produced by differences in
forage preferences (Towne et al. 2005, p. 1558) but, in any case,
produce an additive effect on plant community characteristics.
The effects of livestock grazing, particularly overgrazing or
overutilization, are most readily observed through changes in plant
community composition and other vegetative characteristics (Fleischner
1994, pp. 630-631; Stoddart et al. 1975, p. 267). Typical vegetative
indicators include changes in the composition and proportion of desired
plant species and overall reductions in forage. Plant height and
density may decline, particularly when plant regeneration is hindered,
and community composition shifts to show increased proportions of less
desirable species.
Grazing management favorable to persistence of the lesser prairie-
chicken must ensure that a diversity of plants and cover types,
including shrubs, remain on the landscape (Taylor and Guthery 1980a, p.
7; Bell 2005, p. 4), and that utilization levels leave sufficient cover
in the spring to ensure that lesser prairie-chicken nests are
adequately concealed from predators (Davis et al. 1979, p. 49; Wisdom
1980, p. 33; Riley et al. 1992, p. 386; Giesen 1994a, p. 98). Where
grazing regimes leave limited residual cover in the spring, protection
of lesser prairie-chicken nests may be inadequate and desirable food
plants can be scarce (Bent 1932, p. 280; Cannon and Knopf 1980, pp. 73-
74; Crawford 1980, p. 3). Because lesser prairie-chickens depend on
medium and tall grass species that are preferentially grazed by cattle,
in regions of low rainfall, the habitat is easily overgrazed in regard
to characteristics needed by lesser prairie-chickens (Hamerstrom and
Hamerstrom 1961, p. 290). In addition, when grasslands are in a
deteriorated condition due to overgrazing and overutilization, the
soils have less water-holding capacity, and the availability of
succulent vegetation and insects utilized by lesser prairie-chicken
chicks is reduced. Many effects of overgrazing and overutilization on
habitat quality are similar to effects produced by drought and likely
are exacerbated by actual drought conditions (Davis et al. 1979, p.
122; Merchant 1982, pp. 31-33) (see separate discussion under
``Drought'' in ``Extreme Weather Events'' below).
[[Page 73862]]
Fencing is a fundamental tool of livestock management but often
leads to structural fragmentation of the landscape. Fencing and related
structural fragmentation can be particularly detrimental to the lesser
prairie-chicken in areas, such as western Oklahoma, where initial
settlement patterns favored larger numbers of smaller parcels for
individual settlers (Patten et al. 2005b, p. 245). Fencing also can
cause direct mortality through forceful collisions, by creation of
raptor perch sites, and by creation of enhanced movement corridors for
predators (Wolfe et al. 2007, pp. 96-97, 101). However, not all fences
present the same mortality risk to lesser prairie-chickens. Mortality
risk would appear to be dependent on factors such as fencing design
(height, type, number of strands), landscape topography, and proximity
to habitats, particularly leks, used by lesser prairie chickens. Other
factors such as the length and density of fences also appear to
influence the effects of these structures on lesser prairie-chickens.
However, studies on the impacts of different fencing designs and
locations with respect to collision mortality in lesser prairie-
chickens have not been conducted. Additional discussion related to
impacts of collisions with fences and similar linear features are found
in the ``Collision Mortality'' section below.
Recent rangeland management includes influential elements besides
livestock species selection, grazing levels, and fencing, such as
applications of fire (usually to promote forage quality for livestock)
and water management regimes (usually to provide water supplies for
livestock). Current grazing management strategies are commonly
implemented in ways that are vastly different and less variable than
historical conditions (Knopf and Sampson 1997, pp. 277-79). These
practices have contributed to overall changes in the composition and
structure of mixed-grass habitats, often making them less suitable for
the lesser prairie-chicken.
Livestock are known to inadvertently flush lesser prairie-chickens
and trample lesser prairie-chicken nests. This can cause direct
mortality to lesser prairie-chicken eggs or chicks or may cause adults
to permanently abandon their nests, again resulting in loss of young.
For example, Pitman et al. (2006a, pp. 27-29) estimated nest loss from
trampling by cattle to be about 1.9 percent of known nests.
Additionally, even brief flushings of adults from nests can expose eggs
and chicks to predation. Although documented, the significance of
direct livestock effects on the lesser prairie-chicken is largely
unknown.
Detailed, rangewide information is lacking on the extent,
intensity, and forms of recent grazing, and associated effects on the
lesser prairie-chicken. However, livestock grazing occurs over such a
large portion of the area currently occupied by lesser prairie-chickens
that any degradation of habitat it causes is likely to produce
population-level impacts on the lesser prairie-chicken. Where uniform
grazing regimes have left inadequate residual cover in the spring,
detrimental effects to lesser prairie-chicken populations have been
observed (Bent 1932, p. 280; Davis et al. 1979, pp. 56, 116; Cannon and
Knopf 1980, pp. 73-74; Crawford 1980, p. 3; Bidwell and Peoples 1991,
pp. 1-2; Riley et al. 1992, p. 387; Giesen 1994a, p. 97). Some studies
have shown that overgrazing in specific portions of the lesser prairie-
chicken's occupied range has been detrimental to the species. Taylor
and Guthery (1980a, p. 2) believed overgrazing explained the demise of
the lesser prairie-chicken in portions of Texas but thought lesser
prairie-chickens could maintain low populations in some areas with
high-intensity, long-term grazing. In New Mexico, Patten et al. (2006,
pp. 11, 16) found that grazing did not have an overall influence on
where lesser prairie-chickens occurred within their study areas, but
there was some evidence that the species did not nest in portions of
the study area subjected to cattle grazing. In some areas within lesser
prairie-chicken range, long-term high-intensity grazing results in
reduced availability of lightly grazed habitat available to support
successful nesting (Jackson and DeArment 1963, p. 737; Davis et al.
1979, pp. 56, 116; Taylor and Guthery 1980a, p. 12; Davies 1992, pp. 8,
13).
In summary, domestic livestock grazing (including management
practices commonly used to benefit livestock production) has altered
the composition and structure of mixed-grass habitats historically used
by the lesser prairie-chicken. Much of the remaining remnants of mixed-
grass prairie and rangeland, while still important to the lesser
prairie-chicken, exhibit conditions quite different from those that
prevailed prior to EuroAmerican settlement. These changes have
considerably reduced the suitability of remnant areas as habitat for
lesser prairie-chickens. Where habitats are no longer suitable for
lesser prairie-chicken, these areas can contribute to fragmentation
within the landscape even though they may remain in native prairie.
Where improper livestock grazing has degraded native grasslands and
shrublands, we do not expect those areas to significantly contribute to
persistence of the lesser prairie-chicken, particularly when considered
cumulatively with the influence of the other known threats.
Collision Mortality
Wire fencing is ubiquitous throughout the Great Plains as the
primary means of confining livestock to ranches and pastures or
excluding them from areas not intended for grazing, such as CRP lands,
agricultural fields, and public roads. As a result, thousands of miles
of fencing, primarily barbed wire, have been constructed throughout
lesser prairie-chicken range. Like most grassland wildlife throughout
the Great Plains, the lesser prairie-chicken evolved in open habitats
free of vertical structures or flight hazards, such as linear wires.
Until recently, unnatural linear features such as fences, power lines,
and similar wire structures were seldom perceived as a significant
threat at the population level (Wolfe et al. 2007, p. 101). Information
on the influence of vertical structures is provided elsewhere in this
document.
Mortality of prairie grouse caused by collisions with power lines
has been occurring for decades, but the overall extent is largely
unmonitored. Leopold (1933, p. 353) mentions a two-cable transmission
line in Iowa where the landowner would find as many as a dozen dead or
injured greater prairie-chickens beneath the line annually. Prompted by
recent reports of high collision rates in species of European grouse
(Petty 1995, p. 3; Baines and Summers 1997, p. 941; Bevanger and
Broseth 2000, p. 124; Bevanger and Broseth 2004, p. 72) and seemingly
unnatural rates of mortality in some local populations of lesser
prairie-chicken, the Sutton Center began to investigate collision
mortality in lesser prairie-chickens. From 1999 to 2004, researchers
recovered 322 carcasses of radio-marked lesser prairie-chickens in New
Mexico, Oklahoma, and portions of the Texas panhandle. For lesser
prairie-chickens in which the cause of death could be determined, 42
percent of mortality in Oklahoma was attributable to collisions with
fences, power lines, or automobiles. In New Mexico, only 14 percent of
mortality could be traced to collision. The difference in rates of
observed collision between States was attributed to differences in the
amount of fencing on the landscape resulting from differential land
settlement patterns in the two States (Patten et al. 2005b, p. 245).
[[Page 73863]]
With between 14 and 42 percent of adult lesser prairie-chicken
mortality currently attributable to collision with human-induced
structures, Wolfe et al. (2007, p. 101) assert that fence collisions
will negatively influence long-term population viability for lesser
prairie-chickens. Precisely quantifying the scope of the impact of
fence collisions rangewide is difficult due to a lack of relevant
information. However, we suspect that hundreds of miles of fences are
constructed annually within the historical range of the lesser prairie-
chicken. Frequently these fences replace existing fence lines and often
new fences are constructed. We suspect that only rarely are old fences
removed due to labor involved in removing unneeded fences. While we are
unable to quantify the amount of new fencing being constructed,
collision with fences and other linear features is likely an important
source of mortality for lesser prairie-chicken, particularly in some
localized areas.
Fence collisions are known to be a significant source of mortality
in other grouse. Moss (2001, p. 256) modeled the estimated future
population of capercaille grouse (Tetrao urogallus) in Scotland and
found that, by removing fence collision risks, the entire Scotland
breeding population would consist of 1,300 instead of 40 females by
2014. Similarly, recent experiments involving fence marking to increase
visibility resulted in a 71 percent overall reduction in grouse
collisions in Scotland (Baines and Andrew 2003, p. 174). Additionally,
proximity to power lines has been associated with extirpations of
Gunnison and greater sage-grouse (Wisdom et al. 2011, pp. 467-468).
As previously discussed, collision and mortality risk appears to be
dependent on factors such as fencing design (height, type, number of
strands), length, and density, as well as landscape topography and
proximity of fences to habitats used by lesser prairie-chickens.
Although single-strand, electric fences may be a suitable substitute
for barbed-wire fences, we have no information demonstrating such is
the case. However, marking the top two strands of barbed-wire fences
increases their visibility and may help minimize incidence of collision
(Wolfe et al. 2009, entire).
In summary, power lines and unmarked wire fences are known to cause
injury and mortality of lesser prairie-chickens, although the specific
rangewide impact on lesser prairie-chickens is largely unquantified.
However, the prevalence of fences and power lines within the species'
range suggests these structures may have at least localized, if not
widespread, detrimental effects. While some conservation programs have
emphasized removal of unneeded fences, we believe that, without
substantially increased removal efforts, a majority of existing fences
will remain on the landscape indefinitely. Existing fences likely
operate cumulatively with other mechanisms described in this proposed
rule to diminish the ability of the lesser prairie-chicken to persist,
particularly in areas with a high density of fences.
Shrub Control and Eradication
Shrub control and eradication are additional forms of habitat
alteration that can influence the availability and suitability of
habitat for lesser prairie-chickens (Jackson and DeArment 1963, pp.
736-737). Herbicide applications (primarily 2,4-D and tebuthiuron) to
reduce or eliminate shrubs from native rangelands is a common ranching
practice throughout much of lesser prairie-chicken range, primarily
intended to increase forage production for livestock. Through foliar
(2,4-D) or pelleted (tebuthiuron) applications, these herbicides are
designed to suppress or kill, by repeated defoliation, dicotyledonous
plants such as forbs, shrubs, and trees, while causing no significant
damage to monocotyledon plants such as grasses.
As defined here, control includes efforts that are designed to have
a relatively short-term, temporary effect, generally less than 4 to 5
years, on the target shrub. Eradication consists of efforts intended to
have a more long-term or lasting effect on the target shrub. Control
and eradication efforts have been applied to both shinnery oak and sand
sagebrush dominated habitats, although most shrub control and
eradication efforts are primarily focused on shinnery oak. Control or
eradication of sand sagebrush occurs within the lesser prairie-chicken
range (Rodgers and Sexson 1990, p. 494), but the extent is unknown.
Control or eradication of sand sagebrush appears to be more prevalent
in other parts of the western United States. Other species of shrubs,
such as skunkbush sumac or Prunus angustifolia (Chicksaw plum), also
have been the target of treatment efforts.
Shinnery oak is toxic to cattle when it first produces leaves in
the spring, and it also competes with more palatable grasses and forbs
for water and nutrients (Peterson and Boyd 1998, p. 8). In areas where
Gossypium spp. (cotton) is grown, shinnery oak often is managed for the
control of boll weevil (Anthonomus grandis), which can destroy cotton
crops (Slosser et al. 1985, entire). Boll weevils overwinter in areas
where large amounts of leaf litter accumulate but tend not to
overwinter in areas where grasses predominate (Slosser et al. 1985, p.
384). Fire is typically used to remove the leaf litter, and then
tebuthiuron, an herbicide, is used to remove shinnery oak (Plains
Cotton Growers 1998, pp. 2-3). Prior to the late 1990s, approximately
40,469 ha (100,000 ac) of shinnery oak in New Mexico and 404,685 ha
(1,000,000 ac) of shinnery oak in Texas were lost due to the
application of tebuthiuron and other herbicides for agriculture and
range improvement (Peterson and Boyd 1998, p. 2).
The shinnery oak vegetation type is endemic to the southern Great
Plains and is estimated to have historically covered an area of 2.3
million ha (over 5.6 million ac), although its current range has been
considerably reduced through eradication (Mayes et al. 1998, p. 1609).
The distribution of shinnery oak overlaps much of the historical lesser
prairie-chicken range in New Mexico, southwestern Oklahoma, and Texas
panhandle region (Peterson and Boyd 1998, p. 2). Sand sagebrush tends
to be the dominant shrub in lesser prairie-chicken range in Kansas and
Colorado as well as portions of northwestern Oklahoma, the northeast
Texas panhandle, and northeastern New Mexico.
Once shinnery oak is eradicated, it is unlikely to recolonize
treated areas. Shinnery oak is a rhizomatous shrub that reproduces very
slowly and does not invade previously unoccupied areas (Dhillion et al.
1994, p. 52). Shinnery oak rhizomes do not appear to be viable in sites
where the plant was previously eradicated, even decades after
treatment. While shinnery oak has been germinated successfully in a
laboratory setting (Pettit 1986, pp. 1, 3), little documentation exists
that shinnery oak acorns successfully germinate in the wild (Wiedeman
1960, p. 22; Dhillion et al. 1994, p. 52). In addition, shinnery oak
produces an acorn crop in only about 3 of every 10 years (Pettit 1986,
p. 1).
While lesser prairie-chickens are found in Colorado and Kansas
where preferred habitats lack shinnery oak, the importance of shinnery
oak as a component of lesser prairie-chicken habitat has been
demonstrated by several studies (Fuhlendorf et al. 2002, pp. 624-626;
Bell 2005, pp. 15, 19-25). In a study conducted in west Texas, Haukos
and Smith (1989, p. 625) documented strong nesting avoidance by lesser
prairie-chickens of shinnery oak rangelands that had been treated with
the herbicide tebuthiuron. Similar
[[Page 73864]]
behavior was confirmed by three recent studies in New Mexico examining
aspects of lesser prairie-chicken habitat use, survival, and
reproduction relative to shinnery oak density and herbicide application
to control shinnery oak.
First, Bell (2005, pp. 20-21) documented strong thermal selection
for and dependency of lesser prairie-chicken broods on dominance of
shinnery oak in shrubland habitats. In this study, lesser prairie-
chicken hens and broods used sites within the shinnery oak community
that had a statistically higher percent cover and greater density of
shrubs. Within these sites, microclimate differed statistically between
occupied and random sites, and lesser prairie-chicken survival was
statistically higher in microhabitat that was cooler, more humid, and
less exposed to the wind. Survivorship was statistically higher for
lesser prairie-chickens that used sites with greater than 20 percent
cover of shrubs than for those choosing 10-20 percent cover; in turn,
survivorship was statistically higher for lesser prairie-chickens
choosing 10-20 percent cover than for those choosing less than 10
percent cover. Similarly, Copelin (1963, p. 42) stated that he believed
the reason lesser prairie-chickens occurred in habitats with shrubby
vegetation was due to the need for summer shade.
In a second study, Johnson et al. (2004, pp. 338-342) observed that
shinnery oak was the most common vegetation type in lesser prairie-
chicken hen home ranges. Hens were detected more often than randomly in
or near pastures that had not been treated to control shinnery oak.
Although hens were detected in both treated and untreated habitats in
this study, 13 of 14 nests were located in untreated pastures, and all
nests were located in areas dominated by shinnery oak. Areas
immediately surrounding nests also had higher shrub composition than
the surrounding pastures. This study suggested that herbicide treatment
to control shinnery oak adversely impacts nesting lesser prairie-
chicken.
Finally, a third study showed that over the course of 4 years and
five nesting seasons, lesser prairie-chicken in the core of occupied
range in New Mexico distributed themselves non-randomly among shinnery
oak rangelands treated and untreated with tebuthiuron (Patten et al.
2005a, pp. 1273-1274). Lesser prairie-chickens strongly avoided habitat
blocks treated with tebuthiuron but were not influenced by presence of
cattle grazing. Further, herbicide treatment explained nearly 90
percent of the variation in occurrence among treated and untreated
areas. Over time, radio-collared lesser prairie-chickens spent
progressively less time in treated habitat blocks, with almost no use
of treated pastures in the fourth year following herbicide application
(25 percent in 2001, 16 percent in 2002, 3 percent in 2003, and 1
percent in 2004).
In contrast, McCleery et al. (2007, pp. 2135-2136) argued that the
importance of shinnery oak habitats to lesser prairie-chickens has been
overemphasized, primarily based on occurrence of the species in areas
outside of shinnery oak dominated habitats. We agree that shinnery oak
may not be a rigorously required component of lesser prairie-chicken
habitat rangewide. However, we believe that shrubs are important to
lesser prairie-chickens. Recently, Timmer (2012, pp. 38, 73-74) found
that lesser prairie-chicken lek density peaked when approximately 50
percent of the landscape was composed of shrubland patches consisting
of shrubs less than 5 m (16 ft) tall and comprising at least 20 percent
of the total vegetation. Shrubs are an important component of suitable
habitat and where shinnery oak occurs, lesser prairie-chickens use it
both for food and cover. We believe that where shinnery oak
historically, and still currently, occurs, it provides suitable habitat
for lesser prairie-chickens. The loss of these habitats likely
contributed to observed population declines in lesser prairie-chickens.
Mixed-sand sagebrush and shinnery oak rangelands are well documented as
preferred lesser prairie-chicken habitat, and long-term stability of
shrubland landscapes has been shown to be particularly important to the
species (Woodward et al. 2001, p. 271).
On BLM lands, where the occurrence of the dunes sagebrush lizard
and lesser prairie-chicken overlaps, their Resource Management Plan
Amendment (RMPA) states that tebuthiuron may only be used in shinnery
oak habitat if there is a 500-m (1,600-ft) buffer around dunes, and
that no chemical treatments should occur in suitable or occupied dunes
sagebrush lizard habitat (BLM 2008, p. 4-22). In this RMPA (BLM 2008,
pp. 16-17), BLM will allow spraying of shinnery oak in lesser prairie-
chicken habitat where it does not overlap with the dunes sagebrush
lizard. Additionally, the New Mexico State Lands Office and private
land owners continue to use tebuthiuron to remove shinnery oak for
cattle grazing and other agricultural purposes (75 FR 77809, December
14, 2010). The NRCS's herbicide spraying has treated shinnery oak in at
least 39 counties within shinnery oak habitat (Peterson and Boyd 1998,
p. 4).
The BLM, through the Restore New Mexico program, also treats
mesquite with herbicides to restore grasslands to a more natural
condition by reducing the extent of brush. While some improvement in
livestock forage occurs, the areas are rested from grazing for two
growing seasons and no increase in stocking rate is allowed. Because
mesquite is not readily controlled by fire, herbicides often are
necessary to treat its invasion. The BLM has treated some 148,257 ha
(366,350 ac) and has plans to treat an additional 128,375 ha (317,220
ac). In order to treat encroaching mesquite, BLM aerially treats with a
mix of the herbicides Remedy (triclopyr) and Reclaim (clopyralid).
