Endangered and Threatened Wildlife and Plants; 12-month Finding on a Petition to List the American Pika as Threatened or Endangered, 6438-6471 [2010-2405]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 75, Number 26 (Tuesday, February 9, 2010)]
[Proposed Rules]
[Pages 6438-6471]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-2405]



[[Page 6437]]

-----------------------------------------------------------------------

Part II





Department of the Interior





-----------------------------------------------------------------------



Fish and Wildlife Service



-----------------------------------------------------------------------



50 CFR Part 17



Endangered and Threatened Wildlife and Plants; 12-month Finding on a 
Petition to List the American Pika as Threatened or Endangered; 
Proposed Rule

Federal Register / Vol. 75, No. 26 / Tuesday, February 9, 2010 / 
Proposed Rules

[[Page 6438]]


-----------------------------------------------------------------------

DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[FWS-R6-ES-2009-0021
MO 92210-0-0010]


Endangered and Threatened Wildlife and Plants; 12-month Finding 
on a Petition to List the American Pika as Threatened or Endangered

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of 12-month petition finding.

-----------------------------------------------------------------------

SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
12-month finding on a petition to list the American pika (Ochotona 
princeps) as threatened or endangered under the Endangered Species Act 
of 1973, as amended. After review of all available scientific and 
commercial information, we find that listing the American pika, at the 
species level or any of the five recognized subspecies (O. p. princeps, 
O. p. saxatilis, O. p. fenisex, O. p. schisticeps, and O. p. uinta), 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 American pika, the five subspecies, or its habitat at any time.

DATES: The finding announced in this document was made on February 9, 
2010.

ADDRESSES: This finding is available on the Internet at https://www.regulations.gov at Docket Number FWS-R6-ES-2009-0021. 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 Ecological Services Field Office, 2369 
W. Orton Circle, Suite 50, West Valley City, UT 84119. Please submit 
any new information, materials, comments, or questions concerning this 
finding to the above address.

FOR FURTHER INFORMATION CONTACT: Larry Crist, Field Supervisor, Utah 
Ecological Services Field Office (see ADDRESSES); by telephone at 801-
975-3330; or by facsimile at 801-975-3331. Persons who use a 
telecommunications device for the deaf (TDD) may 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 
indicating that listing the species may be warranted, we make a finding 
within 12 months of the date of receipt of the petition. In this 12-
month finding, we may determine that the petitioned action is either: 
(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 
threatened or endangered, 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 Actions

    On October 2, 2007, we received a petition dated October 1, 2007, 
from the Center for Biological Diversity (Center) requesting that the 
American pika (Ochotona princeps) be listed as threatened or endangered 
under the Act. Included in the petition was a request that we conduct a 
status review of each of the 36 recognized subspecies of American pikas 
to determine if separately listing any subspecies as threatened or 
endangered may be warranted. Specifically, the Center requested that 
seven American pika subspecies be listed as endangered: the Ruby 
Mountains pika (O. p. nevadensis), O. p. tutelata (no common name), the 
White Mountains pika (O. p. sheltoni), the gray-headed pika (O. p. 
schisticeps), the Taylor pika (O. p. taylori), the lava-bed pika (O. p. 
goldmani), and the Bighorn Mountain pika (O. p. obscura). The Center 
requested that the remaining subspecies be listed as threatened. We 
acknowledged receipt of the petition in a letter to the Center dated 
October 18, 2007. In that letter, we also stated that we could not 
address its petition at that time, because existing court orders and 
settlement agreements for other listing actions required nearly all of 
our listing funding. We also concluded that emergency listing of the 
American pika was not warranted at that time.
    We received a 60-day notice of intent to sue from the Center dated 
January 3, 2008. We received a complaint from the Center on August 19, 
2008. We submitted a settlement agreement to the Court on February 12, 
2009, agreeing to submit a 90-day finding to the Federal Register by 
May 1, 2009, and, if appropriate, to submit a 12-month finding to the 
Federal Register by February 1, 2010.
    We received a letter from the Center, dated November 3, 2008, that 
discussed and transmitted supplemental information found in recent 
scientific studies that had not been included in the original petition. 
We considered this additional information when making this finding.
    In our 90-day finding published on May 7, 2009 (74 FR 21301), we 
reviewed the petition, petition supplement, supporting information 
provided by the petitioner, and information in our files, and evaluated 
that information to determine whether the sources cited support the 
claims made in the petition. We found that the petitioner presented 
substantial information indicating that listing the American pika as 
threatened or endangered under the Act may be warranted, because of the 
present or threatened destruction, modification, or curtailment of its 
habitat or range as a result of effects related to global climate 
change. We also solicited additional data and information from the 
public, other governmental agencies, the scientific community, 
industry, and other interested parties concerning the status of the 
American pika throughout its range. The information collection period 
for submission of additional information ended on July 6, 2009. This 
notice constitutes our 12-month finding on the October 1, 2007, 
petition to list the American pika as threatened or endangered.

Species Information

Biology
    Like other pika species, the American pika (hereafter pika, unless 
stated otherwise) has an egg-shaped body with short legs, moderately 
large ears, and no visible tail (Smith and Weston 1990, p. 2). Fur 
color varies among subspecies and across seasons, typically with 
shorter, brownish fur in summer and longer, grayish fur in winter 
(Smith and Weston 1990, p. 3). The species is intermediately sized, 
with adult body lengths ranging from 162 to 216 millimeters (6.3 to 8.5 
inches) and mean body mass ranging from 121 to 176

[[Page 6439]]

