`[Federal Register Volume 86, Number 103 (Tuesday, June 1, 2021)]
[Proposed Rules]
[Pages 29432-29482]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-11442]



[[Page 29431]]

Vol. 86

Tuesday,

No. 103

June 1, 2021

Part III





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; Lesser Prairie-Chicken; 
Threatened Status With Section 4(d) Rule for the Northern Distinct 
Population Segment and Endangered Status for the Southern Distinct 
Population Segment; Proposed Rule

  Federal Register / Vol. 86 , No. 103 / Tuesday, June 1, 2021 / 
Proposed Rules  

[[Page 29432]]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R2-ES-2021-0015; FF09E21000 FXES11110900000 212]
RIN 1018-BB27


Endangered and Threatened Wildlife and Plants; Lesser Prairie-
Chicken; Threatened Status With Section 4(d) Rule for the Northern 
Distinct Population Segment and Endangered Status for the Southern 
Distinct Population Segment

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to 
list two Distinct Population Segments (DPSs) of the lesser prairie-
chicken (Tympanuchus pallidicinctus), a grassland bird known from 
southeastern Colorado, western Kansas, eastern New Mexico, western 
Oklahoma, and the Texas Panhandle under the Endangered Species Act of 
1973, as amended (Act). This determination also serves as our 12-month 
finding on a petition to list the lesser prairie-chicken. After a 
review of the best available scientific and commercial information, we 
find that listing the Southern DPS as endangered is warranted, and that 
listing the Northern DPS as threatened is warranted. Accordingly, we 
propose to list the Southern DPS as an endangered species under the Act 
and the Northern DPS as a threatened species with a rule issued under 
section 4(d) of the Act (``4(d) rule''). If we finalize this rule as 
proposed, it will add these two DPSs to the List of Endangered and 
Threatened Wildlife and extend the Act's protections to them. We also 
are notifying the public that we have scheduled informational meetings 
followed by public hearings on the proposed rule.

DATES: We will accept comments received or postmarked on or before 
August 2, 2021. Comments submitted electronically using the Federal 
eRulemaking Portal (see ADDRESSES, below) must be received by 11:59 
p.m. Eastern Time on the closing date. We must receive requests for a 
public hearing, in writing, at the address shown in FOR FURTHER 
INFORMATION CONTACT by July 16, 2021.
    Public informational meeting and public hearing: We will hold a 
public informational session from 5 p.m. to 6 p.m., Central Time, 
followed by a public hearing from 6:30 p.m. to 8:30 p.m., Central Time, 
on July 8, 2021. We will hold a second public informational session 
from 5 p.m. to 6 p.m., Central Time, followed by a public hearing from 
6:30 p.m. to 8:30 p.m., Central Time, on July 14, 2021.

ADDRESSES: You may submit comments by one of the following methods:
    (1) Electronically: Go to the Federal eRulemaking Portal: http://www.regulations.gov. In the Search box, enter FWS-R2-ES-2021-0015, 
which is the docket number for this rulemaking. Then, click on the 
Search button. On the resulting page, in the Search panel on the left 
side of the screen, under the Document Type heading, check the Proposed 
Rule box to locate this document. You may submit a comment by clicking 
on ``Comment Now!''
    (2) By hard copy: Submit by U.S. mail to: Public Comments 
Processing, Attn: FWS-R2-ES-2021-0015, U.S. Fish and Wildlife Service, 
MS: PRB/3W, 5275 Leesburg Pike, Falls Church, VA 22041-3803.
    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 Information Requested, below, for more information).
    Public informational meeting and public hearing: The public 
informational meetings and the public hearings will be held virtually 
using the Zoom platform. See Public Hearing, below, for more 
information.

FOR FURTHER INFORMATION CONTACT: Debra Bills, Field Supervisor, 
Arlington Ecological Services Field Office, 2005 NE Green Oaks Blvd., 
Suite 140, Arlington, TX 76006; telephone 817-277-1129. Persons who use 
a telecommunications device for the deaf (TDD) may call the Federal 
Relay Service at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Executive Summary

    Why we need to publish a rule. Under the Act, if we determine that 
a species is an endangered or threatened species throughout all or a 
significant portion of its range, we are required to promptly publish a 
proposal in the Federal Register and make a determination on our 
proposal within 1 year. To the maximum extent prudent and determinable, 
we must designate critical habitat for any species that we determine to 
be an endangered or threatened species under the Act. Listing a species 
as an endangered or threatened species and designation of critical 
habitat can only be completed by issuing a rule.
    What this document does. We propose the listing of the Northern DPS 
of the lesser prairie-chicken as a threatened species with a rule under 
section 4(d) of the Act and the Southern DPS of the lesser prairie-
chicken as an endangered species under the Act.
    The basis for our action. Under the Act, we may determine that a 
species is an endangered or threatened species because of 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. We make these determinations solely on the basis 
of the best scientific and commercial data available after conducting a 
review of the status of the species and after taking into account those 
efforts being made to protect the species.
    We have determined that both the northern and southern parts of the 
lesser prairie-chicken's range are discrete and significant under our 
DPS Policy and are, therefore, listable entities under the Act. The 
Southern DPS consists of the Shinnery Oak Ecoregion in New Mexico and 
Texas, and the Northern DPS consists of the Sand Sagebrush Ecoregion, 
the Mixed Grass Ecoregion, and the Short Grass/Conservation Reserve 
Program (CRP) Ecoregion in Texas, Oklahoma, Colorado, and Kansas. These 
two DPSs together encompass the entirety of the lesser prairie-
chicken's range. The primary threat impacting both DPSs is the ongoing 
loss of large, connected blocks of grassland and shrubland habitat. The 
Southern DPS has low resiliency, redundancy, and representation and is 
particularly vulnerable to severe droughts due to being located in the 
dryer and hotter southwestern portion of the range. Because the 
Southern DPS is currently at risk of extinction, we propose to list it 
as endangered.
    In the Northern DPS, as a result of habitat loss and fragmentation, 
resiliency has been much reduced across two of the ecoregions in the 
Northern DPS when compared to historical conditions. However, this DPS 
still has redundancy across the three ecoregions and genetic and 
environmental representation. We expect habitat loss and fragmentation 
across the Northern DPS to continue into the foreseeable future, 
resulting in even further reduced resiliency. Because

[[Page 29433]]

the Northern DPS is at risk of extinction in the foreseeable future, we 
propose to list it as threatened.
    Peer review. In accordance with our joint policy on peer review 
published in the Federal Register on July 1, 1994 (59 FR 34270), and 
our August 22, 2016, memorandum updating and clarifying the role of 
peer review of listing actions under the Act, we sought the expert 
opinions of 6 appropriate specialists regarding the species status 
assessment (SSA) report. We received responses from 4 specialists, 
which informed the proposed listing rule. The purpose of peer review is 
to ensure that our listing determinations and 4(d) rules are based on 
scientifically sound data, assumptions, and analyses. The peer 
reviewers have expertise in the biology, habitat, and threats to the 
species.

Information Requested

    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 governmental agencies, Native 
American Tribes, the scientific community, industry, or any other 
interested parties concerning this proposed rule.
    We particularly seek comments concerning:
    (1) The species' biology, range, and population trends, including:
    (a) Biological or ecological requirements of the species, including 
habitat requirements for feeding, breeding, and sheltering;
    (b) Genetics and taxonomy;
    (c) Historical and current range, including distribution patterns;
    (d) Historical and current population levels, and current and 
projected trends; and
    (e) Past and ongoing conservation measures for the species, its 
habitat, or both.
    (2) Factors that may affect the continued existence of the species, 
which may include habitat modification or destruction, overutilization, 
disease, predation, the adequacy of existing regulatory mechanisms, or 
other natural or manmade factors.
    (3) Biological, commercial trade, or other relevant data concerning 
any threats (or lack thereof) to this species and existing conservation 
measures and regulations that may be addressing those threats.
    (4) Additional information concerning the historical and current 
status, range, distribution, and population size of this species, 
including the locations of any additional populations of this species.
    (5) Information on regulations that are necessary and advisable to 
provide for the conservation of the Northern DPS of the lesser prairie-
chicken and that the Service can consider in developing a 4(d) rule for 
the DPS. In particular, information concerning the extent to which we 
should include any of the prohibitions associated with section 9 in the 
4(d) rule or whether any other forms of take should be excepted from 
the prohibitions in the 4(d) rule.
    (6) Information on whether an exception from the prohibitions 
associated with section 9 should be included in the 4(d) rule for the 
Northern DPS for industry and/or landowner participants who are 
enrolled in and operating in compliance with the mitigation framework 
included in the Range-Wide Conservation Plan for the Lesser Prairie-
Chicken being administered by the Western Association of Fish and 
Wildlife Agencies but who do not have incidental take coverage via the 
companion Candidate Conservation Agreement with Assurances covering oil 
and gas activities.
    (7) 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 in the future, 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.
    (8) Specific information on:
    (a) The amount and distribution of habitat for the lesser prairie-
chicken which should be considered for proposed critical habitat;
    (b) What may constitute ``physical or biological features essential 
to the conservation of the species within the geographical range 
currently occupied by the species'';
    (c) Where these features are currently found;
    (d) Whether any of these features may require special management 
considerations or practices;
    (e) What areas are currently occupied and contain features 
essential to the conservation of the species should be included in the 
designation and why; and
    (f) What unoccupied areas are essential for the conservation of the 
species and why. Please include sufficient information with your 
submission (such as scientific journal articles or other publications) 
to allow us to verify any scientific or commercial information you 
include.
    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 a 
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 ADDRESSES. We request that you 
send comments only by the methods described in ADDRESSES.
    If you submit information via http://www.regulations.gov, your 
entire submission--including any personal identifying information--will 
be posted on the website. 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 submissions on http://www.regulations.gov.
    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.
    Because we will consider all comments and information we receive 
during the comment period, our final determinations may differ from 
this proposal. Based on the new information we receive (and any 
comments on that new information), we may conclude that the Southern 
DPS is threatened instead of endangered, or that the Northern DPS is 
endangered instead of threatened, or we may conclude that either DPS 
does not warrant listing as either an endangered species or a 
threatened species. In addition, we may change the parameters of the 
prohibitions or the exceptions to those prohibitions in the 4(d) rule 
for the Northern DPS if we conclude it is appropriate in light of 
comments and new information received. For example, we may expand the 
incidental-take prohibitions or the exceptions to those prohibitions in 
the 4(d) rule for the Northern DPS to include prohibiting additional 
activities if we conclude that those additional activities are not 
compatible with conservation of the species. Conversely, we may 
establish additional exceptions to the incidental-take prohibitions in 
the final rule if we conclude that the activities would facilitate or 
are compatible with the conservation and recovery of the species.

[[Page 29434]]

List of Acronyms

    We use many acronyms in this proposed rule. For the convenience of 
the reader, we define some of them here:

ACEC = Area of Critical Environmental Concern
BLM = Bureau of Land Management
CI = confidence interval
CCAA = candidate conservation agreement with assurances
CCA/A = candidate conservation agreement and candidate conservation 
agreement with assurances
CPW = Colorado Parks and Wildlife
CRP = Conservation Reserve Program
DPS = Distinct Population Segment
KDWPT = Kansas Department of Wildlife, Parks and Tourism
LPCI = Lesser Prairie-Chicken Initiative
LPN = Listing Priority Number
NRCS = Natural Resources Conservation Service
ODWC = Oklahoma Department of Wildlife Conservation
PFW = the Service's Partners for Fish and Wildlife Program
RMPA = Resource Management Plan Amendment
RWP = Lesser Prairie-Chicken Range-wide Conservation Plan
SSA = Species Status Assessment
TPWD = Texas Parks and Wildlife Department
USFS = U.S. Forest Service
WAFWA = Western Association of Fish and Wildlife Agencies

Previous Federal Actions

    In 1973, the Service's Office of Endangered Species published a 
list of threatened wildlife of the United States in Resource 
Publication 114, often referred to as the ``Red Book.'' While this 
publication did not, by itself, provide any special protections, it 
served in part to solicit additional information regarding the status 
of the identified taxa. The lesser prairie-chicken was one of 70 birds 
included in this publication (Service 1973, pp. 134-135), but little 
Federal regulatory action occurred on the lesser prairie-chicken until 
1995.
    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 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. 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. This 12-month 
finding identified the lesser prairie-chicken as a candidate for 
listing with a listing priority number (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 FR 
24876); May 11, 2005 (70 FR 24870); September 12, 2006 (71 FR 53756); 
and December 6, 2007 (72 FR 69034) 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 
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.
    After making our 12-month finding in 1998, we received several 60-
day notices of intent to sue from WildEarth Guardians (formerly Forest 
Guardians) and several other parties for failure to make expeditious 
progress toward listing of the lesser prairie-chicken. WildEarth 
Guardians subsequently filed suit on September 1, 2010, in the U.S. 
District Court for the District of Colorado.
    In 2011, the Service entered into a settlement agreement with 
WildEarth Guardians that impacted multiple cases nationwide (In re 
Endangered Species Act Section 4 Deadline Litigation, No. 10-377 (EGS), 
MDL Docket No. 2165 (D.D.C. May 10, 2011)). As relevant to the lesser 
prairie-chicken, the agreement required the Service to submit a 
proposed listing rule for the lesser prairie-chicken to the Federal 
Register for publication by September 30, 2012.
    On September 27, 2012, the settlement agreement was modified to 
require that the proposed listing rule be submitted to the Federal 
Register on or before November 29, 2012. On December 11, 2012, we 
published a proposed rule (77 FR 73828) to list the lesser prairie-
chicken as a threatened species under the Act (16 U.S.C. 1531 et seq.). 
On May 6, 2013, we announced the publication of a proposed 4(d) rule 
under the authority of section 4(d) of the Act (78 FR 26302).
    On July 9, 2013, we announced a 6-month extension (78 FR 41022) of 
the final listing determination based on our finding that there was 
substantial disagreement regarding the sufficiency or accuracy of the 
available data relevant to our determination regarding the proposed 
listing rule.
    On April 10, 2014, we published a final rule listing the lesser 
prairie-chicken as a threatened species under the Act (79 FR 19973) and 
concurrently published a final 4(d) rule for the lesser prairie-chicken 
(79 FR 20073). However, on September 1, 2015, the final listing rule 
for the lesser prairie-chicken was vacated by the United States 
District Court for the Western District of Texas, which also mooted the 
final 4(d) rule. On July 20, 2016, the Service published in the Federal 
Register a final rule that removed the lesser prairie-chicken from the 
List of Endangered and Threatened Wildlife in accordance with the court 
decision (81 FR 47047).
    On September 8, 2016, we received a new petition from WildEarth 
Guardians, Defenders of Wildlife, and Center for Biological Diversity 
to list the lesser prairie-chicken as endangered throughout its entire 
range or in three distinct population segments (Molvar 2016, entire). 
On November 30, 2016, we published a 90-day petition finding that 
concluded that the petition to list the lesser prairie-chicken provided 
substantial information that the petitioned action may be warranted (81 
FR 86315). On June 12, 2019, the petitioners filed their complaint with 
the court alleging the Service failed to complete the 12-month petition 
finding for the lesser prairie-chicken. On September 12, 2019, the 
Service and the plaintiffs entered into a stipulated settlement 
agreement that the Service would submit a 12-month petition finding to 
the Federal Register no later than May 26, 2021. This 12-month finding 
completes the Service's obligations under that settlement agreement.

[[Page 29435]]

Supporting Documents

    An SSA team prepared an SSA report for the lesser prairie-chicken. 
The SSA team was composed of Service biologists, in consultation with 
other species experts. The SSA report represents a compilation of the 
best scientific and commercial data available concerning the status of 
the species, including the impacts of past, present, and future factors 
(both negative and beneficial) affecting the species. The Service sent 
the SSA report to six independent peer reviewers and received four 
responses. The Service also sent the SSA report to the five State fish 
and wildlife agencies within the range of the lesser prairie-chicken 
(Colorado, Kansas, New Mexico, Oklahoma, and Texas) and the four 
primary Federal agencies with whom we work to deliver conservation 
actions that could benefit the lesser prairie-chicken: The Bureau of 
Land Management (BLM), the Natural Resources Conservation Service 
(NRCS), Farm Service Agency (FSA), and U.S. Forest Service (USFS). 
These partners include scientists with expertise in management of 
either the lesser prairie-chicken or the habitat upon which the lesser 
prairie-chicken depends. We received responses from USFS, BLM, and all 
five of the State wildlife agencies. Comments and feedback from 
partners and peer reviewers were incorporated into the SSA report as 
appropriate and have informed this proposed rule.

I. Proposed Listing Determination

Background

    Below is a summary of the taxonomy, life history, and ecology of 
the lesser prairie-chicken; for a thorough review, please see the SSA 
report (version 2.2; Service 2021, pp. 5-14).
    The lesser prairie-chicken is in the order Galliformes, family 
Phasianidae, subfamily Tetraoninae; it is generally recognized as a 
species separate from the greater prairie-chicken (Tympanuchus cupido 
pinnatus) (Jones 1964, pp. 65-73; American Ornithologist's Union 1998, 
p. 122).
    Most lesser prairie-chicken adults live for 2 to 3 years and 
reproduce in the spring and summer (Service 2021, pp. 10-12). Males 
congregate on leks during the spring to attract and mate with females 
(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). Male prairie-chickens tend to exhibit strong breeding site 
fidelity, often returning to a specific lek many times, even in cases 
of declining female attendance and habitat condition (Copelin 1963, pp. 
29-30; Hoffman 1963, p. 731; Campbell 1972, pp. 698-699, Hagen et al. 
2005, entire, Harju et al. 2010, entire). Females tend to establish 
nests relatively close to the lek, commonly within 0.6 to 2.4 mi (1 to 
4 km) (Copelin 1963, p. 44; Giesen 1994, p. 97), where they incubate 8 
to 14 eggs for 24 to 27 days and then raise broods of young throughout 
the summer (Boal and Haukos 2016, p. 4). Some females will attempt a 
second nesting if the first nest fails (Johnsgard 1973, pp. 63-64; 
Merchant 1982, p. 43; Pitman et al. 2006, p. 25). Eggs and young lesser 
prairie-chickens are susceptible to natural mortality from 
environmental stress and predation. The appropriate vegetative 
community and structure is vital to provide cover for nests and young 
and to provide food resources as broods mature into adults (Suminski 
1977, p. 32; Riley 1978, p. 36; Riley et al. 1992, p. 386; Giesen 1998, 
p. 9). For more detail on habitat needs of the lesser prairie-chicken, 
please see the SSA report (Service 2021, pp. 9-14).
    The lesser prairie-chicken once ranged across the Southern Great 
Plains of Southeastern Colorado, Southwestern Kansas, Western Oklahoma, 
the Panhandle and South Plains of Texas, and Eastern New Mexico; 
currently, it occupies a substantially reduced portion of its presumed 
historical range (Rodgers 2016, p. 15). Estimates of the potential 
maximum historical range of the lesser prairie-chicken (e.g., Taylor 
and Guthery 1980a, p. 1, based on Aldrich 1963, p. 537; Johnsgard 2002, 
p. 32; Playa Lakes Joint Venture 2007, p. 1) range from about 64-115 
million acres (ac) (26-47 million hectares (ha)). The more recent 
estimate of the historical range of the lesser prairie-chicken 
encompasses an area of approximately 115 million ac (47 million ha). 
Presumably, not all of the area within this historical range was evenly 
occupied by lesser prairie-chicken, and some of the area may not have 
been suitable to regularly support lesser prairie-chicken populations 
(Boal and Haukos 2016, p. 6). However, the current range of the lesser 
prairie-chicken has been significantly reduced from the historical 
range at the time of European settlement. Estimates as to extent of the 
loss vary from greater than 90 percent reduction (Hagen and Giesen 
2005, unpaginated) to approximately 83 percent reduction (Van Pelt et 
al. 2013, p. 3).
    Lesser prairie-chicken monitoring has been occurring for multiple 
decades and have included multiple different methodologies. Estimates 
of population abundance prior to the 1960s are indeterminable and rely 
almost entirely on anecdotal information (Boal and Haukos 2016, p. 6). 
While little is known about precise historical population sizes, the 
lesser prairie-chicken was reported to be quite common throughout its 
range in the early 20th 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). For example, 
prior to 1900, as many as two million birds may have existed in Texas 
alone (Litton 1978, p. 1). Information regarding population size is 
available starting in the 1960s when the State fish and wildlife 
agencies began routine lesser prairie-chicken monitoring efforts. 
However, survey methodology and effort have differed over the decades, 
making it difficult to precisely estimate trends.
    The SSA report and this proposed rule rely on two main population 
estimates. The two methodologies largely cover different time periods, 
so we report the results of both throughout this proposed rule in order 
to give the best possible understanding of lesser prairie-chicken 
trends both recently and throughout the past decades.
    The first of the two studies used historical lek surveys and 
population reconstruction methods to calculate historical trends and 
estimate male abundance from 1965 through 2016 (Hagen et al. 2017, pp. 
6-9). We have identified concerns in the past with some of the 
methodologies and assumptions made in this analysis, and others have 
also noted the challenges of using these data for long-term trends (for 
example, Zavaleta and Haukos 2013, p. 545; Cummings et al. 2017, pp. 
29-30). While these concerns remain, including the very low sample 
sizes particularly in the 1960s, this work represents the only attempt 
to compile the extensive historical ground lek count data collected by 
State agencies to estimate the number of males at both the range-wide 
and ecoregional scales, and represents the best available data for 
understanding historical population trends.
    Following development of aerial survey methods (McRoberts et al. 
2011b, entire), the second summary of lesser prairie-chicken population 
data uses more statistically rigorous estimates of lesser prairie-
chicken abundance (both males and females). This second study uses data 
from aerial line-transect surveys throughout the range of the lesser 
prairie-chicken; these results are then extrapolated from the surveyed 
area to the rest of the range (Nasman et al. 2020, entire). The results 
of these

[[Page 29436]]

survey efforts should not be taken as precise estimates of the annual 
lesser prairie-chicken abundance, as indicated by the large confidence 
intervals. Thus, we caution the reader not to draw conclusions based 
upon annual fluctuations. Instead, we consider the best use of this 
data is for long-term trend analysis. Thus, in the SSA Report and this 
proposed rule, we report the population estimate for the current 
condition as the average of the past 5 years of surveys.
    The results of the study using lek data (abundance of males) 
indicate that lesser prairie-chicken range-wide abundance (based on a 
minimum estimated number of male lesser prairie-chicken at leks) peaked 
from 1965-1970 at a mean estimate of about 175,000 males (Figure 1). 
The estimated mean population maintained levels of greater than 100,000 
males until 1989, after which they steadily declined to a low of 25,000 
males in 1997 (Garton et al. 2016, p. 68). The mean population 
estimates following 1997 peaked again at about 92,000 males in 2006, 
but subsequently declined to 34,440 males in 2012 (Figure 1).
    The aerial survey results from 2012 through 2020 (Figure 2) 
estimated the lesser prairie-chicken population abundance, averaged 
over the most recent 5 years of surveys (2015-2020, no surveys in 
2019), at 27,384 (90% confidence interval: 15,690, 59,981) (Nasman et 
al. 2020, p. 21; Table 3.3).
BILLING CODE 4333-15-P
[GRAPHIC] [TIFF OMITTED] TP01JN21.019

    The preferred habitat of the lesser prairie-chicken is mixed-grass 
prairies and shrublands, with the exception of the Short-Grass/CRP 
Ecoregion where shrubs play a lesser role. Lesser prairie-chickens 
appear to select areas having a shrub component dominated by sand 
sagebrush or sand shinnery oak when those areas are available 
(Donaldson 1969, pp. 56, 62; Taylor and Guthery 1980a, p. 6; Giesen 
1998, pp. 3-4). In the southern and central portions of the lesser 
prairie-chicken range, small shrubs, such as sand shinnery oak, have 
been reported to be important for summer shade (Copelin 1963, p. 37; 
Donaldson 1969, pp. 44-45, 62), winter protection, and as supplemental 
foods (Johnsgard 1979, p. 112), while in the Short-Grass/CRP Ecoregion, 
stands of grass that provide adequate vegetative structure likely serve 
the same roles. The absence of anthropogenic features as well as other 
vertical structures is important, as lesser prairie-chickens tend to 
avoid using areas with trees, vertical structures, and other 
disturbances in areas with otherwise adequate habitat conditions (Braun 
et al. 2002, pp. 11-13; Pruett et al. 2009, pp. 1256, 1258; Hovick et 
al. 2014a, p. 1685; Boggie et al. 2017, entire; Lautenbach 2017, pp. 
104-142; Plumb et al. 2019, entire).
    At the population scale, the most important requirement for the 
lesser prairie-chicken is having large, intact, ecologically diverse 
grasslands to complete their life history and maintain healthy 
populations (Fuhlendorf et al. 2017b, entire). Historically, these 
ecologically diverse grasslands and shrublands were maintained by the 
occurrence of wildfires (keeping woody vegetation restricted to 
drainages and rocky outcroppings) and by grazing by bison and other 
large ungulates. The lesser prairie-chicken is a species that is area-
sensitive; that is, it requires large, intact grasslands for functional 
self-sustaining populations (Giesen 1998, pp. 3-4; Bidwell et al. 2002, 
pp. 1-3; Hagen et al. 2004, pp. 71, 76-77; Haukos and Zavaleta 2016, p. 
107).
    The lesser prairie-chicken now occurs within four ecoregions 
(Figure 3); these ecoregions were originally delineated in 2012 as part 
of the aerial survey designed to monitor long-trends in lesser prairie-
chicken populations. Each ecoregion is associated with unique 
environmental conditions based on habitat and climatic variables and 
some genetic differentiation (Boal and Haukos 2016, p. 5; Oyler-McCance 
et al. 2016, p. 653). These four ecoregions are the Short-Grass 
Prairie/CRP Mosaic Ecoregion in Kansas; the Sand Sagebrush Prairie 
Ecoregion in Colorado, Kansas, and Oklahoma; the Mixed-Grass Prairie 
Ecoregion in Kansas, Texas, and Oklahoma; and the Sand Shinnery Oak 
Prairie Ecoregion of New Mexico and Texas.

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    The Shinnery Oak Ecoregion occupies portions of eastern New Mexico 
and the South Plains of Texas (McDonald et al. 2012, p. 2). It has a 
variable vegetation community that contains a mix of shrubs such as 
sand shinnery oak (Quercus havardii) and sand sagebrush (Artemisia 
filifolia) as well as mixed and tall grasses and forbs (Grisham et al. 
2016a, p. 317). The mean population estimate ranged between about 5,000 
to 12,000 males through 1980, increased to 20,000 males in the mid-
1980s and declined to ~1,000 males in 1997 (Hagen et al. 2017 pp. 6-9). 
The mean population estimate peaked again to ~15,000 males in 2006 and 
then declined again to fewer than 3,000 males in the mid-2010s. While 
population estimates for the Shinnery Oak Ecoregion have varied over 
recent years, the most recent surveys estimate a 5-year average 
population size of 3,077 birds (90% confidence intervals (CI): 170, 
8,237). Approximately 11 percent of all lesser prairie-chicken occur in 
this ecoregion (Service 2021, pp. 66-78). Lesser prairie-chicken from 
the Shinnery Oak Ecoregion are genetically distinct and geographically 
isolated from the other three ecoregions by 95 miles (mi) (153 
kilometers (km)) (Figure 3; Oyler-McCance et al. 2016, p. 653).
    With the exception of lesser prairie-chicken areas owned by the 
State Game Commission and federally owned BLM lands in New Mexico, the 
majority of the Shinnery Oak Ecoregion is privately owned (Grisham et 
al. 2016a, p. 315). Nearly all of the area in the Texas portion of the 
ecoregion is privately owned and managed for agricultural use and 
petroleum production (Haukos 2011, p. 110). The remaining patches of 
shinnery oak prairie have become isolated, relict communities because 
the surrounding grasslands have been

[[Page 29438]]

converted to row crop agriculture or fragmented by oil and gas 
exploration and urban development (Peterson and Boyd 1998, p. 22). 
Additionally, honey mesquite (Prosopis glandulosa) encroachment within 
this ecoregion has played a significant role in decreasing available 
space for the lesser prairie-chicken. Technological advances in 
irrigated row crop agriculture have led to more recent conversion of 
shinnery oak prairie habitat to row crops in Eastern New Mexico and 
West Texas (Grisham et al. 2016a, p. 316).
    The Sand Sagebrush Ecoregion occurs in Southeast Colorado, 
Southwest Kansas, and a small portion of Western Oklahoma (McDonald et 
al. 2012, p. 2). The vegetation community in this area primarily 
consists of sand sagebrush and the associated mixed and tall grass 
species that are usually found in the sandier soils adjacent to rivers, 
streams, and other drainages in the area. Lesser prairie-chicken from 
the Sand Sagebrush Ecoregion form a distinct genetic cluster from other 
ecoregions but have likely contributed some individuals to the Short-
Grass/CRP Ecoregion through dispersal (Oyler-McCance et al. 2016, p. 
653).
    Historically, the Sand Sagebrush Ecoregion supported the highest 
density of lesser prairie-chicken and was considered the core of the 
lesser prairie-chicken range (Haukos et al. 2016, p. 282). A single 
flock detected in Seward County, Kansas, was estimated to potentially 
contain more than 15,000 birds (Bent 1932, p. 281). The population size 
is estimated to have peaked at more than 85,000 males in the 1970s 
(Garton et al. 2016, p. 62) and has been in decline since the late 
1970s. More recent survey efforts estimate a 5-year average population 
size of 1,215 birds (90% CI: 196, 4,547). Less than 5 percent of all 
lesser prairie-chicken occur in this ecoregion (Service 2021, pp. 66-
78). Most of the decline has been attributed to habitat deterioration 
and conversion of sand sagebrush to intensive row crop agriculture due 
to an increase in center pivot irrigation (Jensen et al. 2000, p. 172). 
Environmental conditions in this ecoregion can be extreme, with 
stochastic events such as blizzards negatively impacting lesser 
prairie-chicken populations.
    The Short-Grass/CRP Ecoregion falls within the mixed- and short-
grass prairies of Central and Western Kansas (McDonald et al. 2012, p. 
2). As the name implies, much of this ecoregion historically consisted 
of short-grass prairie interspersed with mixed-grass prairie as well as 
sand sagebrush prairie along some drainages (Dahlgren et al. 2016, p. 
260). By the 1980s, large expanses of prairies had been converted from 
native grass for crop production in this ecoregion. After the 
introduction of the CRP in 1985, landowners began to have enhanced 
incentives to convert croplands to perennial grasslands to provide 
cover for the prevention of soil erosion. The State of Kansas required 
those enrolling in the CRP to plant native mixed- and tall-grass 
species, which is notable because the grasses in this area historically 
consisted largely of short-grass species, which generally do not 
provide adequate habitat for the lesser prairie-chicken. For more 
information on the CRP, see the SSA report (Service 2021, pp. 52-54).
    Prior to the late 1990s, lesser prairie-chickens in this ecoregion 
were thought to be largely absent (or occurred sporadically in low 
densities) (Hagen and Giesen 2005, unpaginated; Rodgers 1999, p. 19). 
We do not know what proportion of the eastern Short-Grass/CRP Ecoregion 
in Kansas was historically occupied by lesser prairie-chicken (Hagen 
2003, pp. 3-4), and surveys in this ecoregion only began in earnest in 
1999 (Dahlgren et al. 2016, p. 262). The CRP is an idle lands program, 
which requires establishment of grass cover and precludes tillage or 
agricultural commodity production for the duration of the contract, and 
has contractual limits to the type, frequency, and timing of management 
activities, such as burning, haying, or grazing of the established 
grasses. As a result of these factors, CRP often provides the 
vegetative structure preferentially used by lesser prairie-chickens for 
nesting. In the State of Kansas, the availability of CRP lands, 
especially CRP lands with interseeded or original seed mixture of 
forbs, resulted in increased habitat availability for the lesser 
prairie-chicken and, thus, an expansion of the known lesser prairie-
chicken range and an increase in the abundance of the lesser prairie-
chicken (Rodgers 1999, pp. 18-19; Fields 2004, pp. 11, 105; Fields et 
al. 2006, pp. 931, 937; Sullins et al. 2018, p. 1617).
    The Short-Grass/CRP Ecoregion is now estimated to contain the 
majority of lesser prairie-chickens compared to the other ecoregions, 
with recent survey efforts estimating a 5-year average population size 
of 16,957 birds (90% CI: 13,605, 35,350), representing approximately 62 
percent of the rangewide population (Service 2021, pp. 66-78). Recent 
genetic studies indicate that lesser prairie-chickens have moved 
northward largely from the Mixed-Grass Ecoregion and, to a lesser 
extent, the Sand Sagebrush Ecoregion into the Short-Grass/CRP Ecoregion 
(Oyler-McCance et al. 2016, p. 653).
    The northern section of this ecoregion is the only portion of the 
lesser prairie-chicken's range where co-occurrence with greater 
prairie-chicken occurs. Hybridization rates of up to 5 percent have 
been reported (Pitman 2013, p. 5), and that rate seemed to be stable 
across multiple years, though sampling is limited where the species co-
occur (Pitman 2013, p. 12). Limited additional work has been completed 
to further assess the rate of hybridization. There are concerns about 
the implications of genetic introgression (dilution) of lesser prairie-
chicken genes, particularly given that potential effects are poorly 
understood (Dahlgren et al. 2016, p. 276). Unresolved issues include 
whether hybridization reduces fitness, alters behavior or morphological 
traits in either a positive or negative way and the historical 
occurrence and rate of hybridization.
    The Mixed-Grass Ecoregion for the lesser prairie-chicken lies in 
the northeastern panhandle of Texas, the panhandle of northwestern 
Oklahoma, and south-central Kansas (McDonald et al. 2012, p. 2). The 
Mixed-Grass Ecoregion is separated from the Short-Grass/CRP Ecoregion 
in Kansas by the Arkansas River. The vegetation community in this 
ecoregion consists largely of a mix of perennial grasses and shrubs 
such as sand sagebrush, sand plum (Prunus angustifolia), yucca (Yucca 
spp.), and sand shinnery oak (Wolfe et al. 2016, p. 300). Based upon 
population reconstruction data, the mean population estimate was around 
30,000 males in the 1970s and 1980s followed by a decline in the 1990s 
(Hagen et al. 2016, pp. 6-7). The mean population estimate peaked again 
in the early 2000s at around 25,000 males, before declining to and 
remaining at its lowest levels, <10,000 males since 2012 (Hagen et al. 
2016, pp. 6-7). Although historical population estimates in the 
ecoregion reported some of the highest densities of lesser prairie-
chicken in the range (Wolfe et al. 2016, p. 299), recent aerial survey 
efforts estimate a 5-year average population size of 6,135 birds 
(including males and females; 90% CI: 1,719, 11,847). The recent survey 
work estimates about 22 percent of lesser prairie-chicken occur in this 
ecoregion (Service 2021, pp. 66-78). Lesser prairie-chicken from the 
Mixed-Grass Ecoregion are similar in genetic variation with the Short-
Grass/CRP Ecoregion, with individuals likely dispersing from the Mixed-
Grass Ecoregion to the Short-Grass/CRP Ecoregion (Oyler-McCance et al. 
2016, p. 653).

