[Federal Register Volume 76, Number 28 (Thursday, February 10, 2011)]
[Proposed Rules]
[Pages 7634-7679]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-2400]



[[Page 7633]]

Vol. 76

Thursday,

No. 28

February 10, 2011

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 Pacific Walrus as Endangered or Threatened; 
Proposed Rule

  Federal Register / Vol. 76, No. 28 / Thursday, February 10, 2011 / 
Proposed Rules  

[[Page 7634]]


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

DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R7-ES-2009-0051; MO 92210-0-0008-B2]


Endangered and Threatened Wildlife and Plants; 12-Month Finding 
on a Petition to List the Pacific Walrus as Endangered or Threatened

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of 12-month petition finding.

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

SUMMARY: We, the U.S. Fish and Wildlife Service, announce a 12-month 
finding on a petition to list the Pacific walrus (Odobenus rosmarus 
divergens) as endangered or threatened and to designate critical 
habitat under the Endangered Species Act of 1973, as amended. After 
review of all the available scientific and commercial information, we 
find that listing the Pacific walrus as endangered or threatened is 
warranted. Currently, however, listing the Pacific walrus is precluded 
by higher priority actions to amend the Lists of Endangered and 
Threatened Wildlife and Plants. Upon publication of this 12-month 
petition finding, we will add Pacific walrus to our candidate species 
list. We will develop a proposed rule to list the Pacific walrus as our 
priorities allow. We will make any determination on critical habitat 
during development of the proposed listing rule. Consistent with 
section 4(b)(3)(C)(iii) of the Endangered Species Act, we will review 
the status of the Pacific walrus through our annual Candidate Notice of 
Review.

DATES: The finding announced in this document was made on February 10, 
2011.

ADDRESSES: This finding and supporting documentation are available on 
the Internet at http://www.regulations.gov at Docket Number FWS-R7-ES-
2009-0051. A range map of the three walrus subspecies and a more 
detailed map of the Pacific walrus range are available at the following 
Web site: http://alaska.fws.gov/fisheries/mmm/walrus/wmain.htm. 
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, Alaska Regional Office, 1011 East 
Tudor Road, Anchorage, AK 99503. Please submit any new information, 
materials, comments, or questions concerning this finding to the above 
address.

FOR FURTHER INFORMATION CONTACT: James MacCracken, Marine Mammals 
Management, Alaska Regional Office (see ADDRESSES); by telephone: 800-
362-5148; or by facsimile: 907-786-3816. 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 whether the petitioned action is: (a) Not warranted, (b) 
warranted, or (c) 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 Actions

    On February 8, 2008, we received a petition dated February 7, 2008, 
from the Center for Biological Diversity, requesting that the Pacific 
walrus be listed as endangered or threatened under the Act and that 
critical habitat be designated. The petition included supporting 
information regarding the species' ecology and habitat use patterns, 
and predicted changes in sea-ice habitats and ocean conditions that may 
impact the Pacific walrus. We acknowledged receipt of the petition in a 
letter to the Center for Biological Diversity, dated April 9, 2008. In 
that letter, we stated that an emergency listing was not warranted and 
that all remaining available funds in the listing program for Fiscal 
Year (FY) 2008 had already been allocated to the U.S. Fish and Wildlife 
Service's (Service) highest priority listing actions and that no 
listing funds were available to further evaluate the Pacific walrus 
petition in FY 2008.
    On December 3, 2008, the Center for Biological Diversity filed a 
complaint in U.S. District Court for the District of Alaska for 
declaratory judgment and injunctive relief challenging the failure of 
the Service to make a 90-day finding on their petition to list the 
Pacific walrus, pursuant to section 4(b)(3) of the Endangered Species 
Act, 16 U.S.C. 1533(b)(3), and the Administrative Procedure Act, 5 
U.S.C. 706(1). On May 18, 2009, a settlement agreement was approved in 
the case of Center for Biological Diversity v. U.S. Fish and Wildlife 
Service, et al. (3:08-cv-00265-JWS), requiring us to submit our 90-day 
finding on the petition to the Federal Register by September 10, 2009. 
On September 10, 2009, we made our 90-day finding that the petition 
presented substantial scientific information indicating that listing 
the Pacific walrus may be warranted (74 FR 46548). On August 30, 2010, 
the Court approved an amended settlement agreement requiring us to 
submit our 12-month finding to the Federal Register by January 31, 
2011. This notice constitutes the 12-month finding on the February 7, 
2008, petition to list the Pacific walrus as endangered or threatened.
    This 12-month finding is based on our consideration and evaluation 
of the best scientific and commercial information available. We 
reviewed the information provided in the petition submitted to the 
Service by the Center for Biological Diversity, information available 
in our files, and other available published and unpublished 
information. Additionally, in response to our Federal Register notice 
of September 10, 2009, requesting information from the public, as well 
as our September 10, 2010 press release, and other outreach efforts 
requesting new information from the public, we received roughly 30,000 
submissions, which we have considered in making this finding, including 
information from the U.S. Marine Mammal Commission, the State of 
Alaska, the Alaska North Slope Borough, the Eskimo Walrus Commission, 
the Humane Society of the United States, the Center for Biological 
Diversity, the American Petroleum Institute, and many interested 
citizens. We also consulted with recognized Pacific walrus experts and 
Federal, State, and Tribal agencies.

