[Federal Register Volume 75, Number 104 (Tuesday, June 1, 2010)]
[Proposed Rules]
[Pages 30338-30363]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-12599]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R6-ES-2008-0053]
[MO 92210-0-0008-B2]


Endangered and Threatened Wildlife and Plants; 12-month Finding 
on a Petition to List the White-tailed Prairie Dog as Endangered or 
Threatened

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of a 12-month petition finding.

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SUMMARY: We, the U.S. Fish and Wildlife Service announce a 12-month 
finding on a petition to list the white-tailed prairie dog (Cynomys 
leucurus) as endangered or threatened under the Endangered Species Act 
of 1973, as amended. After a review of all available scientific and 
commercial information, we find that listing the white-tailed prairie 
dog is not warranted at this time. However, we ask the public to submit 
to us any new information that becomes available concerning the threats 
to the white-tailed prairie dog or its habitat at any time.

DATES: The finding announced in this document was made on June 1, 2010.

ADDRESSES: This finding is available on the Internet at http://www.regulations.gov at Docket Number FWS-R6-ES-2008-0053. Supporting 
documentation we used in preparing this finding is available for public 
inspection, by appointment, during normal business hours at the U.S. 
Fish and Wildlife Service, Utah Field Office, 2369 West Orton Circle, 
Suite 50, West Valley City, UT 84119. Please submit any new 
information, materials, comments, or questions concerning this finding 
to the above street address.

FOR FURTHER INFORMATION CONTACT: Larry Crist, Field Supervisor, Utah 
Field Office (see ADDRESSES); by telephone at 801-975-3330; or by 
facsimile at 801-975-3331. If you use a telecommunications device for 
the deaf (TDD), please call the Federal Information Relay Service 
(FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Background

    Section 4(b)(3)(B) of the Endangered Species Act of 1973, as 
amended (Act) (16 U.S.C. 1531 et seq.), requires that, for any petition 
to revise the Federal Lists of Endangered and Threatened Wildlife and 
Plants that contains substantial scientific or commercial information 
that listing the species may be warranted, we make a finding within 12 
months of the date of receipt of the petition. In this finding, we will 
determine that the petitioned action is: (1) Not warranted, (2) 
warranted, or (3) warranted, but the immediate proposal of a regulation 
implementing the petitioned action is precluded by other pending 
proposals to determine whether species are endangered or threatened, 
and expeditious progress is being made to add or remove qualified 
species from the Federal Lists of Endangered and Threatened Wildlife 
and Plants. Section 4(b)(3)(C) of the Act requires that we treat a 
petition for which the requested action is found to be warranted but 
precluded as though resubmitted on the date of such finding, that is, 
requiring a subsequent finding to be made within 12 months. We must 
publish these 12-month findings in the Federal Register.

Previous Federal Action

    On July 15, 2002, we received a petition dated July 11, 2002, from 
the Center for Native Ecosystems, Forest Guardians, Biodiversity 
Conservation Alliance, and Terry Tempest Williams, requesting that the 
white-tailed prairie dog (Cynomys leucurus) be listed as endangered or 
threatened across its entire range. We acknowledged the receipt of the 
petition in a letter to the petitioners, dated August 27, 2002. In that 
letter we also stated that higher priority actions precluded addressing 
the petition immediately, but it would be addressed when funding 
allowed.
    Section 4(b)(3)(B) of the Act requires that for any petition to 
revise the Lists of Threatened and Endangered Wildlife and Plants, to 
the maximum extent practicable, within 90 days after receiving the 
petition, we make a finding as to whether the petition presents 
substantial scientific or commercial information indicating that the 
petitioned action may be warranted. On November 9, 2004, we announced 
our 90-day finding (69 FR 64889) that the petition did not present 
substantial scientific or commercial information indicating that 
listing may be warranted. On July 12, 2007, in a Director's memorandum, 
the U.S. Fish and Wildlife Service (Service) announced that we would 
review the November 9, 2004, finding after questions were raised about 
the integrity of scientific information used and whether the decision 
was consistent with the appropriate legal standards. We received notice 
of a lawsuit from the Center for Native Ecosystems, and three other 
entities, on November 27, 2007, regarding our not-substantial 90-day 
finding. We agreed in a stipulated

[[Page 30339]]

settlement agreement on February 22, 2008, to submit a notice 
initiating a 12-month finding for the white-tailed prairie dog to the 
Federal Register on or before May 1, 2008, and to submit a 12-month 
finding for the white-tailed prairie dog to the Federal Register on or 
before June 1, 2010. Due to the stipulated settlement agreement, the 
petitioners dismissed the lawsuit on February 26, 2008. This notice 
constitutes the 12-month finding under the stipulated settlement 
agreement on the petition to list the white-tailed prairie dog as 
endangered or threatened.

Species Information

Species Description

    White-tailed prairie dogs are between 340 to 370 millimeters (mm) 
(13.4 to 14.6 inches (in)) in length with a 40- to 65-mm (1.6- to 2.6-
in) long tail (Clark et al. 1971, p. 1). The tail has a grayish white 
tip and is white on the terminal half. The coat is generally yellow-tan 
with distinctive dark brown or black cheek patches that extend above 
the eye with a lighter black stripe that extends below the eye onto the 
cheek (Clark et al. 1971, p. 1).

Taxonomy

    The white-tailed prairie dog is one of five prairie dog species 
that inhabit western North America (Clark et al. 1971, p. 1; Pizzimenti 
1975, pp. 62-63). Prairie dogs are in the squirrel family, Sciuridae, 
and belong to the genus Cynomys (Hollister 1916, p. 5). The genus is 
split into two subgenera; Leucocrossuromys includes prairie dogs with 
white tails and Cynomys includes prairie dogs with black tails. White-
tailed prairie dogs are included in the subgenus Leucocrossuromys along 
with Utah and Gunnison prairie dogs (Clark et al. 1971, p. 1; 
Pizzimenti 1975, pp. 15-16). Due to this consensus, we determined that 
the white-tailed prairie dog is a valid taxonomic species and a 
listable entity under the Act.

Ecology and Life History

    White-tailed prairie dogs occur at elevations ranging from 1,150 
meters (m) (3,773 feet (ft)) (Flath 1979, p. 63) to 3,200 m (10,500 ft) 
(Tileston and Lechleitner 1966, p. 295). Unlike the grass-dominated 
habitats of black-tailed prairie dogs, white-tailed prairie dogs 
inhabit drier landscapes with shrubland vegetation (Tileston and 
Lechleitner 1966, p. 295; Clark 1977, pp. 3-5; Collins and Lichvar 
1986, pp. 88-91; Gadd 2000, pp. 15-16). Their habitats are generally 
flat (Collins and Lichvar 1986, p. 92).
    Prairie dogs are primarily herbivorous and mainly eat grasses and 
forbs (Kelso 1939, pp. 7-11). However, they consume other plants 
seasonally. Prairie dog selection of plants is somewhat dependent on 
site-specific conditions and seasonality. For example, white-tailed 
prairie dogs eat sagebrush and saltbush during early spring, grasses in 
the summer, and seed heads and rabbitbrush flowers in the fall (Kelso 
1939, p. 10; Tileston and Lechleitner 1966, p. 302). White-tailed 
prairie dogs eat the least amount of grass of any prairie dog species 
and the most saltbush (Kelso 1939, p. 11). White-tailed prairie dogs 
also eat insects (Stockard 1929, p. 476). Prairie dogs obtain most of 
their water by eating vegetation and can become water-stressed if 
sufficient succulent vegetation is unavailable (Seglund et al. 2006, p. 
7).
    White-tailed prairie dogs prefer areas with lower vegetation 
heights (Collins and Lichvar 1986, p. 92), but they may use dense 
sagebrush adjacent to grassier areas (Tileston and Lechleitner 1966, p. 
314). White-tailed prairie dogs use the dense vegetation within 
sagebrush habitat to hide from predators (Hoogland 1981, pp. 266-268; 
Gadd 2000, pp. 24-26), reducing their need to visually search for 
predators and consequently reducing their need for dense colonies and 
cohesive social structures. This habitat use differs from black-tailed 
prairie dogs, who actively work to maintain the grassland vegetation 
surrounding their burrows for visibility.
    White-tailed prairie dogs dig their own burrows. Burrow 
construction requires deep, well-drained soils. Preferred soils are 
derived from sandstone or shale and may be clay-loam, silty clay, or 
sandy loam (Lupis et al. 2007, p. 6). Burrows are used throughout the 
year for hibernation, cover from temperature extremes, predator 
avoidance, and birthing and raising young (Clark 1977, p. 9; Hoogland 
1981, pp. 258-264). Burrow complexes are usually widespread with 
numerous entrances, tunnels, and chambers. The number of burrows in an 
area varies greatly from location to location, ranging from 0.12 to 
47.75 per hectare (ha) (0.3 to 118 per acre (ac)) with a mean of 0.32 
to 6.79 per ha (0.8 to 16.8 per ac) (Tileston and Lechleitner 1966, p. 
314; Menkens and Anderson 1989, p. 84; Seglund and Schnurr 2009, p. 
94).
    For purposes of this finding, a group of burrows is referred to as 
a colony. A complex is a collection of colonies grouped on the 
landscape. There is usually a high degree of connectivity between 
colonies in the same complex.
    White-tailed prairie dog colonies have fewer animals per unit area 
with less obvious borders than black-tailed prairie dog colonies 
(Tileston and Lechleitner 1966, pp. 297, 314; Hoogland 1981, p. 252). 
Home range sizes range from 0.2 to 1.9 ha (0.5 to 4.7 ac) (Clark 1977, 
p. 65; Cooke 1993, p. 23), which are generally larger than black-tailed 
prairie dog home ranges (Clark 1977, p. 65).
    White-tailed prairie dogs can live up to 8 years in captivity but 
may not live past 4 years in the wild (Pauli et al. 2006, p. 18). 
Prairie dog annual mortality rates average 30 to 60 percent, largely 
due to disease and predation (Tileston and Lechleitner 1966, p. 305; 
Clark 1977, pp. 80-81).
    Adult sex ratios are approximately one male to two females (Clark 
1977, p. 76; Hoogland 2010, pers. comm.). White-tailed prairie dogs can 
reproduce at 1 year of age, and they have a single litter once a year 
averaging four to five pups (Bakko and Brown 1967, pp. 110-111). 
Breeding occurs from late March to mid-April (Tileston and Lechleitner 
1966, p. 303). Pups are born in the burrows after a gestation period of 
approximately 30 days (Tileston and Lechleitner 1966, p. 304), and 
emerge from the burrow for the first time 4 to 6 weeks after birth 
(Bakko and Brown 1967, p. 103). They begin to disperse from the colony 
in June and July when population densities are the highest (Clark 1977, 
p. 72). Migration is recognized as an important factor to white-tailed 
prairie dog population dynamics (Clark 1977, p. 80). Plague in this 
species often results in near extirpation of colonies. Rapid 
recolonization of some areas post-plague with few or no surviving 
reproductive adults suggests the species is highly mobile (Seglund et 
al. 2006, p. 10). Dispersal distances of up to 8 kilometers (km) (4.8 
miles (mi)) have been observed (Cooke 1993 in Seglund et al. 2006, p. 
10)
    White-tailed prairie dogs have the least cohesive social structure 
of any prairie dog species. Their social system is organized around 
family groups or ``clans,'' comprised of several reproductive females, 
one or two males of reproductive age, and dependent young (Clark 1977, 
p. 62; Cooke 1993, p. 22). Adult white-tailed prairie dogs spend little 
time displaying social behavior, and most of their time feeding or in 
alert postures (Clark 1977, p. 44). Pups spend a large amount of time 
playing during their first few weeks (Tileston and Lechleitner 1966, p. 
300).
    White-tailed prairie dog populations exhibit large fluctuations of 
more than

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50 percent from year to year (Menkens and Anderson 1989, p. 345). 
Population fluctuations are likely due to disease cycles, vegetation 
quantity and quality, and drought (Seglund and Schnurr 2009, p. 16) 
(see Factor A. Climate Change; Factor C. Disease). We do not know the 
level at which population fluctuations are a natural part of white-
tailed prairie dog ecology, or the result of environmental or human-
caused threat factors. In many cases, prairie dog colonies persist 
despite large population fluctuations (see Factor C. Disease). We 
define ``persistence'' as the long-term continuance of white-tailed 
prairie dog colonies, at a high enough level to exist in the long-term 
with minimal management assistance.
    White-tailed prairie dogs are diurnal (active during the day) 
(Tileston and Lechleitner 1966, p. 200). They are active approximately 
5 to 7 months per year from early spring to fall and hibernate during 
late fall and winter (Clark 1977, pp. 59-60; Cooke 1993, p. 11). Time 
spent hibernating is determined by available food resources (Clark 
1977, p. 60). In warm weather, even in mid-winter, white-tailed prairie 
dogs will feed if grasses are growing (Hollister 1916, p. 6; Goodrich 
and Buskirk 1998, p. 177). If resources are not sufficient, prairie 
dogs become inactive and spend more time in their burrows (Harlow and 
Menkens 1986, p. 795). During periods of high summer temperatures, 
white-tailed prairie dogs avoid the highest temperatures of midday by 
foraging in the cooler morning and evening hours (Clark 1977, p. 58).

Distribution and Abundance

    The overall species' distribution is mapped as ``gross range.'' The 
available white-tailed prairie dog literature uses the term ``gross 
range'' to describe the outer boundary identifying the overall 
rangewide distribution of the white-tailed prairie dog (Figure 1). 
However, not all lands within the species' gross range are occupied or 
have the potential to be occupied by white-tailed prairie dogs (Seglund 
et al. 2006, p. 100). The predicted range is a subset of the gross 
range and thus represents a more accurate spatial representation of the 
potential range of the white-tailed prairie dog (Seglund et al. 2006, 
pp. 16, 110; Seglund and Schnurr 2009, p. 23). Predicted range is 
defined using habitat characteristics of vegetation, land use, slope, 
and elevation (Seglund et al. 2006, pp. 14-39). Depending on available 
data, we use gross range, predicted range, or mapped occupied habitat 
throughout this document to evaluate status and threats to the species. 
For example, gross range mapping data was available for our use for all 
States across the species' range. However, the data for the predicted 
range map (Seglund et al. 2006, p. 110; Seglund and Schnurr 2009, p. 
23) was only available for the State of Colorado. Information regarding 
mapped occupied habitat (all areas mapped on Federal lands as occupied 
by white-tailed prairie dogs since 1985) was available for the State of 
Utah, but not for any other States.
BILLING CODE 4310-55-S

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[GRAPHIC] [TIFF OMITTED] TP01JN10.000

BILLING CODE 4310-55-C

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    The white-tailed prairie dog occurs from a small area in south-
central Montana, throughout much of Wyoming, into western Colorado, and 
northeastern Utah. There are 20,224,801 ha (49,976,572 ac) within the 
gross range of the white-tailed prairie dog and 13,066,887 ha 
(32,288,981 ac) within the species' predicted range (Seglund et al. 
2006, p. 91). Therefore, approximately 65 percent of the gross range 
has the characteristics necessary to support the white-tailed prairie 
dog. Wyoming contains the largest amount of white-tailed prairie dog 
predicted range (75 percent) (Knowles 2002, p. 4). Less than 1 percent 
of predicted range occurs in Montana (Table 1). The majority of white-
tailed prairie dog predicted range (56 percent) occurs on land managed 
by the Bureau of Land Management (BLM). A significant portion of the 
predicted range occurs on private land (37 percent). Very little of the 
predicted range is managed by the Service (0.4 percent), U.S. Forest 
Service (USFS) (0.5 percent), or National Park Service (NPS) (0.9 
percent) (Table 1).

                 TABLE 1. Percent Predicted Range by State and Land Management Entity (Seglund et al. 2006, pp. 91, 98, 100, 104, 109).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                           Total Range     Private         BLM          USFS           NPS          USFWS         State         Other
--------------------------------------------------------------------------------------------------------------------------------------------------------
Colorado                                           11            37            56           < 1             1           < 1             5           < 1
--------------------------------------------------------------------------------------------------------------------------------------------------------
Montana                                       < \*\ 1            49            44             2             0             0             5           < 1
--------------------------------------------------------------------------------------------------------------------------------------------------------
Utah                                               13            20            60           < 1           < 1           < 1            11             7
--------------------------------------------------------------------------------------------------------------------------------------------------------
Wyoming                                            75            33            54           < 1           < 1           < 1             6             6
--------------------------------------------------------------------------------------------------------------------------------------------------------
Total                                                            37            56           < 1           < 1           < 1             5           < 1
--------------------------------------------------------------------------------------------------------------------------------------------------------
* < less than

    Historical abundance and distribution are not well documented for 
white-tailed prairie dogs prior to the 1980s (Pauli et al. 2006, p. 13; 
Seglund et al. 2006, p. 11). The distribution of white-tailed prairie 
dogs has not changed appreciably since historic times (Knowles 2002, 
pp. 5-6). The only recorded change in distribution is in Montana, where 
white-tailed prairie dogs were previously captured 40 miles north of 
currently occupied habitat (Knowles 2002, p. 5). However, abundance 
declined as a result of past control efforts and plague (Cully 1993, p. 
38; Knowles 2002, pp. 1-2) (see Factor B. Overutilization and Factor C. 
Disease). We are not able to quantify changes in occupied habitat for 
the species because mapping did not use standardized methods, and we do 
not have accurate estimates of historical occupied habitat (Seglund et 
al. 2006, p. 13).
    We do not have rangewide population trend information due to a lack 
of historical population information and inconsistencies in survey 
methodologies (Seglund et al. 2006, pp. 4, 13). Surveys for white-
tailed prairie dog distribution and occupancy rates were recently 
conducted across portions of the species' gross range (Grenier and 
Filipi 2009, entire; Seglund and Schnurr 2009, p. 27; Wright 2009, 
entire). While occupancy surveys are intended to determine population 
trends (Seglund and Schnurr 2009, p. 10), the data are not yet 
available to provide trend information. In addition, each State used 
different methods to conduct ground surveys and determine occupancy 
rates; thus, the results are not comparable. We present State-by-State 
information below with the caveat that comparing colony occupancy rates 
across the gross range of the species is not possible.
Colorado
    White-tailed prairie dog predicted range includes Moffat, Routt, 
Rio Blanco, Garfield, Mesa, Delta, Montrose, Eagle, Jackson, Ouray, and 
Larimer Counties in northwestern Colorado (Seglund et al. 2004, p. 
133). Approximately 1,246,441 ha (3,104,733 ac) of predicted white-
tailed prairie dog habitat occurs in three Individual Population Areas 
(IPAs): Grand Valley-Uncompahgre IPA, North IPA, and Northwest IPA 
(Hotze 2010, pp. 9-10). An IPA is an area physically separated from 
other populations that may face a unique subset of threats (Seglund and 
Schnurr 2009, p. 1). These population areas are geographically 
separated from each other but connected to population areas in Utah and 
Wyoming (Seglund and Schnurr 2009, p. E-5).
    Colorado completed Statewide white-tailed prairie dog surveys in 
2004 and 2008; occupancy rates were 24.1 and 23.1 percent, 
respectively, a statistically insignificant difference (Seglund and 
Schnurr 2009, pp. 27-28). Occupancy rate is the number of randomly 
selected plots in predicted habitat with prairie dogs, and is not a 
measure of abundance. We do not have population trend information 
across the entire predicted range of the species in Colorado. Localized 
declines and habitat degradation were reported in the Grand Valley-
Uncompahgre IPA due largely to urbanization (Seglund and Schnurr 2009, 
p. 54). Information in the North IPA is restricted to colonies 
associated with black-footed ferret reintroduction; a historical record 
of ferrets in this area suggests it once supported abundant populations 
of prairie dogs (Seglund and Schnurr 2009, p. 58). Only two colonies 
remain, although they have remained stable for the past 20 years 
(Seglund and Schnurr 2009, p. 58). Population densities and 
distribution in the Northwest IPA appear to fluctuate greatly in large 
part due to the prevalence of plague (Seglund and Schnurr 2009, pp. 63-
76).
Montana
    White-tailed prairie dogs occur in one population area in Carbon 
County, along the Montana-Wyoming border (Seglund et al. 2006, p. 25). 
Fifteen colonies were mapped in the 1970s across 312.8 ha (773 ac) 
(Flath 1979, p. 63). White-tailed prairie dogs were previously reported 
in north Sage Creek in Carbon County (Hollister 1916, p. 27), and in 
Yellowstone County just northeast of Carbon County (Kelso 1939, p. 7), 
but no animals were found in these locations in later surveys (Flath 
1979, entire).
    Current occupied area of white-tailed prairie dogs in Montana 
includes 112 ha (277 ac) across 11 colonies; 8 colonies were considered 
active in 2009 (MFWP 2009a, p. 1). The apparent loss in occupied 
habitat is likely due to plague and agricultural land conversion (Parks 
et al. 1999 in Knowles 2002, p. 15). We do not have population trend 
data for the white-tailed prairie dog in Montana.