[[Page 29439]]

Distinct Population Segment Evaluation

    Under the Act, the term species includes ``any subspecies of fish 
or wildlife or plants, and any distinct population segment of any 
species of vertebrate fish or wildlife which interbreeds when mature.'' 
16 U.S.C. 1532(16). To guide the implementation of the distinct 
population segment (DPS) provisions of the Act, we and the National 
Marine Fisheries Service (National Oceanic and Atmospheric 
Administration--Fisheries), published the Policy Regarding the 
Recognition of Distinct Vertebrate Population Segments Under the 
Endangered Species Act (DPS Policy) in the Federal Register on February 
7, 1996 (61 FR 4722). Under our DPS Policy, we use two elements to 
assess whether a population segment under consideration for listing may 
be recognized as a DPS: (1) The population segment's discreteness from 
the remainder of the species to which it belongs, and (2) the 
significance of the population segment to the species to which it 
belongs. If we determine that a population segment being considered for 
listing is a DPS, then the population segment's conservation status is 
evaluated based on the five listing factors established by the Act to 
determine if listing it as either endangered or threatened is 
warranted.
    As described in Previous Federal Actions, we were petitioned to 
list the lesser prairie-chicken either rangewide or in three distinct 
population segments. The petition suggested three DPS configurations: 
(1) Shinnery Oak Ecoregion, (2) the Sand Sagebrush Ecoregion, and (3) a 
segment including the Mixed-Grass Ecoregion and the Short-Grass/CRP 
Ecoregion. The petition also combined the Sand Sagebrush Ecoregion, the 
Mixed-Grass Ecoregion, and the Short-Grass/CRP Ecoregion due to 
evidence they are linked genetically and geographically (Molver 2016, 
p. 18). Genetic studies indicate that lesser prairie-chicken from the 
Mixed-Grass Ecoregion are similar in genetic variation with the Short-
Grass/CRP Ecoregion, with individuals likely dispersing from the Mixed-
Grass Ecoregion to the Short-Grass/CRP Ecoregion (Oyler-McCance et al. 
2016, p. 653). Other genetic data indicate that lesser prairie-chicken 
from the Sand Sagebrush Ecoregion and lesser prairie-chicken from the 
Mixed-Grass and Short-Grass/CRP Ecoregion also share genetic traits. 
Genetic studies of neutral markers indicate that, although lesser 
prairie-chicken from the Sand Sagebrush Ecoregion form a distinct 
genetic cluster from other ecoregions, they have also likely 
contributed some individuals to the Short-Grass/CRP Ecoregion through 
dispersal (Oyler-McCance et al. 2016, p. 653). Additionally, these 
three ecoregions are not geographically isolated from one another 
(Figure 3). As a result of the shared genetic characteristics and the 
geographic connections, we have concluded the Sand Sagebrush Ecoregion, 
the Mixed-Grass Ecoregion, and the Short-Grass/CRP Ecoregion are 
appropriately considered as one potential DPS configuration.
    Under the Act, we have the authority to consider for listing any 
species, subspecies, or, for vertebrates, any distinct population 
segment (DPS) of these taxa if there is sufficient information to 
indicate that such action may be warranted. We considered whether two 
segments meet the DPS criteria under the Act: The southernmost 
ecoregion (Shinnery Oak) and a segment containing the three 
northernmost ecoregions (Mixed-Grass, Short-Grass/CRP, and Sand 
Sagebrush).
Discreteness
    Under our DPS Policy, a population segment of a vertebrate taxon 
may be considered discrete if it satisfies either of the following 
conditions: (1) It is markedly separated from other populations of the 
same taxon as a consequence of physical, physiological, ecological, or 
behavioral factors. Quantitative measures of genetic or morphological 
discontinuity may provide evidence of this separation; or (2) it is 
delimited by international governmental boundaries within which 
differences in control of exploitation, management of habitat, 
conservation status, or regulatory mechanisms exist that are 
significant in light of section 4(a)(1)(D) of the Act.
    We conclude the two segments satisfy the ``markedly separate'' 
conditions. The two groups of ecoregions are not separated from each 
other by international governmental boundaries. The southernmost 
ecoregion (Shinnery Oak) is separated from the three northern 
ecoregions by approximately 95 mi (153 km), much of which is developed 
or otherwise unsuitable habitat. There has been no recorded movement of 
lesser prairie-chickens between the Shinnery Oak Ecoregion and the 
three northern ecoregions over the past several decades. Because there 
is no connection between the two parts of the range, there is 
subsequently no gene flow between them (Oyler-McCance et al. 2016, 
entire).
    Therefore, we have determined that both the southern ecoregion and 
the northern three ecoregions of the lesser prairie-chicken range both 
individually meet the condition for discreteness under our DPS Policy.
Significance
    Under our DPS Policy, once we have determined that a population 
segment is discrete, we consider its biological and ecological 
significance to the larger taxon to which it belongs. This 
consideration may include, but is not limited to: (1) Evidence of the 
persistence of the discrete population segment in an ecological setting 
that is unusual or unique for the taxon, (2) evidence that loss of the 
population segment would result in a significant gap in the range of 
the taxon, (3) evidence that the population segment represents the only 
surviving natural occurrence of a taxon that may be more abundant 
elsewhere as an introduced population outside its historical range, or 
(4) evidence that the discrete population segment differs markedly from 
other populations of the species in its genetic characteristics.
    For the lesser prairie-chicken, we first considered evidence that 
the discrete population segment differs markedly from other populations 
of the species in its genetic characteristics. The most recent 
rangewide genetic study examined neutral markers in the four ecoregions 
where the lesser prairie-chicken occurs. It concluded that there is 
significant genetic variation across the lesser prairie-chicken range. 
The study also concluded that although there is genetic exchange 
between the three northern ecoregions (particularly movement of birds 
northward from the Mixed-Grass Ecoregion to the Short-Grass/CRP 
Ecoregion, and, to a lesser extent, from the Sand Sagebrush Ecoregion 
into the Short-Grass/CRP Ecoregion), lesser prairie-chicken from the 
Shinnery Oak Ecoregion in the southwestern part of the range are a 
group that is genetically distinct from the remainder of the range 
(Oyler-McCance et al. 2016, p. 653). The Shinnery Oak Ecoregion is more 
distinct from all three ecoregions in the Northern DPS than those 
ecoregions are from each other (Oyler-McCance et al. 2016, Table 4). 
The Shinnery Oak Ecoregion was likely historically connected to the 
remainder of the range, but the two parts have been separated since 
approximately the time of European settlement. Therefore, the two 
segments of the range are genetically distinct from each other.
    We next considered evidence that loss of the population segment 
would result in a significant gap in the range of the taxon. As 
discussed above, the southwestern and northeastern parts of the range 
are separated by

[[Page 29440]]

approximately 95 mi (153 km). The loss of the Shinnery Oak Ecoregion 
would result in the loss of the entire southwestern part of the 
species' range and decrease species redundancy and ecological and 
genetic representation, thus decreasing its ability to withstand 
demographic and environmental stochasticity. The loss of the other 
three ecoregions would result in the loss of 75 percent of the species' 
range, as well as loss of the part of the range (the Short-Grass/CRP 
Ecoregion) which has recently experienced a northward expansion of 
occupied habitat. This would create a large gap in the northeastern 
portion of the species range, also reducing the species' ability to 
withstand demographic and environmental stochasticity. Therefore, the 
loss of either part of the range would result in a significant gap in 
the range of the lesser prairie-chicken. These genetic differences and 
the evidence that a significant gap in the range of the taxon would 
result from the loss of either discrete population segment both 
individually satisfy the significance criterion of the DPS Policy. 
Therefore, under the Service's DPS Policy, we find that both the 
southern and northern segments of the lesser prairie-chicken are 
significant to the taxon as a whole.
Distinct Population Segment Conclusion
    Our DPS Policy directs us to evaluate the significance of a 
discrete population in the context of its biological and ecological 
significance to the remainder of the species to which it belongs. Based 
on an analysis of the best available scientific and commercial data, we 
conclude that the northern and southern parts of the lesser prairie-
chicken range are discrete due to geographic (physical) isolation from 
the remainder of the taxon. Furthermore, we conclude that both parts of 
the lesser prairie-chicken range are significant, because loss of 
either part would result in a significant gap in the range of the 
taxon, and because the two parts of the range are markedly separate 
based on neutral genetic markers. Therefore, we conclude that both the 
northern and southern parts of the lesser prairie-chicken range are 
both discrete and significant under our DPS Policy and are, therefore, 
uniquely listable entities under the Act.
    Based on our DPS Policy (61 FR 4722; February 7, 1996), if a 
population segment of a vertebrate species is both discrete and 
significant relative to the taxon as a whole (i.e., it is a distinct 
population segment), its evaluation for endangered or threatened status 
will be based on the Act's definition of those terms and a review of 
the factors enumerated in section 4(a) of the Act. Having found that 
both parts of the lesser prairie-chicken range meet the definition of a 
distinct population segment, we evaluate the status of both the 
Southern DPS and the Northern DPS of the lesser prairie-chicken to 
determine whether either meets the definition of an endangered or 
threatened species under the Act. The line demarcating the break 
between the Northern and Southern DPS lies approximately half-way 
between the two DPSs in the unoccupied area between them (Figure 4).
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[[Page 29442]]

Regulatory and Analytical Framework

Regulatory Framework
    Section 4 of the Act (16 U.S.C. 1533) and its implementing 
regulations (50 CFR part 424) set forth the procedures for determining 
whether a species is an endangered species or a threatened species. The 
Act defines an endangered species as a species that is ``in danger of 
extinction throughout all or a significant portion of its range,'' and 
a threatened species as a species that is ``likely to become an 
endangered species within the foreseeable future throughout all or a 
significant portion of its range.'' The Act requires that we determine 
whether any species is an ``endangered species'' or a ``threatened 
species'' because of any of the following 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.
    These factors represent broad categories of natural or human-caused 
actions or conditions that could have an effect on a species' continued 
existence. In evaluating these actions and conditions, we look for 
those that may have a negative effect on individuals of the species, as 
well as other actions or conditions that may ameliorate any negative 
effects or may have positive effects.
    We use the term ``threat'' to refer in general to actions or 
conditions that are known to or are reasonably likely to negatively 
affect individuals of a species. The term ``threat'' includes actions 
or conditions that have a direct impact on individuals (direct 
impacts), as well as those that affect individuals through alteration 
of their habitat or required resources (stressors). The term ``threat'' 
may encompass--either together or separately--the source of the action 
or condition or the action or condition itself.
    However, the mere identification of any threat(s) does not 
necessarily mean that the species meets the statutory definition of an 
``endangered species'' or a ``threatened species.'' In determining 
whether a species meets either definition, we must evaluate all 
identified threats by considering the expected response by the species 
and the effects of the threats--in light of those actions and 
conditions that will ameliorate the threats--on an individual, 
population, and species level. We evaluate each threat and its expected 
effects on the species, then analyze the cumulative effect of all of 
the threats on the species as a whole. We also consider the cumulative 
effect of the threats in light of those actions and conditions that 
will have positive effects on the species, such as any existing 
regulatory mechanisms or conservation efforts. The Secretary determines 
whether the species meets the definition of an ``endangered species'' 
or a ``threatened species'' only after conducting this cumulative 
analysis and describing the expected effect on the species now and in 
the foreseeable future.
    The Act does not define the term ``foreseeable future,'' which 
appears in the statutory definition of ``threatened species.'' Our 
implementing regulations at 50 CFR 424.11(d) set forth a framework for 
evaluating the foreseeable future on a case-by-case basis. The term 
``foreseeable future'' extends only so far into the future as the 
Services can reasonably determine that both the future threats and the 
species' responses to those threats are likely. In other words, the 
foreseeable future is the period of time in which we can make reliable 
predictions. ``Reliable'' does not mean ``certain''; it means 
sufficient to provide a reasonable degree of confidence in the 
prediction. Thus, a prediction is reliable if it is reasonable to 
depend on it when making decisions.
    It is not always possible or necessary to define foreseeable future 
as a particular number of years. Analysis of the foreseeable future 
uses the best scientific and commercial data available and should 
consider the timeframes applicable to the relevant threats and to the 
species' likely responses to those threats in view of its life-history 
characteristics. Data that are typically relevant to assessing the 
species' biological response include species-specific factors such as 
lifespan, reproductive rates or productivity, certain behaviors, and 
other demographic factors.
Analytical Framework
    The SSA report documents the results of our comprehensive 
biological review of the best scientific and commercial data regarding 
the status of the species, including an assessment of the potential 
threats to the species. The SSA report does not represent a decision by 
the Service on whether the species should be proposed for listing as an 
endangered or threatened species under the Act. It does, however, 
provide the scientific basis that informs our regulatory decisions, 
which involve the further application of standards within the Act and 
its implementing regulations and policies. The following is a summary 
of the key results and conclusions from the SSA report; the full SSA 
report can be found on http://www.regulations.gov at Docket FWS-R2-ES-
2021-0015.
    To assess lesser prairie-chicken viability, we used the three 
conservation biology principles of resiliency, redundancy, and 
representation (Shaffer and Stein 2000, pp. 306-310). Briefly, 
resiliency supports the ability of the species to withstand 
environmental and demographic stochasticity (for example, wet or dry, 
warm or cold years), redundancy supports the ability of the species to 
withstand catastrophic events (for example, droughts, large pollution 
events), and representation supports the ability of the species to 
adapt over time to long-term changes in the environment (for example, 
climate changes). In general, the more resilient and redundant a 
species is and the more representation it has, the more likely it is to 
sustain populations over time, even under changing environmental 
conditions. Using these principles, we identified the species' 
ecological requirements for survival and reproduction at the 
individual, population, and species levels, and described the 
beneficial and risk factors influencing the species' viability.
    The SSA process can be categorized into three sequential stages. 
During the first stage, we evaluated the individual species' life-
history needs. The next stage involved an assessment of the historical 
and current condition of the species' demographics and habitat 
characteristics, including an explanation of how the species arrived at 
its current condition. The final stage of the SSA involved making 
predictions about the species' responses to positive and negative 
environmental and anthropogenic influences that are likely to occur in 
the future. Throughout all of these stages, we used the best available 
information to characterize viability as the ability of a species to 
sustain populations in the wild over time. We use this information to 
inform our regulatory decision.
    The SSA report does not assess the distinct population segments 
proposed for the species because the SSA focuses on the biological 
factors, rather than those, such as DPS, that are created by the 
regulatory framework of the Act. Both the geospatial and threats 
analysis in the SSA report are summarized by ecoregion. In this 
proposed rule, we present the analyses per ecoregion from the SSA 
report but also summarize per DPS as applicable.

[[Page 29443]]

Summary of Biological Status and Threats

    In this discussion, we review the biological condition of the 
species and its resources, and the threats that influence the species' 
current and future condition, in order to assess the species' overall 
viability and the risks to that viability.
    We note that, by using the SSA framework to guide our analysis of 
the scientific information documented in the SSA report, we have not 
only analyzed individual effects on the species, but we have also 
analyzed their potential cumulative effects. We incorporate the 
cumulative effects into our SSA analysis when we characterize the 
current and future condition of the species. To assess the current and 
future condition of the species, we undertake an iterative analysis 
that encompasses and incorporates the threats individually and then 
accumulates and evaluates the effects of all the factors that may be 
influencing the species, including threats and conservation efforts. 
Because the SSA framework considers not just the presence of the 
factors, but to what degree they collectively influence risk to the 
entire species, our assessment integrates the cumulative effects of the 
factors and replaces a standalone cumulative effects analysis.
Representation
    To evaluate representation as a component of lesser prairie-chicken 
viability, we considered the need for multiple healthy lesser prairie-
chicken populations within each of the four ecoregions to conserve the 
genetic and ecological diversity of the lesser prairie-chicken. Each of 
the four ecoregions varies in terms of vegetative communities and 
environmental conditions, resulting in differences in abundance and 
distribution and management strategies (Boal and Haukos 2016, p. 5). 
Despite reduced range and population size, most lesser prairie-chicken 
populations appear to have maintained comparatively high levels of 
neutral genetic variation (DeYoung and Williford 2016, p. 86). As 
discussed in Significance above, recent genetic studies also show 
significant genetic variation across the lesser prairie-chicken range 
based on neutral markers (Service 2021, Figure 2.4), which supports 
management separation of these four ecoregions and highlights important 
genetic differences between them (Oyler-McCance et al. 2016, p. 653). 
While it is unknown how this genetic variation relates to differences 
in adaptive capacity between the ecoregions, maintaining healthy lesser 
prairie-chicken populations across this range of diversity increases 
the likelihood of conserving inherent ecological and genetic variation 
within the species to enhance its ability for adaptation to future 
changes in environmental conditions.
Resiliency
    In the case of the lesser prairie-chicken, we considered the 
primary indicators of resiliency to be habitat availability, population 
abundance, growth rates, and quasi-extinction risk. Lesser prairie-
chicken populations within ecoregions must have sufficient habitat and 
population growth potential to recover from natural disturbance events 
such as extensive wildfires, extreme hot or cold events, extreme 
precipitation events, or extended local periods of below-average 
rainfall. These events can be particularly devastating to populations 
when they occur during the late spring or summer when nesting and brood 
rearing are occurring and individuals are more susceptible to 
mortality.
    The lesser prairie-chicken is considered a ``boom-bust'' species 
based on its high reproductive potential with a high degree of annual 
variation in rates of successful reproduction and recruitment. These 
variations are largely driven by the influence of seasonal 
precipitation patterns (Grisham et al. 2013, pp. 6-7), which impact the 
population through effects on the quality of habitat. Periods of below-
average precipitation and higher spring/summer temperatures result in 
less appropriate grassland vegetation cover and less food available, 
resulting in decreased reproductive output (bust periods). Periods with 
above-normal precipitation and cooler spring/summer temperatures will 
support favorable lesser prairie-chicken habitat conditions and result 
in high reproductive success (boom periods). In years with particularly 
poor weather conditions, individual female lesser prairie-chicken may 
forgo nesting for the year. This population characteristic highlights 
the need for habitat conditions to support large population growth 
events during favorable climatic conditions so they can withstand the 
declines during poor climatic conditions without a high risk of 
extirpation.
    Historically, the lesser prairie-chicken had large expanses of 
grassland habitat to maintain populations. Early European settlement 
and development of the Southern Great Plains for agriculture initially, 
and for energy extraction later, substantially reduced the amount and 
connectivity of the grasslands of this region. Additionally, if 
historically some parts of the range were drastically impacted or 
eliminated due to a stochastic event, that area could be reestablished 
from other populations. Today, those characteristics of the grasslands 
have been degraded, resulting in the loss and fragmentation of 
grasslands in the Southern Great Plains. Under present conditions, the 
potential lesser prairie-chicken habitat is limited to small, 
fragmented grassland patches (relative to historical conditions) 
(Service 2021, pp. 64-78). The larger and more intact the remaining 
grassland patches are, with appropriate vegetation structure, the 
larger, healthier, and more resilient the lesser prairie-chicken 
populations will be. Exactly how large habitat patches should be to 
support healthy populations depends on the quality and intactness of 
the patches. Recommended total space needed for persistence of lesser 
prairie-chicken populations ranges from a minimum of about 12,000 ac 
(4,900 ha) (Davis 2005, p. 3) up to more than 50,000 ac (20,000 ha) to 
support single leks, depending on the quality and intactness of the 
area (Applegate and Riley 1998, p. 14; Haufler et al. 2012, pp. 7-8; 
Haukos and Zavaleta 2016, p. 107).
    A single lesser prairie-chicken lek is not considered a population 
that can persist on its own. Instead, complexes of multiple leks that 
interact with each other are required for a lesser prairie-chicken 
population to be persistent over time. These metapopulation dynamics, 
in which individuals interact on the landscape to form larger 
populations, are dependent upon the specific biotic and abiotic 
landscape characteristics of the site and how those characteristics 
influence space use, movement, patch size, and fragmentation (DeYoung 
and Williford 2016, pp. 89-91). Maintaining multiple, highly resilient 
populations (complexes of leks) within the four ecoregions that have 
the ability to interact with each other will increase the probability 
of persistence in the face of environmental fluctuations and stochastic 
events. Because of this concept of metapopulations and their influence 
on long-term persistence, when evaluating lesser prairie-chicken 
populations, site-specific information can be informative. However, 
many of the factors affecting lesser prairie-chicken populations should 
be analyzed at larger spatial scales (Fuhlendorf et al. 2002, entire).
Redundancy
    Redundancy describes the ability of a species to withstand 
catastrophic events. Catastrophes are stochastic

[[Page 29444]]

events that are expected to lead to population collapse regardless of 
population health and for which adaptation is unlikely. Redundancy 
spreads the risk and can be measured through the duplication and 
distribution of resilient populations that are connected across the 
range of the species. The larger the number of highly resilient 
populations the lesser prairie-chicken has, distributed over a large 
area within each ecoregion, the better the species can withstand 
catastrophic events. Catastrophic events for lesser prairie-chicken 
might include extreme drought; widespread, extended droughts; or a 
disease outbreak.
    Measuring redundancy for lesser prairie-chicken is a difficult task 
due to the physiological and biological characteristics of the species, 
which make it difficult to survey and limit the usefulness of survey 
results. To estimate redundancy for the lesser prairie-chicken, we 
estimated the geographic distribution of predicted available habitat 
within each of the four ecoregions and the juxtaposition of that 
habitat to other habitat and non-habitat. As the amount of large 
grassland patches decreases and grassland patches become more isolated 
to reduce or preclude lesser prairie-chicken movement between them, the 
overall redundancy of the species is reduced. As redundancy decreases 
within any representative ecoregion or DPS, the likelihood of 
extirpation within that ecoregion increases. As large grassland 
patches, the connectivity of those patches, and the number of lesser 
prairie-chicken increase, so does the redundancy within an ecoregion or 
a DPS.
Current Condition
    In the SSA report, we assessed the current condition of the lesser 
prairie-chicken through an analysis of existing habitat; a review of 
factors that have impacted the species in the past, including a 
geospatial analysis to estimate areas of land cover impacts on the 
current landscape condition; a summary of the current potential usable 
area based upon our geospatial analysis; and a summary of past and 
current population estimates. We also evaluated and summarized the 
benefit of the extensive conservation efforts that are ongoing 
throughout the lesser prairie-chicken range to conserve the species and 
its habitat.
Geospatial Analysis Summary
    The primary concern for the lesser prairie-chicken is habitat loss 
and fragmentation. We conducted a geographic information system (GIS) 
analysis to analyze the extent of usable land cover changes and 
fragmentation within the range of the lesser prairie-chicken, 
characterizing landscape conditions spatially to analyze the ability of 
those landscapes to support the biological needs of the lesser prairie-
chicken. Impacts included in this analysis were the direct and indirect 
effects of areas that were converted to cropland; encroached by woody 
vegetation such as mesquite and eastern red cedar (Juniperus 
virginiana); and developed for roads, petroleum production, wind 
energy, and transmission lines. We acknowledge that there are other 
impacts, such as power lines or incompatible grazing on the landscape, 
that can affect lesser prairie-chicken habitat. For those impacts, 
either no geospatial data were available, or the available data would 
have added so much complexity to our geospatial model that the results 
would have been uninterpretable or not explanatory for our purpose.
    There are several important limitations to our geospatial analysis. 
First, it is a landscape-level analysis, so the results only represent 
broad trends at the ecoregional and rangewide scales. Secondly, this 
analysis does not incorporate different levels of habitat quality, as 
the data do not exist at the spatial scale or resolution needed. Our 
analysis only considers areas as either potentially usable or not 
usable by lesser prairie-chicken based upon land cover classifications. 
We recognize that some habitat, if managed as high-quality grassland, 
may have the ability to support higher densities of lesser prairie-
chicken than other habitat that exists at lower qualities. 
Additionally, we also recognize that some areas of land cover that we 
identified as suitable could be of such poor quality that it is of 
limited value to the lesser prairie-chicken. We recognize there are 
many important limitations to this landscape analysis, including 
variation and inherent error in the underlying data and unavailable 
data. We interpreted the results of this analysis with those 
limitations in mind.
    In this proposed rule, we discuss effects that relate to the total 
potential usable unimpacted acreage for lesser prairie-chicken, as 
defined by our geospatial analysis (hereafter, analysis area). A 
complete description of the purpose, methodology, constraints, and 
additional details for this analysis is provided in the SSA report for 
the lesser prairie-chicken (Service 2021, Appendix B, Parts 1, 2, and 
3).
Threats Influencing Current Condition
    Following are summary evaluations of the threats analyzed in the 
SSA report for the lesser prairie-chicken: Effects associated with 
habitat degradation, loss, and fragmentation, including conversion of 
grassland to cropland (Factor A), petroleum production (Factor A), wind 
energy development and transmission (Factor A), woody vegetation 
encroachment (Factor A), and roads and electrical distribution lines 
(Factor A); other factors, such as livestock grazing (Factor A), shrub 
control and eradication (Factor A), collision mortality from fences 
(Factor E), predation (Factor C), influence of anthropogenic noise 
(Factor E), fire (Factor A); and extreme weather events (Factor E). We 
also evaluate existing regulatory mechanisms (Factor D) and ongoing 
conservation measures.
    In the SSA report, we also considered three additional threats: 
Hunting and other recreational, educational, and scientific use (Factor 
B); parasites and diseases (Factor C); and insecticides (Factor E). We 
concluded that, as indicated by the best available scientific and 
commercial information, these threats are currently having little to no 
impact on lesser prairie-chickens and their habitat, and thus their 
overall effect now and into the future is expected to be minimal. 
Therefore, we will not present summary analyses of those threats in 
this document but will consider them in our overall conclusions of 
impacts to the species. For full descriptions of all threats and how 
they impact the species, please see the SSA report (Service 2021, pp. 
24-49).
Habitat Degradation, Loss, and Fragmentation
    The grasslands of the Great Plains are among the most threatened 
ecosystems in North America (Samson et al. 2004, p. 6) and have been 
impacted more than any other major ecosystem on the continent (Samson 
and Knopf 1994, p. 418). Temperate grasslands are also one of the least 
conserved ecosystems (Hoekstra et al. 2005, p. 25). Grassland loss in 
the Great Plains is estimated at approximately 70 percent (Samson et 
al. 2004, p. 7), with nearly 93,000 square km (23 million ac; 9.3 
million ha) of grasslands in the United States lost between 1982 and 
1997 alone (Samson et al. 2004, p. 9). The vast majority of the lesser 
prairie-chicken range (>95 percent) occurs on private lands that have 
been in some form of agricultural production since at least the early 
1900s. As a result, available habitat for grassland species, such as 
the lesser