Species Information

Taxonomy and Species Delineation
    The walrus (Odobenus rosmarus) is the only living representative of 
the family Odobenidae, a group of marine carnivores that was highly 
diversified in

[[Page 7635]]

the late Miocene and early Pliocene (Kohno 2006, pp. 416-419; Harington 
2008, p. 26). Fossil evidence suggests that the genus evolved in the 
North Pacific Ocean and dispersed throughout the Arctic Ocean and North 
Atlantic during interglacial phases of the Pleistocene (Harington and 
Beard 1992, pp. 311-319; Dyke et al. 1999, p. 60; Harington 2008, p. 
27).
    Three modern subspecies of walruses are generally recognized 
(Wozencraft 2005, p. 525; Integrated Taxonomic Information System, 
2010, p. 1): The Atlantic walrus (O. r. rosmarus), which ranges from 
the central Canadian Arctic eastward to the Kara Sea (Reeves 1978, pp. 
2-20); the Pacific walrus (O. r. divergens), which ranges across the 
Bering and Chukchi Seas (Fay 1982, pp. 7-21); and the Laptev walrus (O. 
r. laptevi), which is represented by a small, geographically isolated 
population of walruses in the Laptev Sea (Heptner et al. 1976, p. 34; 
Vishnevskaia and Bychkov 1990, pp. 155-176; Andersen et al. 1998, p. 
1323; Wozencraft 2005, p. 595; Jefferson et al. 2008, p. 376). Atlantic 
and Pacific walruses are genetically and morphologically distinct from 
each other (Cronin et al. 1994, p. 1035), likely as a result of range 
fragmentation and differentiation during glacial phases of extensive 
Arctic sea-ice cover (Harington 2008, p. 27). Although geographically 
isolated and ecologically distinct, walruses from the Laptev Sea appear 
to be more closely related to Pacific walruses (Lindqvist et al. 2009, 
pp. 119-121).
    Pacific walruses are ecologically distinct from other walrus 
populations, primarily because they undergo significant seasonal 
migrations between the Bering and the Chukchi Seas and rely principally 
on broken pack ice habitat to access offshore breeding and feeding 
areas (Fay 1982, p. 279) (see Species Distribution, below). In 
contrast, Atlantic walruses, which are represented by several small 
discrete groups of animals distributed from the central Canadian Arctic 
eastward to the Kara Sea, exhibit smaller seasonal movements and feed 
primarily in coastal areas because the continental shelf is narrow over 
much of their range. The majority of productive feeding areas used by 
Atlantic walruses are accessible from the coast, and all age classes 
and gender groups use terrestrial haulouts during ice-free seasons 
(Born et al. 2003, p. 356; COSEWIC 2006, p. 15; Laidre et al. 2008, pp. 
S104, S115).
    The Pacific walrus is generally considered a single population, 
although some heterogeneity has been documented. Jay et al. (2008, p. 
938) found some differences in the ratio of trace elements in the teeth 
of Pacific walruses sampled in winter from two breeding areas 
(southeast Bering Sea and St. Lawrence Island), suggesting that the 
sampled animals had a history of feeding in different regions. Scribner 
et al. (1997, p. 180), however, found no difference in mitochondrial 
and nuclear DNA among Pacific walruses sampled from different breeding 
areas. Pacific walruses are identified and managed in the United States 
and the Russian Federation (Russia) as a single population (Service 
2010, p. 1).
Species Description
    Walruses are readily distinguished from other Arctic pinnipeds 
(aquatic carnivorous mammals with all four limbs modified into 
flippers, this group includes seals, sea lions, and walruses) by their 
enlarged upper canine teeth, which form prominent tusks. The family 
name Odobenidae (tooth walker), is based on observations of walruses 
using their tusks to pull themselves out of the water. Males, which 
have relatively larger tusks than females, also tend to have broader 
skulls (Fay 1982, pp. 104-108). Walrus tusks are used as offensive and 
defensive weapons (Kastelein 2002, p. 1298). Adult males use their 