grams (4.3 to 6.2 ounces) (Hall 1981, p. 287; Smith and Weston 1990, p. 
2).
    American pikas are generalist herbivores that select different 
classes of vegetation (Huntley et al. 1986, p. 143) and use different 
parts of the same plants when grazing versus haying (Dearing 1997a, p. 
1160). Feeding (the immediate consumption of vegetation) occurs year-
round; haying (the storage of vegetation for later consumption) and the 
creation of haypiles occurs only in summer months after the breeding 
season (Smith and Weston 1990, p. 4). The primary purpose of haypiles 
is overwintering sustenance, and individuals harvest more vegetation 
than necessary for these haypiles (Dearing 1997a, p. 1156). Pikas feed 
an average distance of 2 meters (m) (6.5 feet (ft)) from talus and will 
travel an average distance of 7 m (23 ft) when haying (Huntly et al. 
1986, pp. 141-142). Huntly et al. (1986, p. 142) found that no feeding 
occurred beyond 10 m (33 ft) from talus, but haying was observed up to 
30 m (98 ft).
    Vegetative communities immediately adjacent to pika locations are 
typically dominated by grasses (Huntly 1987, p. 275). When pikas are 
excluded from grazing near talus slopes, the biomass of forbs and 
sedges (Roach et al. 2001, p. 319) and cushion plants (Huntly 1987, p. 
275) increases rapidly. Therefore, foraging pikas influence the 
presence of specific plant classes or functional groups, vegetative 
cover, and species richness (Huntly 1987, p. 274; Roach et al. 2001, p. 
315), and modify habitat in their quest for food and survival (Aho et 
al. 1998, p. 405). Forbs and woody plants are typically found in pika 
haypiles (Huntly et al. 1986, p. 143), which provide the major source 
of sustenance for the winter (Dearing 1997a, p. 1156). High phenolic 
(chemical compounds characterized by high acidity) concentrations of 
forbs and shrubs prevent pikas from grazing immediately on these plant 
types; however, pikas cache these plants and delay consumption until 
the toxins decay to tolerable levels (Dearing 1997b, p. 774). 
Additionally, plants with high levels of the phenolics deter bacterial 
growth and exhibit superior preservation qualities (Dearing 1997b, p. 
774).
    Thermoregulation is an important aspect of American pika 
physiology, because individuals have a high normal body temperature of 
approximately 40 [deg]C (104 [deg]F) (MacArthur and Wang 1973, p. 11; 
Smith and Weston 1990, p. 3), and a relatively low lethal maximum body 
temperature threshold of approximately 43 [deg]C (109.4 [deg]F) (Smith 
and Weston 1990, p. 3). Most thermoregulation of individuals is 
behavioral, not physiological (Smith 1974b, p. 1372; Smith and Weston 
1990, p. 3). In warmer environments, such as during midday sun and at 
lower elevation limits, pikas typically become inactive and withdraw 
into cooler talus openings (Smith 1974b, p. 1372; Smith and Weston 
1990, p. 3). Below-surface temperatures within talus openings can be as 
much as 24 [deg]C (43.2 [deg]F) cooler than surface temperatures during 
the hottest time of day (Finn 2009a, pers. comm.). Pikas avoid 
hyperthermia (heat stroke) during summer months by engaging in short 
bursts of surface activity followed by retreat to a cooler microclimate 
beneath the surface (MacArthur and Wang 1974, p. 357). Pikas can be 
nocturnal where daytime temperatures are stressful and restrict diurnal 
activity (Smith 1974b, p. 1371).
    Habitat occupied by American pikas is often patchily distributed, 
leading to a local population structure that is composed of island-like 
sites commonly termed a metapopulation (Smith and Weston 1990, p. 4; 
Moilanen et al. 1998, pp. 531-532). A metapopulation is composed of 
many largely discrete local populations, and metapopulation dynamics 
are characterized by extinction and recolonization occurring within 
independent local populations (Hanski 1999, cited in Meredith 2002, p. 
47). Local populations that make up each metapopulation frequently 
become extirpated and can be subsequently reestablished by immigration 
(Smith 1974a, p. 1112; Moilanen et al. 1998, p. 532). American pikas 
within metapopulations often exhibit a low emigration rate, especially 
in adults. Juveniles usually have short migration distances; however, 
exceptions occur (Peacock 1997, pp. 346-348).
    Dynamics of American pika populations are sufficiently asynchronous 
(not occurring at the same time), so that simultaneous extinction of 
entire metapopulations is unlikely (Smith 1980, p. 11; Moilanen et al. 
1998, p. 532). When a single population becomes extirpated, distance to 
a source of colonizing pikas is an influential factor determining the 
probability of recolonization (Smith 1980, p. 11). American pika 
populations on small and medium-sized islands are more likely to be 
extirpated, with the probability of extirpation being higher on more 
distant islands (Smith 1980, p. 12).
    Historically, researchers hypothesized that American pika juveniles 
are philopatric (remain in or return to their birthplace), dispersing 
only if no territory is available within their birth place (various 
studies cited in Smith and Weston 1990, p. 6). However, Peacock (1997, 
pp. 346-348) demonstrated that juvenile emigration to other population 
sites occurred over both long (2 kilometers (km); 1.24 miles (mi)) and 
short distances, and acted to support population stability by replacing 
deceased adults. Territory availability is a key factor for dispersal 
patterns, and local pika populations lack clusters of highly related 
individuals (Peacock 1997, pp. 347-348).
    Dispersal by American pikas is governed by physical limitations. 
Smith (1974a, p. 1116) suggested that it was difficult for juveniles to 
disperse over distances greater than 300 m (984 ft) in low-elevation 
(2,500 m (8,200 ft)) populations. Lower elevations are warmer in summer 
and represent the lower edge of the elevational range of the species 
(Smith 1974a, p. 1112). While dispersal distances of 3 km (1.9 mi) have 
been documented at other locations and elevational ranges (Hafner and 
Sullivan 1995, p. 312), it is believed that the maximum individual 
dispersal distance is probably between 10 and 20 km (6.2 and 12.4 mi) 
(Hafner and Sullivan 1995, p. 312). This conclusion is based on genetic 
(Hafner and Sullivan 1995, pp. 302-321) and biogeographical (Hafner 
1994, pp. 375-382) analysis. Genetic analysis revealed that pika 
metapopulations are separated by between 10 and 100 km (6.2 to 62 mi) 
(Hafner and Sullivan 1995, p. 312). Biogeographical analysis 
demonstrated that, during the warmer period of the mid-Holocene (about 
6,500 years ago), the species retreated to cooler sites, and the 
species subsequently expanded its range somewhat as climatic conditions 
cooled (Hafner 1994, p. 381). However, the species has not recolonized 
vacant habitat patches greater than 20 km (12.4 mi) from refugia sites 
and has recolonized less than 7.8 percent of available patches within 
20 km (12.4 mi) of those same refugia sites (Hafner 1994, p. 381). The 
lack of recolonization is due to habitat becoming unsuitable from 
vegetation filling in talus areas (removing pika habitat) or from 
habitat becoming too dry due to environmental changes resulting from 
historical changes in climate (Hafner 1994, p. 381).
    Individual pikas are territorial, maintaining a defended territory 
of 410 to 709 square meters (m\2\) (4,413 to 7,631 square feet 
(ft\2\)), but fully using overlapping home ranges of 861 to 2,182 m\2\ 
(9,268 to 23,486 ft\2\) (various studies cited in Smith and Weston 
1990, p. 5). Individuals mark their territories with scent and defend 
the territories through

[[Page 6440]]