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Utah
    White-tailed prairie dogs occur in Rich, Summit, Daggett, Uintah, 
Duchesne, Carbon, Emery, and Grand Counties (Seglund et al. 2004, p. 
140) in northern and eastern Utah. In 2002 and 2003, 57,463 ha (141,808 
ac) of occupied white-tailed prairie dog habitat were documented, 
mostly within Uintah and Duchesne Counties (Lupis et al. 2007, p. 17). 
Smaller population areas are found in the Cisco Desert in Emery and 
Grand Counties (10,869 ha (26,856 ac)), and in Rich County (73 ha (180 
ac)) (Lupis et al. 2007, p. 15). Surveys did not include private lands; 
therefore, the amount of occupied habitat is an underestimate. These 
population areas are mostly disconnected from each other, but connect 
to population areas in Wyoming and Colorado. Based on surveys conducted 
in 2008, the white-tailed prairie dog occupancy rate was 46 percent of 
sampled plots (Wright 2009, p. 5).
    We do not have information on long-term population status or trends 
for white-tailed prairie dogs in Utah. Surveys in black-footed ferret 
management areas in the Uintah basin recorded fluctuating population 
levels: increasing densities since the early 1990s, declines in 1999 
and 2003, and population recoveries in 2004-2008 (Seglund et al. 2006, 
p. 28; Maxfield 2009, pers. comm.) (see Factor A. Climate Change).
Wyoming
    White-tailed prairie dogs are found in the Counties of Big Horn, 
Park, Hot Springs, Natrona, Fremont, Sublette, Sweetwater, Lincoln, 
Uinta, Carbon, and Albany in northern and southern central Wyoming 
(Seglund et al. 2004, p. 130). Wyoming Fish and Game documented 
11,511,356 ha (27,822,847 ac) of potential habitat and 1,170,952 ha 
(2,893,487 ac) of occupied habitat in 2008 by aerial survey (Grenier 
and Filipi 2009, p. 5). The majority of these acres are in Albany and 
Carbon Counties. Habitat in Wyoming is mostly continuous and not split 
into discrete population areas. Approximately 68 percent of the 
surveyed areas were estimated to be occupied (Grenier and Filipi 2009, 
p. 5). This estimate is not a statistically determined ``occupancy 
rate.'' Occupancy from these aerial surveys cannot be compared with 
ground surveys from Colorado and Utah, because the observed location of 
colony boundaries varies between methods, presumably due to the 
difficulty in measuring colony boundaries from the air (Andelt et al. 
2005, p. 3). We do not have long-term status or trend information for 
white-tailed prairie dogs in Wyoming.
Summary of White-Tailed Prairie Dog Population Status
    We do not have reliable long-term historical or current white-
tailed prairie dog status, trend, or distribution data. White-tailed 
prairie dog populations are likely below historical levels, though 
their overall distribution has not substantially changed (Knowles 2002, 
p. 6). Large acreages of occupied habitat exist across the species' 
range, particularly in Wyoming. Each State plans to continue occupancy 
surveying, so more information may be available in the future.

Evaluation of Information Pertaining to the Five Threat Factors

    Section 4 of the Act and implementing regulations (50 CFR 424) set 
forth procedures for adding species to, removing species from, or 
reclassifying species on the Federal Lists of Endangered and Threatened 
Wildlife and Plants. Under section 4(a)(1) of the Act, a species may be 
determined to be endangered or threatened based on any of the following 
five factors:
    (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range;
    (B) Overutilization for commercial, recreational, scientific, or 
educational purposes;
    (C) Disease or predation;
    (D) The inadequacy of existing regulatory mechanisms; or
    (E) Other natural or manmade factors affecting its continued 
existence.
    In making this 12-month finding, information pertaining to the 
white-tailed prairie dog in relation to the five factors provided in 
section 4(a)(1) of the Act is discussed below. In making our 12-month 
finding on the petition we considered and evaluated the best available 
scientific and commercial information.

Factor A. The present or threatened destruction, modification, or 
curtailment of the species' habitat or range.

    The following potential factors that may affect the habitat or 
range of the white-tailed prairie dog are discussed in this section, 
including: (1) Oil and gas exploration and development, (2) oil shale 
and tar sands development, (3) mineral development, (4) renewable 
energy development--wind and solar, (5) urbanization, (6) agricultural 
land conversion, (7) grazing, (8) fire occurrence and suppression, (9) 
invasive plant species and (10) climate change.
Oil and Gas Exploration and Development
    Exploration and development of oil and gas resources is widespread 
throughout the gross range of the white-tailed prairie dog (Hotze 2010, 
pp. 11-26). Between 2004 and 2008, exploration of oil and gas in the 
intermountain west increased substantially because of political and 
economic incentives (National Petroleum Council 2007, pp. 5-7). The 
2005 Energy Policy Act expedited the leasing and permitting process on 
Federal lands (42 U.S.C. 15801). The global recession of 2008 resulted 
in decreased energy demand resulting in a reduced rate of energy 
development. Fossil fuel production is expected to regain and surpass 
the early 2008 levels in 2010-2030 (Copeland et al. 2009, p. 1; Energy 
Information Administration (EIA) 2009, p. 109).
    Energy development includes exploration, drilling, production, and 
reclamation phases (Tribal Energy and Environmental Information 
Clearinghouse (TEEIC) 2009, entire), each of which may potentially 
impact the white-tailed prairie dog or its habitat. During the 
exploration phase, oil and gas resources are delineated using a variety 
of technologies, including seismic shot-hole surveys (planting and 
detonation of underground explosives to produce vibrations that reveal 
locations of mineral resources) and vibroseis trucks (vehicle with a 
vibration plate used to survey mineral resources) (TEEIC 2009, p. 6). 
These activities may result in mortality and the crushing of vegetation 
along the seismic route, but there are no permanent structures 
established during the exploration phase. If oil and gas resources are 
proven, the lessee moves into the drilling phase. During the drilling 
phase, access roads and well pads are constructed, pipelines are 
installed, and the infrastructure necessary for the production phase 
(such as compressor stations) is developed and constructed (TEEIC 2009, 
p. 9). This phase typically results in longer-term disturbance to 
white-tailed prairie dog habitat. The production phase includes 
maintaining the wells and infrastructure as well as continuing the 
extraction of the oil and gas resources. Wells may be in the production 
phase for up to 20 to 30 years for gas wells (TEEIC 2009, p. 5) and up 
to 100 years for oil wells (Connelly et al. 2004, p. 7:41). The final 
phase begins when a well is no longer producing oil or gas because the

[[Page 30344]]

resource is depleted. The lessee is responsible for reclaiming the land 
back to its original condition, or as close to the original condition 
as possible (BLM 2007a, p. 2; TEEIC 2009, p. 15).
    Oil and gas developments are typically configured as point (e.g., 
well pads, compressors) and line (e.g., roads, pipelines) disturbances 
across broad areas. The amount of direct habitat loss may encompass 5 
to 10 percent of leased areas. However, the extent of disturbance to 
white-tailed prairie dogs may reach far beyond the direct habitat loss, 
due to the loss and fragmentation of habitats; the alteration of 
vegetation resources, which often promotes nonnative invasive plant 
species; increased noise levels; increased vehicle traffic; and 
increased human access to previously remote areas (Pauli et al. 2006, 
p. 27; Seglund et al. 2006, p. 46; Seglund and Schnurr 2009, p. 126; 
Wyoming Game and Fish Department (WGFD) 2009, p. 10). The amount of 
direct habitat loss and total fragmentation varies greatly depending on 
well density (number of acres per well) and spacing (distance between 
individual well pads). Increasing wells per unit area decreases the 
amount of habitat available for wildlife. Well densities and spacing 
are typically designed to maximize recovery of the resource and are 
administered by State oil and gas agencies and the BLM on Federal 
mineral estate. Each geologic basin has a standard spacing, but 
exemptions are granted (Connelly et al. 2004, pp. 7-39 to 7-40). Within 
the range of the white-tailed prairie dog, well spacing can vary from 5 
to 160 acres per well. Larger well spacing is often characterized by 
more wells drilled per pad. Increasing the number of wells per pad 
increases the size of the individual pad but decreases the amount of 
habitat fragmented. The variation in well and well pad spacing results 
in a variation in the intensity of effects across the species' range. 
However, we are unable to determine how the ultimate effects to the 
species vary with well density. The threshold levels of oil and gas 
development that result in reduced populations or eliminated colonies 
are unknown.
    Resulting impacts to white-tailed prairie dogs from oil and gas 
development may include direct mortality from vehicles; direct 
mortality associated with increased access by recreational shooters who 
utilize the new access routes (Gordon et al. 2003, p. 12); increased 
disturbance responses from increased human activity; direct loss of 
habitat and forage resources during exploration, drilling, and 
production; and indirect loss of forage resources from invasive, 
nonnative plant species (Seglund and Schnurr 2009, p. 126).
    No studies have been done regarding the short-term or long-term 
impact of oil and gas development on individual white-tailed prairie 
dogs or their colonies. White-tailed prairie dogs can be negatively 
impacted by the direct loss of habitat that occurs as a result of 
development. For example, white-tailed prairie dog burrow densities 
were lower at well locations compared to areas further from the well 
pads (Biggins et al. 1984, p. 12). Dead prairie dogs were found in oil 
and gas reserve pits (Esmoil 1995 in Peterson 2008, p. 5), although the 
extent of population level impact is not known. The use of vibroseis 
trucks in prairie dog colonies appears to impact vegetation, but 
preliminary results did not document prairie dog mortality or burrow 
collapse (Young and Sawyer 1981, pp. 1-2; Menkens and Anderson 1985, p. 
7).
    However, as described above, exposure to a factor does not 
necessarily indicate that the factor is a threat. We know that white-
tailed prairie dog colonies exist in areas with long-term oil and gas 
development. Some of the largest and most robust colonies are located 
near areas of intense oil and gas development (see Distribition and 
Abundance, above, and our discussion under Factor C, below). For 
example, the Coyote Basin, Kennedy Wash, and Snake John colonies in 
Uintah County, Utah, occur within a landscape fragmented by oil and gas 
infrastructure, although their immediate occupied habitats have not 
sustained significant energy development. Fifty percent of the mapped 
occupied habitat in this region has been leased with 17 percent 
currently producing (See Utah, below). Populations in this area have 
fluctuated; although this has been attributed to drought (See Climate 
Change, below). Despite the high amount of leasing in this area, 
populations have recovered to their 20 year recorded peak. Similarly, 
Coyote Basin and Wolf Creek are historically Colorado's most robust 
colonies and occur within the Northwest IPA where oil and gas 
development is high. Forty one percent of this IPA has already been 
leased, with 7 percent currently producing (Hotze 2010, p. 20). Prairie 
dogs continue to occupy a moderately sized complex within the Coal Oil 
Basin (Colorado's largest oil field) despite an active drilling history 
that extends back to 1944 (Wolf Creek Work Group 2001, p. 15).
    Available information does not indicate that white-tailed prairie 
dogs are currently reacting to oil and gas activities on a local 
landscape scale or at the population or species level. We also do not 
know if there is a level of oil and gas development at which the status 
of prairie dogs at the population or species level would be negatively 
impacted. As described above, white-tailed prairie dogs persist in 
several areas with oil and gas activity.
    To evaluate the extent to which oil and gas development may affect 
white-tailed prairie dogs in the foreseeable future, we overlaid BLM-
authorized oil and gas leases with the species' gross range. More 
specific information was available for Utah and Colorado, so we 
overlaid oil and gas development with white-tailed prairie dog 
predicted range (Seglund and Schnurr 2009, p. 24) in Colorado and 
mapped occupied habitat in Utah (Hotze 2010, p. 7). We also reviewed 
information on State-specific potential oil and gas reserves where that 
information was available. The results are presented below and in the 
State-by-State analysis sections.
    In additional to managing lands in Wyoming, Colorado, and Utah, the 
BLM manages the Federal mineral estate, including authorizing oil and 
gas leases. Leases may be producing or non-producing. Producing leases 
are those being actively developed. Non-producing leases are leased; 
however, the resources for which they were leased are not currently 
being extracted. Non-producing leases may become developed in the 
future, but development is not guaranteed (Thompson 2010, pers. comm.). 
We consider these leases to be indicative of potential development. 
However, we do not know the percent of non-producing leases that will 
become developed in the future because the variables governing 
development are complex and include the price of gas, the number of 
other leases the company holds, the actual amount of resource the lease 
contains (often unknown at the time of lease), and other complex 
economic and social factors.
    In addition to the producing and non-producing leases, BLM has 
authorized a significant amount of the Federal mineral estate that may 
be leased in the future. Each BLM field office developed a resource 
management plan that delineates areas available for leasing and depicts 
surface access constraints (e.g., BLM 2008a, p. 7). The areas that are 
available for leasing are larger than those that have already been 
authorized, and include areas that may be developed in the future 
should proven reserves be located. Development of the entire area 
available for leasing is unlikely due to BLM's multi-use mandate, but 
the area available for

[[Page 30345]]

leasing represents a potential maximum of oil and gas development. Non-
Federal mineral estates are managed by State, tribal, and private 
mineral rights owners under different programs and using different 
processes.
    We were unable to specifically quantify the impacts of development 
on non-Federal mineral rights. Total active and plugged wells are 
available as GIS layers from each State's oil and gas development 
commission. However, number of wells is not a biologically meaningful 
measure to the white-tailed prairie dog because the effects depend on 
the amount of land leased and well density and spacing. As previously 
stated, the impacts to the species at different well spacing densities 
are not well understood. Approximately two-thirds of wells within the 
species range are located on Federal versus non-Federal estate (BLM 
2009; Colorado Oil and Gas Conservation Commission 2010; Wyoming Oil 
and Gas Conservation Commission 2010; Utah Division of Oil and Mining 
2010; unpublished data). Similarly, approximately two-thirds of the 
species range is in Federal vs. non-Federal ownership. We assume that a 
similar ratio of development of non-Federal minerals is likely to occur 
in the future as is occurring for Federal minerals. Because leasing 
does not guarantee development, and the fact that we are unable to 
estimate leasing rates on non-Federal estate, we consider the numbers 
presented below (in the State-by-State analysis) as an approximate 
measurement of Federal and non-Federal development that could occur in 
the foreseeable future.
    The BLM has authorized 5,687,259 ha (14,053,523 ac) of producing 
and non-producing leases for oil and gas development, representing 
approximately 28 percent of the white-tailed prairie dog's gross range 
(Hotze 2010, p. 18). Producing leases occur across 1,435,580 ha 
(3,547,395 ac), or 7 percent, of the species' gross range (Hotze 2010, 
p. 18). Future exploration and development of fossil fuels is likely to 
focus in areas of highest potential return. Highest potential return is 
defined by several geological characteristics including permeability 
and porosity of the underlying rock (BLM 2005a, p. 41). For example, in 
the BLM Little Snake field office of northwest Colorado, approximately 
96 percent of new wells will be drilled in areas with high oil and gas 
potential (BLM 2007b, p. 3:100). In high and moderate potential areas 
in Wyoming, a single well can produce 4 to 30 times as much as a well 
in low potential areas (BLM 2008b, p. A20:6). Therefore, we assume 
these areas will be the focus of future leasing.

Colorado

    In Colorado, the BLM authorized oil and gas leases on 30 percent of 
the white-tailed prairie dog's predicted range in the State (Hotze 
2010, p. 20) across the Northwest, North, and Grand Valley-Uncompahgre 
IPAs. Of the authorized oil and gas leases within the predicted range 
in Colorado, there are 61,334 ha (151,560 ac) of producing leases, 
which comprise approximately 5 percent of the predicted State range 
(Hotze 2010, p. 14). Non-producing leases encompass 311,650 ha (770,104 
ac), or approximately 25 percent of the predicted State range (Hotze 
2010, p. 14).

Northwest Individual Population Area (IPA)

    The Northwest IPA in Moffat and Rio Blanco Counties is within the 
Greater Green River Basin (DOI et al. 2006, p. 20) and has the highest 
potential for oil and gas development (Seglund and Schnurr 2009, p. 
61). This IPA comprises approximately 54 percent of white-tailed 
prairie dog predicted habitat in Colorado (Hotze 2010, p. 10). 
Authorized lease areas in 2009 encompassed approximately 41 percent of 
the Northwest IPA (Hotze 2010, p. 20), and oil and gas development is 
projected to significantly increase over the next 20 years (Seglund and 
Schnurr 2009, p. 128). For example, the BLM anticipates authorizing the 
drilling of 3,031 oil and gas wells over the next 20 years in Routt and 
southwestern Moffat Counties (BLM 2007b, p. 3:100), whereas the 
previous 20 years resulted in 594 drilled wells (BLM 2007b, p. 3:99). 
Similarly, the BLM anticipates between 17,800 and 21,200 new wells will 
be drilled over the next 20 years in Rio Blanco and central and 
northern Moffat Counties, whereas there were 5,800 wells drilled 
previously (Seglund and Schnurr 2009, p. 129). However, the majority of 
these wells will occur outside of the white-tailed prairie dog's 
predicted range (Seglund and Schnurr 2009, p. 129). Approximately 96 
percent of new wells will be drilled in areas with high oil and gas 
potential as defined by the BLM (2007b, p. 3:100); we believe this 
localizes the development to some extent and thus limits the amount of 
prairie dog habitat impacted.
    Three potential coal bed methane areas partially overlap white-
tailed prairie dog habitat in the Northwest IPA: eastern Sand Wash 
Basin, Lower White River, and Danforth Hill (BLM 2007b, p. 3:102). 
However, the majority of the coal bed methane areas occur outside the 
predicted range for the species within Colorado (BLM 2007b, Figure 3-
16; Seglund and Schnurr 2009, p. 119).