[[Page 29445]]

prairie-chicken, has been much reduced and fragmented compared to 
historical conditions across its range.
    Habitat impacts occur in three general categories that often work 
synergistically at the landscape scale: Degradation, loss, and 
fragmentation. Habitat degradation results in changes to a species' 
habitat that reduces its suitability to the species, but without making 
the habitat entirely unsuitable. Degradation may result in lower 
carrying capacity, lower reproductive potential, higher predation 
rates, or other effects. Habitat loss may result from the same 
anthropogenic sources that cause degradation, but the habitat has been 
altered to the point where it has no suitability for the species at 
all. Habitat fragmentation occurs when habitat loss is patchy and 
leaves a matrix of grassland habitat behind. While habitat degradation 
continues to be a concern, we focus our analysis on habitat loss and 
fragmentation from the cumulative effects of multiple sources of 
activities as the long-term drivers of the species' viability.
    Initially, reduction in the total area of available habitat may be 
more significant than fragmentation and can exert a much greater effect 
on populations (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). Spatial habitat 
fragmentation occurs when some form of disturbance, usually habitat 
degradation or loss, results in the separation or splitting apart of 
larger, previously contiguous, functional components of habitat into 
smaller, often less valuable, noncontiguous patches (Wilcove et al. 
1986, p. 237; Johnson and Igl 2001, p. 25; Franklin et al. 2002, 
entire). Habitat loss and fragmentation influence habitat availability 
and quality in three primary ways: (1) Total area of available habitat 
constrains the maximum population size for an area; (2) the size of 
habitat patches within a larger habitat area, including edge effects 
(changes in population or community structures that occur at the 
boundary of two habitats), influences habitat quality and size of local 
populations; and (3) patch isolation influences the amount of species 
movement between patches, which constrains demographic and genetic 
exchange and ability to recolonize local areas where the species might 
be extirpated (Johnson and Igl 2001, p. 25; Stephens et al. 2003, p. 
101).
    Habitat loss, fragmentation, and degradation correlate with the 
ecological concept of carrying capacity. Within any given block or 
patch of lesser prairie-chicken habitat, carrying capacity is the 
maximum number of birds that can be supported indefinitely by the 
resources available within that area, that is, sufficient food, 
shelter, and lekking, nesting, brood-rearing, and wintering areas. As 
habitat loss increases and the size of an area decreases, the maximum 
number of birds that can inhabit that particular habitat patch also 
decreases. 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 habitat will reduce the capacity of the landscape to 
support historical population levels, causing a decline in population 
sizes.
    Habitat loss not only contributes to overall declines in usable 
area for a species but also causes a reduction in the size of 
individual habitat patches and influences the proximity and 
connectivity of these patches to other patches of similar habitat 
(Stephens et al. 2003, p. 101; Fletcher 2005, p. 342), reducing rates 
of movement between habitat patches until, eventually, complete 
isolation results. Habitat quality for many species is, in part, a 
function of patch size and declines as the size of the patch decreases 
(Franklin et al. 2002, p. 23). Both the size and shape of the habitat 
patch have been shown to influence population persistence in many 
species (Fahrig and Merriam 1994, p. 53). The size of the fragment can 
influence reproductive success, survival, and movements. As the 
distances between habitat fragments increase, the rate of dispersal 
between the habitat patches may decrease and ultimately cease, reducing 
the likelihood of population persistence and potentially leading to 
both localized and regional extinctions (Harrison and Bruna 1999, p. 
226; With et al. 2008, p. 3153). In highly fragmented landscapes, once 
a species becomes extirpated from an area, the probability of 
recolonization is greatly reduced (Fahrig and Merriam 1994, p. 52).
    For the lesser prairie-chicken, habitat loss can occur due to 
either direct or indirect habitat impacts. Direct habitat loss is the 
result of the removal or alteration of grasslands, making that space no 
longer available for use by the lesser prairie-chicken. Indirect 
habitat loss and degradation is when the vegetation still exists, but 
the areas adjacent to a disturbance (the disturbance can be natural or 
manmade) are no longer used by lesser prairie-chicken, are used at 
reduced rates, or the disturbance negatively alters demographic rates 
or behavior in the affected area. In many cases, as discussed in detail 
below for specific disturbances, the indirect habitat loss can greatly 
exceed the direct habitat loss.
    Primarily due to their site fidelity and the need for large, 
ecologically diverse landscapes, lesser prairie-chickens appear to be 
relatively intolerant to habitat alteration, particularly for 
activities that fragment habitat into smaller patches. The birds 
require habitat patches with large expanses of vegetative structure in 
different successional stages to complete different phases in their 
life cycle, and the loss or partial loss of even one of these 
structural components can significantly reduce the overall value of 
that habitat to lesser prairie-chickens (Elmore et al. 2013, p. 4). In 
addition to the impacts on the individual patches, as habitat loss and 
fragmentation increases on the landscape, the juxtaposition of habitat 
patches to each other and to non-habitat areas will change. This 
changing pattern on the landscape can be complex and difficult to 
predict, but the results, in many cases, are increased isolation of 
individual patches (either due to physical separation or barriers 
preventing or limiting movement between patches) and direct impacts to 
metapopulation structure, which could be important for population 
persistence (DeYoung and Williford 2016, pp. 88-91).
    The following sections provide a discussion and quantification of 
the influence of habitat loss and fragmentation on the grasslands of 
the Great Plains within the lesser prairie-chicken analysis area and 
more specifically allow us to characterize the current condition of 
lesser prairie-chicken habitat.
Conversion of Grassland to Cropland
    Historical conversion of grassland to cultivated agricultural lands 
in the late 19th century and throughout the 20th century has been 
regularly cited as an important cause in the rangewide decline in 
abundance and distribution 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). 
Because cultivated grain crops may have provided increased or more 
dependable winter food supplies for lesser prairie-chickens (Braun et 
al. 1994, p. 429), the

[[Page 29446]]

initial conversion of smaller patches of grassland to cultivation may 
have been temporarily beneficial to the short-term needs of the species 
as primitive and inefficient agricultural practices made grain 
available as a food source (Rodgers 2016, p. 18). However, as 
conversion increased, it became clear that landscapes having greater 
than 20 to 37 percent cultivated grains may not support stable lesser 
prairie-chicken populations (Crawford and Bolen 1976a, p. 102). More 
recently, abundances of lesser prairie-chicken increased with 
increasing cropland until a threshold of 10 percent was reached; after 
that, abundance of lesser prairie-chicken declined with increasing 
cropland cover (Ross et al. 2016b, entire). While lesser prairie-
chicken may forage in agricultural croplands, croplands do not provide 
for the habitat requirements of the species life cycle (cover for 
nesting and thermoregulation); thus, lesser prairie-chicken avoid 
landscapes dominated by cultivated agriculture, particularly where 
small grains are not the dominant crop (Crawford and Bolen 1976a, p. 
102).
    As part of the geospatial analysis completed for the SSA, we 
estimated the amount of cropland that currently exists in the four 
ecoregions of the lesser prairie-chicken. These percentages do not 
equate to the actual proportion of habitat loss in the analysis area 
because not all of the analysis area was necessarily suitable lesser 
prairie-chicken habitat; they are only the estimated portion of the 
total analysis area converted from the native vegetation community to 
cropland. About 37 percent of the total area in the Short-Grass/CRP 
Ecoregion; 32 percent of the total area in the Sand Sagebrush 
Ecoregion; 13 percent of the total area in the Mixed-Grass Ecoregion; 
and 14 percent of the total area in the Shinnery Oak Ecoregion of 
grassland have been converted to cropland in the analysis area of the 
lesser prairie-chicken. Rangewide, we estimate about 4,963,000 ac 
(2,009,000 ha) of grassland have been converted to cropland, 
representing about 23 percent of the total analysis area. We note that 
these calculations do not account for all conversion that has occurred 
within the historical range of the lesser prairie-chicken but are 
limited to the amount of cropland within our analysis area. For further 
information, including total acreages impacted, see the SSA report for 
the lesser prairie-chicken (Service 2021 Appendix E and Figure E.1).
    The effects of grassland converted to cropland within the 
historical range of the lesser prairie-chicken have significantly 
impacted the amount of habitat available and how fragmented the 
remaining habitat is for the lesser prairie-chicken, leading to overall 
decreases in resiliency and redundancy throughout the range of the 
lesser prairie-chicken. The impact of cropland has shaped the 
historical and current condition of the grasslands and shrublands upon 
which the lesser prairie-chicken depends.
Petroleum and Natural Gas Production
    Petroleum and natural gas production has occurred over much of the 
estimated historical and current range of the lesser prairie-chicken. 
As demand for energy has continued to increase nationwide, so has oil 
and gas development in the Great Plains. In Texas, for example, active 
oil and gas wells in the lesser prairie-chicken occupied range have 
increased by more than 80 percent over the previous decade (Timmer et 
al. 2014, p. 143). The impacts from oil and gas development extend 
beyond the immediate well sites; they involve activities such as 
surface exploration, exploratory drilling, field development, and 
facility construction, as well as access roads, well pads, and 
operation and maintenance. Associated facilities can include compressor 
stations, pumping stations, and electrical generators.
    Petroleum and natural gas production result in both direct and 
indirect habitat effects to the lesser prairie-chicken (Hunt and Best 
2004, p. 92). Well pad construction, seismic surveys, access road 
development, power line construction, pipeline corridors, and other 
activities can all result in direct habitat loss by removal of 
vegetation used by lesser prairie-chickens. As documented in other 
grouse species, indirect habitat loss also occurs from avoidance of 
vertical structures, noise, and human presence (Weller et al. 2002, 
entire), which all can influence lesser prairie-chicken behavior in the 
general vicinity of oil and gas development areas. These activities 
also disrupt lesser prairie-chicken reproductive behavior (Hunt and 
Best 2004, p. 41).
    Anthropogenic features, such as oil and gas wells, affect the 
behavior of lesser prairie-chickens and alter the way in which they use 
the landscape (Hagen et al. 2011, pp. 69-73; Pitman et al. 2005, 
entire; Hagen 2010, entire; Hunt and Best 2004, pp. 99-104; Plumb et 
al. 2019, pp. 224-227; Sullins et al. 2019, pp. 5-8; Peterson et al. 
2020, entire). Please see the SSA report for a detailed summary of the 
best available scientific information regarding avoidance distances and 
effects of oil and gas development on lesser prairie-chicken habitat 
use (Service 2021, pp. 27-28).
    As part of the geospatial analysis discussed in the SSA report, we 
calculated the amount of usable land cover for the lesser prairie-
chicken that has been impacted (both direct and indirect impacts) by 
oil and natural gas wells in the current analysis area of the lesser 
prairie-chicken, though this analysis did not include all associated 
infrastructure as those data were not available. We used an impact 
radius of 984 ft (300 m) for indirect effects of oil and gas wells. 
These calculations were limited to the current analysis area and do not 
include historical impacts of habitat loss that occurred outside of the 
current analysis area. Thus, the calculation likely underestimates the 
rangewide effects of historical oil and gas development on the lesser 
prairie-chicken. About 4 percent of the total area in the Short-Grass/
CRP Ecoregion; 5 percent of the total area in the Sand Sagebrush 
Ecoregion; about 10 percent of the total area in the Mixed-Grass 
Ecoregion; and 4 percent of the total area in the Shinnery Oak 
Ecoregion of space that was identified as potential usable or potential 
restorable areas have been impacted due to oil and gas development in 
the current analysis area of the lesser prairie-chicken. Rangewide, we 
estimate about 1,433,000 ac (580,000 ha) of grassland have been lost 
due to oil and gas development representing about 7 percent of the 
total analysis area. Maps of these areas in each ecoregion are provided 
in the SSA report (Service 2021, Appendix E, Figure E.2).
    Oil and gas development directly removes habitat that supports 
lesser prairie-chicken, and the effects of the development extend past 
the immediate site of the wells and their associated infrastructure, 
further impacting habitat and altering behavior of lesser prairie-
chicken throughout both the Northern and the Southern DPS. These 
activities have resulted in decreases in population resiliency and 
species redundancy.
Wind Energy Development and Power Lines
    Wind power is a form of renewable energy increasingly being used to 
meet current and projected future electricity demands in the United 
States. Much of the new wind energy development is likely to come from 
the Great Plains States because they have high wind resource potential, 
which exerts a strong, positive influence on the amount of wind energy 
developed within a particular State (Staid and Guikema 2013, p. 384). 
In 2019, three of the five States within the lesser prairie-chicken 
range (Colorado, New Mexico, and Kansas) were within the top 10 States

[[Page 29447]]

nationally for fastest growing States for wind generation in the past 
year (AWEA 2020, p. 33). There is substantial information (Southwest 
Power Pool 2020) indicating interest by the wind industry in developing 
wind energy within the range of the lesser prairie-chicken, especially 
if additional transmission line capacity is constructed. As of May 
2020, approximately 1,792 wind turbines were located within the lesser 
prairie-chicken analysis area (Hoen et al. 2020). Not all areas within 
the analysis area are habitat for the lesser prairie-chicken, so not 
all turbines located within the analysis area affect the lesser 
prairie-chicken and its habitat.
    The average size of installed wind turbines and all other size 
aspects of wind energy development continues to increase (Department of 
Energy (DOE) 2015, p. 63; AWEA 2020, p. 87-88; AWEA 2014, entire; AWEA 
2015, entire; AWEA 2016, entire; AWEA 2017, entire; AWEA 2018, entire; 
AWEA 2019, entire; AWEA 2020, entire). Wind energy developments range 
from 20 to 400 towers, each supporting a single turbine. The individual 
permanent footprint of a single turbine unit, about 0.75-1 ac (0.3-0.4 
ha), is relatively small in comparison with the overall footprint of 
the entire array (DOE 2008, pp. 110-111). Roads are necessary to access 
the turbine sites for installation and maintenance. Depending on the 
size of the wind energy development, one or more electrical 
substations, where the generated electricity is collected and 
transmitted on to the power grid, may also be built. Considering the 
initial capital investment and that the service life of a single 
turbine is at least 20 years (DOE 2008, p. 16), we expect most wind 
energy developments to be in place for at least 30 years. Repower of 
existing wind energy developments at the end of their service life is 
increasingly common, with 2,803 MW of operating projects partially 
repowering in 2019 (AWEA 2020, p. 2).
    Please see the SSA report for a detailed review of the best 
available scientific information regarding the potential effects of 
wind energy development on habitat use by the lesser prairie-chicken 
(Service 2021, pp. 31-33).
    Noise effects to prairie-chickens have been recently explored as a 
way to evaluate potential negative effects of wind energy development. 
For a site in Nebraska, wind turbine noise frequencies were documented 
at less than or equal to 0.73 kHz (Raynor et al. 2017, p. 493), and 
reported to overlap the range of lek-advertisement vocalization 
frequencies of lesser prairie-chicken, 0.50-1.0 kHz. Female greater 
prairie-chickens avoided wooded areas and row crops but showed no 
response in space use based on wind turbine noise (Raynor et al. 2019, 
entire). Additionally, differences in background noise and signal-to-
noise ratio of boom chorus of leks in relation to distance to turbine 
have been documented, but the underlying cause and response needs to be 
further investigated, especially since the study of wind energy 
development noise on grouse is almost unprecedented (Whalen et al. 
2019, entire).
    The effects of wind energy development on the lesser prairie-
chicken must also 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, although 
the vast majority of transmission lines are erected above ground. Most 
of the impacts to lesser prairie-chicken associated with transmission 
lines are with the above ground systems. Support structures vary in 
height depending on the size of the line. Most high-voltage power line 
towers are 98 to 125 ft (30 to 38 m) high but can be higher if the need 
arises. Local distribution lines, if erected above ground, are usually 
much shorter in height but still contribute to fragmentation of the 
landscape.
    The effect of the transmission line infrastructure is typically 
much larger than the physical footprint of transmission line 
installation. Transmission lines can indirectly lead to alterations in 
lesser prairie-chicken behavior and space use (avoidance), decreased 
lek attendance, and increased predation on lesser prairie-chicken. 
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 usable 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. 2009, pp. 1255-1257). Because lesser 
prairie-chicken 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 attendance 
by new males to the lek, as has been reported for sage-grouse (Braun et 
al. 2002, pp. 11-13). Decreased probabilities of use by lesser prairie-
chicken were shown with the occurrence of more than 0.09 mi (0.15 km) 
of major roads, or transmission lines within a 1.2-mi (2-km) radius 
(Sullins et al. 2019, unpaged). Additionally, a recent study 
corroborated numerous authors' (Pitman et al. 2005; Pruett et al. 2009; 
Hagen et al. 2011; Grisham et al. 2014; Hovick et al. 2014a) findings 
of negative effects of power lines on prairie grouse and reported a 
minimum avoidance distance of 1,925.8 ft (587 m), which is similar to 
other studies of lesser prairie-chickens (Plumb et al. 2019, entire).
    As part of our geospatial analysis, we calculated the amount of 
otherwise usable land cover for the lesser prairie-chicken that has 
been impacted (both direct and indirect impacts) by wind energy 
development in the current analysis area of the lesser prairie-chicken. 
We used an impact radii of 5,906 ft (1,800 m) for indirect effects of 
wind turbines and 2,297 ft (700 m) for indirect effects of transmission 
lines. Within our analysis area, the following acreages have been 
identified as impacted due to wind energy development: About 2 percent 
of the total area in the Short-Grass/CRP, Mixed-Grass, and Shinnery Oak 
Ecoregions; and no impacts of wind energy development documented 
currently within the Sand Sagebrush Ecoregion. Rangewide, we estimate 
about 428,000 ac (173,000 ha) of grassland have been impacted by wind 
energy development, representing about 2 percent of the total analysis 
area (Service 2021, Appendix E, Figure E.3). These percentages do not 
account for overlap that may exist with other features that may have 
already impacted the landscape.
    Additionally, according to our geospatial analysis, the following 
acreages within the analysis area have been directly or indirectly 
impacted due to the construction of transmission lines: About 7 percent 
of the total area in the Short-Grass/CRP Ecoregion; 5 percent of the 
total area in the Sand Sagebrush Ecoregion; 7 percent of the total area 
in the Mixed-Grass Ecoregion; and 10 percent of the total area in the 
Shinnery Oak Ecoregion. Rangewide, we estimate about 1,553,000 ac 
(629,000 ha) of grassland have been impacted by transmission lines 
representing about 7 percent of the total analysis area (Service 2021, 
Appendix E, Figure E.4).
    Wind energy development and transmission lines remove habitat that 
supports lesser prairie-chicken. The effects of the development extend 
past the immediate site of the turbines and their associated 
infrastructure, further impacting habitat and altering behavior of 
lesser prairie-chicken throughout

[[Page 29448]]

both the Northern and the Southern DPSs. These activities have resulted 
in decreases in population resiliency and species redundancy.
Woody Vegetation Encroachment
    As discussed in Background, habitat selected by lesser prairie-
chicken is characterized by expansive regions of treeless grasslands 
interspersed with patches of small shrubs (Giesen 1998, pp. 3-4); 
lesser prairie-chicken avoid areas with trees and other vertical 
structures. Prior to extensive Euro-American settlement, frequent fires 
and grazing by large, native ungulates helped confine trees like 
eastern red cedar to river and stream drainages and rocky outcroppings. 
The frequency and intensity of these disturbances directly influenced 
the ecological processes, biological diversity, and patchiness typical 
of Great Plains grassland ecosystems (Collins 1992, pp. 2003-2005; 
Fuhlendorf and Smeins 1999, pp. 732, 737).
    Following Euro-American settlement, increasing fire suppression 
combined with government programs promoting eastern red cedar for 
windbreaks, erosion control, and wildlife cover facilitated the 
expansion of eastern red cedar distribution in grassland areas (Owensby 
et al. 1973, p. 256; DeSantis et al. 2011, p. 1838). 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 so that 
adjacent areas can readily become infested with eastern red cedar. 
Despite the relatively short viability of the seeds (typically only one 
growing season), the large cone crop, potentially large seed dispersal 
ability, and the physiological adaptations of eastern red cedar to 
open, relatively dry sites help make the species a successful invader 
of grassland landscapes (Holthuijzen et al. 1987, p. 1094). Most trees 
are relatively long-lived and, once they become established in 
grassland areas, require intensive management to remove to return areas 
to a grassland state.
    Within the southern- and westernmost portions of the estimated 
historical and occupied ranges of lesser prairie-chicken in Eastern New 
Mexico, Western Oklahoma, and the South Plains and Panhandle of Texas, 
honey mesquite is another common woody invader within these grasslands 
(Riley 1978, p. vii; Boggie et al. 2017, entire). Mesquite is a 
particularly effective invader in grassland habitat due to its ability 
to produce abundant, long-lived seeds that can germinate and establish 
in a variety of soil types and moisture and light regimes (Lautenbach 
et al. 2017, p. 84). Though not as widespread as mesquite or eastern 
red cedar, other tall, woody plants, such as redberry or Pinchot 
juniper (Juniperus pinchotii), black locust (Robinia pseudoacacia), 
Russian olive (Elaeagnus angustifolia), and Siberian elm (Ulmus pumila) 
can also be found in grassland habitat historically and currently used 
by lesser prairie-chicken and may become invasive in these areas.
    Invasion of grasslands by opportunistic woody species causes 
otherwise usable grassland habitat to no longer be used by lesser 
prairie-chicken and contributes to the loss and fragmentation of 
grassland habitat (Lautenbach 2017, p. 84; Boggie et al. 2017, p. 74). 
In Kansas, lesser prairie-chicken are 40 times more likely to use areas 
that had no trees than areas with 1.6 trees per ac (5 trees per ha), 
and no nests occur in areas with a tree density greater than 0.8 trees 
per ac (2 trees per ha), at a scale of 89 ac (36 ha) (Lautenbach 2017, 
pp. 104-142). Similarly, within the Shinnery Oak Ecoregion, lesser 
prairie-chicken space use in all seasons is altered in the presence of 
mesquite, even at densities of less than 5 percent canopy cover (Boggie 
et al. 2017, entire). Woody vegetation encroachment also contributes to 
indirect habitat loss and increases habitat fragmentation because 
lesser prairie-chicken are less likely to use areas adjacent to trees 
(Boggie et al. 2017, pp. 72-74; Lautenbach 2017, pp. 104-142).
    Fire is often the best method to control or preclude tree invasion 
of grassland. However, to some landowners and land managers, burning of 
grassland can be perceived as a high-risk activity because of the 
potential liability of escaped fire impacting nontarget lands and 
property. Additionally, it is undesirable for optimizing cattle 
production and is likely to create wind erosion or ``blowouts'' in 
sandy soils. Consequently, wildfire suppression is common, and 
relatively little prescribed burning occurs on private land. Often, 
prescribed fire is employed only after significant tree invasion has 
already occurred and landowners consider forage production for cattle 
to have diminished. Preclusion of woody vegetation encroachment on 
grasslands of the southern Great Plains using fire requires 
implementing fire at a frequency that mimics historical fire 
frequencies of 2-14 years (Guyette et al. 2012, p. 330), further 
limiting the number of landowners able to implement fire in a manner 
that would truly preclude future encroachment. 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, p. 293; Bragg and 
Hulbert 1976, p. 19) and will not eradicate mesquite.
    As part of our geospatial analysis, we calculated the amount of 
woody vegetation encroachment in the current analysis area of the 
lesser prairie-chicken. These calculations of the current analysis area 
do not include historical impacts of habitat loss that occurred outside 
of the current analysis area; thus, it likely underestimates the 
effects of historical woody vegetation encroachment rangewide on the 
lesser prairie-chicken. An additional limitation associated with this 
calculation is that available remote sensing data lack the ability to 
detect areas with low densities of encroachment, as well as areas with 
shorter trees; thus, this calculation likely underestimates lesser 
prairie-chicken habitat loss due to woody vegetation encroachment. The 
identified areas of habitat impacted by woody vegetation are: About 5 
percent of the total area in the Short-Grass/CRP Ecoregion; about 2 
percent of the total area in the Sand Sagebrush Ecoregion; about 24 
percent of the total area in the Mixed-Grass Ecoregion; and about 17 
percent of the total area in the Shinnery Oak Ecoregion. Rangewide, we 
estimate about 3,071,000 ac (1,243,000 ha) of grassland have been 
directly or indirectly impacted by the encroachment of woody 
vegetation, or about 18 percent of the total area. These percentages do 
not account for overlap that may exist with other features that may 
have already impacted the landscape. Further information, including 
total acres impacted, is available in the SSA report (Service 2021, 
Appendix B; Appendix E, Figure E.5).
    Woody vegetation encroachment is contributing to ongoing habitat 
loss as well as contributing to fragmentation and degradation of 
remaining habitat patches. The effects of woody vegetation encroachment 
are particularly widespread in the Shinnery Oak Ecoregion that makes up 
the Southern DPS as well as the Mixed-Grass Ecoregion of the Northern 
DPS. While there are ongoing efforts to control woody vegetation 
encroachment, the current level of woody vegetation on the landscape is 
evidence that removal efforts are being outpaced by rates of 
encroachment, thus we expect that this threat will continue to 
contribute to habitat loss and fragmentation, which has reduced 
population resiliency

[[Page 29449]]

across the range of the lesser prairie-chicken.
Roads and Electrical Distribution Lines
    Roads and distribution power lines are linear features on the 
landscape that contribute to loss and fragmentation of lesser prairie-
chicken habitat and fragment populations as a result of behavioral 
avoidance. Lesser prairie-chickens are less likely to use areas close 
to roads (Plumb et al. 2019, entire; Sullins et al. 2019, entire). 
Additionally, roads contribute to lek abandonment when they disrupt 
important habitat features (such as affecting auditory or visual 
communication) associated with lek sites (Crawford and Bolen 1976b, p. 
239). Some mammal species that prey on lesser prairie-chicken, such as 
red fox (Vulpes vulpes), raccoons (Procyon lotor), and striped skunks 
(Mephitis mephitis), have greatly increased their distribution by 
dispersing along roads (Forman and Alexander 1998, p. 212; Forman 2000, 
p. 33; Frey and Conover 2006, pp. 1114-1115).
    Traffic noise from roads may indirectly impact lesser prairie-
chicken. Because lesser prairie-chicken 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. For further discussion on noise, please see 
Influence of Anthropogenic Noise.
    Depending on the traffic volume and associated disturbances, roads 
also may limit lesser prairie-chicken dispersal abilities. Lesser 
prairie-chickens avoid areas of usable habitat near roads (Pruett et 
al. 2009, pp. 1256, 1258; Plumb et al. 2019, entire) and in areas where 
road densities are high (Sullins et al. 2019, p. 8). Lesser prairie-
chickens are thought to avoid major roads due to disturbance caused by 
traffic volume and perhaps to avoid exposure to predators that may use 
roads as travel corridors. However, the extent to which roads 
constitute a significant obstacle to lesser prairie-chicken movement 
and space use is largely dependent upon the local landscape composition 
and characteristics of the road itself.
    Local electrical distribution lines are usually much shorter in 
height than transmission lines but can still contribute to habitat 
fragmentation through similar mechanisms as other vertical features 
when erected above ground. Distribution lines are similar to 
transmission lines with the exception to height of poles and electrical 
power carried through the line. In addition to habitat loss and 
fragmentation, electrical power lines can directly affect prairie 
grouse by posing a collision hazard (Leopold 1933, p. 353; Connelly et 
al. 2000, p. 974). There were no datasets available to quantify the 
total impact of distribution lines on the landscape for the lesser 
prairie-chicken. Although distribution lines are a significant 
landscape feature throughout the Great Plains with potential to affect 
lesser prairie-chicken habitat, after reviewing all available 
information, we were unable to develop a method to quantitatively 
incorporate the occurrence of distribution lines into our geospatial 
analysis.
    As part of our geospatial analysis, we estimated the area impacted 
by direct and indirect habitat loss due to roads (Service 2021, 
Appendix B, Part 2). These calculations of the current analysis area do 
not include historical impacts of loss; thus, it likely underestimates 
the historical effect of roads on rangewide habitat loss for the lesser 
prairie-chicken. The results indicate that the total areas of grassland 
that have been directly and indirectly impacted by roads within the 
analysis area for the lesser prairie-chicken are: about 17 percent of 
the total area in the Short-Grass/CRP Ecoregion; about 14 percent of 
the total area in the Sand Sagebrush Ecoregion; about 20 percent of the 
total area in the Mixed-Grass Ecoregion; and about 19 percent of the 
total area in the Shinnery Oak Ecoregion. Rangewide, we estimate about 
3,996,000 ac (1,617,000 ha) of grassland have been impacted by roads, 
representing about 18 percent of the total analysis area (Service 2021, 
Appendix E, Figure E.6). We did not have adequate spatial data to 
evaluate habitat loss caused solely by power lines, but much of the 
existing impacts of power lines occur within the impacts caused by 
roads. Power lines that fall outside the existing impacts of roads 
would represent additional impacts for the lesser prairie-chicken that 
are not quantified in our geospatial analysis.
    Development of roads and electrical distribution lines directly 
removes habitat that supports lesser prairie-chicken, and the effects 
of the development extend past the immediate footprint of the 
development, further impacting habitat and altering behavior of lesser 
prairie-chicken throughout both the Northern and the Southern DPSs. 
These activities have resulted in decreases in population resiliency 
and species redundancy.
Other Factors
Livestock Grazing
    Grazing has long been an ecological driving force throughout the 
ecosystems of the Great Plains (Stebbins 1981, p. 84), and much of the 
untilled grasslands within the range of the lesser prairie-chicken is 
currently grazed by livestock and other animals. Historically, the 
interaction of fire, drought, prairie dogs (Cynomys ludovicianus), and 
large ungulate grazers created and maintained distinctive plant 
communities in the Western Great Plains, resulting in a mosaic of 
vegetation structure and composition that sustained lesser prairie-
chicken and other grassland bird populations (Derner et al. 2009, p. 
112). As such, grazing by domestic livestock is not inherently 
detrimental to lesser prairie-chicken management and, in many cases, is 
needed to maintain appropriate vegetative structure.
    However, grazing practices that tend to result in overutilization 
of forage and decreasing vegetation heterogeneity can produce habitat 
conditions that differ in significant ways from the historical 
grassland mosaic; these incompatible practices alter the vegetation 
structure and composition and degrade the quality of habitat for the 
lesser prairie-chicken. The more heavily altered conditions are the 
least valuable for the lesser prairie-chicken (Jackson and DeArment 
1963 p. 733; Davis et al. 1979, pp. 56, 116; Taylor and Guthery 1980a, 
p. 2; Bidwell and Peoples 1991, pp. 1-2). In some cases, these 
alterations can result in areas that do not contain the biological 
components necessary to support the lesser prairie-chicken.
    Where grazing regimes leave limited residual cover in the spring, 
protection of lesser prairie-chicken nests may be inadequate, and 
desirable food resources can be scarce (Bent 1932, p. 280; Cannon and 
Knopf 1980, pp. 73-74; Crawford 1980, p. 3; Kraft 2016, pp. 19-21). 
Because lesser prairie-chicken depend on medium- and tall-grass species 
for nesting, concealment, and thermal cover that are also 
preferentially grazed by cattle, these plant species needed by lesser 
prairie-chicken can easily be reduced or eliminated by cattle grazing, 
particularly in regions of low rainfall (Hamerstrom and Hamerstrom 
1961, p. 290). In addition, when grasslands are in a deteriorated 
condition due to incompatible grazing and overutilization, the soils 
have less water-holding capacity (Blanco and Lal 2010, p. 9), and the 
availability of succulent vegetation and insects used by lesser 
prairie-chicken chicks is reduced. However, grazing can be beneficial 
to the lesser prairie-chicken

