Gray Wolves Under the
Endangered Species Act (ESA):
Distinct Population Segments
and Experimental Populations
Kristina Alexander
Legislative Attorney
M. Lynne Corn
Specialist in Natural Resources Policy
August 17, 2011
Congressional Research Service
7-5700
www.crs.gov
RL34238
CRS Report for Congress
Pr
epared for Members and Committees of Congress
Gray Wolves Under the Endangered Species Act
Summary
The wolf was nearly eradicated from the lower 48 states in the first half of the 20th century. In
1974 U.S. Fish and Wildlife Service (FWS) placed the gray wolf subspecies, the eastern timber
wolf and the northern Rocky Mountain wolf, on the Endangered Species Act’s (ESA) first list of
endangered species. In 1978 FWS replaced the subspecies listings by listing the gray wolf (Canis
lupus) species as endangered in all of the conterminous 48 states except Minnesota, where FWS
listed it as threatened. In 2011 FWS found that this listing was in error; that more targeted
regional units were appropriate for wolves (notably in the Southwest and Pacific Northwest); that
a newly recognized species, the eastern wolf (Canis lycaon), not the gray wolf, occupied the
Northeast; and that all or parts of 29 eastern states should be removed from the gray wolf’s
historic range.
With the exception of experimental populations (Ex Pops) of gray wolves that FWS established
in order to reintroduce wolves to selected areas, protections for the gray wolf have diminished as
wolf populations have increased in areas such as the Northern Rocky Mountains. The use of
distinct population segments (DPSs), a term created in the 1978 ESA amendments, has played a
role in reduced protection. Through DPSs, vertebrate species may be divided into distinct groups,
based on geography and genetic distinctions for listing purposes.
Ex Pops of wolves were reintroduced in three regions of the United States in the 1990s: Central
Idaho, Yellowstone, and the Blue Range of Arizona and New Mexico. The Ex Pops in Central
Idaho and Yellowstone have grown to over 1,650 wolves as of December 31, 2010, while the
Mexican gray wolf population of the Blue Range has not surpassed 59 wolves, and as of January
2011 totaled 50.
ESA protection for wolf DPSs has varied since the first DPSs, Western, Eastern, and
Southwestern, were proposed in 2003. Each effort by FWS to delist the wolf or designate a DPS
has been rejected by a court or settled by the agency. Most recently, the April 2009 rules that had
established and then delisted DPSs in the Western Great Lakes and the Northern Rockies were
nullified as a result of litigation. As a consequence, the Northern Rockies wolves resumed their
Ex Pop status, meaning they were treated as threatened in most circumstances but were
endangered outside of the Ex Pop boundaries. Wolves in the rest of the lower 48 states were again
endangered, with the exception of Minnesota wolves, which were threatened.
The April 2009 rule for the Northern Rockies was the topic of legislation in April 2011, when
Congress took the unusual step of directing FWS to delist an endangered species. Section 1713 of
P.L. 112-10 required FWS to reissue the 2009 Northern Rockies DPS rule. FWS’s reissuance of
that rule on May 5, 2011, ended federal protection of the gray wolf in Montana, Idaho, eastern
Washington, eastern Oregon, and north-central Utah, but kept the wolf as a listed species in the
remainder of the lower 48 states. Also on May 5, 2011, FWS proposed designating a DPS in the
Western Great Lakes area and delisting those gray wolves.
This report analyzes the ESA as it applies to gray wolf wolves and, in particular, to their treatment
as Ex Pops and DPSs.
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Contents
Introduction...................................................................................................................................... 1
Wolf Populations: A Taxonomic View............................................................................................. 1
The Endangered Species Act ........................................................................................................... 3
Listing a Species as Endangered or Threatened ........................................................................ 3
Experimental Populations.......................................................................................................... 4
Distinct Population Segments.................................................................................................... 4
Regulatory History of DPSs................................................................................................ 5
Agency Use of DPSs ........................................................................................................... 6
Gray Wolf Listing ............................................................................................................................ 8
Gray Wolf Recovery Plans ........................................................................................................ 8
Experimental Populations of Gray Wolves...................................................................................... 9
Yellowstone and Central Idaho Ex Pops.................................................................................... 9
Yellowstone and Central Idaho Ex Pop Litigation ............................................................ 10
Blue Range Ex Pop.................................................................................................................. 12
Blue Range Litigation ....................................................................................................... 12
Gray Wolf DPSs............................................................................................................................. 12
2003 Western, Eastern, and Southwestern DPSs..................................................................... 13
Western, Eastern, and Southwestern DPS Litigation ........................................................ 13
2007 Western Great Lakes DPS and 2008 Northern Rocky Mountain DPS ........................... 13
2007 Western Great Lakes DPS Litigation ....................................................................... 14
2008 Northern Rocky Mountain DPS Litigation .............................................................. 14
2009 Western Great Lakes and Northern Rocky Mountain DPSs........................................... 15
2009 Western Great Lakes DPS Litigation ....................................................................... 16
2009 Northern Rocky Mountain DPS Litigation .............................................................. 16
Comparative Wolf Density Before the Reissuance of the April 2009 Rule............................. 18
2011 Regulatory and Legislative Activity ..................................................................................... 19
Legislation Directing Delisting of Northern Rocky Mountain DPS: P.L. 112-10, §
1713...................................................................................................................................... 19
Proposed Gray Wolf Legislation ............................................................................................. 19
Proposed Rulemaking: Redefining Populations, Species, and Range..................................... 20
Proposed New Species: The Eastern Wolf ........................................................................ 21
Other Status Reviews ........................................................................................................ 22
Proposed Alteration of Historic Range.............................................................................. 23
Interpretation of Significant Portion of Its Range ............................................................. 23
Figures
Figure 1. Reintroduction Zone of the Central Idaho Experimental Population ............................. 10
Figure 2. Reintroduction Zone of the Yellowstone Experimental Population ............................... 10
Figure 3. Northern Rocky Mountain Gray Wolf DPS Area in 2008.............................................. 15
Figure 4. Wolf Density as of 2009 ................................................................................................. 18
Figure 5. Gray Wolf Protection Proposed by 76 Federal Register 26086 ..................................... 21
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Appendixes
Appendix........................................................................................................................................ 25
Contacts
Author Contact Information........................................................................................................... 27
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Introduction
For centuries, wolf populations have been under pressure by humans. Wolves are carnivores,
feeding not only on a variety of animal species smaller than themselves, but also on very large
mammals such as bison, elk, and even moose. Wolves are able to prey on large mammals by
hunting cooperatively in packs. However, these large species are also favorite game animals for
human hunters. In addition to game animals, their prey may include livestock such as cattle and
sheep; some people perceive them as a direct threat to humans as well. These habits led to an
effort to reduce or eliminate the species. Wolves were eventually eliminated in most states in an
effort supported by the science community at the time. But coinciding roughly with the forester
Aldo Leopold’s essay, “Killing the Wolf,” in A Sand County Almanac in 1948, the view that
wolves must be eliminated began to change. Leopold wrote:
I was young then, and full of trigger-itch; I thought that because fewer wolves meant more
deer, that no wolves would mean hunters’ paradise. But after seeing the green fire die, I
sensed that neither the wolf nor the mountain agreed with such a view.... Since then I have
lived to see state after state extirpate its wolves. I have watched the face of many a newly
wolfless mountain, and seen the south-facing slopes wrinkle with a maze of new deer trails. I
have seen every edible bush and seedling browsed, first to anaemic desuetude, and then to
death.
Leopold’s somewhat poetic understanding of predator-prey interactions marked the beginning of
a new scientific view of the role of predators in ecosystems. Scientists came to agree that, in the
absence of major predators, prey populations would expand until some other factor (usually food)
limited their population growth. As seen in a variety of ecosystems, the elimination of major
predators devastated plant populations and led to serious reductions in the other species
depending on those plants for food, nesting, migration habitat, or concealment or in any species
dependent on the undisturbed ecosystem. The disappearance of wolves, eagles and other hawks,
bears, and other top carnivores in much of their former ranges contributed to the passage of the
Endangered Species Act (ESA) in 1973, and ultimately, to the re-introduction of wolves into parts
of their former range. And predictably, the conflicts over livestock and game that led to the wolf’s
near extinction a century ago re-emerged. The ensuing conflicts over wolf management are the
topic of this report.
Wolf Populations: A Taxonomic View
To protect gray wolves under the ESA, there needs to be some agreement on what a gray wolf is
scientifically. Like many large mammals, such as bears (Ursus arctos), mountain lions (Felis
concolor), and white-tailed deer (Odocoileus virginianus), gray wolves (Canis lupus) have a
complicated, even convoluted, taxonomic history. Variations in color, size, and bone structure
have led some mammalogists to designate wolves in different areas as different subspecies or
populations, whereas other experts would recognize only a single species with variability. A few
key terms are central to the taxonomic debate discussed below:
• A population is a group of “organisms of the same species that inhabit a specific
area.”
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• A species is a “naturally [occurring] population or a group of potentially
interbreeding populations that is reproductively isolated (i.e., cannot exchange
genetic material) from other such populations or groups.”
• A subspecies is a “taxonomic category that subdivides species into
morphologically distinct groups of individuals representing a step toward the
production of a new species, although they are still fully capable of interbreeding.
Subspecies are usually geographically isolated.”