Grand Valley-Uncompahgre IPA

    There is potential for energy development to occur in a corridor of 
the Grand Valley-Uncompahgre IPA in Mesa, Montrose, and Ouray Counties 
(Seglund and Schnurr 2009, p. 54). Approximately 14 percent of the 
white-tailed prairie dog's predicted range in this IPA is authorized 
for lease or contains pending leases from the BLM (Seglund and Schnurr 
2009, p. 131; Hotze 2010, p. 20). The BLM estimates authorizing 3,600 
wells on 1,519 pads over the next 20 years in this IPA (Ewing 2009, 
pers. comm.). The total area disturbed is estimated at 13,200 ac (5,342 
ha) of short-term disturbance and 4,100 ac (1,659 ha) of long-term 
disturbance (Ewing 2009, pers. comm.). We do not know where this 
development will occur with respect to known prairie dog colonies. 
However, 85 percent of this IPA remains unleased, and future wells 
represent a relatively small (less than 2 percent of this IPA) amount 
of additional disturbance.

North IPA

    Crude oil was historically produced in the North IPA to a limited 
degree. However, EOG Resources discovered a large reservoir of crude 
oil in this area in 2008, and subsequently acquired a lease for 100,000 
ac (40,469 ha) of land in the area (Seglund and Schnurr 2009, p. 129). 
Approximately 25 percent of the white-tailed prairie dog's predicted 
range in the North IPA has authorized or pending leases (Seglund and 
Schnurr 2009, p. 131; Hotze 2010, p. 20).
    In summary, BLM has authorized and has pending leases on 
approximately 30 percent of the predicted range of the species within 
Colorado for oil and gas development (Seglund and Schnurr 2009, p. 131; 
Hotze 2010, p. 20). The largest potential for overlap and impacts to 
white-tailed prairie dogs occurs in the Northwest IPA; oil and gas 
development is projected to increase substantially in this IPA over the 
next 20 years (Seglund and Schnurr 2009, p. 129). We expect the 
majority of future oil and gas development to occur in this IPA. We do 
not know the exact locations of energy development facilities with 
respect to locations of white-tailed prairie dog colonies. Oil and gas 
development will likely impact white-tailed prairie dogs, causing 
individual mortalities and habitat loss and fragmentation. However, the 
majority of oil and gas development will occur in

[[Page 30346]]

areas of high potential energy reserves, and particularly in the 
Northwest IPA, so impacts to the species are likely to be more 
localized, and are not expected to occur at high levels across the 
species' predicted range in Colorado. Based on the available 
information, we do not believe oil and gas development in Colorado is a 
threat to the species now or in the foreseeable future.

Montana

    White-tailed prairie dog habitat in Montana represents less than 1 
percent of the gross range of the species (Seglund et al. 2006, p. 91), 
and is contained entirely within Carbon County. Therefore we did not 
calculate the area impacted by oil and gas leasing. The area containing 
the South Sage Creek white-tailed prairie dog colony was leased in 
January 2002, but is not yet developed (Begley 2010a, pers. comm.). The 
South Sage Creek colony occupies less than 6 ha (15 ac), or 5 percent 
of the occupied habitat in Montana (MFWP 2009b, p. 3). The area 
containing the Robertson Draw colony is available for leasing but has 
not yet been leased (Begley 2010a, pers. comm.). Oil and gas 
development is not impacting the remaining six colonies in Montana 
(Seglund et al. 2006, p. 26). Because of the small amount of habitat 
impacted, oil and gas development is not a significant threat in this 
State, now or in the foreseeable future.

Utah

    The BLM has authorized oil and gas leases on 31 percent of the 
white-tailed prairie dog's gross range in Utah (Hotze 2010, p. 18). The 
highest overlap between the gross range of the white-tailed prairie dog 
and oil and gas development potential occurs in Uintah, Duchesne, 
Grand, and Carbon Counties (Hotze 2010, pp. 21-22; Utah Department of 
Natural Resources 2004 in Seglund et al. 2006, p. 33).
    The Uinta and Piceance Basin areas of Utah have significant oil and 
gas resources (BLM 2008a, p. 3:38). Approximately 82 percent of 18,982 
existing well locations in Utah occur in the Uinta Basin in Duchesne 
and Uintah Counties (Hotze 2010, pp. 15-16). There are 97,266 ha 
(240,350 ac) of mapped occupied white-tailed prairie dog habitat in 
Uinta and Duchesne Counties (Hotze 2010, pp. 7-8). The BLM has 
authorized oil and gas leasing on approximately 51 percent of this 
mapped occupied habitat (Hotze 2010, p. 22). The BLM estimates that 
approximately 2,055 new oil wells, 4,345 new gas wells, and 130 new 
coal bed methane wells will be drilled within the Uinta Basin during 
the 15- to 20-year planning period (BLM 2008a, p. 3:36). Approximately 
73 percent of the Federal mineral rights open to leasing in the Uinta 
Basin area have already been authorized (Hotze 2010, p. 24). Therefore, 
the authorized leases represent a fair assessment of the potential 
impact to white-tailed prairie dogs. These leases have a 201-meter 
(660-ft) no surface occupancy stipulation adjacent to occupied prairie 
dog colonies, which will minimize direct mortality of prairie dogs and 
the loss of habitat from future development (see Factor D. Inadequacy 
of Regulatory Mechanisms, below, for a discussion of these 
stipulations).
    There are 14627 ha (36,144 ac) of mapped white-tailed prairie dog 
habitat in Carbon and Emery Counties (Hotze 2010, p. 8). The BLM has 
authorized oil and gas leasing on approximately 52 percent of this 
occupied mapped habitat (Hotze 2010, p. 22). About 2300 ha (5,600 ac) 
(15 percent) of this habitat is located within areas considered to have 
high potential for oil and gas resources (BLM 2004, p. 4:119). These 
leases also have a no surface occupancy stipulation for prairie dog 
colonies (see Factor D).
    In summary, oil and gas leasing and development is authorized by 
BLM across 31 percent of the species' gross range in Utah. The majority 
of current and future project development occurs in the Uinta Basin in 
northeastern Utah, and thus potential impacts to the species could be 
greatest in this area, particularly because 52 percent of the species' 
mapped occupied habitat is leased. We consider the Uinta Basin to be 
the highest potential development area in Utah. Exploration and 
drilling, as previously discussed, can result in mortality of 
individual prairie dogs and the loss and fragmentation of habitats. 
However, robust white-tailed prairie dog colonies continue to persist 
in the Uinta Basin, in areas associated with existing oil and gas 
development. The BLM imposes a no surface occupancy stipulation that 
prohibits activity within 201 meters (660 ft) of white-tailed prairie 
dog colonies in the Uinta Basin (see Factor D), which will minimize 
direct mortality of prairie dogs and the loss of habitat from future 
development. The likely concentration of oil and gas development in 
high potential resource areas should also minimize the amount of white-
tailed prairie dog habitat directly lost to development. Due to these 
factors, we do not believe oil and gas development in Utah is a threat 
to the species now or in the foreseeable future.

Wyoming

    Seventy-seven percent of the species' gross range in Wyoming 
overlaps potential energy resources in Wyoming (Seglund et al. 2006, p. 
39). However, not all potential energy resources will be developed. 
Therefore, we further reviewed leases and potential energy resources to 
determine the extent of development in the foreseeable future (the next 
20 years).
    Approximately 3,443,269 ha (88,508,503 ac) of land, or 27 percent 
of the species' gross range in Wyoming, is authorized for leasing by 
BLM (Hotze 2010, p. 18). These leases are either producing or are non-
producing. However, we expect the majority of new wells will be drilled 
in areas with high oil and gas potential. In high and moderate 
potential areas in Wyoming, a single well can produce 4 to 30 times as 
much as a well in low potential areas (BLM 2008b, p. A20:6). Most wells 
will be drilled in areas of high potential oil and gas resources 
(Copeland et al. 2009). Only 415,649 ha (1,027,057 ac), or 4.2 percent 
of the species' predicted range in Wyoming, occurs in high potential 
oil and gas resource in areas as defined by Seglund et al. (2006, p. 
39). Low and medium potential oil and gas resources overlap 73 percent 
of the gross range of white-tailed prairie dog (Seglund et al. 2006, p. 
39). Twenty-three percent of the gross range has no oil or gas 
resources. Given the existing development, we consider the area in 
southern Wyoming between Rawlins and Rock Springs to be a high 
potential area (Hotze 2010, p. 11).
    Oil and gas development and reserves occur throughout the gross 
range in Wyoming. We do not know the exact locations of future energy 
development facilities with respect to locations of white-tailed 
prairie dog colonies. Oil and gas development will likely impact white-
tailed prairie dogs, causing individual mortalities and habitat loss 
and fragmentation. However, as previously discussed, only a small 
portion (4.2 percent) of the species' gross range overlaps areas of 
high potential energy reserves. Energy development is most likely to be 
concentrated in areas of high potential reserves, so impacts to the 
white-tailed prairie dog will not occur at high levels across the 
species' entire gross range in Wyoming. Based on the available 
information, we do not believe oil and gas development in Wyoming is a 
threat to the species now or in the foreseeable future.

[[Page 30347]]

Summary of Oil and Gas Development

    Table 2 (below) gives a summary of the percentage of BLM-leased 
area for oil and gas in gross, predicted, and mapped occupied range, by 
State. Generally, the area attributed to producing leases makes up a 
small portion of the species' range, although up to 28 percent of the 
species' gross range has been leased for potential development.

 TABLE 2. Percentage of leased area for oil and gas in gross, predicted,
       and mapped occupied range of the white-tailed prairie dog.
  (Totals include a small amount of land authorized for leasing but not
  yet leased; and therefore not included in the other two categories.)
------------------------------------------------------------------------
                                   Percent    Percent Non-      Total
             State                Producing     Producing      Percent
                                   Leases        Leases        Leased*
------------------------------------------------------------------------
Colorado (Gross)                          9            20            30
------------------------------------------------------------------------
        Northwest IPA                     7            34            41
         (Predicted)
------------------------------------------------------------------------
        North IPA (Predicted)             2            22            25
------------------------------------------------------------------------
        Grand Valley/                     3            11            14
         Uncompahgre IPA
         (Predicted)
------------------------------------------------------------------------
        Total, Predicted range            5            25            30
------------------------------------------------------------------------
Utah (Gross)                             10            19            31
------------------------------------------------------------------------
        Uintah Basin (mapped             17            32            51
         occupied)
------------------------------------------------------------------------
        Carbon and Emery                  4            48            52
         Counties (mapped
         occupied)
------------------------------------------------------------------------
Wyoming (Gross)                           6            21            27
------------------------------------------------------------------------
Total (Gross)                             7            20            28
------------------------------------------------------------------------

    Oil and gas development is a major cause of development in the 
gross range of the species and is likely to continue into the 
foreseeable future at similar rates of development. Twenty-eight 
percent of the species' gross range is authorized for leasing. Leasing 
does not guarantee development, and therefore we consider the area 
leased Federally to be an estimate of the rangewide development, 
including non-Federal estate. A minimum of 13,000 additional wells will 
be authorized in the foreseeable future. However, energy development 
will not occur uniformly across the landscape. Most development will 
occur in areas of high resource potential. Development is also mediated 
by variations in well density and spacing. There are localized regions 
across the white-tailed prairie dog's gross range where development is 
most prevalent, including the Uinta Basin in Utah, the Northwest IPA in 
northwestern Colorado, and the southwestern region of Wyoming. The 
impacts to white-tailed prairie dogs would thus be greater in these 
locations than in other parts of the species' gross range.
    In areas where energy development overlaps occupied white-tailed 
prairie dog habitats, the resulting habitat loss and fragmentation 
likely has negative effects on individuals and populations, including 
mortality, noise disturbance, and habitat loss and fragmentation. 
Presumably, there is a threshold level wherein habitat loss and 
fragmentation may threaten the white-tailed prairie dog, at least in 
localized regions. However, our available information indicates energy 
development does not currently significantly threaten the species; for 
example, large prairie dog complexes continue to persist in areas of 
high energy development (see Colorado and Utah, above). Based on the 
information available to us, we have determined that oil and gas 
development does not significantly threaten the white-tailed prairie 
dog now or in the foreseeable future.
Development of Oil Shale, Tar Sands, and Other Minerals
    Extraction of oil shale and tar sands results in the removal of 
wide swaths of habitat. Oil shale and tar sands development results in 
a loss of habitat of the entire lease, although only portions of the 
lease would be impacted at a given time. Impact footprints for oil 
shale leases for strip mines are approximately 2,331 ha (5,760 ac) in 
size (BLM 2008c, p. 4:4), and each surface retort mine (an underground 
mine with processing of the material above ground) is approximately 668 
ha (1,650 ac) (BLM 2008c, p. 4:8). When an area is processed, the 
impact footprint shifts to another portion of the lease, and mined 
areas are reclaimed. The success of reclamation varies dependent on 
site conditions (BLM 2008c, p. 4:71). Oil shale and tar sand 
development activities can result in long- term or permanent habitat 
loss and fragmentation of white-tailed prairie dog habitats (BLM 2008c, 
p. 4:109) depending on the quality and success of habitat reclamation.
    Oil shale and tar sands resources occur across 8 percent of the 
gross range of the species (Hotze, 2010, p. 34). Approximately 
1,228,100 ha (3,034,696 ac) of potentially productive land for oil 
shale and tar sands occurs in Wyoming and Utah (BLM 2008c, p. 2:113), 
and the BLM made available 660,215 ha (1,631,424 ac) of Federal land 
for leasing in this area (BLM 2008c, p. ES:7). A very small portion of 
the white-tailed prairie dog's gross range is identified for leasing in 
Colorado (Seglund and Schnurr 2009, p. 121).
    Oil shale and tar sands development has failed to materialize due 
largely to technological problems and unfavorable economics. 
Significant economic questions remain regarding the development of the 
Green River formation oil shale and tar sands resources (Bartis et al. 
2005, pp. 15, 53; BLM 2006, pp. 7, 15-19, 31, 34-36). The cost 
associated with an essentially new industry using new and innovative 
technologies is likely to be great.

[[Page 30348]]

Economic success of oil shale- and tar sands-derived petroleum will 
depend on continuing high and stable petroleum prices. Due to past 
fluctuation of petroleum prices, private industry has exhibited a 
reluctance to proceed with research, development, and subsequent 
commercial production of oil shale. This situation will likely continue 
unless the petroleum industry is convinced that petroleum prices will 
remain high well into the future (Bartis et al. 2005, pp. 59-61; Bunger 
et al. 2004, pp. 7-9).
    Oil shale and tar sands extraction and development remains a 
speculative industry. At this time, we believe it is unlikely that the 
BLM will begin leasing the identified properties for development within 
the foreseeable future, which we define as approximately 10-15 years. 
In addition, while oil shale and tar sands resources overlap 8 percent 
of the species' gross range, actual oil shale and tar sands development 
facilities overlap with only a small portion (less than 0.1 percent) of 
the species' gross range. We do not believe development of oil shale 
and tar sands is a significant threat to the species now or in the 
foreseeable future.
Mineral Development
    Coal, uranium, sand, and gravel mining can result in the removal of 
habitat (BLM 2004, p. 4:12). These activities have the potential to 
result in long-term or permanent habitat loss and fragmentation, 
depending on the quality and success of habitat reclamation. These 
activities are not common land uses on BLM holdings in the gross range 
of the species. The BLM solid mineral leases total 108,170 ha (445,209 
ac), less than 1 percent of the species' gross range (Hotze 2010, p. 
30). The BLM coal leases total 88,167 ha (217,866 ac), also less than 1 
percent of the species' gross range (Hotze 2010, p. 32). Available 
evidence does not suggest solid mineral leases are more common on 
private lands. Available information does not suggest they will become 
more widespread within the species' gross range in the future. Given 
the small percentage of the gross range impacted by these activities, 
we do not believe mineral development is a significant threat to the 
species now or in the foreseeable future.
Renewable Energy Development--Wind and Solar
    The BLM has accessed areas of renewable resource potential with the 
objective of allowing the industries to focus development in the areas 
of highest potential (BLM and DOE 2003, p. 2). The majority of the 
species' gross range (Federal and non-Federal lands) has a low (~ 5kWh/
m2/day) amount of direct solar resources (BLM and DOE 2003, p. A2). 
Currently, less than 1 percent of the species' range has been leased by 
BLM for development of solar resources (BLM 2009, unpublished data). We 
are unaware of solar developments on private land within the gross 
range of the species. The majority of the land containing the species' 
range is federally owned, and therefore we consider potential solar 
developments on non-Federal land to be insufficient to threaten the 
species. Given the limited solar resources and lack of development to 
date in the species' range, we do not consider solar energy to be a 
significant threat to the species now or in the foreseeable future.
    Wind energy could impact the species by creating habitat loss, 
disturbance, or fragmentation; increasing the amount of invasive 
vegetation; increasing direct mortality; and increasing disturbance 
from noise and human presence (BLM 2005b, p. 5:42). Wind power has 
experienced a rate of expansion greater than any other renewable energy 
resource, and continued increases are predicted through 2030 (EIA 2009, 
pp. 47, 74). Depending on costs, wind power production could increase 
nationwide by as much as 38 percent by 2030 (EIA 2009, p. 74).
    The BLM manages more land areas of high wind resource potential 
than any other land management agency. In 2005, the BLM completed the 
Wind Energy Final Programmatic Environmental Impact Statement (EIS) 
that provides an overarching guidance for wind project development on 
BLM-administered lands (BLM 2005b, entire). Best management practices 
are prescribed to minimize impacts of all phases of construction and 
operation of a wind production facility. We do not have information on 
how or where the EIS guidance was applied since 2005 and, therefore, 
cannot evaluate its effectiveness.
    Wind energy developments leased by the BLM total 823,358 ha 
(2,034,562 ac), or approximately 4 percent of the species' gross range 
(Hotze 2010, p. 28). Only 5 to 10 percent of a development will have 
long-term surface disturbances (i.e., roads, foundations, substation, 
fencing) (BLM 2005b, p. 5:2).
    To evaluate the potential of future wind energy developments to 
impact the species, we examined the potential locations for 
development. Within the species' gross range in Colorado and Utah, only 
poor and marginal wind power resources exist (NREL 2003, entire; NREL 
2004, entire). In Wyoming, there are pockets of good, excellent, and 
outstanding wind power within the species' gross range in Fremont, 
Natrona, and Carbon Counties (NREL 2002, entire). The majority (more 
than 75 percent) of these counties are federally owned land. However, 
better wind power resources (rated as outstanding and superb, based on 
wind speeds) are available east of the species' gross range (NREL 2002, 
entire). We expect areas with the best wind resources will be developed 
first and receive more total development.
    We are unable to quantify the wind development scenario for private 
lands in the species' gross range. No central organization currently 
tracks wind development on private lands. Given the small amount of 
private land that coincides with an economically developable wind 
resource, we assume a maximum development of less than 10 percent of 
the species' gross range in Wyoming.
    The BLM maximum potential development scenario for wind energy in 
the entire State of Wyoming is an estimated total of 3,197,937 ha 
(7,902,000 ac) of potentially developable lands, but a much smaller 
amount is likely to be developed on BLM-administered lands (1,497 ha 
(3,700 ac)) (BLM 2005b, p. 5:2). The BLM estimates that only 5 to 10 
percent of BLM area, or 150 ha (370 ac) of lands, will have long-term 
surface disturbance (BLM 2005b, p. 5:2). We expect that much of the 
economically developable land exists outside the species' gross range, 
and given the small size of the total area on Federal lands likely to 
be developed in Wyoming (1,497 ha (3,700 ac)), and that the majority of 
the species' range occurs on Federal lands, we do not expect wind 
energy development to have a significant impact on the species.
    Because only small portions of the species' gross range are 
currently impacted by wind development and expected to be impacted in 
the future, we do not believe wind energy development represents a 
significant threat to the species. Given that projected development is 
small in regard to the size of the species' gross range, and that the 
majority of development will take place where better resources exist, 
we expect the overall impact of wind development on the white-tailed 
prairie dog to be low.
Urbanization
    Conversion of land for urban development results in a permanent 
loss of habitat and fragmentation for many species, including the 
white-tailed prairie dog. Increases in major population centers result 
in increased infrastructure, such as roads and

[[Page 30349]]

transmission lines. These infrastructure features may impact habitats 
beyond the immediate urban area. Increased urbanization can introduce 
domestic animals, such as dogs and cats, that may prey on some prairie 
dogs (Magle and Crooks 2009, p. 198). Human population growth may 
result in an increased use of surrounding public lands for recreation 
(Seglund and Schnurr 2009, p. 54).
    The effects of urban fragmentation on the white-tailed prairie dog 
have not been studied. Some information exists for the black-tailed 
prairie dog. Weights and sex ratios of black-tailed prairie dogs in 
urban environments were within normal ranges for the species (Magle 
2008, p. 116). However, black-tailed prairie dogs were more likely to 
occur on larger, contiguous habitats within the urban environments 
rather than smaller, highly fragmented parcels (Magle and Crooks 2009, 
p. 197). Collapses of existing colonies were observed within highly 
fragmented urban environments (Magle and Crooks 2009, pp. 197, 199). 
This information suggests that some prairie dogs can survive in 
fragmented habitat, but population loss increases with degree of 
fragmentation and amount of time since fragmentation occurred (Magle 
and Crooks 2009, p. 200).
    The rate of urbanization within the Rocky Mountain region is below 
the national average (White et al. 2009, pp. 41-42). As of 2004, 
urbanization affected 0.2 percent of the white-tailed prairie dog's 
gross range (Seglund et al. 2006, p. 45). Much of the existing and 
future predicted urbanization is localized to specific population 
centers, as further described below.