[[Page 29450]]

when management practices produce or enhance the vegetative 
characteristics required by the lesser prairie-chicken.
    The interaction of fire and grazing and its effect on vegetation 
components and structure is likely important to prairie-chickens 
(Starns et al. 2020, entire). On properties managed with patch-burn 
grazing regimes, female greater prairie-chickens selected areas with 
low cattle stocking rates and patches that were frequently burned, 
though they avoided areas that were recently burned (Winder et al. 
2017, p. 171). Patch-burn grazing created preferred habitats for female 
greater prairie-chickens if the regime included a relatively frequent 
fire-return interval, a mosaic of burned and unburned patches, and a 
reduced stocking rate in unburned areas avoided by grazers. When 
managed compatibly, widespread implementation of patch-burn grazing 
could result in significant improvements in habitat quality for 
wildlife in the tall-grass prairie ecosystem (Winder et al. 2017, p. 
165). In the eastern portion of the lesser prairie-chicken range, 
patch-burn grazing resulted in patchy landscapes with variation in 
vegetation composition and structure (Lautenbach 2017, p. 20). Female 
lesser prairie-chickens' use of the diversity of patches in the 
landscape varied throughout their life cycle. They selected patches 
with the greatest time-since-fire and subsequently the most visual 
obstruction for nesting, and they selected sites with less time-since-
fire and greater bare ground and forbs for summer brooding.
    Livestock also inadvertently flush lesser prairie-chicken and 
trample lesser prairie-chicken nests (Toole 2005, p. 27; Pitman et al. 
2006, pp. 27-29). Brief flushing of adults from nests can expose eggs 
and chicks to predation and extreme temperatures. Trampling nests can 
cause direct mortality to lesser prairie-chicken eggs or chicks or may 
cause adults to permanently abandon their nests, ultimately resulting 
in loss of young. Although these effects have been documented, the 
significance of direct livestock effects on the lesser prairie-chicken 
is largely unknown and is presumed not to be significant at a 
population scale.
    In summary, domestic livestock grazing (including management 
practices commonly used to benefit livestock production) has altered 
the composition and structure of grassland habitat, both currently and 
historically, used by the lesser prairie-chicken. Much of the remaining 
remnants of mixed-grass grasslands, while still important to the lesser 
prairie-chicken, exhibit conditions quite different from those prior to 
Euro-American settlement. These changes have reduced the suitability of 
remnant grassland areas as habitat for lesser prairie-chicken. Grazing 
management that has altered the vegetation community to a point where 
the composition and structure are no longer suitable for lesser 
prairie-chicken can contribute to fragmentation within the landscape, 
even though these areas may remain as prairie or grassland. Livestock 
grazing, however, is not inherently detrimental to lesser prairie-
chicken provided that grazing management results in a plant community 
diversity and structure that is suitable for lesser prairie-chicken.
    While domestic livestock grazing is a dominant land use on untilled 
range land within the lesser prairie-chicken analysis area, geospatial 
data do not exist at a scale and resolution necessary to calculate the 
total amount of livestock grazing that is being managed in a way that 
results in habitat conditions that are not compatible with the needs of 
the lesser prairie-chicken. Therefore, we did not attempt to spatially 
quantify the scope of grazing effects across the lesser prairie-chicken 
range.
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-chicken (Jackson and DeArment 1963, pp. 736-
737). Most shrub control and eradication efforts in lesser prairie-
chicken habitat are primarily focused on sand shinnery oak for the 
purpose of increasing forage for livestock grazing. Sand shinnery oak 
is toxic if eaten by cattle when it first produces leaves in the spring 
and competes with more palatable grasses and forbs for water and 
nutrients (Peterson and Boyd 1998, p. 8), which is why it is a common 
target for control and eradication efforts by rangeland managers. Prior 
to the late 1990s, approximately 100,000 ac (40,000 ha) of sand 
shinnery oak in New Mexico and approximately 1,000,000 ac (405,000 ha) 
of sand 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).
    Shrub cover is an important component of lesser prairie-chicken 
habitat in certain portions of the range, and sand shinnery oak is a 
key shrub in the Shinnery Oak and portions of the Mixed-Grass 
Ecoregions. The importance of sand shinnery oak as a component of 
lesser prairie-chicken habitat in the Shinnery Oak Ecoregion has been 
demonstrated by several studies (Fuhlendorf et al. 2002, pp. 624-626; 
Bell 2005, pp. 15, 19-25). In West Texas and New Mexico, lesser 
prairie-chicken avoid nesting where sand shinnery oak has been 
controlled with tebuthiuron, indicating their preference for habitat 
with a sand shinnery oak component (Grisham et al. 2014, p. 18; Haukos 
and Smith 1989, p. 625; Johnson et al. 2004, pp. 338-342; Patten and 
Kelly 2010, p. 2151). Where sand shinnery oak occurs, lesser prairie-
chicken use it both for food and cover. Sand shinnery oak may be 
particularly important in drier portions of the range that experience 
more severe and frequent droughts and extreme heat events, as sand 
shinnery oak is more resistant to drought and heat conditions than are 
most grass species. And because sand shinnery oak is toxic to cattle 
and thus not targeted by grazing, it can provide available cover for 
lesser prairie-chicken nesting and brood rearing during these extreme 
weather events. Loss of this component of the vegetative community 
likely contributed to observed population declines in lesser prairie-
chicken in these areas.
    While relatively wide-scale shrub eradication has occurred in the 
past, geospatial data do not exist to evaluate the extent to which 
shrub eradication has contributed to the habitat loss and fragmentation 
for the lesser prairie-chicken and, therefore, was not included in our 
quantitative analysis. While current efforts of shrub eradication are 
not likely occurring at rates equivalent to that witnessed in the past, 
any additional efforts to eradicate shrubs that are essential to lesser 
prairie-chicken habitat will result in additional habitat degradation 
and thus reduce redundancy and resiliency.
Influence of Anthropogenic Noise
    Anthropogenic noise can be associated with almost any form of human 
activity, and lesser prairie-chicken may exhibit behavioral and 
physiological responses to the presence of noise. In prairie-chickens, 
the ``boom'' call vocalization transmits information about sex, 
territorial status, mating condition, location, and individual identity 
of the signaler and thus is important to courtship activity and long-
range advertisement of the display ground (Sparling 1981, p. 484). The 
timing of displays and frequency of vocalizations are critical 
reproductive behaviors in prairie grouse and appear to have developed 
in response to unobstructed conditions prevalent in prairie habitat and 
indicate that effective communication, particularly during the lekking 
season, operates within a fairly narrow set of acoustic conditions. 
Prairie grouse usually

[[Page 29451]]

initiate displays on the lekking grounds around sunrise, and 
occasionally near sunset, corresponding with times of decreased wind 
turbulence and thermal variation (Sparling 1983, p. 41). Considering 
the narrow set of acoustic conditions in which communication appears 
most effective for breeding lesser prairie-chicken and the importance 
of communication to successful reproduction, human activities that 
result in noises that disrupt or alter these conditions could result in 
lek abandonment (Crawford and Bolen 1976b, p. 239). Anthropogenic 
features and related activities that occur on the landscape can create 
noise that exceeds the natural background or ambient level. When the 
behavioral response to noise is avoidance, as it often is for lesser 
prairie-chicken, noise can be a source of habitat loss or degradation 
leading to increased habitat fragmentation.
    Anthropogenic noise may be a possible factor in the population 
declines of other species of lekking grouse in North America, 
particularly for populations that are exposed to human developments 
(Blickley et al. 2012a, p. 470; Lipp and Gregory 2018, pp. 369-370). 
Male greater prairie-chicken adjust aspects of their vocalizations in 
response to wind turbine noise, and wind turbine noise may have the 
potential to mask the greater prairie-chicken chorus at 296 hertz (Hz) 
under certain scenarios, but the extent and degree of masking is 
uncertain (Whalen 2015, entire). Noise produced by typical oil and gas 
infrastructure can mask grouse vocalizations, compromise the ability of 
female sage-grouse to find active leks when such noise is present, and 
affect nest site selection (Blickley and Patricelli 2012, p. 32; Lipp 
2016, p. 40). Chronic noise associated with human activity leads to 
reduced male and female attendance at noisy leks. Breeding, 
reproductive success, and ultimately recruitment in areas with human 
developments could be impaired by such developments, impacting survival 
(Blickley et al. 2012b, entire). Because opportunities for effective 
communication on the display ground occur under fairly narrow 
conditions, disturbance during this period may have negative 
consequences for reproductive success. Other communications used by 
grouse off the lek, such as parent-offspring communication, may 
continue to be susceptible to masking by noise from human 
infrastructure (Blickley and Patricelli 2012, p. 33).
    No data are available to quantify the areas of lesser prairie-
chicken habitat rangewide that have been affected by noise, but noise 
is a threat that is almost entirely associated with anthropogenic 
features such as roads or energy development. Therefore, through our 
accounting for anthropogenic features we may have inherently accounted 
for all or some of the response of the lesser prairie-chicken to noise 
produced by those features.
    Overall, persistent anthropogenic noise could cause lek attendance 
to decline, disrupt courtship and breeding activity, and reduce 
reproductive success. Noise can also cause abandonment of otherwise 
usable habitat and, as a result, contribute to habitat loss and 
degradation.
Fire
    Fire, or its absence, is understood to be a major ecological driver 
of grasslands in the Southern Great Plains (Anderson 2006, entire; 
Koerner and Collins 2014, entire; Wright and Bailey 1982, pp. 80-137). 
Fire is an ecological process important to maintaining grasslands by 
itself and in coupled interaction with grazing and climate. The 
interaction of these ecological processes results in increasing 
grassland heterogeneity through the creation of temporal and spatial 
diversity in plant community composition and structure and associated 
response of wildlife (Fuhlendorf and Engle 2001, entire; Fuhlendorf and 
Engle 2004, entire; Fuhlendorf et al. 2017a, pp. 169-196).
    Following settlement of the Great Plains, fire management generally 
emphasized prevention and suppression, often coupled with grazing 
pressures that significantly reduced and removed fine fuels (Sayre 
2017, pp. 61-70). This approach, occurring in concert with settlement 
and ownership patterns that occurred in most of the Southern Great 
Plains, meant that the scale of management was relegated to smaller 
parcels than historically were affected. This increase in smaller 
parcels with both intensive grazing and fire suppression resulted in 
the transformation of landscapes from dynamic heterogeneous to largely 
static and homogenous plant communities. This simplification of 
vegetative pattern due to decoupling fire and grazing (Starns et al. 
2019, pp. 1-3) changed the number and size of wildfires and ultimately 
led to declines in biodiversity in the affected systems (Fuhlendorf and 
Engle 2001, entire).
    Changes in patterns of wildfire in the Great Plains have been noted 
in recent years (Donovan et al. 2017, entire). While these landscapes 
have a long history of wildfire, large wildfires (greater than 1,000 ac 
(400 ha)) typically did not occur in recent past decades, and include 
an increase in the Southern Great Plains of megafires (greater than 
100,000 ac (400 km\2\)) since the mid-1990s (Lindley et al. 2019, p. 
164). Changes have occurred throughout all or portions of the Great 
Plains in number of large wildfires and season of fire occurrence, as 
well as increased area burned by wildfire or increasing probability of 
large wildfires (Donovan et al. 2017, p. 5990). Furthermore, Great 
Plains land cover dominated by woody or woody/grassland combined 
vegetation is disproportionately more likely to experience large 
wildfires, with the greatest increase in both number of fires and of 
area burned (Donovan et al. 2020a, p. 11). Fire behavior has also been 
affected such that these increasingly large wildfires are burning under 
weather conditions (Lindley et al. 2019, entire) that result in greater 
burned extent and intensity. These shifts in fire parameters and their 
outcomes have potential consequences for lesser prairie-chicken, 
including: (1) Larger areas of complete loss of nesting habitat as 
compared to formerly patchy mosaicked burns; and (2) large-scale 
reduction in the spatial and temporal variation in vegetation structure 
and composition affecting nesting and brood-rearing habitat, 
thermoregulatory cover, and predator escape cover.
    Effects from fire are expected to be relatively short term (Donovan 
et al. 2020b, entire, Starns et al. 2020, entire) with plant community 
recovery time largely predictable and influenced by pre-fire condition, 
post-fire weather, and types of management. Some effects from fire, 
however, such as the response to changing plant communities in the 
range of the lesser prairie-chicken, will vary based on location within 
the range and available precipitation. In the eastern extent of the 
distribution of sand shinnery oak that occurs in the Mixed-Grass 
Ecoregion, fire has potential negative effects on some aspects of the 
lesser prairie-chicken habitat for 2 years after the area burns, but 
these effects could be longer in duration dependent upon precipitation 
patterns (Boyd and Bidwell 2001, pp. 945-946). Effects from fire on 
lesser prairie-chicken varied based on fire break preparation, season 
of burn, and type of habitat; positive effects included improved brood 
habitat through increased forb and grasshopper abundance, but these can 
be countered by short-term (2-year) negative effects to quality and 
availability of nesting habitat and a reduction in food sources (Boyd 
and Bidwell 2001, pp. 945-946). Birds moved into recently burned 
landscapes of western Oklahoma for lek courtship

[[Page 29452]]

displays because of the reduction in structure from formerly dense 
vegetation (Cannon and Knopf 1979, entire).
    More recently, research evaluating indirect effects concluded that 
prescribed fire and managed grazing following the patch-burn or pyric 
herbivory (grazing practices shaped fire) approach will benefit lesser 
prairie-chicken through increases in forbs; invertebrates; and the 
quality, amount, and juxtaposition of brood habitat to available 
nesting habitat (Elmore et al. 2017, entire). The importance of 
temporal and spatial heterogeneity derived from pyric herbivory is 
apparent in the female lesser prairie-chicken use of all patch types in 
the patch-burn grazing mosaic, including greater than 2 years post-fire 
for nesting, 2-year post fire during spring lekking, 1- and 2-year 
post-fire during summer brooding, and 1-year post-fire during 
nonbreeding season (Lautenbach 2017, pp. 20-22). While the use of 
prescribed fire as a tool for managing grasslands throughout the lesser 
prairie-chicken range is encouraged, current use is at a temporal 
frequency and spatial extent insufficient to support large amount of 
lesser prairie-chicken habitat. These fire management efforts are 
limited to a small number of fire-minded landowners, resulting in 
effects to a small percentage of the lesser prairie-chicken range.
    While lesser prairie-chicken evolved in a fire-adapted landscape, 
little research (Thacker and Twidwell 2014, entire) has been conducted 
on response of lesser prairie-chicken to altered fire regimes. Research 
to date has focused on site-specific responses and consequences. Human 
suppression of wildfire and the limited extent of fire use (prescribed 
fire) for management over the past century has altered the frequency, 
scale, and intensity of fire occurrence in lesser prairie-chicken 
habitat. These changes in fire parameters have happened simultaneously 
with habitat loss and fragmentation, resulting in patchy distribution 
of lesser prairie-chicken throughout their range. An increase in size, 
intensity, or severity of wildfires as compared to historical 
occurrences results in increased vulnerability of isolated, smaller 
lesser prairie-chicken populations. Both woody plant encroachment and 
drought are additive factors that increase risk of negative 
consequences of wildfire ignition, as well as extended post-fire lesser 
prairie-chicken habitat effects. The extent of these negative impacts 
can be significantly altered by precipitation patterns following the 
occurrence of the fire; dry periods will inhibit or extend plant 
community response.
    Historically, fire served an important role in maintenance and 
quality of habitat for the lesser prairie-chicken. Currently, due to a 
significant shift in fire regimes in the lesser prairie-chicken range, 
fire use for management of grasslands plays a locally important but 
overall limited role in most lesser prairie-chicken habitat. This 
current lack of prescribed fire use in the range of the lesser prairie-
chicken is contributing to woody plant encroachment and degradation of 
grassland quality due to its decoupling from the grazing and fire 
interaction that is the foundation for plant community diversity in 
structure and composition, which in turn supports the diverse habitat 
needs of lesser prairie-chicken. These cascading effects contribute to 
greater wildfire risk, and concerns exist regarding the changing 
patterns of wildfires (scale, intensity, and frequency) and their 
consequences for remaining lesser prairie-chicken populations and 
habitat that are increasingly fragmented. Concurrently, wildfire has 
increased as a threat rangewide due to compounding influences of 
increased size and severity of wildfires and the potential consequences 
to remaining isolated and fragmented lesser prairie-chicken 
populations.
Extreme Weather Events
    Weather-related events such as drought, snow, and hail storms can 
influence habitat quality or result in direct mortality of lesser 
prairie-chickens. Although hail storms typically only have a localized 
effect, the effects of snow storms and drought can often be more 
widespread and can affect considerable portions of the lesser prairie-
chicken range. Drought is considered a universal ecological driver 
across the Great Plains (Knopf 1996, p. 147). Annual precipitation 
within the Great Plains is highly variable (Wiens 1974, p. 391), with 
prolonged drought capable of causing local extinctions of annual forbs 
and grasses within stands of perennial species; recolonization is often 
slow (Tilman and El Haddi 1992, p. 263). Grassland bird species in 
particular are impacted by climate extremes such as extended drought, 
which acts as a bottleneck that allows only a limited number of 
individuals to survive through the relatively harsh conditions (Wiens 
1974, pp. 388, 397; Zimmerman 1992, p. 92). Drought also interacts with 
many of the other threats impacting the lesser prairie-chicken and its 
habitat, such as amplifying the effects of incompatible grazing and 
predation.
    Although the lesser prairie-chicken has adapted to drought as a 
component of its environment, drought and the accompanying harsh, 
fluctuating conditions (high temperatures and low food and cover 
availability) have influenced lesser prairie-chicken populations. 
Widespread periods of drought commonly result in ``bust years'' of 
recruitment. Following extreme droughts of the 1930s, 1950s, 1970s, and 
1990s, lesser prairie-chicken population levels declined and a decrease 
in their overall range was observed (Lee 1950, p. 475; Ligon 1953, p. 
1; 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 Giesen 2005, unpaginated). Additionally, lesser prairie-
chicken populations reached near record lows during and after the more 
recent drought of 2011 to 2013 (McDonald et al. 2017, p. 12; Fritts et 
al. 2018, entire).
    Drought impacts prairie grouse, such as 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; Ross 
et al. 2016a, entire). 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 et al. 1996, 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. 2005, pp. 1274-1275; Bell 2005, pp. 20-21; Boal 
et al. 2010, p. 11). Precipitation, or lack thereof, appears to affect 
lesser

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prairie-chicken adult population trends with a potential lag effect 
(Giesen 2000, p. 145; Ross et al. 2016a, pp. 6-8). That is, rain levels 
in one year promote more vegetative cover for eggs and chicks in the 
following year, which influences survival and reproduction.
    Although lesser prairie-chicken have persisted through droughts in 
the past, the effects of such droughts are exacerbated by human land 
use practices such as incompatible grazing 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; Ross et al. 
2016b, pp. 183-186) as well as the other threats that have affected the 
current condition and have altered and fragmented the landscape and 
decreased population abundances (Fuhlendorf et al. 2002, p. 617; 
Rodgers 2016, pp. 15-19). In past decades, fragmentation of lesser 
prairie-chicken habitat was less extensive than it is today, 
connectivity between occupied areas was more prevalent, and populations 
were larger, allowing populations to recover more quickly. In other 
words, lesser prairie-chicken populations were more resilient to the 
effects of stochastic events such as drought. As lesser prairie-chicken 
population abundances decline and usable habitat declines and becomes 
more fragmented, their ability to rebound from prolonged drought is 
diminished.
    Hail storms can cause mortality of prairie grouse, particularly 
during the spring nesting season. 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 (Fleharty 1995, p. 241). 
Although such phenomena are likely rare, the effects can be 
significant, particularly if they occur during the nesting period and 
result in significant loss of eggs or chicks. Severe winter storms can 
also result in localized impacts to lesser prairie-chicken populations. 
For example, a severe winter storm in 2006 was reported to reduce 
lesser prairie-chicken numbers in Colorado by 75 percent 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). While 
populations commonly rebound to some degree following severe weather 
events such as drought and winter storms, a population with decreased 
resiliency becomes susceptible to extirpation from stochastic events.
    We are not able to quantify the impact that severe weather has had 
on the lesser prairie-chicken populations, but, as discussed above, 
these events have shaped recent history and influenced the current 
condition for the lesser prairie-chicken.
Regulatory Mechanisms
    In Appendix D of the SSA report (Service 2021), we review in more 
detail the existing regulatory mechanisms (such as local, State, and 
Federal land use regulations or laws) that may be significant to lesser 
prairie-chicken conservation. Here, we present a summary of some of 
those regulatory mechanisms. All existing regulatory mechanisms were 
fully considered in our conclusion about the status of the two DPSs.
    All five States in the estimated 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 helps heighten public awareness, this designation 
provides no protection from direct take or habitat destruction or 
alteration. The lesser prairie-chicken is listed as threatened in 
Colorado; this listing protects the lesser prairie-chicken from direct 
purposeful mortality by humans but does not provide protections for 
destruction or alteration of habitat.
    Primary land ownership (approximately 5 percent of total range) at 
the Federal level is on USFS and BLM lands. The lesser prairie-chicken 
is present on the Cimarron National Grassland in Kansas and the 
Comanche National Grassland in Colorado; a total of approximately 3 
percent of the total acres estimated in the current condition is on 
USFS land. The 2014 Lesser Prairie-Chicken Management Plan for these 
grasslands provides a framework to manage lesser prairie-chicken 
habitat. The plan provides separate population and habitat recovery 
goals for each grassland, as well as vegetation surveys to inform 
ongoing and future monitoring efforts of suitable habitat and lek 
activities. Because National Grasslands are managed for multiple uses, 
the plan includes guidelines for prescribed fire and grazing.
    In New Mexico, roughly 41 percent of the known historical and most 
of the estimated occupied lesser prairie-chicken range occurs on BLM 
land, for a total of 3 percent of the total acres estimated in the 
current condition. The BLM established the 57,522-ac (23,278-ha) Lesser 
Prairie-Chicken Habitat Preservation Area of Critical Environmental 
Concern (ACEC) upon completion of the Resource Management Plan 
Amendment (RMPA) in 2008. The management goal for the ACEC is to 
protect the biological qualities of the area, with emphasis on the 
preservation of the shinnery oak-dune community to enhance the 
biodiversity of the ecosystem, particularly habitats for the lesser 
prairie-chicken and the dunes sagebrush lizard. Upon designation, the 
ACEC was closed to future oil and gas leasing, and existing leases 
would be developed in accordance with prescriptions applicable to the 
Core Management Area as described below (BLM 2008, p. 30). Additional 
management prescriptions for the ACEC include designation as a right-
of-way exclusion area, vegetation management to meet the stated 
management goal of the area, and limiting the area to existing roads 
and trails for off-highway vehicle use (BLM 2008, p. 31). All acres of 
the ACEC have been closed to grazing through relinquishment of the 
permits except for one 3,442-ac (1,393-ha) allotment.
    The BLM's approved 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. The effect of these best management 
practices on the status of the lesser prairie-chicken is unknown, 
particularly considering about 82,000 ac (33,184 ha) have already been 
leased in those areas (BLM 2008, p. 8). Although the BLM RMPA is an 
important tool for identifying conservation actions that would benefit 
lesser prairie-chicken, this program is not adequate to eliminate 
threats to the species such that is does not warrant listing under the 
Act.
    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). In the southernmost habitat management units, where 
lesser prairie-chickens are now far less common than in previous 
decades (Hunt and Best 2004), new

[[Page 29454]]

leases will not be allowed within 2.4 km (1.5 mi) of a lek (BLM 2008, 
p. 11).
    We conclude that existing regulatory mechanisms have minimal 
influence on the rangewide trends of lesser prairie-chicken habitat 
loss and fragmentation because 97 percent of the lesser prairie-chicken 
analysis area occurs on private lands, and the activities affecting 
lesser prairie-chicken habitat are largely unregulated land use 
practices and land development.
Conservation Efforts
    The SSA report also includes detailed information on current 
conservation measures (Service 2021, pp. 49-61). Some programs are 
implemented across the species' range, and others are implemented at 
the State or local level. Because the vast majority of lesser prairie-
chicken and their habitat occurs on private lands, most of these 
programs are targeted toward voluntary, incentive-based actions in 
cooperation with private landowners.
    At the rangewide scale, plans include the Lesser Prairie-Chicken 
Rangewide Conservation Plan, the Lesser Prairie-Chicken Initiative, and 
the Conservation Reserve Program. Below is a summary of the primary 
rangewide conservation efforts. For detailed descriptions of each 
program, please see the SSA report. All existing ongoing conservation 
efforts were fully considered in our finding on the status of the two 
DPSs.
    In 2013, the State fish and wildlife agencies within the range of 
the lesser prairie-chicken and the Western Association of Fish and 
Wildlife Agencies (WAFWA) finalized the Lesser Prairie-Chicken Range-
wide Conservation Plan (RWP) in response to concerns about threats to 
lesser prairie-chicken habitat and resulting effects to lesser prairie-
chicken populations (Van Pelt et al. 2013, entire). The RWP established 
biological goals and objectives as well as a conservation targeting 
strategy that aims to unify conservation efforts towards common goals. 
Additionally, the RWP establishes a mitigation framework administered 
by WAFWA that allows industry participants the opportunity to mitigate 
unavoidable impacts of a particular activity on the lesser prairie-
chicken. After approval of the RWP, WAFWA developed a companion oil and 
gas candidate conservation agreement with assurances (CCAA), which 
adopted the mitigation framework contained within the RWP that was 
approved in 2014.
    As of August 1, 2020, WAFWA had used incoming funds from industry 
participants to place 22 sites totaling 128,230 unimpacted ac (51,893 
ha) under conservation contracts to provide offset for industry impacts 
that have occurred through the RWP and CCAA (Moore 2020, p. 9). These 
areas are enrolled under RWP conservation contracts that will provide 
mitigation for 1,538 projects, which impacted 48,743 ac (19,726 ha) 
(WAFWA 2020, table 32, unpaginated). When enrolling a property, 
industry participants agree to minimize impacts from projects to lesser 
prairie-chicken habitat and mitigate for all remaining impacts on the 
enrolled property. At the end of 2019 in the CCAA, there were 111 
active contracts (Certificates of Inclusion) with 6,228,136 ac 
(2,520,437 ha) enrolled (Moore 2020, p. 4), and in the WAFWA 
Conservation Agreement there were 52 active WAFWA Conservation 
Agreement contracts (Certificates of Participation) with 599,626 ac 
(242,660 ha) enrolled (WAFWA 2020, Table 5 unpaginated). A recent audit 
of the mitigation program associated with the RWP and CCAA identified 
several key issues to be resolved within the program to ensure 
financial stability and effective conservation outcomes (Moore 2020, 
Appendix E). WAFWA has hired a consultant who is currently working with 
stakeholders, including the Service, to consider available options to 
address the identified issues to ensure long-term durability of the 
strategy.
    In 2010, the U.S. Department of Agriculture's (USDA) Natural 
Resources Conservation Service (NRCS) began implementation of the 
Lesser Prairie-Chicken Initiative (LPCI). The LPCI provides 
conservation assistance, both technical and financial, to landowners 
throughout the LPCI's administrative boundary (NRCS 2017, p. 1). The 
LPCI focuses on maintenance and enhancement of lesser prairie-chicken 
habitat while benefiting agricultural producers by maintaining the 
farming and ranching operations throughout the region. In 2019, after 
annual declines in landowner interest in LPCI, the NRCS made changes in 
how LPCI will be implemented moving forward and initiated conferencing 
under section 7 of the ESA with the Service. Prior to 2019, 
participating landowners had to address all threats to the lesser 
prairie-chicken present on their property. In the future, each 
conservation plan developed under LPCI will only need to include one or 
more of the core management practices that include prescribed grazing, 
prescribed burning, brush management, and upland wildlife habitat 
management. Additional management practices may be incorporated into 
each conservation plan, as needed, to facilitate meeting the desired 
objectives. These practices are applied or maintained annually for the 
life of the practice, typically 1 to 15 years, to treat or manage 
habitat for lesser prairie-chicken. From 2010 through 2019, NRCS worked 
with 883 private agricultural producers to implement conservation 
practices on 1.6 million ac (647,497 ha) of working lands within the 
historical range of the lesser prairie-chicken (NRCS 2020, p. 2). 
During that time, through LPCI, NRCS implemented prescribed grazing 
plans on 680,800 ac (275,500 ha) across the range (Griffiths 2020, 
pers. comm.). Through LPCI, NRCS has also removed over 41,000 ac 
(16,600 ha) of eastern red cedar in the Mixed-Grass Ecoregion and 
chemically treated approximately 106,000 ac (43,000 ha) of mesquite in 
the Shinnery Oak Ecoregion. Lastly, NRCS has conducted prescribed burns 
on approximately 15,000 ac (6,000 ha) during this time.
    The Conservation Reserve Program (CRP) is administered by the 
USDA's Farm Service Agency and provides short-term protection and 
conservation benefits on 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 in exchange for removing cropland and certain marginal 
pastureland from agricultural production. CRP contract terms are for 10 
to 15 years. The total amount of land that can be enrolled in the CRP 
is capped nationally by the Food Security Act of 1985, as amended (the 
2018 Farm Bill) at 27 million ac (10.93 million ha). All five States 
within the range of the lesser prairie-chicken have lands enrolled in 
the CRP. The 2018 Farm Bill maintains the acreage limitation that not 
more than 25 percent of the cropland in any county can be enrolled in 
CRP, with specific conditions under which a waiver to this restriction 
can be provided for lands enrolled under the Conservation Reserve 
Enhancement Program (84 FR 66813, December 6, 2019). Over time, CRP 
enrollment fluctuates both nationally and locally. Within the counties 
that intersect the Estimated Occupied Range plus a 10-mile buffer, 
acres enrolled in CRP have declined annually since 2007 (with the 
exception of one minor increase from 2010 to 2011) from nearly 6 
million ac (2.4 million ha) enrolled to current enrollment levels of 
approximately 4.25 million ac (1.7 million ha) (FSA 2020a, unpublished 
data). More specific to our analysis area, current acreage of CRP 
enrollment is approximately 1,822,000 ac (737,000 ha) within our 
analysis area. Of those currently enrolled acres there