• Taxon, or the plural taxa, is defined as “a grouping of organisms given a formal
taxonomic name at any rank: species, genus, family, order, class, division,
phylum, or kingdom.”1
These terms may appear clear; however, there are no simple measures to draw unequivocal
distinctions. Biologists commonly describe their colleagues as lumpers or splitters, based on their
inclinations in classifying organisms. As the names suggest, lumpers are those who tend to
minimize differences, and see one or a few species, perhaps with some variations, while splitters
tend to emphasize those differences, dividing a species into many subspecies, or populations. As
one well-known mammalogist once stated:
Splitters make very small units—their opponents say that if they can tell two animals apart,
they place them in different genera, and if they cannot tell them apart, they place them in
different species. Lumpers make large units—their opponents say that if a carnivore is
neither a dog nor a bear they call it a cat.2
For wolves, which are (or were) found in temperate and polar areas throughout the Northern
Hemisphere, some observers (splitters) would argue that there are as many as 24 subspecies in
North America and 8 in Europe and Asia.3 More recently, lumpers have had the upper hand in the
scientific community. However, that tide may be changing. In May 2011, the U.S. Fish and
Wildlife Service (FWS) proposed recognizing a third species of wolf, the eastern wolf (Canis
lycaon), in addition to the gray and red wolf.4 (See “2011 Regulatory and Legislative Activity”
below, for more on this announcement.)
This muddled state of taxonomic affairs is entirely predictable for several reasons. First, wolves
are extremely wide-ranging, both as a species and as individuals, so occasional interbreeding
among them could certainly confuse the picture. Second, the consistency of variations over time
is hard to determine, since long-range studies of long-lived species are rare. Third, evolutionary
change does not stop, and wolves are an adaptable species, as shown by their behavior and by
their presence in a tremendous variety of ecosystems.5 The debate among academic scientists also
1 All the definitions are from Henry W. Art (ed.), The Dictionary of Ecology and Environmental Science (New York:
Henry Holt and Co. 1993).
2 George Gaylord Simpson, “The Principles of Classification and the Classification of Mammals,” Bulletin of the
American Museum of Natural History, vol. 85 (1945), p. 23. Debates over the proper classification of species are not
rare, particularly for vertebrates; only the listing of a species and the need for legal clarity over what is protected and
what is not bring such debates into a practical realm.
3 See discussion, citing various authors, in L. David Mech, The Wolf: The Ecology and Behavior of an Endangered
Species, pp. 29-31 (Garden City, NY: Natural History Press 1970).
4 76 Federal Register 26086 (May 5, 2011).
5 For example, should global warming proceed and arctic snow cover diminish, will the genes for white coats diminish
in the arctic wolves? That may be likely, since more brightly colored wolves would be at a disadvantage in much of the
year and over a growing area. Natural selection would then tend to disfavor these animals and their offspring.
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has an air of informed judgment—and there is no reason to predict that the scientific debate will
end any time soon.
The Endangered Species Act
The Endangered Species Act6 (ESA or the Act) provides for the protection and conservation of
species that the FWS or the National Marine Fisheries Service identifies as threatened or
endangered.7
Listing a Species as Endangered or Threatened
Under the ESA, if FWS determines that the best scientific information available indicates that a
species is in danger of becoming extinct throughout all or a significant portion of its range, FWS
lists the species as endangered.8 If FWS determines that a species is likely to become endangered
within the foreseeable future, FWS lists the species as threatened.9 If the scientific bases
underlying a listing change, FWS may take three steps: delist the species, thereby removing it
from ESA protection; downlist it, decreasing its protection level from endangered to threatened;
or uplist it, increasing its protection level from threatened to endangered.
ESA amendments further allow FWS to list distinct population segments (DPS) within vertebrate
species for protection. FWS may also reintroduce experimental populations (Ex Pops) to areas
that the species no longer occupies within it historic range.10
The ESA prohibits taking an endangered wildlife,11 which means it is illegal to harass, harm, or
kill such species.12 FWS regulations further prohibit taking a threatened species unless special
rules are in place.13 However, the taking prohibition is not absolute and may be allowed for
threatened species, including threatened DPSs and Ex Pops that are treated as threatened. FWS
may issue Section 4(d) rules or special rules to provide customized protection that FWS deems
necessary and advisable for the species’ conservation.14 Under special rules, taking species,
including killing them, may be allowed. The special rules are promulgated in Title 50 (Part 17) of
the Code of Federal Regulations.
The ESA requires FWS to develop a recovery plan for listed species15 that will include a
description of necessary management actions, measurable criteria for when a species can be
delisted, and estimated costs to achieve this goal.
6 For a more detailed explanation of the ESA, see CRS Report RL31654, The Endangered Species Act: A Primer.
7 Because this report is about the gray wolf, discussion of ESA authority will reference only FWS, which is the Service
overseeing the wolves’ protection.
8 16 U.S.C. § 1533(b) – criteria for listing; 16 U.S.C. § 1532(6) – definition of endangered. In the event that resources
for listing are limited, FWS will list the species as “warranted but precluded” under 16 U.S.C. § 1533(b)(3)(B)(iii).
9 16 U.S.C. § 1532(20).
10 16 U.S.C. § 1539(j).
11 16 U.S.C. § 1538.
12 16 U.S.C. § 1532(19).
13 50 C.F.R. § 17.31.
14 16 U.S.C. § 1533(d).
15 16 U.S.C. § 1533(f).
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Experimental Populations
In 1982, Congress modified the ESA to allow reintroducing Ex Pops of listed species “outside the
current range of such species if the Secretary determines that such release will further the
conservation of the species.”16 Congress intended Ex Pops as a way to expand current ranges of
listed species without imposing severe restrictions of private and public land. The practice allows
introduction of a species outside its current range to restore it to its historic range.
Two criteria must be met to establish an experimental population under the law. First, the
Department of the Interior (DOI) must authorize the release of the population. Second, the
population must be “wholly separate geographically from nonexperimental populations of the
species.”17 Congress required the separation so that the introduced population could be clearly
distinguished from existing populations of the species.
Under the ESA, members of an Ex Pop generally are treated as threatened,18 and are eligible for
special rules.19 A congressional committee referred to special rules as a way to reduce public
opposition to the release of Ex Pops of predators, such as wolves:
The committee fully expects that there will be instances where the regulations allow for the
incidental take of experimental populations.... The committee also expects that, where
appropriate, the regulations could allow for the directed taking of experimental populations.
For example, the release of experimental populations of predators, such as red wolves, could
allow for the taking of these animals if depredations occur or if the release of these
populations will continue to be frustrated by public opposition.20
Section 10(j)(2)(B) of the ESA requires FWS to determine whether the Ex Pop is essential to the
continued existence of an endangered or threatened species, otherwise the Ex Pop is deemed
nonessential. Currently, there are no essential experimental populations. Critical habitat is not
designated for nonessential Ex Pops.
Examples of species with nonessential experimental populations are the Colorado pikeminnow
(or squawfish), the southern sea otter, the gray wolf (in the Southwest, central Idaho, and
Yellowstone areas), the black-footed ferret, and the whooping crane.
Distinct Population Segments
The ESA definition of species has changed since the law’s enactment. In 1973 the definition
included “any subspecies of fish or wildlife or plants and any other group of fish or wildlife of the
same species or smaller taxa in common spatial arrangement that interbreed when mature.”21 In
16 P.L. 97-304 § 6(6), 96 Stat. 1424; 16 U.S.C. § 1539(j).
17 16 U.S.C. § 1539(j). Because this appears in Section 10(j) of the Public Law enacting the ESA, P.L. 93-205, as
amended, it is sometimes referred to as ESA § 10(j).
18 16 U.S.C. § 1539(j)(2)(C). See discussion of Section 4(d) Rules, below.
19 16 U.S.C. § 1533(d).
20 1982 U.S. Code Cong. and Admin. News, at 2834.
21 P.L. 93-205, § 3(11), 87 Stat. 886.
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1978 Congress amended that definition to include the term distinct population segment (DPS),
which was limited to vertebrates.22 The change was controversial.
The General Accounting Office (GAO) (now the Government Accountability Office)
recommended limiting the definition of species to higher taxonomic categories than populations,
and excluding all distinct populations, including geographically separated populations.23 GAO
proposed the following definition: “The term ‘species’ includes any subspecies of fish, wildlife,
or plants.”24
Congress did not follow the GAO recommendation. It agreed with FWS that the service needed to
be able to adopt different management practices for different populations, based on need. A
Senate committee report discussing populations said, “the committee agrees that there may be
instances in which FWS should provide for different levels of protection for populations of the
same species,” but advised that the practice be used “sparingly and only when the biological
evidence indicates that such action is warranted.”25
Thus, Congress revised and limited the definition of species in 1978 by eliminating taxonomic
categories below subspecies from the definition, except for vertebrates.26 The revised, and still
current, definition is “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.”27 However,
the phrase distinct population segment had no meaning in the scientific community outside of the
ESA, and was not used in ESA listings by FWS for nearly two decades.
Regulatory History of DPSs
A DPS refers generally to a portion of a listed species that is separated from the rest of the species
by genetic distinction and range. The legislative history offers two examples of when the same
species should have different protection: (1) when a U.S. population of an animal is near
extinction even though another population outside the United States is more abundant; and (2)
where conclusive data have been available only for certain populations of a species and not for
the species as a whole.28
In 1996 FWS introduced its DPS policy (hereinafter referred to as “the Policy”).29 The Policy
contains the criteria that must be met for a species to be protected at the population level. First,
the population segment must be discrete. Factors considered to determine discreteness are
whether the segment is “markedly separated from other populations of the same taxon as a
22 P.L. 95-632; 16 U.S.C. § 1532(16).
23 GAO Testimony before the Subcommittee on Resource Protection, No. 108960, p. 5 (April 3, 1979).
24 GAO Testimony before the Subcommittee on Resource Protection, No. 108960, Attach. 1 (April 3, 1979).
25 S.Rept. 96-151, p. 7 (May 15, 1979). The discussion occurs after the amendment, because, according to the Senate
report, “some clarification would be useful.”