Colorado

    Twenty-eight percent of the overall white-tailed prairie dog's 
predicted range is expected to be impacted by high density urban 
development (i.e., less than 16 ha (40 ac) per housing unit), 5 percent 
by moderate density urban development (16 to 32 ha (40 to 80 ac) per 
housing unit), and 8 percent by low density urban development (greater 
than 32 ha (80 ac) per housing unit) by 2020 in Colorado (Seglund and 
Schnurr 2009, p. 171). Public land comprises 59 percent of the species' 
predicted range in Colorado and is not expected to be impacted by 
urbanization (Seglund and Schnurr 2009, p. 171). We expect that only 
moderate and high density urban development will negatively impact the 
species, because low density developments still provide large expanses 
of area for colonies to exist and allow for connectivity between 
colonies.
    The majority of urban development is predicted to occur in the 
Grand Valley-Uncompahgre IPA (Seglund and Schnurr 2009, pp. 52, 54). 
Urbanization has already fragmented white-tailed prairie dog habitats 
in this IPA (Seglund and Schnurr 2009, p. 54). By 2020, 37 percent of 
the IPA is expected to be impacted by high or moderate density urban 
development (Seglund and Schnurr 2009, p. 174). However, urbanization 
will be localized largely to the Grand Junction and Montrose urban 
areas. High or moderate density urban development will occur across 
much less of the North IPA (0.9 percent) and Northwest IPA (0.4 
percent) (Seglund and Schnurr 2009, p. 174).
    Urbanization has the potential to impact the species in Colorado, 
particularly in portions of the Grand Valley/Uncompahgre IPA. However, 
as noted above, high-density urbanization will be localized primarily 
to the human population centers of Grand Junction and Montrose. Because 
of its localized impact and the availability of large acreages of 
Federal, non-urbanized lands in the species' predicted range, we do not 
consider urbanization to be a significant threat to the species in 
Colorado now or in the foreseeable future.

Montana

    In Montana, 49 percent of the species' predicted range is privately 
owned (Table 1, above). Private land uses include grazing, agriculture, 
and housing; a metropolitan area is located in nearby Carbon County. At 
one time, 31 distinct white-tailed prairie dog colonies occurred in 
Montana. Urbanization resulted in the loss of 3 colonies to road 
construction and development (Begley 2010b, pers. comm.). An additional 
20 colonies were lost to impacts associated with mining, agriculture, 
or other unknown causes not directly attributable to urban development 
(Begley 2010b, pers. comm.).
    Of the eight remaining colonies in Montana, four occur on privately 
owned land (Begley 2010b, pers. comm.). Three of these colonies are in 
areas that support livestock grazing (Begley 2010b, pers. comm.). We 
are unaware of any plans to develop these properties in the foreseeable 
future. The remaining four colonies occur on Federal lands and are thus 
not threatened by urbanization. Therefore, we do not consider 
urbanization in Montana to significantly threaten the species now or in 
the foreseeable future.

Utah

    Urban development is expected to expand by 188,600 ha (466,041 ac) 
across the State of Utah by the year 2030 (White et al. 2009, p. 44). 
However, development is localized to metropolitan areas along the 
Wasatch front in Weber, Morgan, Summit, Davis, Salt Lake, Toole, Utah, 
and Juab Counties (U.S. Department of Agriculture (USDA) 2008, p. 2; 
U.S. Census Bureau (USCB) 2005a, p. 1). These areas do not overlap the 
species' gross range.
    The majority of white-tailed prairie dogs in Utah occur in the 
Uinta basin (Lupis et al. 2007, p. 17). The potential for future urban 
development in the Uinta Basin is associated largely with the city of 
Vernal (USCB 2005a, p. 1). Vernal is a support and staging area for the 
oil and gas development (see Factor A. Oil and Gas Exploration and 
Development) of the Uinta basin; increased urbanized development is 
primarily the result of increased oil and gas expansion. However, much 
of the required urban infrastructure is already in place, and the 
majority of gross range in Utah is managed by Federal agencies (Table 
1, above). The gross range and mapped occupied habitat of the white-
tailed prairie dog in the Uinta basin does not overlap the developing 
areas associated with the city of Vernal; thus we expect that most of 
the predicted development through 2030 will occur outside of the 
species' gross range.
    We evaluated the likely centers for urbanization in Utah through 
2030 and compared these to the gross range and mapped occupied habitat 
of the white-tailed prairie dog. Based on our evaluation, we do not 
consider urbanization to be a significant threat to the species in Utah 
now or in the foreseeable future.

Wyoming

    Wyoming has the largest amount of white-tailed prairie dog habitat 
and the smallest amount of predicted development. Over 46 percent of 
the species' gross range occurs in counties with no urban development: 
Park, Big Horn, Washakie, Hot Springs, Sublette, and Carbon Counties 
(USCB 2005b, p. 1). Only localized, small portions of the remaining 
counties will be impacted in the metropolitan area of Casper and the 
micropolitan areas of Riverton, Evanston, Rock Springs, and Laramie 
(USCB 2005b, p. 1). Given these factors, we do not believe urbanization 
is a significant threat to the species in this State now or in the 
foreseeable future.
    In summary, habitat loss and fragmentation due to urbanization may

[[Page 30350]]

impact the white-tailed prairie dog, but only in localized areas. There 
is no indication that there will be significant increases in 
urbanization across the species' gross range in the future. Therefore, 
we do not believe urbanization to be a threat to the species now or in 
the foreseeable future.
Agricultural Land Conversion
    Agricultural land conversion is the change in land use from any use 
to an agricultural use, including crops and pastures. Agricultural 
crops can benefit prairie dogs by providing highly nutritious forage 
(Crocker-Bedford 1976, pp. 73-74; Seglund and Schnurr 2009, p. 95). 
However, these colonies also are subject to additional mortality 
factors including higher lethal control efforts (see Factor B. Shooting 
and Factor E. Poisoning) to protect crops (Knowles 2002, p. 12), 
increased habitat fragmentation from fences and roads, and increased 
urban predators (Seglund and Schnurr 2009, p. 95).
    The impact of past agricultural conversion is difficult to 
determine given how little we know about the historical range of white-
tailed prairie dogs. Historical population declines occurred for all 
prairie dog species, and range contractions were documented for white-
tailed prairie dogs in localized areas in Colorado and Montana (Knowles 
2002, p. 12). However, we do not know if these losses were the result 
of agricultural conversion or other factors; it is likely that 
historical population losses were the result of a combination of 
impacts across the range of the species. Agricultural land conversion 
probably displaced some white-tailed prairie dogs in areas of Colorado 
and the Big Horn Basin in Wyoming (Knowles 2002, p. 12).
    Today, agriculture occurs across 3.7 percent of the gross range of 
the white-tailed prairie dog (Seglund et al. 2006, p. 50). Many of the 
areas currently inhabited by white-tailed prairie dogs are arid and 
semi-arid with short growing seasons (Seglund et al. 2006 pp. 4-5) and 
therefore have limited potential for crops. In Colorado, the counties 
containing white-tailed prairie dogs saw a decrease in the amount of 
agricultural land by an average of 37 percent between 1954 and 2002 
(calculated from data in Seglund and Schnurr 2009, p. 96). Farm land 
(e.g., crops, pasture, grazing (not including Federal grazing permits), 
USDA 2009, p. B:14) acreages have continued to decline across all 
States and counties that occur within the gross range of the white-
tailed prairie dog (see Table 3, below). There is not a direct 
correlation between the decline in farm lands and increases in other 
land uses, although it is likely that the farmland has been re-
converted to other rural uses, such as grazing, or has become urbanized 
(see Factor A. Urbanization).

  TABLE 3. Percentage Decrease of Farm Land, Statewide and in Counties
 partly or wholly contained within the Range of the White Tailed Prairie
Dog, Between 2002 and 2007 (USDA 2009, pp. CO 316, UT 249, WY 268, 316).
------------------------------------------------------------------------
                                                               Counties
                                                                Within
                                                                White-
                     State                       Statewide      tailed
                                                             Prairie Dog
                                                                Range
------------------------------------------------------------------------
Wyoming                                                12.1         14.0
------------------------------------------------------------------------
Colorado                                                7.6          9.5
------------------------------------------------------------------------
Utah                                                    2.3         13.1
------------------------------------------------------------------------
Average                                                 7.3         12.2
------------------------------------------------------------------------

    In summary, agricultural land conversion was likely a major 
historical impact on the species. However, many of the areas currently 
inhabited are not suitable for crop lands, and appear to be supporting 
sufficient populations of the species. The effects of land conversion 
on the species are mixed, and currently very limited land is being 
converted to agricultural uses. Therefore, we do not consider 
agricultural land conversion to be a significant threat to the species 
now or in the foreseeable future.
Grazing
    Native herbivores, such as pronghorn antelope (Antilocarpo 
americana), mule deer (Odocoileus hemionus), and bison (Bison bison), 
occurred in the sagebrush-steppe region prior to European settlement of 
western States (Osborne 1953, p. 267; Miller et al. 1994, p. 111), and 
prairie dogs co-evolved with these grazers. Domestic livestock grazing 
in the intermountain west began with the arrival of European settlers 
in the 1800s. The numbers of livestock were unregulated, and peaked in 
the early 1900s (Oliphant 1968, p. vii; Young et al. 1976, pp. 194-195, 
Carpenter 1981, p. 106; Donahue 1999, p. 15; Seglund et al. 2006, pp. 
49, 51), with an estimated 19.6 million cattle and 25 million sheep in 
the West (BLM, 2009, pp. 1-2).
    Excessive grazing by domestic livestock during the late 1800s and 
early 1900s, along with severe drought, significantly impacted 
sagebrush ecosystems (Knick et al. 2003, p. 616). Livestock grazing 
continues to be the most widespread type of land use across the 
sagebrush biome (Knick et al. 2003, p. 616; Connelly et al. 2004, pp. 
7-29; Knick et al., in press, p. 27). However, the intensity of grazing 
on all Federal lands has declined since the early 1900s (Laycock et al. 
1996, p. 3).
    Livestock grazing can affect ecosystem functions and structures, 
including a general decrease in grass and shrub cover, total plant 
biomass, and rodent species diversity and richness (Fleischner 1994, 
pp. 633-635; Jones 2000, pp. 160-161). Fencing and roads associated 
with grazing may cause habitat fragmentation and may directly or 
indirectly cause increased mortality of prairie dogs by increasing 
prairie dog-vehicle collisions, creating perch sites for raptors, and 
providing access corridors for predators (Call and Maser 1985, p. 3; 
Connelly et al. 2000, p. 974; Connelly et al. 2004, pp. 1-2).
    ``Overgrazing'' refers to continued heavy grazing beyond the 
recovery capacity of the forage plants (Vallentine 1990, p. 329). 
Overgrazing causes the palatable and preferred herbaceous vegetation of 
prairie dogs to be preferentially removed, allowing shrubs and 
unpalatable plants to flourish. Overgrazing can facilitate the 
establishment of invasive species such as cheatgrass (Bromus tectorum) 
(Masters and Sheley 2001, p. 503) (see below for more information). The 
intensity, duration, and distribution of livestock grazing are more 
influential on rangeland condition than livestock density (Aldridge et 
al. 2008, p. 990). Grazing impacts to rangeland are determined by the 
type of animal, stocking rate, duration of grazing, season of use, and 
current habitat conditions (Vallentine 1990, entire).
    Impacts of livestock grazing on white-tailed prairie dogs are not 
known largely because of our lack of historical species distribution 
information and the lack of ungrazed habitats as a baseline (Seglund et 
al. 2006, p. 49). Overgrazing may impact prairie dogs by degrading the 
quality and quantity of forage; decreasing forage availability during 
important breeding, rearing, and pre-hibernation periods; and 
decreasing white-tailed prairie dog reproductive success and over-
wintering survival (Seglund et al. 2006, p. 49). However, the potential 
for impacts is likely to be site-specific. For example, removing 
livestock from shrub-steppe habitat can result in either an increase of 
species richness (Anderson and Inouye 2001, pp. 538, 544-545, 549-550), 
or a decrease in species richness (Manier and Hobbs 2007, p. 743), 
depending on site variables.

[[Page 30351]]

    Grazing effects to other prairie dog species are known to some 
degree. Livestock grazing can have positive effects on black-tailed 
prairie dog colonies because of grazing's effect of converting mid-
height and tall grasses to short grasses improves predator surveillance 
visibility (Uresk et al. 1981, p. 200; Cable and Timm 1987, p. 46). 
Overgrazing was shown to negatively affect Utah prairie dog growth 
rates, foraging ability, and survivorship (Cheng and Ritchie 2006, p. 
550). Utah prairie dog colony extinction rates increased as plant 
species richness declined due to overgrazing (Ritchie 1999, p. 12). 
Heavy grazing also can contribute to an increase in shrubs in Utah 
prairie dog habitat (Crocker-Bedford 1976, p. 88). However, over time, 
Utah prairie dogs prefer areas with moderate grazing intensities over 
ungrazed areas, because sufficient forage remained available in the 
grazed plots (Cheng and Ritchie 2006, p. 554); cattle cannot eat plants 
below 2 centimeters (0.879 in), limiting the impacts of moderate 
grazing on prairie dogs. Results from the Utah prairie dog studies are 
most applicable to white-tailed prairie dogs due to similarities in 
habitat preferences. Both species use arid shrub-steppe habitats, and 
white-tailed prairie dogs can utilize shrub cover for hiding (Gadd 
2000, pp. 24-26). Therefore, we assume that white-tailed prairie dogs 
react to grazing in a similar manner to Utah prairie dogs. However, 
reactions to overgrazing may not be as extreme in the white-tailed 
species due to their higher shrub tolerance.
    We do not have information regarding site-specific range conditions 
on Federal or non-Federal allotments that overlap white-tailed prairie 
dog habitats. Range condition data is not collected in a manner that is 
biologically meaningful for small mammals. White-tailed prairie dogs, 
being a diet generalist living in arid environments, can persist with 
limited forage. It is unknown how far range condition must deteriorate 
before a habitat becomes incapable of supporting a colony. Therefore, 
we do not know how much of the habitat is overgrazed versus moderately 
grazed. It is likely that overgrazing impacts white-tailed prairie dog 
colonies in localized portions across the species' range. However, the 
available literature indicates that prairie dogs can coexist with some 
level of grazing, and in some cases, benefit from grazing. White-tailed 
prairie dogs have persisted during higher historical grazing pressures 
and livestock stocking rates have declined substantially. Therefore, we 
do not consider grazing to be a significant threat to the species now 
or in the foreseeable future.
Fire Occurrence and Suppression
    The shrub-steppe habitat occupied by the white-tailed prairie dog 
evolved with infrequent fire frequency intervals of 100 to 450 years 
depending on the dominant species of sagebrush (Baker 2006, pp. 180-
181). Fire suppression activities also were infrequent (Baker 2006, p. 
182) and probably had little effect on sagebrush landscapes (Baker in 
press, p. 22).
    Fire ecology of sagebrush habitats has changed since European 
settlement of the West. In general, fire frequencies have increased in 
lower elevation sagebrush habitats due to (and resulting in further) 
invasion of nonnative annual grasses, such as cheatgrass (Baker 2006, 
p. 178; Crawford et al. 2004, p. 8). Fire frequencies also have 
increased due in part to human activities and presence (Miller et al. 
in press p. 38). Fire frequencies have declined in higher elevation 
sagebrush habitats, resulting in the expansion of shrubs and trees 
(Miller and Rose 1999, p. 557; Baker 2006, p. 178; Crawford et al. 
2004, p. 8). The number of fires and total area burned increased from 
1980-2007 in sage-grouse habitat (Miller et al. in press, p. 39); this 
overlaps much of the white-tailed prairie dog's gross range in Wyoming 
and Colorado. However, the habitat mosaics and effects to wildlife 
resulting from fires are not well understood and vary across the 
landscape (Baker 2006, pp. 178, 183).
    We do not have information specific to the effects of fire or fire 
suppression on white-tailed prairie dogs. White-tailed prairie dogs are 
adapted to a shrub-steppe grass mosaic. They use shrubs as forage and 
cover from predators (Tileston and Lechleitner 1966, pp. 31, 302; 
Hoogland 1981, pp. 266-268; Gadd 2000, pp. 24-26). They feed on forbs 
and grasses, and these can be increased by fire in shrubland habitat 
(Pyle and Crawford 1996, p. 323; Davies et al. 2007, p. 518).
    We anticipate that the impacts of fire to white-tailed prairie dogs 
will vary locally across the species' gross range. In some places where 
fire has occurred, shrub or pinyon-juniper invasions are likely to 
occur and may reduce available sagebrush communities for the species 
(Miller and Rose 1999, p. 557). In other cases, cheatgrass may become 
the dominant plant species (Baker 2006, p. 178; Crawford et al., p. 8), 
reducing preferred forage quantity and quality for the white-tailed 
prairie dog. However, the white-tailed prairie dog is able to use the 
mosaic of habitats created by fire and fire suppression activities, and 
thus we do not believe that fire occurrence or suppression is a 
significant threat to the white-tailed prairie dog now or in the 
foreseeable future.
Invasive Plant Species
    Invasive plant species are promoted by intense levels of 
disturbance to the environment (Masters and Shelley 2001, p. 504), such 
as oil and gas development, agriculture, and urbanization. Invasive 
plant species alter ecological processes by displacing native species, 
increasing the vulnerability of communities to more invaders, and 
reducing wildlife habitat quality (Masters and Sheley 2001, p. 503). 
They can be particularly damaging in areas of low moisture, including 
shrub-steppe habitats, because they reduce water infiltration of the 
soil and possess deeper roots than native species, allowing them to use 
more water and reduce nutrient availability over time (DiTomaso 2000, 
p. 257). The proliferation of exotic annual weeds over native perennial 
grasses and forbs may impact the ability of white-tailed prairie dogs 
to meet their dietary needs, especially during drought years. Utah 
prairie dog colony extinction rates were found to increase as the 
number of locally occurring plant species declined (Ritchie 1999, p. 
12). Cheatgrass in particular is widely distributed across the gross 
range of the white-tailed prairie dog. Cheatgrass creates an altered 
fire regime, increasing the amount of fire and reducing native grasses 
and shrubs (Masters and Sheley 2001, p. 503). Juniper species have 
invaded sagebrush habitat beginning with European settlement (Miller 
and Rose 1999, pp. 551, 555), and may result in decreased habitat if 
forestation progresses.
    The main effect of invasive species is the decrease in habitat 
quality and forage. Some habitat may be lost due to pine-juniper 
invasion. It is likely that invasive species will have localized 
impacts to individual white-tailed prairie dog habitat. Presumably, a 
certain amount of invasive species is tolerable. Despite localized 
impacts, no data indicate that invasive species are threatening the 
species on a rangewide scale. At this point, the available information 
does not indicate that invasive species, although present within the 
gross range, are a significant threat to the white-tailed prairie dog 
now or in the foreseeable future.
Climate Change
    Global surface temperatures rose (with regional variations) during 
the past 157 years, with the largest increases occurring since the 
1970s (Trenberth et