aggressive fights and chases (Smith and Weston 1990, p. 5).
    Adults with adjacent territories form monogamous mating pairs. 
Males are sexually monogamous, but make little investment in rearing 
offspring (Smith and Weston 1990, pp. 5-6). Females give birth to 
average litter sizes of 2.4 to 3.7 twice a year (Smith and Weston 1990, 
p. 4). However, fewer than 10 percent of weaned juveniles originate 
from the second litter, because mothers only wean the second litter if 
the first litter is lost (various studies cited in Smith and Weston 
1990, p. 4).
    Adult pikas can be territorially aggressive to juveniles, and 
parents can become aggressive to their own offspring within 3 to 4 
weeks after birth (Smith and Weston 1990, p. 4). To survive the winter, 
juveniles need to establish their own territories and create haypiles 
before the winter snowpack (Smith and Weston 1990, p. 6; Peacock 1997, 
p. 348). However, establishing a territory and building a haypile does 
not ensure survival.
    Yearly average mortality in pika populations is between 37 and 53 
percent. Few pikas live to be 4 years of age (Peacock 1997, p. 346), 
however, some individuals survive up to 7 years (Smith 2009, p. 2).
Taxonomy
    Historically, many taxonomic forms have been identified within 
Nearctic pikas, including as many as 13 species and 37 subspecies 
(Hafner and Smith 2009, p. 1). Initially, 13 species and 25 subspecies 
of Nearctic (a biogeographic region that includes the Arctic and 
temperate areas of North America and Greenland) pikas were described 
(Richardson 1828, cited in Hafner and Smith 2009). Howell (1924, pp. 
10-11) performed a full taxonomic revision of the American pika and 
recognized 3 species: Ochotona collaris, Ochotona princeps (16 
subspecies), and Ochotona schisticeps (9 subspecies). Later, Hall 
(1981, pp. 286-292) described 36 subspecies of American pika spread 
throughout western Canada and the western United States. The petition 
(Wolf et al. 2007) from the Center of Biological Diversity that 
requested that all American pika subspecies be listed as threatened or 
endangered was based on the Hall (1981, pp. 286-292) taxonomy.
    These references, in addition to others (Hafner and Smith 2009, p. 
5) were used as the set of authoritative resources on pika taxonomy 
until genetic work identified four major genetic units of the American 
pika in the northern Rocky Mountains, Sierra Nevada, southern Rocky 
Mountains, and Cascade Range (Hafner and Sullivan 1995, p. 308). 
Further molecular phylogenetic and morphometric studies indicate the 
existence of five cohesive genetic units that have been referred to as 
``distinct evolutionarily significant units'' (Galbreath et al. 2009a, 
p. 17; Galbreath et al. 2009b, pp. 7, 52). These studies support a 
revision of the subspecific taxonomy of the American pika to include 
five recognized subspecies: Ochotona princeps princeps (Northern 
Rockies), O. p. saxatilis (Southern Rockies), O. p. fenisex (Coast 
Mountains and Cascade Range), O. p. schisticeps (Sierra Nevada and 
Great Basin), and O. p. uinta (Uinta Mountains and Wasatch Range of 
Central Utah) (Hafner and Smith 2009, pp. 16-25). The previously 
described 36 subspecies (Hall 1981, pp. 286-292) are now referred to as 
subspecies synonyms, with each subspecies synonym corresponding to a 
subspecies described by Hafner and Smith (2009, pp. 16-25). We are 
making our finding based on the most recent information that has 
identified five subspecies of American pika. The petition (Wolf et al. 
2007) from the Center of Biological Diversity no longer contains the 
best available information on taxonomy.
Historic Distribution and Habitat
    The restriction of American pikas to their current distribution 
(discussed below) is relatively recent. The shift in habitat range was 
shaped by long-term climate change and attendant impacts on vegetation.
    The geographic distribution of American pika may have encompassed 
not only the western United States and Canada during the last glacial 
maximum (30,000 years ago or later), but also parts of the eastern 
United States (Grayson 2005, p. 2104). Archaeological and 
paleontological records for pika demonstrate that approximately 12,000 
years ago, pikas were living at relatively low elevations (less than 
2,000 m (6,560 ft)) in areas devoid of talus (Mead 1987, p. 169; 
Grayson 2005, p. 2104). By the Wisconsinan glacial period 
(approximately 40,000 to 10,000 years ago), American pikas were 
restricted to the intermontane region of the western United States and 
Canada.
    Low-elevation populations of American pikas became extinct in the 
northern half of the Great Basin between 7,000 and 5,000 years ago 
(Grayson 1987, p. 370). Fossil records indicate that the species 
inhabited sites farther south and at lower elevations than the current 
distribution during the late Wisconsinan and early Holocene periods 
(approximately 40,000 to 7,500 years ago), but warming and drying 
climatic trends in the middle Holocene period (approximately 7,500 to 
4,500 years ago) forced populations into the current distribution of 
montane refugia (Grayson 2005, p. 2103; Smith and Weston 1990, p. 2). 
During the late Wisconsinan and early Holocene, now-extirpated American 
pika populations in the Great Basin occurred at an average elevation of 
1,750 m (5,740 ft), which is 783 m (2,569 ft) lower than 18 extant (in 
existence) Great Basin pika populations (Grayson 2005, p. 2106).
Current Distribution and Habitat
    Ochotona princeps princeps is patchily distributed in cool, rocky 
habitat, primarily in high-elevation alpine habitats (see below for 
exceptions), from the Northern Rocky Mountains of central British 
Columbia and Alberta through Idaho and Montana, several mountain ranges 
of Wyoming, the Ruby Mountains of Nevada, the Wasatch Range of Idaho 
and Utah, and the Park Range and Front Range of Colorado north of the 
Colorado River (Hafner and Smith 2009, p.19). O. p. saxatilis occupies 
habitat in the southern Rocky Mountains south of the Colorado River 
(Front Range, San Juan Mountains, Sangre de Cristo Range), and isolated 
highlands including the La Sal Mountains of southeastern Utah, Grand 
Mesa of Colorado, and Jemez Mountains of New Mexico (Hafner and Smith 
2009, pp. 21-22). O. p. schisticeps occupies habitats in volcanic peaks 
of northern California, throughout the Sierra Nevada of California and 
Nevada, and isolated highlands throughout the Great Basin of Nevada, 
eastern Oregon (north to the Blue Mountains), and southwestern Utah 
(Hafner and Smith 2009, pp. 23-24). O. p. fenisex occupies habitats 
from the Coast Mountains and Cascade Range from central British 
Columbia south to southern Oregon (Hafner and Smith 2009, p. 20). O. p. 
uinta is patchily distributed in habitats in the Uinta Mountains and 
Wasatch Range of central Utah (Hafner and Smith 2009, p. 24).
    Temperature restrictions influence the species' distribution 
because hyperthermia or death can occur after brief exposures (as 
little as 6 hours) to ambient temperatures greater than 25.5 [deg]C 
(77.9 [deg]F), if individuals cannot seek refuge from heat stress 
(Smith 1974b, p. 1372). Therefore, American pika habitat progressively 
increases in elevation in the southern extent of the distribution 
(Smith and Weston 1990, p. 2). In the northern part of its distribution 
(southwestern Canada), populations occur from sea level to 3,000 m 
(9,842 ft), but in the southern extent (New Mexico, Nevada, and

[[Page 6441]]