26 H.Rept. 95-1625 at 25 (September 25, 1978). Restriction to vertebrates is a severe limitation in terms of numbers of
species able to enjoy this level of protection. Insects alone outnumber all other animals by three to one. Donald J.
Borror, et al., An Introduction to the Study of Insects, p. 1. (Saunders College Publishing: New York, 5th ed. 1981).
27 16 U.S.C. § 1532(16).
28 S.Rept. 96-151, p. 7 (May 15, 1979).
29 61 Federal Register 4722 (February 7, 1996).
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consequence of physical, physiological, ecological, or behavioral factors.”30 Discreteness can also
be found if the population is delimited by international governmental boundaries. Although state
boundaries are frequently used to describe a DPS, they cannot be used under the Policy to
determine discreteness.
Next, the population segment must be found to be significant, meaning its demise would be an
important loss of genetic diversity.31 Four factors are listed in the Policy for determining a
species’ significance: (1) persistence of the segment in an ecological setting unusual or unique for
the taxon; (2) evidence that loss of the DPS would result in a significant gap in the range of the
taxon; (3) evidence that the DPS represents the only surviving natural occurrence of a taxon
within its historic range; or (4) evidence that the DPS differs markedly from other populations of
the species in its genetic characteristics. Genetic evidence may be considered but is not required.
The Policy indicates that “available scientific evidence of the discrete population segment’s
importance” will be considered in finding significance, but does not specify the best available
scientific evidence.
If a species is found to be both discrete and significant, then its status is reviewed to see whether
it is endangered or threatened. The same criteria are used for a DPS listing as for any other listing.
The determination must be based solely on the “best scientific and commercial data available.”32
According to the Policy, agency efficiency and focus were two intended benefits of DPSs. The
Policy said determining DPSs will “concentrate ... efforts toward the conservation of biological
resources at risk of extinction.”33 The Policy suggested the practice of using DPSs could help
endangered species by focusing on smaller groups:
This may allow protection and recovery of declining organisms in a more timely and less
costly manner, and on a smaller scale than the more costly and extensive efforts that might
be needed to recover an entire species or subspecies. The Services’ [FWS & the National
Marine Fisheries Service’s] ability to address local issues (without the need to list, recover,
and consult rangewide) will result in a more effective program.34
FWS has followed Congress’s admonition to apply the practice “sparingly.” According to the
most recent list compiled by FWS, only 47 of the 375 vertebrates within the United States listed
under the ESA are DPSs.35
Agency Use of DPSs
In six cases, the listing classification of DPSs appears to be used solely to remove animals from
protected status. The DPS designation and the delisting occurred on the same day in the same
30 61 Federal Register at 4725.
31 61 Federal Register at 4724.
32 ESA § 4(b); 16 U.S.C. § 1533(b).
33 61 Federal Register at 4725.
34 61 Federal Register at 4725.
35 The list, dated December 16, 2010, is available from the authors. This list includes the Sonoran Population of the
Bald Eagle, even though its DPS status was ended by a court on September 30, 2010. Center for Biological Diversity v.
Salazar, 2010 WL 3924069 (D. Ariz. September 30, 2010). See also 75 Federal Register 8610 (February 25, 2010)
(publishing FWS determination that a DPS designation was not justified).
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Federal Register notice. Four instances are for gray wolf DPSs. The only designation and
delisting that remained in place (the Columbian white-tailed deer) was the one not challenged in
court. The six DPS designations are:
• Columbian white-tailed deer, Douglas Co. DPS—July 24, 2003;
• Gray wolf, Western Great Lakes DPS—February 8, 2007;36
• Grizzly bear, Yellowstone DPS—March 29, 2007;37
• Gray wolf, Northern Rocky Mountain DPS—February 28, 2008;38
• Gray wolf, Western Great Lakes DPS—April 2, 2009;39
• Gray wolf, Northern Rocky Mountain DPS—April 2, 2009;40
Some have criticized using DPSs to remove ESA protections from certain segments of a listed
species rather than using it to protect species. The district court reviewing a challenge to the 2007
Western Great Lakes DPS designation and delisting suggested that this practice was contrary to
the ESA.41 The court said the ESA did not unambiguously allow a species to be designated as a
DPS at the same time it was delisted, noting that a goal of the Act was to protect species. The
court vacated the designation and the delisting, and remanded the matter to FWS.
In other examples, the species has become downlisted (having its status dropped from endangered
to threatened) the same day as being designated a DPS:
• Gray wolf, Western DPS—downlisted April 1, 2003;
• Gray wolf, Eastern DPS—downlisted April 1, 2003.
In other examples, a gray wolf population has been downlisted (having its status dropped from
endangered to threatened) the same day as it was designated a DPS:
• Gray wolf, Western DPS—downlisted April 1, 2003;
• Gray wolf, Eastern DPS—downlisted April 1, 2003.
However, for many more species, the designation of a DPS increased its protection status, by
protecting a group, even though the species as a whole was not covered by the Act. Examples of
DPS designations resulting in more protection follow:
36 See Humane Society of the United States v. Kempthorne, 579 F. Supp. 2d 7 (D.D.C. 2008) (vacating final rule that
designated and delisted the Great Lakes DPS).
37 Three lawsuits challenged this final rule: two in the District Court of Idaho and one in the District Court of Montana.
The Montana court vacated the DPS designation. Greater Yellowstone Coalition v. Servheen, 672 F. Supp. 2d 1105 (D.
Mont. 2009). The decision is being appealed by FWS. One Idaho case was stayed pending that appeal: Aland v.
Kempthorne, No. CV08-24-S-EJL, 2010 WL 3735490 (D. Idaho September 16, 2010). See also Western Watersheds
Project v. Servheen, No. 07-CV-243-EJL (D. Idaho).
38 The Northern Rockies DPS was later vacated by FWS. See Defenders of Wildlife v. Hall, 08-cv-56-M-DWM (D.
Mont. filed September 22, 2008).
39 74 Federal Register 15069 (April 2, 2009). FWS proposed designating the same DPS and delisting it on May 5,
2011. 76 Federal Register 26086.
40 74 Federal Register 15123 (April 2, 2009). This rule was reissued pursuant to P.L. 112-10. 76 Federal Register
25590 (May 5, 2011).
41 Humane Society of the United States v. Kempthorne, 579 F. Supp. 2d 7 (D.D.C. 2008).
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• California bighorn sheep, Sierra Nevada DPS—listed as endangered January 3,
2000;
• Canada lynx, contiguous U.S. DPS—listed as threatened March 24, 2000;
• Atlantic salmon, Gulf of Maine DPS—listed as endangered November 17, 2000;
• Dusky gopher frog, Mississippi DPS—listed as endangered December 4, 2001;
• Pygmy rabbit, Columbia Basin DPS—listed as endangered March 5, 2003;
• California tiger salamander, Sonoma County DPS—listed as endangered March
19, 2003;
• Northern sea otter, Southwest Alaska DPS—listed as threatened August 9, 2005.
A DPS is treated like a species under the Act; therefore, special rules may also be created for
threatened DPSs.
Gray Wolf Listing
The history of gray wolf protection is interconnected with the history of the ESA. Wolf protection
began at the nascency of the ESA, when it was one of the first mammals covered under the
precursor to the ESA, the Endangered Species Protection Act of 1966.42
At the start, the ESA protected four subspecies of gray wolf: the Mexican wolf, the northern
Rocky Mountain wolf, the eastern timber wolf, and the Texas gray wolf.43 In 1978, the gray wolf
was relisted at the species level as endangered throughout the lower 48 states, except for
Minnesota, where it was listed as threatened.44 As a result of regulatory listings and court
nullifications described below, wolves in the United States have been listed in all of the available
categories for a vertebrate species: (1) never listed (Alaska); (2) delisted (in certain DPSs); (3)
experimental populations (Southwest; Yellowstone and Central Idaho); (4) threatened
(Minnesota); and (5) endangered (every wolf in the lower 48 states that was not in a DPS,
experimental population, or in Minnesota).
Gray Wolf Recovery Plans
Consistent with the ESA requirement of developing recovery plans for listed species, FWS
developed recovery plans for the gray wolf based on its early listing at the subspecies level—the
eastern timber wolf, the Mexican wolf, and the northern Rocky Mountain wolf. The eastern
timber wolf recovery plan was issued in 1978, and revised in 1992.45 The recovery goals were
two-fold: the population in Minnesota must be stable or growing; and a second population of at
42 P.L. 89-669, 80 Stat. 926 (October 15, 1966). The timber wolf and the red wolf were listed under this precursor to the
ESA as being endanger of extinction. 32 Federal Register 4001 (March 11, 1967).
43 See 43 Federal Register 9607 (March 9, 1978).
44 Id.
45 A copy of the 1992 Eastern Timber Wolf Recovery Plan is available at http://ecos.fws.gov/docs/recovery_plans/
1992/920131.pdf.
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least 100 wolves must be sustained for at least five years. If that population was isolated from the
Minnesota population, a population of at least 200 wolves was required.
In 1982, FWS completed the recovery plan for the Mexican wolf.46 The recovery goal was a
viable and self-sustaining population of at least 100 wolves in a 5,000 square mile area within the
Mexican wolf’s historic range.