tusks in threat displays and fighting to establish dominance during 
mating (Fay et al. 1984, p. 93), and animals of both sexes use threat 
displays to establish and defend positions on land or ice haulouts (Fay 
1982, pp. 134-138). Walruses also use their tusks to anchor themselves 
to ice floes when resting in the water during inclement weather (Fay 
1982, pp. 134-138; Kastelein 2002, p. 1298).
    The Pacific walrus is the largest pinniped species in the Arctic. 
At birth, calves are approximately 65 kilograms (kg) (143 pounds (lb)) 
and 113 centimeters (cm) (44.5 inches (in)) long (Fay 1982, p. 32). 
After the first 7 years of life, the growth rate of female walruses 
declines rapidly, and they reach a maximum body size by approximately 
10 years of age. Adult females can reach lengths of up to 3 meters (m) 
(9.8 feet (ft)) and weigh up to 1,100 kg (2,425 lb). Male walrus tend 
to grow faster and for a longer period of time than females. They 
usually do not reach full adult body size until they are 15 to 16 years 
of age. Adult males can reach lengths of 3.5 m (11.5 ft) and can weigh 
more than 2,000 kg (4,409 lb) (Fay 1982, p. 33).
Behavior
    Walruses are social and gregarious animals. They tend to travel in 
groups and haul out of the water to rest on ice or land in densely 
packed groups. On land or ice, in any season, walruses tend to lie in 
close physical contact with each other. Young animals often lie on top 
of adults. Group size can range from a few individuals up to several 
thousand animals (Gilbert 1999, p. 80; Kastelein 2002, p. 1298; 
Jefferson et al. 2008, p. 378). At any time of the year, when groups 
are disturbed, stampedes from a haulout can result in injuries and 
mortalities. Calves and young animals are particularly vulnerable to 
trampling injuries (Fay 1980, pp. 227-227; Fay and Kelly 1980, p. 226).
    The reaction of walruses to disturbance ranges from no reaction to 
escape into the water, depending on the circumstances (Fay et al. 1984, 
pp. 13-14). Many factors play into the severity of the response, 
including the age and sex of the animals, the size and location of the 
group (on ice, in water, on land), their distance from the disturbance, 
and the nature and intensity of the disturbance (Fay et al. 1984, pp. 
14, 114-119). Females with calves appear to be most sensitive to 
disturbance, and animals on shore are more sensitive than those on ice 
(Fay et al. 1984, p. 114). A fright response caused by disturbance can 
cause stampedes on a haulout, resulting in injuries and mortalities 
(Fay and Kelly 1980, pp. 241-244).
    Mating occurs primarily in January and February in broken pack ice 
habitat in the Bering Sea. Breeding bulls follow herds of females and 
compete for access to groups of females hauled out onto sea ice (Fay 
1982, pp. 193-194). Males perform visual and acoustical displays in the 
water to attract females and defend a breeding territory. Subdominant 
males remain on the periphery of these aggregations and apparently do 
not display. Intruders into display areas are met with threat displays 
and physical attacks. Individual females leave the resting herd to join 
a male in the water where copulation occurs (Fay et al. 1984, pp. 89-
99; Sjare and Stirling 1996, p. 900). Gestation lasts 15 to 16 months 
(Fay 1982, p. 197) and pregnancies are spaced at least 2 years apart 
(Fay 1982, p. 206). Calving occurs on sea ice, most typically in May, 
before the northward spring migration (Fay 1982, pp. 199-200). Mothers 
and newborn calves stay mostly on ice floes during the first few weeks 
of life (Fay et al. 1984, p. 12).
    The social bond between the mother and calf is very strong, and it 
is unusual for a cow to become separated from her calf (Fay 1982, p. 
203). The calf normally remains with its mother for at least 2 years, 
sometimes longer, if not supplanted by a new calf (Fay 1982, pp. 206-
211). After separation from their