Although these chemicals are used to treat the adjacent mesquite, some
herbicide drift into shinnery oak habitats can occur during
application. Oaks are also included on the list of plants controlled by
Remedy, and one use for the herbicide is treatment specifically for
sand shinnery oak suppression, as noted on the specimen label (Dow
AgroSciences 2008, pp. 5, 7). While Remedy can be used to suppress
shinnery oak, depending on the concentration, the anticipated impacts
of herbicide drift into non-target areas are expected to be largely
short-term due to differences in application rates necessary for the
desired treatments. Forbs are also susceptible to Remedy, according to
the specimen label, and may be impacted by these treatments, at least
temporarily (Dow AgroSciences 2008, p. 2). Typically, shinnery oak and
mesquite occurrences don't overlap due to inherent preferences for
sandy versus tighter soils. Depending on the density of mesquite, these
areas may or may not be used by lesser prairie-chickens prior to
treatment.
Lacking germination of shinnery oak acorns, timely recolonization
of treated areas, or any established propagation or restoration method,
the application of tebuthiuron at rates approved for use in most States
can eliminate high-quality lesser prairie-chicken habitat. Large tracts
of shrubland communities are decreasing, and native shrubs drive
reproductive output for ground-nesting birds in shinnery oak rangelands
(Guthery et al. 2001, p. 116).
In summary, we conclude that the long-term to permanent removal of
shinnery oak is an ongoing threat to the lesser prairie-chicken in New
Mexico, Oklahoma, and Texas. Habitat in which shinnery oak is
permanently removed may fail to meet basic needs of the species, such
as foraging, nesting, predator avoidance, and
[[Page 73865]]
thermoregulation. Permanent conversion of shinnery oak and other types
of shrubland to other land uses contributes to habitat fragmentation
and poses a threat to population persistence.
Insecticides
To our knowledge, no studies have been conducted examining
potential effects of agricultural insecticide use on lesser prairie-
chicken populations. However, impacts from pesticides to other prairie
grouse have been documented. Of approximately 200 greater sage grouse
known to be feeding in a block of alfalfa sprayed with dimethoate, 63
were soon found dead, and many others exhibited intoxication and other
negative symptoms (Blus et al. 1989, p. 1139). Because lesser prairie-
chickens are known to selectively feed in alfalfa fields (Hagen et al.
2004, p. 72), the Service believes there may be cause for concern that
similar impacts could occur. Additionally some control efforts, such as
grasshopper suppression in rangelands by the USDA Animal and Plant
Health Inspection Service, treat economic infestations of grasshoppers
with insecticides. Treatment could cause reductions in insect
populations used by lesser prairie-chickens. However, in the absence of
more conclusive evidence, we do not currently consider application of
insecticides for most agricultural purposes to be a threat to the
species.
Altered Fire Regimes and Encroachment by Invasive Woody Plants
Preferred lesser prairie-chicken habitat is characterized by
expansive regions of treeless grasslands interspersed with patches of
small shrubs (Giesen 1998, pp. 3-4). Prior to extensive EuroAmerican
settlement, frequent fires and grazing by large, native ungulates
helped confine trees like Juniperus virginiana (eastern red cedar) to
river and stream drainages and rocky outcroppings. However, settlement
of the southern Great Plains altered the historical disturbance regimes
and contributed to habitat fragmentation and conversion of native
grasslands. The frequency and intensity of these disturbances directly
influenced the ecological processes, biological diversity, and
patchiness typical of Great Plains grassland ecosystems, which evolved
with frequent fire and ungulate herbivory and that provided ideal
habitat for lesser prairie-chickens (Collins 1992, pp. 2003-2005;
Fuhlendorf and Smeins 1999, pp. 732, 737).
Once these historical fire and grazing regimes were altered, the
processes which helped maintain extensive areas of grasslands ceased to
operate effectively. Following EuroAmerican settlement, fire
suppression allowed trees, like eastern red cedar, to begin invading or
encroaching upon neighboring grasslands. Increasing fire suppression
that accompanied settlement, combined with government programs
promoting eastern red cedar for windbreaks, erosion control, and
wildlife cover, increased availability of eastern red cedar seeds in
grassland areas (Owensby et al. 1973, p. 256). Once established, wind
breaks and cedar plantings for erosion control contribute to
fragmentation of the prairie landscape. Because eastern red cedar is
not well adapted to survive most grassland fires due to its thin bark
and shallow roots (Briggs et al. 2002b, p. 290), the lack of frequent
fire greatly facilitated encroachment by eastern red cedar. Once trees
began to invade these formerly treeless prairies, the resulting habitat
became increasingly unsuitable for lesser prairie-chickens.
Similar to the effects of artificial vertical structures, the
presence of trees causes lesser prairie-chickens to cease using areas
of otherwise suitable habitat. Woodward et al. (2001, pp. 270-271)
documented a negative association between landscapes with increased
woody cover and lesser prairie-chicken population indices. Similarly,
Fuhlendorf et al. (2002, p. 625) examined the effect of landscape
structure and change on population dynamics of lesser prairie-chicken
in western Oklahoma and northern Texas. They found that landscapes with
declining lesser prairie-chicken populations had significantly greater
increases in tree cover types (riparian, windbreaks, and eastern red
cedar encroachment) than landscapes with sustained lesser prairie-
chicken populations.
Tree encroachment into grassland habitats has been occurring for
numerous decades, but the extent has been increasing rapidly in recent
years. Tree invasion in native grasslands and rangelands has the
potential to render significant portions of remaining occupied habitat
unsuitable within the future. Once a grassland area has been colonized
by eastern red cedar, the trees are mature within 6 to 7 years and
provide a plentiful source of seed in which adjacent areas can readily
become infested. Although specific information documenting the extent
of eastern red cedar infestation within the historical range of the
lesser prairie-chicken is unavailable, limited information from
Oklahoma and portions of Kansas help demonstrate the significance of
this threat to lesser prairie-chicken habitat.
In Riley County, Kansas, within the tallgrass prairie region known
as the Flint Hills, the amount of eastern red cedar coverage increased
over 380 percent within a 21-year period (Price and Grabow 2010, as
cited in Beebe et al. 2010, p. 2). In another portion of the Flint
Hills of Kansas, transition from a tallgrass prairie to a closed canopy
(where tree canopy is dense enough for tree crowns to fill or nearly
fill the canopy layer so that light cannot reach the floor beneath the
trees) eastern red cedar forest occurred in as little as 40 years
(Briggs et al. 2002a, p. 581). Similarly, the potential for development
of a closed canopy (crown closure) in western Oklahoma is very high
(Engle and Kulbeth 1992, p. 304), and eastern red cedar encroachment in
Oklahoma is occurring at comparable rates. Estimates developed by NRCS
in Oklahoma revealed that some 121,406 ha (300,000 ac) a year are being
infested by eastern red cedar (Zhang and Hiziroglu 2010, p. 1033).
Stritzke and Bidwell (1989, as cited in Zhang and Hiziroglu 2010, p.
1033) estimated that the area infested by eastern red cedar increased
from over 600,000 ha (1.5 million ac) in 1950 to over 1.4 million ha
(3.5 million ac) by 1985. By 2002, the NRCS estimated that eastern red
cedar had invaded some 3.2 million ha (8 million ac) of prairie and
cross timbers habitat in Oklahoma (Drake and Todd 2002, p. 24). Eastern
red cedar encroachment in Oklahoma is expected to exceed 5 million ha
(12.6 million ac) by 2013 (Zhang and Hiziroglu 2010, p. 1033). While
the area infested by eastern red cedar in Oklahoma is not restricted to
the historical or occupied range of the lesser prairie-chicken, the
problem appears to be the worst in northwestern and southwestern
Oklahoma (Zhang and Hiziroglu 2010, p. 1032). Considering that
southwestern Kansas and the northeastern Texas panhandle have
comparable rates of precipitation, fire exclusion, and grazing pressure
as western Oklahoma, this rate of infestation is likely occurring in
many areas of occupied and historical lesser prairie-chicken range.
Eastern red cedar is not the only woody species known to be
encroaching in prairies used by lesser prairie-chicken. Within the
southern- and western-most portions of the historical range in New
Mexico and Texas, mesquite is the most common woody invader within
these grasslands and can preclude nesting and brood use by lesser
prairie-chickens (Riley 1978, p. vii). Mesquite is an ideal woody
invader in grassland habitats due to its ability to
[[Page 73866]]
produce abundant, long-lived seeds that can germinate and establish in
a variety of soil types and moisture and light regimes (Archer et al.
1988, p. 123). Much of the remaining historical grasslands and
rangelands in the southern portions of the Texas panhandle have been
invaded by mesquite.
Although the precise extent and rate of mesquite invasion is
difficult to determine rangewide, the ecological process by which
mesquite and related woody species invades these grasslands has been
described by Archer et al. (1988, pp. 111-127) for the Rio Grande
Plains of Texas. In this study, once a single mesquite tree colonized
an area of grassland, this plant acted as the focal point for seed
dispersal of woody species that previously were restricted to other
habitats (Archer et al. 1988, p. 124). Once established, factors such
as overgrazing, reduced fire frequency, and drought interacted to
enable mesquite and other woody plants to increase in density and
stature on grasslands (Archer et al. 1988, p. 112). On their study site
near Alice, Texas, they found that woody plant cover significantly
increased from 16 to 36 percent between 1941 and 1983, likely
facilitated by heavy grazing (Archer et al. 1988, p. 120). The study
site had a history of heavy grazing since the late 1800s. However,
unlike eastern red cedar, mesquite is not as readily controlled by
fire. Wright et al. (1976, pp. 469-471) observed that mesquite
seedlings older than 1.5 years were difficult to control with fire
unless they had first been top killed with an herbicide, and the
researchers observed that survival of 2- to 3-year-old mesquite
seedlings was as high as 80 percent even following very hot fires.
Prescribed burning is often the best method to control or preclude
tree invasion of native grassland and rangeland. However, burning of
native prairie is often perceived by landowners to be destructive to
rangelands, undesirable for optimizing cattle production, and likely to
create wind erosion or ``blowouts'' in sandy soils. Often, prescribed
fire is employed only after significant invasion has already occurred
and landowners consider forage production for cattle to have
diminished. Consequently, fire suppression is common, and relatively
little prescribed burning occurs on private land. Additionally, in
areas where grazing pressure is heavy and fuel loads are reduced, a
typical grassland fire may not be intense enough to eradicate eastern
red cedar (Briggs et al. 2002a, p. 585; Briggs et al. 2002b, pp. 293;
Bragg and Hulbert 1976, p. 19). Briggs et al. (2002a, p. 582) found
that grazing reduced potential fuel loads by 33 percent, and the
reduction in fuel load significantly reduced mortality of eastern red
cedar post-fire. While establishment of eastern red cedar reduces the
abundance of herbaceous grassland vegetation, grasslands have a
significant capacity to recover rapidly following cedar control efforts
(Pierce and Reich 2010, p. 248). However, both Van Auken (2000, p. 207)
and Briggs et al. (2005, p. 244) stated that expansion of woody
vegetation into grasslands will continue to pose a threat to grasslands
well into the future.
In summary, invasion of native grasslands by certain woody species
like eastern red cedar cause otherwise suitable habitats to no longer
be used by lesser prairie-chickens and contribute to fragmentation of
native grassland habitats. We expect that efforts to control invasive
woody species like eastern red cedar and mesquite will continue but
that treatment efforts likely will be insufficient to keep pace with
rates of expansion, especially when considering the environmental
changes resulting from climate change (see discussion below).
Therefore, encroachment by invasive woody plants contributes to further
habitat fragmentation and poses a threat to population persistence.
Climate Change
The effects of ongoing and projected changes in climate are
appropriate for consideration in our analyses conducted under the Act.
The Intergovernmental Panel on Climate Change (IPCC) has concluded that
warming of the climate in recent decades is unequivocal, as evidenced
by observations of increases in global average air and ocean
temperatures, widespread melting of snow and ice, and rising global sea
level (Solomon et al. 2007, p. 1). The term ``climate'', as defined by
the IPCC, refers to the mean and variability of different types of
weather conditions over time, with 30 years being a typical period for
such measurements, although shorter or longer periods also may be used
(IPCC 2007a, p. 78). The IPCC defines the term ``climate change'' to
refer to a change in the mean or variability of one or more measures of
climate (e.g., temperature or precipitation) that persists for an
extended period, typically decades or longer, whether the change is due
to natural variability, human activity, or both (IPCC 2007a, p. 78).
Scientific measurements spanning several decades demonstrate that
changes in climate are occurring and that the rate of change has been
faster since the 1950s. Examples include warming of the global climate
system and substantial increases in precipitation in some regions of
the world and decreases in other regions. (For these and other
examples, see IPCC 2007a, p. 30; and Solomon et al. 2007, pp. 35-54,
82-85). Results of scientific analyses presented by the IPCC show that
most of the observed increase in global average temperature since the
mid-20th century cannot be explained by natural variability in climate,
and is ``very likely'' (defined by the IPCC as 90 percent or higher
probability) due to the observed increase in greenhouse gas
concentrations in the atmosphere as a result of human activities,
particularly carbon dioxide emissions from use of fossil fuels (IPCC
2007a, pp. 5-6 and figures SPM.3 and SPM.4; Solomon et al. 2007, pp.
21-35). Further confirmation of the role of greenhouse gasses comes
from analyses by Huber and Knutti (2011, p. 4), who concluded it is
extremely likely that approximately 75 percent of global warming since
1950 has been caused by human activities.
Scientists use a variety of climate models, which include
consideration of natural processes and variability, as well as various
scenarios of potential levels and timing of greenhouse gas emissions,
to evaluate the causes of changes already observed and to project
future changes in temperature and other climate conditions (e.g., Meehl
et al. 2007, entire; Ganguly et al. 2009, pp. 11555, 15558; Prinn et
al. 2011, pp. 527, 529). All combinations of models and emissions
scenarios yield very similar projections of increases in the most
common measure of climate change, average global surface temperature
(commonly known as global warming), until about 2030. Although
projections of the intensity and rate of warming differ after about
2030, the overall trajectory of all the projections is one of increased
global warming through the end of this century, even for the
projections based on scenarios that assume that greenhouse gas
emissions will stabilize or decline. Thus, there is strong scientific
support for projections that warming will continue through the 21st
century and that the extent and rate of change will be influenced
substantially by the extent of greenhouse gas emissions (IPCC 2007a,
pp. 44-45; Meehl et al. 2007, pp. 760-764 and 797-811; Ganguly et al.
2009, pp. 15555-15558; Prinn et al. 2011, pp. 527, 529). (See IPCC
2007b, p. 8, for a summary of other global projections of climate-
related changes, such as frequency of heat waves and changes in
precipitation. Also, see IPCC (2012, entire) for a summary of
observations
[[Page 73867]]
and projections of extreme climate events.)
Various changes in climate may have direct or indirect effects on
species. These effects may be positive, neutral, or negative, and they
may change over time, depending on the species and other relevant
considerations, such as interactions of climate with other variables
(e.g., habitat fragmentation) (IPCC 2007a, pp. 8-14, 18-19).
Identifying likely effects often involves aspects of climate change
vulnerability analysis. Vulnerability refers to the degree to which a
species (or system) is susceptible to, and unable to cope with, adverse
effects of climate change, including climate variability and extremes.
Vulnerability is a function of the type, intensity, and rate of climate
change and variation to which a species is exposed, its sensitivity,
and its adaptive capacity (IPCC 2007a, p. 89; see also Glick et al.
2011, pp. 19-22). There is no single method for conducting such
analyses that applies to all situations (Glick et al. 2011, p. 3). We
use our expert judgment and appropriate analytical approaches to weigh
relevant information, including uncertainty, in our consideration of
various aspects of climate change.
As is the case with all stressors that we assess, even if we
conclude that a species is currently affected or is likely to be
affected in a negative way by one or more climate-related impacts, it
does not necessarily follow that the species meets the definition of an
``endangered species'' or a ``threatened species'' under the Act. If a
species is listed as endangered or threatened, knowledge regarding the
vulnerability of the species to, and known or anticipated impacts from,
climate-associated changes in environmental conditions can be used to
help devise appropriate strategies for its recovery.
Some species of grouse have already exhibited significant and
measurable negative impacts attributed to climate change. For example,
capercaillie grouse in Scotland have been shown to nest earlier than in
historical periods in response to warmer springs yet reared fewer
chicks (Moss et al. 2001, p. 58). The resultant lowered breeding
success as a result of the described climactic change was determined to
be the major cause of the decline of the Scottish capercaillie (Moss et
al. 2001, p. 58).
Within the Great Plains, average temperatures have increased and
projections indicate this trend will continue over this century (Karl
et al. 2009, p. 1). Precipitation within the southern portion of the
Great Plains is expected to decline, with extreme events such as heat
waves, sustained droughts, and heavy rainfall becoming more frequent
(Karl et al. 2009, pp. 1-2). Seager et al. (2007, pp. 1181, 1183-1184)
suggests that `dust bowl' conditions of the 1930s could be the new
climatology of the American Southwest, with droughts being much more
extreme than most droughts on record.
As a result of changing conditions, the distribution and abundance
of grassland bird species will be affected (Niemuth et al. 2008, p.
220). Warmer air and surface soil temperatures and decreased soil
moisture near nest sites have been correlated with lower survival and
recruitment in some ground-nesting birds such as the bobwhite quail
(Guthery et al. 2001, pp. 113-115) and the lesser prairie-chicken (Bell
2005, pp. 16, 21). On average, lesser prairie-chickens avoid sites that
were hotter, drier, and more exposed to the wind (Patten et al. 2005a,
p. 1275). Specific to lesser prairie chickens, an increased frequency
of heavy rainfall events could affect their reproductive success
(Lehmann 1941 as cited in Peterson and Silvy 1994, p. 223; Morrow et
al. 1996, p. 599) although the deleterious effects of increased
precipitation have been disputed by Peterson and Silvy (1994, pp. 227-
228).
Additionally, more extreme droughts, in combination with existing
threats, will have detrimental implications for the lesser prairie-
chicken (see Drought discussion in ``Extreme Weather Events'' below).
Boal et al. (2010, p. 4) suggests that increased temperatures, as
projected by climate models, may lead to egg death or nest abandonment
of lesser prairie-chickens. Furthermore, the researchers suggest that
if lesser prairie-chickens shift timing of reproduction (to later in
the year) to compensate for lower precipitation, then temperature
impacts could be exacerbated.
In 2010, the Service evaluated three different climate change
vulnerability models to determine their usefulness as potential tools
for examining the effects of climate change (U.S. Environmental
Protection Agency 2009, draft review; NatureServe 2010; USDA Rocky
Mountain Research Station 2010, in development). Outcomes from our
assessment of each of these models for the lesser prairie-chicken
suggested that the lesser prairie-chicken is highly vulnerable to, and
will be negatively affected by, projected climate change. Factors
identified in the models that increase the vulnerability of the lesser
prairie chicken to climate change include, but are not limited to the
following: (1) The species' limited distribution and relatively small
declining population, (2) the species' physiological sensitivity to
temperature and precipitation change, (3) specialized habitat
requirements, and (4) the overall limited ability of the habitats
occupied by the species to shift at the same rate as the species in
response to climate change.
Increasing temperatures, declining precipitation, and extended,
severe drought events would be expected to adversely alter habitat
conditions, reproductive success, and survival of the lesser prairie-
chicken. While populations of lesser prairie-chicken in the
southwestern part of their range are likely to be most acutely
affected, populations throughout their range into Colorado and Kansas
likely will be impacted as well. Based on current climate change
projections of increased temperatures, decreased rainfall, and an
increase of severe events such as drought and rainfall within the
southern Great Plains, the lesser prairie-chicken is likely to be
adversely impacted by the effects of climate changes, especially when
considered in combination with other known threats and the anticipated
vulnerability of the species.
Additionally, many climate scientists predict that numerous species
will shift their geographical distributions in response to warming of
the climate (McLaughlin et al. 2002, p. 6070). In mountainous areas,
species may shift their range altitudinally, in flatter areas, ranges
may shift lattitudinally (Peterson 2003, p. 647). Such shifts may
result in localized extinctions over portions of the range, and, in
other portions of their distributions, the occupied range may expand,
depending upon habitat suitability. Changes in geographical
distributions can vary from subtle to more dramatic rearrangements of
occupied areas (Peterson 2003, p. 650). Species occupying flatland
areas such as the Great Plains generally were expected to undergo more
severe range alterations than those in montane areas (Peterson 2003, p.