FWS prepared a recovery plan for the gray wolf in the Northern Rocky Mountains in 1987.47
However, the 1987 recovery goal was later deemed insufficient. It was modified through
scientific inquiry and peer review in 1994 and reaffirmed in 2002.48 The Northern Rocky
Mountain recovery goal is a connected three-state wolf population that never goes below 30
breeding pairs and 300 wolves. Connectivity is a key part of population recovery, as it ensures
adequate genetic exchange for the long-term viability of the species. When wolves are delisted
and state management fully replaces federal management, FWS has determined that the recovery
goal is being maintained when each state (Montana, Idaho, and Wyoming) maintains at least 15
breeding pairs and 150 wolves.49
Experimental Populations of Gray Wolves
Despite near-eradication of the wolf in the lower 48 states, some suitable habitat in the wolf’s
historic range survived, though in a highly modified form. At the end of the 20th century, FWS
planned to reintroduce the wolf to parts of its historic range, using the Ex Pop provisions of the
ESA.
Yellowstone and Central Idaho Ex Pops
No reintroduction was more controversial than that in the greater Yellowstone ecosystem, where
all other large vertebrates were still present, and where many scientists agreed that elk
populations—a favorite wolf prey—had reached harmful levels. In 1995 and 1996 FWS released
66 gray wolves from Canada in Yellowstone and central Idaho. (See Figure 1 and Figure 2.)
46 A copy of the 1982 Mexican Wolf Recovery Plan is available at http://www.fws.gov/southwest/es/mexicanwolf/pdf/
Mexican_Wolf_RP_1982.pdf.
47 A copy of the 1987 Northern Rocky Mountain Wolf Recovery Plan is available at http://www.fws.gov/
montanafieldoffice/Endangered_Species/Recovery_and_Mgmt_Plans/
Northern_Rocky_Mountain_Gray_Wolf_Recovery_Plan.pdf. See discussion of the recovery plan in 73 Federal
Register 15123, 15130-15139 (April 2, 2009). n.b. The Northern Rocky Mountain recovery plan is not based on the
distinct population segment of the same name, which had not been designated at that time.
48 See 68 Federal Register 15804, 15810 (April 1, 2003).
49 See FWS Memorandum, Service review of the 2009 wolf population in the NRM DPS (April 26, 2010), p. 2,
available at http://www.fws.gov/mountain-prairie/species/mammals/wolf/post-delisting-wolf-monitoring/
doc20100428072425.pdf.
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Figure 1. Reintroduction Zone of the
Figure 2. Reintroduction Zone of the
Central Idaho Experimental Population
Yellowstone Experimental Population
Source: 59 Federal Register 60281 (November 22,
Source: 59 Federal Register 60281 (November 22,
1994), as modified by CRS.
1994), as modified by CRS.
Note: This same area was designated for the
Note: This same area was designated for the
population in 2010. 75 Federal Register 65578
population in 2010. 75 Federal Register 65579
(October 26, 2010).
(October 26, 2010).
When wolves were returned, the science community was greatly interested in the potential effects
from a first-ever return of a major predator to a nearly intact ecosystem. The interest was intense
partly because the Yellowstone area was already well studied, with long-term data on many
species, including both competitors (e.g., coyotes and, to some extent, grizzlies) and potential
prey (e.g., elk, moose, and bison). As scientists had expected, wolves had a profound effect on
elk, but there is also evidence of effects that were less predictable—on aspens, cottonwoods,
beavers, beetles, mice, red foxes, ravens, and voles, among others.50 However, the reintroduction
of wolves to Yellowstone was, and still is, fraught with controversy.
Yellowstone and Central Idaho Ex Pop Litigation
While the Northern Rockies gray wolf recovery plan acknowledged that recovery of the species
could require reintroducing it into the area around Yellowstone National Park, the decision to do
so was controversial. Suit was filed to compel FWS to reintroduce wolves to Yellowstone.
However, in 1992, the court ruled that it could not compel FWS to act when Congress had
blocked funding for the reintroduction.51
One legal challenge after the reintroduction was made by a man charged with killing a wolf from
the Yellowstone Ex Pop. He argued that he had killed a Canada wolf, which was not a protected
50 For an account of some of the changes, and a sense of the excitement in the scientific community, see Jim Robbins,
“Lessons from the Wolf,” Scientific American (June 2004).
51 Defenders of Wildlife v. Lujan, 792 F. Supp. 834 (D.D.C. 1992) (referring to P.L. 102-154, 105 Stat. 993-94 (1991)).
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species. This argument failed. The Ninth Circuit upheld the regulations for the experimental
population, holding that once the wolves from Canada were introduced into the park, they became
protected under the ESA.52
Another lawsuit argued that because the Yellowstone Ex Pop may interact and breed with the few
lone wolves in the area,53 the Ex Pop designation violated the ESA Section 10(j) requirement that
experimental populations be “wholly separate geographically from nonexperimental populations
of the same species.”54 The district court ruled that the Yellowstone population would have to be
removed, but was overruled by the Tenth Circuit Court of Appeals.55 The appellate court rejected
the argument that the legislative history of Ex Pops meant that the experimental population must
be separate from every naturally occurring individual animal. The court deferred to the DOI
management plan for the reintroduction, finding that it did not conflict with the statute.
Another claim disputed FWS management of the wolves. A rancher argued the agency failed to
control wolves that were preying on livestock. After FWS killed three wolves, including the lead
male wolf of the offending pack, no more depredations were found. The court dismissed the
claims on procedural grounds.56
The District Court of Montana is considering whether Ex Pops in Yellowstone and central Idaho
no longer fit the statutory definition of an Ex Pop because they are no longer geographically
isolated. The court has suggested that their Ex Pop status would end without further regulatory
action.57 If this is upheld, the wolves in that Ex Pop (which consists only of Wyoming wolves as
of May 5, 2011) would become part of the lower 48 states’ general population and be classified as
endangered.
FWS has argued in its brief to the court that an Ex Pop designation can be removed only through
rulemaking or other regulatory action. Other defendant-intervenors have taken the same position.
In its brief, Safari Club International, a defendant-intervenor, suggested that if the court is right, it
would have a chilling effect on the Ex Pop program. Deregulation of Ex Pops should occur only
when the species is no longer endangered, according to Safari Club International, otherwise
reintroduction of Ex Pops ultimately would lead to larger territories occupied by endangered
species, and would be a disincentive for states, tribes, and other parties to accept Ex Pops on their
land. The plaintiffs argued that the ESA’s definition of Ex Pop58 prohibits FWS from managing a
species as experimental once it is no longer wholly separate geographically from other
populations. FWS has also filed a motion to have the action dismissed, in light of the reissuance
of the 2009 rule as required by P.L. 112-10, § 1713. If granted, the questions raised by the District
Court of Montana would remain unanswered.
52 United States v. McKittrick, 142 F.3d 1170 (9th Cir. 1998).
53 The lone wolves may have been remaining wolves that survived extermination, feral wolves, or wolves naturally
dispersing from farther north.
54 ESA § 10(j)(1); 16 U.S.C. § 1539(j)(1).
55 Wyoming Farm Bureau Federation v. Babbitt, 199 F.3d 1224 (10th Cir. 2000).
56 Gordon v. Norton, 322 F.3d 1213 (10th Cir. 2003).
57 Defenders of Wildlife v. Gould, CV-08-14-M-DWM (D. Mont. January 28, 2011) (Order to Show Cause).
58 16 U.S.C. § 1539(j): “the term ‘experimental population’ means any population ... authorized by the Secretary for
release ... but only when, and at such times as, the population is wholly separate geographically from nonexperimental
populations of the same species.”
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Blue Range Ex Pop
Wolves also had been extirpated in the Southwest. FWS recognized a separate subspecies, the
Mexican wolf (Canis lupus baileyi), which was found in very low numbers in Mexico. After a
cooperative and successful captive breeding program of wolves obtained from Mexico,
reintroduction was begun in 1998, in an area centered in the Apache National Forest in Arizona
and the Gila National Forest in New Mexico. In February 2010 FWS announced that the
population of Mexican gray wolves totaled 42, the lowest since 2002.59 It was a drop from the
previous year’s total of 52, according to the agency. In January 2011 the population totaled 50.60
Blue Range Litigation
Reintroduction of the wolf to the Southwest was no less controversial than that in the Northern
Rockies. Ranchers sued, claiming the action violated the National Environmental Policy Act
(NEPA), as well as the ESA. The District Court of New Mexico found for FWS, even though
livestock owners and FWS had different estimates as to the impact of the wolves on domesticated
stock.61
Even after the Southwest wolf reintroduction, the area remains a center of intense public
controversy. Environmentalists sued FWS for not acting to modify the reintroduction
regulations.62 The action was dismissed as moot. A different suit brought by ranchers argued that
the reintroduction violated the ESA and NEPA in part because the wolves were hybrids. The suit
was dismissed.63 In 2010 the Center for Biological Diversity filed suit to force the listing of the
Mexican gray wolf as either an endangered species or a DPS.64 If successful, the suit would end
the Ex Pop status of the Mexican gray wolf and the exceptions that allow takes of those wolves.
Gray Wolf DPSs
The gray wolf was originally listed at the species level as threatened in Minnesota, and
endangered in the remainder of the lower 48 states. Since the issuance of the DPS Policy, FWS
has pursued dividing the gray wolf into DPSs.65 DPSs supplant Ex Pops, but when a DPS has
been nullified, FWS returns the population to its Ex Pop status. All DPS designations were
challenged in federal court, and each court rejected FWS’s action, leading to each rule being
withdrawn.
59 FWS Southwest Region Press Release: “2009 Mexican Wolf Population Survey Complete” (February 5, 2010),
available at http://www.fws.gov/southwest/docs/WolffinalPopCount2009NewsReleaseFeb52010.pdf.
60 FWS, Blue Range Wolf Reintroduction Area Monthly Project Updates, available at http://www.fws.gov/southwest/
es/mexicanwolf/BRWRP_notes.cfm.