[[Page 29455]]

are approximately 120,000 ac (49,000 ha) of introduced grasses and 
legumes dispersed primarily within the Mixed-Grass and Shinnery Oak 
Ecoregions (FSA 2020b, unpublished data).
    At the State level, programs provide direct technical and financial 
cost-share assistance to private landowners interested in voluntarily 
implementing conservation management practices to benefit species of 
greatest conservation need--including the lesser prairie-chicken. 
Additionally, a variety of State-level conservation efforts acquire and 
manage lands or incentivize management by private landowners for the 
benefit of the lesser prairie-chicken. Below is a summary for each 
State within the range of the lesser prairie-chicken. For a complete 
description of each, see the SSA report. All conservation measures 
discussed in the SSA report were fully considered in this proposed 
rule.
    Within the State of Kansas, conservation efforts are administered 
by the Kansas Department of Wildlife, Parks and Tourism (KDWPT), The 
Nature Conservancy, and the Service's Partners for Fish and Wildlife 
Program (PFW). KDWPT has targeted lesser prairie-chicken habitat 
improvements on private lands by leveraging landowner cost-share 
contributions, industry and nongovernmental organizations' cash 
contributions, and agency funds toward several federally funded grant 
programs. The KDWPT has implemented conservation measures over 22,000 
ac (8,900 ha) through the Landowner Incentive Program, over 18,000 ac 
(7,285 ha) through the State Wildlife Grant Private Landowner Program, 
30,000 ac (12,140 ha) through the Wildlife Habitat Incentives Program, 
and 12,000 ac (4,855 ha) through the Habitat First Program within the 
range of the lesser prairie-chicken. Additionally, KDWPT was provided 
an opportunity through contributions from the Comanche Pool Prairie 
Resource Foundation to leverage additional Wildlife and Sport Fish 
Restoration funds in 2016 to direct implementation of 19,655 ac (7,954 
ha). The Nature Conservancy in Kansas manages the 18,060-ac (7,309-ha) 
Smoky Valley Ranch. The Nature Conservancy also serves as the easement 
holder for nearly 34,000 ac (13,760 ha) of properties that are enrolled 
under the RWP. The Nature Conservancy is also working to use funds from 
an NRCS Regional Conservation Partnership Program that have resulted in 
nearly 50,000 ac (20,235 ha) on three ranches either with secured or 
in-process conservation easements. The Service's PFW program has 
executed 95 private lands agreements with direct and indirect 
improvements on about 173,000 ac (70,011 ha) of private lands 
benefitting conservation of the lesser prairie-chicken in Kansas.
    In 2009, Colorado Parks and Wildlife (CPW) initiated its Lesser 
Prairie-Chicken Habitat Improvement Program that provides cost-sharing 
to private landowners who participate in practices such as deferred 
grazing around active leks, enhancement of fields enrolled in CRP and 
cropland-to-grassland habitat conversion. Since program inception, CPW 
has completed 37,051 ac (14,994 ha) of habitat treatments. The Nature 
Conservancy holds permanent conservation easements on multiple ranches 
that make up the Big Sandy complex. Totaling approximately 48,940 ac 
(19,805 ha), this complex is managed with lesser prairie-chicken as a 
conservation objective and perpetually protects intact sand sagebrush 
and short-grass prairie communities. The USFS currently manages the 
Comanche Lesser Prairie-Chicken Habitat Zoological Area, as part of the 
Comanche and Cimarron National Grasslands, which encompass an area of 
10,177 ac (4,118 ha) in Colorado that is managed to benefit the lesser 
prairie-chicken (USFS 2014, p. 9). In 2016, CPW and KDWPT partnered 
with Kansas State University and USFS to initiate a 3-year 
translocation project to restore lesser prairie-chicken to the Comanche 
National Grasslands (Colorado) and Cimarron National Grasslands 
(Kansas). Beginning in the fall of 2016 and concluding with the 2019 
spring lekking season, the partnership trapped and translocated 411 
lesser prairie-chickens from the Short-Grass/CRP Ecoregion in Kansas to 
the Sand Sagebrush Ecoregion. During April and May 2020 lek counts, 
Colorado and Kansas biologists and technicians found 115 male birds on 
20 active leks in the landscape around the Comanche and Cimarron 
National Grasslands (Rossi 2020, pers. comm.).
    In 2013, the Oklahoma Department of Wildlife Conservation (ODWC) 
was issued a 25-year enhancement of survival permit pursuant to section 
10(a)(1)(A) of the ESA that included an umbrella CCAA between the 
Service and ODWC for the lesser prairie-chicken in 14 Oklahoma counties 
(78 FR 14111, March 4, 2013). As of 2019, there were 84 participants 
with a total of 399,225 ac (161,561 ha) enrolled in the ODWC CCAA, with 
357,654 ac (144,737) enrolled as conservation acres (ODWC 2020). The 
ODWC owns six wildlife management areas totaling approximately 75,000 
ac (30,351 ha) in the range of the lesser prairie-chicken, though only 
a portion of each wildlife management area can be considered as 
conservation acres for lesser prairie-chicken. The Service's PFW 
program has funded a shared position with ODWC for 6 years to conduct 
CCAA monitoring and, in addition, has provided funding for on-the-
ground work in the lesser prairie-chicken range. Since 2017, the 
Oklahoma PFW program has implemented 51 private lands agreements on 
about 10,603 ac (4,291 ha) for the benefit of the lesser prairie-
chicken in Oklahoma. The Nature Conservancy of Oklahoma manages the 
4,050-ac (1,640-ha) Four Canyon Preserve in Ellis County for ecological 
health to benefit numerous short-grass prairie species, including the 
lesser prairie-chicken. In 2017, The Nature Conservancy acquired a 
conservation easement on 1,784 ac (722 ha) in Woods County. The 
Conservancy is seeking to permanently protect additional acreage in the 
region through the acquisition of conservation easements.
    Texas Parks and Wildlife Department (TPWD) worked with the Service 
and landowners to develop the first state-wide umbrella CCAA for the 
lesser prairie-chicken in Texas, which was finalized in 2006. The Texas 
CCAA covers 50 counties, largely encompassing the Texas Panhandle and 
South Plains regions. Total landowner participation by the close of 
January 2020 was 91 properties totaling approximately 657,038 ac 
(265,894 ha) enrolled in 15 counties (TPWD 2020, entire). The Service's 
PFW program and the TPWD have actively collaborated on range management 
programs designed to provide cost-sharing for implementation of habitat 
improvements for lesser prairie-chicken. 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 14,068 ac (5,693 ha) under the Landowner Incentive Program. Typical 
conservation measures include native plant restoration, control of 
exotic or invasive vegetation, prescribed burning, selective brush 
management, and prescribed grazing. The PFW program in Texas has 
executed 66 private lands agreements on about 131,190 ac (53,091

[[Page 29456]]

ha) of privately owned lands for the benefit of the lesser prairie-
chicken in Texas. The Nature Conservancy of Texas acquired 
approximately 10,635 ac (4,303 ha) in Cochran, Terry, and Yoakum 
Counties. In 2014, The Nature Conservancy donated this land to TPWD. 
The TPWD acquired an additional 3,402 ac (1,377 ha) contiguous to the 
Yoakum Dunes Preserve creating the 14,037-ac (5,681-ha) Yoakum Dunes 
Wildlife Management Area. In 2015, through the RWP process, WAFWA 
acquired an additional 1,604 ac (649 ha) in Cochran County, nearly 3 mi 
(5 km) west of the Yoakum Dunes Wildlife Management Area. The land was 
deeded to TPWD soon after acquisition. In 2016, an additional 320 ac 
(129 ha) was purchased by TPWD bordering the WAFWA acquired tract 
creating an additional 1,924-ac (779-ha) property that is being managed 
as part of the Yoakum Dunes Wildlife Management Area, now at 15,961 ac 
(6,459 ha).
    The BLM's Special Status Species RMPA, which was approved in April 
2008, 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 (BLM 2008, entire). Since the RMPA was 
approved in 2008, BLM has closed approximately 300,000 ac (121,000 ha) 
to future oil and gas leasing and closed approximately 850,000 ac 
(344,000 ha) to wind and solar development (BLM 2008, p. 3). From 2008 
to 2020, they have reclaimed 3,500 ac (1,416 ha) of abandoned well pads 
and associated roads and required burial of power lines within 2 mi 
(3.2 km) of lesser prairie-chicken leks. Additionally, BLM has 
implemented control efforts for mesquite on 832,104 ac (336,740 ha) and 
has plans to do so on an additional 30,000 ac (12,141 ha) annually. In 
2010, BLM acquired 7,440 ac (3,010 ha) of land east of Roswell, New 
Mexico, to complete the 54,000-ac (21,853-ha) ACEC for lesser prairie-
chicken, which is managed to protect key habitat.
    Following approval of the RMPA, a candidate conservation agreement 
(CCA) and CCAA was drafted by a team including the Service, BLM, Center 
of Excellence for Hazardous Material Management (CEHMM), and 
participating cooperators to address the conservation needs of the 
lesser prairie-chicken and the dunes sagebrush lizard. Since the CCA 
and CCAA were finalized in 2008, 43 oil and gas companies have enrolled 
a total of 1,964,163 ac (794,868 ha) in the historical range of the 
lesser prairie-chicken. In addition, 72 ranchers in New Mexico and the 
New Mexico Department of Game and Fish have enrolled a total of 
2,055,461 ac (831,815 ha). The New Mexico State Land Office has 
enrolled a total of 406,673 ac (164,575 ha) in the historical range of 
the lesser prairie-chicken. The CCA and CCAA have treated 79,297 ac 
(32,090 ha) of mesquite and reclaimed 154 abandoned well pads and 
associated roads. CEHMM has also removed 7,564 ac (3,061 ha) of dead, 
standing mesquite, and has another 12,000 ac (5,000 ha) scheduled in 
the upcoming 2 years.
    The Nature Conservancy owns and manages the 28,000-ac (11,331-ha) 
Milnesand Prairie Preserve near Milnesand, New Mexico. Additionally, 
the New Mexico Department of Game and Fish has designated 30 Prairie 
Chicken Areas (PCAs) specifically for management of the lesser prairie-
chicken ranging in size from 28 to 7,189 ac (11 to 2,909 ha) and 
totaling more than 27,262 ac (11,033 ha). In 2007, the State Game 
Commission used New Mexico State Land Conservation Appropriation 
funding to acquire 5,285 ac (2,137 ha) of private ranchland in 
Roosevelt County. The Service's PFW program in New Mexico has 
contributed financial and technical assistance for restoration and 
enhancement activities benefitting the lesser prairie-chicken in New 
Mexico. In 2016, the PFW program executed a private land agreement on 
630 ac (255 ha) for treating invasive species with a prescribed burn. 
In 2020 the PFW program executed a private land agreement for a 
prescribed burn on 155 ac (63 ha).
Conditions and Trends
Rangewide Trends
    The lesser prairie-chicken estimated historical range encompasses 
an area of approximately 115 million ac (47 million ha). As discussed 
in Background, not all of the area within this historical range was 
evenly occupied by lesser prairie-chicken, and some of the area may not 
have been suitable to regularly support lesser prairie-chicken 
populations (Boal and Haukos 2016, p. 6). However, the current range of 
the lesser prairie-chicken has been significantly reduced from the 
historical range, and estimates of the reduction vary from greater than 
90 percent (Hagen and Giesen 2005, unpaginated) to approximately 83 
percent (Van Pelt et al. 2013, p. 3).
    We estimated the current amount and configuration of potential 
lesser prairie-chicken usable area within the analysis area using the 
geospatial analysis described in the SSA report (Service 2021, Section 
3.2; Appendix B, Parts 1, 2, and 3) and considering existing impacts as 
described above. The total area of all potential usable (land cover 
that may be consistent with lesser prairie-chicken areas that have the 
potential to support lesser prairie-chicken use) and potential usable, 
unimpacted land cover (that is, not impacted by landscape features) 
categories in each ecoregion and rangewide is shown in Table 1.
    To assess lesser prairie-chicken habitat at a larger scale and 
incorporate some measure of connectivity and fragmentation, we then 
grouped the areas of potential usable, unimpacted land cover based on 
the proximity of other areas with potential usable, unimpacted lesser 
prairie-chicken land cover. To do this, we used a ``nearest neighbor'' 
geospatial process to determine how much potential usable land cover is 
within 1 mi (1.6 km) of any area of potential usable land cover. This 
nearest neighbor analysis gives an estimate of how closely potential 
usable, unimpacted land cover is clustered together, versus spread 
apart, from other potential usable, unimpacted land cover. Areas with 
at least 60 percent potential usable, unimpacted land cover within 1 mi 
(1.6 km) were grouped. The 60 percent threshold was chosen because 
maintaining grassland in large blocks is vital to conservation of the 
species (Ross et al. 2016a, entire; Hagen and Elmore 2016, entire; 
Spencer et al. 2017, entire; Sullins et al. 2019, entire), and these 
studies indicate that landscapes consisting of greater than 60% 
grassland are required to support lesser prairie-chicken populations. 
This approach eliminates small, isolated, and fragmented patches of 
otherwise potential usable land cover that are not likely to support 
persistent populations of the lesser prairie-chicken. A separate 
analysis found that the areas with 60 percent or greater unimpacted 
potential usable land cover within 1 mile (1.6 km) captured 
approximately 90 percent of known leks (Service 2021, Appendix B, Part 
3).

[[Page 29457]]



Table 1--Results of Lesser Prairie-Chicken Geospatial Analysis by Ecoregion and Rangewide, Estimating Total Area
              in Acres, Potential Usable Area, and Area Calculated by Our Nearest Neighbor Analysis
                        [All numbers are in acres. Numbers may not sum due to rounding.]
----------------------------------------------------------------------------------------------------------------
                                                                                      Nearest
                    Ecoregion                        Ecoregion       Potential       neighbor       Percent of
                                                    total area      usable area      analysis       total area
----------------------------------------------------------------------------------------------------------------
Short-Grass/CRP.................................       6,298,014       2,961,318       1,023,894            16.3
Mixed-Grass.....................................       8,527,718       6,335,451         994,483            11.7
Sand Sagebrush..................................       3,153,420       1,815,435       1,028,523            32.6
                                                 ---------------------------------------------------------------
    Northern DPS total..........................      17,979,152      11,112,204       3,046,900            16.9
    Shinnery Oak (Southern DPS total)...........       3,850,209       2,626,305       1,023,572            26.6
                                                 ---------------------------------------------------------------
        Rangewide Totals........................      21,829,361      13,738,509       4,070,472            18.6
----------------------------------------------------------------------------------------------------------------

    The results of the nearest neighbor analysis indicate that about 19 
percent of the entire analysis area and from 12 percent to 33 percent 
within each of the four ecoregions is available for use by the lesser 
prairie-chicken. Due to limitations in data availability and accuracy 
as well as numerous limitations with the methodology and assumptions 
made for this analysis, this estimate should not be viewed as a precise 
measure of the lesser prairie-chicken habitat; instead, it provides a 
generalized baseline to characterize the current condition and by which 
we can then forecast the effect of future changes.
    In the SSA report, we also considered trends in populations. 
Estimates of population abundance prior to the 1960s are indeterminable 
and rely almost entirely on anecdotal information (Boal and Haukos 
2016, p. 6). While little is known about precise historical population 
sizes, the lesser prairie-chicken was reported to be quite common 
throughout its range in the early 20th 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). In the 
1960s, State fish and wildlife agencies began routine lesser prairie-
chicken monitoring efforts that have largely continued to today.
    In the SSA report and this proposed rule, we discuss lesser 
prairie-chicken population estimates from two studies. The first study 
calculated historical trends in lesser prairie-chicken abundances from 
1965 through 2016 based on population reconstruction methods and 
historical lek surveys (Hagen et al. 2017, pp. 6-9). The results of 
these estimates indicate that lesser prairie-chicken rangewide 
abundance (based on a minimum estimated number of male lesser prairie-
chicken) peaked from 1965-1970 at a mean estimate of about 175,000 
males. The mean population estimates maintained levels of greater than 
100,000 males until 1989, after which they steadily declined to a low 
of 25,000 males in 1997 (Garton et al. 2016, p. 68). The mean 
population estimates following 1997 peaked again at about 92,000 males 
in 2006 but subsequently declined to 34,440 males in 2012. The Service 
identified concerns in the past with some of the methodologies and 
assumptions made in this analysis, and the challenges of these data are 
noted in other studies (for example, Zavaleta and Haukos 2013, p. 545; 
Cummings et al. 2017, pp. 29-30). While these concerns remain, 
including the very low sample sizes particularly in the 1960s, this 
work represents the only attempt to compile the extensive historical 
ground lek count data collected by State agencies to estimate rangewide 
population sizes. Approximate distribution of lek locations as reported 
by WAFWA for the entire range that were observed occupied by lesser 
prairie-chicken at least once between 2015 and 2019 are shown in the 
SSA report (Service 2021, Appendix E, Figure E.7).
    Following development of aerial survey methods (McRoberts et al. 
2011, entire), more statistically rigorous estimates of lesser prairie-
chicken abundance (both males and females) have been conducted by 
flying aerial line-transect surveys throughout the range of the lesser 
prairie-chicken and extrapolating densities from the surveyed area to 
the rest of the range beginning in 2012 (Nasman et al. 2020, entire). 
The aerial survey results from 2012 through 2020 (Service 2021, Figure 
3.2) estimated the lesser prairie-chicken population abundance, 
averaged over the most recent 5 years of surveys (2015-2020, no surveys 
in 2019), at 27,384 (90 percent CI: 15,690, 59,981) (Nasman et al. 
2020, p. 21; Table 2). The results of these survey efforts should not 
be taken as precise estimates of the annual lesser prairie-chicken 
population abundance, as indicated by the large confidence intervals. 
Thus, the best use of this data is for long-term trend analysis rather 
than for conclusions based on annual fluctuations. As such, we report 
the population estimate for the current condition as the average of the 
past 5 years of surveys.

Table 2--Rangewide and Ecoregional Estimated Lesser Prairie-Chicken Total Population Sizes Averaged From 2015 to
    2020, Lower and Upper 90 Percent Confidence Intervals (CI) Over the 5 Years of Estimates, and Percent of
     Rangewide Totals for Each Ecoregion (From Nasman et al. 2020, p. 21). No Surveys Were Conducted in 2019
----------------------------------------------------------------------------------------------------------------
                                                      5-Year          5-Year          5-Year
                    Ecoregion                         average     minimum  lower  maximum  upper    Percent of
                                                     estimate           CI              CI             total
----------------------------------------------------------------------------------------------------------------
Short-Grass/CRP.................................          16,957          13,605          35,350              62
Mixed-Grass.....................................           6,135           1,719          11,847              22
Sand Sagebrush..................................           1,215             196           4,547               4
Shinnery Oak....................................           3,077             170           8,237              11
                                                 ---------------------------------------------------------------

[[Page 29458]]

 
    Rangewide Totals............................          27,384          15,690          59,981             100
----------------------------------------------------------------------------------------------------------------

    We now discuss habitat impacts and population trends in each 
ecoregion and DPS throughout the range of the lesser prairie-chicken.
Southern DPS
    Using our geospatial analysis, we were able to explicitly account 
for habitat loss and fragmentation and quantify the current condition 
of the Shinnery Oak Ecoregion. Of the sources of habitat loss and 
fragmentation that have occurred, cropland conversion, roads, and 
encroachment of woody vegetation had the largest impacts on land cover 
in the Southern DPS (Table 3). Based on our nearest neighbor analysis, 
we estimated there are approximately 1,023,572 ac (414,225 ha) or 27 
percent of the ecoregion and the Southern DPS potentially available for 
use by lesser prairie-chicken (Table 1).

   Table 3--Estimated Areas of Current Direct and Indirect Impacts, by
 Impact Source, and the Proportion of the Total Area of the Shinnery Oak
       Ecoregion Estimated To Be Impacted (See Table 1 for Totals)
   [Impacts are not necessarily cumulative because of overlap of some
             impacted areas by more than one impact source.]
------------------------------------------------------------------------
                  Shinnery Oak Ecoregion (Southern DPS)
-------------------------------------------------------------------------
                                                            Percent of
             Impact sources                    Acres         ecoregion
------------------------------------------------------------------------
Cropland Conversion.....................         540,120              14
Petroleum Production....................         161,652               4
Wind Energy Development.................          90,869               2
Transmission Lines......................         372,577              10
Woody Vegetation Encroachment...........         617,885              16
Roads...................................         742,060              19
                                         -------------------------------
    Total Ecoregion/Southern DPS Area...             3,850,209
------------------------------------------------------------------------

    Based on population reconstruction methods, the mean population 
estimate ranged between about 5,000 to 12,000 males through 1980, 
increased to 20,000 males in the mid-1980s and declined to ~1,000 males 
in 1997 (Hagen et al. 2017, pp. 6-9). The mean population estimate 
peaked again to ~15,000 males in 2006 and then declined again to fewer 
than 3,000 males in the mid-2010s.
    Aerial surveys have been conducted to estimate lesser prairie-
chicken population abundance since 2012, and results in the Shinnery 
Oak Ecoregion from 2012 through 2020 (Service 2021, Figure 3.10) 
indicate that this ecoregion has the third highest population size 
(Nasman et al. 2020, p. 21) of the four ecoregions. Average estimates 
from 2015 to 2020 are 3,077 birds (90 percent CI: 170, 8,237), 
representing about 11 percent of the rangewide total (Table 2). Recent 
estimates have varied between fewer than 1,000 birds in 2015 to more 
than 5,000 birds in 2020 (see also Service 2021, Appendix E, Figure 
E.7).
Northern DPS
    Prairies of the Short-Grass/CRP Ecoregion have been significantly 
altered since European settlement of the Great Plains. Much of these 
prairies have been converted to other land uses such as cultivated 
agriculture, roads, power lines, petroleum production, wind energy, and 
transmission lines. Some areas have also been altered due to woody 
vegetation encroachment. Within this ecoregion, it has been estimated 
that about 73 percent of the landscape has been converted to cropland 
with 7 percent of the area in CRP (Dahlgren et al. 2016, p. 262). 
According to our GIS analysis, of the sources of habitat loss and 
fragmentation that have occurred, conversion to cropland has had the 
single largest impact on land cover in this ecoregion (Table 4). Based 
on our nearest neighbor analysis, we estimated approximately 1,023,894 
ac (414,355 ha), or 16 percent of the ecoregion, is potentially 
available for use by lesser prairie-chicken (Table 1).

   Table 4--Estimated Areas of Current Direct and Indirect Impacts, by
 Impact Source, and the Proportion of the Total Area of the Short-Grass/
     CRP Ecoregion Estimated To Be Impacted (See Table 1 for Totals)
   [Impacts are not necessarily cumulative because of overlap of some
             impacted areas by more than one impact source.]
------------------------------------------------------------------------
                        Short-Grass/CRP Ecoregion
-------------------------------------------------------------------------
                                                            Percent of
             Impact sources                    Acres         ecoregion
------------------------------------------------------------------------
Cropland Conversion.....................       2,333,660              37
Petroleum Production....................         248,146               4

[[Page 29459]]

 
Wind Energy Development.................         145,963               2
Transmission Lines......................         436,650               7
Woody Vegetation Encroachment...........         284,175               5
Roads...................................       1,075,931              17
                                         -------------------------------
    Total Ecoregion Area................             6,298,014
------------------------------------------------------------------------

    Based on population reconstruction methods, the mean population 
estimate for this ecoregion increased from a minimum of about 14,000 
males in 2001 and peaked at about 21,000 males in 2011 (Hagen et al. 
2017, pp. 8-10; see also Service 2021, Figure 3.3).
    Aerial surveys since 2012 indicate that the Short-Grass/CRP 
Ecoregion (Figure 3.4) has the largest population size (Nasman et al. 
2020, p. 21) of the four ecoregions. Average estimates from 2015 to 
2020 are 16,957 birds (90 percent CI: 13,605, 35,350), making up about 
62 percent of the rangewide lesser prairie-chicken total (Table 2).
    Much of the Mixed-Grass Ecoregion was originally fragmented by 
home-steading, which subdivided tracts of land into small parcels of 
160-320 ac (65-130 ha) in size (Rodgers 2016, p. 17). As a result of 
these small parcels, road and fence densities are higher compared to 
other ecoregions and, therefore, increase habitat fragmentation and 
pose higher risk for collision mortalities than in other ecoregions 
(Wolfe et al. 2016, p. 302). Fragmentation has also occurred due to oil 
and gas development, wind energy development, transmission lines, 
highways, and expansion of invasive woody plants such as eastern red 
cedar. A major concern for lesser prairie-chicken populations in this 
ecoregion is the loss of grassland due to the rapid westward expansion 
of the eastern red-cedar (NRCS 2016, p. 16). Oklahoma Forestry Services 
estimated the average rate of expansion of eastern red-cedar in 2002 to 
be 762 ac (308 ha) per day (Wolfe et al. 2016, p. 302).

   Table 5--Estimated Areas of Current Direct and Indirect Impacts, by
  Impact Source, and the Proportion (%) of the Total Area of the Mixed-
    Grass Ecoregion Estimated To Be Impacted (See Table 1 for Totals)
   [Impacts are not necessarily cumulative because of overlap of some
             impacted areas by more than one impact source.]
------------------------------------------------------------------------
                          Mixed-Grass Ecoregion
-------------------------------------------------------------------------
                                                            Percent of
             Impact sources                    Acres         ecoregion
------------------------------------------------------------------------
Cropland Conversion.....................       1,094,688              13
Petroleum Production....................         859,929              10
Wind Energy Development.................         191,571               2
Transmission Lines......................         576,713               7
Woody Vegetation Encroachment...........       2,047,510              24
Roads...................................       1,732,050              20
                                         -------------------------------
    Total Ecoregion Area................             8,527,718
------------------------------------------------------------------------

    Using our geospatial analysis, we were able to explicitly account 
for habitat loss and fragmentation and quantify the current condition 
of this ecoregion for the lesser prairie-chicken. Of the sources of 
habitat loss and fragmentation that have occurred, encroachment of 
woody vegetation had the largest impact, with conversion to cropland, 
roads, and petroleum production also having significant impacts on land 
cover in this ecoregion (Table 5). Based on our nearest neighbor 
analysis, we estimated there are approximately 994,483 ac (402,453 ha) 
or 12 percent of the ecoregion, that is potentially available for use 
by lesser prairie-chicken (Table 1).
    The Mixed-Grass Ecoregion historically contained the highest lesser 
prairie-chicken densities (Wolfe et al. 2016, p. 299). Based on 
population reconstruction methods, the mean population estimate for 
this ecoregion in the 1970s and 1980s was around 30,000 males (Hagen et 
al. 2017, pp. 6-7). Population estimates declined in the 1990s and 
peaked again in the early 2000s at around 25,000 males, before 
declining and remaining at its lowest levels, <10,000 males in 2012, 
since the late 2000s (Hagen et al. 2017, pp. 6-7).
    Aerial surveys from 2012 through 2020 (Service 2021, Figure 3.6) 
indicate this ecoregion has the second highest population size of the 
four ecoregions (Nasman et al. 2020, p. 21). Average estimates from 
2015 to 2020 are 6,135 birds (90 percent CI: 1,719, 11,847), 
representing about 22 percent of the rangewide total (Table 2). Results 
show minimal variation in recent years.
    Prairies of the Sand Sagebrush Ecoregion have been influenced by a 
variety of activities since European settlement of the Great Plains. 
Much of these grasslands have been converted to other land uses such as 
cultivated agriculture, roads, power lines, petroleum production, wind 
energy, and transmission lines. Some areas have also been altered due 
to woody vegetation encroachment. Only 26 percent of historical sand 
sagebrush prairie is

[[Page 29460]]

available as potential nesting habitat for lesser prairie-chicken 
(Haukos et al. 2016, p. 285). Using our geospatial analysis, we were 
able to explicitly account for habitat loss and fragmentation and 
quantify the current condition of this ecoregion for the lesser 
prairie-chicken. Of the sources of habitat loss and fragmentation that 
have occurred, conversion to cropland has had the single largest impact 
on land cover in this ecoregion (Table 6). Based on our nearest 
neighbor analysis, we estimated there are approximately 1,028,523 ac 
(416,228 ha) or 33 percent of the ecoregion, potentially available for 
use by lesser prairie-chicken (Table 1). In addition, habitat loss due 
to the degradation of the rangeland within this ecoregion continues to 
be a limiting factor for lesser prairie-chicken, and most of the 
existing birds within this ecoregion persist primarily on and near CRP 
lands. Drought conditions in the period 2011-2014 have expedited 
population decline (Haukos et al. 2016, p. 285).

   Table 6--Estimated Areas of Current Direct and Indirect Impacts, by
   Impact Source, and the Proportion (%) of the Total Area of the Sand
  Sagebrush Ecoregion Estimated To Be Impacted (See Table 1 for Totals)
   [Impacts are not necessarily cumulative because of overlap of some
             impacted areas by more than one impact source.]
------------------------------------------------------------------------
                        Sand Sagebrush Ecoregion
-------------------------------------------------------------------------
                                                            Percent of
             Impact sources                    Acres         ecoregion
------------------------------------------------------------------------
Cropland Conversion.....................         994,733              32
Petroleum Production....................         163,704               5
Wind Energy Development.................               0               0
Transmission Lines......................         167,240               5
Woody Vegetation Encroachment...........          68,147               2
Roads...................................         446,316              14
                                         -------------------------------
    Total Ecoregion Area................             3,153,420
------------------------------------------------------------------------

    Based on population reconstruction methods, the mean population 
estimate for this ecoregion peaked at >90,000 males from 1970 to 1975 
and declined to its lowest level of fewer than 1,000 males in recent 
years.
    Aerial surveys from 2012 through 2020 indicate that this ecoregion 
has the lowest population size (Nasman et al. 2020, p. 21) of the four 
ecoregions. Average estimates from 2015 to 2020 are 1,215 birds (90 
percent CI: 196, 4,547) representing about 4 percent of the rangewide 
lesser prairie-chicken total (Table 2). Recent results have been highly 
variable, with 2020 being the lowest estimate reported. Although the 
aerial survey results show 171 birds in this ecoregion in 2020, (with 
no confidence intervals because the number of detections were too low 
for statistical analysis), ground surveys in this ecoregion in Colorado 
and Kansas detected 406 birds, so we know the current population is 
actually larger than indicated by the aerial survey results (Rossi and 
Fricke, pers. comm. 2020, entire).
    Table 7 combines the estimated area impacted presented above for 
each of the three ecoregions into one estimate for each impact source 
for the Northern DPS.

   Table 7--Estimated Areas of Current Direct and Indirect Impacts, by
 Impact Source, and the Proportion (%) of the Total Area of the Northern
          DPS Estimated To Be Impacted (See Table 1 for Totals)
   [Impacts are not necessarily cumulative because of overlap of some
             impacted areas by more than one impact source.]
------------------------------------------------------------------------
                              Northern DPS
-------------------------------------------------------------------------
             Impact sources                    Acres      Percent of DPS
------------------------------------------------------------------------
Cropland Conversion.....................       4,423,081              25
Petroleum Production....................       1,271,779               7
Wind Energy Development.................         337,534               2
Transmission Lines......................       1,180,603               7
Woody Vegetation Encroachment...........       2,399,832              13
Roads...................................       3,254,297              18
                                         -------------------------------
    Total Northern DPS Area.............            17,979,152
------------------------------------------------------------------------

Future Condition
    As discussed above, we conducted a geospatial analysis to 
characterize the current condition of the landscape for the lesser 
prairie-chicken by categorizing land cover data (into potential usable, 
potential restoration, or non-usable categories), taking into account 
exclusion areas and impacts to remove non-usable areas. We further 
refined the analysis to account for connectivity by use of our nearest 
neighbor analysis as described in Rangewide Trends. We then used this 
geospatial framework to analyze the future condition for each 
ecoregion. To analyze future habitat changes, we accounted for the 
effects of both future loss of usable areas and restoration efforts by 
estimating the rate of change based on future projections (Service 
2021, Figure 4.1).
    Due to uncertainties associated with both future conservation 
efforts and impacts, it is not possible to precisely quantify the 
effect of these future actions on the landscape. Instead, we

[[Page 29461]]

established five future scenarios to represent a range of plausible 
outcomes based upon three plausible levels of conservation (restoration 
efforts) and three plausible levels of impacts. To account for some of 
the uncertainty in these projections, we combined the levels of impacts 
into five different scenarios labeled 1 through 5 (Table 8). Scenario 1 
represents the scenario with low levels of future impacts and high 
levels of future restoration, and Scenario 5 represents the scenario 
with high impacts and low restoration. Scenario 1 and 5 were used to 
frame the range of projected outcomes used in our model as they 
represent the low and high of likely projected outcomes. Scenarios 2, 
3, and 4 are model iterations that fall within the range bounded by 
scenarios 1 and 5 and have continuation of the current level of 
restoration efforts and vary impacts at low, mid, and high levels, 
respectively. These scenarios provide a wide range of potential future 
outcomes to consider in assessing lesser prairie-chicken habitat 
conditions.