651). Additionally, populations occurring in fragmented habitats can be
more vulnerable to effects of climate change and other threats,
particularly for species with limited dispersal abilities (McLaughlin
et al. 2002, p. 6074). Species inhabiting relatively flat lands will
require corridors that allow north-south movements, presuming suitable
habitat exists in these areas. Where existing occupied range is bounded
by areas of unsuitable habitat, the species' ability to move into
suitable areas is reduced and the amount of occupied habitat could
shrink accordingly. In some cases, particularly when natural movement
has a high probability of failure, assisted migration
[[Page 73868]]
may be necessary to ensure populations persist ((McLachlan et al. 2007,
entire).
We do not currently know how the distribution of lesser prairie-
chickens may change geographically under anticipated climate change
scenarios. Certainly the presence of suitable grassland habitats
created under CRP may play a key role in how lesser prairie-chickens
respond to the effects of climate change. Additionally, species that
are insectivorous throughout all or a portion of their life cycle, like
the lesser prairie-chicken, may have increased risks where a
phenological mismatch exists between their biological needs and shifts
in insect abundance due to vulnerability of insects to changes in
thermal regimes (Parmesan 2006, pp. 638, 644, 657; McLachlan et al.
2011. p. 5). McLachlan et al. (2011, pp. 15, 26) predicted that lesser
prairie-chicken carrying capacity would decline over the next 60 years
due to climate change, primarily the result of decreased vegetation
productivity (reduced biomass); however, they could not specifically
quantify the extent of the decline. They estimated the current carrying
capacity to be 49,592 lesser prairie-chickens (McLachlan et al. 2011,
p. 25). Based on their analysis, McLachlan et al. (2011, p. 29)
predicted that the lesser prairie-chicken may be facing significant
challenges to long-term survival over the next 60 years due to climate-
related changes in native grassland habitat. We anticipate that
climate-induced changes in ecosystems, including grassland ecosystems
used by lesser prairie-chickens, coupled with ongoing habitat loss and
fragmentation will interact in ways that will amplify the individual
negative effects of these and other threats identified in this proposed
rule (Cushman et al. 2010, p. 8).
Extreme Weather Events
Weather-related events such as drought and hail storms influence
habitat quality or result in direct mortality of lesser prairie-
chicken. Although hail storms typically only have a localized effect,
the effects of snow storms and drought can often be more wide-spread
and can affect considerable portions of the occupied range.
Drought--Drought is considered a universal ecological driver across
the Great Plains (Knopf 1996, p. 147). Annual precipitation within the
Great Plains is considered highly variable (Wiens 1974a, p. 391) with
prolonged drought capable of causing local extinctions of annual forbs
and grasses within stands of perennial species, and recolonization is
often slow (Tilman and El Haddi 1992, p. 263). Net primary production
in grasslands is strongly influenced by annual precipitation patterns
(Sala et al. 1988, pp. 42-44; Weltzin et al. 2003. p. 944) and drought,
in combination with other factors, is thought to limit the extent of
shrubby vegetation within grasslands (Briggs et al. 2005, p. 245).
Grassland bird species, in particular, are impacted by climate extremes
such as extended drought, which acts as a bottleneck that allows only a
few species to survive through the relatively harsh conditions (Wiens
1974a, pp. 388, 397; Zimmerman 1992, p. 92). Drought also can influence
many of the factors previously addressed in this proposed rule, such as
exaggerating and prolonging the effect of fires and overgrazing.
The Palmer Drought Severity Index (Palmer 1965, entire) is a
measure of the balance between moisture demand (evapotranspiration
driven by temperature) and moisture supply (precipitation) and is
widely used as an indicator of the intensity of drought conditions
(Alley 1984, entire). This index is standardized according to local
climate (i.e., climate divisions established by the National Oceanic
and Atmospheric Administration) and is most effective in determining
magnitude of long-term drought occurring over several months. The index
uses zero as normal with drought shown in terms of negative numbers.
Positive numbers imply excess precipitation.
The droughts of the 1930s and 1950s are some of the most severe on
record (Schubert et al. 2004, p. 485). During these periods, the Palmer
Drought Severity Index exceeded negative 4 and 5 in many parts of the
Great Plains, which would be classified as extreme to exceptional
drought. The drought that impacted much of the occupied lesser prairie-
chicken range in 2011 also was classified as severe to extreme,
particularly during the months of May through August (National Climatic
Data Center 2012). This time period is significant because the period
of May through September generally overlaps the lesser prairie-chicken
nesting and brood-rearing season. Review of the available records for
the Palmer Drought Severity Index during the period from May through
September 2011, for many of the climate divisions within the lesser
prairie-chicken occupied range, revealed that the index exceeded
negative 4 over most of the occupied range. Climate division 4 in
westcentral Kansas was the least impacted by drought in 2011, with a
Palmer Drought Severity Index of negative 2.29. The most severe drought
occurred in the Texas panhandle.
Based on an evaluation of the Palmer Drought Severity Index for May
through July of 2012, several of the climate divisions which overlap
the occupied range are currently experiencing extreme to exceptional
drought. Colorado, New Mexico, and Texas are experiencing the worst
conditions, based on index values varying from a low of negative 5.8 in
Colorado to a high index value of negative 4.1 in Texas and New Mexico.
Drought is least severe in Oklahoma, although climate division 4 is
currently at negative 2.4. Index values for Kansas are in the severe
range and vary from negative 2.7 to negative 3.3. Such persistent
drought conditions will impact vegetative cover for nesting and can
reduce insect populations needed by growing chicks. Additionally,
drought impacts forage needed by livestock and continued grazing under
such conditions can rapidly degrade native rangeland.
During times of severe to extreme drought, suitable livestock
forage may become unavailable or considerably reduced due to a loss of
forage production on existing range and croplands. Through provisions
of the CRP, certain lands under existing contract can be used for
emergency haying and grazing, provided specific conditions are met, to
help relieve the impacts of drought by temporarily providing livestock
forage. Typically, emergency haying and grazing is allowed only on
those lands where appropriate Conservation Practices (CP), already
approved for managed haying and grazing, have been applied to the CRP
field. For example, CRP fields planted to either introduced grasses
(CP-1) or native grasses (CP-2) are eligible. However, during the
widespread, severe drought of 2012, some additional CPs that were not
previously eligible to be hayed or grazed were approved for emergency
haying and grazing only during 2012. Typically any approved emergency
haying or grazing must occur outside of the primary nesting season. The
duration of the emergency haying can be no longer than 60 calendar
days, and the emergency grazing period cannot extend beyond 90 calendar
days, and both must conclude by September 30th of the current growing
season. Generally areas that were emergency hayed or grazed in 1 year
are not eligible the following 2 years. Other restrictions also may
apply.
In most years, the amounts of land that are hayed or grazed are
low, typically less than 15 percent of eligible acreage, likely because
the producer must take a 25 percent reduction in the annual rental
payment, based on the amount of lands that are hayed or
[[Page 73869]]
grazed. However, during the 2011 drought, requests for emergency haying
and grazing were larger than previously experienced. For example, in
Oklahoma, more than 103,200 ha (255,000 ac) or roughly 30 percent of
the available CRP lands statewide were utilized. Within those counties
that encompass the occupied range, almost 55,400 ha (137,000 ac) or
roughly 21 percent of the available CRP in those counties were hayed or
grazed. In Kansas, there were almost 95,900 ha (237,000 ac) under
contract for emergency haying or grazing within the occupied range. The
number of contracts for emergency haying and grazing within occupied
range is about 18 percent of the total number of contracts within
occupied range. Within New Mexico in 2011, there were approximately
25,900 ha (64,100 ac) under contract for emergency grazing, 97 percent
of which were in counties that are either entirely or partially within
the historical range of the lesser prairie-chicken. Texas records do
not differentiate between managed CRP grazing and haying and that
conducted under emergency provisions. Within the historical range in
2011, some 65 counties had CRP areas that were either hayed or grazed.
The average percent of areas used was 22 percent. Within the occupied
counties, the average percent grazed was the same, 22 percent.
As of the close of July 2012, the entire occupied and historical
range of the lesser prairie-chicken was classified as abnormally dry or
worse (Farm Service Agency 2012, p. 14). The abnormally dry category
roughly corresponds to a Palmer Drought Index of minus 1.0 to minus
1.9. Based on new provisions announced by USDA on July 23, 2012, the
entire historical and currently occupied range of the lesser prairie-
chicken is eligible for emergency haying and grazing. Additionally, the
reduction in the annual rental payment has been reduced from 25 percent
to 10 percent. Although the actual extent of emergency haying and
grazing that occurs will not be known until after September 30, 2012,
we expect that the effect will be significant. The extent of emergency
haying in the 2012 season and its impact on lesser prairie-chicken
habitat will be analyzed as part of our final listing determination. In
many instances, areas that were grazed or hayed under the emergency
provisions of 2011 have not recovered due to the influence of the
ongoing drought. Additionally, current provisions will allow additional
fields to be eligible for emergency haying and grazing that have
previously not been eligible, including those classified as rare and
declining habitat (CP-25). Conservation Practice 25 provides for very
specific habitat components beneficial to ground-nesting birds such as
lesser prairie-chickens. The overall extent of relief provided to
landowners could result in more widespread implementation of the
emergency provisions than has been observed in previous years.
Widespread haying and grazing of CRP under drought conditions may
compromise the ability of these grasslands to provide year-round escape
cover and thermal cover during winter, at least until normal
precipitation patterns return (see sections ``Summary of Recent and
Ongoing Conservation Actions'' and ``Conservation Reserve Program'' for
additional information related to CRP).
Although the lesser prairie-chicken has adapted to drought as a
component of its environment, drought and the accompanying harsh,
fluctuating conditions have influenced lesser prairie-chicken
populations. Following extreme droughts of the 1930s and 1950s, lesser
prairie-chicken population levels declined and a decrease in their
overall range was observed (Lee 1950, p. 475; Schwilling 1955, pp. 5-6;
Hamerstrom and Hamerstrom 1961, p. 289; Copelin 1963, p. 49; Crawford
1980, pp. 2-5; Massey 2001, pp. 5, 12; Hagen and Giessen 2005,
unpaginated; Ligon 1953 as cited in New Mexico Lesser Prairie Chicken/
Sand Dune Lizard Working Group 2005, p. 19). More recently, a reduction
in lesser prairie-chicken population indices was documented after
drought conditions in 2006 followed by severe winter conditions in 2006
and early 2007. For example, Rodgers (2007b, p. 3) stated that lesser
prairie-chicken lek indices from surveys conducted in Hamilton County,
Kansas, declined by nearly 70 percent from 2006 levels and were the
lowest on record. In comparison to the 2011 drought, the Palmer Drought
Severity Index for the May through September period in Kansas during
the 2006 drought was minus 2.83 in climate division 4 and minus 1.51 in
climate division 7. Based on the Palmer Drought Severity Index, drought
conditions in 2011 were slightly worse than those observed in 2006.
Drought impacts the lesser prairie-chicken through several
mechanisms. Drought affects seasonal growth of vegetation necessary to
provide suitable nesting and roosting cover, food, and opportunity for
escape from predators (Copelin 1963, pp. 37, 42; Merchant 1982, pp. 19,
25, 51; Applegate and Riley 1998, p. 15; Peterson and Silvy 1994, p.
228; Morrow et al. 1996, pp. 596-597). Lesser prairie-chicken home
ranges will temporarily expand during drought years (Copelin 1963, p.
37; Merchant 1982, p. 39) to compensate for scarcity in available
resources. During these periods, the adult birds expend more energy
searching for food and tend to move into areas with limited cover in
order to forage, leaving them more vulnerable to predation and heat
stress (Merchant 1982, pp. 34-35; Flanders-Wanner et al. 2004, p. 31).
Chick survival and recruitment may also be depressed by drought
(Merchant 1982, pp. 43-48; Morrow 1986, p. 597; Giesen 1998, p. 11;
Massey 2001, p. 12), which likely affects population trends more than
annual changes in adult survival (Hagen 2003, pp. 176-177). Drought-
induced mechanisms affecting recruitment include decreased
physiological condition of breeding females (Merchant 1982, p. 45);
heat stress and water loss of chicks (Merchant 1982, p. 46); and
effects to hatch success and juvenile survival due to changes in
microclimate, temperature, and humidity (Patten et al. 2005a, pp. 1274-
1275; Bell 2005, pp. 20-21; Boal et al. 2010, p. 11). Precipitation, or
lack thereof, appears to affect lesser prairie-chicken adult population
trends with a potential lag effect (Giesen 2000, p. 145). That is, rain
in one year promotes more vegetative cover for eggs and chicks in the
following year, which enhances their survival.
Although lesser prairie-chickens have persisted through droughts in
the past, the effects of such droughts are exacerbated by 19th-21st
century land use practices such as heavy grazing, overutilization, and
land cultivation (Merchant 1982, p. 51; Hamerstrom and Hamerstrom 1961,
pp. 288-289; Davis et al. 1979, p. 122; Taylor and Guthery 1980a, p.
2), which have altered and fragmented existing habitats. In past
decades, fragmentation of lesser prairie-chicken habitat likely was
less extensive than current conditions, and connectivity between
occupied habitats was more prevalent, allowing populations to recover
more quickly. As lesser prairie-chicken populations decline and become
more fragmented, their ability to rebound from prolonged drought is
diminished. This reduced ability to recover from drought is
particularly concerning given that future climate projections suggest
that droughts will only become more severe. Projections based on an
analysis using 19 different climate models revealed that southwestern
North America, including the entire historical range of the lesser
prairie-chicken, will consistently become drier throughout
[[Page 73870]]
the 21st century (Seager et al. 2007, p. 1181). Severe droughts should
continue into the future, particularly during persistent La Ni[ntilde]a
events, but they are anticipated to be more severe than most droughts
on record (Seager et al. 2007, pp. 1182-1183).
Storms--Very little published information is available on the
effects of certain isolated weather events, like storms, on lesser
prairie-chicken. However, hail storms are known to cause mortality of
prairie grouse, particularly during the spring nesting season. Fleharty
(1995, p. 241) provides an excerpt from the May 1879 Stockton News that
describes a large hailstorm near Kirwin, Kansas, as responsible for
killing prairie-chickens (likely greater prairie-chicken) and other
birds by the hundreds. In May of 2008, a hailstorm was known to have
killed six lesser prairie-chickens in New Mexico. Although such
phenomena are undoubtedly rare, the effects can be significant,
particularly if they occur during the nesting period. We are especially
interested in documenting the occurrence and significance of such
events on the lesser prairie-chicken.
A severe winter snowstorm in 2006, centered over southeastern
Colorado, resulted in heavy snowfall, no cover, and little food in
southern Kiowa, Prowers, and most of Baca Counties for over 60 days.
The storm was so severe that more than 10,000 cattle died in Colorado
alone from this event, in spite of the efforts of National Guard and
other flight missions that used cargo planes and helicopters to drop
hay to stranded cattle (Che et al. 2008, pp. 2, 6). Lesser prairie-
chicken numbers in Colorado experienced a 75 percent decline from 2006
to 2007, from 296 birds observed to only 74. Active leks also declined
from 34 leks in 2006 to 18 leks in 2007 (Verquer 2007, p. 2). Most
strikingly, no active leks have been detected since 2007 in Kiowa
County, which had six active leks in the several years prior to the
storm. The impacts of the severe winter weather, coupled with drought
conditions observed in 2006, probably account for the decline in the
number of lesser prairie-chickens observed in 2007 in Colorado (Verquer
2007, pp. 2-3).
In summary, extreme weather events can have a significant impact on
individual populations of lesser prairie-chickens. These impacts are
especially significant in considering the status of the species as a
whole if the impacted population is isolated from individuals in other
nearby populations that may be capable of recolonizing or supplementing
the impacted population.
Wind Power and Energy Transmission Operation and Development
Wind power is a form of renewable energy that is increasingly being
used to meet electricity demands in the United States. The U.S. Energy
Information Administration has estimated that the demand for
electricity in the United States will grow by 39 percent between 2005
and 2030 (U.S. Department of Energy (DOE) 2008, p. 1). Wind energy,
under one scenario, would provide 20 percent of the United States'
estimated electricity needs by 2030 and require at least 250 gigawatts
of additional land-based wind power capacity to achieve predicted
levels (DOE 2008, pp. 1, 7, 10). The forecasted increase in production
would require some 125,000 turbines based on the existing technology
and equipment in use and assuming a turbine has a generating capacity
of 2 megawatts (MW). Achieving these levels also would require
expansion of the current electrical transmission system. Financial
incentives, including grants and tax relief, are available to help
encourage development of renewable energy sources.
Wind farm development begins with site monitoring and collection of
meteorological data to characterize the available wind regime. Turbines
are installed after the meteorological data indicate appropriate siting
and spacing. The tubular towers of most commercial, utility-scale
onshore wind turbines are between 65 m (213 ft) and 100 m (328 ft)
tall. The most common system uses three rotor blades and can have a
diameter of as much as 100 m (328 ft). The total height of the system
is measured when a turbine blade is in the 12 o'clock position and will
vary depending on the length of the blade. With blades in place, a
typical system will easily exceed 100 m (328 ft) in height. A wind farm
will vary in size depending on the size of the turbines and amount of
land available. Typical wind farm arrays consist of 30 to 150 towers
each supporting a single turbine. The individual permanent footprint of
a single turbine unit, about 0.3 to 0.4 ha (0.75 to 1 ac), is
relatively small in comparison with the overall footprint of the entire
array (DOE 2008, pp. 110-111). Spacing between each turbine is usually
5 to 10 rotor diameters to avoid interference between turbines. Roads
are necessary to access the turbine sites for installation and
maintenance. One or more substations, where the generated electricity
is collected and transmitted, also may be built depending on the size
of the wind farm. The service life of a single turbine is at least 20
years (DOE 2008, p. 16).
Siting of commercially viable wind energy developments is largely
based on wind intensity and consistency, and requires the ability to
transmit generated power to the users. Any discussion of the effects of
wind energy development on the lesser prairie-chicken also must take
into consideration the influence of the transmission lines critical to
distribution of the energy generated by wind turbines. Transmission
lines can traverse long distances across the landscape and can be both
above ground and underground. Most of the impacts associated with
transmission lines are with the aboveground systems. Support structures
vary in height depending on the size of the line. Most high-voltage
powerline towers are 30 to 38 m (98 to 125 ft) high but can be higher
if the need arises. Local distribution lines are usually much shorter
in height but can still contribute to fragmentation of the landscape.
Financial investment in the transmission of electrical power has been
steadily climbing since the late 1990s and includes not only the cost
of maintaining the existing system but also includes costs associated
with increasing reliability and development of new transmission lines
(DOE 2008, p. 94). Manville (2005, p. 1052) reported that there are at
least 804,500 km (500,000 mi) of transmission lines (lines carrying
greater than 115 kilovolts (kV)) within the United States. Recent
transmission-related activities within the historical range include the
creation of Competitive Renewable Energy Zones in Texas and the ``X
plan'' under consideration by the Southwest Power Pool.
All 5 lesser prairie-chicken States are within the top 12 States
nationally for potential wind capacity, with Texas ranking second for
potential wind energy capacity and Kansas ranking third (American Wind
Energy Association 2012b, entire). The potential for wind development
within the historical range of the lesser prairie-chicken is apparent
from the wind potential estimates developed by the DOE's National
Renewable Energy Laboratory and AWS Truewind. These estimates present
the predicted mean annual wind speeds at a height of 80 m (262 ft).
Areas with an average wind speed of 6.5 m/s (21.3 ft/s) and greater at
a height of 80 m (262 ft) are generally considered to have a suitable
wind resource for development. All of the historical and current range
of the lesser prairie-chicken occurs in areas determined to have 6.5 m/
s (21.3 ft/s) or higher average windspeed (DOE National Renewable
Energy Laboratory
[[Page 73871]]
2010b, p. 1). The vast majority of the occupied range lies within areas
of 7.5 m/s (24.6 ft/s) or higher windspeeds.