61 New Mexico Cattle Growers v. U.S. Fish and Wildlife Service, 1999 WL 34797509 (D.N.M. 1999).
62 Center for Biological Diversity v. Kempthorne, 498 F. Supp. 2d 293 (D.D.C. 2007).
63 Coalition of Arizona/New Mexico Counties for Stable Economic Growth v. U.S. Fish and Wildlife Service, 1:03-cv-
00508 (D.N.M. January 31, 2005). That suit had also sought release of the location of a den of wolf pups.
64 Center for Biological Diversity v. Salazar (D.D.C. filed January 2010).
65 Efforts to name the wolves of the Alexander Archipelago in Alaska as threatened or endangered have not succeeded.
See Biodiversity Legal Foundation v. Babbitt, 943 F. Supp. 23 (D.D.C. 1996) (remanding the decision not to list the
Alexander Archipelago gray wolf to DOI, as its decision was not based solely on the best scientific and commercial
data); 62 Federal Register 46709 (September 4, 1997) (upon remand, no finding that the wolf was threatened).
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2003 Western, Eastern, and Southwestern DPSs
In 2003, FWS divided gray wolves into three DPSs, Western, Eastern and Southwestern, and
downlisted the Eastern and Western DPSs from endangered to threatened.66 At the same time,
FWS removed gray wolves from ESA protection in all or parts of 16 southern and eastern states
where they did not occur historically. Wolves in the Southwest remained listed as endangered.
Western, Eastern, and Southwestern DPS Litigation
The 2003 rule was challenged in two federal district courts. The plaintiffs before the District
Court of Oregon disputed how the DPS ranges were designated. They argued that FWS
considered only where the wolves were currently located when determining their viability. This
allowed FWS to count wolves only in the areas they occupied. Despite finding that areas outside
of the wolves’ current range were suitable habitat, although no wolves were present, FWS did not
include those areas in defining the DPS ranges. The plaintiffs argued that this method was
contrary to the ESA and prior case law, because the Act requires that a species is endangered if it
is at risk of extinction in “all or a significant portion of its range.” In 2005, the court agreed that
FWS had violated the ESA by equating the wolves’ current range with a significant portion of its
range.67 The court vacated the rule, effectively eliminating the three DPSs and reinstating their
protected status.
The other suit was before the District Court for Vermont, which issued a decision eight months
after the Oregon court. The plaintiffs in Vermont challenged the rule’s final designation of one
Eastern DPS, when two DPSs had been proposed for that area: a Northeast DPS and a Western
Great Lakes DPS. In 2005, the court found procedural flaws and also that FWS failed to consider
significant portion of its range in a way consistent with the ESA.68 The court criticized FWS’s
method before vacating the rule: “The FWS simply cannot downlist or delist an area that it
previously determined warrants an endangered listing because it ‘lumps together’ a core
population with a low to non-existent population outside of the core area.”69
2007 Western Great Lakes DPS and 2008 Northern Rocky Mountain
DPS
After the 2003 DPS rulemaking was nullified in 2005, FWS proposed two other gray wolf DPSs:
Northern Rocky Mountain and Western Great Lakes.70 In 2007, the Western Great Lakes gray
66 68 Federal Register 15803 (April 1, 2003). This rule was vacated by court order. See Defenders of Wildlife v. U.S.
Dept. of the Interior, 354 F. Supp. 2d 1156 (D. Or. 2005).
67 Defenders of Wildlife v. U.S. Dept. of the Interior, 354 F. Supp. 2d 1156 (D. Or. 2005).
68 National Wildlife Federation v. Norton, 386 F. Supp. 2d 553 (D. Vt. 2005). FWS changed its interpretation of a
significant portion of its range, and then withdrew that interpretation without providing another. See DOI Solicitor’s
Opinion, M-37013 (March 16, 2007), available at http://www.doi.gov/solicitor/M37013.pdf; Memorandum of the
Solicitor, Withdrawal of M-37013—The Meaning of “In Danger of Extinction Throughout All or a Significant Portion
of its Range,” M-37024 (May 4, 2011), available online at http://www.doi.gov/solicitor/opinions/M-37024.pdf.
69 National Wildlife Federation v. Norton, 386 F. Supp. 2d at 556.
70 The Northern Rocky Mountain DPS includes Washington, Oregon, Utah, Montana, Idaho, and Wyoming; the
Western Great Lakes DPS includes North Dakota, South Dakota, Minnesota, Wisconsin, and Michigan.
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wolf population was declared a DPS and delisted in the same notice.71 That final rule was vacated
by the District Court for the District of Columbia in 2008.72 On the same date as the Western
Great Lakes rule was issued, FWS proposed designating a Northern Rocky Mountain gray wolf
DPS and delisting its population (see Figure 3), except for the Wyoming population because
Wyoming’s state laws were found to provide insufficient protection for the wolf.73 In the 2008
final rule, FWS designated and delisted Northern Rocky Mountain DPS, including Wyoming.74
2007 Western Great Lakes DPS Litigation
In September 2008, the District Court for the District of Columbia vacated the final rule that
designated and delisted the Western Great Lakes DPS.75 Unlike the holding in the Northern
Rockies DPS case (below), this decision focused on the procedure, not the science, behind the
rule. The plaintiffs claimed that FWS had violated the Act by issuing the designation and delisting
simultaneously, while FWS argued that the ESA “unambiguously” supported its process. In light
of the Act’s purpose in conserving species, the court found the ESA was not unambiguous. The
court remanded the action to the agency to find a “reasonable explanation” for its interpretation
that the ESA supports a designate and delist rule.76 Instead, in December 2008, FWS reinstated
the wolves in the area as either threatened (in Minnesota) or endangered.77
2008 Northern Rocky Mountain DPS Litigation
In July 2008, the District Court for the District of Montana issued a preliminary injunction halting
the effectiveness of the FWS delisting of the Northern Rockies DPS.78 The delisting had found
that Wyoming, Idaho, and Montana had adequate wildlife management programs to support
populations above recovery levels.79 However, the court rejected FWS’s contention that there was
genetic exchange between the Yellowstone experimental population and other packs in the
Northern Rockies. (Figure 3 shows the distribution of wolf packs in the two areas in 2008.)
Without sufficient genetic exchange, the isolated wolf populations would not be genetically
diverse enough to avoid inbreeding, and therefore could not be termed recovered. The court also
found that the states’ management plans did not seem adequate to support wolf recovery levels.
The order reinstated the wolf as endangered until final disposition. In September 2008 FWS
voluntarily moved to withdraw the rule.80 Wolves in that area returned to being nonessential
71 72 Federal Register 6052 (February 8, 2007).
72 Humane Society of the United States v. Kempthorne, 579 F. Supp. 2d 7 (D.D.C. 2008).
73 72 Federal Register 6106 (February 8, 2007). In 2006 FWS had found the petition to designate the Northern Rockies
DPS and delist that segment was unwarranted, due to Wyoming’s inadequate management plan. 71 Federal Register
43410 (August 1, 2006).
74 73 Federal Register 10514 (February 27, 2008).
75 Humane Society of the United States v. Kempthorne, 579 F. Supp. 2d 7 (D.D.C. 2008). As a result of this ruling,
wolves in that area were returned to the endangered species list, except for Minnesota wolves, which are listed as
threatened.
76 Humane Society of the United States v. Kempthorne, 579 F. Supp. 2d 7, 20 (D.D.C. 2008).
77 73 Federal Register 75356 (December 11, 2008).
78 Defenders of Wildlife v. Hall, 08-cv-56-M-DWM, 2008 U.S. Dist. LEXIS 55071 (D. Mont. July 18, 2008).
79 73 Federal Register 10514 (February 27, 2008).
80 Defenders of Wildlife v. Hall, 08-cv-56-M-DWM (D. Mont. filed September 22, 2008).
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experimental populations with special regulations allowing takes.81 (See below at “Section 4(d)
Rules for Gray Wolves.”)
Figure 3. Northern Rocky Mountain Gray Wolf DPS Area in 2008
Showing Individual Wolf Pack Territories
Source: 73 Federal Register 10517 (February 27, 2008).
Note: This distribution of territories can be expected to change over time.
2009 Western Great Lakes and Northern Rocky Mountain DPSs
In April 2009, FWS designated wolves in the Western Great Lakes and the Northern Rockies as
DPSs and delisted them.82 Once again, an exception was made for the wolves of Wyoming. The
81 73 Federal Register 75356 (December 11, 2008).
82 74 Federal Register 15069 (April 2, 2009) (Western Great Lakes); 74 Federal Register 15123 (April 2, 2009)
(Northern Rockies). In January 2009 FWS had announced it was delisting the DPSs. See FWS Press Release, “Service
Removes Western Great Lakes, Portion of Northern Rocky Mountain Gray Wolf Populations from Endangered Species
List” (January 14, 2009), available at http://www.fws.gov/news/NewsReleases. But the January rulemaking was halted
by the new administration. See Rahm Emanuel, Memorandum for the Heads of Executive Departments and Agencies
(January 20, 2009), available at http://ombwatch.org/regs/midnightregfreezememo.pdf.