[[Page 30352]]

al. 2007, p. 252). Globally, average surface temperatures rose by 0.074 
degrees Celsius ([deg]C) plus or minus 0.018 [deg]C (0.13 degrees 
Fahrenheit ([deg]F) plus or minus 0.03 [deg]F) per decade during the 
past century (1906 through 2005) and by 0.177 [deg]C plus or minus 
0.052 [deg]C (0.32 [deg]F plus or minus 0.09 [deg]F) per decade during 
the past quarter-century (1981 through 2005) (Trenberth et al. 2007, p. 
253).
    Similar surface temperature increases occurred across the gross 
range of the white-tailed prairie dog. The Southwest region, including 
the Colorado and Utah portion of the species' gross range, observed a 
0.83 [deg]C (1.5 [deg]F) increase in average temperatures when compared 
to a 1960 to 1979 baseline (Karl et al. 2009, p. 129). The Great Plains 
region (including the Wyoming and Montana portion of the gross range) 
experienced a 0.83 [deg]C (1.5 [deg]F) increase over average 
temperatures, compared to the same baseline (Karl et al. 2009, p. 123). 
Drought conditions across the species' gross range were moderate to 
extreme (Marshall et al. 2008, p. 274).
    The timeframe over which the best available scientific information 
allows us to reliably assess the effects of climate change is an 
important consideration. Until about 2050, greenhouse gas emissions 
scenarios (reviewed in the Intergovernmental Panel on Climate Change 
Special Report on Emission Scenarios in 2000, as cited in Ray et al. 
2009, p. 8), which are an essential component of any climate change 
assessment, result in a similar range of projections of global and 
regional climate change (Ray et al. 2009, p. 8). Temperature increases 
over the next 30 to 50 years are relatively insensitive to the 
emissions scenarios used to model the projected change. Some warming, 
as projected in the greenhouse gas emissions scenarios, is anticipated 
as a result of greenhouse gases already in the atmosphere that will 
influence future climate, more so for mid-century versus late century 
(Meehl et al. 2007, p. 749; Mote and Salathe 2009, p. 30). The range in 
the spread of the models is due both to details in the formulation 
(which includes emission scenarios) of each individual model, and 
natural variability in climate. Because increases of greenhouse gas 
emissions have lag effects on climate, and because projections of 
greenhouse gas emissions can be interpreted with greater confidence 
until approximately mid-century, model projections for the next 30 to 
50 years (centered on 2050) have greater credibility than results 
projected further into future. On the basis of available information, 
we have determined that predicted climate changes for 2025 and 2050 are 
more reliable than projections for the second half (up until 2100) of 
the 21st century and as such, we consider 2050 to represent the 
foreseeable future.
    One scenario predicts an average increase in annual temperature in 
western North America (covering the entire gross range of the species) 
of between 1.1 to 3.4 [deg]C (2 to 4 [deg]F) by 2050, compared to a 
1961 to 1979 baseline in the western United States (Smith et al. 2000, 
p. 29). Other predictions range from an annual mean warming of about 
1.4 to 3 [deg]C (2.5 to 5.5 [deg]F) by 2050 as part of a continent-wide 
pattern of warming (Ray et al. 2009 p. 15). The projections show 
summers warming more (1.7 to 3.9 [deg]C (3 to 7[deg]F)) than winters 
(1.1 to 2.7 [deg]C (2 to 5 [deg]F)) (Ray et al. 2009 p. 15)
    Climate change will affect precipitation. Generally, a reduction of 
depth, duration, and distribution of snowpack is expected (Solomon et 
al. 2007, pp. 770-772; Marshall et al. 2008, p. 276). Precipitation is 
predicted to decrease in the Southwest region (Karl et al. 2009, p. 
129), and increase in the Great Plains region (Karl et al. 2009, p. 
123). Climate change also will affect plague ecology (please see Factor 
C. Disease and Predation, below).
    Recent climatic changes, including increased temperatures and 
freeze-free periods, and changes in precipitation, are important 
driving forces on ecosystems and have affected a wide variety of 
organisms with diverse geographic distributions (Walther et al. 2002, 
pp. 391-392; Parmesan and Yohe 2003, p. 41). Many plant and animal 
species have advanced the timing of spring events (e.g., plant 
flowering or bird migration) to occur earlier in the year and 
experienced a shift in latitudinal and altitudinal range (i.e., 
movement to higher latitudes or higher altitude) (Walther et al. 2002, 
pp. 391-392).
    The white-tailed prairie dog and its habitat will likely be 
affected in some manner by climate change. Climate change could impact 
habitat quality, which may in turn affect prairie dog productivity. For 
example, higher quality habitats promote higher weaning success of 
adult and yearling female white-tailed prairie dogs (Cooke 1993, in 
Seglund et al. 2006, p. 7). We would expect higher quality habitats to 
occur in areas where rainfall is predicted to increase. Alternatively, 
increased drought in the southwestern portion of the gross range could 
reduce vegetation quality and quantity, resulting in lowered nutrition 
for the white-tailed prairie dog (Collier and Spillet 1975, p. 153; 
Seglund et al. 2006, p. 64). Drought may result in more time spent in 
burrows and less time spent foraging, as well as water-stress from lack 
of succulent forage (Collier and Spillet 1975, p. 153).
    Population fluctuations of white-tailed prairie dog colonies at the 
Coyote Basin Subcomplex, Kennedy Wash Subcomplex, and Snake John 
Subcomplex in Uintah County, Utah, were likely the result of drought 
(Maxfield 2009, pers. comm.). The 2002 drought resulted in a decrease 
in available forage for white-tailed prairie dogs at a time when 
populations had peaked. This resulted in little or no reproduction in 
2003, and a population crash in 2004 (Maxfield 2010, pers. comm.). 
Habitat conditions improved and the colonies rebounded to pre-drought 
population levels by 2008-2009 (Seglund et al. 2006, p. 101; Maxfield 
2010, pers. comm.), indicating a level of resiliency of this species to 
withstand at least short-term climatic variations.
    Life-history characteristics of the white-tailed prairie dog may be 
responsible for its resiliency and may provide protection from effects 
of climate change. The burrowing and hibernating behaviors of prairie 
dogs provide protection in times of low resource availability and 
unfavorable conditions, including those associated with climate change 
(Liow et al. 2009, pp. 264, 270). Overwinter survival and reproductive 
success is linked to habitat quality (Rayor 1985, p. 2839), so lack of 
adequate food resources during drought leads to a decrease in 
reproductive output as seen above. Individual animals also may adapt by 
becoming mostly inactive during times of drought (Liow et al. 2009, p. 
270).
    Shifts in the geographic ranges of wildlife have occurred as an 
effect of climate change (Walther et al. 2002, pp. 390-391), and may 
thus be anticipated for the white-tailed prairie dog. Due to the large 
gross range of the species (from the Southwest to the Great Plains, 
which are projected to have much different impacts from climate change, 
as discussed above), we expect the effects of climate change to vary 
throughout the species' gross range, both in nature of the impact and 
the timing of these effects. In addition, the species' gross range is 
contained within a region that already witnesses climatic variability 
as climate varies considerably between years (Smith et al. 2000, p. 
224). Therefore we expect the effects of climate change to vary 
temporally (year-to-year) as well. This variation in effects will 
buffer the cumulative effects of climate change on the species as a 
whole because only a

[[Page 30353]]

portion of the gross range will be impacted at a given time.
    Although the white-tailed prairie dog will likely be affected by 
climate change, it is not apparent that a net loss in occupied habitat 
will result. Variation in conditions across the gross range and a 
possible gross range shift could maintain sufficient habitat for the 
species. The species is adaptable to a wide array of climes, as 
evidenced by a geographic range that includes four States, as well as a 
wide elevational distribution (see Ecology and Life History, above). 
Unlike more vulnerable species in polar, coastal, and alpine 
ecosystems, habitat space exists to accommodate shifts in range. 
Therefore, we do not believe that climate change poses a threat to the 
species now or in the foreseeable future. The relationship between 
climate change and plague is discussed in more detail below (see Factor 
C. Disease or Predation).
Summary of Factor A
    Energy development, urbanization, agricultural conversion, grazing, 
fire suppression, introduction of invasive plant species, and climate 
change within the gross range of the white-tailed prairie dog have 
occurred and will continue to occur in the future. We do not expect oil 
shale, tar sands, coal, and other mineral extraction activities to 
impact a large portion of the species' gross range. Urbanization will 
have an effect on some local populations, particularly in Colorado, but 
is not considered a rangewide threat. Grazing is likely impacting some 
areas of habitat, but no evidence indicates it is a significant threat. 
A net loss of habitat is not expected to result from climate change. 
Oil and gas development has the most potential to impact the species 
due to its widespread distribution and magnitude, yet the intensity of 
these activities varies greatly across the range due to differences in 
well density and spacing. Robust colonies and complexes exist even in 
the most developed areas. The majority of the gross range has not been 
subject to the intensity of development witnessed around robust 
colonies of Coyote Basin and Wolf Creek. While further development will 
occur, we expect the majority to occur in areas with high potential for 
productivity. Therefore, we do not consider oil and gas to be a 
significant threat to the species. We have no indication that invasive 
plant species are a significant threat to the white-tailed prairie dog 
now or in the foreseeable future.
    We conclude that the best scientific and commercial information 
available indicates that the white-tailed prairie dog is not now, or in 
the foreseeable future, threatened by the present or threatened 
destruction, modification, or curtailment of its habitat or range to 
the extent that listing under the Act as an endangered or threatened 
species is warranted at this time.

Factor B. Overutilization for commercial, recreational, scientific, or 
educational purposes.

    White-tailed prairie dogs were historically subjected to 
recreational hunting and shooting as a form of pest management on ranch 
and agricultural land; these practices continue under State regulations 
(see Factor D. Inadequacy of Existing Regulatory Mechanisms).
    The effects of recreational shooting on white-tailed prairie dogs 
have not been examined. We do have limited information on how shooting 
affects black-tailed prairie dog populations. Black-tailed prairie dogs 
in colonies subject to hunting spent more time in alert behaviors and 
less time foraging, although this effect decreased a year after 
shooting (Pauli and Buskirk 2007, p. 1223). Recreational shooting 
reduced black-tailed prairie dog density at specific sites (Vosburgh 
and Irby 1998, pp. 366-367; Knowles 2002, p. 14) and may negatively 
affect reproductive rates (Pauli and Buskirk 2007, p. 1228). However, 
recovery of black-tailed prairie dog populations following shooting 
occurs (Knowles 1988, p. 54). No research has evaluated long-term 
impacts from recreational shooting, although population viability 
monitoring suggests it is unlikely to lead to extinctions of even small 
populations (Seglund and Schnurr 2009, p. 167).
    Life-history traits and species distribution are likely to mediate 
the effects of shooting on white-tailed prairie dogs. The majority of 
black-tailed prairie dogs do not reproduce until 2 years of age 
(Hoogland 2001, p. 920). White-tailed prairie dogs, as previously 
stated, reach maturity at 1 year of age. Thus, we believe that white-
tailed prairie dog populations may be able to recover from the effects 
of shooting more quickly than black-tailed prairie dogs.
    Human recreationists may prefer targeting black-tailed prairie dogs 
because they live in larger, denser, more identifiable colonies and 
their mounds are more conspicuous (Seglund et al. 2006. p. 55). White-
tailed prairie dogs are more dispersed on the landscape and use 
shrubland habitat for cover from predators. As a consequence, they may 
be more difficult to find and successfully shoot (Grenier 2009, pers. 
comm.), limiting the number of recreationists targeting white-tailed 
prairie dog colonies.
    Recreational hunting is permitted rangewide, but it is unlikely 
that all colonies are exposed to equal risk. Recreational hunting is 
concentrated on colonies with reasonably easy access (Gordon et al. 
2003, p. 12). Colonies at higher elevations or in remote areas may 
never receive hunting pressure due to the difficulty in gaining access. 
Colonies in close proximity to urban areas and agricultural fields 
likely receive the greatest shooting pressure (Gordon et al. 2003, p. 
12; Seglund et al. 2006, p. 33). Urban and agricultural land uses 
affect a small part of the species' gross range (see Factor A).
    The reproductive cycle of prairie dogs may influence impacts of 
recreational shooting. Lactating females spend the most time above 
ground, and lactation occurs during the months of April through July 
(Tileston and Lechleitner 1966, p. 301). During this time, adult male 
activity decreases. Recreational hunting in April, May, and June may 
have the greatest population level impacts because pregnant and 
lactating females and young of the year are the most vulnerable 
(Vosburgh and Irby 1998, p. 369; Keffer et al. 2000, p. 7). 
Recreational shooting could remove more offspring than adults or 
artificially skew the population sex ratio. Thus, seasonal restrictions 
may be important to reduce the effects of shooting at localized sites.
    Seasonal white-tailed prairie dog hunting regulations are 
implemented in Utah and Colorado. In Utah, shooting is not permitted on 
white-tailed prairie dog towns between April 1 and June 15 (Utah 
Division of Wildlife Resources (UDWR) 2007, p. 4). In Colorado, 
shooting is not permitted on public land between March 1 and June 15 
(Colorado Division of Wildlife (CDOW) 2009, p. 10). These closures may 
reduce impacts to the demographic structure and are expected to provide 
protection to white-tailed prairie dog populations (Seglund and Schnurr 
2009, p. 165).
    Recreational and pest removal shooting of white-tailed prairie dogs 
is allowed without a permit across much of the species' gross range; 
only Colorado requires a license. Because permits are not required, 
quantifying the number of prairie dogs killed by shooting is difficult. 
The only data available are from Colorado's Harvest Information Program 
(CDOW 2001-2005). In this program, a random survey of registered 
hunters was performed and an estimated take extrapolated from the 
survey results. This program does not differentiate between species of 
prairie dog, so estimates include Gunnison's,

[[Page 30354]]

black-tailed, and white-tailed prairie dogs.
    According to the data in Colorado's 2000-2005 Small Game Harvest 
Reports, prairie dogs are not a common target among hunters. Only 4.6 
to 7.4 percent of hunters reported shooting prairie dogs (CDOW 2001-
2005). In addition, as previously discussed, the majority of hunted 
prairie dogs are likely to be black-tailed and Gunnison's prairie dogs, 
not white-tailed prairie dogs. Therefore, we do not believe this 
represents high hunting pressure on white-tailed prairie dogs.
Summary of Factor B
    White-tailed prairie dogs, due to their distribution and life-
history characteristics, are likely less affected by shooting than 
other species of prairie dogs. Effects of recreational shooting may be 
high on specific, easily accessible, localized colonies. However we do 
not expect that these effects will occur equally across the species' 
gross range or significantly threaten the species as a whole.
    There are no other known threats due to commercial, scientific, or 
educational uses of this species. We conclude that the best scientific 
and commercial information available indicates that the white-tailed 
prairie dog is not now, or in the foreseeable future, significantly 
threatened by the overutilization for commercial, recreational, 
scientific, or educational purposes.

Factor C. Disease or predation.