southern California) populations rarely exist below 2,500 m (8,202 ft) 
(Smith and Weston 1990, p. 2). Some exceptions exist in the southern 
portion of the species' range. For example, pikas in 10 percent of 420 
study sites in the Sierra Nevada Mountains, Great Basin, and Oregon 
Cascade Mountains occur below 2,500 m and as low as 1,645 m (5,396 ft) 
at McKenzie Pass in the Cascade Mountains of Oregon (Millar and 
Westfall 2009, p. 16). Beever et al. (2008, p. 10) recently discovered 
a new population of American pika in the Hays Canyon Range of 
northwestern Nevada at elevations ranging from 1,914 to 2,136 m (6,280 
to 7,008 ft).
    American pikas primarily inhabit talus fields fringed by suitable 
vegetation in alpine or subalpine areas (Smith and Weston 1990, pp. 2-
4). A generalist herbivore that does not hibernate, the species relies 
on haypiles of summer vegetation stored within talus openings to 
persist throughout the winter months (Smith and Weston 1990, p. 3). 
Alpine meadows that provide forage are important to pika survival in 
montane environments. The species also occupies other habitats that 
include volcanic land features (Beever 2002, p. 26; Millar and Westfall 
2009, p. 10) and anthropogenic settings such as mine tailings, piles of 
lumber, stone walls, rockwork dams, and historic foundations (Smith 
1974a, p. 1112; Smith 1974b, p. 1369; Lutton 1975, p. 231; Crisafulli 
2009, pers. comm.; Millar and Westfall 2009, p. 10).
    Pikas use talus, which can include rock-ice features, and other 
habitat types for den sites, food storage, and nesting (Smith and 
Weston 1990, p. 4; Beever et al. 2003, p. 39). Rock-ice features are 
defined as glacial- or periglacial- (i.e., around or near glaciers) 
derived landforms in high-elevation, semi-arid temperature mountain 
ranges and arctic landscapes (Millar and Westfall 2008, pp. 90-91). 
Talus, rock-ice feature till, and volcanic features (described below) 
also provide microclimate conditions suitable for pika survival by 
creating cooler, moist refugia in summer months (Beever 2002, p. 27; 
Millar and Westfall 2009, p. 19-21) and insulating individuals in the 
colder winter months (Smith 1978, p. 137; Millar and Westfall 2009, p. 
21).
    Among 420 sites surveyed by Millar and Westfall (2009, p. 10), 83 
percent of the pika sites occurred in rock-ice feature till, most 
notably rock-glacier and boulder-stream landforms, which contain 
topographic-climatic conditions that are favored by pikas (Millar and 
Westfall 2009, p. 20).
    Pikas also inhabit more atypical habitats that include lava tubes, 
caves, valley trenches, fault scarps, fault cracks, and cliff faces, 
which provide suitable habitat and thermal refuge (Beever 2002, pp. 26, 
28; Millar and Westfall 2009, p. 10). For example, in Lava Beds 
National Monument in northern California and Craters of the Moon 
National Monument in southern Idaho, pikas typically inhabit large, 
contiguous areas of volcanic habitat (Beever 2002, p. 28). Within this 
habitat type, forage vegetation is accessible within distances 
comparable to dimensions of home ranges (Beever 2002, p. 28). Pikas 
select habitat that includes topographical features characterized by 
rocks large enough to provide necessary interstitial spaces for 
underground movement and tunneling. Like talus and rock-ice features, 
these habitats provide pikas with cool refugia during conditions that 
may result in heat stress, which in addition to behavioral 
thermoregulation mechanisms, allow pika to persist in these low-
elevation and potentially thermally challenging environments (Beever 
2002, pp. 27-28).
Population Status
    We relied on information from the International Union for 
Conservation and Nature of Natural Resources (IUCN), NatureServe, 
published literature, and public submissions during the information 
collection period on our 90-day finding to evaluate the status of 
American pika populations.
    The IUCN Red List of Threatened Species provides taxonomic, 
conservation status, and distribution information on plants and animals 
(IUCN 2009, p. 2). The IUCN Red List system is designed to determine 
the relative risk of extinction for species, and to catalogue and 
highlight plant and animal species that are facing a higher risk of 
global extinction. The IUCN identified the status of the American pika 
species as Least Concern in 2008 under the Red List review process 
(Beever and Smith 2008, p. 3). According to IUCN (version 3.1): ``a 
taxon is Least Concern when it has been evaluated against the criteria 
and does not qualify for Critically Endangered, Endangered, Vulnerable 
or Near Threatened. Widespread and abundant taxa are included in this 
category.'' The IUCN uses five quantitative criteria to determine 
whether a taxon is threatened or not, and if threatened, which category 
of threat it belongs in (i.e., critically endangered, endangered, or 
vulnerable). ``To list a particular taxon in any of the categories of 
threat, only one of the criteria needs to be met. The five criteria 
are: (1) Declining population (past, present and/or projected); (2) 
Geographic range size, and fragmentation, decline or fluctuations; (3) 
Small population size and fragmentation, decline, or fluctuations; (4) 
Very small population or very restricted distribution; and (5) 
Quantitative analysis of extinction risk (e.g., Population Viability 
Analysis) (IUCN Standards and Petitions Working Group 2008, p. 11).''
    However, the IUCN (using the Hall (1981) taxonomic classification, 
as Vulnerable or Near Threatened) considers eight American pika 
subspecies synonyms. These subspecies synonyms are Ochotona princeps 
goldmani, O. p. lasalensis, O. p nevadensis, O. p. nigrescens, O. p. 
obscura, O. p. sheltoni, O. p. tutelata, and O. p. schisticeps (Beever 
and Smith 2008, p. 3). A vulnerable species or subspecies is facing a 
high risk of extinction in the wild. A near threatened species or 
subspecies is close to qualifying as or is likely to qualify as 
vulnerable in the near future (IUCN, section 3.1). Status for the eight 
subspecies synonyms applies under the Hall (1981) taxonomic 
classification of the American pika but may not apply to any of the 
subspecies described by Hafner and Smith (2009, pp. 16-25). For 
example, a status of ``vulnerable'' for O. p. goldmani does not imply 
that O. p. princeps (described by Hafner and Smith 2009, pp. 17-20) is 
vulnerable as well because the range of O. p. goldmani does not 
constitute the entire range of O. p. princeps.
    NatureServe is a nonprofit organization that, in part, collects and 
manages species information and data in an effort to increase our 
understanding of species, ecosystems, and conservation issues 
(NatureServe 2009a, p. 1). NatureServe also assesses available 
scientific information to determine species status based on factors, 
including population number and size, trends, and threats. NatureServe 
provides comprehensive reports for species, including American pika. 
The report (Nature Service 2009b, pp. 1-7) for the American pika 
includes taxonomic information, conservation status information, lists 
of natural heritage records, species distribution by watershed, ecology 
and life history information, population delineation, population 
viability, and references. The report does not contain information on 
threats or a justification for designation of conservation status 
within states and provinces.
    In a review conducted in 1996, NatureServe assigned the American 
pika a global status of secure (i.e., common; widespread and abundant) 
in the United States and the Canadian provinces of

[[Page 6442]]