    Table 8--Schematic of Future Scenarios for Lesser Prairie-Chicken
   Conservation Considering a Range of Future Impacts and Restoration
                                 Efforts
------------------------------------------------------------------------
                               Levels of future change in usable area
         Scenario         ----------------------------------------------
                                  Restoration              Impacts
------------------------------------------------------------------------
1........................  High....................  Low.
2........................  Continuation............  Low.
3........................  Continuation............  Mid.
4........................  Continuation............  High.
5........................  Low.....................  High.
------------------------------------------------------------------------

    To project the likely future effects of impacts and conservation 
efforts to the landscape as described through our land cover model, we 
quantified the three levels of future habitat restoration and three 
levels of future impacts within the analysis area by ecoregion on an 
annual basis. In addition to restoration efforts, we also quantified 
those efforts that enhance existing habitat. While these enhancement 
efforts do not increase the amount of available area and thus are not 
included in the spatial analysis, they are summarized in the SSA report 
and considered as part of the overall analysis of the biological status 
of the species. We then extrapolated those results over the next 25 
years. We chose 25 years as a period for which we had reasonable 
confidence in reliably projecting these future changes, and the 
timeframe corresponds with some of the long-term planning for the 
lesser prairie-chicken. A complete description of methodology used to 
quantify projections of impacts and future conservation efforts is 
provided in the SSA report (Service 2021, Appendix C).
    Quantifying future conservation efforts in terms of habitat 
restoration allows us to account for the positive impact of those 
efforts within our analysis by converting areas of land cover that were 
identified as potential habitat in our current condition model to 
usable land cover for the lesser prairie-chicken in the future 
projections. Explicitly quantifying three levels of impacts in the 
future allows us to account for the effect of these impacts on the 
lesser prairie-chicken by converting areas identified as usable land 
cover in our current condition model to nonusable area that will not be 
available for use by the lesser prairie-chicken in the future.
    As we did for the current condition to assess habitat connectivity, 
after we characterized the projected effects of conservation and 
impacts on potential future usable areas, we grouped the areas of 
potential usable, unimpacted land cover on these new future landscape 
projections using our nearest neighbor analysis (Service 2021, pp. 21-
24; Appendix B, Parts 1, 2, and 3). Also, as done for the current 
condition, we evaluated the frequency of usable area blocks by size in 
order to evaluate habitat fragmentation and connectivity in the future 
scenarios (Service 2021, Figure 4.2).
Threats Influencing Future Condition
    Following are summary evaluations of the expected future condition 
of threats analyzed in the SSA for the lesser prairie-chicken: Effects 
associated with habitat degradation, loss, and fragmentation, including 
conversion of grassland to cropland (Factor A), petroleum production 
(Factor A), wind energy development and transmission (Factor A), woody 
vegetation encroachment (Factor A), and roads and electrical 
distribution lines (Factor A); climate change (Factor A); and other 
factors, such as livestock grazing (Factor A), shrub control and 
eradication (Factor A), fire (Factor A); and climate change (Factor E).
    In this proposed rule, we do not present summary evaluations of the 
following threats as we have no information to project future trends, 
though we do expect them to have some effect on the species in the 
future: Predation (Factor C), collision mortality from fences (Factor 
E), and influence of anthropogenic noise (Factor E). We also do not 
discuss the following threats, as they are having little to no impact 
on the species and its habitat currently, nor do we expect them to into 
the foreseeable future: Hunting and other recreational, educational, 
and scientific use (Factor B); parasites and diseases (Factor C); and 
insecticides (Factor E).
    For the purposes of this assessment, we consider the foreseeable 
future to be the amount of time on which we can reasonably determine a 
likely threat's anticipated trajectory and the anticipated response of 
the species to those threats. For climate change, the time for which we 
can reliably project threats and the anticipated response is 
approximately 60 years. For many other threats impacting the lesser 
prairie-chicken throughout its range, we consider the time for which we 
can reliably project threats and the anticipated response to be 25 
years. This time period represents our best professional judgment of 
the foreseeable future conditions related to conversion of grassland to 
cropland, petroleum production, wind energy, and woody vegetation 
encroachment, and, as discussed above, is the time period used to 
project these threats in our geospatial analysis. For this period, we 
had reasonable confidence in projecting these future changes, and the 
timeframe corresponds with some of the long-term planning for the 
lesser prairie-chicken. For other threats and the anticipated species 
response, we can reliably project impacts and the species response for 
less than 25 years, such as livestock grazing, roads and electrical 
distribution lines, shrub control and eradication, and fire.
Habitat Loss and Fragmentation
    As discussed in ``Threats Influencing Current Condition,'' habitat 
loss and fragmentation is the primary concern for lesser prairie-
chicken viability. We discuss how each of these activities may 
contribute to future habitat loss and fragmentation for the lesser 
prairie-chicken and present the outcomes of the projections.
Conversion of Grassland to Cropland
    Because much of the lands capable of being used for row crops has 
already been converted to cultivated agriculture, we do not expect 
future rates of conversion to reach those witnessed historically; 
however, conversion has continued to occur (Lark 2020, entire). Rates 
of future conversion of grasslands to cultivated agriculture in the 
analysis area will be affected by multiple variables including site-
specific biotic and abiotic conditions as well as socioeconomic 
influences such as governmental agriculture programs, commodity prices, 
and the economic

[[Page 29462]]

benefits of alternative land use practices.
    For the purposes of the SSA, we conducted an analysis to project 
the future rates of conversion of grassland to cropland at three 
different levels. We used information from aggregated remote sensing 
data from the USDA Cropland Data layer (Lark 2020, entire; Service 
2021, p. 83). Table 9 outlines the resulting three levels of projected 
habitat loss of future conversion of grassland to cultivated 
agriculture per ecoregion over the next 25 years. See the SSA report 
(Service 2021, Appendix C) for further details and methodologies for 
these projections. While we do not expect future rates of conversion 
(from grassland to cropland) to be equivalent to those we have 
historically witnessed, the limited amount of large intact grasslands 
due to the historical extent of conversion means all future impacts are 
expected to have a disproportionate scale of impact.

  Table 9--Future Projection of Three Levels of Impacted Acres of Potential Usable Area for the Lesser Prairie-
            Chicken From Conversion of Grassland to Cropland Over the Next 25 Years in Each Ecoregion
                                     [Numbers may not sum due to rounding.]
----------------------------------------------------------------------------------------------------------------
                                                                             Projected impacts (acres)
                            Ecoregion                            -----------------------------------------------
                                                                        Low        Intermediate        High
----------------------------------------------------------------------------------------------------------------
Short-Grass/CRP.................................................          89,675         145,940         185,418
Mixed-Grass.....................................................           4,220          33,761          50,910
Sand Sagebrush..................................................          42,573          95,678         142,438
    Northern DPS totals.........................................         136,468         275,379         378,766
                                                                 -----------------------------------------------
    Shinnery Oak (Southern DPS).................................          21,985          51,410          93,946
                                                                 -----------------------------------------------
        Rangewide Total.........................................         158,454         326,789         472,712
----------------------------------------------------------------------------------------------------------------

Petroleum Production
    In the SSA report, we conducted an analysis to project the future 
rates of petroleum production at low, intermediate, and high levels. We 
compiled State well permitting spatial data from each State within each 
of the ecoregions to inform assumptions around future rates of 
development (Service 2021, p. 84). We converted the projected number of 
new wells at the three levels to acres of usable area impacted. Our 
analysis accounts for indirect impacts as well as potential overlap 
with other existing impacts to include colocation efforts by 
developers. Table 10 represents the extent of potential usable area 
impacted at the three levels of development per ecoregion over the next 
25 years. See the SSA report (Service 2021, Appendix C) for further 
details and methodologies regarding these projections.
    Given current trends in energy production, we anticipate that oil 
and gas production across the lesser prairie-chicken range will 
continue to occur and that rates will vary both temporally and 
spatially. The rates of development will be dependent upon new 
exploration, advancements in technology, and socioeconomic dynamics 
that will influence energy markets in the future.

  Table 10--Future Projection of Three Levels of Impacted Acres (Including Both Direct and Indirect Effects) of
Potential Usable Area for the Lesser Prairie-Chicken From Oil and Gas Development Over the Next 25 Years in Each
                                                    Ecoregion
                                     [Numbers may not sum due to rounding.]
----------------------------------------------------------------------------------------------------------------
                                                                             Projected impacts (acres)
                            Ecoregion                            -----------------------------------------------
                                                                        Low        Intermediate        High
----------------------------------------------------------------------------------------------------------------
Short-Grass/CRP.................................................          26,848          54,618          82,388
Mixed-Grass.....................................................          82,716         170,989         259,262
Sand Sagebrush..................................................           3,166           9,054          14,942
    Northern DPS totals.........................................         112,730         234,661         356,592
----------------------------------------------------------------------------------------------------------------
    Shinnery Oak (Southern DPS).................................         136,539         190,144         243,749
                                                                 -----------------------------------------------
        Rangewide Total.........................................         249,269         424,805         600,342
----------------------------------------------------------------------------------------------------------------

Wind Energy Development and Transmission Lines
    As discussed in ``Threats Influencing Current Condition,'' the 
States in the lesser prairie-chicken analysis area have experienced 
some of the largest growth in wind energy development in the nation. 
Identification of the actual number of proposed wind energy projects 
that will be built within the range of the lesser prairie-chicken in 
any future timeframe is difficult to accurately discern. We conducted 
an analysis of current and potential future wind energy development for 
the SSA for the Lesser Prairie-Chicken, and the future development was 
estimated at three different levels within the analysis area of the 
lesser prairie-chicken at low, intermediate, and high levels (Service 
2021, Appendix C). Table 11 represents the wind development projects 
projected at three levels of development per ecoregion.

[[Page 29463]]



 Table 11--Projections of Future Wind Energy Development Projects for the Next 25 Years at Three Levels in Each
                                 Lesser Prairie-Chicken Ecoregion and Rangewide
----------------------------------------------------------------------------------------------------------------
                                                                            Projected wind developments
                            Ecoregion                            -----------------------------------------------
                                                                        Low        Intermediate        High
----------------------------------------------------------------------------------------------------------------
Short-Grass/CRP.................................................               7              11              16
Mixed-Grass.....................................................              10              18              25
Sand Sagebrush..................................................               1               2               3
                                                                 -----------------------------------------------
    Northern DPS totals.........................................              18              31              44
    Shinnery Oak (Southern DPS).................................               4               7              10
                                                                 -----------------------------------------------
        Rangewide Total.........................................              22              38              54
----------------------------------------------------------------------------------------------------------------

    As outlined within ``Threats Influencing Current Condition,'' wind 
energy development also has indirect impacts on the lesser prairie-
chicken. To determine the number of acres impacted by wind energy 
development in the current condition, we analyzed wind energy 
facilities recently constructed within and near our analysis area. We 
applied a 5,900-ft (1,800-m) impact radius to individual turbines to 
account for indirect impacts and found that the last 5 years show a 
substantial increase in the relative density of wind energy projects 
(see Service 2021, Appendix C, for further details). This analysis does 
not mean that all of the impacts occur to otherwise usable lesser 
prairie-chicken land cover. In fact, it is highly unlikely due to 
viable wind development potential outside lesser prairie-chicken usable 
areas that all projected impacts will occur in areas that are otherwise 
usable for the lesser prairie-chicken. Because we cannot predict the 
precise location of future developments and to simplify and facilitate 
modeling the locations for future projections for wind development, we 
created a potential wind energy development grid that was laid over the 
analysis area and which allowed the random placement for each 
development for each iteration (Service 2021, p. 86). The resulting 
projected impacts in 25 years using the median iteration for each of 
the range of future scenarios are shown in Table 12. Scenarios 1 and 5 
were used to frame the scenarios used in our model as they represent 
the low and high of likely projected outcomes. The rangewide 
projections range from 164,100 ac (66,400 ha) to 328,000 ac (133,000 
ha).

Table 12--Range of Projections of Future Wind Energy Development Impacts
  (Including Both Direct and Indirect Effects) in Acres for the Next 25
Years for Scenarios 1 and 5 of Each Lesser Prairie-Chicken Ecoregion and
                                Rangewide
------------------------------------------------------------------------
                                            Projected wind  development
                                                  impacts (acres)
                Ecoregion                -------------------------------
                                            Scenario 1      Scenario 5
------------------------------------------------------------------------
Short-Grass/CRP.........................          68,300         134,200
Mixed-Grass.............................          50,200         106,000
Sand Sagebrush..........................           3,900          21,300
                                         -------------------------------
    Northern DPS totals.................         122,400         261,500
    Shinnery Oak (Southern DPS).........          41,700          66,500
                                         -------------------------------
        Rangewide Total.................         164,100         328,000
------------------------------------------------------------------------

    Electrical transmission capacity represents a major limitation on 
wind energy development in the Great Plains. Additional transmission 
lines will be required to transport future electricity production to 
markets; thus, we expect an expansion of the current transmission 
capacity in the Great Plains. As this expansion occurs, these 
transmission lines will, depending on their location, result in habitat 
loss as well as further fragmentation and could also be the catalyst 
for additional wind development affecting the lesser prairie-chicken. 
While we were able to analyze the current impacts of transmission lines 
on the lesser prairie-chicken, due to the lack of information available 
to project the location (and thus effects to lesser prairie-chicken 
habitat), we could not quantify the future potential effect of habitat 
loss and fragmentation on the lesser prairie-chicken that could be 
caused by transmission line development. However, we do acknowledge 
potential habitat loss and fragmentation from transmission lines is 
likely to continue depending upon their location.
Woody Vegetation Encroachment
    Due to the past encroachment trends and continued suppression of 
fire across the range of the lesser prairie-chicken, we expect this 
encroachment of woody vegetation into grasslands to continue, which 
will result in further loss of lesser prairie-chicken habitat into the 
foreseeable future. The degree of future habitat impacts will depend on 
land management practices and the level of conservation efforts for 
woody vegetation removal.
    To describe the potential future effects of encroachment of woody 
vegetation, we used available information regarding rates of increases 
in eastern red cedar and mesquite encroachment and applied this rate of 
change (over the next 25 years) to the amount of existing woody 
vegetation per ecoregion within the analysis area (Appendix C). The 
estimated current condition analysis described in ``Threats

[[Page 29464]]

Influencing Current Condition'' provides the baseline of woody 
vegetation encroachment, and rates derived from the literature were 
applied to this baseline to project new acres of encroachment. We then 
adjusted the projected number of new acres of encroachment using 
relative density calculations specific to each ecoregion to account for 
indirect effects. Additionally, due to assumed differences in 
encroachment rates and tree densities we provide two projections for 
each of the Short-Grass/CRP and Mixed-Grass Ecoregions (East and West 
portions) in the Northern DPS, largely based on current tree 
distribution and precipitation gradient. We projected the extent of 
expected habitat loss due to encroachment of woody vegetation at low, 
intermediate, and high levels of encroachment (see the SSA report 
(Service 2021, Appendix C) for rationale behind assumed rates of 
change). Table 13 outlines the three levels of this projected habitat 
loss by ecoregion caused by future encroachment of woody vegetation 
over the next 25 years for the purpose of the SSA report.

 Table 13--Projection of Impacts From Woody Vegetation Encroachment (Including Both Direct and Indirect Effects)
                       at Three Levels at Year 25 in the Lesser Prairie-Chicken Ecoregions
                                      [Numbers may not sum due to rounding]
----------------------------------------------------------------------------------------------------------------
                                                                             Projected impacts (acres)
                            Ecoregion                            -----------------------------------------------
                                                                        Low        Intermediate        High
----------------------------------------------------------------------------------------------------------------
Short-Grass/CRP--East...........................................          38,830          64,489          93,877
Short-Grass/CRP--West...........................................           1,390           3,598           5,963
Mixed-Grass--East...............................................         311,768         517,784         753,739
Mixed-Grass--West...............................................             874           2,261           3,748
Sand Sagebrush..................................................           7,650          12,706          18,496
                                                                 -----------------------------------------------
    Northern DPS totals.........................................         360,512         600,838         875,823
    Shinnery Oak (Southern DPS).................................          11,548          81,660         170,653
                                                                 -----------------------------------------------
        Rangewide Total.........................................         372,060         682,498       1,046,476
----------------------------------------------------------------------------------------------------------------

Roads and Electrical Distribution Lines
    Roads and electrical distribution lines are another important 
source of habitat loss and fragmentation. In our geospatial analysis 
for the current condition of the lesser prairie-chicken, we were able 
to quantify the area affected by roads, but no data were available to 
quantify the potential independent impacts of distribution lines on 
habitat loss and fragmentation. We acknowledge that some additional 
habitat loss and fragmentation will occur in the future due to 
construction of new roads and power lines, but we do not have data 
available to inform projections on how much and where any potential new 
development would occur.
Climate Change
    Future climate projections for this region of the United States 
indicate general trends of increasing temperatures and increasing 
precipitation extremes over the 21st century (Karl et al. 2009, pp. 
123-128; Kunkel et al. 2013, pp. 73-75; Shafer et al. 2014, pp. 442-
445; Easterling et al. 2017, pp. 216-222; Vose et al. 2017, pp. 194-
199). Average temperature has already increased between the first half 
of the last century (1901-1960) and present day (1986-2016), with 
observed regional average temperatures within the Southern Great Plains 
(including Kansas, Oklahoma, and Texas) increasing by 0.8 [deg]F (0.4 
[deg]C) and within the Southwest (including Colorado and New Mexico) 
increasing by 1.6 [deg]F (0.9 [deg]C) (Vose et al. 2017, p. 187). By 
mid-century (2036-2065), regional average temperatures compared to 
near-present times (1976-2005) are projected to increase by 3.6-4.6 
[deg]F (2.0-2.6 [deg]C) in the Southern Great Plains, and by 3.7-4.8 
[deg]F (2.1-2.7 [deg]C) in the Southwest, depending on future 
emissions. By late-century (2071-2100), regional average temperatures 
are projected to rise in the Southern Great Plans by 4.8-8.4 [deg]F 
(2.7-4.7 [deg]C), and by 4.9-8.7 [deg]F (2.7-4.8 [deg]C) in the 
Southwest (Vose et al. 2017, p. 197). Annual extreme temperatures are 
also consistently projected to rise faster than annual averages with 
future changes in very rare extremes increasing; by late century, 
current 1-in-20 year maximums are projected to occur every year, while 
current 1-in-20 year minimums are not expected to occur at all (Vose et 
al. 2017, pp. 197-198).
    Projecting patterns of changes in average precipitation across 
these regions of the United States results in a range of increasing and 
decreasing precipitation with high uncertainty in overall averages, 
although parts of the Southwest are projected to receive less 
precipitation in the winter and spring (Easterling et al. 2017, pp. 
216-218; Wuebbles et al. 2017, p. 12). However, extreme precipitation 
events are projected to increase in frequency in both the Southern 
Great Plains and the Southwest (Easterling et al. 2017, pp. 218-221). 
Other extreme weather events such as heat waves and long duration 
droughts (Cook et al. 2016, entire), as well as heavy precipitation, 
are expected to become more frequent (Karl et al. 2009, pp. 124-125; 
Shafer et al. 2014, p. 445; Walsh et al. 2014, pp. 28-40). The 
devastating `dust bowl' conditions of the 1930s could become more 
common in the American Southwest, with future droughts being much more 
extreme than most droughts on record (Seager et al. 2007, pp. 1181, 
1183-1184). Other modeling also projects changes in precipitation in 
North America through the end of this century, including an increase in 
dry conditions throughout the Central Great Plains (Swain and Hayhoe 
2015, entire). Furthermore, the combination of increasing temperature 
and drought results in greater impacts on various ecological conditions 
(water availability, soil moisture) than increases in temperature or 
drought alone (Luo et al. 2017, entire). Additionally, future decreases 
in surface (top 4 inches (10 centimeters)) soil moisture over most of 
the United States are likely as the climate warms under higher 
scenarios (Wehner et al. 2017, p. 231).

[[Page 29465]]

    Grasslands are critically endangered globally and an irreplaceable 
ecoregion in North America, and climate change is an emerging threat to 
grassland birds (Wilsey et al. 2019). In a review of potential effects 
of ongoing climate change on the Southern Great Plains and on the 
lesser prairie-chicken, results suggest increases in temperatures 
throughout the lesser prairie-chicken range and possible increases in 
average precipitation in the northern part of the range but decreasing 
precipitation in the southern portion of its range (Grisham et al. 
2016b, pp. 222-227). Weather changes associated with climate change can 
have direct effects on the lesser prairie-chicken, leading to reduced 
survival of eggs, chicks, or adults, and indirect effects on lesser 
prairie-chicken are likely to occur through a variety of means 
including long-term (by mid and late twenty-first century) changes in 
grassland habitat. Other indirect effects may include more secondary 
causes such as increases in predation pressure or susceptibility to 
parasites or diseases. We have little information to describe future 
grassland conditions as a result of long-term climate changes, although 
warmer and drier conditions would most likely reduce overall habitat 
quality for lesser prairie-chicken in much of its range. In general, 
the vulnerability of lesser prairie-chicken to the effects of climate 
change depends on the degree to which it is susceptible to, and unable 
to cope with, adverse environmental changes due to long-term weather 
trends and more extreme weather events. Based on an analysis of future 
climate projections the lesser prairie-chicken could have a net loss of 
more than 35 percent to 50 percent of its range due to unsuitable 
climate variables (Salas et al. 2017, p. 370).
    One area of particular vulnerability for the lesser prairie-chicken 
is the need for specific thermal profiles in the microhabitats they use 
for nesting and rearing of broods. Warmer air and surface soil 
temperatures and the related decreased soil moisture near nest sites 
have been correlated with lower survival and recruitment in the lesser 
prairie-chicken (Bell 2005, pp. 16, 21). On average, lesser prairie-
chicken avoid sites for nesting that are hotter, drier, and more 
exposed to the wind (Patten et al. 2005, p. 1275). Nest survival 
probability decreased by 10 percent every half-hour when temperature 
was greater than 93.2 [deg]F (34 [deg]C) and vapor pressure deficit was 
less than -23 mmHg during the day (Grisham et al. 2016c, p. 737). 
Thermal profiles from nests in some cases exceeded 130 [deg]F (54.4 
[deg]C) with humidity below 10 percent at nests in Texas and New Mexico 
in 2011, which are beyond the threshold for nest survival (Grisham et 
al. 2013, p. 8). Increased temperatures in the late spring as projected 
by climate models may lead to egg death or nest abandonment of lesser 
prairie-chicken (Boal et al. 2010, p. 4). Furthermore, if lesser 
prairie-chicken shift timing of reproduction (to later in the year) to 
compensate for lower precipitation, then impacts from higher summer 
temperatures could be exacerbated. In a study of greater prairie-
chickens, heterogeneous grasslands have high thermal variability with a 
range of measured operative temperatures spanning 41 [deg]F (23 [deg]C) 
with air temperatures >86 [deg]F (30 [deg]C) (Hovick et al. 2014b, pp. 
1-5). In this setting, females selected nest sites that were as much as 
14.4 [deg]F (8 [deg]C) cooler than the surrounding landscape.
    Although the entire lesser prairie-chicken range is likely to 
experience effects from ongoing climate change, the southern part of 
the Southern DPS (the Shinnery Oak Ecoregion) may be particularly 
vulnerable to warming and drying weather trends, as this portion of the 
range is already warmer and drier than northern portions and is 
projected to continue that trend (Grisham et al. 2013, entire; Grisham 
et al. 2016c, p. 742). Research in the Shinnery Oak Ecoregion relating 
projections in weather parameters in 2050 and 2080 to nest survival 
found with high certainty that the negative effects on future nest 
survival estimates will be significant, and the resulting survival 
rates are too low for population sustainability in the Southern Great 
Plains in the absence of other offsetting influences (Grisham et al. 
2013, pp. 6-7). As late spring and summer daily high temperatures rise, 
the ability for lesser prairie-chicken to find appropriate nest sites 
and successfully rear broods is expected to decline. Lower rates of 
successful reproduction and recruitment lead to further overall 
declines in population abundance and resiliency to withstand stochastic 
events such as extreme weather events.
    Extreme weather effects such as drought, heat waves, and storms can 
also directly affect lesser prairie-chicken survival and reproduction 
and can result in population crashes due to species responses including 
direct mortality from thermal stress, increased predation due to larger 
foraging areas, or decreased fitness when food resources are scarce. 
Like other wildlife species in arid and semiarid grasslands, lesser 
prairie-chicken on the Southern High Plains have adaptations that 
increase resilience to extreme environments and fluctuating weather 
patterns; however, environmental conditions expected from climate 
change may be outside of their adaptive potential, particularly in the 
timeframe weather changes are expected to occur (Fritts et al. 2018, p. 
9556). Extreme weather events and periods of drying of soil surface 
moisture are projected to increase across the lesser prairie-chicken 
range (Easterling et al. 2017, pp. 218-222; Wehner et al. 2017, pp. 
237-239). In Kansas, extreme drought events in the summers from 1981 
through 2014 had a significant impact on lesser prairie-chicken 
abundance recorded at leks; thus, increases in drought frequency and 
intensity could have negative consequences for the lesser prairie-
chicken (Ross et al. 2016a, pp. 6-7). Even mild increases in drought 
had significant impacts on the likelihood of population extirpation for 
lesser prairie-chicken (De Angelis 2017, p. 15).
    Drought is a particularly important factor in considering lesser 
prairie-chicken population changes. The lesser prairie-chicken is 
considered a ``boom-bust'' species, meaning that there is a high degree 
of annual variation in population size due to variation in rates of 
successful reproduction and recruitment. These variations are largely 
driven by seasonal precipitation patterns (Grisham et al. 2013, pp. 6-
7). Periods of below-normal precipitation and higher spring/summer 
temperatures result in less appropriate grassland vegetation cover and 
fewer food sources, resulting in decreased reproductive output (bust 
periods). Periods with favorable climatic conditions (above-normal 
precipitation and cooler spring/summer temperatures) will support 
favorable lesser prairie-chicken habitat conditions and result in high 
reproductive success (boom periods). The lesser prairie-chicken 
population failed to rebound for at least 4 years following the 2011 
drought (Fritts et al. 2018, pp. 9556-9557). This information indicates 
either that the extreme environmental conditions during 2011 may have 
been beyond what the lesser prairie-chicken is adapted to or that the 
return period following the 2008-2009 dry period and ensuing low 
population numbers in 2010 was too short for the population to recover 
enough to be resilient to the 2011 drought.
    The resilience and resistance of species and ecosystems to changing 
environmental conditions depend on many circumstances (Fritts et al. 
2018, entire). As climatic conditions shift to more frequent and 
intense drought cycles, this shift is expected to result in more 
frequent and extreme bust years for the lesser prairie-chicken and 
fewer

[[Page 29466]]

boom years. As the frequency and intensity of droughts increase in the 
Southern Great Plains region, there will be diminishing opportunity for 
boom years with above-average precipitation. Overall, more frequent and 
intense droughts may lessen the intensity of boom years of the lesser 
prairie-chicken population cycle in the future which would limit the 
ability of the species to rebound following years of drought (Ross et 
al. 2018, entire). These changes will reduce the overall resiliency of 
lesser prairie-chicken populations and exacerbate the effects of 
habitat loss and fragmentation. Because lesser prairie-chicken carrying 
capacities have already been much reduced, if isolated populations are 
extirpated due to seasonal weather conditions, they cannot be 
repopulated due to the lack of nearby populations.
    Although climate change is expected to alter the vegetation 
community across the lesser prairie-chicken range (Grisham et al. 
2016b, pp. 228-231), we did not account for the future effects of 
climate change in our geospatial habitat model, as we did not have 
information to inform specific land cover changes predicted to result 
from future climate change (Service 2021, p. 92).
    The best available information supports that climate change 
projections of increased temperatures, increased precipitation 
extremes, increased soil drying, and an increase of severe events such 
as drought and storms within the Southern Great Plains are likely to 
have significant influences on the future resiliency of lesser prairie-
chicken populations by mid to late 21st century. These trends are 
expected to exacerbate the challenges related to past and ongoing 
habitat loss and fragmentation, making it less likely for populations 
to withstand extreme weather events that are likely to increase in 
frequency and severity.
Other Factors
Livestock Grazing
    We expect that grazing will continue to be a primary land use on 
the remaining areas of grassland within the range of the lesser 
prairie-chicken in the future, and grazing influences habitat 
suitability for the lesser prairie-chicken (Diffendorfer et al. 2015, 
p. 1). When managed to produce habitat conditions that are beneficial 
for the lesser prairie-chicken, grazing is an invaluable tool for 
maintaining healthy prairie ecosystems. However, if grazing is managed 
in a way that is focused on maximizing short-term cattle production, 
resulting in rangeland that is overused, this could have significant 
negative effects on the lesser prairie-chicken. Grazing management 
varies both spatially and temporally across the landscape. 
Additionally, grazing management could become more difficult in the 
face of a changing climate with more frequent and intense droughts.
    Our geospatial model does not account for impacts to habitat 
quality as data needed to characterize habitat quality for the lesser 
prairie-chicken at the scale and resolution needed for our analysis do 
not exist. While data do not exist to quantify rangewide extent of 
grazing practices and their effects on habitat, livestock grazing will 
continue to influence lesser prairie-chicken populations in the 
foreseeable future.
Shrub Control and Eradication
    The removal of native shrubs such as sand shinnery oak is an 
ongoing concern to lesser prairie-chicken habitat availability 
throughout large portions of its range, particularly in New Mexico, 
Oklahoma, and Texas. While relatively wide-scale shrub eradication has 
occurred in the past, we do not have geospatial data to evaluate the 
extent to which shrub eradication has contributed to habitat loss and 
fragmentation for the lesser prairie-chicken. While some Federal 
agencies such as BLM limit this practice in lesser prairie-chicken 
habitat, shrub control and eradication still occur through some Federal 
programs and on private lands, which make up the majority of the lesser 
prairie-chicken range. Though we expect this threat to continue to 
impact the species into the foreseeable future, we do not have data 
available to project the potential scale of habitat loss likely to 
occur in the future due to shrub eradication.
Fire
    As discussed in ``Threats Influencing Current Condition,'' the 
current lack of prescribed fire use in the range of the lesser prairie-
chicken is contributing to woody plant encroachment and degradation of 
grassland quality.
    As the effects of fire suppression continue to manifest throughout 
the Great Plains, the future impacts of wildfires on the lesser 
prairie-chicken are difficult to predict. If recent patterns continue 
with wildfires occurring at increasingly larger scales with less 
frequency and higher intensities than historical fire occurrence, there 
is an increasing potential of greater negative impacts on lesser 
prairie-chicken. Additionally, as climate change projections are 
indicating the possibility of longer and more severe droughts across 
the range of the lesser prairie-chicken, this could alter the 
vegetation response to fire both temporally and spatially. An expansive 
adoption of prescribed fire in management of remaining grasslands would 
be expected to have a moderating effect on risk of wildfires and 
concurrently would reduce woody plant encroachment and increase habitat 
quality and diversity. We are not able to quantify these impacts on the 
future condition of the landscape in our geospatial analysis due to 
lack of data and added complexity, but we acknowledge that fire (both 
prescribed fires and wildfire), or its absence, will continue to be an 
ecological driver across the range of the lesser prairie-chicken in the 
future with potentially positive and negative effects across both 
short-term and long-term timelines in the foreseeable future.
Projected Future Habitat Conditions and Trends
    To forecast the potential changes in future lesser prairie-chicken 
habitat, we used the projected levels of potential future impacts from 
conversion to cropland, petroleum production, wind energy development, 
and woody vegetation encroachment. We also worked with the primary 
conservation entities delivering ongoing, established lesser prairie-
chicken conservation programs to develop estimated reasonable 
projections for rates of future conservation efforts. We asked the 
entities to provide us with information to project three levels of 
conservation: Low, continuation, and high. We asked the conservation 
entities not provide aspirational goals for a given program but instead 
to solely use past performance, funding expectations, and expert 
opinion to provide plausible future rates for given conservation 
practices. We then used this information to estimate future 
conservation efforts over the next 25 years for the lesser prairie-
chicken.
    The results of this future geospatial model (Service 2021, Section 
4.2 and Appendices B and C) is provided in Table 14; further details 
and maps are available in Appendix E of the SSA report. The median 
results show a very modest increase in areas available for use by 
lesser prairie-chicken in our nearest neighbor analysis under Scenario 
1 (assuming high levels of restoration and low levels of impacts) (with 
an increase for the Shinnery Oak Ecoregion and a decrease for the other 
three ecoregions) and decreasing amounts of projected declines in areas 
available for use by lesser prairie-chicken under Scenarios 2-5 (Table 
14). Rangewide changes in areas available for use by lesser prairie-
chicken in our nearest neighbor analysis range from a