Wind energy developments already exist within the historical range
of the lesser prairie-chicken, some of which have impacted occupied
habitat. The 5 lesser prairie-chicken States are all within the top 20
States nationally for installed wind capacity (American Wind Energy
Association 2012a, p. 6). By the close of 1999, the installed capacity,
in MW, of wind power facilities within the five lesser prairie-chicken
States was 209 MW; the majority, 184 MW, was provided by the State of
Texas (DOE National Renewable Energy Laboratory 2010a, p. 1). At the
close of the first quarter of 2012, the installed capacity within the
five lesser prairie-chicken States had grown to 16,516 MW (American
Wind Energy Association 2012a, p. 7). Although not all of this
installed capacity is located within the historical range of the lesser
prairie-chicken, and includes offshore wind projects in Texas, there is
considerable overlap between the historical range and those areas
having good to excellent wind potential, as determined by the DOE's
National Renewable Energy Laboratory (DOE National Renewable Energy
Laboratory 2010b, p. 1). Areas having good to excellent wind potential
represent the highest priority sites for wind power development.
Within the estimated occupied range in Colorado, existing wind
projects are located in Baca, Bent, and Prowers Counties. Colorado's
installed wind capacity grew by 39 percent in 2011 (American Wind
Energy Association 2012b, entire). In Kansas, Barber, Ford, Gray,
Kiowa, and Wichita Counties have existing wind projects. Kansas is
expected to double their existing capacity in 2012 and leads the United
States with the most wind power under construction (American Wind
Energy Association 2012b, entire). Curry, Roosevelt, and Quay Counties
in the New Mexico portion of the estimated occupied range currently
have operating wind projects. There are some 14,136 MW (roughly 5,654
2.5 MW turbines) in the queue awaiting construction (American Wind
Energy Association 2012b, entire). In Oklahoma, Custer, Dewey, Harper,
Roger Mills, and Woodward Counties have existing wind farms. Some 393
MW are under construction and there is another 14,667 MW in the queue
awaiting construction. In Texas, no wind farms have been constructed
within the currently occupied counties (American Wind Energy
Association 2012b, entire).
Most published literature on the effects of wind development on
birds focuses on the risks of collision with towers or turbine blades.
Until recently, there was very little published research specific to
the effects of wind turbines and transmission lines on prairie grouse
and much of that focuses on avoidance of the infrastructure associated
with renewable energy development (see previous discussion on vertical
structures in the ``Causes of Habitat Fragmentation Within Lesser
Prairie-Chicken Range'' section above and discussion that follows). We
suspect that many wind power facilities are not monitored consistently
enough to detect collision mortalities and the observed avoidance of
and displacement influenced by the vertical infrastructure observed in
prairie grouse likely minimizes the opportunity for such collisions to
occur. However, Vodenal et al. (2011, unpaginated) has observed both
greater prairie-chickens and plains sharp-tailed grouse (Tympanuchus
phasianellus jamesi) lekking near the Ainsworth Wind Energy Facility in
Nebraska since 2006. The average distance of the observed display
grounds to the nearest wind turbine tower was 1,430 m (4,689 ft) for
greater prairie-chickens and 1,178 m (3,864 ft) for sharp-tailed
grouse.
While both lesser and greater prairie-chickens appear to be more
tolerant of these structures than some other species of prairie grouse,
Hagen (2004, p. 101) cautions that occurrence near these structures may
be due to strong site fidelity or continued use of suitable habitat
remnants and that these populations actually may not be able to sustain
themselves without immigration from surrounding populations (i.e.,
population sink).
Currently, we have no documentation of any collision-related
mortality in wind farms for lesser prairie-chickens. Similarly, no
deaths of gallinaceous birds (upland game birds) were reported in a
comprehensive review of avian collisions and wind farms in the United
States; the authors hypothesized that the average tower height and
flight height of grouse minimized the risk of collision (Erickson et
al. 2001, pp. 8, 11, 14, 15). However, Johnson and Erickson (2011, p.
17) monitored commercial scale wind farms in the Columbia Plateau of
Washington and Oregon and observed that about 13 percent of the
observed collision mortalities were nonnative upland game birds: Ring-
necked pheasant, gray partridge (Perdix perdix), and chukar (Alectoris
chukar). Although the risk of collision with individual wind turbines
appears low, commercial wind energy developments can directly alter
existing habitat, contribute to habitat and population fragmentation,
and cause more subtle alterations that influence how species use
habitats in proximity to these developments (National Research Council
2007, pp. 72-84).
Electrical transmission lines can directly affect prairie grouse by
posing a collision hazard (Leopold 1933, p. 353; Connelly et al. 2000,
p. 974; Patten et al. 2005b, pp. 240, 242) and can indirectly lead to
decreased lek recruitment, increased predation, and facilitate invasion
by nonnative plants. The physical footprint of the actual project is
typically much smaller than the actual impact of the transmission line
itself. Lesser prairie-chickens exhibit strong avoidance of tall
vertical features such as utility transmission lines (Pitman et al.
2005, pp. 1267-1268). In typical lesser prairie-chicken habitat where
vegetation is low and the terrain is relatively flat, power lines and
power poles provide attractive hunting, loafing, and roosting perches
for many species of raptors (Steenhof et al. 1993, p. 27). The elevated
advantage of transmission lines and power poles serve to increase a
raptor's range of vision, allow for greater speed during attacks on
prey, and serve as territorial markers. Raptors actively seek out power
lines and poles in extensive grassland areas where natural perches are
limited. While the effect of this predation on lesser prairie-chickens
undoubtedly depends on raptor densities, as the number of perches or
nesting features increase, the impact of avian predation will increase.
Additional discussion concerning the influence of vertical structures
on predation of lesser prairie-chickens can be found in the ``Causes of
Habitat Fragmentation Within Lesser Prairie-Chicken Range'' section
above, and additional information on predation is provided in a
separate discussion under ``Predation'' below.
Transmission lines, particularly due to their length, can be a
significant barrier to dispersal of prairie grouse, disrupting
movements to feeding, breeding, and roosting areas. Both lesser and
greater prairie-chickens avoided otherwise suitable habitat near
transmission lines and crossed these power lines much less often than
nearby roads, suggesting that power lines are a particularly strong
barrier to movement (Pruett et al. 2009a, pp. 1255-1257). Because
lesser prairie-chickens avoid tall vertical structures like
transmission lines and because transmission lines can increase
predation rates, leks located in the vicinity of these structures may
see reduced recruitment of new males to the
[[Page 73872]]
lek (Braun et al. 2002, pp. 339-340, 343-344). Lacking recruitment,
leks may disappear as the number of older males decline due to death or
emigration. Linear corridors such as road networks, pipelines, and
transmission line rights-of-way can create soil conditions conducive to
the spread of invasive plant species, at least in semiarid sagebrush
habitats (Knick et al. 2003, p. 619; Gelbard and Belnap 2003, pp. 424-
425), but the scope of this impact within the range of the lesser
prairie-chicken is unknown. Spread of invasive plants is most critical
where established populations of invasive plants begin invading areas
of native grassland vegetation.
Electromagnetic fields associated with transmission lines alter the
behavior, physiology, endocrine systems, and immune function in birds,
with negative consequences on reproduction and development (Fernie and
Reynolds 2005, p. 135). Birds are diverse in their sensitivities to
electromagnetic field exposure with domestic chickens known to be very
sensitive. Although many raptor species are less affected by these
fields (Fernie and Reynolds 2005, p. 135), no specific studies have
been conducted on lesser prairie-chickens. However electromagnetic
fields associated with powerlines and telecommunication towers may
explain, at least in part, avoidance of such structures by sage grouse
(Wisdom et al. 2011, pp. 467-468).
Identification of the actual number of proposed wind energy
projects that will be built in any future timeframe is difficult to
accurately discern. An analysis of the Federal Aviation
Administration's obstacle database provides some insight into the
number of existing and proposed wind generation towers. The Federal
Aviation Administration is responsible for ensuring wind towers and
other vertical structures are constructed in a manner that ensures the
safety and efficient use of the navigable airspace. In accomplishing
this mission, they evaluate applications submitted by the party
responsible for the proposed construction and alteration of these
structures. Included in the application is information on the precise
location of the proposed structure. This information can be used, in
conjunction with other databases, to determine the number of existing
and proposed wind generation towers within the historical and occupied
range of the lesser prairie-chicken. Analysis of this information, as
available in April 2010, reveals that 6,279 constructed towers are
within the historical range of the lesser prairie-chicken. Some 8,501
towers have been approved for construction, and another 1,693 towers
were pending approval within the historical range of the lesser
prairie-chicken. While not all of these structures are wind generation
towers, the vast majority are. Other structures included within the
database are radio, meteorological, telecommunication, and similar
types of towers.
A similar analysis was conducted on lesser prairie-chicken occupied
range. As of April 2010, the occupied range included 173 towers. Some
1,950 towers had been approved for construction, and another 250 towers
were awaiting approval. In January of 2012, the Federal Aviation
Administration's obstacle database showed that there are some 405
existing wind turbines in or within 1.6 km (1 mi) of the estimated
occupied range. In March of 2012, there were 4,887 wind turbines
awaiting construction, based on this database. Additionally, the
Southwest Power Pool provides public access to its Generation
Interconnection Queue (https://studies.spp.org/GenInterHomePage.cfm),
which provides all of the active requests for connection from new
energy generation sources requiring Southwest Power Pool approval prior
to connecting with the transmission grid. The Southwest Power Pool is a
regional transmission organization which overlaps all or portions of
nine States and functions to ensure reliable supplies of power,
adequate transmission infrastructure, and competitive wholesale prices
of electricity exist. In 2010, within the Southwest Power Pool portion
of Kansas, New Mexico, Oklahoma, and Texas, there were 177 wind
generation interconnection study requests totaling 31,883 MW awaiting
approval. A maximum development scenario, assuming all of these
projects are built and they install all 2.3 MW wind turbines, would
result in approximately 13,862 wind turbines being erected in these
four States.
The possible scope of this anticipated wind energy development on
the status of the lesser prairie-chicken can readily be seen in
Oklahoma where the locations of many of the current and historically
occupied leks are known. Most remaining large tracts of untilled native
rangeland, and hence lesser prairie-chicken habitat, occur on
topographic ridges. Leks, the traditional mating grounds of prairie
grouse, are consistently located on elevated grassland sites with few
vertical obstructions (Flock 2002, p. 35). Because of the increased
elevation, these ridges also are prime sites for wind turbine
development. In cooperation with ODWC, Service personnel in 2005
quantified the potential degree of wind energy development in relation
to existing populations of lesser prairie-chicken in Oklahoma. Using
ArcView mapping software, all active and historical lesser prairie-
chicken lek locations in Oklahoma, as of the mid 1990s (n = 96), and
the current occupied range, were compared with the Oklahoma Neural Net
Wind Power Development Potential Model map created by the Oklahoma Wind
Power Assessment project. The mapping analysis revealed that 35 percent
of the recently occupied range in Oklahoma is within areas designated
by the Oklahoma Wind Power Assessment as ``excellent'' for wind energy
development. When both the ``excellent'' and ``good'' wind energy
development classes are combined, some 55 percent of the lesser
prairie-chicken's occupied range in Oklahoma lies within those two
classes.
When leks were examined, the same analysis revealed a nearly
complete overlap on all known active and historical lek locations,
based on the known active leks during the mid 1990s. Roughly 91 percent
of the known lesser prairie-chicken lek sites in Oklahoma are within 8
km (5 mi) of land classified as ``excellent'' for wind development
(O'Meilia 2005). Over half (53 percent) of all known lek sites in
Oklahoma occur within 1.6 km (1 mi) of lands classified as
``excellent'' for commercial wind energy development. This second
metric is particularly relevant given the average home range for a
lesser prairie-chicken is about 10 sq km (4 sq mi) and that a majority
of lesser prairie-chicken nesting generally occurs, on average, within
3.4 km (2.1 mi) of active leks (Hagen and Giesen 2005, p. 2). Using
Robel's (2002) estimate derived for the greater prairie-chicken of the
zone of avoidance for a single commercial-scale wind turbine (1.6 km or
1 mi), development of commercial wind farms likely will have a
significant adverse influence on reproduction of the lesser prairie-
chicken, provided lesser prairie-chickens avoid nesting within 1.6 km
(1 mi) of each turbine.
Unfortunately, similar analyses are not available for the other
States due to a lack of comparable information on the location of lek
sites. Considering western Kansas currently supports the largest number
and distribution of lesser prairie-chickens of all five States, the
influence of wind energy development on the lesser prairie-chicken in
Kansas would likely be just as significant. In 2006, the Governor of
Kansas initiated the Governor's 2015 Renewable Energy Challenge, an
objective of which is to have 1,000 MW of renewable energy
[[Page 73873]]
capacity in Kansas by 2015 (Cita et al. 2008, p. 1). A cost-benefit
study (Cita et al. 2008, Appendix B) found that wind power was the most
likely and most cost effective form of renewable energy resource for
Kansas. Modestly assuming an average of 2 MW per turbine--most
commercial scale turbines are between 1.5 and 2.5 MW--some 500 turbines
would be erected in Kansas if this goal is to be met.
While not all of those turbines would be placed in occupied
habitat, and some overlap in avoidance would occur if turbines were
oriented in a typical wind farm array, the potential impact could be
significant. First, the best wind potential in Kansas occurs in the
western two-thirds of the State and largely overlaps the currently
occupied lesser prairie-chicken range (DOE, National Renewable energy
Laboratory 2010b, p. 1). Additionally, Kansas has a voluntary
moratorium on the development of wind power in the Flint Hills of
eastern Kansas, which likely will shift the focus of development into
the central and western portions of the State. Taking these two factors
into consideration, construction of much of the new wind power
anticipated in the Governor's 2015 Renewable Energy Challenge likely
would occur in the western two-thirds of Kansas. If we assume that even
one-half of the estimated 500 turbines are placed in lesser prairie-
chicken range, 250 turbines would individually impact over 101,000 ha
(250,000 ac), based on an avoidance distance of 1.6 km (1 mi). The
habitat loss resulting from the above scenario would further reduce the
extent of large, unfragmented parcels and influence connectivity
between remaining occupied blocks of habitat, reducing the amount of
suitable habitat available to the lesser prairie-chicken. Consequently,
siting of wind energy arrays and associated facilities, including
electrical transmission lines, appears to be a serious threat to lesser
prairie-chickens in western Kansas within the near future (Rodgers
2007a).
In Colorado, the DOE, National Renewable Energy Laboratory (2010b,
p. 1) rated the southeastern corner of Colorado as having good wind
resources, the largest area of Colorado with that ranking. The area
almost completely overlaps the currently occupied range of the lesser
prairie-chicken in Colorado. The CPW reported that commercial wind
development is occurring in Colorado, but that most of the effort is
currently centered north of the occupied range of lesser prairie-
chicken in southeastern Colorado.
Wind energy development in New Mexico is a lower priority than in
other States within the range of the lesser prairie-chicken. In New
Mexico, the suitability for wind energy development in the currently
occupied range of the lesser prairie-chicken is only rated as fair
(DOE, National Renewable Energy Laboratory 2010b, p. 1). However, some
parts of northeastern New Mexico within lesser prairie-chicken
historical range have been rated as excellent. Northeastern New Mexico
is important to lesser prairie-chicken conservation because this area
is vital to efforts to reestablish or reconnect the New Mexico lesser
prairie-chicken population to those in Colorado and the Texas
panhandle.
In Texas, the Public Utility Commission recently directed the
Electric Reliability Council of Texas (ERCOT) to develop transmission
plans for wind capacity to accommodate between 10,000 and 25,000 MW of
power (American Wind Energy Association 2007b, pp. 2-3). ERCOT is a
regional transmission organization with jurisdiction over most of
Texas. The remainder of Texas, largely the Texas panhandle, lies within
the jurisdiction of the Southwest Power Pool. A recent assessment from
ERCOT identified more than 130,000 MW of high-quality wind sites in
Texas, more electricity than the entire State currently uses. The
establishment of Competitive Renewable Energy Zones by ERCOT within the
State of Texas will facilitate wind energy development throughout
western Texas. The top four Competitive Renewable Energy Zones, based
on the development priority of each zones are located within occupied
and historical lesser prairie-chicken habitat in the Texas panhandle.
There is a high level of overlap between lesser prairie-chicken
currently occupied range in Texas and the Competitive Renewable Energy
Zones, which are designated for future wind energy development in the
Texas panhandle.
Wind energy and associated transmission line development in the
Texas panhandle and portions of west Texas represent a threat to extant
lesser prairie-chicken populations in the State. Once established, wind
farms and associated transmission features would severely hamper future
efforts to restore population connectivity and gene flow (transfer of
genetic information from one population to another) between existing
populations that are currently separated by incompatible land uses in
the Texas panhandle.
Development of high-capacity transmission lines is critical to the
development of the anticipated wind energy resources in ensuring that
the generated power can be delivered to the consumer. According to
ERCOT (American Wind Energy Association 2007a, p. 9), every $1 billion
invested in new transmission capacity enables the construction of $6
billion of new wind farms. We estimate, based on a spatial analysis
prepared by The Nature Conservancy under their license agreement with
Ventyx Energy Corporation, that there are some 35,220 km (21,885 mi) of
transmission lines, having a capacity of 69 kilovolts (kV) or larger,
in service within the historical range of the lesser prairie-chicken.
Within the estimated currently occupied range, this analysis estimated
that about 3,610 km (2,243 mi) of transmission lines with a capacity of
69kV and larger are currently in service. Within the currently occupied
range, this same analysis revealed that an additional 856 km (532 mi)
of 69kV or higher transmission line is anticipated to be in service
within the near future.
The Southwest Power Pool has information about several proposed
electric transmission line upgrades. This organization identified
approximately 423 km (263 mi) of proposed new transmission lines,
commonly referred to as the ``X Plan'', that were being evaluated
during the transmission planning process. Transmission planning
continues to move forward, and numerous alternatives are being
evaluated, many of which will connect transmission capacity throughout
all or portions of occupied lesser prairie-chicken range and serve to
catalyze extensive wind energy development throughout much of the
remaining occupied lesser prairie-chicken range in Kansas, Oklahoma,
and Texas. Additionally, Clean Line Energy is planning to build a major
direct current transmission line that would originate within the
western portion of the Oklahoma panhandle, travel the length of the
panhandle region, and then drop south to near Woodward, Oklahoma,
before continuing eastward across Oklahoma and Arkansas.
A similar direct current transmission line, known as the Grain Belt
Express, is planned for Kansas. The line would originate in west-
central Kansas and continue to its endpoint in the upper Midwestern
United States. Very little opportunity to interconnect with these lines
exists due to the anticipated high cost associated with development of
an appropriate interconnecting substation. Consequently, most of the
anticipated wind power that will be transmitted across the Oklahoma and
Kansas projects likely will occur near the western terminals associated
with these two lines. Assuming a fairly realistic build-out scenario
for these
[[Page 73874]]
transmission lines, in which wind power projects would most likely be
constructed within 170 km (105 mi) of the western end points of each
line, would place most of the estimated occupied range in Colorado,
Kansas, Oklahoma, and northeast Texas within the anticipated
development zone. Although both of these projects are still relatively
early in the planning process, and the specific environmental impacts
have yet to be determined, a reasonably likely wind power development
scenario would place much of the occupied range at risk of development.
In summary, wind energy and associated infrastructure development
is occurring now and is expected to continue into the foreseeable
future within occupied portions of lesser prairie-chicken habitat.
Proposed transmission line improvements will serve to facilitate
further development of additional wind energy resources. Future wind
energy developments, based on the known locations of areas with
excellent to good wind energy development potential, likely will have
substantial overlap with known lesser prairie-chicken populations.
There is little published information on the specific effects of wind
power development on lesser prairie-chickens. Most published reports on
the effects of wind power development on birds focus on the risks of
collision with towers or turbine blades. However, we do not expect that
significant numbers of collisions with spinning blades would be likely
to occur due to avoidance of the wind towers and associated
transmission lines by lesser prairie-chickens. The most significant
impact of wind energy development on lesser prairie-chickens is caused
by the presence of vertical structures (turbine towers and transmission
lines) within suitable habitat. Avoidance of these vertical structures
by lesser prairie-chickens can be as much as 1.6 km (1 mi), resulting
in large areas (814 ha (2,011 ac) for a single turbine) of unsuitable
habitat relative to the overall footprint of a single turbine. Where
such development has occurred or is likely to occur, these areas are no
longer suitable for lesser prairie-chicken even though many of the
typical habitat components used by lesser prairie-chicken remain.
Therefore, considering the scale of current and future wind development
that is likely within the range of the lesser prairie-chicken and the
significant avoidance response of the species to these developments, we
conclude that wind energy development is a threat to the species,
especially when considered in combination with other habitat
fragmenting activities.