Alberta and British and Columbia (NatureServe 2009b, pp. 1-2; Quinlan 
2009, pers. comm.). Within the United States, NatureServe considers the 
species secure or apparently secure (i.e., uncommon but not rare; some 
cause for long-term concern due to declines or other factors) in 
Colorado, Idaho, Montana, Oregon, Washington, and Wyoming. NatureServe 
assigned the American pika a status of vulnerable in California and 
Utah (i.e., vulnerable in the jurisdiction due to a restricted range, 
relatively few populations, recent and widespread declines, or other 
factors making it vulnerable to extirpation), and a status of imperiled 
in Nevada and New Mexico (i.e., imperiled in the jurisdiction, because 
of rarity due to very restricted range, very few populations, steep 
declines, or other factors making it very vulnerable to extirpation 
from the jurisdiction).
Northern Rocky Mountain Subspecies (Ochotona princeps princeps)
    The Northern Rocky Mountains subspecies (Ochotona princeps 
princeps) occurs primarily in Canada, Montana, Idaho, and Wyoming, with 
a smaller amount of occupied habitat in Washington, Nevada, Utah, and 
Colorado. Data on status and trends of O. p. princeps are lacking for 
portions of the subspecies range. Available data consists mostly of a 
list of sites verified to be occupied in recent surveys. In locations 
where pika surveys have been conducted, we do not have historical 
information of the subspecies' at those sites for comparison.
    The Canadian Endangered Species Conservation Council (2005) 
assigned a ranking of secure to Ochotona princeps princeps in Alberta 
and British Columbia, which are the only two provinces where this 
subspecies occurs in Canada. The ranking is based upon occurrence of 
large numbers of pikas in secure habitat (British Columbia Conservation 
Data Centre 2009, p. 1; Court 2009, pers. comm.). Pikas are common in 
suitable habitat in the mountains on both provincial lands and in 
national parks (Court 2009, pers. comm.). The population is thought to 
be stable in Alberta, Canada (Court 2009, pers. comm.). Greater than 
100 occurrences of O. p. princeps occur within Alberta (Court 2009, 
pers. comm.). We do not have population trend information for British 
Columbia. We do not have any information to suggest the distribution of 
the pika is changing in Canada.
    In Montana, there is little historical information to assess 
whether habitat loss has occurred or if populations are stable. Limited 
available data does not indicate a decline. Approximately 90 percent of 
available habitat in Glacier National Park is occupied (National Park 
Service (NPS) 2009, p. 9). Based upon occupancy rates elsewhere (Utah 
Division of Wildlife Resources (UDWR) 2009, pp. 6, 11), we conclude the 
occupancy rate of pikas within Glacier National Park is high.
    Limited data are available for pika distribution, abundance, and 
population status in Wyoming. American pikas occur in every Wyoming 
mountain range except Laramie, Wasatch, and Black Hills (Wyoming Game 
and Fish Department (WGFD) 2009, p. 1). American pikas are believed to 
occur in all locations where they were observed historically within the 
Grand Teton National Park (NPS 2009, p. 10). The WGFD will add the 
American pika to their 2010 State Wildlife Action Plan (WAP) (WGFD 
2009, p. 1). They propose to treat the subspecies as having an Unknown 
Native Species Status because population and distribution trends are 
unknown and limiting factors are poorly understood (WGFD 2009, p. 1).
    In Idaho, the subspecies is broadly distributed and occupies a 
substantial number of sites throughout much of the State (Idaho 
Department of Fish and Game (IDFG) 2009, p. 1). The IDFG has no 
information to suggest threats exist to the subspecies. Pikas are not 
identified as a Species of Greatest Conservation Need in the Idaho 
Comprehensive Wildlife Conservation Strategy (CWCS) and pikas are 
considered to be secure, common, and widespread based on NatureServe's 
conservation status (IDFG 2005, App. A, p. 18). O. p. princeps was 
studied at Craters of the Moon National Monument in Idaho (Beever 2002, 
p. 25; NPS 2009, pp. 2-3), but reports did not reveal any information 
related to the status of pika populations there.
    Ochotona princeps princeps in Utah currently have a high occupancy 
rate (96 percent) in suitable habitat (UDWR 2009, p. 7). Although there 
is no historical population information, UDWR believes that the high 
occupancy rate reflects stable populations (UDWR 2009, p. 11).
    In Colorado, Ochotona princeps princeps is found only in the 
northern part of the State. Colorado Division of Wildlife (CDOW) (2009, 
p. 19) documented greater than 40 occupied sites based on historic and 
recent site surveys. Reports on O. p. princeps in Colorado do not 
provide any information on status (NPS 2009, p. 10-12; Ray 2009, pp. 1-
4).
    Nevada and Washington have little information on the subspecies 
status. American pika records collected from 1969 to 2008 from the Ruby 
Mountain chain in northeast Nevada identify at least 33 pika locations 
(Nevada Department of Wildlife (NDOW) 2009, pp. 2-3); however, we have 
no information on the status of populations from those locations. We 
have no information on the status of O. p. princeps in Washington.
    As previously stated, Beever and Smith (2008, p. 3) considered 
populations of O. p. goldmani, O. p. nevadensis, and O. p obscura, 
which represent a portion of the range of O. p. princeps (Hafner and 
Smith 2009, pp. 18-19), as vulnerable (i.e., facing a high risk of 
extinction in the wild). Additionally, NatureServe (2009, p. 2) 
assigned Utah pikas, which contains populations representing all 
subspecies except O. p. fenisex, a status of vulnerable (i.e., a 
restricted range, relatively few populations, recent and widespread 
declines, or other factors making it vulnerable to extirpation).
    In summary, most States and provinces that contain populations of 
O. p. princeps have not determined the subspecies' status and do not 
have information on population trends. Some populations within central 
Idaho (O. p. goldmani), northwestern Nevada (O. p. nevadensis), north-
central Wyoming (O. p. obscura), and north-central Utah may be 
vulnerable (Beever and Smith 2008, p. 3; NatureServe 2009, p. 2). 
Outside of these areas, we do not have adequate information to 
determine the status of O. p. princeps populations.
Sierra Nevada Subspecies (Ochotona princeps schisticeps)
    The Sierra Nevada subspecies (Ochotona princeps schisticeps) occurs 
primarily in California, Nevada, and Oregon with a small portion of 
occupied habitat in Utah. This subspecies has received more scientific 
study than any other American pika subspecies (Grayson 2005, p. 2104). 
Pikas are designated as a vulnerable species as well as a species of 
conservation priority in Nevada's WAP, with a declining population (WAP 
Team 2006, pp. 291, 405). O. p. schisticeps status appears to be 
declining within the interior Great Basin, primarily in southern Oregon 
and northwestern Nevada, and some places along the eastern Sierra 
Nevada Mountain Range (Beever et al. 2003, p. 44; Wilkening 2007, p. 
58); however, outside of these areas there is no indication that the 
subspecies is in decline (Millar and Westfall 2009, p. 25). As 
identified by Beever et al. (2003, pp. 39, 44), the interior Great 
Basin refers to the hydrographic definition of the Great Basin (Grayson 
1993, cited in Beever et al. 2003, p. 39).

[[Page 6443]]