Sylvatic Plague
    Sylvatic plague (plague) is an exotic disease foreign to the 
evolutionary history of North American prairie dogs. Plague was first 
observed in wild rodents in North America near San Francisco, 
California, in 1903 (Eskey and Haas 1940, p. 1), and was first 
confirmed in white-tailed prairie dogs in 1936 (Eskey and Haas 1940, p. 
14). It now occurs throughout the entire species' gross range (Biggins 
and Kosoy 2001, p. 906; Pauli et al. 2006, p. 3).
    Plague is caused by a bacterium (Yersinia pestis), which fleas 
acquire by biting infected animals and subsequently transmit via a bite 
to other animals (Gage and Kosoy 2005, pp. 516-517). The disease also 
can be transmitted through pneumonic (airborne) or septicemic (blood) 
pathways from infected to disease-free animals (Barnes 1993, p. 28; Ray 
and Collinge 2005, p. 203; Cully et al. 2006, p. 158; Rocke et al. 
2006, p. 243; Webb et al. 2006, p. 6236).
    Plague occurs in prairie dog colonies as enzootic and epizootic 
events. Enzootic plague is an infection maintained in the population 
over time and causes a low rate of mortality within the colony. Not all 
individuals are affected because the low density within a colony 
results in less contact between individuals and a reduced transmission 
rate. Epizootic plague occurs when the disease spreads from enzootic 
hosts to more susceptible animals, resulting in a rapidly spreading 
die-off cycle (Barnes 1993, p. 29; Biggins and Kosoy 2001, p. 909; 
Cully and Williams 2001, p. 900; Gage and Kosoy 2005, pp. 506-508). 
Large numbers of animals can die within a few days (Lechleitner et al. 
1962, pp. 190-192; Cully 1993, pp. 40-42).
    The factors that cause a change from an enzootic to epizootic cycle 
are still being researched, but may include host density, flea density, 
and climatic conditions (Cully 1989, p. 49; Parmenter et al. 1999, p. 
814; Cully and Williams 2001, pp. 899-903; Enscore et al. 2002, p. 186; 
Lomolino et al. 2003, pp. 118-119; Stapp et al. 2004, p. 237; Gage and 
Kosoy 2005, p. 509; Ray and Collinge 2005, p. 204; Stenseth et al. 
2006, p. 13110; Adjemian et al. 2007, p. 372; Snall et al. 2008, p. 
246). Plague cycles (e.g., epizootic, recovery, enzootic) may result in 
successive population peaks that are progressively lower than the 
previous peak and that with each new epizootic, the loss of colonies 
from plague will exceed the rate of establishment of new colonies 
(Knowles 2002, p. 13). However, this pattern of progressively lower 
peaks has not been consistently observed throughout significant 
portions of the species' gross range.
    White-tailed prairie dogs are extremely susceptible to plague 
(Williams 1986, p. 4). Individual colony population declines of 85 to 
96 percent were reported throughout the species' gross range following 
epizootic plague events (Anderson and Williams 1997, pp. 702, 729). 
Recovery of white-tailed prairie dog colonies post-plague has occurred 
within as little as 1 to 2 years (Anderson and Williams 1997, p. 728; 
Menkens and Anderson 1991, p. 330; Anderson and Williams 1997, p. 728; 
Seglund et al. 2006, p. 69), or can take greater than 10 years (see 
site discussions below, particularly Little Snake). Epizootic plague 
frequently recurs in colonies (Barnes 1993, p. 29; Cully 1993, p. 39).
    Plague likely persists in prairie dog colonies as an enzootic even 
when an epizootic outbreak subsides. In the absence of epizootic 
events, plague was found in fleas, plague antibodies were found in 
prairie dog and carnivore blood serum samples, and dead plague-positive 
prairie dogs were found (Biggins et al. in press, p. 7). More evidence 
of enzootic plague acting in populations of prairie dogs and of black-
footed ferrets is an increase in survivorship when treated with 
experimental vaccines and flea control, even in the absence of 
epizootic plague outbreaks (Matchett et al. 2009 in Biggins et al. in 
press, p. 7). Increased survival with these treatments compared with 
untreated areas is indicative that enzootic plague is frequently 
present and suppressing population levels in untreated areas.
    Possible reasons for maintenance of plague as an enzootic in the 
environment include survival of the bacterium in the soil, persistence 
of the bacterium in fleas, and the continued slow transmission of the 
bacterium within the prairie dog community (Gage and Kosoy 2006 in 
Biggins et al. in press, p. 2). Infected fleas exist in burrows for up 
to 13 months following a plague event (Fitzgerald 1993, p. 57).
    Impacts of long-term enzootic plague infection may include local 
extirpation of colonies, extreme fluctuations in densities and occupied 
habitat, and inbreeding (Seglund et al. 2006, p. 58). Enzootic plague 
also may alter ecological processes (Biggins 2003, p. 7), such as 
population dynamics and dispersal. For example, if plague results in 
higher mortality of adults than juveniles, the remaining juveniles 
would be less likely to disperse away from their native colonies; they 
would instead replace the adults in the native colony, resulting in a 
younger population (Biggins et al. in press, pp. 2, 7).
    We lack an understanding of how plague is impacting the white-
tailed prairie dog on a rangewide basis. Plague monitoring is not 
performed rangewide. To assess the effects of plague, we evaluated 
available population and trend data on colonies and complexes known or 
suspected to be affected by plague. Sharp declines in abundance are 
generally attributed to epizootic plague outbreaks in the absence of 
testing. No data was available before the 1980s; all available data 
were collected after introduction of plague, in what we consider to be 
a post-plague environment. Therefore, recovery is defined as a return 
to observed population highs and not a return to pre-plague (prior to 
1936 when it was first observed) abundance. We previously defined 
persistence as the long-term continuance of white-tailed prairie dog 
colonies, at a high enough level to exist in the long-term with minimal 
management assistance (i.e., dusting, the application of insecticides

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to control flea populations, to reduce the spread of plague), in a 
variety of locations across the species' gross range. We recognize that 
different methodologies were used at different times and in different 
locales to derive the various historical estimates we obtained for 
review. These estimates contribute to the best available information, 
and we consider them comparable for determining long-term population 
trends, while acknowledging potential error margins.
    Evaluating the data is difficult due to differences in survey 
methodologies. Information available for various colonies is 
alternately presented as surveys of active burrows, occupied habitat, 
population estimates, or prairie dog counts. For this reason, 
comparison between colonies is not appropriate, and we review each 
colony individually to derive a general understanding of plague 
effects. Available data for several colonies includes estimated prairie 
dog populations and prairie dog counts for different years; these 
figures are not directly comparable but still describe general trends.
    Much of the available data is for sites that were considered for 
black-footed ferret management areas, which often, but not always, 
represent the most robust of the known white-tailed prairie dog 
colonies. Data collected at many of these sites was intended to 
determine suitability for black-footed ferret reintroduction, and not 
specifically designed to measure prairie dog abundance. The following 
is a discussion of some examples of white-tailed prairie dog complexes 
that have been impacted by plague. Some have declined and maintain 
lower numbers (appear to still be in a period of decline), while other 
complexes have declined but either partially or fully recovered. We 
believe population numbers in colonies or portions of colonies will 
continue to fluctuate widely, but retain the capacity to return to pre-
epizootic numbers.

Little Snake Complex, Moffat County, Colorado

    Plague was documented at this complex in 1994 and 1995, following 
notable declines in populations in 1983-1987 and again in 1993 (USFWS 
1995, p. 11). In 1995, white-tailed prairie dog populations were 
estimated to equal 60 percent of levels prior to the 1983 epizootic 
(USFWS 1995, p. 11). Mapped occupied habitat declined by 92 percent 
between 1994 and 1999 (Seglund et al. 2006, p. iii). A portion of the 
complex representing 20 percent of the total area was remapped in 2009. 
Occupied habitat in that area was 11 percent of the area mapped in 1989 
(Ausmus 2010, pers. comm.). Population trends in the remaining 80 
percent of the complex were not yet assessed. No dusting (for flea 
control) is performed at this site. In summary, dramatic declines have 
occurred at the Little Snake Complex. We cannot document any recovery 
of the colony to date based on this limited information. The amount of 
occupied habitat has declined since the detection of plague in the mid-
1990s.

Wolf Creek Complex, Moffat and Rio Blanco Counties, Colorado

    Plague was suspected in 1985, due to white-tailed prairie dog 
declines. By 1994, the prairie dog population rebounded to pre-1985 
levels (Seglund et al. 2006, p. 20). In 2001, population numbers at the 
Wolf Creek ferret management area were 52 percent lower than in 1993-
1994. Populations remained stable through 2002 and 2003 (Seglund et al. 
2006, p. 93), and densities increased from 2004 to 2006 (Seglund and 
Schnurr 2009, p. 72).
    Wolf Creek was again heavily affected by plague in 2008, and the 
colony was treated with an insecticide for flea control in fall of 2008 
and 2009 (Holmes 2010a, pers. comm.). Active colonies remain in the 
complex. Quantitative population estimates will not be available until 
fall 2010 (Rustand 2010, pers. comm.). In summary, white-tailed prairie 
dog populations at the Wolf Creek Complex have shown dramatic declines 
followed by recoveries. Fluctuations are likely related to climatic 
conditions, disease, or a combination of both (Holmes 2008 in Seglund 
and Schnurr 2009, p. 72).

Dinosaur National Monument, Moffat County, Colorado

    A large white-tailed prairie dog colony occurred at the National 
Monument. No prairie dogs were observed on the colony in 2009. The 
colony is near Wolf Creek and may be affected by the same epizootic 
plague outbreak (Holmes 2010a, pers. comm.; Holmes 2010b, pers. comm.)

Montana

    Montana Fish, Wildlife and Parks (MFWP) has records of 31 white-
tailed prairie dog colonies historically occurring in the State (Begley 
2010b, pers. comm.). In 1997, only two colonies remained (FaunaWest 
1998 in Knowles 2002, p. 15). Three of these colonies were permanently 
lost to urbanization (Begley 2010b, pers. comm.). The cause behind the 
loss of the remaining 26 is unknown, although poisoning and plague are 
potential causes (Begley 2010c, pers. comm.). In 2006, the total number 
of colonies had increased to 10. In 2009, there were eight known active 
colonies (MFWP 2009a, p. 1; Hanebury 2009, pers. comm.). Plague was 
suspected by State biologists in the disappearance of one colony from 
2006-2009. We do not have population numbers or trend information for 
any of the Montana colonies.

Shiner Subcomplex, Uintah County, Utah

    White-tailed prairie dog population estimates in Shiner Basin were 
15,065 in 1997; 47,551 in 1998; 5,383 in 1999, and 13,707 in 2000 
(Seglund et al. 2006, p. 101). Total animals were counted on transects 
(not extrapolated for the area) between 2002 and 2007, and estimates 
were 5,475 animals in 2002; 4,284 in 2004; and 6,124 in 2007 (Maxfield 
2009, pers. comm.). In summary, white-tailed prairie dog populations in 
this area have fluctuated since 1997. The population appears to be 
lower than occurred in 1998, but has stabilized since 2002. Plague was 
suspected in this decline (Maxfield 2010, pers. comm.).

Cisco Desert, Southeastern Utah

    Mapping and burrow density estimates were conducted for white-
tailed prairie dogs from 1985 to 1986. The area was resurveyed using 
counts of individuals in 1991 and 1992, because of concerns that 
prairie dog colonies may be declining (Seglund et al. 2006, p. 30). 
Substantially more prairie dogs were counted during 1992 than in 1991 
(Seglund et al. 2006, p. 30). The population was estimated to be 50,000 
animals in 1997 followed by apparent declines in burrow activity in 
2001 (Wright 2006, p. 3). Between 1985 and 2006, burrows detected on 
transects dropped from 48.8 per ha (120.6 per ac) to 37.1 per ha (91.8 
per ac). Of the individual complexes, 14 increased in density while 31 
decreased (Wright 2006, p. 7).
    We interpret this to represent an overall decline in this area 
between 1985-2006, with marked fluctuations during this period. Plague 
is suspected in these declines, although drought also contributed 
(Wright 2006, p. 3). The white-tailed prairie dog is still considered 
widespread and abundant in this area (Wright 2006, p. 3).

Meeteetsee Complex, Park County, Wyoming

    Plague was first documented at Meeteetsee in 1985 (Biggins 2003, p. 
7). Large fluctuations in population estimates and active burrows occur 
at this complex. For example, total active burrows counted were 12,481 
in 1985; 7,644 in 1989; 6,782 in 1997; 12,428 in

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1990; and 16,736 in 1998 (Biggins 2003, p. 11). This complex was 
resampled in 2008, and numbers were higher than 1997, but still below 
1980s values (Biggins 2010, pers. comm.). In summary, individual 
colonies within the complex appear to suffer local, large population 
collapses followed by subsequent recoveries (Biggins et al. in press, 
p. 2). White-tailed prairie dogs continue to occupy the Meeteetsee 
Complex.

Shirley Basin/Medicine Bow Complex, Wyoming

    Population estimates for the complex are available, based on 
partial surveys. Therefore, numbers presented represent trends but are 
not directly comparable. Numbers in parenthesis are the percent of 
complex transected during that year. Population estimates were 30,389 
(31) in 1991; 14,551 (22) in 1993; 5,916 (6) in 1994; 19,876 (19) in 
1996; 6,547 (16) in 1998; 6,669 (16) in 2000; and 34,698 (8) in 2001 
(Seglund et al. 2006, p. 107). An additional 38,756 white-tailed 
prairie dogs also were recorded in 2001, in an area of the complex not 
surveyed in the previous years (Grenier et al. 2002, p. 23). Mapped 
occupied habitat increased 25 percent between 1991 and 2006 (Grenier et 
al. 2007, p. 133). Similar to other complexes, white-tailed prairie dog 
populations at Shirley Basin fluctuate dramatically, although direct 
comparisons are not appropriate due to yearly variation in transect 
sites. Plague was first documented at Shirley Basin in 1987 (Seglund et 
al. 2006, p. 36). In summary, plague likely impacted populations at 
Shirley Basin (Seglund et al. 2006, p. 36) and may be responsible for 
the fluctuating populations.
    The examples above clearly show that plague is present within 
white-tailed prairie dog colonies across the species' gross range, and 
is likely responsible for large population fluctuations and significant 
declines in complexes or portions of complexes. However, the colonies 
and complexes also show a capacity to recover after plague events. Some 
colonies decline and maintain lower numbers, perhaps due to enzootic 
plague (Little Snake, Montrose County, and Shiner Basin). Other 
complexes decline but either partially recover (Montana colonies, Wolf 
Creek, Cisco Desert) or fully recover (Shirley Basin/Medicine Bow).
    We do not know if the colonies and complexes recovered to 
population numbers that existed before plague was introduced because we 
do not have historical population information. We also do not know if 
the colonies and complexes exhibit pre-plague life-history patterns of 
mortality, reproduction, dispersal, and colonization. The available 
data indicates that white-tailed prairie dogs can continue to persist 
in the presence of plague. Population numbers in colonies or portions 
of colonies will continue to fluctuate widely, but retain the capacity 
to return to pre-epizootic numbers. Plague is demonstrated to cause 
this pattern in rodent species in Asia, where plague is native (Biggins 
and Kosoy 2001, p. 64).
    Continued persistence of colonies rangewide is impacted by many 
factors. The separation of colonies within complexes and distance 
between colonies may mediate the spread of plague. For example, the 
slow population decline witnessed at Meeteetsee between 1989 and 1997 
is likely the impact of plague affecting only a portion of the complex 
at a time (Biggins et al. in press, p. 2). Similarly, only a portion of 
Wolf Creek was affected by plague while the nearby Crooked Wash did not 
experience a concurrent decline (Holmes 2010b, pers. comm.). Finally, a 
population at the Arapaho National Wildlife Refuge in north-central 
Colorado did not decline concurrent with the decline at Wolf Creek 
(Hoogland 2010, pers. comm.).
    The ability for white-tailed prairie dogs to migrate may promote 
recolonization of colonies impacted by plague (Seglund et al. 2006, p. 
10). The ability to repopulate colonies depends on a mosaic of 
interconnected colonies; isolated colonies are less likely to support 
sufficient immigration for long-term persistence of plague-affected 
colonies (Seglund et al. 2006, p. 60). The complexes of Little Snake, 
Wolf Creek, Coyote Basin, Kennedy Wash, Snake John, and Shiner are 
considered separate but are all located in adjacent Uintah and Moffat 
Counties, and a reasonable amount of connectivity exists between them.
    Size also may be an important factor regulating persistence of 
individual colonies. Most of the sites discussed above are considered 
large complexes. In black-tailed prairie dogs, introduction of plague 
has resulted in colonies being consistently smaller than before first 
exposure to plague (Cully and Johnson 2008, p. 12). White-tailed 
prairie dog colonies may overall be smaller now when compared to pre-
plague levels. Small colonies not part of a large complex may be 
affected by plague at a higher intensity and may not have enough source 
individuals to recover. Smaller populations are generally accepted to 
be more vulnerable than larger populations (Shaffer 1981, p. 131). 
Larger groups of black-tailed prairie dogs had a higher survival 
probability after translocation than small groups (Robinette et al. 
1995, p. 872). We do not have data to assess specifically how plague 
operates in smaller, more isolated colonies. However, population 
viability modeling in black-tailed prairie dogs demonstrated continued 
persistence in small, fragmented colonies, assuming connectivity 
between populations (George et al. 2008, p. 1).
    The temporal nature of plague is an important factor when 
considering rangewide impacts (Seglund et al. 2006, p. 59). Plague does 
not impact all populations rangewide at the same time, with a 
predictable reoccurrence rate, or to the same intensity. Large plague-
related population declines were witnessed across the gross range, but 
in different years: Montana in 1997; Shirley Basin/Medicine Bow, 
Wyoming, in 1994 and 1998; Wolf Creek, Colorado, in 2001/2002 and 2008; 
and Uintah Basin in 1999 and 2003/2004.
    Some social and behavioral traits of white-tailed prairie dogs 
appear to favor their long-term persistence in a plague environment. 
White-tailed prairie dog colonies are less dense and more widely 
dispersed than black-tailed or Gunnison's prairie dog colonies, which 
may slow transmission rates (Cully 1993, pp. 40-41; Cully and Williams 
2001, pp. 898-899). White-tailed prairie dogs are less social when 
compared to other species; this trait may reduce transmission among 
individual animals (Hoogland 1981, pp. 252-253; Cully 1993, p. 40). 
Hibernation also contributes to slower transmission rates, although 
this may simply delay the onset of symptoms throughout all the colonies 
(Barnes 1993, p. 35).
    Some tools are available to control plague. Deltamethrin and 
pyraperm are two insecticides used to successfully control fleas on 
colonies of different prairie dog species (Seery et al. 2003, entire; 
Hoogland et al. 2004, entire). Use of these insecticides has increased 
the number of juvenile Utah prairie dogs weaned (Hoogland et al. 2004, 
p. 379) and resulted in higher survival rates for black-tailed, white-
tailed, and Utah prairie dogs (Biggins et al. in press, p. 5). 
Currently, insecticide use on white-tailed prairie dog colonies is 
limited to experimental use and when plague appears to be impacting 
colonies that support black-footed ferret reintroduction sites. Wolf 
Creek was treated in the summer and fall of 2009, in conjunction with 
that outbreak, and likely will be treated again in 2010. Other sites 
with black-footed ferrets include Coyote Basin, Snake John, Shirley 
Basin/ Medicine Bow, and Meeteetsee. Due to the expense of

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applying insecticide and the effects to non-target species, this method 
is only used when plague has already been detected.
    Experimental vaccine-laden baits are in development to immunize 
prairie dogs against plague. Black-tailed prairie dogs exposed to 
plague in a lab setting and fed vaccine baits experienced a high rate 
of survival (Mencher et al. 2004, pp. 5503-5504, Rocke et al. 2008, pp. 
933, 936). The effectiveness of the vaccine is scheduled for field 
testing over the next year. A systemic flea control bait also is under 
development (Poche et al. 2008, entire). The flea control bait reduces 
flea loads on animals, the primary vector in spreading plague in 
prairie dogs (Jachowski 2009, entire). While use of any of the above 
techniques, or combinations thereof, to manage plague has not been 
tested at the landscape level, these techniques show promise in the 
ability to manage plague.
    The occurrence of plague may be affected by climate change. As 
discussed in Factor A, Wyoming and Montana's yearly precipitation will 
become more variable while temperatures are expected to increase 
rangewide over the next 40 years. Plague outbreaks are significantly 
correlated with increased rainfall, particularly spring rainfall (Stapp 
et al. 2004, p. 237; Snall et al. 2008, pp. 245-246). However, plague 
outbreaks are negatively correlated with the yearly total number of hot 
days and overall increased temperatures (Stapp et al. 2004, p. 238; 
Snall et al. 2008, p. 245).
    Because climate change will likely produce variation in annual 
rainfall (Stapp et al. 2004, pp. 504-505), plague outbreaks may 
oscillate as these factors interact. Warmer winters in particular can 
result in increased plague transmission (Stapp et al. 2004, p. 236; 
Salkeld and Stapp 2008, p. 620). This effect is probably due to a range 
of factors including reduced hibernation (Rayor 1985, p. 195), better 
over-winter flea survival, and increased habitat productivity (Stapp et 
al. 2004, pp. 237-238). In the Colorado and Utah portions of the gross 
range, winter precipitation is expected to vary greatly from year to 
year, with some winters being very dry while others experience intense 
precipitation and flooding (Karl et al. 2009, p. 130). This variation 
may result in pulses of winter or early spring plague outbreaks during 
wetter years that are reduced in intensity over several years as hotter 
summer temperatures reduce plague in the environment. Plague 
occurrences are likely to decrease in black-tailed prairie dogs due to 
climate change effects (Sna ll et al. 2009, p. 505). Because it is 
believed that changing environmental conditions resulting from climate 
change is directly impacting plague transmission, we also may expect 
that plague will eventually decrease in white-tailed prairie dog 
habitats, concurrent with rising temperatures. Climate change may have 
less of an impact on plague levels if white-tailed prairie dogs exhibit 
a range shift as witnessed in some other species.
Tularemia and Monkeypox
    Tularemia (Francisella tularensis) and monkeypox (Orthopoxvirus 
spp.) are diseases that have had impacts on captive black-tailed 
prairie dogs associated with the pet trade, and a wild black-tailed 
prairie dog was reported as having fallen victim to West Nile virus 
(Seglund et al. 2006, p. 58). We have no information to indicate that 
any of these diseases are a concern for white-tailed prairie dogs at 
the population or species level.