[[Page 7636]]

mother, young females tend to remain with groups of adult females, 
whereas young males gradually separate from the females and begin to 
associate with groups of other males. Individual social status appears 
to be based on a combination of body size, tusk size, and 
aggressiveness. Individuals do not necessarily associate with the same 
group of animals and must continually reaffirm their social status in 
each new aggregation (Fay 1982, p. 135; NAMMCO 2004, p. 43).
Species Distribution
    Pacific walruses range across the shallow continental shelf waters 
of the northern Bering Sea and Chukchi Sea, occasionally ranging into 
the East Siberian Sea and Beaufort Sea (Fay 1982, pp. 7-21; Figure 1 in 
Garlich-Miller et al. 2011). Waters deeper than 100 m (328 ft) and the 
extent of the pack ice are factors that limit distribution to the north 
(Fay 1982, p. 23). Walruses are rarely spotted south of the Alaska 
Peninsula and Aleutian archipelago; however, migrant animals (mostly 
males) are occasionally reported in the North Pacific (Service 2010, 
unpublished data).
    Pacific walruses are highly mobile, and their distribution varies 
markedly in response to seasonal and interannual variations in sea-ice 
cover. During the January to March breeding season, walruses congregate 
in the Bering Sea pack ice in areas where open leads (fractures in sea 
ice caused by wind drift or ocean currents), polynyas (enclosed areas 
of unfrozen water surrounded by ice) or thin ice allow access to water 
(Fay 1982, p. 21; Fay et al. 1984, pp. 89-99). The specific location of 
winter breeding aggregations varies annually depending upon the 
distribution and extent of ice. Breeding aggregations have been 
reported southwest of St. Lawrence Island, Alaska; south of Nunivak 
Island, Alaska; and south of the Chukotka Peninsula in the Gulf of 
Anadyr, Russia (Fay 1982, p. 21; Mymrin et al. 1990, pp. 105-113; 
Figure 1 in Garlich-Miller et al. 2011).
    In spring, as the Bering Sea pack ice deteriorates, most of the 
population migrates northward through the Bering Strait to summer 
feeding areas over the continental shelf in the Chukchi Sea. However, 
several thousand animals, primarily adult males, remain in the Bering 
Sea during the summer months, foraging from coastal haulouts in the 
Gulf of Anadyr, Russia, and in Bristol Bay, Alaska (Figure 1 in 
Garlich-Miller et al. 2011).
    Summer distributions (both males and females) in the Chukchi Sea 
vary annually, depending upon the extent of sea ice. When broken sea 
ice is abundant, walruses are typically found in patchy aggregations 
over continental shelf waters. Individual groups may range from less 
than 10 to more than 1,000 animals (Gilbert 1999, pp. 75-84; Ray et al. 
2006, p. 405). Summer concentrations have been reported in loose pack 
ice off the northwestern coast of Alaska, between Icy Cape and Point 
Barrow, and along the coast of Chukotka, Russia, as far west as Wrangel 
Island (Fay 1982, pp. 16-17; Gilbert et al. 1992, pp. 1-33; Belikov et 
al. 1996, pp. 267-269). In years of low ice concentrations in the 
Chukchi Sea, some animals range east of Point Barrow into the Beaufort 
Sea; walruses have also been observed in the Eastern Siberian Sea in 
late summer (Fay 1982, pp. 16-17; Belikov et al. 1996, pp. 267-269). 
The pack ice of the Chukchi Sea usually reaches its minimum extent in 
September. In years when the sea ice retreats north beyond the 
continental shelf, walruses congregate in large numbers (up to several 
tens of thousands of animals in some locations) at terrestrial haulouts 
on Wrangel Island and other sites along the northern coast of the 
Chukotka Peninsula, Russia, and northwestern Alaska (Fay 1982, p. 17; 
Belikov et al. 1996, pp. 267-269; Kochnev 2004, pp. 284-288; Ovsyanikov 