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Wyoming population was not delisted because FWS found that Wyoming’s regulatory framework
would not maintain the targeted population goals to ensure genetic health for a viable population
in the foreseeable future.83
2009 Western Great Lakes DPS Litigation
Suit was filed regarding the Western Great Lakes delisting, and was settled in September 2009.84
FWS withdrew the 2009 rule and reinstated the gray wolf as endangered throughout most of the
area and as threatened in Minnesota.85
2009 Northern Rocky Mountain DPS Litigation
In August 2010, the District Court of Montana declared the April 2009 Northern Rocky Mountain
rule invalid.86 The court held that segregating the Wyoming wolves from the rest of the Northern
Rockies DPS violated the ESA by creating a regulatory taxonomic category not allowed by the
Act. The ESA does not allow listing (or delisting) part of a DPS, such as wolves in Wyoming,
according to the court.87 The wolves were returned to their status as an experimental population
and again treated as threatened.88
The State of Wyoming sued FWS for finding its regulatory plan did not meet recovery goals for
the wolf. In November 2010, the District Court for Wyoming held that FWS had acted arbitrarily
and capriciously by requiring the Wyoming plan to designate all of the state as trophy-game area,
meaning a permit would be required to kill a wolf.89 Instead, the state plan designated
approximately 90% of the state as predator areas (not including National Parks), meaning no
permit was required to kill a wolf. The Wyoming plan also required the state to maintain no fewer
than seven packs outside of National Parks. The court remanded to FWS to see if the Wyoming
plan met the federal recovery goals of 15 packs statewide, as well as genetic diversity.
Another lawsuit filed in the District Court of Montana on behalf of Washington cattle ranchers
claimed FWS has failed to conduct five-year reviews of the gray wolf as required under Section
1533(c)(2).90 Because five-year reviews are required to see if delisting or downlisting is
appropriate, it is possible that a court could find that FWS has conducted such a review pursuant
to the two rulemakings to delist the wolf, a process that requires “conducting a review of the
status of the species.”91 If successful, the suit would force FWS to perform a five-year review,
perhaps taking resources away from its efforts to delist the wolf. On May 5, 2011, FWS
83 74 Federal Register at 15125.
84 Humane Society of the United States v. Salazar, 1:09–CV–1092–PLF (D.D.C.).
85 74 Federal Register 47483 (September 16, 2009).
86 Defenders of Wildlife v. Salazar, 729 F. Supp. 2d 1207 (D. Mont. 2010).
87 Defenders of Wildlife v. Salazar, 729 F. Supp. 2d 1207 (D. Mont. 2010).
88 75 Federal Register 65574 (October 26, 2010).
89 Wyoming v. U.S. Department of the Interior, No. 09-CV-118J, 2010 U.S. Dist. LEXIS 122829 (D. Wyo. November
18, 2010).
90 Washington Cattlemen’s Association v. Salazar, 11-cv-03019 (E.D. Wash. complaint filed February 16, 2011).
91 16 U.S.C. § 1533(b)(1)(A).
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announced it would conduct a status review of the gray wolf, which could render the lawsuit
moot.92
Conditional Settlement Reached and Then Halted
In March 2011 FWS announced it had reached a settlement agreement with many of the plaintiffs
that had challenged the 2009 Northern Rocky Mountain DPS rule.93 However, the District Court
of Montana rejected a motion needed to implement the agreement,94 and legislation by the 112th
Congress mooted its necessity. (See “Legislation Directing Delisting of the Northern Rocky
Mountain DPS” below.) However, even if enacted, the agreement would not have marked the end
of litigation in the area: four plaintiffs refused to participate in the agreement, and, of the
defendant-intervenors, only Montana indicated it supported the action.95
The agreement depended on the District Court of Montana partially revoking the stay put in place
while its August 2010 decision was appealed,96 thus allowing Idaho and Montana to resume
management of wolves in their state pursuant to plans approved by the FWS. The court held that
it lacked authority to take that step because doing so would allow a protected species to be killed
in violation of the ESA. If the settlement had been implemented, both Montana and Idaho could
allow killing wolves, even though under the ESA, those wolves were protected species. In
addition to lacking legal authority, the court also found that revoking the stay would violate
notions of equity. The non-settling plaintiffs and the defendant-intervenors who had not signed on
to the agreement would not be able to continue their legal challenges.
The court noted weaknesses in the agreement. In addition to binding non-settling plaintiffs to a
conclusion they opposed, the court found that although FWS had agreed to withdraw its
Solicitor’s Opinion regarding the meaning of significant portion of its range,97 it had not agreed
to issue a new opinion.98 Also, the additional monitoring FWS would perform under the
agreement would not take place for three years, leaving the status of the wolf unknown during
that time.
92 76 Federal Register 26086 (May 5, 2011).
93 Defenders of Wildlife v. Salazar, CV-09-77-M-DWM (D. Mont. March 18, 2011) (Motion to Partially Stay August
5, 2010 Judgment). The settling plaintiffs are: Defenders of Wildlife, Natural Resources Defense Council, Sierra Club,
Center for Biological Diversity, Hells Canyon Preservation Council, Greater Yellowstone Coalition, Jackson Hole
Conservation Alliance, Oregon Wild, Cascadia Wildlands Project, and Wildlands Network. Plaintiffs that did not
participate in the settlement include Humane Society of the United States, Friends of the Clearwater, Alliance for the
Wild Rockies, and Western Watersheds Project.
94 Defenders of Wildlife v. Salazar, 09-cv-77-DWM (D. Mont. April 9, 2011).
95 Safari Club International took no position as of the date the motion was filed. Other groups did not respond by that
date: Sportsmen for Fish and Wildlife, the National Rifle Association, the Montana Farm Bureau Federation, the Idaho
Farm Bureau Federation, the Mountain States Legal Foundation, and the Rocky Mountain Elk Foundation.
96 Defenders of Wildlife v. Salazar, 729 F. Supp. 2d 1207 (D. Mont. 2010) (see above).
97 Memorandum of the Solicitor to FWS Director, The Meaning of “In Danger of Extinction Throughout All or a
Significant Portion of its Range,” M-37013 (March 16, 2007), available at http://www.doi.gov/solicitor/opinions/M-
37013.pdf.
98 This turns out to be exactly what happened. See Memorandum of the Solicitor, Withdrawal of M-37013—The
Meaning of “In Danger of Extinction Throughout All or a Significant Portion of its Range,” M-37024 (May 4, 2011),
available online at http://www.doi.gov/solicitor/opinions/M-37024.pdf.
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Comparative Wolf Density Before the Reissuance of the April 2009
Rule
The Northern Rocky Mountain DPS and the Western Great Lakes DPS have charted parallel
regulatory courses, and both populations have grown over the past two decades. However, data
show that in terms of wolves per square mile, wolf density is much greater in the Western Great
Lakes than in the Northern Rocky Mountains. Despite this, Congress has introduced more bills
targeting delisting Northern Rocky Mountain wolves than those in the Great Lakes area,
including the bill enacted as P.L. 112-10.
Figure 4. Wolf Density as of 2009
Source: Congressional Research Service, based on 2009 data provided by FWS and Montana Fish, Wildlife and
Parks.
Note: The DPSs shown in this map were nullified, although the Northern Rocky Mountain DPS was reinstated
as directed by P.L. 112-10, § 1713. Maps of wolf pack territories for the Western Great Lakes and the Blue
Range are not available. BRWRA is an abbreviation for Blue Range Wolf Recovery Area.
CRS calculated the areas shown as “Core Wolf Populations” in Figure 4, based upon data
provided by FWS and Montana Fish, Wildlife and Parks. These data showed that the Core Wolf
Population area in the Western Great Lakes is approximately 78,775 sq. miles and the Northern
Rocky Mountains Core Wolf Population area is about 134,697 sq. miles. Based on 2010 wolf
populations, the Western Great Lakes has 4,169 wolves in 78,775 sq. miles, or approximately 53
wolves per 1,000 sq. miles. The Northern Rocky Mountains DPS has 1,651 wolves in about
134,697 sq. miles, making for a less dense population of 12 wolves per 1,000 sq. miles.
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2011 Regulatory and Legislative Activity
Legislation Directing Delisting of Northern Rocky Mountain DPS:
P.L. 112-10, § 1713.
Following successive court orders invalidating FWS’s delisting rules, and in light of increasing
populations of wolves in some parts of the country, the 111th Congress began to consider
legislative options to exclude the wolf from the protections of the ESA. The 112th Congress
passed the first law to delist a species. The Full-Year Appropriations Act of 2011, P.L. 112-10,
§ 1713, directs FWS to delist the gray wolf in Montana, Idaho, eastern Washington, eastern
Oregon, and north-central Utah, but leaves the wolves in the remaining lower 48 states federally
protected as either threatened or endangered. Enactment of P.L. 112-10, § 1713 was significant
because legislation to delist species rarely had been proposed and never had been successful.99
Some have argued that P.L. 112-10 is a tipping point in species protection—that politics and not
science will dictate species protection in the future. However, Section 1713 is not a blanket
delisting, but a direction to re-release the April 2009 rule in which FWS determined that the best
available science supported delisting those wolves. As referenced above, however, a federal court
found FWS had violated the ESA in making this determination.100 P.L. 112-10 bars judicial
review of the rule, but still allows regulatory actions, such as delisting in Wyoming, or relisting of
the DPS, should the wolf’s status change. Section 1713 states that it does not alter the November
2010 Wyoming District Court ruling that remanded Wyoming’s management plan to FWS. FWS
reissued the 2009 rule on May 5, 2011.101
Proposed Gray Wolf Legislation
Other bills still pending in the 112th Congress would restrict federal protection of the gray wolf.
Those addressing the wolves of the West may not be advanced in light of P.L. 112-10. For
example, Congress apparently chose P.L. 112-10, § 1713 over the nearly identical version in S.
321 (Baucus), which would have given the 2009 rule the force of law rather than regulation.
Additionally, H.R. 510 (Rehberg), which allows state regulation of wolves in Idaho and Montana,
appears mooted by that law.
99 All examples were from the 100th Congress and were proposed amendments to the Endangered Species Act
Amendments of 1987. They were not passed. See 133 Cong. Rec. H11248 (proposed amendment to prevent the
Concho water snake from being considered a listed species); 133 Cong. Rec. H11248 (proposed amendment to prevent
the gray wolf from being considered a listed species); and 133 Cong. Rec. H11617 (proposed amendment to prevent the
leopard darter minnow from being considered a listed species). Also, for details of the 48 species that had been delisted
before passage of § 1713, see http://ecos.fws.gov/tess_public/pub/delistingReport.jsp.