Roads and Other Similar Linear Features
Similar to transmission lines, roads are a linear feature on the
landscape that can contribute to loss and fragmentation of suitable
habitat, and can fragment populations as a result of behavioral
avoidance. The observed behavioral avoidance associated with roads is
likely due to noise, visual disturbance, and increased predator
movements paralleling roads. For example, roads are known to contribute
to lek abandonment when they disrupt the important habitat features
associated with lek sites (Crawford and Bolen 1976b, p. 239). The
presence of roads allows human encroachment into habitats used by
lesser prairie-chickens, further causing fragmentation of suitable
habitat patches. Some mammalian species known to prey on lesser
prairie-chickens, such as red fox, raccoons, and striped skunks, have
greatly increased their distribution by dispersing along roads (Forman
and Alexander 1998, p. 212; Forman 2000, p. 33; Frey and Conover 2006,
pp. 1114-1115).
Traffic noise from roads may indirectly impact lesser prairie-
chickens. Because lesser prairie-chickens depend on acoustical signals
to attract females to leks, noise from roads, oil and gas development,
wind turbines, and similar human activity may interfere with mating
displays, influencing female attendance at lek sites and causing young
males not to be drawn to the leks. Within a relatively short period,
leks can become inactive due to a lack of recruitment of new males to
the display grounds.
Roads also may influence lesser prairie-chicken dispersal, likely
dependent upon the volume of traffic, and thus disturbance, associated
with the road. However, roads likely do not constitute a significant
barrier to dispersal. Lesser prairie-chickens have been shown to avoid
areas of suitable habitat near larger, multiple-lane, paved roads
(Pruett et al. 2009a, pp. 1256, 1258). Generally, roads were between
4.1 and 5.3 times less likely to occur in areas used by lesser prairie-
chickens than areas that were not used and can influence habitat and
nest site selection (Hagen et al. 2011, pp. 68, 71-72). Lesser prairie-
chickens are thought to avoid major roads due to disturbance caused by
traffic volume and, perhaps behaviorally, to avoid exposure to
predators that may use roads as travel corridors. Similar behavior has
been documented in sage grouse (Oyler-McCance et al. 2001, p. 330).
When factors believed to have contributed to extirpation of sage grouse
were examined, Wisdom et al. (2011, p. 467) found that extirpated range
contained almost 27 times the human density, was 60 percent closer to
highways, and had 25 percent higher density of roads, in contrast to
occupied range.
Roads also can cause direct mortality due to collisions with
automobiles and possibly increased predation. Although individual
mortality resulting from collisions with moving vehicles does occur,
the mortalities typically are not monitored or recorded. Therefore we
cannot determine the importance of direct mortality from roads on
lesser prairie-chicken populations.
Using the data layers provided in StreetMap USA, a product of ESRI
Corporation and intended for use with ArcGIS, we can estimate the scope
of the impact of roads on lesser prairie-chickens. Within the entire
historical range, there are 622,061 km (386,581 mi) of roads. This
figure includes major Federal and state highways as well as county
highways and smaller roads. Within the currently occupied range, some
81,874 km (50,874 mi) of roads have been constructed. While we don't
anticipate significant expansion of the number of existing roads, these
roads have already contributed to significant habitat fragmentation
within the historical and occupied range of the lesser prairie-chicken.
This fragmentation in combination with other causes described in this
document further reduces the habitat available to support lesser
prairie-chicken populations. The resultant fragmentation is detrimental
to lesser prairie-chickens because they rely on large, expansive areas
of contiguous rangeland and grassland to complete their life cycle.
In summary, roads occur throughout the range of the lesser prairie-
chicken and contribute to the threat of cumulative habitat
fragmentation to the species.
Petroleum Production
Petroleum production, primarily oil and gas development, is
occurring over much of the historical and current range of the lesser
prairie-chicken. Oil and gas development involves activities such as
surface exploration, exploratory drilling, field development, and
facility construction. Ancillary facilities can include compressor
stations, pumping stations, and electrical generators. Activities such
as well pad construction, seismic surveys, access road development,
power line construction, and pipeline corridors can directly impact
lesser prairie-chicken
[[Page 73875]]
habitat. Indirect impacts from noise, gaseous emissions, and human
presence also influence habitat quality in oil and gas development
areas. These activities affect lesser prairie-chickens by disrupting
reproductive behavior (Hunt and Best 2004, p. 41) and through habitat
fragmentation and conversion (Hunt and Best 2004, p. 92). Smith et al.
(1998, p. 3) observed that almost one-half, 13 of 29, of the abandoned
leks examined in southeastern New Mexico in an area of intensive oil
and gas development had a moderate to high level of noise. Hunt and
Best (2004, p. 92) found that abandoned leks in southeastern New Mexico
had more active wells, more total wells, and greater length of access
road than active leks. They concluded that petroleum development at
intensive levels, with large numbers of wells in close proximity to
each other necessitating large road networks and an increase in the
number of power lines, is likely not compatible with life-history
requirements of lesser prairie-chickens (Hunt and Best 2004, p. 92).
Impacts from oil and gas development and exploration is the primary
reason thought to be responsible for the species' near absence
throughout previously occupied portions of the Carlsbad BLM unit in
southeastern New Mexico (Belinda 2003, p. 3). This is supported by
research examining lesser prairie-chicken losses over the past 20 years
on Carlsbad BLM lands (Hunt and Best 2004, pp. 114-115). In this study,
factor analysis (a statistical method used to describe variability
among observed variables in reference to a number of unobserved
variables) of characters associated with active and abandoned leks was
conducted to determine which potential causes were associated with the
population decline. Those variables associated with oil and gas
development explained 32 percent of observed lek abandonment (Hunt and
Best 2004) and the consequent population extirpation.
Although the Service presently lacks the information to
specifically quantify and analyze drilling activity throughout the
entire historical and occupied range of the lesser prairie-chicken,
known activity within certain areas of the historical range
demonstrates the significance of the threat. For example, the amount of
habitat fragmentation due to oil and gas extraction in the Texas
panhandle and western Oklahoma associated with the Buffalo Wallow oil
and gas field within the Granite Wash formation of the Anadarko Basin
has steadily increased over time. In 1982, the rules for the Buffalo
Wallow field allowed one well per 130 ha (320 ac). In late 2004, the
Texas Railroad Commission changed the field rule regulations for the
Buffalo Wallow oil and gas field to allow oil and gas well spacing to a
maximum density of one well per 8 ha (20 ac) (Rothkopf et al. 2011, p.
1). When fully developed at this density, the region will have
experienced a 16-fold increase in habitat fragmentation in comparison
with the rates allowed prior to 2004.
In the BLM's Special Status Species Record of Decision and approved
Resource Management Plan Amendment (RMPA), some limited protections for
the lesser prairie-chicken in New Mexico are provided by reducing the
number of drilling locations, decreasing the size of well pads,
reducing the number and length of roads, reducing the number of
powerlines and pipelines, and implementing best management practices
for development and reclamation (BLM 2008, pp. 5-31). The RMPA provides
guidance for management of approximately 344,000 ha (850,000 ac) of
public land and 121,000 ha (300,000 ac) of Federal minerals in Chaves,
Eddy, Lea, and Roosevelt Counties in New Mexico. Implementation of
these restrictions, particularly curtailment of new mineral leases,
would be concentrated in the Core Management and Primary Population
Areas (BLM 2008, pp. 9-11). The Core Management and Primary Population
Areas are located in the core of the lesser prairie-chicken occupied
range in New Mexico. The effect of these best management practices on
the status of the lesser prairie-chicken is unknown, particularly
considering about 60,000 ha (149,000 ac) have already been leased in
those areas (BLM 2008, p. 8). The plan stipulates that measures
designed to protect the lesser prairie-chicken and dunes sagebrush
lizard may not allow approval of all spacing unit locations or full
development of the lease (BLM 2008, p. 8).
Oil and gas development and exploration is ongoing in the remaining
States although the precise extent is currently unknown. Some
development is anticipated in Baca County, Colorado, although the
timeframe for initiation of those activities is uncertain (CPW 2007, p.
2). In Oklahoma, oil and gas exploration statewide continues at a high
level. Since 2002, the average number of active drilling rigs in
Oklahoma has steadily risen (Boyd 2009, p. 1). Since 2004, the number
of active drilling rigs has remained above 150, reflecting the highest
level of sustained activity since the `boom' years from the late 1970s
through the mid-1980s in Oklahoma (Boyd 2007, p. 1).
Wastewater pits associated with energy development are not
anticipated to be a major threat to lesser prairie-chickens primarily
due to the presence of infrastructure and the lack of suitable cover
near these pits. In formations with high levels of hydrogen sulfide
gas, the presence of this gas can cause mortality.
In summary, infrastructure associated with current petroleum
production contributes to the current threat of habitat fragmentation
to the lesser prairie-chicken. Reliable information about future trends
for petroleum production is not known for the entire range of the
species; however, information for portions of Oklahoma, New Mexico, and
Texas indicate petroleum production is a significant threat to the
species into the foreseeable future.
Predation
Lesser prairie-chickens have coevolved with a variety of predators,
but none are lesser prairie-chicken specialists. Prairie falcon (Falco
mexicanus), northern harrier (Circus cyaneus), Cooper's hawk (Accipiter
cooperii), great-horned owl (Bubo virginianus), other unspecified birds
of prey (raptors), and coyote (Canis latrans) have been identified as
predators of lesser prairie-chicken adults and chicks (Davis et al.
1979, pp. 84-85; Merchant 1982, p. 49; Haukos and Broda 1989, pp. 182-
183; Giesen 1994a, p. 96). Predators of nests and eggs also include
Chihuahuan raven (Corvus cryptoleucus), striped skunk (Mephitis
mephitis), ground squirrels (Spermophilus spp.), and bullsnakes
(Pituophis melanoleucus), as well as coyotes and badgers (Taxidea
taxus) (Davis et al. 1979, p. 51; Haukos 1988, p. 9; Giesen 1998, p.
8).
Lesser prairie-chicken predation varies in both form and frequency
throughout the year. In Kansas, Hagen et al. (2007, p. 522) attributed
some 59 percent of the observed mortality of female lesser prairie-
chickens to mammalian predators and between 11 and 15 percent,
depending on season, to raptors. Coyotes were reported to be
responsible for some 64 percent of the nest depredations observed in
Kansas (Pitman et al. 2006a, p. 27). Observed mortality of male and
female lesser prairie-chickens associated with raptor predation reached
53 percent in Oklahoma and 56 percent in New Mexico (Wolfe et al. 2007,
p. 100). Predation by mammals was reported to be 47 percent in Oklahoma
and 44 percent in New Mexico (Wolfe et al. 2007, p. 100). In Texas,
over the course of three nonbreeding seasons, Boal and Pirius (2012, p.
8) assessed cause-
[[Page 73876]]
specific mortality for 13 lesser prairie-chickens. Avian predation was
identified as the cause of death in 10 of those individuals, and
mammalian predation was responsible for 2 deaths. The cause of death
could not be identified in one of those individuals. Behney et al.
(2012, p. 294) suspected that mammalian and reptilian predators had a
greater influence on lesser prairie-chicken mortality during the
breeding season than raptors.
Predation is a naturally occurring phenomenon and generally does
not pose a risk to wildlife populations unless the populations are
extremely small or have an abnormal level of vulnerability to
predation. The lesser prairie-chicken's cryptic plumage and behavioral
adaptations allow the species to persist under normal predation
pressures. Birds may be most susceptible to predation while on the lek
when birds are more conspicuous. Both Patten et al. (2005b, p. 240) and
Wolfe et al. (2007, p. 100) reported that raptor predation increased
coincident with lek attendance. Patten et al. (2005b, p. 240) stated
that male lesser prairie-chickens are more vulnerable to predation when
exposed during lek displays than they are at other times of the year
and that male lesser prairie-chicken mortality was chiefly associated
with predation. However, during 650 hours of lek observations in Texas,
raptor predation at leks was considered to be uncommon and an unlikely
factor responsible for declines in lesser prairie-chicken populations
(Behney et al. 2011, pp. 336-337). But Behney et al. (2012, p. 294)
observed that the timing of lekking activities in their study area
corresponded with the lowest observed densities of raptors and that
lesser prairie-chickens contend with a more abundant and diverse
assemblage of raptors in other seasons.
Predation and related disturbance of mating activities by predators
may impact reproduction in lesser prairie-chickens. For females,
predation during the nesting season likely would have the most
significant impact on lesser prairie-chicken populations, particularly
if that predation resulted in total loss of a particular brood.
Predation on lesser prairie-chicken may be especially significant
relative to nest success. Nest success and brood survival of greater
prairie-chickens accounted for most of the variation in population
finite rate of increase (Wisdom and Mills 1997, p. 308). Bergerud
(1988, pp. 646, 681, 685) concluded that population changes in many
grouse species are driven by changes in breeding success. An analysis
of Attwater's prairie-chicken supported this conclusion (Peterson and
Silvy 1994, p. 227). Recent demographic research on lesser prairie-
chicken in southwestern Kansas confirmed that changes in nest success
and chick survival, two factors closely associated with vegetation
structure, have the largest impact on population growth rates and
viability (Hagen et al. 2009, p. 1329).
Rates of predation on lesser prairie-chicken likely are influenced
by certain aspects of habitat quality such as fragmentation or other
forms of habitat degradation (Robb and Schroeder 2005, p. 36). As
habitat fragmentation increases, suitable habitats become more
spatially restricted and the effects of terrestrial nest predators on
grouse populations may increase (Braun et al. 1978, p. 316). Nest
predators typically have a positive response (e.g., increased
abundance, increased activity, and increased species richness) to
fragmentation, although the effects are expressed primarily at the
landscape scale (Stephens et al. 2003, p. 4). Similarly, as habitat
quality decreases through reduction in vegetative cover due to grazing
or herbicide application, predation of lesser prairie-chicken nests,
juveniles, and adults are all expected to increase. For this reason,
ensuring adequate shrub cover and removing raptor perches such as
trees, power poles, and fence posts may lower predation more than any
conventional predator removal methods (Wolfe et al. 2007, p. 101). As
discussed at several locations within this document, existing and
foreseeable development of transmission lines, fences, and vertical
structures will either contribute to additional predation on lesser
prairie-chickens or cause areas of suitable habitat to be abandoned due
to behavior avoidance by lesser prairie-chickens. Increases in the
encroachment of trees into the native prairies also will contribute to
increased incidence of predation by providing additional perches for
avian predators. Because predation has a strong relationship with
certain anthropogenic factors, such as fragmentation, vertical
structures, and roads, continued development is likely to increase the
effects of predation on lesser prairie-chickens beyond natural levels.
As a result, predation is likely to contribute to the declining status
of the species.
Disease
Giesen (1998, p. 10) provided no information on ectoparasites or
infectious diseases in lesser prairie-chicken, although several
endoparasites, including nematodes and cestodes, are known to infect
the species. In Oklahoma, Emerson (1951, p. 195) documented the
presence of the external parasites (biting lice-Order Mallophaga)
Goniodes cupido and Lagopoecus sp. in an undisclosed number of lesser
prairie-chickens. Between 1997 and 1999, Robel et al. (2003, p. 342)
conducted a study of helminth parasites in lesser prairie-chicken from
southwestern Kansas. Of the carcasses examined, 95 percent had eye worm
(Oxyspirura petrowi), 92 percent had stomach worm (Tetrameres sp.), and
59 percent had cecal worm (Subulura sp.) (Robel et al. 2003, p. 341).
No adverse impacts to the lesser prairie-chicken population they
studied were evident as a result of the observed parasite burden.
Addison and Anderson (1969, p. 1223) also found eyeworm (O. petrowi)
from a limited sample of lesser prairie-chickens in Oklahoma. The
eyeworm also has been reported from lesser prairie-chickens in Texas
(Pence and Sell 1979, p. 145). Pence and Sell (1979, p. 145) also
observed the roundworm Heterakis isolonche and the tapeworm Rhabdometra
odiosa from lesser prairie-chickens in Texas. Smith et al. (2003, p.
347) reported on the occurrence of blood and fecal parasites in lesser
prairie-chickens in eastern New Mexico. Eight percent of the examined
birds were infected with Eimeria tympanuchi, an intestinal parasite,
and 13 percent were infected with Plasmodium pedioecetii, a hematozoan.
Stabler (1978, p. 1126) first reported Plasmodium pedioecetii in the
lesser prairie-chicken from samples collected from New Mexico and
Texas. In the spring of 1997, a sample of 12 lesser prairie-chickens
from Hemphill County, Texas, were tested for the presence of disease
and parasites. No evidence of viral or bacterial diseases,
hemoparasites, parasitic helminths, or ectoparasites was found (Hughes
1997, p. 2).
Peterson et al. (2002, p. 835) reported on an examination of 24
lesser prairie-chickens from Hemphill County, Texas, for several
disease agents. Lesser prairie-chickens were seropositive for both the
Massachusetts and Arkansas serotypes of avian infectious bronchitis, a
type of coronavirus. All other tests were negative.
Reticuloendotheliosis is a viral disease documented from poultry,
which has been found to cause serious mortality in captive Attwater's
prairie-chickens and greater prairie-chickens. Researchers surveyed
blood samples from 184 lesser prairie-chickens from three States during
1999 and 2000, for the presence of reticuloendotheliosis. All samples
were negative, suggesting that reticuloendotheliosis may not be a
[[Page 73877]]
serious problem for most wild populations of lesser prairie-chicken
(Wiedenfeld et al. 2002, p. 143).
The impact of West Nile virus on lesser prairie-chickens is
unknown. Recently scientists at Texas Tech University detected West
Nile virus in a small percentage (1.3 percent) of the lesser prairie-
chicken blood samples they analyzed. Other grouse, such as ruffed
grouse (Bonasa umbellus), have been documented to harbor West Nile
virus infection rates similar to some corvids (crows, jays, and
ravens). For 130 ruffed grouse tested in 2000, all distant from known
West Nile virus epicenters, 21 percent tested positive. This was
remarkably similar to American crows (Corvus brachyrhynchos) and blue
jays (Cyanocitta cristata) (23 percent for each species), species with
known susceptibility to West Nile virus (Bernard et al. 2001, p. 681).
Recent analysis of the degree of threat to prairie grouse from
parasites and infectious disease concluded that microparasitic
infections that cause high mortality across a broad range of galliform
(wildfowl species such as turkeys, grouse, and chickens) hosts have the
potential to extirpate small, isolated prairie grouse populations
(Peterson 2004, p. 35).
Nonparasitic diseases caused by mycotoxins, as well as pesticides
and other toxic compounds, also have the potential to influence
population dynamics. However, the incidence of disease or parasite
infestations in regulating populations of the lesser prairie-chicken is
unknown. The Lesser Prairie-Chicken Interstate Working Group (Mote et
al. 1999, p. 12) concluded that, while density-dependent transmission
of disease was unlikely to have a significant effect on lesser prairie-
chicken populations, a disease that was transmitted independently of
density could have drastic effects. Further research is needed to
establish whether parasites regulate prairie grouse populations.
Peterson (2004, p. 35) urged natural resource decisionmakers to be
aware that macro- and micro-parasites cannot be safely ignored as
populations of species such as the lesser prairie-chicken become
smaller, more fragmented, and increasingly vulnerable to the effects of
disease. Some degree of impact of parasites and disease is a naturally
occurring phenomenon for most species and one element of compensatory
mortality that occurs among many species. There is no information that
indicates parasites or disease are causing, or contributing to, the
decline of any lesser prairie-chicken populations, and, at this time,
we have no basis for concluding that disease or parasite loads are a
threat to any lesser prairie-chicken populations. Consequently, we do
not consider disease or parasite infections to be a significant factor
in the decline of the lesser prairie-chicken. However, if populations
continue to decline or become more fragmented, even small changes in
habitat abundance or quality could have more significant consequences.
Hunting and Other Forms of Recreational, Educational, or Scientific Use
In the late 19th century, lesser prairie-chickens were subject to
market hunting (Jackson and DeArment 1963, p. 733; Fleharty 1995, pp.
38-45; Jensen et al. 2000, p. 170). Harvest has been regulated since
approximately the turn of the 20th century (Crawford 1980, pp. 3-4).