    As previously mentioned, some isolated populations of O. p. 
schisticeps have been extirpated in the interior Great Basin. Beever et 
al. (2003, p. 43) did not detect pikas at 6 of 25 historical (dating 
back to the early to mid-1900s) populations during surveys from 1994 to 
1999 and later documented three extirpations during 2000 to 2007 
(Wilkening 2007, pp. 25-27; Beever et al. 2009, p. 15).
    Researchers have not systematically searched all potential pika 
habitat within the Great Basin and acknowledge that other sites with 
pikas may exist (Beever et al. 2009, pp. 31), particularly the Toiyabe 
Mountain Range, White Mountains, Toquima Mountain Range, and the Warner 
Mountains (Meredith 2002, p. 11; Beever 2009a, pers. comm.). In fact, 
two new sites were discovered in the Great Basin in northwestern Nevada 
from 2008 to 2009: Hays Canyon (Beever et al. 2008, p. 9) and Sheldon-
Hart National Wildlife Refuge (Collins 2009, pers. comm.). However, the 
subspecies is rare in the Great Basin, and likely has been relatively 
rare in the Great Basin for the past several thousand years. It is 
unlikely that many additional occupied sites will be found (Beever et 
al. 2008, p. 11).
    Trends of pika status are mixed in other locations within the 
subspecies range. Pikas occur within Sequoia and Kings Canyon National 
Parks in California along the eastern edge of the Sierra Nevada 
Mountain Range, however, the population status is unknown (NPS 2009, p. 
6). Pikas are widely distributed throughout Lava Beds National Monument 
(Ray and Beever 2007, p. 2) and populations appear to persist in warmer 
and drier sites, which is contrary to expectations because pikas are 
generally restricted to cool, moist habitats on higher peaks (Hafner 
1993, p. 375). The lower elevation range limit of pikas in Yosemite 
National Park has contracted and moved upslope by 153 m (502 ft) 
(Moritz et al. 2008, p. 263), and at least one historic pika site has 
been extirpated within the Park (Moritz 2007, p. 37). Despite this 
extirpation, we do not know the status of the entire Yosemite National 
Park pika population. Pika populations near Bodie, California, have 
experienced decline as well, but not in the largest portion of the 
population which contains more suitable habitat and subsequently more 
pikas (Moilanen et al. 1998, p. 531; Nichols 2009, pp. 2, 5; Smith 
2009, pers. comm.).
    The relative number of unoccupied sites increased from the Sierra 
Nevada eastward into the Great Basin ranges (Millar and Westfall 2009, 
pp. 9, 11). Millar and Westfall (2009, p. 25) concluded that pika 
populations in the Sierra Nevada and southwestern Great Basin are 
thriving and show little evidence of extirpation or decline. Central 
Great Basin populations, on the other hand, appear less viable and more 
subject to disturbance from random events (Millar and Westfall 2009, p. 
25).
    In Utah, a population of pikas at Cedar Breaks National Monument 
was extirpated sometime between 1974 and 2006 (Oliver 2007, p. 5). As 
of 2009, the site still does not contain pikas (NPS 2009, p. 9). Pikas 
may have disappeared from sites near Lava Point in Zion National Park 
(NPS 2009, p. 13; Oliver 2007, pp. 7-8). However, pikas occur in other 
nearby locations (NPS 2009, p. 9; UDWR 2009, p. 20), demonstrating that 
suitable habitat capable of supporting a pika population still exists 
in southern Utah. Eighty-four percent of Ochotona princeps schisticeps 
suitable habitats in Utah are occupied (UDWR 2009, p. 7).
    In summary, despite some of the uncertainty in trends across the 
current range of O. p. schisticeps populations, it is clear that some 
interior Great Basin pika populations (Beever et al. 2003, pp. 44, 53-
54; Beever et al. 2009, p. 6) are being extirpated and moving upslope 
in elevation. The recent loss of low-elevation historical pika 
populations near the southern edge of historical range within the Great 
Basin appears to track the fossil record (see section on Historic 
Distribution and Habitat). The recent rate of population loss is more 
rapid than that suggested by paleontological records (Beever et al. 
2003, p. 48). The majority of suitable habitat for O. p. schisticeps 
occurs outside of the Great Basin in the Sierra Nevada Mountain Range 
and a large study area in the Sierra Nevada Mountain Range shows the 
status appears to be stable.
Southern Rocky Mountain Subspecies (Ochotona princeps saxatilis)
    Even in the absence of survey data for portions of the range of the 
Southern Rocky Mountain subspecies, Ochotona princeps saxatilis, 
available information suggests that the subspecies is stable across the 
majority of its range. Survey data are lacking for portions of the 
subspecies' range.
    Pikas are well distributed in high-elevation areas of Colorado, 
which contains the majority of the subspecies' habitat. Fifty-eight of 
62 historical sites surveyed had O. p. saxatilis populations persisting 
even at relatively low-elevation 2,743 to 3,048 m (9,000 to 10,000 ft) 
sites (CDOW 2009, p. 22; Peterson 2009, pers. comm.). Pika habitat is 
extensive in Colorado, and connectivity between pika habitat and 
populations appears sufficient to maintain a healthy population 
structure (CDOW 2009, p. 22).
    In Utah, 92 percent of surveyed suitable pika habitat in the La Sal 
Mountains of eastern Utah was occupied (UDWR 2009, p. 7). There is no 
evidence of declines of American pika populations from historical 
levels in Utah (UDWR 2009, p. 11).
    Density and trend data are not available for Ochotona princeps 
saxatilis populations in New Mexico (New Mexico Department of Game and 
Fish (NMDGF) 2009, p. 2; U.S. Forest Service (USFS) 2009, p. 1). New 
Mexico's CWCS lists the Goat Peak pika (was Ochotona princeps 
nigrescens, now included in O. p. saxatilis) as a subspecies of 
greatest conservation need as well as vulnerable and State sensitive 
(NMDGF 2006, pp. 55, 57). However, based on limited field observation, 
persistence of O. p saxatilis populations within New Mexico does not 
appear to reflect the pattern of recent extirpation observed within the 
interior Great Basin (NMDGF 2009, p. 3). Beever and Smith (2008, p. 3) 
have assigned O. p. lasalensis and O. p. nigrescens, which now belong 
to the O. p. saxatilis subspecies (see Table 1; Hafner and Smith 2009, 
p. 21), a status of vulnerable.
    Despite some of the uncertainty in status across the range of O. p. 
saxatilis in New Mexico, the subspecies appears to be well distributed 
throughout the available habitat, especially in Colorado and Utah (CDOW 
2009, p. 22; UDWR 2009, p. 11). There is no evidence indicating that 
the subspecies is in decline across its range in Utah and Colorado. 
Based on other status reviews (Beever and Smith 2008; NatureServe 
2009b, p. 2), further monitoring may be warranted for O. p. saxatilis 
populations in the Jemez Mountains of New Mexico and La Sal Mountains 
of Utah to obtain a current status characterization of this portion of 
the subspecies range.
Cascade Mountain Subspecies (Ochotona princeps fenisex)
    We have no trend data available for Ochotona princeps fenisex 
populations. In many locations where recent pika surveys have been 
conducted, no historical information exists for purposes of comparison. 
NatureServe has assigned the American pika a status of apparently 
secure (i.e., uncommon but not rare; some cause for long-term concern 
due to declines or other factors) in Oregon; secure (i.e., common; 
widespread and abundant) in the State of Washington; and secure in the 
Canadian province of British Columbia.

[[Page 6444]]

    All eight survey locations in the Three Sisters Mountains and at 
McKenzie Pass, (located in the Cascade Mountain Range) have evidence of 
recent pika activity (Millar and Westfall 2009, p. 9). O. p. fenisex 
populations also occur in low-elevation (range of 121 to 255 m (397 to 
837 ft)) habitat in the Columbia River Gorge, Oregon (Simpson 2009, p. 
244). We have population estimates of O. p. fenisex from Mt. St. Helens 
from 1992 to 1994 (Bevers 1998, p. 42), but no information on the 
population status.
    Survey data are lacking for a large portion of O. p. fenisex range, 
and no reports indicate population status. Based on the current pattern 
of known occupancy and the NatureServe (2009b, pp. 1-2) assessment, the 
subspecies is apparently secure.
Uinta Mountain Subspecies (Ochotona princeps uinta)
    The Uinta Mountain subspecies, Ochotona princeps uinta, occurs 
solely within the State of Utah. The species is believed to have a 
relatively high occupancy rate (63 percent) with no evidence of 
declines from historical levels (UDWR 2009, pp. 7, 9, 11, 20). Based on 
available information, O. p. uinta populations appear stable.
Summary of American Pika Population Status
    Most States and provinces that contain populations of O. p. 
princeps and O. p. fenisex have not determined the subspecies' status 
and do not have information on population trends. Information presented 
above suggests that O. p. schisticeps populations in some areas, 
primarily in the interior Great Basin, may be in decline. O. p. 
saxatilis populations appear to be well distributed throughout the 
majority of available habitat and O. p. uinta populations appear 
stable. Recent observed trends for O. p. princeps, O. p. saxatilis, O. 
p. fenisex, and O. p. uinta subspecies do not seem to mirror the loss 
of occupied pika sites and upward range contraction that has been 
reported for interior Great Basin populations. There is discrepancy 
among reported population trends within California, southern Utah, and 
New Mexico. Some information suggests that the species is vulnerable 
within some areas of California, southern Utah, and New Mexico (Beever 
and Smith 2008; NatureServe 2009b); however, other reports discussed 
above suggest that the O. p. schisticeps subspecies is stable or not in 
decline (Millar and Westfall 2009, p. 25; NMDGF 2009, p. 3; UDWR 2009, 
p. 11).