100 Defenders of Wildlife v. Salazar, 729 F. Supp. 2d 1207 (D. Mont. 2010).
101 76 Federal Register 25590 (May 5, 2011).
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Other bills do not appear moot. For example, H.R. 838 (Kline) would eliminate federal protection
of wolves in the Western Great Lakes area, proposing: “Any wolf in Minnesota, Wisconsin, or
Michigan shall not be treated under any status of the Endangered Species Act of 1973 (16 U.S.C.
§§ 1531 et seq.), including as an endangered species, a threatened species, an essential
experimental population, or a nonessential experimental population.”102 H.R. 509 (Rehberg) and
S. 249 (Hatch) would amend the ESA so the Act would not apply to the gray wolf. Those two
bills would affect all gray wolves, including the populations in the Southwest as well as the
Western Great Lakes and Northern Rocky Mountain areas.
After the delisting directed by P.L. 112-10 went into effect, Representative Candice S. Miller
introduced H.R. 1819 which would give states management authority over wolves provided that
specified population levels were maintained. H.R. 1819 addresses all three gray wolf103
population centers, the Northern Rockies, the Western Great Lakes, and the Southwest. For each
population, if the numbers of wolves dip below a statutorily protected amount, the Secretary of
the Interior would be authorized to treat wolves as protected for at least two years after
reestablishing the targeted number of wolves. Under H.R. 1819, population goals would not be
based on breeding pairs but on individuals. This criterion is not as clearly related to adequate
genetic diversity and reproductive capacity, and might arguably be more difficult to measure than
the number of breeding pairs.104
Proposed Rulemaking: Redefining Populations, Species, and
Range
On May 5, 2011, in addition to reissuing the Northern Rocky Mountain DPS rule, FWS proposed
changes to gray wolf protection. FWS proposed to do the following: designate the Western Great
Lakes as a DPS and delist that DPS; revise the gray wolves’ historic range by eliminating parts or
all of 29 eastern states; initiate a five-year review for the gray wolf; initiate a status review of the
gray wolf in the Pacific Northwest; initiate a status review of the Mexican wolf in the Southwest
and Mexico; and recognize a new species of wolf, the eastern wolf (Canis lycaon).105 Some of the
proposed actions could lead to further differentiated protection of wolves depending on location.
Wolf protection under the proposed rule would be as shown in Figure 5.
102 This language appears to mean that Minnesota, Wisconsin, and Michigan wolves shall not be treated as protected
under or covered by the ESA, but those italicized words are not in the bill. It is not clear how H.R. 838 would affect
existing federal protection because of this wording.
103 The bill defines gray wolf to include Canus [sic] lycaon, and Canus [sic] lupus baileyi (the Mexican wolf).
104 Lone wolves are often secretive and hide to avoid attack by resident packs.
105 76 Federal Register 26086 (May 5, 2011).
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Figure 5. Gray Wolf Protection Proposed by 76 Federal Register 26086
May 5, 2011
Source: Congressional Research Service, compiled from FWS data.
Proposed New Species: The Eastern Wolf
The Eastern DPS designation of the gray wolf was rejected by courts in 2005 and has not been
proposed by FWS since then. However, FWS proposed recognizing a new species of wolf, the
eastern wolf (Canis lycaon), using newer methodology in distinguishing among species, which
relies in part on DNA.106 The proposed eastern wolves’ historic range would include portions of
eastern Canada, the Western Great Lakes, and the northeastern United States.
From a scientific point of view, designating wolves found in the eastern United States as a
separate species is not assured. For example, the encyclopedic Mammal Species of the World
discusses the validity of Canis lycaon as a distinct species and concludes that evidence for
separation is equivocal.107 However, it does not currently consider this wolf in the East to be a
distinct species. Moreover, the North American consortium of national professionals who manage
the Integrated Taxonomic Information System (ITIS, the source considered authoritative on
taxonomy and taxonomic validity in the United States and its territories, Mexico, and Canada)
currently considers this wolf as a subspecies (Canis lupus lycaon).108 The validity debate
106 76 Federal Register 26086 at 26088-89 (May 5, 2011).
107 Don E. Wilson & DeeAnn M. Reeder (editors), Mammal Species of the World. A Taxonomic and Geographic
Reference (3rd ed.), Johns Hopkins University Press: 2005.
108 The ITIS data base is on-line at http://www.itis.gov/.
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considers evidence related to mitochondrial DNA, morphology, evidence of hybridization with
coyotes, the natural variability of widely distributed species, and the extremely low population
densities that make conclusive evidence difficult to obtain.
Designating a new wolf species is likely to be controversial. Based on the results of the status
review, petitions to list the species could be filed. However, lawsuits are unlikely until a listing
determination is made, or a DPS designated. Subspecies designation has been controversial in
other cases, but typically it is FWS resisting the change, not making it. For example, multiple
petitions have been filed to designate two subspecies of the greater sage grouse, with FWS
ultimately rejecting those petitions, finding the science did not support the distinctions.109 Legal
challenges to the science behind the subspecies classifications or DPS designations are not
uncommon and can be successful.110 However, they are fact-specific cases in which the court’s
view of the agency’s scientific basis determines the outcome of the case.
The agency is initiating a review of the eastern wolves’ status, which could result in listing the
eastern wolf under the ESA, either on the FWS’s initiative or by petition. Given its status as a
proposed new species, the eastern wolf is not protected under the Act, although gray wolves in the
eastern half of the United States are listed as threatened (if in Minnesota) or endangered.111 If
made final, the effect of the scientific reclassification would be delisting wolves that currently
enjoy ESA protection.
Listing the eastern wolf as a separate species could affect gray wolf protection, even if the gray
wolf is entirely delisted by then. The eastern wolf could be found to be endangered—no breeding
pairs of eastern wolves are reported outside of the Western Great Lakes area, yet it is expected to
have a broad historic range. Then, despite the proposed rule to delist the Western Great Lakes
DPS, eastern wolf protection could mean the gray wolf in the Western Great Lakes area might be
protected under the ESA provision safeguarding species with similar appearances to listed
species.112 After all, FWS only recently determined a distinction between the gray and eastern
wolf species, and that distinction requires a DNA test.
Other Status Reviews
In addition to the five-year status review for the gray wolf, and the review of the proposed eastern
wolf, FWS proposes two other status reviews in the May 5 notice. FWS plans to consider
populations in the Pacific Northwest and the Southwest. These reviews could find wolves in those
areas should be appropriately designated as DPSs. Gray wolf protections could be altered
109 See 68 Federal Register 6500 (February 7, 2003) (finding insufficient evidence that the western sage grouse is a
subspecies of the greater sage grouse); 69 Federal Register 933 (January 7, 2004) (denying petition to list eastern
grouse as a subspecies because science did not support the finding); 75 Federal Register 13909 (March 23, 2010)
(denying petition to list western grouse as a subspecies, finding no genetic evidence supporting a subspecies).
110 Center for Biological Diversity v. Kempthorne, CV-07-0038-PHX-MHM (D. Az. March 5, 2008) (holding that the
FWS was arbitrary and capricious in finding Sonoran bald eagles were not a DPS); Institute for Wildlife Protection v.
Norton, 174 Fed. Appx. 363, 2006 WL 536088 (9th Cir. 2006) (holding that finding western sage grouse was not a
subspecies was arbitrary and capricious). But see Center for Biological Diversity v. Badgley, 335 F.3d 1097 (9th Cir.
2003) (finding that FWS was not arbitrary and capricious in denying petition that the northern goshawk in the western
United States was a distinct population).
111 As discussed above, FWS has proposed ending those protections.
112 16 U.S.C. § 1533(e).
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population by population. This would be consistent with FWS’s statement that it intends to
replace the 48-state listing with “more targeted regional units.”113
Proposed Alteration of Historic Range
It is unclear what effect the proposed removal of most of 29 states from the historic range114 of
the gray wolf may have on the animal’s protection. However, taken in context with FWS’s
interpretation of significant portion of its range within the May 5 proposed rulemaking,115 which
is discussed below, it could lead to more delisting.
A species is listed under the ESA depending on its presence in its range.116 However, despite
having an enormous range across the continent of North America, the gray wolf has always had
different protection status based on its location—for example, the gray wolf has never been
protected in Alaska. The FWS website for the gray wolf shows how the listing status varies based
on population location.117 In contrast, the listing for the tiger shows it is protected “wherever
found,” and the polar bear is listed throughout its entire range.118 As discussed earlier in this
report, the gray wolf’s history is one of designating and delisting DPSs. Eliminating such a great
area from the wolves’ range could lead to a finding that in its (now much smaller) historic range
wolves have a proportionally larger population—perhaps leading to a finding that wolf
populations have recovered there. Thus, it could lead to a finding that gray wolves need less
protection in the West. Another possibility is that it could lead to a finding that no protection of
gray wolves is necessary in the eastern 29 states as FWS has stated that no such population ever
existed there.
Interpretation of Significant Portion of Its Range
FWS’s interpretation of significant portion of its range, announced May 5, 2011, to support its
proposed delisting of the Western Great Lakes DPS, appears to support these theories. For the
proposed rulemaking, FWS stated that a portion of a species’ range is significant if it meets two
criteria: (1) it is part of the current range of the species; and (2) it is important to the species’
conservation “because it contributes meaningfully to the representation, resiliency, or redundancy
of the species.”119
It could be argued that the focus on a species’ current range artificially limits the scope of the
ESA listing process. Under that theory, a species is important only where it exists today. Courts
rejected a seemingly identical interpretation when it was used in the 2003 designation and revised
113 76 Federal Register at 26142.