et al. 2007, pp. 1-4; Kavry et al. 2008, pp. 248-251).
    In late September and October, walruses that summered in the 
Chukchi Sea typically begin moving south in advance of the developing 
sea ice. Satellite telemetry data indicate that male walruses that 
summered at coastal haulouts in the Bering Sea also begin to move 
northward towards winter breeding areas in November (Jay and Hills 
2005, p. 197). The male walruses' northward movement appears to be 
driven primarily by the presence of females at that time of year 
(Freitas et al. 2009, pp. 248-260).
Foraging and Prey
    Walruses consume mostly benthic (region at the bottom of a body of 
water) invertebrates and are highly adapted to obtain bivalves (Fay 
1982, p. 139; Bowen and Siniff 1999, p. 457; Born et al. 2003, p. 348; 
Dehn et al. 2007, p. 176; Boveng et al. 2008, pp. 17-19; Sheffield and 
Grebmeier 2009, pp. 766-767). Fish and other vertebrates have 
occasionally been found in their stomachs (Fay 1982, p. 153; Sheffield 
and Grebmeier 2009, p. 767). Walruses root in the bottom sediment with 
their muzzles and use their whiskers to locate prey items. They use 
their fore-flippers, nose, and jets of water to extract prey buried up 
to 32 cm (12.6 in) (Fay 1982, p. 163; Oliver et al. 1983, p. 504; 
Kastelein 2002, p. 1298; Levermann et al. 2003, p. 8). The foraging 
behavior of walruses is thought to have a major impact on benthic 
communities in the Bering and Chukchi Seas (Oliver et al. 1983, pp. 
507-509; Klaus et al. 1990, p. 480). Ray et al. (2006, pp. 411-413) 
estimate that walruses consume approximately 3 million metric tons 
(3,307 tons) of benthic biomass annually, and that the area affected by 
walrus foraging is in the order of thousands of square kilometers (sq 
km) (thousands of square miles (sq mi)) annually. Consequently, 
walruses play a major role in benthic ecosystem structure and function, 
which Ray et al. (2006, p. 415) suggested increased nutrient flux and 
productivity.
    The earliest studies of food habits were based on examination of 
stomachs from walruses killed by hunters. These reports indicated that 
walruses were primarily feeding on bivalves (clams), and that non-
bivalve prey was only incidentally ingested (Fay 1982, p. 145; 
Sheffield et al. 2001, p. 311). However, these early studies did not 
take into account the differential rate of digestion of prey items 
(Sheffield et al. 2001, p. 311). Additional research indicates that 
stomach contents include over 100 taxa of benthic invertebrates from 
all major phyla (Fay 1982, p. 145; Sheffield and Grebmeier 2009, p. 
764), and while bivalves remain the primary component, walruses are not 
adapted to a diet solely of clams. Other prey items have similar 
energetic benefits (Wacasey and Atkinson 1987, pp. 245-247). Based on 
analysis of the contents from fresh stomachs of Pacific walruses 
collected between 1975 and 1985 in the Bering Sea and Chukchi Sea, prey 
consumption likely reflects benthic invertebrate composition (Sheffield 
and Grebmeier 2009, pp. 764-768). Of the large number of different 
types of prey, statistically significant differences between males and 
females from the Bering Sea were found in the occurrence of only two 
prey items, and there were no statistically significant differences in 
results for males and females from the Chukchi Sea (Sheffield and 
Grebmeier 2009, pp. 765). Although these data are for Pacific walrus 
stomachs collected 25-35 years ago, we have no reason to believe there 
has been a change in the general pattern of prey use described here.
    Walruses typically swallow invertebrates without shells in their 
entirety (Fay 1982, p. 165). Walruses remove the soft parts of mollusks 
from their shells by suction, and discard the shells (Fay 1982, pp. 
166-167). Born et al. (2003, p. 348) reported that Atlantic