Summary of Information Pertaining to the Five Factors

    Section 4 of the Act and implementing regulations (50 CFR part 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: (1) The present or threatened destruction, modification, 
or curtailment of its habitat or range; (2) overutilization for 
commercial, recreational, scientific, or educational purposes; (3) 
disease or predation; (4) the inadequacy of existing regulatory 
mechanisms; or (5) other natural or manmade factors affecting its 
continued existence. In making this finding, information pertaining to 
the American pika 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 a petition to list the American pika or any of the five subspecies 
of pika, we considered and evaluated the best available scientific and 
commercial information. Below, we provide a summary of our analysis of 
threats to the five recognized subspecies of the American pika and to 
the species as a whole.

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

    The following potential factors that may affect the habitat or 
range of American pika are discussed in this section: (1) Climate 
change; (2) livestock grazing; (3) native plant succession; (4) 
invasive plant species; and (5) fire suppression.

Climate Change

    Climate change is a potential threat to the long-term survival of 
the American pika. Thermal and precipitation regime modifications may 
cause direct adverse effects to individuals or populations. Climate 
change has the potential to contribute to the loss of and change in 
pika habitat and enhance negative ecological and anthropogenic effects.

The Science of Climate Change

    The Intergovernmental Panel on Climate Change (IPCC) concluded that 
global climate change is occurring and is caused by human activities, 
such as the burning of fossil fuels and clearing of forests (Forster et 
al. 2007, pp. 135-136). The IPCC is a scientific intergovernmental body 
established by the World Meteorological Organization and the United 
Nations Environment Programme ``to assess scientific information 
related to climate change, to evaluate the environmental and socio-
economic consequences of climate change, and to formulate realistic 
response strategies'' (IPCC 2007, p. iii). The publications of the 
IPCC, specifically the four-volume IPCC Fourth Assessment Report: 
Climate Change 2007, constitute the best available science on global 
climate change. The IPCC Fourth Assessment Report: Climate Change 2007 
included the findings of three working groups composed of more than 500 
lead authors and 2,000 expert reviewers and provided objective 
scientific guidance to policymakers on the topic of climate change 
(IPCC 2007, p. iii). We believe the IPCC information is the best 
available scientific information on global climate change at a broad 
scale.
    Historical records analyzed by the IPCC demonstrate that global 
surface temperatures have risen (with regional variations) during the 
past 157 years, most strongly after the 1970s (Trenberth et al. 2007, 
p. 252). Globally, average surface temperatures have risen by 0.074 
[deg]C plus or minus 0.018 [deg]C (0.13 [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).
    Changes in the amount, intensity, frequency, and type of 
precipitation have been summarized by the IPCC (Trenberth et al. 2007, 
p. 262). The warming of global temperatures has increased the 
probability of precipitation falling as rain rather than snow, 
especially in near-freezing situations, such as the beginning and end 
of the snow season (Trenberth et al. 2007, p. 263). In many Northern 
Hemisphere regions, this has caused a reduced snowpack, which can 
greatly alter water resources throughout the year (Trenberth et al. 
2007, p. 263). As a result of thermal and precipitation regime changes, 
the IPCC expects the snowline (the lower elevation of year-round snow) 
in mountainous regions to rise 150 m (492 ft) for every 1 [deg]C (1.8 
[deg]F) increase in temperature (Christenson et al. 2007, p. 886). 
These predictions are consistent with regional predictions for the 
Sierra Nevada in California that calculate that year-round snow will be 
virtually absent below 1,000 m (3,280 ft) by the end of the 21st 
century under a high emissions scenario (Cayan et al. 2006, p. 32).
    Scientists at climate research institutions in the United States 
and in over a dozen countries worldwide, have

[[Page 6445]]

generated projections of future climatic conditions both globally and 
in the United States, which includes the range of the American pika. 
These projections were assessed and synthesized in the Fourth 
Assessment Report of the IPCC. The United States Global Change Research 
Program (USGCRP) coordinates climate change research from 13 
departments and agencies and was mandated by Congress in the Global 
Change Research Act of 1990 to, ``assist the Nation and the world to 
understand, assess, predict, and respond to human-induced and natural 
processes of global change.'' The IPCC has predicted global average 
surface warming during the 21st century is likely between 1.1 and 6.4 
[deg]C (2.0 and 11.5 [deg]F), depending on the emissions scenario, and 
taking into account other sources of uncertainty in the projections 
(Solomon et al. 2007, p. 70, Table TS. 6). The recent USGCRP assessment 
of climate impacts (Karl et al., 2009, pp. 129, 135) also adopts the 
IPCC range of temperature projections for different United States 
regions.
    On a regional scale, North America is likely to exceed the global 
mean warming in most areas (Christenson et al. 2007, p. 850). 
Specifically, warming is likely to be largest in winter in northern 
regions of North America, with minimum winter temperatures likely 
rising more than the global average (Christenson et al. 2007, p. 850). 
Across 21 global climate models using a mid-level emissions scenario, 
the IPCC predicted that the average annual temperature in western North 
America (covering the entire range of the American pika) will increase 
between 2.1 and 5.7 [deg]C (median 3.4 [deg]C) (3.8 and 10.3 [deg]F 
(median 6.1 [deg]F)) during the 21st century (Christenson et al. 2007, 
p. 856). The 2009 USGCRP impacts report projects the Southwest to warm 
2 to 6 [deg]C (4 to 10 [deg]F) relative to the 1960-1979 baseline (Karl 
et al. 2009, p. 129) and the Northwest to warm by ``another 2 to 6 
[deg]C (3 to 10 [deg]F)'' by the end of the century (Karl et al. 2009, 
p. 135).
    In the 20th century, the Pacific Northwest and western United 
States experienced annual average temperature increases of 0.6 to 1.7 
[deg]C (1.1 to 3.1 [deg]F) and 1.1 to 2.8 [deg]C (2.0 to 5.0 [deg]F), 
respectively (Parson et al. 2001, p. 248; Smith et al. 2001, p. 220). 
Temperature increases are expected to affect precipitation, snowpack, 
and snowmelt in the range of the American pika. Climate warming 
corresponds with a reduced mountain snowpack (Mote et al. 2005 and 
Regonda et al. 2005 cited in Vicuna and Dracup 2007, p. 330; Trenberth 
et al. 2007, p. 310) and a trend toward earlier snowmelt in western 
North America (Stewart et al. 2004, pp. 217, 219, 223). The IPCC 
concluded that snow-season length and depth of snowpack are very likely 
to decrease in most of North America (Christenson et al. 2007, p. 850). 
Leung et al. (2004, p. 75) concluded that future warming increases in 
the western United States will cause increased rainfall and decreased 
snowfall, resulting in reduced snow accumulation or earlier snowmelt. 
Similarly, Rauscher et al. (2008, p. 4) concluded that increased 
temperatures in the late 21st century could cause early-season 
snowmelt-driven runoff to occur as much as 2 months earlier than 
presently in the western United States.
    The above information applies at large, general scales. To 
understand the changes likely to occur in pika habitat, we worked with 
the National Oceanic and Atmospheric Administration (NOAA) to assess 
the best available climate science across the range of the American 
pika (NOAA 2009, p. 4). The NOAA study reviewed historical climate 
observations and climate projections of surface temperatures for 20-
year periods centered on 2025, 2050, and 2100 in alpine and subalpine 
mountain areas that are habitat for the American pika. Because model 
projections for precipitation are less reliable than for temperature in 
this region, their report focused primarily on temperature (NOAA 2009, 
pp. 10, 15). We primarily relied on this report to perform 
deterministic risk assessments of increased temperature in the 
foreseeable future to American pika populations throughout their range 
in the western United States. In addition, we used information on 
historical climate observations to supplement previous peer-reviewed 
publications and other reports from the literature to assess how 
temperature increases may have affected pikas in recent decades.
    The NOAA's analysis (NOAA 2009, p. 9) revealed an evident warming 
trend between 1950 and 2007 in the western United States. Strong 
warming trends occurred across 89 percent of the western United States 
and 37 to 42 percent of western United States mountain ranges (Das et 
al. 2009, cited in NOAA 2009, p. 9). Within the western United States, 
warming was documented and is attributable to anthropogenic climate 
change (Bonfils et al. 2008, cited in NOAA 2009, p. 11). Some studies 
(Barnett et al. 2008, p. 1080; Pierce et al. 2008, p. 6436) have 
estimated that up to about half of the trends in temperature and 
associated hydrologic variables can be attributed to anthropogenic 
causes. Natural climate variability may account for the remainder of 
the observed climate change in the western United States, and will 
likely play a role in the future climate of that region.
    Changes in the hydrologic cycle, including timing of snowmelt 
runoff, amount of precipitation falling as snow versus rain, and spring 
snow water equivalent, have been documented in the mountains of western 
North American and attributed to anthropogenic causes (multiple 
references cited in NOAA 2009, p. 8), with the exception of some high-
elevation areas, especially in the Rocky Mountains. Most of the 
reduction in snowpack in the western United States has occurred below 
about 2,500 m (8,200 ft) (Regonda et al. 2005, cited in NOAA 2009, p. 
9). This elevation is near the lower limit of American pikas' elevation 
range (Smith and Weston 1990, p. 2); therefore, it can be inferred that 
the majority of pika habitat in mountainous areas has not experienced 
the large changes in the hydrologic cycle seen at lower elevations.