Currently, the lesser prairie-chicken is classified as a game species
in Kansas, New Mexico, Oklahoma, and Texas, although authorized harvest
is allowed only in Kansas. In March of 2009, Texas adopted a temporary,
indefinite suspension of their current 2-day season until lesser
prairie-chicken populations recover to huntable levels. Previously in
Texas, lesser prairie-chicken harvest was not allowed except on
properties with an approved wildlife management plan specifically
addressing the lesser prairie-chicken. When both Kansas and Texas
allowed lesser prairie-chicken harvest, the total annual harvest for
both States was fewer than 1,000 birds annually.
In Kansas, the current bag limit is one bird daily for lesser
prairie-chickens located south of Interstate 70 and two birds for
lesser prairie-chickens located north of Interstate 70. The season
typically begins in early November and runs through the end of December
in southwestern Kansas. In the northwestern portion of the State, the
season typically extends through the end of January. During the 2006
season, hunters in Kansas expended 2,020 hunter-days and harvested
approximately 340 lesser prairie-chickens. In 2010, 2,863 hunter-days
were expended and an estimated 633 lesser prairie-chickens were
harvested in Kansas (Pitman 2012a). Given the low number of lesser
prairie-chickens harvested per year in Kansas relative to the
population size, the statewide harvest is probably insignificant at the
population level. There are no recent records of unauthorized harvest
of lesser prairie-chickens in Kansas (Pitman 2012b).
Two primary hypotheses exist regarding the influence of hunting on
harvested populations--hunting mortality is either additive to other
sources of mortality or nonhunting mortality compensates for hunting
mortality, up to some threshold level. The compensatory hypothesis
essentially implies that harvest by hunting removes only surplus
individuals, and individuals that escape hunting mortality will have a
higher survival rate until the next reproductive season. Both Hunt and
Best (2004, p. 93) and Giesen (1998, p. 11) do not believe hunting has
an additive mortality on lesser prairie-chickens, although, in the
past, hunting during periods of low population cycles may have
accelerated declines (Taylor and Guthery 1980b, p. 2). However, because
most remaining lesser prairie-chicken populations are now very small
and isolated, and because they naturally exhibit a clumped distribution
on the landscape, they are likely vulnerable to local extirpations
through many mechanisms, including harvest by humans. Braun et al.
(1994, p. 435) called for definitive experiments that evaluate the
extent to which hunting is additive at different harvest rates and in
different patch sizes. They suggested conservative harvest regimes for
small or fragmented grouse populations because fragmentation likely
decreases the resilience of populations to harvest. Sufficient
information to determine the rate of localized harvest pressure is
unavailable and, therefore, the Service cannot determine whether such
harvest contributes to local population declines. We do not consider
hunting to be a threat to the species at this time. However, as
populations become smaller and more isolated by habitat fragmentation,
their resiliency to the influence of hunting pressure will decline,
likely increasing the degree of threat that hunting may pose to the
species.
An additional activity that has the potential to negatively affect
individual breeding aggregations of lesser prairie-chickens is the
growing occurrence of public and guided bird watching tours of leks
during the breeding season. The site-specific impact of recreational
observations of lesser prairie-chicken at leks is currently unknown but
daily human disturbance could reduce mating activities, possibly
leading to a reduction in total production. However, disturbance
effects are likely to be minimal at the population level if disturbance
is avoided by observers remaining in vehicles or blinds until lesser
prairie-chickens naturally
[[Page 73878]]
disperse from the lek and observations are confined to a limited number
of days and leks. Solitary leks comprising fewer than ten males are
most likely to be affected by repeated recreational disturbance.
Suminski (1977, p. 70) strongly encouraged avoidance of activities that
could disrupt nesting activities. Research is needed to quantify this
potential threat to local populations of lesser prairie-chickens.
In summary, it is possible that harvest of lesser prairie-chickens
through sport hunting might be contributing to a decline of some
populations, but we have no information that shows whether this is
actually occurring and no basis on which to estimate whether hunting is
contributing to decline in some areas. However, as populations continue
to decline and become more fragmented, the influence of sport harvest
likely will increase the degree of threat. Public viewing of leks tends
to be limited, primarily due to a general lack of public knowledge of
lek locations and difficulty accessing leks located on private lands.
We expect the States will continue to conduct annual lek counts, which
contributes to a temporary disturbance when the birds are flushed
during attempts to count birds attending the leks. However these
disturbances are intermittent and do not occur repeatedly throughout
the lekking period. Research on lesser prairie-chickens may result in
some capture and handling of the species. Capture-induced stress may
occur and could lead to isolated instances of mortality or injury to
individual birds. But such research is not widespread and likely does
not cause significant population-level impacts. Research is not
anticipated to result in loss of habitat, leading to impacts from
habitat fragmentation. We are not aware of any other forms of
utilization that are negatively impacting lesser prairie-chicken
populations. There is currently no known, imminent threat of take
attributed to collection or illegal harvest for this species.
Consequently, we conclude that overutilization at current population
and harvest levels does not pose a threat to the species.
Other Factors
A number of other factors, although they do not directly contribute
to habitat loss or fragmentation, can influence the survival of the
lesser prairie-chicken. These factors, in combination with habitat loss
and fragmentation, likely influence the persistence of the species.
Nest Parasitism and Competition by Exotic Species
Ring-necked pheasants (Phasianus colchicus) are nonnative species
that overlap the occupied range of the lesser prairie-chicken in Kansas
and portions of Colorado, Oklahoma, Texas (Johnsgard 1979, p. 121), and
New Mexico (Allen 1950, p. 106). Hen pheasants have been documented to
lay eggs in the nests of several bird species, including lesser
prairie-chicken and greater prairie-chicken (Hagen et al. 2002, pp.
522-524; Vance and Westemeier 1979, p. 223; Kimmel 1987, p. 257;
Westemeier et al. 1989, pp. 640-641; Westemeier et al. 1998, 857-858).
Consequences of nest parasitism vary, and may include abandonment of
the host nest, reduction in number of host eggs, lower hatching
success, and parasitic broods (Kimmel 1987, p. 255). Because pheasant
eggs hatch in about 23 days, the potential exists for lesser prairie-
chicken hens to cease incubation, begin brooding, and abandon the nest
soon after the first pheasant egg hatches. Nests of greater prairie-
chickens parasitized by pheasants have been shown to have lower egg
success and higher abandonment than unparasitized nests, suggesting
that recruitment and abundance may be impacted (Westemeier et al. 1998,
pp. 860-861). Predation rates also may increase with incidence of nest
parasitism (Vance and Westemeier 1979, p. 224). Further consequences
are hypothesized to include the imprinting of the pheasant young from
the parasitized nest to the host species, and later attempts by male
pheasants to court females of the host species (Kimmel 1987, pp. 256-
257). Male pheasants have been observed disrupting the breeding
behavior of greater prairie-chickens on leks (Sharp 1957, pp. 242-243;
Follen 1966, pp. 16-17; Vance and Westemeier 1979, p. 222). In
addition, pheasant displays toward female prairie-chickens almost
always cause the female to leave the lek (Vance and Westemeier 1979, p.
222). Thus, an attempt by a male pheasant to display on a prairie-
chicken lek could disrupt the normal courtship activities of prairie-
chickens.
Few published accounts of lesser prairie-chicken nest parasitism by
pheasants exist (Hagen et al. 2002, pp. 522-524), although biologists
from KPWD, ODWC, Sutton Center, TPWD, and the Oklahoma Cooperative Fish
and Wildlife Research Unit have given more than 10 unpublished accounts
of such occurrences. Westemeier et al. (1998, p. 858) documented
statistically that for a small, isolated population of greater prairie-
chickens in Illinois, nest parasitism by pheasants significantly
reduced the hatchability of nests. Based on their findings, they submit
that, in areas with high pheasant populations, the survival of
isolated, remnant flocks of prairie-chicken may be enhanced by
management intervention to reduce nest parasitism by pheasants
(Westemeier et al. 1998, p. 861). While Hagen et al. (2002, p. 523)
documented a rate of only 4 percent parasitism (3 of 75 nests) of
lesser prairie-chicken nests in Kansas, the sample size was small and
may not reflect actual impacts across larger time, geographic, and
precipitation scales. Competition with and parasitism by pheasants may
be a potential factor that could negatively affect vulnerable lesser
prairie-chicken populations at the local level, particularly if
remaining native rangelands become increasingly fragmented (Hagen et
al. 2002, p. 524). More research is needed to understand and quantify
impacts of pheasants on lesser prairie-chicken populations range wide.
Hybridization
The sympatric (overlapping) occupation of habitat and leks by
greater prairie-chickens and lesser prairie-chickens in portions of
central and northwestern Kansas may pose a limited but potential threat
to the species in that region. Hybridization could lead to
introgression (infiltration of the genes of one species into the gene
pool of another through repeated backcrossing) and reduced reproductive
potential; however, hybridization has not been confirmed in these two
species (Bain and Farley 2002, pp. 684, 686). Historical records
document that the species' ranges overlapped, but that habitat
partitioning was clearly evident based on the abundance of sand-adapted
vegetation. The relative frequency of natural hybridization prior to
EuroAmerican settlement is unknown. Currently, the incidence of
hybridization between greater prairie-chickens and lesser prairie-
chickens appears very low, typically less than 1 percent. The
occurrence of hybridization also is restricted to a small portion,
about 250,000 ha (617,000 ac), of the overall current range (Bain and
Farley 2002, p. 684). Because current populations north of the Arkansas
River in Kansas are generally characterized as low density and very
dependent upon the residual habitat structure of fragmented tracts of
CRP lands, those populations may be ephemeral depending on
implementation of CRP projects and stochastic environmental factors.
Low population density also may increase
[[Page 73879]]
the susceptibility of lesser prairie-chickens to hybridization and
exacerbate the potentially negative effects of hybridization. To date,
the fertility of hybrid individuals throughout subsequent generations
has not been rigorously tested. The immediate and long-term influence
of hybridization on the species is unknown and warrants investigation.
Reduced Population Size and Lek Mating System
A number of harmful effects, such as reduced reproductive success
and loss of genetic variation and diversity, become more evident as
population sizes decline. These effects may be exacerbated by the lek
mating system characteristic of many prairie grouse species. Factors
such as high visibility, good auditory projection, and lack of ambient
noise are known to influence selection of lek sites by prairie
chickens, and such factors likely assist females in locating the mating
grounds (Gregory et al. 2011, p. 29). Johnsgard (2002, p. 129) stressed
that the mating system used by prairie grouse works most effectively
when populations are dense enough to provide the visual and acoustic
stimuli necessary to attract prebreeding females to the lek. Once
established, the lek must then be large enough to assure that the
matings will be performed by the most physically and genetically fit
males. Lek breeding already tends to promote inbreeding owing to the
limitations caused by relatively few males siring offspring. The
tendency of female lesser prairie-chicken and other prairie grouse to
typically nest near a lek other than the one on which they mated is an
innate mechanism that can help reduce the effects of inbreeding. The
remaining small and fragmented lesser prairie-chicken populations which
exist over portions of the currently occupied range indicate that such
harmful effects may already be, or soon will be, occurring.
Anthropogenic habitat deterioration and fragmentation not only
leads to range contractions and population extinctions but also may
also have significant genetic and, thus, evolutionary consequences for
the surviving populations. As populations contract and distances
between populations increase, opportunities for gene flow are reduced.
Specifically, Pruett et al. (2009b, p. 258) discussed the influence of
population connectivity, or lack thereof, on the lesser prairie-
chicken. They concluded that lesser prairie-chicken populations were
connected historically, as evidenced by the lack of geographic
variation in morphology and the available genetic information which
suggests that the populations were contiguous and gene flow occurred
among the extant populations. However, Johnson (2008, p. 171) reported
that his results indicate that gene flow is currently restricted
between lesser prairie-chicken populations in New Mexico and Oklahoma.
These findings are not unexpected given information on lesser prairie-
chicken movements. Pruett et al. (2009b, p. 258) report findings by the
Sutton Center that lesser prairie-chickens in Oklahoma were observed to
move as much as 20 to 30 km (12 to 19 mi), but the extant lesser
prairie-chicken populations in New Mexico and Oklahoma are separated by
more than 200 km (124 mi). Given the limited movements of individual
lesser prairie-chickens and the distance between these two populations,
Pruett et al. (2009b, p. 258) considered interaction between these
populations to be highly unlikely. Johnson (2008, p. 171) speculated
that the observed estimate of gene flow between the New Mexico and
Oklahoma populations could be due to effects of recent genetic drift
(change in the genetic composition of a population due to chance
events) as habitat fragmentation and isolation developed between the
New Mexico and Oklahoma populations. Further examination of the
viability of existing lesser prairie-chicken populations will be needed
to thoroughly describe the effects of small population size and
isolation on persistence of the lesser prairie-chicken.
Surface Water Impoundments
Dams have been constructed on streams within the range of the
lesser prairie-chicken to produce impoundments for flood control, water
supply, and other purposes. The impounded waters flood not only
affected stream segments and riparian areas, but also adjacent areas of
grassland and shrubland habitats. Although lesser prairie-chickens may
make use of free-standing water, as is retained in surface
impoundments, its availability is not critical for survival of the
birds (Giesen 1998, p. 4).
The historical range of the lesser prairie-chicken contains
approximately 25 large impoundments with a surface area greater than
1,618 ha (4,000 ac), the largest 20 of these (and their normal surface
acreage) are listed from largest to smallest in Table 3, below.
Table 3--Impoundments With Surface Acreage Greater Than 1,618 ha (4,000
ac) Within the Historical Range of the Lesser Prairie-Chicken
------------------------------------------------------------------------
Impoundment Surface acreage State
------------------------------------------------------------------------
John Martin Reservoir......... 8,302 ha (20,515 ac).. Colorado.
O. H. Ivie Lake............... 7,749 ha (19,149 ac).. Texas.
Lake Meredith................. 6,641 ha (16,411 ac).. Texas.
Lake Kemp..................... 6,309 ha (15,590 ac).. Texas.
Lake Arrowhead................ 6,057 ha (14,969 ac).. Texas.
E. V. Spence Reservoir........ 6,050 ha (14,950 ac).. Texas.
Hubbard Creek Reservoir....... 6,038 ha (14,922 ac).. Texas.
Twin Buttes Reservoir......... 3,965 ha (9,800 ac)... Texas.
Cheney Reservoir.............. 3,859 ha (9,537 ac)... Kansas.
Wilson Lake................... 3,642 ha (9,000 ac)... Kansas.
Foss Lake..................... 3,561 ha (8,800 ac)... Oklahoma.
Great Salt Plains Lake........ 3,516 ha (8,690 ac)... Oklahoma.
Ute Reservoir................. 3,318 ha (8,200 ac)... New Mexico.
Canton Lake................... 3,201 ha (7,910 ac)... Oklahoma.
J. B. Thomas Reservoir........ 2,947 ha (7,282 ac)... Texas.
Cedar Bluff Reservoir......... 2,779 ha (6,869 ac)... Kansas.
Lake Brownwood................ 2,626 ha (6,490 ac)... Texas.
Tom Steed Lake................ 2,590 ha (6,400 ac)... Oklahoma.
Lake Altus-Lugert............. 2,533 ha (6,260 ac)... Oklahoma.
[[Page 73880]]
Lake Kickapoo................. 2,439 ha (6,028 ac)... Texas.
------------------------
Total......................... 88,129 ha (217,772 ac) ................
------------------------------------------------------------------------
(Sources: Kansas Water Office 2012, New Mexico State Parks 2012, Texas
Parks and Wildlife Department 2012, Texas State Historical Association
2012, U.S. Army Corps of Engineers 2012, U.S. Bureau of Reclamation
2012)
In addition, the historical range of the lesser prairie-chicken
contains many smaller impoundments, such as municipal reservoirs and
upstream flood control projects. For example, beginning in the mid-
1900s, the USDA constructed hundreds of small impoundments (floodwater
retarding structures) within the historical range of the lesser
prairie-chicken, through the Watershed Protection and Flood Prevention
Program. The program was implemented to its greatest extent in Oklahoma
(Oklahoma Conservation Commission 2005), and, within the portion of the
lesser prairie-chicken's historical range in that State, the USDA
constructed 574 floodwater retarding structures, totaling 6,070 ha
(15,001 ac) (Elsener 2012). Similarly, within the portion of the lesser
prairie-chicken's historical range in Texas, the USDA constructed 276
floodwater retarding structures, totaling 8,293 surface acres (Bednarz
2012). In Kansas, considerably fewer floodwater retarding structures
were constructed within the historical range, totaling some 857 ha
(2,118 ac) (Gross 2012). Even fewer such structures were constructed in
Colorado and New Mexico.
Cumulatively, the total area of historical lesser prairie-chicken
range lost due to construction of large, medium, and small impoundments
is about 98,413 ha (243,184 ac), yet likely less than the amount of
habitat lost or degraded by other factors discussed in this proposed
rule (e.g., conversion of rangeland to cropland and overgrazing). The
Service expects a large majority of existing reservoirs to be
maintained over the long term. Therefore, these structures will
continue to displace former areas of lesser prairie-chicken habitat, as
well as fragment surrounding lands as habitat for the lesser prairie-
chicken. However, because extensive new dam construction is not
anticipated within the lesser prairie-chicken's range, the Service
considers it unlikely that this threat will increase in the future.
In summary, several other natural or manmade factors are affecting
the continued existence of the lesser prairie-chicken. Parasitism of
lesser prairie-chicken nests by pheasants and hybridization with
greater prairie chickens has been documented but the incidence remains
low. The influence of the above factors on lesser prairie-chicken
survival is expected to remain low unless populations continue to
decline. Low population density can increase the susceptibility of
lesser prairie-chicken to possible genetic effects and increase the
negative effects of hybridization, nest parasitism, and competition.
The effects of certain natural and manmade factors are considered a
threat to the lesser prairie-chicken.
Effects of Existing Regulatory Mechanisms
Regulatory mechanisms, such as Federal, state, and local land use
regulation or laws, may provide protection from some threats provided
those regulations and laws are not discretionary and are enforceable.
In 1973, the lesser prairie-chicken was listed as a threatened
species in Colorado under the State's Nongame and Endangered or
Threatened Species Conservation Act. While this designation prohibits
unauthorized take, possession, and transport, no protections are
provided for destruction or alteration of lesser prairie-chicken
habitat. In the remaining States, the lesser prairie-chicken is
classified as a game species, although the legal harvest is now closed
in New Mexico, Oklahoma, and Texas. Accordingly, the State conservation
agencies have the authority to regulate possession of the lesser
prairie-chicken, set hunting seasons, and issue citations for poaching.
For example, Texas Statute prohibits the destruction of nests or eggs
of game birds such as the lesser prairie-chicken. These authorities
provide lesser prairie-chickens with protection from direct mortality
caused by hunting and prohibit some forms of unauthorized take.
In July of 1997, the NMDGF received a formal request to commence an
investigation into the status of the lesser prairie-chicken within New
Mexico. This request began the process for potential listing of the
lesser prairie-chicken under New Mexico's Wildlife Conservation Act. In
1999, the recommendation to list the lesser prairie-chicken as a
threatened species under the Wildlife Conservation Act was withdrawn
until more information was collected from landowners, lessees, and land
resource managers who may be affected by the listing or who may have
information pertinent to the investigation. In late 2006, NMDGF
determined that the lesser prairie-chicken would not be State-listed in
New Mexico. New Mexico's Wildlife Conservation Act, under which the
lesser prairie-chicken could have been listed, offers little
opportunity to prevent otherwise lawful activities, including many of
the activities previously discussed.
Regardless of each State's listing status, most occupied lesser
prairie-chicken habitat throughout its current range occurs on private
land (Taylor and Guthery 1980b, p. 6), where State conservation
agencies have little authority to protect or direct management of the
species' habitat. All five States in occupied range have incorporated
the lesser prairie-chicken as a species of conservation concern and
management priority in their respective State Wildlife Action Plans.
While identification of the lesser prairie-chicken as a species of
conservation concern does help heighten public awareness, this
designation provides no protection from direct take or habitat
destruction or alteration.
Some States, such as Oklahoma, have laws and regulations that
address use of State school lands, primarily based on maximizing
financial return from operation of these lands. However, the scattered
nature of these lands and requirement to maximize financial returns
minimize the likelihood that these lands will be managed to reduce
degradation and fragmentation of habitat and ensure the conservation of
the species.