[[Page 7637]]

walruses consumed an average of 53.2 bivalves (range 34 to 89) per 
dive. Based on caloric need and observations of captive walruses, 
walruses require approximately 29 to 74 kg (64 to 174 lbs) of food per 
day (Fay 1982, p. 160). Adult males forage little during the breeding 
period (Fay 1982, pp. 142, 159-161; Ray et al. 2006, p. 411), while 
lactating females may eat two to three times that of nonpregant, 
nonlactating females (Fay 1982, p.159). Calves up to 1 year of age 
depend primarily on their mother's milk (Fay 1982, p. 138) and are 
gradually weaned in their second year (Fisher and Stewart 1997, pp. 
1165-1175).
    Although walruses are capable of diving to depths of more than 250 
m (820 ft) (Born et al. 2005, p. 30), they usually forage in waters of 
80 m (262 ft) or less (Fay and Burns 1988, p. 239; Born et al. 2003, p. 
348; Kovacs and Lydersen 2008, p. 138), presumably because of higher 
productivity of their benthic foods in shallow waters (Fay and Burns 
1988, pp. 239-240; Carey 1991, p. 869; Jay et al. 2001, p. 621; 
Grebmeier et al. 2006b, pp. 334-346; Grebmeier et al. 2006a, p. 1461). 
Walruses make foraging trips from land or ice haulouts that range from 
a few hours up to several days and up to 100 kilometers (km) (60 miles 
(mi)) (Jay et al. 2001, p. 626; Born et al. 2003, p. 349; Ray et al. 
2006, p. 406; Udevitz et al. 2009, p. 1122). Walruses tend to make 
shorter and more frequent foraging trips when sea ice is used as a 
foraging platform compared to terrestrial haulouts (Udevitz et al. 
2009, p. 1122). Satellite telemetry data for walruses in the Bering Sea 
in April of 2004, 2005, and 2006 showed they spent an average of 46 
hours in the water between resting bouts on ice, which averaged 9 hours 
(Udevitz et al. 2009, p. 1122). Because females and young travel with 
the retreating pack ice in the spring and summer, they are passively 
transported northward over feeding grounds across the continental 
shelves of the Bering and Chukchi Seas. Male walruses appear to have 
greater endurance than females, with foraging excursions from land 
haulouts that can last up to 142 hours (about 6 days) (Jay et al. 2001, 
p. 630).
Sea-Ice Habitats
    The Pacific walrus is an ice-dependent species that relies on sea 
ice for many aspects of its life history. Unlike other pinnipeds, 
walruses are not adapted for a pelagic existence and must haul out on 
ice or land regularly. Floating pack ice serves as a substrate for 
resting between feeding bouts (Ray et al. 2006, p. 404), breeding 
behavior (Fay et al. 1984, pp. 89-99), giving birth (Fay 1982, p. 199), 
and nursing and care of young (Kelly 2001, pp. 43-55). Sea ice provides 
access to offshore feeding areas over the continental shelf of the 
Bering and Chukchi Seas, passive transportation to new feeding areas 
(Richard 1990, p. 21; Ray et al. 2006, pp. 403-419), and isolation from 
terrestrial predators (Richard 1990, p. 23; Kochnev 2004, p. 286; 
Ovsyanikov et al. 2007, pp. 1-4). Sea ice provides an extensive 
substrate upon which the risk of predation and hunting is greatly 
reduced (Kelly 2001, pp. 43-55; Fay 1982, p. 26).
    Sea ice in the Northern Hemisphere is comprised of first-year sea 
ice that formed in the most recent autumn-winter period, and multi-year 
ice that has survived at least one summer melt season. Sea-ice habitats 
for walruses include openings or leads that provide access to the water 
and to food resources. Walruses generally do not use multi-year ice or 
highly compacted first-year ice in which there is an absence of 
persistent leads or polynyas (Richard 1990, p. 21). Expansive areas of 
heavy ice cover are thought to play a restrictive role in walrus 
distributions across the Arctic and serve as a barrier to the mixing of 
populations (Fay 1982, p. 23; Dyke et al. 1999, pp. 161-163; Harington 