[[Page 29467]]

0.5 percent increase under Scenario 1 to a 26 percent decrease in 
Scenario 5. This analysis indicated additional future habitat loss and 
fragmentation across the range of the lesser prairie-chicken is likely 
to occur, and conservation actions will not be enough to offset those 
habitat losses. Our analysis finds that the expected conservation 
efforts are inadequate to prevent continued declines in total habitat 
availability, much less restore some of what has been lost, and species 
viability for this species will continue to decline.
BILLING CODE 4333-15-P

[[Page 29468]]

[GRAPHIC] [TIFF OMITTED] TP01JN21.022

BILLING CODE 4333-15-C

[[Page 29469]]

    It is important to note that these acreages consist of patches of 
fragmented habitat among developed areas and other unsuitable habitat. 
Based on our geospatial analysis, the vast majority of blocks of usable 
habitat and the total area within those blocks, both in the current 
condition and in future scenarios, are less than 12,000 ac (4,856 ha), 
and very few blocks were greater than 50,000 ac (20,234 ha) (Service 
2021, Figure 4.2). As discussed above, the space required by lesser 
prairie-chicken to support individuals from a single lek is 
approximately 12,000-50,000 ac (4,856-20,234 ha). The dominance of 
smaller blocks on the landscape further exhibits that those spaces are 
highly fragmented, even with the remaining potential usable area for 
the lesser prairie-chicken totaling approximately 4,000,000 ac 
(1,600,000 ha) in the current condition, and potentially declining to 
as low as 3,000,000 ac (1,200,000 ha) under scenario 5 for our future 
condition projections. High levels of fragmentation, as discussed in 
``Threats Influencing Current Condition,'' do not provide the landscape 
composition needed for long-term stability of populations. 
Additionally, in spaces that are highly fragmented, relatively small 
amounts of additional impacts may have great consequences as landscape 
composition thresholds for the lesser prairie-chicken are surpassed.
    Several habitat enhancement actions for the lesser prairie-chicken 
are being implemented across the analysis area. These enhancement 
actions are implemented on existing habitat to enhance the quality of 
that given area. We asked our conservation partners to provide us with 
a range of plausible rates for conservation efforts occurring within 
the lesser prairie-chicken analysis area by ecoregion. We also 
requested information regarding effectiveness, project lifespan, and 
spatial targeting of these efforts (Service 2021, Appendix C, Section 
C.3.4). Next, we converted those rates for each program and 
conservation effort to the total effort at year 25. Table 15 summarizes 
the three projected levels of future habitat enhancement over the next 
25 years for each ecoregion. These efforts represent those above and 
beyond what is already accounted for within the current condition 
analysis. Acreage enrolled in CCAAs are assumed to continue to be 
enrolled in the future, and CCAA projections within this table 
represent enrollments in addition to existing enrollments. This table 
also does not include continued management actions on permanently 
protected properties (such as State-owned wildlife management areas or 
conservation banks), as it is assumed this management will continue. 
Additionally, the numbers reported for NRCS grazing plans are acres in 
addition to the number of acres reported above in ``Conservation 
Efforts'' that are being managed under prescribed grazing for the 
lesser prairie-chicken by NRCS, as we assume that as contract acres 
expire from the program additional acres will be enrolled.
    The actual conservation benefit provided to the lesser prairie-
chicken by these programs varies greatly and is difficult to summarize 
because it depends on the location and the specific actions being 
carried out for each individual agreement. In addition, the level of 
future voluntary participation in these programs can be highly variable 
depending on available funding, opportunities for other revenue 
sources, and many other circumstances.

   Table 15--Projected Amount of Habitat Enhancement (in Acres) Over the Next 25 Years Within the Four Lesser
                                           Prairie-Chicken Ecoregions
----------------------------------------------------------------------------------------------------------------
                                                                   Total level of future effort (acres) at year
                                                                                        25
                       Enhancement efforts                       -----------------------------------------------
                                                                        Low        Continuation        High
----------------------------------------------------------------------------------------------------------------
                                            Short-Grass/CRP Ecoregion
----------------------------------------------------------------------------------------------------------------
KDWPT Enhancement Contract......................................               0           6,740          17,500
NRCS LPCI Grazing Plan..........................................               0               0           4,000
USFWS PFW Contract..............................................          14,000          14,000          20,000
----------------------------------------------------------------------------------------------------------------
                                              Mixed-Grass Ecoregion
----------------------------------------------------------------------------------------------------------------
WAFWA Management Plan...........................................               0               0         118,245
KDWPT Enhancement Contract......................................               0             120           3,100
ODWC Management.................................................           1,400           3,300           6,400
ODWC Additional CCAA Enrollment.................................               0          50,000         100,000
NRCS LPCI Grazing Plan..........................................               0               0          58,000
USFWS PFW Contract..............................................          50,000          50,000          70,000
TPWD Additional CCAA Enrollment.................................               0               0         550,000
----------------------------------------------------------------------------------------------------------------
                                            Sand Sagebrush Ecoregion
----------------------------------------------------------------------------------------------------------------
KDWPT Enhancement Contract......................................               0             720           4,400
CPW Enhancement Contract........................................               0          12,200          37,900
NRCS LPCI Grazing Plan..........................................               0               0          13,000
USFWS PFW Contract..............................................               0           6,000          18,000
----------------------------------------------------------------------------------------------------------------
                                             Shinnery Oak Ecoregion
----------------------------------------------------------------------------------------------------------------
WAFWA Management Plan...........................................               0               0           8,129
NRCS LPCI Grazing Plan..........................................               0               0          39,000
BLM Prescribed Fire.............................................               0          25,000         100,000
NM CCAA Prescribed Fire.........................................          50,000         100,000         150,000
USFWS PFW Contract..............................................           5,000          15,000          50,000
TPWD Additional CCAA Enrollment.................................               0               0          60,000
----------------------------------------------------------------------------------------------------------------


[[Page 29470]]

Future Population Trends
    Several estimates of lesser prairie-chicken population growth rates 
have been based on current conditions for the lesser prairie-chicken, 
with most derived from demographic matrix models (Fields 2004, pp. 76-
83; Hagen et al. 2009, entire; Sullins 2017, entire; Cummings et al. 
2017, entire). Most studies project declining lesser prairie-chicken 
populations; however, the magnitude of actual future declines is 
unlikely to be as low as some modeling tools indicate (Service 2021, 
Table 4.10). Most positive population growth calculations were derived 
from 2014-2016 (Hagen et al. 2017, Supplemental Information; Service 
2021, Table 4.10), where estimates indicated populations have 
increased. However, we caution that any analysis using growth rates 
based upon short-term data sets can be problematic as they are very 
sensitive to the starting and ending points in the estimates. 
Additionally, these growth rates are accompanied by relatively large 
margins of error.
    Estimates based on aerial surveys over the past 9 years have 
indicated a rangewide fluctuating population beginning with an 
estimated 28,366 (90 percent CI: 17,055-40,581) individuals in 2012 to 
an estimated 34,408 (90 percent CI: 21,270-47,946) individuals in 2020. 
Included within this timeframe was a population low of 15,397 (90 
percent CI: 8,145-22,406) individuals in 2013. We caution against 
drawing inferences from point estimates based upon these data due to 
low detection probabilities of the species leading to large confidence 
intervals. We also caution that trend analyses from short-term data 
sets are highly sensitive to starting and ending population sizes. For 
example, if you use 2012, the first year of available rangewide survey 
data, as the starting point for a trend analysis, it may appear that 
populations are relatively stable to slightly increasing, but during 
the years of 2010-2013, the range of the lesser prairie-chicken 
experienced a severe drought and thus lesser prairie-chicken 
populations were at historic lows. If the data existed to perform the 
same analysis using the starting point as 2009, then the results would 
likely show a decreasing population trend.
    The future risk of extinction of the lesser prairie-chicken has 
been evaluated using historical ground surveys (Garton et al. 2016, pp. 
60-73). This analysis used the results of those surveys to project the 
risk of lesser prairie-chicken quasi-extinction in each of the four 
ecoregions and rangewide over two timeframes, 30 and 100 years into the 
future. For this analysis, quasi-extinction was set at effective 
population sizes (demographic Ne) of 50 (populations at 
short-term extinction risk) and 500 (populations at long-term 
extinction risk) adult breeding birds, corresponding to an index based 
on minimum males counted at leks of <=85 and <=852, respectively 
(Garton et al. 2016, pp. 59-60). The initial analysis using data 
collected through 2012 was reported in Garton et al. (2016, pp. 60-73), 
but it has since been updated to include data collected through 2016 
(Hagen et al. 2017, entire). We have identified concerns in the past 
with some of the methodologies and assumptions made in this analysis, 
and the challenges of these data are noted in Zavaleta and Haukos 
(2013, p. 545) and Cummings et al. (2017, pp. 29-30). While these 
concerns remain, this work represents one of the few attempts to 
project risk to the species across its range, and we considered it as 
part of our overall analysis and recognize any limitations associated 
with the analysis.
    Results were reported for each analysis assuming each ecoregion is 
functioning as an independent population and also assuming there is 
movement of individuals between populations (Service 2021, Table 4.11; 
Table 4.12). The results suggest a wide range of risks among the 
ecoregions, but the Sand Sagebrush Ecoregion consistently had the 
highest risks of quasi-extinction and the Short-Grass/CRP Ecoregion had 
the lowest. This analysis was based only on simulating demographic 
variability of populations and did not incorporate changing 
environmental conditions related to habitat or climate.

Determination of Lesser Prairie-Chicken Status

    Section 4 of the Act (16 U.S.C. 1533) and its implementing 
regulations (50 CFR part 424) set forth the procedures for determining 
whether a species meets the definition of an endangered species or a 
threatened species. The Act defines ``endangered species'' as a species 
``in danger of extinction throughout all or a significant portion of 
its range,'' and ``threatened species'' as a species ``likely to become 
an endangered species within the foreseeable future throughout all or a 
significant portion of its range.'' The Act requires that we determine 
whether a species meets the definition of ``endangered species'' or 
``threatened species'' because of any of the following 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.
Status of the Southern DPS of the Lesser Prairie-Chicken Throughout All 
of Its Range
    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
to the Southern DPS of the lesser prairie-chicken and its habitat. We 
analyzed effects associated with habitat degradation, loss, and 
fragmentation, including conversion of grassland to cropland (Factor 
A), petroleum production (Factor A), wind energy development and 
transmission (Factor A), woody vegetation encroachment (Factor A), and 
roads and electrical distribution lines (Factor A); other factors, such 
as livestock grazing (Factor A), shrub control and eradication (Factor 
A), collision mortality from fences (Factor E), predation (Factor C), 
influence of anthropogenic noise (Factor E), and fire (Factor A); and 
extreme weather events (Factor E). We also analyzed the effects of 
existing regulatory mechanisms (Factor D) and ongoing conservation 
measures. In the SSA report, we also considered three additional 
threats: Hunting and other recreational, educational, and scientific 
use (Factor B); parasites and diseases (Factor C); and insecticides 
(Factor E). We consider all of these impacts now in analyzing the 
status of the Southern DPS.
    Over the past several decades, habitat loss, fragmentation, and 
degradation have resulted in the loss of large areas of the habitat 
that supports the lesser prairie-chicken in the Southern DPS. Suitable 
habitat has been lost as grasslands are converted to cropland, and as 
petroleum and natural gas production and wind energy development have 
resulted in further loss of habitat. The lesser prairie-chicken is 
particularly vulnerable to changes on the landscape, as it requires 
large blocks of suitable habitat to complete its life-history needs. 
This includes its 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. In 
the case of petroleum and wind energy production, the extent of the 
impact from the threat is not just the original site, but also all 
roads, powerlines, and other infrastructure associated with the sites, 
and noise

[[Page 29471]]

associated with those areas that may interfere with communication 
between male and female birds.
    In the Southern DPS, woody vegetation encroachment by honey 
mesquite has played a significant role in limiting available space for 
the lesser prairie-chicken and is one of the primary threats to the 
species in this DPS. Fire, incompatible grazing management, and drought 
associated with climate change also continue to degrade habitat. The 
size of fires, especially in areas dominated by woody vegetation, are 
increasing. When managed compatibly, fire and grazing can improve 
habitat quality. However, fire management efforts are currently 
occurring on only a limited portion of the lesser prairie-chicken 
range.
    The Southern DPS is particularly vulnerable to effects associated 
with climate change and drought, as it is already warmer and drier than 
the Northern DPS. That warmer and drier trend is expected to continue 
(Grisham et al. 2013, entire; Grisham et al. 2016c, p. 742). Given the 
needs of lesser prairie-chicken for cool microclimates to find 
appropriate nest sites and rear broods, droughts like those that have 
recently occurred on the landscape could further impact already 
declining population growth rates in this DPS.
    Some conservation measures and regulatory mechanisms are acting to 
reduce the magnitude of threats impacting the lesser prairie-chicken 
and its habitat. However, our analysis demonstrates that the 
restoration efforts have not been enough to offset the impacts of 
habitat loss and fragmentation and conservation efforts focused on 
localized management to affect habitat quality, while not addressing 
the overarching limiting factor of habitat loss and fragmentation, is 
not addressing the long-term population needs for the lesser prairie-
chicken. Thus, these measures are only minimally ameliorating the 
threats acting throughout the DPS.
    After evaluating threats to the species and assessing the 
cumulative effect of the threats under the section 4(a)(1) factors, we 
conclude that the Southern DPS is continuing to experience ongoing 
habitat loss and fragmentation, and additional threats from influence 
of anthropogenic noise and extreme weather events, particularly 
droughts. Currently, only 27 percent of this ecoregion is available for 
use by the lesser prairie-chicken. Based on mean population estimates, 
the Southern DPS has very low resiliency to stochastic events. It may 
have as few as 5,000 birds remaining. The population count dropped to 
as low as 1,000 birds in 2015 after the last severe drought. Under 
current climactic conditions, another wide-scale severe drought could 
occur in this ecoregion at any time, and the species may not be able to 
recover. Overall, the lesser prairie-chickens in the Southern DPS are 
likely to continue to experience declines in resiliency, redundancy, 
and genetic representation. Thus, after assessing the best available 
information, we determine that the Southern DPS of the lesser prairie-
chicken is in danger of extinction throughout all of its range. We find 
that a threatened species status is not appropriate for the Southern 
DPS because it is currently in danger of extinction.
Status of the Southern DPS of the Lesser Prairie-Chicken Throughout a 
Significant Portion of Its Range
    Under the Act and our implementing regulations, a species may 
warrant listing if it is in danger of extinction or likely to become so 
in the foreseeable future throughout all or a significant portion of 
its range. We have determined that the Southern DPS of the lesser 
prairie-chicken is in danger of extinction throughout all of its range 
and accordingly did not undertake an analysis of any significant 
portion of its range. Because the Southern DPS of the lesser prairie-
chicken warrants listing as endangered throughout all of its range, our 
determination is consistent with the decision in Center for Biological 
Diversity v. Everson, 2020 WL 437289 (D.D.C. Jan. 28, 2020), in which 
the court vacated the aspect of the Final Policy on Interpretation of 
the Phrase ``Significant Portion of Its Range'' in the Endangered 
Species Act's Definitions of ``Endangered Species'' and ``Threatened 
Species'' (79 FR 37578; July 1, 2014) that provided the Services do not 
undertake an analysis of significant portions of a species' range if 
the species warrants listing as endangered throughout all of its range.
Determination of Status of the Southern DPS of the Lesser Prairie-
Chicken
    Our review of the best available scientific and commercial 
information indicates that the Southern DPS of the lesser prairie-
chicken meets the definition of an endangered species. Therefore, we 
propose to list the Southern DPS of the lesser prairie-chicken as an 
endangered species in accordance with sections 3(6) and 4(a)(1) of the 
Act.
Status of the Northern DPS of the Lesser Prairie-Chicken Throughout All 
of Its Range
    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
to the Northern DPS of the lesser prairie-chicken and its habitat. We 
analyzed effects associated with habitat degradation, loss, and 
fragmentation, including conversion of grassland to cropland (Factor 
A), petroleum production (Factor A), wind energy development and 
transmission (Factor A), woody vegetation encroachment (Factor A), and 
roads and electrical distribution lines (Factor A); other factors, such 
as livestock grazing (Factor A), shrub control and eradication (Factor 
A), collision mortality from fences (Factor E), predation (Factor C), 
influence of anthropogenic noise (Factor E), and fire (Factor A); and 
extreme weather events (Factor E). We also analyzed existing regulatory 
mechanisms (Factor D) and ongoing conservation measures. In the SSA 
report, we also considered three additional threats: Hunting and other 
recreational, educational, and scientific use (Factor B); parasites and 
diseases (Factor C); and insecticides (Factor E). As with the Southern 
DPS, we consider all of these impacts now in analyzing the status of 
the Northern DPS.
    As is the case in the Southern DPS, habitat degradation, loss, and 
fragmentation is the primary threat to the lesser prairie-chicken in 
this DPS, with other threats such as fire, incompatible livestock 
grazing, and extreme weather events further decreasing population 
resiliency and species redundancy. The largest impacts in this DPS are 
cropland conversion and woody vegetation encroachment. The Sand 
Sagebrush Ecoregion is also experiencing habitat degradation due to 
incompatible grazing management. The Short-Grass/CRP region has the 
highest number of birds, with a 5-year estimate of approximately 17,000 
birds. Other portions of the range have lower population resiliency. In 
particular, the Sand Sagebrush Ecoregion has approximately 1,000 birds 
remaining (Table 2).
    Resiliency of populations throughout the Northern DPS has decreased 
from historical levels, though the DPS still has redundancy across the 
three ecoregions and genetic and environmental representation. However, 
our future scenario analysis demonstrates that the current threats 
acting on the landscape are expected to either continue at the same 
levels or increase in severity in the foreseeable

[[Page 29472]]

future. Habitat loss is projected to outpace conservation efforts to 
restore habitat. Though we do not expect rates of habitat conversion to 
cropland to be equivalent to the rates that we historically witnessed, 
we expect any additional conversion that does occur will have a 
disproportionately large effect on resiliency and redundancy due to the 
limited amount of remaining large intact grasslands. Conversion of 
habitat due to oil, gas, and wind energy will continue to occur, though 
the rates of development are uncertain. Woody vegetation encroachment 
is also expected to continue, particularly in the Mixed-Grass 
Ecoregion. Increased drought and severe weather events associated with 
climate change are expected to decrease population resiliency and 
redundancy into the foreseeable future, and as habitat availability 
continues to decline, and available habitat blocks decrease in size, 
populations may decline to below quasi-extinction levels. Our future 
scenarios project that usable habitat will decrease from 3-25 percent 
within the Northern DPS (5-24 percent in the Short-Grass/CRP Ecoregion, 
from 2-37 percent in the Mixed-Grass Ecoregion, and from 3-14 percent 
in the Sand Sagebrush Ecoregion) due to projected impacts from 
conversion to cropland, energy development, and woody vegetation 
encroachment.
    Conservation measures and regulatory mechanisms are acting to 
reduce the magnitude of threats impacting the lesser prairie-chicken 
and its habitat. However, our analysis demonstrates that future 
restoration efforts will not be enough to offset the impacts of habitat 
loss and fragmentation and conservation efforts focused on localized 
management to affect habitat quality, while not addressing the 
overarching limiting factor of habitat loss and fragmentation, is not 
addressing the long-term population needs for the lesser prairie-
chicken. Thus, these measures are having only minimal impacts on 
threats acting throughout the DPS.
    After evaluating threats to the species and assessing the 
cumulative effect of the threats under the section 4(a)(1) factors, we 
find that the lesser prairie-chicken maintains populations in all three 
ecoregions in the Northern DPS, and has genetic and ecological 
representation in those ecoregions, as well as population redundancy 
across the entirety of the DPS. Thus, lesser prairie-chicken in the 
Northern DPS are not currently in danger of extinction, and thus the 
Northern DPS does not meet the definition of endangered. However, based 
on our future projections, habitat will become increasingly fragmented 
and less able to support lesser prairie-chickens. Thus, after assessing 
the best available information, we conclude that the Northern DPS of 
the lesser prairie-chicken is not currently in danger of extinction but 
is likely to become in danger of extinction within the foreseeable 
future throughout all of its range.
Status of the Northern DPS of the Lesser Prairie-Chicken Throughout a 
Significant Portion of Its Range
    Under the Act and our implementing regulations, a species may 
warrant listing if it is in danger of extinction or likely to become so 
in the foreseeable future throughout all or a significant portion of 
its range. The court in Center for Biological Diversity v. Everson, 
2020 WL 437289 (D.D.C. Jan. 28, 2020) (Everson), vacated the aspect of 
the 2014 Significant Portion of its Range Policy that provided that the 
Services do not undertake an analysis of significant portions of a 
species' range if the species warrants listing as threatened throughout 
all of its range. Therefore, we proceed to evaluating whether the 
species is endangered in a significant portion of its range--that is, 
whether there is any portion of the species' range for which both (1) 
the portion is significant; and (2) the species is in danger of 
extinction in that portion. Depending on the case, it might be more 
efficient for us to address the ``significance'' question or the 
``status'' question first. We can choose to address either question 
first. Regardless of which question we address first, if we reach a 
negative answer with respect to the first question that we address, we 
do not need to evaluate the other question for that portion of the 
species' range.
    We apply the term ``significant'' differently for the purpose of 
the ``significant portion of the range'' analysis than the DPS 
analysis. The DPS Policy requires that for a vertebrate population to 
meet the Act's definition of ``species,'' the population must be 
discrete from other populations and must be significant to the taxon as 
a whole. The use of ``significant to the taxon as a whole'' under the 
DPS Policy is necessarily broad. Notably, a segment could be 
``significant to the taxon as a whole'' for the DPS policy but not be 
``significant'' for the different analysis under the Significant 
Portion of Its Range Policy. Thus, a determination that an area is 
significant for the purposes of DPS does not necessarily mean that it 
will be significant for the purposes of the Significant Portion of Its 
Range Policy.
    Following the court's holding in Center for Biological Diversity, 
we now consider whether there are any significant portions of the 
species' range where the species is in danger of extinction now (i.e., 
endangered). In undertaking this analysis for the Northern DPS of the 
lesser prairie-chicken, we choose to address the status question 
first--we consider information pertaining to the geographic 
distribution of both the species and the threats that the species faces 
to identify any portions of the range where the species is endangered. 
We evaluated all parts of the Northern DPS, including the Sand 
Sagebrush Ecoregion, the Mixed Grass Ecoregion, and the Short Grass/CRP 
Ecoregion. We identified one portion, the Sand Sagebrush Ecoregion, 
that may meet the definition of endangered, as population estimates 
have shown the greatest declines in that portion of the range.
    For the Northern DPS, we considered whether the threats are 
geographically concentrated in any portion of the species' range at a 
biologically meaningful scale. We examined the following threats: 
Effects associated with habitat degradation, loss, and fragmentation, 
including conversion of grassland to cropland, petroleum production, 
wind energy development and transmission, woody vegetation 
encroachment, and roads and electrical distribution lines; other 
factors, such as livestock grazing, shrub control and eradication, 
collision mortality from fences, predation, influence of anthropogenic 
noise, and fire; extreme weather events, including cumulative effects. 
However, we did not identify any threats that were concentrated in the 
Sand Sagebrush Ecoregion that were not at similar levels in the 
remainder of the range at a biologically meaningful scale.
    Thus, there are no portions of the DPS's range where the species 
has a different status from its rangewide status. Therefore, no portion 
of the species' range provides a basis for determining that the species 
is in danger of extinction in a significant portion of its range, and 
we determine that the species is likely to become in danger of 
extinction within the foreseeable future throughout all of its range. 
This is consistent with the courts' holdings in Desert Survivors v. 
Department of the Interior, No. 16-cv-01165-JCS, 2018 WL 4053447 (N.D. 
Cal. Aug. 24, 2018), and Center for Biological Diversity v. Jewell, 248 
F. Supp. 3d, 946, 959 (D. Ariz. 2017).

[[Page 29473]]

Determination of Status of the Northern DPS of the Lesser Prairie-
Chicken
    Our review of the best available scientific and commercial 
information indicates that the Northern DPS of the lesser prairie-
chicken meets the definition of a threatened species. Therefore, we 
propose to list the Northern DPS of the lesser prairie-chicken as a 
threatened species in accordance with sections 3(20) and 4(a)(1) of the 
Act.

Available Conservation Measures

    Conservation measures provided to species listed as endangered or 
threatened species under the Act include recognition, recovery actions, 
requirements for Federal protection, and prohibitions against certain 
practices. Recognition through listing results in public awareness, and 
conservation by Federal, State, Tribal, and local agencies, private 
organizations, and individuals. The Act encourages cooperation with the 
States and other countries and calls for recovery actions to be carried 
out for listed species. The protection required by Federal agencies and 
the prohibitions against certain activities are discussed, in part, 
below.
    The primary purpose of the Act is the conservation of endangered 
and threatened species and the ecosystems upon which they depend. The 
ultimate goal of such conservation efforts is the recovery of these 
listed species, so that they no longer need the protective measures of 
the Act. Section 4(f) of the Act calls for 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 consists of preparing draft and final recovery 
plans, beginning with the development of a recovery outline and making 
it available to the public within 30 days of a final listing 
determination. The recovery outline guides the immediate implementation 
of urgent recovery actions and describes the process to be used to 
develop a recovery plan. Revisions of the plan may be done to address 
continuing or new threats to the species, as new substantive 
information becomes available. The recovery plan also identifies 
recovery criteria for review of when a species may be ready for 
reclassification from endangered to threatened (``downlisting'') or 
removal from protected status (``delisting''), 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 (composed of 
species experts, Federal and State agencies, nongovernmental 
organizations, and stakeholders) are often established to develop 
recovery plans. When completed, the recovery outline, draft recovery 
plan, and the final recovery plan will be available on our website 
(http://www.fws.gov/endangered), or from our Arlington Field Office 
(see FOR FURTHER INFORMATION CONTACT).
    Implementation of recovery actions generally requires the 
participation of a broad range of partners, including other Federal 
agencies, States, Tribes, nongovernmental organizations, businesses, 
and private landowners. Examples of recovery actions include habitat 
restoration (such as restoration of native vegetation), research, 
captive propagation and reintroduction, and outreach and education. 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. To achieve recovery of these species requires 
cooperative conservation efforts on private, State, and 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, 
pursuant to 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 or 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 Southern DPS and the Northern DPS of the lesser 
prairie-chicken are only proposed for listing under the Act at this 
time, please let us know if you are interested in participating in 
recovery efforts for the lesser prairie-chicken. Additionally, we 
invite you to submit any new information on this species whenever it 
becomes available and any information you may have for recovery 
planning purposes (see FOR FURTHER INFORMATION CONTACT).
    Section 7(a) of the Act requires Federal agencies to evaluate their 
actions with respect to any species that is proposed or listed as an 
endangered or threatened species 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) of the Act 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 affect a listed species or its critical habitat, the 
responsible Federal agency must enter into 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, the State Wildlife 
Grant Program, and the 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 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 
Environmental Quality Incentive Program and CRP; and development of 
Federal minerals, such as oil and gas.
    The Act and its implementing regulations set forth a series of 
general prohibitions and exceptions that apply to endangered wildlife. 
The prohibitions of section 9(a)(1) of the Act, codified at 50 CFR 
17.21, make it illegal for any person subject to the jurisdiction of 
the United States to take (which includes harass, harm, pursue, hunt, 
shoot, wound, kill, trap, capture, or collect; or to attempt any of 
these) endangered

[[Page 29474]]

wildlife within the United States or on the high seas. In addition, it 
is unlawful to import; export; deliver, receive, carry, transport, or 
ship in interstate or foreign commerce in the course of commercial 
activity; or sell or offer for sale in interstate or foreign commerce 
any species listed as an endangered species. It is also illegal to 
possess, sell, deliver, carry, transport, or ship any such wildlife 
that has been taken illegally. Certain exceptions apply to employees of 
the Service, the National Marine Fisheries Service, other Federal land 
management agencies, and State conservation agencies.
    We may issue permits to carry out otherwise prohibited activities 
involving endangered wildlife under certain circumstances. Regulations 
governing permits are codified at 50 CFR 17.22. With regard to 
endangered wildlife, a permit may 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. There are also certain statutory exemptions from the 
prohibitions, which are found in sections 9 and 10 of the Act.
    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 the 
species proposed for listing. For the Northern DPS of the lesser 
prairie-chicken, which we are proposing to list as threatened, the 
discussion below in section II regarding protective regulations under 
section 4(d) of the Act complies with our policy.
    We now discuss specific activities related to the Southern DPS, 
which we are proposing to list as endangered. Based on the best 
available information, the following actions are unlikely to result in 
a violation of section 9, if these activities are carried out in 
accordance with existing regulations and permit requirements; this list 
is not comprehensive. As identified in the SSA report, restoration 
actions are essential for conservation of the lesser prairie-chicken. 
Restoration actions will not constitute a violation of section 9 as 
those actions are implemented on lands that are not currently lesser 
prairie-chicken habitat. These restoration actions include:
    (1) Planting previously tilled or no till croplands to grasses;
    (2) Removal of nonnative or invasive trees and shrubs, not 
including shinnery oak or sand sagebrush; and
    (3) Removal of existing infrastructure including oil and gas 
infrastructure, electrical transmission and distribution lines, 
windmills, existing fences, and other anthropogenic features impacting 
the landscape.
    Based on the best available information, the following activities 
may potentially result in a violation of section 9 of the Act in the 
southern DPS of the lesser prairie-chicken if they are not authorized 
in accordance with applicable law; 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. 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 
the direct conversion of native shrub or herbaceous vegetation to 
another land use.
    (3) Actions that would result in sustained alteration of preferred 
vegetative characteristics of lesser prairie-chicken habitat, 
particularly those actions that would cause a reduction or loss in the 
native invertebrate community within those habitats or alterations to 
vegetative composition and structure. Such activities could include, 
but are not limited to, incompatible 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, communication towers, buildings, 
infrastructure to support energy development, roads, and other 
anthropogenic features; motorized and nonmotorized recreational use; 
and activities such as well drilling, operation, and maintenance, which 
would entail significant human presence, noise, and infrastructure.
    (5) Actions, intentional or otherwise, that would result in the 
destruction of eggs or active nests or cause mortality or injury to 
chicks, juveniles, or adult lesser prairie-chickens.
    Questions regarding whether specific activities would constitute a 
violation of section 9 of the Act in regards to the Southern DPS of the 
lesser prairie-chicken should be directed to the Arlington Ecological 
Services Field Office (see FOR FURTHER INFORMATION CONTACT).