114 The term historic range has no definition in regulation or law. However, it is used as that area where a species once
existed, even if it no longer occupies that area.
115 On May 4, 2011, the DOI Solicitor withdrew the opinion interpreting significant portion of its range, but did not
replace it. Memorandum of the Solicitor, Withdrawal of M-37013—The Meaning of “In Danger of Extinction
Throughout All or a Significant Portion of its Range,” M-37024 (May 4, 2011), available online at http://www.doi.gov/
solicitor/opinions/M-37024.pdf.
116 16 U.S.C. § 1532(6): endangered species “means any species which is in danger of extinction throughout all or a
significant portion of its range.”
117 See http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=A00D.
118 See http://ecos.fws.gov/tess_public/pub/listedAnimals.jsp.
119 76 Federal Register at 26140,
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listing of the Western, Eastern, and Southern DPSs, discussed above.120 The interpretation
essentially eliminates consideration of a species’ historic range and restricts the review of a
species’ health to where it is now present. It could skew the listing process, eliminating
consideration of areas where a species once was abundant but now is extirpated.
The second criteria of FWS’s May 5 interpretation—that the area contributes meaningfully to the
species—further limits the area being considered, and so does not appear to avoid this conflict
with court precedent.
Additionally, FWS’s interpretation appears to conflict with other portions of the Act, which
require consideration of a broader area than a species’ current range. Under FWS’s interpretation,
it would be possible to establish critical habitat of a species in an area that FWS says is not part of
its range. ESA defines critical habitat to include areas not just currently occupied by the species
at the time of listing, but also “specific areas outside the geographical area occupied by the
species at the time it is listed ... upon a determination by the Secretary that such areas are
essential for the conservation of the species.”121
The interpretation also may be seen as inconsistent with the statutory requirement that listing be
based in part on the “present or threatened destruction, modification, or curtailment of its habitat
or range.”122 If a species has already been chased out of damaged habitat, evaluation of its
presence in only its current range may seem to restrict consideration of this factor.
120 See Defenders of Wildlife v. U.S. Dept. of the Interior, 354 F. Supp. 2d 1156 (D. Or. 2005); National Wildlife
Federation v. Norton, 386 F. Supp. 2d 553 (D. Vt. 2005).
121 16 U.S.C. § 1532(5)(A) (emphasis added).
122 16 U.S.C. § 1533(a)(1)(A).
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Appendix.
Section 4(d) Rules for Gray Wolves
According to FWS, Section 4(d) rules are intended to reduce conflicts between the provisions of
the Act and needs of people near the areas occupied by the species. Special rules have been in
effect for the threatened gray wolves in Minnesota for many years, and were extended to gray
wolves in other states, when and where the wolf was downlisted. Under the rule for Minnesota,
individual “wolves that have preyed on domestic animals can be ... killed by designated
government agents.”123 FWS asserts that this rule avoids “even larger numbers of wolves being
killed by private citizens who might otherwise take wolf control into their own hands.”124
In 2003 as part of the rulemaking that was vacated, FWS issued special rules for two DPSs:
Eastern and Western. The special rules would have allowed individuals to kill Western DPS
wolves in the act of attacking livestock on private land, and to harass wolves near livestock.
Permits to kill wolves could also be issued to landowners who showed wolves routinely were
present and formed a significant risk to livestock. FWS said that, as in Minnesota, the rule would
“increase human tolerance of wolves in order to enhance the survival and recovery of the wolf
population.”125 Michigan and Wisconsin citizens would be able to kill any wolf within one mile
of killed livestock, and in other Eastern states beside Minnesota, any lethal measures could be
used within four miles of such a site.126 This rule was vacated, as discussed in “2003 Western,
Eastern, and Southwestern DPS Litigation.” When FWS settled the case challenging the 2009
delisting of the Western Great Lakes DPS, the special rule was put back into effect.127
Section 4(d) Rules for Yellowstone and Idaho Experimental
Populations
In 2005 after FWS found that the wolf population had exceeded its minimum recovery goals of
30 breeding pairs for Yellowstone and Central Idaho, it issued a rule to manage wolves where
they had an unacceptable impact on ungulate populations.128 This 2005 Rule modified the
provisions put in effect when the wolves were first introduced, which stated that “wolves could
not be deliberately killed solely to resolve predation conflicts with big game.”129 When the 2009
123 See FWS Western Region, Little Known But Important Features of the Endangered Species Act, online at
http://www.fws.gov/pacific/news/grizzly/esafacts.htm.
124 Id. See 50 C.F.R. § 17.40(d) for the rule.
125 68 Federal Register at 15864.
126 68 Federal Register at 15868.
127 74 Federal Register 47483 (September 16, 2009).
128 70 Federal Register 1285 (January 6, 2005) (hereinafter the “2005 Rule”). Unacceptable impact was defined as
“State or Tribally-determined decline in a wild ungulate population or herd, primarily caused by wolf predation, so that
the population or herd is not meeting established State or Tribal management goals.” Id. at 1307.
129 59 Federal Register 60252, 60255 (November 22, 1994) (Yellowstone); 59 Federal Register at 60272 (Idaho)
(“wolves will not be deliberately killed solely to address ungulate-wolf conflicts”).
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Northern Rocky Mountains DPS rule was reissued, the special rule for the Wyoming Ex Pop was
returned to effect.130
The 2005 Rule allowed states and tribes in the area to kill wolves where it was shown they were
adversely affecting the populations of deer, antelope, elk, big horn sheep, mountain goats, bison,
or moose in the area. Before the states and tribes could act, they were required to submit the plan
for peer review, public comment, and FWS approval. Data at the time, from many sources cited
by FWS, showed that wolf predation was “unlikely to be the primary cause of a reduction of any
ungulate herd or population in Idaho, Wyoming, or Montana.”131 FWS reported that more wolves
were killed (by wildlife agents or by hunting) in each year from 2007 through 2010, than cattle
were killed by wolves.132 The wolf population in the area was estimated at 1,651 for 2010.133
In 2008 FWS changed the special rule.134 FWS determined that the definition of unacceptable
impact had to be altered, as wolves were not the primary cause in ungulate population decreases.
Accordingly, the definition was modified to mean: “Impact to a wild ungulate population or herd
where a State or Tribe has determined that wolves are one of the major causes of the population
or herd not meeting established State or Tribal population or herd management goals.”135 Public
and peer reviews are still required. The plan allows a state to kill wolves, provided the
experimental population does not go below 20 breeding pairs in the state.136 Additionally, wolves
found by wildlife officials to be hybrids may be killed.137
The 2008 Rule also expands the provision for killing wolves when they are in the act of attacking
livestock or dogs. The 2005 Rule allowed an individual to “take” a wolf that was in the act of
attacking stock animals or dogs on private property. The 2008 Rule allows individuals to take
wolves that are in the act of attacking livestock or dogs on public lands as well, except for
National Park Service property.138 When the 2009 delisting of the Northern Rockies DPS was
invalidated by a court, FWS reinstated the special rules regarding the Ex Pops in the area.139
130 76 Federal Register 25590, 25592 (May 5, 2011).
131 See 2008 Rule, pp. 6-7, citing Bangs, et al. 2004, pp. 89-100; National Research Council 1997, pp. 185-186; Mech
and Peterson 2003, p. 159; Pletscher et al. 1991, pp. 545-548.
132 See FWS, Rocky Mountain Wolf Recovery Annual Reports (reporting that in 2010—199 cattle were killed by
wolves, and 260 wolves were killed (by either hunting or agency removal); in 2009—192 cattle were killed by wolves,
and 478 wolves were killed (by either hunting or agency removal); in 2008—184 cattle were killed by wolves, and 264
wolves were killed by agency removal; and in 2007—183 cattle were killed by wolves, and 186 wolves were killed by
agency removal), available at http://www.fws.gov/mountain-prairie/species/mammals/wolf/.
133 FWS, Rocky Mountain Wolf Recovery 2010 Interagency Annual Report Summary and Background (down from
1733 in 2009), available at http://www.fws.gov/mountain-prairie/species/mammals/wolf/annualrpt10/index.html.
134 Revision of Special Regulation for the Central Idaho and Yellowstone Area Nonessential Experimental Populations
of Gray Wolves in the Northern Rocky Mountains (hereinafter the “2008 Rule”). 73 Federal Register 4720 (January
28, 2008). See also 73 Federal Register 75356 (December 11, 2008) (reinstating the special rules).
135 2008 Rule, p. 8.
136 See annual reports at http://www.fws.gov/mountain-prairie/species/mammals/wolf/. According to FWS, at the time
of the 2008 Rule, Montana had 394 wolves, including 37 breeding pairs; Idaho had 788 wolves, including 41 breeding
pairs; and Wyoming had 362 wolves, including 27 breeding pairs. 2008 Rule, p. 11.
137 50 C.F.R. § 17.84(i)(7)(ii)(D).
138 2008 Rule, pp. 15-16.
139 75 Federal Register 65574 (October 16, 2010).
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In February 2011 FWS proposed to allow Idaho to kill some wolves across five years to help the
elk population rebound.140 The rule would modify the special rules for Ex Pops.
Author Contact Information
Kristina Alexander
M. Lynne Corn
Legislative Attorney
Specialist in Natural Resources Policy
kalexander@crs.loc.gov, 7-8597
lcorn@crs.loc.gov, 7-7267
140 76 Federal Register 7875 (February 11, 2011) (Notice of an environmental assessment with the preferred alternative
to reduce the approximately 76 wolves in the Lolo Elk Management Zone to 20-30 wolves for five years).
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