Climate Change and Pika Biology

    Several climate variables are relevant to persistence of American 
pika populations because past and present trends in climate have been 
identified as having important physiological, ecological, and 
demographic consequences. These climate variables include, but may not 
be limited to, number of extremely hot or cold days, average summer 
temperatures, and duration of snow cover (Beever et al. 2009, pp. 5, 
10, 16-18).
    In general, pika biologists agree that temperatures below the 
habitat surface, such as in talus crevices, better approximate the 
conditions experienced by individual pikas because pikas rely on 
subsurface refugia to escape hotter summer daytime temperatures and 
obtain insulation in the colder winter months (Beever et al. 2009, p. 
9). Therefore, surface temperature variables may not be as useful as 
subsurface temperatures for predicting persistence or extirpations of 
pika populations in the face of climate change. However, data on 
subsurface temperatures within pika habitat vary depending on site-
specific conditions and are largely unavailable.
    Beever et al. (2009, p. 18) found that average summer (June-July-
August (J-J-A)) below-talus temperature was the best predictor of pika 
extirpation. They also discovered two other patterns: (1) The number of 
extremely cold and hot days based on estimates of below-talus 
temperatures was useful in predicting patterns of pika extirpations 
(Beever et al. 2009, p. 18); and (2) the majority of pika-extirpated 
sites were covered with

[[Page 6446]]

snow for only 2 weeks or less; whereas, the majority of pika-extant 
sites had continuous snow cover for greater than 2 weeks and as long as 
8.2 months (Beever et al. 2009, p. 16). Because American pikas are 
small and do not hibernate, reduced snowpack can mean a lack of 
insulation from cold winter temperatures (Morrison and Hik 2008, p. 
905). Exposure to colder temperatures could have an adverse effect on 
pika individuals and populations as a result of increased energy 
expenditure during a time of year where food resources are limited 
(Smith et al. 2004, p. 5). However, pika biologists have not determined 
the actual effects of acute cold-stress on pikas (Beever et al. 2009, 
p. 29).
    The population collapse of a closely related pika species, the 
collared pika (Ochotona collaris), was related to warmer winters that 
resulted in low snow accumulation (and, therefore, poor insulation 
value), increased frequency of freeze-thaw events, icing following 
winter rains, and late winter snowfalls that delay the start of the 
growing season (Morrison and Hik 2008, pp. 104-105, 110). Following a 
decline in population abundance, populations recovered in subsequent 
years, in some cases to near pre-decline levels (Morrison and Hik 2007, 
pp. 902-903). Declines in snowpack and earlier montane snowmelt are 
predicted to occur within the next century, and winter survival of the 
American pika may consequently decrease. Alternatively, earlier 
snowmelt could improve pika survival and positively affect American 
pika populations (Morrison and Hik 2007, p. 905). Based on the 
available information there does not appear to be a direct line of 
evidence linking reduced snowpack to reductions in American pika 
populations.
    Several lines of evidence have been used to suggest that thermal 
stress will adversely impact the American pika. Wolf et al. (2007, p. 
43) pointed out that increasing temperatures will eliminate cool, moist 
refugia in talus habitat, causing individuals to be unable to 
thermoregulate in summer months. However, Millar and Westfall (2009, p. 
25) stated that non-rock-ice features will likely become warmer and 
more marginal for pikas, but environments with rock-ice features are 
highly likely to remain buffered against temperature change due to the 
insulation of rock features. Millar and Westfall (2009, p. 10) 
documented that 83 percent of over 400 surveyed pika sites in the 
Sierra Nevada and Great Basin occurred in rock-ice landforms, 
indicating that pikas have a preference for these types of 
environments. Therefore, we expect pika habitat that contains rock-ice 
features or features that are similar to rock-ice (i.e., talus or 
talus-like environments) to be buffered from rising surface 
temperatures. We are not aware of any studies that have identified the 
distribution of these types of features, and thus we are not able to 
use that type of information to help us increase the sensitivity of our 
climate change threats analysis.
    Wolf et al. (2007, p. 44) also state that, even if the talus 
refugia remain cool, ambient external temperatures may reduce an 
individual's ability to forage during midday. They assert that if pika 
individuals cannot adequately forage in the summer months, they may not 
have the required body mass or haypile volume needed for winter 
survival. However, pikas at low elevations restrict their activity when 
temperatures exceed their thermal tolerance but are able to obtain 
enough food and overwintering vegetation (hay pile) during the morning 
and evening so that long-term population persistence is not affected 
(Smith 1974a, pp. 1117-1118; Smith 1974b, pp. 1370-1372; Smith 2009, p. 
4).
    Warmer summer temperatures may affect the ability of juvenile pikas 
to successfully disperse and colonize new areas (Smith 1974a, p. 1112; 
Smith 1978, p. 137; Wolf et al. 2007, p. 44). Because dispersal occurs 
on the habitat surface, dispersing pikas are exposed to the hottest 
temperatures on the surface of their environmen