2008, p. 35). Walruses generally do not occur farther south than the 
maximum extent of the winter pack ice, possibly due to their reliance 
on sea ice for breeding and rearing young (Fay et al. 1984, pp. 89-99) 
and isolation from terrestrial predators (Kochnev 2004, p. 286; 
Ovsyanikov et al. 2007, pp. 1-4), or because of the higher densities of 
benthic invertebrates in northern waters (Grebmeier et al. 2006a, pp. 
1461-1463).
    Walruses generally occupy first-year ice that is greater than 20 cm 
(7.9 in) thick and are not found in areas of extensive, unbroken ice 
(Fay 1982, pp. 21, 26; Richard 1990, p. 23). Thus, in winter they 
concentrate in areas of broken pack ice associated with divergent ice 
flow or along the margins of persistent polynyas (Burns et al. 1981, 
pp. 781-797; Fay et al. 1984, pp. 89-99; Richard 1990, p. 23) in areas 
with abundant food resources (Ray et al. 2006, p. 406). Females with 
young generally spend the summer months in pack ice habitats of the 
Chukchi Sea, where they feed intensively between bouts of resting and 
suckling their young. Some authors have suggested that the size and 
topography of individual ice floes are important features in the 
selection of ice haulouts, noting that some animals have been observed 
returning to the same ice floe between feeding bouts (Ray et al. 2006, 
p. 406). However, it has also been noted that walruses can and will 
exploit a fairly broad range of ice types and ice concentrations in 
order to stay in preferred foraging or breeding areas (Freitas et al. 
2009, p. 247; Jay et al. 2010a, p. 300). Walruses tend to make shorter 
foraging excursions when they are using sea ice rather than land 
haulouts (Udevitz et al. 2009, p. 1122), presumably because it is more 
energetically efficient for them to haulout on ice near productive 
feeding areas than forage from shore. Fay (1982, p. 25) notes that 
several authors reported that when walruses had the choice of ice or 
land for a resting place, ice was always selected.
Terrestrial Habitats (Coastal Haulouts)
    When suitable sea ice is not available, walruses haul out on land 
to rest. A wide variety of substrates, ranging from sand to boulders, 
are used. Isolated islands, points, spits, and headlands are occupied 
most frequently. The primary consideration for a terrestrial haulout 
site appears to be isolation from disturbances and predators, although 
social factors, learned behavior, protection from strong winds and 
surf, and proximity to food resources also likely influence the choice 
of terrestrial haulout sites (Richard 1990, p. 23). Walruses tend to 
use established haulout sites repeatedly and exhibit some degree of 
fidelity to these sites (Jay and Hills 2005, pp. 192-202), although the 
use of coastal haulouts appears to fluctuate over time, possibly due to 
localized prey depletion (Garlich-Miller and Jay 2000, pp. 58-65). 
Human disturbance is also thought to influence the choice of haulout 
sites; many historic haulouts in the Bering Sea were abandoned in the 
early 1900s when the Pacific walrus population was subjected to high 
levels of exploitation (Fay 1982, p. 26; Fay et al. 1984, p. 231).
    Adult male walruses use land-based haulouts more than females or 
young, and consequently, have a greater geographical distribution 
through the ice-free season. Many adult males remain in the Bering Sea 
throughout the ice-free season, making foraging trips from coastal 
haulouts in Bristol Bay, Alaska, and the Gulf of Anadyr, Russia (Figure 
1 in Garlich-Miller et al. 2011), while females and juvenile animals 
generally stay with the drifting ice pack throughout the year (Fay 
1982, pp. 8-19). Females with dependent young may prefer sea-ice 
habitats because coastal haulouts pose greater risk from trampling 
injuries and predation (Fay and Kelly 1980, pp. 226-245; Ovsyanikov et 
al. 1994, p. 80; Kochnev