Predation

    Many species prey upon the white-tailed prairie dog including 
black-footed ferrets (Mustela nigripes), hawks (Accipiter, Micronisus, 
Melierax, Urotriorchis and Megatriorchis spp.), eagles (Haliaeetus 
spp.), badgers (Taxidea taxus), and coyotes (Canus lupis) (Seglund et 
al. 2006, p. 58). However, predation is a natural occurrence for white-
tailed prairie dogs, and we have no information to indicate that 
predation is a threat to the species.
Summary of Factor C
    Plague occurs throughout the gross range of the white-tailed 
prairie dog. The rangewide and long-term effects of plague on prairie 
dog populations are not well understood. There is evidence of epizootic 
outbreaks of the disease and enzootic maintenance of the disease in 
prairie dog colonies. We acknowledge that populations are probably 
reduced from historic levels, and some colony behavioral functions, 
including migration and social interactions, may be impaired by plague. 
However, we have no evidence that demonstrates that plague has 
eliminated white-tailed prairie dogs from large portions of its gross 
range after over 70 years of exposure to the disease. Affected colonies 
have shown partial or complete recovery after plague events, and 
complexes continue to persist at the landscape level. Available 
information indicates that plague events are to some extent localized 
temporally and spatially, which may help mediate the species-level 
effects. Management actions are underway to research and implement 
plague control mechanisms, such as dusting, vaccines, and flea control, 
which should help alleviate colony population fluctuations and declines 
due to plague in the foreseeable future. As a result, we have 
determined that while plague is affecting the white-tailed prairie dog, 
it is not a significant threat that is now causing or projected to 
cause the species to be at risk of extinction.
    The available evidence does not indicate that other diseases or 
predation are sufficiently acting on the species to threaten the 
species with possible extinction now or in the foreseeable future. We 
conclude that the best scientific and commercial information available 
indicates that the white-tailed prairie dog is not now, or in the 
foreseeable future, threatened by disease or predation to the extent 
that listing under the Act as an endangered or threatened species is 
warranted at this time. Continued plague monitoring and research will 
be important for us to continue to assess the level of impact this 
disease plays in the long-term conservation of white-tailed prairie 
dogs. The development of a vaccine to protect prairie dog populations 
may help decrease future effects of plague.

Factor D. The inadequacy of existing regulatory mechanisms.

State Regulations and Private Land Management

Rangewide

    State laws and regulations may impact white-tailed prairie dog 
conservation by providing specific authority for white-tailed prairie 
dog conservation over lands which are directly owned by the State; 
providing broad authority to regulate and protect wildlife on all lands 
within their borders; and providing a mechanism for indirect 
conservation through regulation of threats to the species (e.g., 
noxious weeds). In general, States have broad authority to regulate and 
protect wildlife within their borders. All of the States within the 
range of the white-tailed prairie dog have State school trust lands 
that they manage for income to support their schools. We are unaware of 
any specific regulations to ensure that the management of the State 
trust lands is consistent with the needs of white-tailed prairie dog. 
Thus there are currently no regulatory mechanisms on State trust lands 
to ensure conservation of the species.
    Environmental planning regulations establish environmental quality 
as an essential component of land use and project planning and provide 
a structured, analytical frame work to make decisions that balance

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environmental and economic factors (Council on Environmental Quality 
(CEQ) 1997, p.11). The implementation of the National Environmental 
Policy Act (NEPA, 42 U.S.C. 4321 et seq.) has improved the quality of 
projects and reduced impacts to the environment in the Federal planning 
process (CEQ 1997, p. 17). Within the range of the white-tailed prairie 
dog, only Montana has NEPA-like environmental planning regulations (CEQ 
2009, entire). Because activities on private and State lands in 
Colorado, Utah, and Wyoming are not subject to environmental review, 
they may have a greater impact to white-tailed prairie dogs than 
similar activities on Federal lands.
    Potential impacts to the species that can be managed by State or 
private entities include recreational shooting, shooting to protect 
agricultural interests, and oil and gas development on non-Federal 
mineral estates. In addition, the State wildlife agencies can 
contribute to species conservation by supporting research and 
monitoring efforts, including plague management.
    The Western Association of Fish and Wildlife Agencies (WAFWA) 
coordinates management efforts of the white-tailed prairie dog and 
other species among the western States. The WAFWA prepared a Rangewide 
Conservation Agreement for the White-Tailed Prairie Dog in 2006 
(Seglund et al. 2006, entire). The objectives of the conservation 
agreement include identification and monitoring of the species' status 
and distribution, public education, identification and implementation 
of priority research needs, and creation of State management plans 
(Seglund et al. 2006, p. 3). The conservation agreement provides 
expertise, recommendations, and coordination of funding for the 
conservation of the species, but does not provide regulatory 
protection.
    Private lands comprise a large portion of the predicted range of 
the species. Private landowners can control prairie dogs on their land 
as necessary in all States. However, general public access and hunting 
on private lands throughout the gross range are limited by trespass 
laws. We have no evidence that the control activities or policies of 
individual private landowners are threatening the species.
    Oil and gas development occurs across the gross range of the 
species, including on lands managed by the States. We are unaware of 
any regulations or protection measures for white-tailed prairie dogs on 
these lands. However, based on available information, we do not 
consider oil and gas development a factor that significantly threatens 
the white-tailed prairie dog (see Factor A. Oil and Gas Exploration and 
Development, above).

Colorado

    The Colorado Department of Wildlife (CDOW) released a Statewide 
Conservation Strategy outlining the management of white-tailed and 
Gunnison's prairie dogs in fall 2009 (Seglund and Schnurr 2009, 
entire). This document guides the development of conservation 
strategies for the three white-tailed prairie dog Individual Population 
Areas (IPAs) (see Distribution and Abundance). Local action plans with 
individual goals and objectives are under development for each IPA. The 
Statewide Conservation Strategy provides management priorities and 
guidance for the species, but does not provide regulatory protection.
    All prairie dog species are classified as small game in Colorado. A 
small game license is required for shooting prairie dogs, with the 
exception of private landowners and their immediate family members or 
designees, who may kill prairie dogs causing damage on their lands 
(CDOW 2009, p. 10). Shooting of prairie dog species is not permitted on 
public land between March 1 and June 15 (CDOW 2009, p. 10), providing 
protection during the sensitive breeding and rearing time periods.
    The Colorado Oil and Gas Conservation Commission (COGCC) had a 
policy encouraging voluntary cooperation among oil and gas operators in 
preventing and mitigating potential impacts to wildlife (COGCC 1996, 
entire). In 2009 the state legislature passed rules requiring oil and 
gas companies to consult with state wildlife officials regarding the 
impacts of their proposed development to wildlife. The rules promote 
best management practices and allow the state to set reasonable 
conditions of development in sensitive wildlife areas (COGCC 2009, 
entire). Application of these rules to white-tailed prairie dogs in 
particular is then up to state wildlife officials. Given the recent 
passing of these rules, it is unknown if they will be applied to 
prairie dog species.

Montana

    White-tailed prairie dogs are identified as a Species of Greatest 
Conservation Need (Tier 1) in Montana's Comprehensive Fish and Wildlife 
Conservation Strategy (MFWP 2009a, p. 1). The State defines this as a 
species whose needs must be specifically addressed, whether through 
focus areas, community types, or individually (MFWP 2005, p. 188). This 
designation gives the State statutory authority to manage the species. 
For example, under this authority, MFWP translocates white-tailed 
prairie dogs in an effort to establish new colonies. Translocations 
began in 2007, and are expected to continue until at least 2011.
    White-tailed prairie dogs in Montana were once protected from all 
shooting, but the regulation protecting them has lapsed, and they are 
currently unprotected. A license is not required to hunt prairie dogs 
in Montana.

Utah

    The white-tailed prairie dog is listed as a Species of Concern in 
Utah, defined by the State as a wildlife species for which there is 
credible scientific evidence to suggest a threat to continued 
population viability within the State (UDWR 2007, p. 1). Species are 
provided this designation in order to encourage management actions and 
prevent the species from declining to the point where listing is 
necessary. Utah completed a conservation agreement and Strategy for 
white-tailed and Gunnison's prairie dogs in 2007. Under the 
conservation agreement, the State committed to conduct occupancy 
surveys in an effort to detect population declines and respond with 
appropriate management actions (Lupis et al. 2007, pp. 22-23). The 
Statewide conservation strategy provides management priorities and 
guidance for the species, but does not provide regulatory protection.
    No license is required to hunt prairie dogs in Utah (UDWR 2009, p. 
1). However, prairie dog shooting is not allowed between April 1 and 
June 15 (UDWR 2009, p. 4), providing the species with protection during 
sensitive breeding and rearing periods. In addition, a year-round 
shooting closure is implemented in the Coyote Basin black-footed ferret 
reintroduction area (7,604 ha (18,789 ac)).

Wyoming

    White-tailed prairie dogs are considered a Species of Greatest 
Conservation Need: Native Species Status 4 in Wyoming. Species are 
given this designation when habitat is restricted or threatened, or 
population numbers are declining and unknown. The species was given a 
status level of 4 due to unknown population trends and restricted or 
vulnerable but not declining habitat (Wyoming Game and Fish Commission 
1998, p. 238). No conservation agreement is in place for the species in 
Wyoming. State biologists participate in prairie dog surveys and 
management under the guidance of WAFWA.

[[Page 30359]]

    Shooting of white-tailed prairie dogs is permitted in Wyoming 
without a license (WGFC 1998, pp. 52-54), and there are no seasonal 
closures. State biologists have witnessed no negative effects from 
removing a seasonal closure on the Shirley Basin population (Grenier 
2009, pers. comm.); therefore, it seems unlikely that lack of closures 
is having a population-level effect.
    In summary, the States are actively involved in prairie dog 
research and monitoring efforts under direction of the WAFWA 
Conservation Agreement and State-specific species management plans. The 
information obtained through these efforts will be valuable for future 
efforts to conserve the species and avoid threats. Recreational 
shooting of prairie dogs is not considered a threat to the species (see 
Factor B. Overutilization, above). However, seasonal shooting closures 
are implemented on a site-specific basis in Colorado and Utah. The lack 
of environmental planning and protection for the species from all land 
use activities on non-Federal land, including non-Federal oil and gas 
leases, may impact the species in the future. However, at this time the 
information we do have does not indicate that threats from land use 
activities are sufficient to require regulatory mechanisms now or in 
the foreseeable future (see Factor A., above).
Federal Management Authority
    Potential impacts to the species that could be managed by the 
Federal land management agencies include oil and gas development, 
grazing, fire suppression, poisoning, and recreational shooting.

Bureau of Land Management

    The Federal Land Policy and Management Act of 1976 (FLPMA) (43 
U.S.C. 1701 et seq.) is the primary Federal law governing most land 
uses on BLM lands. Section 102(a)(8) of FLPMA specifically recognizes 
wildlife and fish resources as being among the uses for which these 
lands are to be managed. The BLM considers the needs of wildlife, 
including the white-tailed prairie dog, when conducting activities in 
their habitat. Typically, this means the impacts to these species are 
considered during project planning stages and conservation measures may 
be included at the discretion of the agency biologists. In addition, 
the BLM is required to meet environmental planning requirements under 
NEPA (73 FR 61292), which requires reviewing the effects of actions on 
the environment (including wildlife) before implementation.
    The BLM's resource management plans (RMPs) are the basis for all of 
its actions and authorizations involving BLM-administered lands and 
resources. The RMPs establish allowable resource uses, general 
management practices, program constraints and other parameters of 
project design (43 CFR 1601.0-5(k)). These plans provide a framework 
and programmatic guidance for site-specific activity plans. In 
addition, BLM management plans may include conservation measures to 
protect the species. These measures vary between State and field 
offices.
    Site-specific plans likely to affect white-tailed prairie dogs 
typically include livestock grazing, oil and gas field development, 
wildlife habitat management, and other land use activities. The 
potential effects of these activities on the species' habitat are 
addressed under Factor A, above.
    In Colorado's Grand Valley/Uncompahgre IPA, BLM lands have special 
designations offering protections, such as a yearly closure to 
motorized and non-motorized travel restrictions to designated routes 
only, and withdrawal from all forms of mineral entry, including oil and 
gas leasing (Seglund and Schnurr 2009, p. 55). The BLM-owned portion of 
the Northwest IPA's white-tailed prairie dog's gross range is 
considered high or medium potential for oil and gas development. The 
RMPs stipulating activities in this IPA are undergoing revisions to 
address oil and gas development and associated impacts (Seglund and 
Schnurr 2009, p. 61). We do not know if the RMP revisions will include 
conservation measures to minimize the effects of oil and gas 
development to white-tailed prairie dogs. At this time, we do not 
believe oil and gas development to be a significant threat to the 
species (see Factor A. Oil and Gas Exploration and Development, above). 
However, the ability to adequately monitor the species in energy 
development areas will be important for our long-term ability to 
minimize impacts.
    In Utah, the BLM updated several field office RMPs in 2007. These 
updated RMPs included a stipulation to avoid surface-disturbing 
activities within 201 m (660 ft) of white-tailed prairie dog colonies 
in known prairie dog habitat (BLM 2008a, p. K:13). An exception may be 
granted if impacts can be mitigated or if there is no other reasonable 
location to develop the lease. This stipulation is included in the 
management plans that apply to white-tailed prairie dog colonies near 
Vernal, Richfield, Price, and Moab. No exceptions to this stipulation 
have yet been made in the Moab or Price field offices. Vernal field 
office staff report four exceptions to this stipulation. In all 
examples, disturbance was limited to the edge of a colony because no 
other alternatives were available (McDonald 2010, pers. comm.). The RMP 
governing activities in Rich County has not been amended to include a 
stipulation to protect white-tailed prairie dog habitat (Madsen 2009, 
pers. comm.). However, this area comprises a very small amount of 
occupied habitat in Utah, and any impacts to this area are unlikely to 
produce population-level effects.
    In Wyoming, no extra protections are extended to white-tailed 
prairie dogs on BLM land, although control efforts (described below in 
Factor E) are not permitted except in the case of extensive resource 
damage or a threat to human health and safety (Keefe 2009, pers. 
comm.). Given the extent of oil and gas development in this State, lack 
of regulations on BLM land could be detrimental to the species, but the 
available evidence does not suggest that impacts are rising to a 
significant population-level threat (see Factor A. Oil and Gas 
Exploration and Development, above).

U.S. Forest Service (USFS)

    The USFS considers the white-tailed prairie dog to be a Region 2 
sensitive species, which requires USFS to consider the presence of the 
species and recommend mitigation when planning projects that may affect 
the species (Seglund and Schnurr 2009, p. 55). Controlling prairie dogs 
with toxicants is banned or closely controlled on USFS lands (Seglund 
et al. 2006, p. 62). The USFS manages less than 1 percent of the total 
species' gross range, so their management strategies are unlikely to 
impact the species rangewide significantly.

U.S. Fish and Wildlife Service

    The Service manages over 500 National Wildlife Refuges and their 
satellites, but only about 7,975 ha (19,706 ac) fall within the white-
tailed prairie dog's predicted range (Seglund et al. 2006 pp. 98, 104, 
109). Management of this species is not addressed on these lands 
(Seglund et al. 2006, p. 62). Control of prairie dogs through toxicants 
on these lands is banned or closely controlled (Seglund et al. 2006, p. 
62). Given the small amount (less than 1 percent) of predicted habitat 
managed by us, the available information does not suggest that our 
management practices are having a significant impact on the species.

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National Park Service

    The NPS preserves unimpaired the natural and cultural resources and 
values of the national park system for the enjoyment, education, and 
inspiration of this and future generations. This agency manages 13,393 
ha (33,096 ac) of the white-tailed prairie dog's predicted range 
(Seglund et al. 2006, pp. 98, 104, 109). Management of this species is 
not addressed on these lands (Seglund et al. 2006, p. 62). Control of 
prairie dogs through toxicants on these lands is banned or closely 
controlled (Seglund et al. 2006, p. 62). Given the small amount (less 
than 1 percent) of predicted habitat managed by this agency, the 
available information does not suggest that NPS management practices 
are having a significant impact on the species.

Tribal Lands

    The Bureau of Indian Affairs (BIA) administers 135,376 ha (334,523 
ac) of land within the white-tailed prairie dog's predicted range 
(Seglund et al. 2006, pp. 98, 104, 109). Additional land owned by 
Tribes or Tribal members may have been included under the calculations 
for private land. We are unaware of any official policies from the BIA 
or Tribal councils regarding protection of white-tailed prairie dogs on 
BIA-administered or Tribally owned lands. Given the small amount (less 
than 1 percent) of predicted habitat managed by Tribes, the available 
informationdoes not suggest that BIA management practices are having a 
significant impact on the species.
    In summary, Federal agencies have very few regulations for the 
protection of this species. The oil and gas surface use restrictions in 
the State of Utah likely help minimize the impacts of oil and gas 
development to white-tailed prairie dogs. The lack of protection 
measures for the species elsewhere may impact the species in the 
future; however, at this time the available information does not 
indicate that factor significantly threatens the species in the 
foreseeable future (see Factor A. Oil and Gas Exploration and 
Development, above). Poisoning also is banned or closely controlled on 
Federal lands (see Factor E. Poisoning, below, for further discussion).
Summary of Factor D
    All States are involved in active management of the species. The 
States' conservation agreements and strategies, while not regulatory 
documents, contain direction to help mitigate threats to the species.
    Potential threats for which regulatory mechanisms may play a role 
include oil and gas development, grazing, fire suppression, poisoning, 
and recreational shooting. We have determined that these factors do not 
rise to the level of a significant threat to the white-tailed prairie 
dog or its habitat rangewide.
    Our evaluation determined that these land uses may impact white-
tailed prairie dogs on a localized basis. Existing regulatory 
mechanisms are adequate to reduce impacts at these localized levels. 
For example, seasonal shooting closures in Colorado and Utah are 
protecting white-tailed prairie dog populations in some areas during 
sensitive breeding and rearing time periods. The BLM's RMPs in Utah 
contain recommendations to avoid surface disturbance during oil and gas 
development, although this does not mediate the impact of habitat 
fragmentation from this threat. In addition, the historical threat of 
poisoning was curtailed when Federal regulation of pesticides was 
enacted, and is generally not permitted on Federal lands.
    Further coordination between State and Federal agencies would be of 
benefit to this species, particularly in managing habitat 
fragmentation. More management would be of benefit to the species, but 
the available evidence does not indicate that limited management 
strategies are a significant threat to the species.
    We conclude that the best scientific and commercial information 
available indicates that the white-tailed prairie dog is not now, or in 
the foreseeable future, threatened by inadequate regulatory mechanisms 
to the extent that listing under the Act as an endangered or threatened 
species is warranted at this time.