Lesser prairie-chickens are not covered or managed under the
provisions of the Migratory Bird Treaty Act (16 U.S.C. 703-712) because
they are considered resident game species. The lesser prairie-chicken
has an
[[Page 73881]]
International Union for Conservation of Nature (IUCN) Red List Category
of ``vulnerable'' (BirdLife International 2008), and NatureServe
currently ranks the lesser prairie-chicken as G3--Vulnerable
(NatureServe 2011, entire). The lesser prairie-chicken also is on the
National Audubon Society's WatchList 2007 Red Category, which is ``for
species that are declining rapidly or have very small populations or
limited ranges, and face major conservation threats.'' However, none of
these designations provide any regulatory protection.
There are six National Grasslands located within the historical
range of the lesser prairie-chicken. The National Grasslands are
managed by the USFS, have been under Federal ownership since the late
1930s, and were officially designated as National Grasslands in 1960.
The Kiowa, Rita Blanca, Black Kettle, and McClellan Creek National
Grasslands are administered by the Cibola National Forest. The Kiowa
National Grassland covers 55,659 ha (137,537 ac) and is located within
Mora, Harding, Union, and Colfax Counties, New Mexico. The Rita Blanca
National Grassland covers 37,631 ha (92,989 ac) and is located within
Dallam County, Texas, and Cimarron County, Oklahoma. The Black Kettle
National Grassland covers 12,661 ha (31,286 ac) and is located within
Roger Mills County, Oklahoma, and Hemphill County, Texas. The McClellan
Creek National Grassland covers 586 ha (1,449 ac) and is located in
Gray County, Texas. No breeding populations of lesser prairie-chickens
are known to occur on these holdings.
The Comanche and Cimarron National Grasslands are under the
administration of the Pike and San Isabel National Forest. The Comanche
National Grassland covers 179,586 ha (443,765 ac) and is located within
Baca, Las Animas, and Otero Counties, Colorado. The Cimarron National
Grassland covers 43,777 ha (108,175 ac) and is located in Morton and
Stevens Counties, Kansas. Both of these areas are known to support
breeding lesser prairie-chickens.
The National Forest Management Act of 1976 and the associated
planning rule in effect at the time of planning initiation are the
principal law and regulation governing the planning and management of
National Forests and National Grasslands by the USFS. In 2008, a new
National Forest System Land Management Planning Rule (36 CFR Part 219)
took effect and was used to guide the development of a Land and
Resource Management Plan for the Comanche and Cimarron National
Grasslands. That plan was one of the first plans developed and released
under the 2008 planning rule. The predecisional review version of the
Cimarron and Comanche National Grasslands Land Management Plan was made
available to the public on October 17, 2008. The lesser prairie-chicken
was included as a species-of-concern in accordance with guidance
available in the existing planning rule (USFS 2008, p. 35). As defined
in the 2008 planning rule, species-of-concern are 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). Identification of the lesser prairie-chicken as a species-of-
concern in the Cimarron and Comanche National Grasslands Land
Management Plan led to inclusion of planning objectives targeting
improvement of the species' habitat, as described below.
Planning for the Kiowa, Rita Blanca, Black Kettle, and McClellan
Creek National Grasslands was well underway when the 2008 National
Forest System Land Management Planning Rule was enjoined on June 30,
2009, by the United States District Court for the Northern District of
California (Citizens for Better Forestry v. United States Department of
Agriculture, 632 F. Supp. 2d 968 (N.D. Cal. June 30, 2009)). A new
planning rule was finalized in 2012 (77 FR 67059) and became effective
on May 9, 2012. The transition provisions of the 2012 planning rule (36
CFR 219.17(b)(3)) allow those National Forest System lands that had
initiated plan development, plan amendments, or plan revisions prior to
May 9, 2012, to continue using the provisions of the prior planning
regulation. The Cibola National Forest elected to use the provisions of
the 1982 planning rule, including the requirement to prepare an
Environmental Impact Statement, to complete its plan development for
the Kiowa, Rita Blanca, Black Kettle, and McClellan Creek National
Grasslands.
The Comanche and Cimarron National Grasslands currently manages the
Comanche Lesser Prairie-chicken Habitat Zoological Area, now designated
as a Colorado Natural Area, which encompasses an area of 4,118 ha
(10,177 ac) that is managed to benefit the lesser prairie-chicken.
Current conditions on this area include existing oil and gas leases,
two-track roads, utility corridors, and livestock grazing. Wildfires on
the area have been suppressed over the last 30 years. The area provides
a special viewing area for the lesser prairie-chicken, which has been
closed to protect lekking activities. The plan specifies that the
desired future condition of the area would be to retain habitat
conditions suitable for the lesser prairie-chicken. Specifically, the
objectives of the plan identify steps that would be taken over the next
15 years to achieve the desired conditions. One objective would be to
retain a minimum of 6,665 ha (16,470 ac) of sand sagebrush prairie
ecosystem for the lesser prairie-chicken. Within the Comanche Lesser
Prairie-chicken Habitat Zoological Area, over the next 15 years, a
minimum of 202 ha (500 ac) would be treated to increase native plant
diversity.
Design criteria identified in the current Cimarron and Comanche
National Grasslands Land Management Plan for management of the sand
sagebrush prairie include: (1) Limited construction of new structures
or facilities typically within 3.2 km (2 mi) of known lesser prairie-
chicken leks or populations if those structures and facilities would
negatively impact the lesser prairie-chicken; (2) protection of leks,
nesting habitat, and brood rearing habitat from surface disturbances
(e.g., dog training, drilling, and various forms of construction)
between March 15 to July 15; and (3) provision for adequate residual
cover during nesting periods. Within the Comanche Lesser Prairie-
Chicken Habitat Zoological Area, design criteria include limiting or
using livestock grazing in a manner that does not negatively impact
lesser prairie-chicken nesting habitat. The USFS also committed to
monitoring any changes in distribution and abundance of the lesser
prairie-chicken on the National Grasslands.
Prior planning regulations included a requirement for the USFS to
identify species as management indicator species, if their population
changes were believed to be indicative of the effects of management
activities (36 CFR 219.19). Under the 2008 regulations, the concept of
management indicator species was not included in the final rule. The
2008 planning regulations instead chose to use ``species-of-concern''.
Species that were identified as proposed and candidate species under
the Endangered Species Act were classified as species-of-concern. The
primary purpose of identifying species-of-concern was to put in place
provisions that would have contributed to keeping those species from
being listed as threatened or endangered species. As explained above,
the transition provisions (36 CFR 219.17(b)(3)) of the 2012 planning
rule allow the use of the provisions of the 1982 planning rule,
including the requirement that management indicator species be
identified as part of the plan.
[[Page 73882]]
Management indicator species serve multiple functions in forest
planning: Focusing management direction developed in the alternatives,
providing a means to analyze effects on biological diversity, and
serving as a reliable feedback mechanism during plan implementation.
The latter often is accomplished by monitoring population trends in
relationship to habitat changes. Although suitable habitat is present,
no breeding populations of lesser prairie-chickens are known from the
Kiowa, Rita Blanca, Black Kettle, and McClellan Creek National
Grasslands. Consequently, the lesser prairie-chicken is not designated
as a management indicator species in the plan. Instead the lesser
prairie-chicken is included on the Regional Forester's sensitive
species list and as an At-Risk species.
The USFS also contracted with lesser prairie-chicken experts to
prepare a succinct evaluation of species of potential viability
concern, addressing eight factors pertinent to species viability. A
Technical Conservation Assessment for the lesser prairie-chicken (Robb
and Schroeder 2005, p. 8) was completed and confirms the need to retain
sensitive species status designation for the lesser prairie-chicken.
Species conservation assessments produced as part of the Species
Conservation Project are designed to provide land managers, biologists,
and the public with a thorough discussion of the biology, ecology,
conservation, and management of the lesser prairie-chicken based on
existing scientific knowledge. The assessment goals limit the scope of
the work to summaries of scientific knowledge, discussion of broad
implications of that knowledge, and outlines of information needs. The
assessment does not seek to develop specific prescriptions for
management of populations and habitats. Instead, it is intended to
provide the ecological background upon which management should be based
and focuses on the consequences of changes in the environment that
result from management (i.e., management implications). This
comprehensive document can be found on the internet at http://www.fs.fed.us/r2/projects/scp/assessments/lesserprairiechicken.pdf.
The other primary Federal surface ownership of lands occupied by
the lesser prairie-chicken is administered by the BLM in New Mexico. In
New Mexico, roughly 41 percent of the known historical and most of the
currently occupied lesser prairie-chicken range occurs on BLM land. The
BLM currently manages approximately 342,969 surface ha (847,491 ac)
within lesser prairie-chicken range in eastern New Mexico. They also
oversee another 120,529 ha (297,832 ac) of Federal minerals below
private surface ownership. The core of currently occupied lesser
prairie-chicken habitat in New Mexico is within the Roswell BLM
Resource Area. However, the Carlsbad BLM Resource Area comprised much
of the historical southern periphery of the species' range in New
Mexico. The BLM's amended RMPA (BLM 2008, pp. 5-31) provides some
limited protections for the lesser prairie-chicken in New Mexico by
reducing the number of drilling locations, decreasing the size of well
pads, reducing the number and length of roads, reducing the number of
powerlines and pipelines, and implementing best management practices
for development and reclamation. Implementation of these protective
measures, particularly curtailment of new mineral leases, would be
greatest in the Core Management Area and the Primary Population Area
habitat management units (BLM 2008, pp. 9-11). The Core Management and
Primary Population Areas are located in the core of the lesser prairie-
chicken occupied range in New Mexico. The effect of these best
management practices on the status of the lesser prairie-chicken is
unknown, particularly considering some 60,000 ha (149,000 ac) have
already been leased in those areas (BLM 2008, p. 8). The effectiveness
of the amended RMPA is hampered by a lack of explicit measures designed
to improve the status of the lesser prairie-chicken, limited certainty
that resources will be available to carry out the management plan,
limited regulatory or procedural mechanisms in place to carry out the
efforts, lack of monitoring efforts, and provision for exceptions to
the best management practices under certain conditions, which could
negate the benefit of the conservation measures.
The amended RMPA stipulates that implementation of measures
designed to protect the lesser prairie-chicken and dunes sagebrush
lizard may not allow approval of all spacing unit locations or full
development of a lease (BLM 2008, p. 8). In addition, the RMPA
prohibits drilling and exploration in lesser prairie-chicken habitat
between March 1 and June 15 of each year (BLM 2008, p. 8). No new
mineral leases will be issued on approximately 32 percent of Federal
mineral acreage within the RMPA planning area (BLM 2008, p. 8),
although some exceptions are allowed on a case-by-case basis (BLM 2008,
pp. 9-11). Within the Core Management Area and Primary Population Area,
new leases will be restricted in occupied and suitable habitat;
however, if there is an overall increase in reclaimed to disturbed
acres over a 5-year period, new leases in these areas will be allowed
(BLM 2008, p. 11). Considering Hunt and Best (2004, p. 92) concluded
that petroleum development at intensive levels likely is not compatible
with populations of lesser prairie-chicken, additional development in
the Core Management Area and Primary Population Area habitat management
units may hinder long-term conservation of the species in New Mexico.
The RMPA allows lease applicants to voluntarily participate in a power
line removal credit to encourage removal of idle power lines (BLM 2008,
pp. 2-41). In the southernmost habitat management units, the Sparse and
Scattered Population Area and the Isolated Population Area, where
lesser prairie-chickens are now far less common than in previous
decades (Hunt and Best 2004), new leases will not be allowed within 2.4
km (1.5 mi) of a lek (BLM 2008, p. 11).
The ineffectiveness of certain imposed energy development
stipulations near leks for the purpose of protecting grouse on Federal
lands has been recently confirmed for sage grouse. Holloran (2005, p.
57) and Naugle et al. (2006a, p. 3) documented that sage grouse avoid
energy development (coalbed methane) not only in breeding and nesting
habitats, but also in wintering habitats. They assert that current best
management practices in use by Federal land management agencies that
place timing stipulations or limit surface occupancy near greater sage-
grouse leks result in a human footprint that far exceeds the tolerance
limits of sage grouse. Ultimately, they recommended that effective
conservation strategies for grouse must limit the cumulative impact of
habitat disturbance, modification, and destruction in all habitats and
at all times of the year (Holloran 2005, p. 58; Naugle et al. 2006b, p.
12). Additional research on the effect of petroleum development on
lesser prairie-chicken is needed. However, available information on the
lesser prairie-chicken (Suminski 1977, p. 70; Hagen et al. 2004, pp.
74-75; Hunt and Best 2004, p. 92; Pitman et al. 2005, pp. 1267-1268)
indicates that the effect is often detrimental, particularly during the
breeding season.
Because only about 4 percent of the species' overall range occurs
on Federal lands, the Service recognizes that the lesser prairie-
chicken cannot be fully recovered on Federal lands alone. However, no
laws or regulations
[[Page 73883]]
currently protect lesser prairie-chicken habitat on private land, aside
from State harvest restrictions. Therefore, the Service views decisions
regarding the management and leasing of Federal lands and minerals
within existing lesser prairie-chicken range as important to the future
conservation and persistence of the species.
Since 2004, the construction of commercial wind energy projects
near and within occupied lesser prairie-chicken habitat has raised
concerns about the potential negative effects such projects may have on
the species, if constructed at large scales in occupied range. As
discussed previously, a rapid expansion of transmission lines and
associated wind energy development throughout large portions of
occupied lesser prairie-chicken range is occurring. Because most wind
development activities are privately funded and are occurring on
private land, wind energy siting, development, and operation falls
outside the purview of the National Environmental Policy Act of 1969
(NEPA) and other Federal conservation statues and regulatory processes.
As a result, little opportunity for timely and appropriate
environmental review and consultation by Federal, state, and local
conservation entities exists.
The current lack of regulatory oversight and public notice
requirements for the purchase of wind rights and construction of wind
generation and related transmission facilities is a concern.
Specifically, the Service is unaware of any state or Federal mechanisms
that require potential wind energy producers to disclose the location,
size, and anticipated construction date for pending projects or require
analysis under the provisions of the NEPA. Lacking the ability to
obtain pertinent siting information or analyze alternative siting
locations, neither the Service nor State conservation agencies have the
ability to accurately influence the size or timing of wind generation
construction activities within occupied lesser prairie-chicken habitat.
In summary, most occupied lesser prairie-chicken habitat occurs on
private land, where State conservation agencies have little authority
to protect lesser prairie-chicken or facilitate and monitor management
of lesser prairie-chicken habitat beyond regulating recreational
harvest. Because most lesser prairie-chicken habitat destruction and
modification on private land occurs through otherwise lawful activities
such as agricultural conversion, livestock grazing, energy development,
and fire exclusion, few (if any) regulatory mechanisms are in place to
substantially alter human land uses at a sufficient scale to protect
lesser prairie-chicken populations and their habitat. While almost no
regulatory protection is in place for the species, regulatory
incentives, in the form of county, state, and national legislative
actions, have been created to facilitate the expansion of activities
that result in fragmentation of occupied lesser prairie-chicken
habitat, such as that resulting from oil, gas, and wind energy
development. For the remaining 4 percent of occupied habitat currently
under Federal management, habitat quality depends primarily on factors
related to multiple use mandates, such as livestock grazing and oil,
gas, and wind power development activities. Because prior leasing
commitments and management decisions on the majority of occupied
parcels of Federal land offer little flexibility for reversal, any new
regulatory protection for uncommitted land units are important and will
take time to achieve substantial benefits for the species in the long
term.
We note that the existing regulatory mechanisms at the Federal and
State level have not been sufficient to preclude the decline of the
species. In spite of the existing regulatory mechanisms, the current
and projected threat from the loss and fragmentation of lesser prairie-
chicken habitat and range is still ongoing.
Proposed Listing Determination
As required by the Act, we considered the five factors in assessing
whether the lesser prairie-chicken meets the definition of a threatened
or endangered species. We examined the best scientific and commercial
information available regarding the past, present, and future threats
faced by the lesser prairie-chicken. Based on our review of the best
available scientific and commercial information, we find the lesser
prairie-chicken is likely to become in danger of extinction in the
foreseeable future and therefore meets the definition of a threatened
species.
The life history and ecology of the lesser prairie-chicken makes it
exceptionally vulnerable to changes on the landscape. As discussed
above, the lek breeding system which requires males and females to be
able to hear and see each other over relatively wide distances, the
need for large patches of habitat that include several types of
microhabitats, and the behavioral avoidance of vertical structures make
the lesser prairie-chicken vulnerable to habitat impacts, especially at
its currently reduced numbers. Specifically, its behavioral avoidance
of vertical structures causes its habitat to be more functionally
fragmented than another species' habitat would be. For example, a snake
likely would continue to use habitat underneath a wind turbine, but the
lesser prairie-chicken's predator avoidance behavior causes it to avoid
a large area (estimated to be a mile) around a tall vertical object.
The habitat within that 1.6-km (1-mi) buffer continues to be otherwise
suitable for lesser prairie-chickens, but the entire area is avoided
because of the vertical structure. As a result, the impact of any
individual fragmenting feature is of higher magnitude than the physical
footprint of that structure would suggest it should be.
The historical, current, and ongoing threats to the lesser prairie-
chicken are widespread and of high magnitude. The lesser prairie-
chicken is currently imperiled throughout all of its range due to
historical, ongoing impacts and probable future impacts of the
cumulative habitat loss and fragmentation. These impacts are the result
of conversion of grasslands to agricultural uses, encroachment by
invasive woody plants, wind energy development, petroleum production,
roads, and presence of manmade vertical structures including towers,
utility lines, fences, turbines, wells, and buildings. The historical
and current impact of these fragmenting factors has reduced the status
of the species to the point that individual populations are vulnerable
to extirpation as a result of stochastic events such as extreme weather
events. Additionally, these populations are more vulnerable to the
effects of climate change, disease, and predation than they would have
been at historical population levels. These threats are currently
impacting lesser prairie-chickens throughout their range and are
projected to continue and to increase in severity into the foreseeable
future.
The range of the lesser prairie-chicken has been reduced by an
estimated 84 percent. The vulnerability of lesser prairie-chickens to
changes on the landscape is magnified compared to historical times due
to its reduced population numbers, prevalence of isolated populations,
and reduced range. There are few areas of large patches of
unfragmented, suitable grassland remaining. Based on our analysis
presented earlier, some 99.8 percent of the remaining suitable habitat
patches were less than 2,023 ha (5,000 ac) in size. In order to thrive
and colonize unoccupied areas, lesser prairie-chickens require large
patches of functionally unfragmented habitat that include a variety of
microhabitats needed to support lekking, nesting,
[[Page 73884]]
brood rearing, feeding for young, and feeding for adults, among other
things. Habitat patches that do not contain all of these microhabitats
may support population persistence, but may not support thriving
populations that can produce surplus males capable of colonizing new
areas or recolonizing previously extirpated areas.
Due to its reduced population size and ongoing habitat loss and
degradation, the species lacks sufficient redundancy and resiliency to
recover from present and foreseeable future probable threats. As a
result, the status of the species has been reduced to the point that
individual populations are vulnerable to extirpation due to a variety
of stochastic events (e.g., drought, winter storms). These extirpations
are especially significant because, in many places, there are no
nearby, connected populations with robust numbers that can rescue the
extirpated populations (i.e., be a source for recolonization). Without
intervention, population numbers will continue to decline and the range
of the species will continue to contract.
In summary, as a result of the significant reduction in numbers and
range of lesser prairie-chickens resulting from cumulative ongoing
habitat fragmentation, combined with the lack of sufficient redundancy
and resiliency of current populations, we conclude that the lesser
prairie-chicken is currently at risk of extinction or is likely to be
in danger of extinction in the foreseeable future.
We must then assess whether the species is in danger of extinction
now (i.e., an endangered species) or is likely to become in danger of
extinction in the foreseeable future (i.e., a threatened species). In
assessing the status of the lesser prairie-chicken, we applied the
general understanding of ``in danger of extinction'' as discussed in
the December 22, 2010, memo to the Polar Bear Listing Determination
File, ``Supplemental Explanation for the Legal Basis of the
Department's May 15, 2008, Determination of Threatened Status for the
Polar Bear'', signed by then Acting Director Dan Ashe (hereafter
referred to as Polar Bear Memo). As discussed in the Polar Bear Memo, a
key statutory difference between a threatened species and an endangered
species is the timing of when a species may be in danger of extinction
(i.e., currently on the brink of extinction), either now (endangered
species) or in the foreseeable future (threatened species). A species
that is in danger of extinction at some point beyond the foreseeable
future does not meet the definition of either an endangered species or
a threatened species.