II. Proposed Rule Issued Under Section 4(d) of the Act for the Northern 
DPS of the Lesser Prairie-Chicken

Background

    Section 4(d) of the Act contains two sentences. The first sentence 
states that the ``Secretary shall issue such regulations as he deems 
necessary and advisable to provide for the conservation'' of species 
listed as threatened. The U.S. Supreme Court has noted that statutory 
language like ``necessary and advisable'' demonstrates a large degree 
of deference to the agency (see Webster v. Doe, 486 U.S. 592 (1988)). 
Conservation is defined in the Act to mean ``the use of all methods and 
procedures which are necessary to bring any endangered species or 
threatened species to the point at which the measures provided pursuant 
to [the Act] are no longer necessary.'' Additionally, the second 
sentence of section 4(d) of the Act states that the Secretary ``may by 
regulation prohibit with respect to any threatened species any act 
prohibited under section 9(a)(1), in the case of fish or wildlife, or 
section 9(a)(2), in the case of plants.'' Thus, the combination of the 
two sentences of section 4(d) provides the Secretary with wide latitude 
of discretion to select and promulgate appropriate regulations tailored 
to the specific conservation needs of the threatened species. The 
second sentence grants particularly broad discretion to the Service 
when adopting the prohibitions under section 9.
    The courts have recognized the extent of the Secretary's discretion 
under this standard to develop rules that are appropriate for the 
conservation of a species. For example, courts have upheld rules 
developed under section 4(d) as a valid exercise of agency authority 
where they prohibited take of threatened wildlife, or include a limited 
taking prohibition (see Alsea Valley Alliance v. Lautenbacher, 2007 
U.S. Dist. Lexis 60203 (D. Or. 2007); Washington Environmental Council 
v. National Marine Fisheries Service, 2002 U.S. Dist. Lexis 5432 (W.D. 
Wash. 2002)). Courts have also upheld 4(d) rules that do not address 
all of the threats a species faces (see State of

[[Page 29475]]

Louisiana v. Verity, 853 F.2d 322 (5th Cir. 1988)). As noted in the 
legislative history when the Act was initially enacted, ``once an 
animal is on the threatened list, the Secretary has an almost infinite 
number of options available to him with regard to the permitted 
activities for those species. He may, for example, permit taking, but 
not importation of such species, or he may choose to forbid both taking 
and importation but allow the transportation of such species'' (H.R. 
Rep. No. 412, 93rd Cong., 1st Sess. 1973).
    Exercising this authority under section 4(d), we have developed a 
proposed rule that is designed to address the specific threats and 
conservation needs of the Northern DPS of the lesser prairie-chicken. 
Although the statute does not require us to make a ``necessary and 
advisable'' finding with respect to the adoption of specific 
prohibitions under section 9, we find that this rule as a whole 
satisfies the requirement in section 4(d) of the Act to issue 
regulations deemed necessary and advisable to provide for the 
conservation of the Northern DPS of the lesser prairie-chicken. As 
discussed above under Summary of Biological Status and Threats, we have 
concluded that the Northern DPS of the lesser prairie-chicken is likely 
to become in danger of extinction within the foreseeable future 
primarily due to threats associated with habitat loss, fragmentation, 
and degradation. The provisions of this proposed 4(d) rule would 
promote conservation of the Northern DPS of the lesser prairie-chicken 
by encouraging management of the landscape in ways that meet the 
conservation needs of the lesser prairie-chicken and identifying the 
prohibitions needed to conserve the lesser prairie-chicken. We believe 
it is appropriate to extend the standard section 9 prohibitions for 
endangered species to the Northern DPS of the lesser prairie-chicken in 
order to conserve the species.
    While developing this proposed 4(d) rule, the Service considered 
exceptions to the standard section 9 prohibitions for endangered 
species that would facilitate essential conservation actions needed for 
the Northern DPS. We consider essential conservation efforts to include 
restoration actions, utilization of prescribed fire, and compatible 
grazing management as the primary essential conservation actions needed 
to conserve the lesser prairie-chicken.
    For the purposes of this rule and our SSA analysis we consider 
restoration actions to be actions that convert areas that are otherwise 
not habitat for lesser prairie-chickens to areas which are lesser 
prairie-chicken habitat. These actions are essential for the species as 
this is the only way to offset habitat loss and fragmentation. For the 
lesser prairie-chicken, the primary restoration actions consist of 
woody vegetation removal in and adjacent to grasslands (this does not 
include the removal of sand shinnery oak (specifically, Quercus 
havardii species) or sand sagebrush (specifically, Artemisia filifolia 
species)), removal of existing anthropogenic features (such as existing 
energy infrastructure, roads, fences, windmills, and other 
anthropogenic features), and converting cropland to grassland. We have 
determined that an exception under this 4(d) rule is not needed for 
these restoration actions as they occur on lands already impacted or 
altered in ways that they no longer represent lesser prairie-chicken 
habitat and thus there is no potential for a section 9 violation.
    We also considered the value provided by the implementation of 
prescribed fire on the landscape. Prior to extensive Euro-American 
settlement, frequent fires helped confine trees like eastern red cedar 
to river and stream drainages and rocky outcroppings. However, 
settlement of the Southern Great Plains altered the historical 
ecological context and disturbance regimes. 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 that helped to maintain 
prairie habitat for lesser prairie-chicken (Collins 1992, pp. 2003-
2005; Fuhlendorf and Smeins 1999, pp. 732, 737).
    Following Euro-American settlement, fire suppression allowed trees, 
such as eastern red cedar, to begin invading or encroaching upon 
neighboring grasslands. Implementation of prescribed fire is often the 
best method to control or preclude tree invasion of grasslands. 
However, to some landowners and land managers, burning of grassland can 
be perceived as unnecessary for meeting their management goals, costly 
and burdensome to enact, undesirable for optimizing production for 
cattle, and likely to create wind erosion or ``blowouts'' in sandy 
soils. Consequently, wildfire suppression is common, and relatively 
little prescribed burning occurs on private land. Often, prescribed 
fire is employed only after significant tree invasion has already 
occurred and landowners consider forage production for cattle to have 
diminished. Preclusion of woody vegetation encroachment on grasslands 
of the southern Great Plains using fire requires implementing fire at a 
frequency that mimics historical fire frequencies of 2-14 years 
(Guyette et al. 2012, p. 330) and thus further limits the number of 
landowners implementing fire in a manner that would truly preclude 
future encroachment. We have determined that there is a potential for 
short-term adverse impacts, but we want to encourage the use of 
prescribed fire on the landscape; thus, we provide an exception for 
this action below.
    Finally, we considered the need for compatibly managed grazing 
activities that result in the vegetation structure and composition 
needed to support the lesser prairie-chicken. The habitat needs for the 
lesser prairie-chicken vary across the range, and grazing can affect 
these habitats in different ways. It is important that grazing be 
managed at a given site to account for a variety of factors specific to 
the local ecological site including past management, soils, 
precipitation and other factors. This management will ensure that the 
resulting vegetative composition and structure will support the lesser 
prairie-chicken. Grazing management that alters the vegetation 
community to a point where the composition and structure are no longer 
suitable for lesser prairie-chicken can contribute to habitat loss and 
fragmentation within the landscape, even though these areas may remain 
as prairie or grassland. Livestock grazing, however, is not inherently 
detrimental to the lesser prairie-chicken provided that grazing 
management results in a plant community with species and structural 
diversity suitable for the lesser prairie-chicken. When livestock 
grazing is managed compatibly, it can be an invaluable tool necessary 
for managing healthy grasslands benefiting the lesser prairie-chicken.
    While developing this proposed 4(d) rule, we found that determining 
how to manage grazing in a manner compatible with the Northern DPS of 
the lesser prairie chicken is highly site specific based on conditions 
at the local level; thus, broad determinations within this proposed 
4(d) rule would not be beneficial to the species or local land 
managers. While the 4(d) rule was one approach considered to promote 
conservation of the Northern DPS of the lesser prairie-chicken by 
encouraging management of grassland landscapes in ways that support 
both long-term viability of livestock enterprises, and concurrent 
conservation of lesser prairie-chicken, we determined that other 
mechanisms would be more appropriate to support this action. Besides a 
4(d) rule, other mechanisms supporting conservation opportunities

[[Page 29476]]

exist in other portions of the Endangered Species Act and our policies, 
including under Federal Agency Actions and Consultations (section 7), 
Permits (section 10), and Conservation Banking. We recognize the value 
of compatibly managed grazing for the lesser prairie-chicken, and we 
look forward to working with our partners and local land managers to 
ensure there are viable conservation options that provide regulatory 
coverage for interested landowners.
    The provisions of this proposed rule are one of many tools that we 
would use to promote the conservation of the Northern DPS of the lesser 
prairie-chicken. This proposed 4(d) rule would apply only if and when 
we make final the listing of the Northern DPS of the lesser prairie-
chicken as a threatened species.

Provisions of the Proposed 4(d) Rule

    This proposed 4(d) rule would provide for the conservation of the 
Northern DPS of the lesser prairie-chicken by prohibiting the following 
activities, except as otherwise authorized or permitted: Importing or 
exporting; take; possession and other acts with unlawfully taken 
specimens; delivering, receiving, transporting, or shipping in 
interstate or foreign commerce in the course of commercial activity; or 
selling or offering for sale in interstate or foreign commerce. We also 
include the following two exceptions to these prohibitions, which along 
with the prohibitions, are set forth under Proposed Regulation 
Promulgation:
    (1) Continuation of routine agricultural practices on existing 
cultivated lands.
    This proposed 4(d) rule provides that take of the lesser prairie-
chicken will not be prohibited provided the take is incidental to 
activities that are conducted during the continuation of routine 
agricultural practices, as specified below, on cultivated lands that 
are in row crop, seed-drilled untilled crop, hay, or forage production. 
These lands must meet the definition of cropland as defined in 7 CFR 
718.2, and, in addition, must have been cultivated, meaning tilled, 
planted, or harvested, within the 5 years preceding the proposed 
routine agricultural practice that may otherwise result in take. Thus, 
this provision does not include take coverage for any new conversion of 
grasslands into agriculture.
    Lesser prairie-chickens travel from native rangeland and CRP lands, 
which provide cover types that support lesser prairie-chicken nesting 
and brood-rearing, to forage within cultivated fields supporting small 
grains, alfalfa, and hay production. Lesser prairie-chickens also 
maintain lek sites within these cultivated areas, and they may be 
present during farming operations. Thus, existing cultivated lands, 
although not a native habitat type, may provide food resources for 
lesser prairie-chickens.
    Routine agricultural activities covered by this provision include:
    (a) Plowing, drilling, disking, mowing, or other mechanical 
manipulation and management of lands.
    (b) Routine activities in direct support of cultivated agriculture, 
including replacement, upgrades, maintenance, and operation of existing 
infrastructure such as buildings, irrigation conveyance structures, 
fences, and roads.
    (c) Use of chemicals in direct support of cultivated agriculture 
when done in accordance with label recommendations.
    We do not view regulating these activities as necessary and 
advisable for the conservation of the lesser prairie-chicken as, while 
there may be limited use for foraging and lekking sites, these lands do 
not have the ability to support the complete life-history needs of the 
species and thus are not considered habitat. We are proposing that none 
of the provisions in 50 CFR 17.31 would apply to actions that result 
from activities associated with the continuation of routine 
agricultural practices, as specified above, on existing cultivated 
lands that are in row crop, seed-drilled untilled crop, hay, or forage 
production. These lands must meet the definition of cropland as defined 
in 7 CFR 718.2, and, in addition, must have been cultivated, meaning 
tilled, planted, or harvested, within the previous 5 years.
    (2) Implementation of prescribed fire for the purposes of grassland 
management.
    This proposed 4(d) rule provides that take of the lesser prairie-
chicken will not be prohibited provided the take is incidental to 
activities that are conducted during the implementation of prescribed 
fire, as specified below, for the purpose of grassland and shrubland 
management.
    As discussed in the Background section of this proposed 4(d) rule, 
fire plays an essential role in maintaining healthy grasslands and 
shrublands, preventing woody vegetation encroachment, and encouraging 
the structural and species diversity of the plant community required by 
the lesser prairie-chicken. The intensity, scale, and frequency of fire 
regimes in the southern Great Plains has been drastically altered due 
to human suppression of wildfire resulting in widespread degradation 
and loss of grasslands. While fire plays an important role, potential 
exists for some short-term negative impacts to the lesser prairie-
chicken while implementing prescribed fire. The potential impacts 
depend upon what time of the year the fire occurs, extent of habitat 
burned and burn severity including, but are not limited to, disturbance 
of individuals, destruction of nests, and impacts to available cover 
for nesting and concealment from predators.
    Prescribed fire activities covered by this provision include:
    (a) Construction and maintenance of fuel breaks.
    (b) Planning needed for application of prescribed fire.
    (c) Implementation of the fire and all associated actions.
    (d) Any necessary monitoring and followup actions.
    Implementation of prescribed fire is essential to managing for 
healthy grasslands and shrublands, but currently use of prescribed fire 
is minimal or restricted to frequent use in small local areas within 
the range of the lesser prairie-chicken. While prescribed fire has the 
potential for some limited negative short-term effects on the lesser 
prairie-chicken, we have concluded that the long-term benefits of 
implementing prescribed fire drastically outweigh the short-term 
negative effects. Furthermore, as discussed in the background section 
of this proposed 4(d) rule, fire is a necessary component for the 
management and maintenance of healthy grassland for the lesser prairie-
chicken. We are proposing that none of the provisions in 50 CFR 17.31 
would apply to the implementation of prescribed fire as discussed 
above.
    As discussed above under Summary of Biological Status and Threats, 
threats including habitat loss, fragmentation, and degradation are 
affecting the status of the Northern DPS of the lesser prairie-chicken. 
A range of activities have the potential to affect the Northern DPS of 
the lesser prairie-chicken, including actions that would result in the 
unauthorized destruction or alteration of the species' habitat. 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; actions that would result in the long-
term alteration of preferred vegetative characteristics of lesser 
prairie-chicken habitat, particularly those actions that would cause a 
reduction or loss in the native

[[Page 29477]]

invertebrate community within those habitats.
    Such activities could include, but are not limited to, incompatible 
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; and 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, communication towers, buildings, infrastructure to support 
energy development, roads, and other anthropogenic features; motorized 
and nonmotorized recreational use; and activities such as well 
drilling, operation, and maintenance, which would entail significant 
human presence, noise, and infrastructure; and actions, intentional or 
otherwise, that would result in the destruction of eggs or active nests 
or cause mortality or injury to chicks, juveniles, or adult lesser 
prairie-chickens. Regulating these activities would slow the rate of 
habitat loss, fragmentation, and degradation and decrease synergistic, 
negative effects from other threats.
    Under the Act, ``take'' means to harass, harm, pursue, hunt, shoot, 
wound, kill, trap, capture, or collect, or to attempt to engage in any 
such conduct. Some of these provisions have been further defined in 
regulation at 50 CFR 17.3. Take can result knowingly or otherwise, by 
direct and indirect impacts, intentionally or incidentally. Regulating 
take would help slow the rate of habitat loss, fragmentation, and 
degradation and decrease synergistic, negative effects from other 
threats.
    We may issue permits to carry out otherwise prohibited activities, 
including those described above, involving threatened wildlife under 
certain circumstances. Regulations governing permits are codified at 50 
CFR 17.32. With regard to threatened wildlife, a permit may be issued 
for the following purposes: For scientific purposes, to enhance 
propagation or survival, for economic hardship, for zoological 
exhibition, for educational purposes, for incidental taking, or for 
special purposes consistent with the purposes of the Act. There are 
also certain statutory exemptions from the prohibitions, which are 
found in sections 9 and 10 of the Act.
    We recognize the special and unique relationship with our State 
natural resource agency partners in contributing to conservation of 
listed species. State agencies often possess scientific data and 
valuable expertise on the status and distribution of endangered, 
threatened, and candidate species of wildlife and plants. State 
agencies, because of their authorities and their close working 
relationships with local governments and landowners, are in a unique 
position to assist the Services in implementing all aspects of the Act. 
In this regard, section 6 of the Act provides that the Services shall 
cooperate to the maximum extent practicable with the States in carrying 
out programs authorized by the Act. Therefore, any qualified employee 
or agent of a State conservation agency that is a party to a 
cooperative agreement with the Service in accordance with section 6(c) 
of the Act, who is designated by his or her agency for such purposes, 
would be able to conduct activities designed to conserve the Northern 
DPS of the lesser prairie-chicken that may result in otherwise 
prohibited take without additional authorization.
    Nothing in this proposed 4(d) rule would change in any way the 
recovery planning provisions of section 4(f) of the Act, the 
consultation requirements under section 7 of the Act, or the ability of 
the Service to enter into partnerships for the management and 
protection of the Northern DPS of the lesser prairie-chicken. However, 
interagency cooperation may be further streamlined through planned 
programmatic consultations for the species between Federal agencies and 
the Service, where appropriate. We ask the public, particularly State 
agencies and other interested stakeholders that may be affected by the 
proposed 4(d) rule, to provide comments and suggestions regarding 
additional guidance and methods that the Service could provide or use, 
respectively, to streamline the implementation of this proposed 4(d) 
rule (see Information Requested, above).

III. Critical Habitat

Background

    Critical habitat is defined in section 3 of the Act as:
    (1) 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
    (a) Essential to the conservation of the species, and
    (b) Which may require special management considerations or 
protection; and
    (2) 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.
    Our regulations at 50 CFR 424.02 define the geographical area 
occupied by the species as an area that may generally be delineated 
around species' occurrences, as determined by the Secretary (i.e., 
range). Such areas may include those areas used throughout all or part 
of the species' life cycle, even if not used on a regular basis (e.g., 
migratory corridors, seasonal habitats, and habitats used periodically, 
but not solely by vagrant individuals).
    Conservation, as defined under section 3 of the Act, means to use 
and the use of all methods and procedures that are 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 otherwise 
relieved, may include regulated taking.
    Critical habitat receives protection under section 7 of the Act 
through the requirement that Federal agencies ensure, 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 affect 
land ownership or establish a refuge, wilderness, reserve, preserve, or 
other conservation area. Designation also does not allow the government 
or public to access private lands, nor does designation require 
implementation of restoration, recovery, or enhancement measures by 
non-Federal landowners. Where a landowner requests Federal agency 
funding or authorization for an action that may affect a listed species 
or critical habitat, the Federal agency would be required to consult 
with the Service under section 7(a)(2) of the Act. However, even if the 
Service were to conclude that the proposed activity would result in 
destruction or adverse modification of the critical habitat, the 
Federal action agency and the landowner are not required to abandon the 
proposed activity, or to restore or recover the species; instead, they 
must 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

[[Page 29478]]

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 or biological features that occur in specific occupied areas, 
we focus on the specific features that are essential to support the 
life-history needs of the species, including, but not limited to, water 
characteristics, soil type, geological features, prey, vegetation, 
symbiotic species, or other features. A feature may be a single habitat 
characteristic or a more complex combination of habitat 
characteristics. Features may include habitat characteristics that 
support ephemeral or dynamic habitat conditions. Features may also be 
expressed in terms relating to principles of conservation biology, such 
as patch size, distribution distances, and connectivity.
    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. When designating critical habitat, the Secretary will first 
evaluate areas occupied by the species. The Secretary will only 
consider unoccupied areas to be essential where a critical habitat 
designation limited to geographical areas occupied by the species would 
be inadequate to ensure the conservation of the species. In addition, 
for an unoccupied area to be considered essential, the Secretary must 
determine that there is a reasonable certainty both that the area will 
contribute to the conservation of the species and that the area 
contains one or more of those physical or biological features essential 
to the conservation of the species.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific 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 should be designated as 
critical habitat, our primary source of information is generally the 
information from the SSA report and information developed during the 
listing process for the species. Additional information sources may 
include any generalized conservation strategy, criteria, or outline 
that may have been developed for the species; the recovery plan for the 
species; articles in peer-reviewed journals; conservation plans 
developed by States and counties; scientific status surveys and 
studies; biological assessments; other unpublished materials; or 
experts' opinions or personal knowledge.
    Habitat is dynamic, and species may move from one area to another 
over time. 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. 
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 ensure their actions are not likely to 
jeopardize the continued existence of any endangered or threatened 
species; and (3) the prohibitions found in section 9 of the Act. 
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, habitat conservation plans, 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 shall designate critical habitat at the 
time the species is determined to be an endangered or threatened 
species. Our regulations (50 CFR 424.12(a)(1)) state that the Secretary 
may, but is not required to, determine that a designation would not be 
prudent in the following circumstances:
    (i) The species is threatened by taking or other human activity and 
identification of critical habitat can be expected to increase the 
degree of such threat to the species;
    (ii) The present or threatened destruction, modification, or 
curtailment of a species' habitat or range is not a threat to the 
species, or threats to the species' habitat stem solely from causes 
that cannot be addressed through management actions resulting from 
consultations under section 7(a)(2) of the Act;
    (iii) Areas within the jurisdiction of the United States provide no 
more than negligible conservation value, if any, for a species 
occurring primarily outside the jurisdiction of the United States;
    (iv) No areas meet the definition of critical habitat; or
    (v) The Secretary otherwise determines that designation of critical 
habitat would not be prudent based on the best scientific data 
available.
    As discussed earlier in this document, there is currently no 
imminent threat of collection or vandalism identified under Factor B 
for either the Northern DPS or the Southern DPS of the lesser prairie-
chicken, and identification and mapping of critical habitat is not 
expected to initiate any such threat. In our SSA report and proposed 
listing determination for both the Northern and Southern DPSs, we 
determined that the present or threatened destruction, modification, or 
curtailment of habitat or range is a threat to the two DPSs and that 
the threat in some way can be addressed by section 7(a)(2) consultation 
measures. The two DPSs occur wholly in the jurisdiction of the United 
States, and we are able to identify areas that meet the definition of 
critical habitat. Therefore, because none of the circumstances 
enumerated in our regulations at 50 CFR 424.12(a)(1) have been met and 
because there are no other circumstances the Secretary has

[[Page 29479]]

identified for which this designation of critical habitat would be not 
prudent, we have determined that the designation of critical habitat is 
prudent for both DPSs of 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 
Northern DPS and the Southern DPS of lesser prairie-chicken 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) Data sufficient to perform required analyses are lacking, or
    (ii) The biological needs of the species are not sufficiently well 
known to identify any area that meets the definition of ``critical 
habitat.''
    We reviewed the available information pertaining to the biological 
needs of the species and habitat characteristics where this species is 
located and data that would be needed to perform other required 
analyses. A careful assessment of the economic impacts that may occur 
due to a critical habitat designation is not yet complete, and we are 
in the process of working with the States and other partners in 
acquiring the complex information needed to perform that assessment. 
Because the information sufficient to perform a required analysis of 
the impacts of the designation is lacking, we therefore conclude that 
the designation of critical habitat for both the Southern DPS and the 
Northern DPS of the lesser prairie-chicken to be not determinable at 
this time. The Act allows the Service an additional year to publish a 
critical habitat designation that is not determinable at the time of 
listing (16 U.S.C. 1533(b)(6)(C)(ii)).

Public Hearings

    We have scheduled two public informational meeting with public 
hearings on this proposed rule for the lesser prairie-chicken. We will 
hold the public informational meetings and public hearings on the dates 
and at the times listed above under Public informational meeting and 
public hearing in DATES. We are holding the public informational 
meetings and public hearings via the Zoom online video platform and via 
teleconference so that participants can attend remotely. For security 
purposes, registration is required. To listen and view the meeting and 
hearing via Zoom, listen to the meeting and hearing by telephone, or 
provide oral public comments at the public hearing by Zoom or 
telephone, you must register. For information on how to register, or if 
you encounter problems joining Zoom the day of the meeting, visit 
https://www.fws.gov/southwest/. Registrants will receive the Zoom link 
and the telephone number for the public informational meetings and 
public hearings. If applicable, interested members of the public not 
familiar with the Zoom platform should view the Zoom video tutorials 
(https://support.zoom.us/hc/en-us/articles/206618765-Zoom-video-tutorials) prior to the public informational meetings and public 
hearings.
    The public hearings will provide interested parties an opportunity 
to present verbal testimony (formal, oral comments) regarding this 
proposed rule. While the public informational meetings will be an 
opportunity for dialogue with the Service, the public hearings are not: 
They are a forum for accepting formal verbal testimony. In the event 
there is a large attendance, the time allotted for oral statements may 
be limited. Therefore, anyone wishing to make an oral statement at the 
public hearings for the record is encouraged to provide a prepared 
written copy of their statement to us through the Federal eRulemaking 
Portal, or U.S. mail (see ADDRESSES, above). There are no limits on the 
length of written comments submitted to us. Anyone wishing to make an 
oral statement at the public hearings must register before the hearing 
(https://www.fws.gov/southwest/). The use of a virtual public hearing 
is consistent with our regulations at 50 CFR 424.16(c)(3).

Required Determinations

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:
    (1) Be logically organized;
    (2) Use the active voice to address readers directly;
    (3) Use clear language rather than jargon;
    (4) Be divided into short sections and sentences; and
    (5) 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 ADDRESSES. 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.
National Environmental Policy Act (42 U.S.C. 4321 et seq.)
    We have determined that environmental assessments and environmental 
impact statements, as defined under the authority of the National 
Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.), need not be 
prepared in connection with regulations adopted pursuant to section 
4(a) 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. We solicited information from all of 
the Tribes within the entire range of the lesser prairie-chicken to 
inform the development of the SSA report, and notified Tribes of our 
upcoming proposed listing determination. We also provided these Tribes 
the opportunity to review a draft of the SSA report and provide input 
prior to making our proposed determination on the status of the lesser 
prairie-chicken but did not receive any responses. We will continue to 
coordinate with affected Tribes throughout the listing process as 
appropriate.

References Cited

    A complete list of references cited in this rulemaking is available 
on the internet at http://www.regulations.gov and upon request from the 
Arlington Ecological Services Field Office (see FOR FURTHER INFORMATION 
CONTACT).

Authors

    The primary authors of this proposed rule are the staff members of 
the Fish

[[Page 29480]]

and Wildlife Service's Species Assessment Team and the Arlington 
Ecological Services Field Office.

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--ENDANGERED AND THREATENED WILDLIFE AND PLANTS

0
1. The authority citation for part 17 continues to read as follows:

    Authority:  16 U.S.C. 1361-1407; 1531-1544; and 4201-4245, 
unless otherwise noted.
0
2. In Sec.  17.11(h) amend the table by adding an entry for ``Prairie-
chicken, lesser [Northern DPS]'' and an entry for ``Prairie-chicken, 
lesser [Southern DPS]'' in alphabetical order under Birds to read as 
follows:


Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

----------------------------------------------------------------------------------------------------------------
                                                                                              Listing citations
           Common name                Scientific name        Where listed         Status       and  applicable
                                                                                                    rules
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------
              Birds
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
Prairie-chicken, lesser [Northern  Tympanuchus           U.S.A. (All lesser              T   [Federal Register
 DPS].                              pallidicinctus.       prairie-chickens                    citation when
                                                          north of a line                     published as a
                                                          starting at 37.9868                 final rule];
                                                          N, 105.0133 W, and                 50 CFR
                                                          ending at 31.7351                   17.41(k).\4d\
                                                          N, 98.3773 W,
                                                          NAD83; see map at
                                                          Sec.   17.41(k)).
Prairie-chicken, lesser [Southern  Tympanuchus           U.S.A. (All lesser              E   [Federal Register
 DPS].                              pallidicinctus.       prairie-chickens                    citation when
                                                          north of a line                     published as a
                                                          starting at 37.9868                 final rule].
                                                          N, 105.0133 W, and
                                                          ending at 31.7351
                                                          N, 98.3773 W,
                                                          NAD83; see map at
                                                          Sec.   17.41(k)).
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------

0
3. Amend Sec.  17.41 by adding paragraph (k) to read as follows:


Sec.  17.41  Special rules--birds.

* * * * *
    (k) Lesser prairie-chicken (Tympanuchus pallidicinctus), Northern 
Distinct Population Segment (DPS). The Northern DPS of the lesser 
prairie-chicken pertains to lesser prairie-chickens found northeast of 
a line starting in Colorado at 37.9868 N, 105.0133 W, going through 
northeastern New Mexico, and ending in Texas at 31.7351 N, 98.3773 W, 
NAD83, as shown in the map:
BILLING CODE 4333-15-P

[[Page 29481]]

[GRAPHIC] [TIFF OMITTED] TP01JN21.023

    (1) Prohibitions. The following prohibitions that apply to 
endangered wildlife also apply to the Northern DPS of the lesser 
prairie-chicken. Except as provided under paragraph (k)(2) of this 
section and Sec. Sec.  17.4 and 17.5, it is unlawful for any person 
subject to the jurisdiction of the United States to commit, to attempt 
to commit, to solicit another to commit, or cause to be committed, any 
of the following acts in regard to this species:
    (i) Import or export, as set forth at Sec.  17.21(b) for endangered 
wildlife.
    (ii) Take, as set forth at Sec.  17.21(c)(1) for endangered 
wildlife.
    (iii) Possession and other acts with unlawfully taken specimens, as 
set forth at Sec.  17.21(d)(1) for endangered wildlife.
    (iv) Interstate or foreign commerce in the course of a commercial 
activity, as set forth at Sec.  17.21(e) for endangered wildlife.
    (v) Sale or offer for sale, as set forth at Sec.  17.21(f) for 
endangered wildlife.
    (2) Exceptions from prohibitions. In regard to this species, you 
may:
    (i) Conduct activities as authorized by a permit under Sec.  17.32.
    (ii) Take, as set forth at Sec.  17.21(c)(2) through (c)(4) for 
endangered wildlife.
    (iii) Take as set forth at Sec.  17.31(b).
    (iv) Take incidental to an otherwise lawful activity caused by:
    (A) Continuation of routine agricultural practices on existing 
cultivated lands, including:

[[Page 29482]]

    (1) Plowing, drilling, disking, mowing, or other mechanical 
manipulation and management of lands;
    (2) Routine activities in direct support of cultivated agriculture, 
including replacement, upgrades, maintenance, and operation of existing 
infrastructure such as buildings, irrigation conveyance structures, 
fences, and roads; and
    (3) Use of chemicals in direct support of cultivated agriculture 
when done in accordance with label recommendations.
    (B) Implementation of prescribed fire for the purposes of grassland 
management, including:
    (1) Construction and maintenance of fuel breaks;
    (2) Planning needed for application of prescribed fire;
    (3) Implementation of the fire and all associated actions; and
    (4) Any necessary monitoring and followup actions.
    (v) Possess and engage in other acts with unlawfully taken 
wildlife, as set forth at Sec.  17.21(d)(2) for endangered wildlife.

Martha Williams,
Principal Deputy Director, Exercising the Delegated Authority of the 
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2021-11442 Filed 5-28-21; 8:45 am]
BILLING CODE 4333-15-C`