Factor E. Other natural or manmade factors affecting its continued 
existence.

    The following potential natural or manmade factors may affect the 
white-tailed prairie dog: (1) Poisoning, and (2) competition with 
Wyoming ground squirrels. These factors are further discussed below.
Poisoning
    Poisoning of white-tailed prairie dogs has historically occurred 
throughout the species' gross range (Seglund et. al 2006, p. 63). The 
USDA Biological Survey and the Agriculture Appropriations Act of 1915 
(38 Stat. 1111) planned and authorized a Westside Plan to eliminate 
prairie dogs across western rangelands (Oakes 2000 in Seglund and 
Schnurr 2009, p. 140). Prairie dog poisoning campaigns began in all 
States across the gross range of the white-tailed prairie dogs by 1919 
(Seglund and Schnurr 2009, p. 140).
    The population-level impact of this practice is difficult to 
quantify due to our lack of knowledge of the species' historical 
distribution and our lack of information on the exact locations of 
poisoning efforts (Seglund and Schnurr 2009, p. 140). However, the 
extent of poisoning for all prairie dog species was extensive. For 
example, from 1915 to 1964, Colorado poisoned an area of 9,380,191 ha 
(23,178,959 ac), which was occupied by the Gunnison, black-tailed, and 
white-tailed species of prairie dogs (Forrest 2002 in Seglund and 
Schnurr 2009, p. 141). Black-tailed prairie dogs were the main target 
of eradication campaigns due to their visibility on the landscape, but 
Gunnison and white-tailed prairie dogs also were poisoned (Seglund and 
Schnurr 2009, p. 140).
    Poisoning in all States became less common after Federal regulation 
of pesticides was enacted (Seglund et al. 2006, p. iv). State and 
Federal agencies are rarely involved in control efforts unless human 
health and safety are at risk. The BLM, in particular, has a 
restriction against poisoning prairie dogs unless required for human 
health and safety or if resource damage meets specified requirements. 
Control of white-tailed prairie dogs in this manner is rare, with the 
agency only reporting one small area currently under control (Keefe 
2009, pers. comm.). Individual landowners may still control prairie 
dogs on their private property.
    Poison applications can be an effective means to control prairie 
dog population size. Baited poisons can result in 75 to 85 percent 
mortality, and fumigants can result in 95-percent mortality of prairie 
dog populations when properly applied (Seglund and Schnurr 2009, 
p.141). Although poisoning was historically widespread, there is no 
information available to indicate that poisoning occurs at more than a 
localized scale today. We were unable to quantify amount of toxicants 
sold for white-tailed prairie dog control. The States within the gross 
range of the white-tailed prairie dog do not compile records of 
pesticide sales. There are 103 licensed dealers of restricted use 
toxicants in Utah and 288 licensed dealers in Colorado. The WGFD staff 
surveyed Wyoming dealers in 2003, and determined that toxicant sales 
were too small to warrant tracking, with a total less than would be 
required to treat 400 ha (1,000 ac) per year (Grenier 2009, pers. 
comm.).
    White-tailed prairie dog biology may provide some protection from 
poisoning. Because they inhabit less dense, widely distributed 
colonies, they

[[Page 30361]]

do not attract the amount of negative attention associated with black-
tailed prairie dogs (Knowles 2002, p. 2; Grenier 2009, pers. comm.). In 
addition, the widespread nature of white-tailed prairie dog colonies 
makes control through the use of toxicants very labor intensive and 
unsuitable for widespread control. Black-tailed prairie dogs are known 
to rebound rapidly after control efforts (Seglund and Schnurr 2009, p. 
140). White-tailed prairie dogs may have this capability as well 
(Seglund and Schnurr 2009, p. 140), particularly because they reproduce 
at a younger age than black-tailed prairie dogs.
    In summary, today, poisoning generally occurs only on private land 
for site-specific control purposes rather than wide-spread population 
eliminations (Seglund et al. 2006, p. 65). White-tailed prairie dogs 
may have the capability to rebound from control efforts. Their 
scattered distribution and behavioral mechanisms may provide them with 
some protection from poisoning efforts. Therefore, we do not believe 
poisoning to be a significant threat to the species now or in the 
foreseeable future.
Competition
    Competition may occur between Wyoming ground squirrels and white-
tailed prairie dogs (Seglund and Schnurr 2009, p. 100). Their diets 
overlap and their burrows are often interspersed. Wyoming ground 
squirrels are found in some areas where plague has decimated Gunnison's 
prairie dogs (Seglund and Schnurr 2009, p. 100). However, white-tailed 
prairie dogs were observed to chase and kill Wyoming ground squirrels 
(Cooke 1990, p. 275). Given their size advantage and aggression, it 
seems unlikely that prairie dogs would be excluded by Wyoming ground 
squirrels (Hoogland 2009, pers. comm.). In addition, ground squirrels 
are vulnerable to plague, and epidemics reduce their numbers alongside 
prairie dogs. At this time there is no evidence to suggest that there 
may be other competitors or that competition is a threat to the white-
tailed prairie dog.
Summary of Factor E
    Available evidence does not suggest that control of prairie dogs 
through poisoning is a major or increasing threat to the while-tailed 
prairie dog. It seems unlikely that competition with Wyoming ground 
squirrels would threaten the species' persistence.
    We conclude that the best scientific and commercial information 
available indicates that the white-tailed prairie dog is not now, or in 
the foreseeable future, threatened by other natural or manmade factors 
affecting its continued existence, to the extent that listing under the 
Act as an endangered or threatened species is warranted at this time.

Finding

    As required by the Act, we considered the five factors in assessing 
whether the white-tailed prairie dog is endangered or threatened 
throughout all of its range. We have carefully examined the best 
scientific and commercial information available regarding the past, 
present, and future threats faced by the white-tailed prairie dog. We 
reviewed the petition, information available in our files, and other 
available published and unpublished information, and we consulted with 
recognized white-tailed prairie dog experts and other Federal, State, 
and tribal agencies.
    In considering what factors might constitute threats, we must look 
beyond the mere exposure of the species to the factor to determine 
whether the species responds to the factor in a way that causes actual 
impacts to the species. If there is exposure to a factor, but no 
response, or only a positive response, that factor is not a threat. If 
there is exposure and the species responds negatively, the factor may 
be a threat and we then attempt to determine how significant a threat 
it is. If the threat is significant, it may drive or contribute to the 
risk of extinction of the species such that the species warrants 
listing as endangered or threatened as those terms are defined by the 
Act. This does not necessarily require empirical proof of a threat. The 
combination of exposure and some corroborating evidence of how the 
species is likely impacted could suffice. The mere identification of 
factors that could impact a species negatively is not sufficient to 
compel a finding that listing is appropriate; we require evidence that 
these factors are operative threats that act on the species to the 
point that the species meets the definition of endangered or threatened 
under the Act.
    We identified and evaluated the risks of the present or threatened 
destruction, modification, or curtailment of the habitat or range of 
the white-tailed prairie dog: (1) Oil and gas exploration and 
development; (2) oil shale, tar sands, and other minerals, (3) 
renewable energy development--wind and solar; (4) urbanization; (5) 
agricultural land conversion; (6) grazing; (7) fire occurrence and 
suppression; (8) invasive plant species; and (9) climate change. While 
oil and gas development is impacting the species, we have no evidence 
that it will significantly threaten the species in the foreseeable 
future. We concluded that oil shale, tar sands, and other minerals; 
renewable energy development; urbanization; agricultural land 
conversion; grazing; fire suppression; invasive plant species; and 
climate change are not significant threats to the species now or in the 
foreseeable future. Based on our review of the best available 
information, we find that the present or threatened destruction, 
modification, or curtailment of the white-tailed prairie dog habitat or 
range is not a significant threat now or in the foreseeable future.
    We identified and evaluated the risks from overutilization for 
commercial, recreational, scientific, or educational purposes. While 
shooting results in some individual mortality and may affect easily 
accessible colonies, available evidence does not indicate that the 
magnitude or intensity is enough to significantly threaten the species 
rangewide. Therefore, we conclude that the white-tailed prairie dog is 
not significantly threatened by overutilization for commercial, 
recreational, scientific, or educational purposes now or in the 
foreseeable future.
    We found that plague impacts populations throughout the species' 
range. We determined that colonies and complexes persist in the post-
plague environment, which demonstrates a rangewide resiliency to the 
disease. We determined that the species' life-history characteristics 
provide some protection from the spread of plague and that epizootic 
plague only affects a small portion of the range at one time. The 
threat of plague may decrease across the range with the impacts of 
management and climate change. Tularemia, monkey-pox, and West Nile 
virus are not considered threats to the species. Additionally, we note 
that while white-tailed prairie dogs are prey for numerous species, 
available information does not indicate that predation has an overall 
adverse effect on the species. Therefore, we find that neither disease 
nor predation is a significant threat to the species now or in the 
foreseeable future.
    Based on our analysis of the existing regulatory mechanisms, we 
determined the States are actively involved in managing the species 
through conservation agreements and strategies. Although these 
agreements are not regulatory, they provide an important mechanism for 
conservation, monitoring, and research efforts. The existing regulatory 
mechanisms in place on State and Federal lands are limited. However, we 
determined in the evaluation that other threats would not adversely 
affect the white-tailed prairie

[[Page 30362]]

dog now or within the foreseeable future. Additionally, the white-
tailed prairie dog receives some protection from shooting under State 
laws in Colorado and Utah, and from oil and gas development in Utah. 
Therefore, based on our review of the best available scientific 
information, we conclude that inadequacy of existing regulatory 
mechanisms is not a significant threat to the species now or in the 
foreseeable future.
    We also assessed the potential risks to white-tailed prairie dogs 
from poisoning and interspecific competition, and we find that there is 
no evidence that indicates these factors significantly threaten the 
continued existence of white-tailed prairie dog now or in the 
foreseeable future.
    We determined that energy development, urbanization, grazing, fire 
suppression, agricultural conversion, recreational shooting, poisoning, 
invasive plant species, and plague may impact the species in at least 
localized areas. White-tailed prairie dogs were impacted throughout 
history by each of these factors. We believe that, collectively, these 
activities have resulted in the presumed reduced abundance of white-
tailed prairie dog from historical levels. We also believe that the 
ecological function of this species within western landscapes has been 
altered from its historical function. Many of these factors (grazing, 
urbanization, fire suppression, agricultural land use conversion, and 
poisoning) were at much greater magnitude in the past and are not 
currently impacting species with the same intensity. Other threats (oil 
and gas development, climate change, shooting, plague, and invasive 
plant species) can be expected to continue into the future. Of these, 
we consider plague and oil and gas development to have the greatest 
potential for cumulative impacts. Yet some of the most robust and 
resilient colonies exist in areas where both of these potential threats 
occur. Therefore, we do not believe these factors will cumulatively 
threaten the continued existence of white-tailed prairie dog now or in 
the foreseeable future.
    Our review of the information pertaining to the five threat factors 
does not support a conclusion that there are independent or cumulative 
threats of sufficient imminence, intensity, or magnitude that would 
cause substantial losses of population distribution or viability of the 
white-tailed prairie dog that would result in the species being at risk 
of extinction. Therefore, we do not find that the white-tailed prairie 
dog is currently in danger of extinction (endangered), nor do we find 
it is likely to become endangered within the foreseeable future 
(threatened), throughout its range. Therefore, listing the species as 
endangered or threatened under the Act is not warranted at this time.

Distinct Vertebrate Population Segments

    After assessing whether the species is endangered or threatened 
throughout its range, we next consider whether any distinct vertebrate 
population segment (DPS) exists and meets the definition of endangered 
or is likely to become endangered in the foreseeable future 
(threatened).
    Under the Service's Policy Regarding the Recognition of Distinct 
Vertebrate Population Segments Under the Endangered Species Act (61 FR 
4722, February 7, 1996), three elements are considered in the decision 
concerning the establishment and classification of a possible DPS. 
These are applied similarly for additions to or removal from the 
Federal List of Endangered and Threatened Wildlife. These elements 
include:
    (1) The discreteness of a population in relation to the remainder 
of the taxon to which it belongs;
    (2) The significance of the population segment to the taxon to 
which it belongs; and
    (3) The population segment's conservation status in relation to the 
Act's standards for listing, delisting (removal from the list), or 
reclassification (i.e., is the population segment endangered or 
threatened).

Discreteness

    Under the DPS policy, a population segment of a vertebrate taxon 
may be considered discrete if it satisfies either one 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.
    (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.
    The predicted range of the white-tailed prairie dog encompasses 
13,066,887 ha (32,288,981 ac) (Seglund et al. 2006, p. 91). We do not 
consider any population segment of white-tailed prairie dog to be 
markedly separated from other populations of the same taxon as a 
consequence of physical, physiological, ecological, or behavioral 
factors. As a colonial species, white-tailed prairie dogs are naturally 
distributed across the landscape in a discontinuous fashion. Occupied 
habitat changes rapidly, shifting on a landscape scale (Seglund et al. 
2006, p. iii). The species spans Colorado, Utah, Wyoming, and Montana. 
Available information suggests while population areas within Colorado 
and Utah are not continuous with other populations areas within the 
same State, they are continuous between these States and with 
populations in Wyoming. Therefore, we do not consider any of these 
areas to be physically discrete. Because discontinuous distribution is 
the ``baseline'' condition for the species, for us to consider any 
geographic discontinuity as being evidence of marked separation (i.e., 
discreteness) under the DPS policy, we would need the best available 
information to indicate that the amount of discontinuity is over and 
above what is considered to be normal for the species.
    We do not have detailed mapping of occupied habitat throughout the 
range of the species. We recognize the likely occurrence of some small, 
isolated white-tailed prairie dog colonies, but have very limited 
information available that identifies their locations. Therefore, we 
looked for other measures of discontinuity, such as measures of genetic 
or morphological differences as guided by the DPS policy, to determine 
whether any populations showed evidence of marked separation. The 
information available does not indicate that any ecological or physical 
factors have produced population segments that express any genetic or 
morphological discontinuity due to separation from other prairie dog 
populations. Gene flow via dispersal and migration may maintain genetic 
diversity in prairie dog species or help restore genetic diversity in 
prairie dog populations following plague epizootics (Trudeau et al. 
2004, p. 206). The available information does not suggest that 
populations differ genetically or morphologically.
    We determine, based on a review of the best available information, 
that no population segment of the white-tailed prairie dog meets the 
discreteness conditions of the 1996 DPS policy. Therefore, no 
population segment qualifies as a DPS under our policy and is not a 
listable entity under the Act.
    The DPS policy is clear that significance is analyzed only when a 
population segment has been identified as discrete. Since we found that 
no population segment met the

[[Page 30363]]

discreteness element and, therefore, no population segments qualify as 
a DPS under the Service's DPS policy, we will not conduct an evaluation 
of significance.

Significant Portion of the Range Analysis

    We evaluated the white-tailed prairie dog's predicted range in the 
context of whether any potential threats are concentrated in one or 
more areas of the projected range, such that if there were concentrated 
impacts, those white-tailed prairie dog populations might be 
threatened, and further, whether any such population or complex might 
constitute a significant portion of the range. The potential threat 
factors we evaluated for possible geographic concentration were the 
most substantial factor(s) affecting the species (in this case, plague 
and habitat fragmentation due to oil and gas development).

Plague

    We regard sylvatic plague as the most substantial factor affecting 
the white-tailed prairie dog. The disease is present throughout the 
species' range. We consider the entire range of the species to be 
operating in a post-plague environment. We documented variation between 
colonies and complexes in their ability to maintain observed peaks of 
abundance. However, this variation occurred in every portion of the 
range, and was not concentrated in any geographic location. At this 
time, there is no evidence to suggest that plague affects portions of 
the range differently, or will in the foreseeable future.

Oil and Gas Development

    Oil and gas development is a widespread land use within the 
species' range. Our analysis indicated a concentration of oil and gas 
activity in Uintah County, Utah, and the Northwest IPA, located in 
adjacent Moffat, Mesa, and Rio Blanco Counties in Colorado. A similar 
concentration can be visually observed in Sweetwater County, Wyoming 
(Hotze 2010, p. 11). However, some of the most robust and resilient 
colonies are found within these areas of concentrated development. The 
available evidence does not indicate that oil and gas development 
activities are negatively impacting the species (see Factor A. Oil and 
Gas Exploration and Development). Given these factors, we do not 
believe the regional concentration of oil and gas development is 
threatening the species in these portions of its range.
    On the basis of this review, we have determined that the magnitude 
and imminence of threats do not indicate that the white-tailed prairie 
dog is in danger of extinction, or likely to become endangered, 
throughout all or a significant portion of its range, within the 
foreseeable future. The species also does not meet the elements of our 
1996 DPS Policy that would result in a DPS designation for any segment 
of the population. We conclude that no Significant Portion of the Range 
(SPR) exists for the white-tailed prairie dog. We do not find that the 
species is in danger of extinction now, nor is it likely to become 
endangered within the foreseeable future, throughout all or a 
significant portion of its range. Therefore, listing the white-tailed 
prairie dog as endangered or threatened under the Act is not warranted 
at this time.
    We request that you submit any new information concerning the 
status of, or threats to, the white-tailed prairie dog to our Utah Fish 
and Wildlife Office (see ADDRESSES) whenever it becomes available. New 
information will help us monitor the white-tailed prairie dog and 
encourage its conservation. If an emergency situation develops for the 
white-tailed prairie dog or any other species, we will act to provide 
immediate protection.

References Cited

    A complete list of references cited is available on the Internet at 
http://www.regulations.gov and upon request from the Utah Field Office 
(see ADDRESSES).

Authors

    The primary authors of this document are the staff members of the 
Utah Field Office, West Valley City, Utah.

Authority

    The authority for this section is section 4 of the Endangered 
Species Act of 1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: May 14, 2010
Daniel M. Ashe,
Acting Director, Fish and Wildlife Service.
[FR Doc. 2010-12599 Filed 5-28-10; 8:45 am]
BILLING CODE 4310-55-S