As discussed in the Polar Bear Memo, because of the fact-specific
nature of listing determinations, there is no single metric for
determining if a species is ``in danger of extinction'' now.
Nonetheless, the practice of the Service over the past four decades has
been remarkably consistent. Species that the Service has determined to
be in danger of extinction now, and therefore appropriately listed as
an endangered species, generally fall into four basic categories. The
best scientific data available indicates that the lesser prairie-
chicken fits into the category: ``Species with still relatively
widespread distribution that have nevertheless suffered ongoing major
reductions in its numbers, range, or both, as a result of factors that
have not been abated.'' However, the Polar Bear Memo goes on to explain
that threatened species share some characteristics with this category
of endangered species, ``Whether a species in this situation is
ultimately an endangered species or threatened species depends on the
specific life history and ecology of the species, the natures of the
threats, and population numbers and trends.''
As discussed above, the foreseeable future refers to the extent to
which the Secretary can reasonably rely on predictions about the future
in making determinations about the future conservation status of the
species. For the lesser prairie-chicken, information about the primary
ongoing and future threats is reasonably well-known and reliable. As
suggested by the Polar Bear Memo, species like the lesser prairie-
chicken that have suffered ongoing major reductions in numbers and
range due to factors that have not been abated may be classified as a
threatened species if some populations appear stable, which would
indicate that the entity as a whole was not in danger of extinction now
(i.e., not an endangered species). In the case of the lesser prairie-
chicken, the best available information indicates that while there have
been major range reductions (84 percent) as a result of factors that
have not been abated (cumulative habitat fragmentation) and while there
continues to be uncertainty around the current status of the species,
particularly in the face of significant drought events in 2011 and
2012, there may be sufficient stable populations to allow the species
to persist into the near future. The remaining populations are spread
over a large geographical area and the current range of the species
includes populations that represent the known diversity of ecological
settings for the lesser prairie-chicken. As a result, it is unlikely
that a single stochastic event (e.g., drought, winter storm) will
affect all known extant populations equally or simultaneously,
therefore, it would require several stochastic events over a number of
years to bring the lesser prairie-chicken to the brink of extinction
due to those factors alone. Similarly, the current and ongoing threats
of conversion of grasslands to agricultural uses, encroachment by
invasive woody plants, wind energy development, and petroleum
production are not likely to impact all remaining populations
significantly in the near term because these activities either move
slowly across the landscape or take several years to plan and
implement. Therefore, because there may be sufficient stable
populations to allow the lesser prairie-chicken to persist into the
near future, it is not in danger of extinction throughout all of its
range now, and more appropriately meets the definition of a threatened
species (i.e., likely to become in danger of extinction in the
foreseeable future).
In conclusion, as described above, the lesser prairie-chicken has
experienced significant reductions in range and population numbers, is
especially vulnerable to impacts due to its life history and ecology,
and is subject to significant current and ongoing threats in the
foreseeable future. However, there may be sufficient stable populations
to allow the species to persist into the near future. Therefore, after
a review of the best available scientific information as it relates to
the status of the species and the five listing factors, we find the
lesser prairie-chicken is likely to become in danger of extinction in
the foreseeable future throughout its range.
Critical Habitat Designation for Lesser Prairie-Chicken
Background
Critical habitat is defined in section 3 of the Act as:
(i) The specific areas within the geographical area occupied by the
species, at the time it is listed in accordance with the Act, on which
are found those physical or biological features:
(I) Essential to the conservation of the species, and
(II) Which may require special management considerations or
protection; and
(ii) Specific areas outside the geographical area occupied by the
species at the time it is listed, upon a determination that such areas
are essential for the conservation of the species.
[[Page 73885]]
Conservation, as defined under section 3 of the Act, means using
all methods and procedures deemed necessary to bring an endangered or
threatened species to the point at which the measures provided pursuant
to the Act are no longer necessary. Such methods and procedures
include, but are not limited to, all activities associated with
scientific resources management such as research, census, law
enforcement, habitat acquisition and maintenance, propagation, live
trapping, and transplantation, and, in the extraordinary case where
population pressures within a given ecosystem cannot be relieved
otherwise, may include regulated taking.
Critical habitat receives protection under section 7(a)(2) of the
Act through the requirement that Federal agencies insure, in
consultation with the Service, that any action they authorize, fund, or
carry out is not likely to result in the destruction or adverse
modification of critical habitat. The designation of critical habitat
does not alter land ownership or establish a refuge, wilderness,
reserve, preserve, or other conservation area. Such designation does
not allow the government or public to access private lands. Such
designation does not require implementation of restoration, recovery,
or enhancement measures by non-Federal landowners. Instead, where a
landowner seeks or requests Federal agency funding or authorization for
an action that may affect a listed species or critical habitat, the
consultation requirements of section 7(a)(2) would apply, but even in
the event of a destruction or adverse modification finding, the
obligation of the Federal action agency and the applicant is not to
restore or recover the species, but to implement reasonable and prudent
alternatives to avoid destruction or adverse modification of critical
habitat.
Under the first prong of the Act's definition of critical habitat,
areas within the geographical area occupied by the species at the time
it was listed are included in a critical habitat designation if they
contain physical or biological features (1) which are essential to the
conservation of the species and (2) which may require special
management considerations or protection. For these areas, critical
habitat designations identify, to the extent known using the best
scientific and commercial data available, those physical or biological
features that are essential to the conservation of the species (such as
space, food, cover, and protected habitat). In identifying those
physical and biological features within an area, we focus on the
principal biological or physical constituent elements (primary
constituent elements such as roost sites, nesting grounds, seasonal
wetlands, water quality, tide, soil type) that are essential to the
conservation of the species. Primary constituent elements are the
elements of physical or biological features that are the specific
components that provide for a species' life-history processes, are
essential to the conservation of the species.
Under the second prong of the Act's definition of critical habitat,
we can designate critical habitat in areas outside the geographical
area occupied by the species at the time it is listed, upon a
determination that such areas are essential for the conservation of the
species. For example, an area formerly occupied by the species but that
was not occupied at the time of listing may be essential to the
conservation of the species and may be included in a critical habitat
designation. We designate critical habitat in areas outside the
geographical area occupied by a species only when a designation limited
to its current occupied range would be inadequate to ensure the
conservation of the species.
Section 4 of the Act requires that we designate critical habitat on
the basis of the best scientific and commercial data available.
Further, our Policy on Information Standards Under the Endangered
Species Act (published in the Federal Register on July 1, 1994 (59 FR
34271)), the Information Quality Act (section 515 of the Treasury and
General Government Appropriations Act for Fiscal Year 2001 (Pub. L.
106-554; H.R. 5658)), and our associated Information Quality
Guidelines, provide criteria, establish procedures, and provide
guidance to ensure that our decisions are based on the best scientific
data available. They require our biologists, to the extent consistent
with the Act and with the use of the best scientific data available, to
use primary and original sources of information as the basis for
recommendations to designate critical habitat.
When we are determining which areas we should designate as critical
habitat, our primary source of information is generally the information
developed during the listing process for the species. Additional
information sources may include articles published in peer-reviewed
journals, conservation plans developed by States and Counties,
scientific status surveys and studies, biological assessments, or other
unpublished materials and expert opinion or personal knowledge.
Habitat is often dynamic, and species may move from one area to
another over time. Furthermore, we recognize that critical habitat
designated at a particular point in time may not include all of the
habitat areas that we may later determine are necessary for the
recovery of the species, considering additional scientific information
may become available in the future. For these reasons, a critical
habitat designation does not signal that habitat outside the designated
area is unimportant or may not be needed for recovery of the species.
Areas that are important to the conservation of the species, both
inside and outside the critical habitat designation, will continue to
be subject to: (1) Conservation actions implemented under section
7(a)(1) of the Act; (2) regulatory protections afforded by the
requirement in section 7(a)(2) of the Act for Federal agencies to
insure their actions are not likely to jeopardize the continued
existence of any endangered or threatened species; and (3) the
prohibitions of section 9 of the Act if actions occurring in these
areas may result in take of the species. Federally funded or permitted
projects affecting listed species outside their designated critical
habitat areas may still result in jeopardy findings in some cases.
These protections and conservation tools will continue to contribute to
recovery of this species. Similarly, critical habitat designations made
on the basis of the best available information at the time of
designation will not control the direction and substance of future
recovery plans, HCPs, or other species conservation planning efforts if
new information available at the time of these planning efforts calls
for a different outcome.
Prudency Determination
Section 4(a)(3) of the Act, as amended, and implementing
regulations (50 CFR 424.12), require that, to the maximum extent
prudent and determinable, the Secretary designate critical habitat at
the time a species is determined to be an endangered or threatened
species. Our regulations (50 CFR 424.12(a)(1)) state that the
designation of critical habitat is not prudent when one or both of the
following situations exist: (1) The species is threatened by taking or
other human activity, and the identification of critical habitat can be
expected to increase the degree of threat to the species, or (2) such
designation of critical habitat would not be beneficial to the species.
There is currently no operative threat to lesser prairie-chickens
attributed to unauthorized collection or vandalism, and identification
and mapping of critical habitat is not expected to initiate
[[Page 73886]]
any such threat. Thus, we conclude designating critical habitat for the
lesser prairie-chicken is not expected to create or increase the degree
of threat to the species due to taking.
Conservation of lesser prairie-chickens and their essential
habitats will focus on, among other things, habitat management,
protection, and restoration, which will be aided by knowledge of
habitat locations and the physical or biological features of the
habitat. In the absence of finding that the designation of critical
habitat would increase threats to a species, if there are any benefits
to a critical habitat designation, then a prudent finding is warranted.
We conclude that the designation of critical habitat for the lesser
prairie-chicken will benefit the species by serving to focus
conservation efforts on the restoration and maintenance of ecosystem
functions within those areas considered essential for achieving its
recovery and long-term viability. Other potential benefits include: (1)
Triggering consultation under section 7(a)(2) of the Act in new areas
for actions in which there may be a Federal nexus where it would not
otherwise occur because, for example, it is or has become unoccupied or
the occupancy is in question; (2) focusing conservation activities on
the most essential features and areas; (3) providing educational
benefits to State or County governments or private entities; and (4)
preventing inadvertent harm to the species.
Therefore, because we have determined that the designation of
critical habitat will not likely increase the degree of threat to the
species and may provide some benefit, we find that designation of
critical habitat is prudent for the lesser prairie-chicken.
Critical Habitat Determinability
Having determined that designation is prudent, under section
4(a)(3) of the Act we must find whether critical habitat for the
species is determinable. Our regulations at 50 CFR 424.12(a)(2) state
that critical habitat is not determinable when one or both of the
following situations exist:
(i) Information sufficient to perform required analyses of the
impacts of the designation is lacking, or
(ii) The biological needs of the species are not sufficiently well
known to permit identification of an area as critical habitat. When
critical habitat is not determinable, the Act allows the Service an
additional year following publication of a final listing rule to
publish a final critical habitat designation (16 U.S.C.
1533(b)(6)(C)(ii)).
In accordance with section 3(5)(A)(i) and 4(b)(1)(A) of the Act and
the regulations at 50 CFR 424.12, in determining which areas occupied
by the species at the time of listing to designate as critical habitat,
we consider the physical and biological features essential to the
conservation of the species which may require special management
considerations or protection. These include, but are not limited to:
(1) Space for individual and population growth and for normal
behavior;
(2) Food, water, air, light, minerals, or other nutritional or
physiological requirements;
(3) Cover or shelter;
(4) Sites for breeding, reproduction, and rearing (or development)
of offspring; and
(5) Habitats that are protected from disturbance or are
representative of the historical geographical and ecological
distributions of a species.
We are currently unable to identify critical habitat for the lesser
prairie-chicken because important information on the geographical area
occupied by the species, the physical and biological habitat features
that are essential to the conservation of the species, and the
unoccupied areas that are essential to the conservation of the species
is not known at this time. A specific shortcoming of the currently
available information is the lack of data about: (1) The specific
physical and biological features essential to the conservation of the
species; (2) how much habitat may ultimately be needed to conserve the
species; (3) where the habitat patches occur that have the best chance
of rehabilitation; and (4) where linkages between current and future
populations may occur. Additionally, while we have reasonable general
information about habitat features in areas occupied by lesser prairie-
chickens, we do not know what specific features, or combinations of
features, are needed to ensure persistence of stable, secure
populations.
Several conservation actions are currently underway that will help
inform this process and reduce some of the current uncertainty.
Incorporation of the information from these conservation actions will
give us a better understanding of the species' biological requirements
and what areas are needed to support the conservation of the species.
The five State Conservation Agencies within the occupied range of
the lesser prairie-chicken, through coordination with the Western
Association of Fish and Wildlife Agencies Grassland Initiative, have
been funded to develop a rangewide survey sampling framework and to
implement aerial surveys during the spring (March through May) of 2012,
and continuing into 2013. Implementation of these aerial surveys is
important as they will enable biologists to determine location of leks
that are too distant from public roads to be detected during standard
survey efforts. Our critical habitat determination will benefit from
this additional information and allow us to consider the most recent
and best science in making our critical habitat determination.
Similarly, all five State Conservation Agencies within the occupied
range of the lesser prairie-chicken have partnered with the Service and
Playa Lakes Joint Venture, using funding from the DOE and the Western
Governor's Association, to develop a decision support system that
assists in evaluation of lesser prairie-chicken habitat, assists
industry with nonregulatory siting decisions, and facilitates targeting
of conservation activities for the species. The first iteration of that
product, Phase I, went online in September 2011 (http://kars.ku.edu/geodata/maps/sgpchat/). This decision support system is still being
refined, and a second iteration of the product (Phase II), under
oversight of the Western Association of Fish and Wildlife Agencies,
will provide additional information that will help improve evaluation
of lesser prairie-chicken habitat. The Steering Committee of the Great
Plains Landscape Conservation Cooperative has made completion of Phase
II one of their highest priorities for over the next 18 months. The
Lesser Prairie-chicken Interstate Working Group will be identifying the
research and data needs for moving Phase II forward. Outputs derived
from this decision support tool will help us more precisely identify
the location and distribution of features essential to the conservation
of the lesser prairie-chicken.
Additionally, the Service is actively pursuing the development of a
population viability analysis that we anticipate will significantly
inform the development of a critical habitat proposal. A population
viability analysis is a modeling effort that is intended to estimate
the likelihood of persistence of a population or species into the
future. The analysis can be used to assess appropriate population
targets that would be expected to support long term persistence, and
can be used to compare and contrast a variety of potential management
options.
Finally, the five State Conservation Agencies also are working to
develop a
[[Page 73887]]
multi-State rangewide conservation strategy that likely will provide
information on the location of focal areas where targeted conservation
is anticipated to contribute significantly to long-term viability of
the lesser prairie-chicken.
Consequently, while we recognize that the Act requires us to use
the best available scientific information available at any given time
when developing a critical habitat designation, we believe these
additional efforts that are ongoing over the next 6 months or more will
be vital pieces of information that will support a more well-reasoned
critical habitat designation that will better contribute to the
conservation of the species. Therefore, we have concluded that critical
habitat is not determinable for the lesser prairie-chicken at this
time.
Peer Review
In accordance with our joint policy published in the Federal
Register on July 1, 1994 (59 FR 34270), we will seek the expert
opinions of at least three appropriate and independent specialists
regarding this proposed rule. The purpose of such review is to ensure
that our determination of status for this species is based on
scientifically sound data, assumptions, and analyses. We will send peer
reviewers copies of this proposed rule immediately following
publication in the Federal Register. We will invite these peer
reviewers to comment, during the public comment period, on our use and
interpretation of the science used in developing our proposal to list
the lesser prairie-chicken.
We will consider all comments and information we receive during the
comment period on this proposed rule during preparation of a final
rulemaking. Accordingly, the final decision may differ from this
proposal.
Public Hearings
Four public hearings have been scheduled on this proposal (see in
formation in DATES and ADDRESSES sections above). Persons needing
reasonable accommodations to attend and participate in a public hearing
should contact the Oklahoma Ecological Services Field Office at 918-
581-7458, as soon as possible. To allow sufficient time to process
requests, please call no later than 1 week before the hearing date.
Information regarding this proposed rule is available in alternative
formats upon request.
Clarity of the Rule
We are required by Executive Orders 12866 and 12988 and by the
Presidential Memorandum of June 1, 1998, to write all rules in plain
language. This means that each rule we publish must:
(a) Be logically organized;
(b) Use the active voice to address readers directly;
(c) Use clear language rather than jargon;
(d) Be divided into short sections and sentences; and
(e) Use lists and tables wherever possible.
If you feel that we have not met these requirements, send us
comments by one of the methods listed in the ADDRESSES section. To
better help us revise the rule, your comments should be as specific as
possible. For example, you should tell us the numbers of the sections
or paragraphs that are unclearly written, which sections or sentences
are too long, the sections where you feel lists or tables would be
useful, etc.
Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.)
This rule does not contain any new collections of information that
require approval by Office of Management and Budget under the Paperwork
Reduction Act. This rule will not impose recordkeeping or reporting
requirements on State or local governments, individuals, businesses, or
organizations. An agency may not conduct or sponsor, and a person is
not required to respond to, a collection of information unless it
displays a currently valid Office of Management and Budget control
number.
National Environmental Policy Act
We have determined that environmental assessments and environmental
impact statements, as defined under the authority of the National
Environmental Policy Act of 1969 (42 U.S.C. 4321 et seq.), need not be
prepared in connection with regulations adopted under section 4(a)(1)
of the Act. We published a notice outlining our reasons for this
determination in the Federal Register on October 25, 1983 (48 FR
49244).
Government-to-Government Relationship With Tribes
In accordance with the President's memorandum of April 29, 1994
(Government-to-Government Relations with Native American Tribal
Governments; 59 FR 22951), Executive Order 13175 (Consultation and
Coordination with Indian Tribal Governments), and the Department of the
Interior's manual at 512 DM 2, we readily acknowledge our
responsibility to communicate meaningfully with recognized Federal
Tribes on a government-to-government basis. In accordance with
Secretarial Order 3206 of June 5, 1997 (American Indian Tribal Rights,
Federal-Tribal Trust Responsibilities, and the Endangered Species Act),
we readily acknowledge our responsibilities to work directly with
tribes in developing programs for healthy ecosystems, to acknowledge
that tribal lands are not subject to the same controls as Federal
public lands, to remain sensitive to Indian culture, and to make
information available to tribes.
By letter dated April 19, 2011, we contacted known tribal
governments throughout the historical range of the lesser prairie-
chicken. We sought their input on our development of a proposed rule to
list the lesser prairie-chicken and encouraged them to contact the
Oklahoma Field Office if any portion of our request was unclear or to
request additional information. We did not receive any comments
regarding this request.
References Cited
A complete list of all references cited in this proposed rule is
available on the internet at http://www.regulations.gov, or upon
request from the Field Supervisor, Oklahoma Ecological Services Field
Office (see FOR FURTHER INFORMATION CONTACT section).
Authors
The primary authors of this proposed rule are the staff members of
the Oklahoma Ecological Services Field Office (see FOR FURTHER
INFORMATION CONTACT).
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, Transportation.
Proposed Regulation Promulgation
Accordingly, we propose to amend part 17, subchapter B of chapter
I, title 50 of the Code of Federal Regulations, as set forth below:
PART 17--[AMENDED]
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C.
4201-4245; Public Law 99-625, 100 Stat. 3500; unless otherwise
noted.
2. Amend Sec. 17.11(h) by adding an entry for ``Prairie-chicken,
lesser'' in alphabetical order under BIRDS to the List of Endangered
and Threatened Wildlife to read as follows:
[[Page 73888]]
Sec. 17.11 Endangered and threatened wildlife.
* * * * *
(h) * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species Vertebrate
-------------------------------------------------------- population where When Critical Special
Historic range endangered or Status listed habitat rules
Common name Scientific name threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
Birds
* * * * * * *
Prairie-chicken, lesser.......... (Tympanuchus U.S.A. (CO, KS, NM, Entire............. T ........... NA NA
pallidicinctus). OK, TX).
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * *
Dated: November 26, 2012.
Daniel M. Ashe,
Director, Fish and Wildlife Service.
[FR Doc. 2012-29331 Filed 12-10-12; 8:45 am]
BILLING CODE 4310-55-P