[[Page 7638]]

2004, pp. 285-286; Ovsyanikov et al. 2007, pp. 1-4; Kavry et al. 2008, 
pp. 248-251; Mulcahy et al. 2009, p. 3). Females may also prefer sea-
ice habitats because they may have difficulty nourishing themselves 
while caring for a young calf that has limited swimming range (Cooper 
et al. 2006, p. 101; Jay and Fischbach 2008, p. 1).
    The numbers of male walruses using coastal haulouts in the Bering 
Sea during the summer months, and the relative uses of different 
coastal haulout sites in the Bering Sea have varied over the past 
century. Harvest records indicate that walrus herds were once common at 
coastal haulouts along the Alaska Peninsula and the islands of northern 
Bristol Bay (Fay et al. 1984, pp. 231-376). By the early 1950s, most of 
the traditional haulout areas in the Southern Bering Sea had been 
abandoned, presumably due to hunting pressure. During the 1950s and 
1960s, Round Island was the only regularly used haulout in Bristol Bay, 
Alaska. In 1960, the State of Alaska established the Walrus Islands 
State Game Sanctuary, which closed Round Island to hunting. Peak counts 
of walruses at Round Island increased from 1,000-2,000 animals in the 
late 1950s (Frost et al. 1983, pp. 379) to more than 10,000 animals in 
the early 1980s (Sell and Weiss, p. 12), but subsequently declined to 
2,000-5,000 over the past decade (Sell and Weiss 2010, p. 12). General 
observations indicate that declining walrus counts at Round Island may, 
in part, reflect a redistribution of animals to other coastal sites in 
the Bristol Bay region. For example, walruses have been observed 
increasingly regularly at the Cape Seniavin haulout on the Alaska 
Peninsula since the 1970s, and at Cape Peirce and Cape Newenham in 
northwest Bristol Bay since the early 1980s (Jay and Hills 2005, p. 
193; Figure 1 in Garlich-Miller et al. 2011).
    Traditional male summer haulouts along the Bering Sea coast of 
Russia include sites along the Kamchatka Peninsula, the Gulf of Anadyr 
(most notably Rudder and Meechkin spits), and Arakamchechen Island 
(Garlich-Miller and Jay 2000, pp. 58-65; Figure 1 in Garlich-Miller et 
al. 2011). Several of the southernmost haulouts along the coast of 
Kamchatka have not been occupied in recent years, and the number of 
animals in the Gulf of Anadyr has also declined in recent years 
(Kochnev 2005, p. 4). Factors influencing abundance at Bering Sea 
haulouts are poorly understood, but may include changes in prey 
densities near the haulouts, changes in population size, disturbance 
levels, and changing seasonal distributions (Jay and Hills 2005, p. 
198) (presumably mediated by sea-ice coverage or temperature).
    Historically, coastal haulouts along the Arctic (Chukchi Sea) coast 
have been used less consistently during the summer months than those in 
the Bering Sea because of the presence of pack ice (a preferred 
substrate) for much of the year in the Chukchi Sea. Since the mid-
1990s, reductions of summer sea ice coincided with a marked increase in 
the use of coastal haulouts along the Chukchi sea coast of Russia 
during the summer months (Kochnev 2004, pp. 284-288; Kavry et al. 2008, 
pp. 248-251). Large, mixed (composed of various age and sex groups) 
herds of walruses, up to several tens of thousands of animals, began to 
use coastal haulouts on Wrangel Island, Russia in the early 1990s, and 
several coastal haulouts along the northern Chukotka coastline of 
Russia have emerged in recent years, likely as a result of reductions 
in summer sea ice in the Chukchi Sea (Kochnev 2004, pp. 284-288; 
Ovsyanikov et al. 2007, pp. 1-4; Kavry et al. 2008, p. 248-251; Figure 
1 in Garlich-Miller et al. 2011).
    In 2007, 2009, and 2010, walruses were also observed hauling out in 
large numbers with mixed sex and age groups along the Chukchi Sea coast 
of Alaska in late August, September, and October (Thomas et al. 2009, 
p. 1; Service 2010, unpublished data). Monitoring studies conducted in 
association with oil and gas exploration suggest that the use of 
coastal haulouts along the Arctic coast of Alaska during the summer 
months is dependent upon the availability of sea ice. For example, in 
2006 and 2008, walruses foraging off the Chukchi Sea coast of Alaska 
remained with the ice pack over the continental shelf during the months 
of August, September, and October. However in 2007, 2009, and 2010, the 
pack ice retreated beyond the continental shelf and large numbers of 
walruses hauled out on land at several locations between Point Barrow 
and Cape Lisburne, Alaska (Ireland et al. 2009, p. xvi; Thomas et al. 
2009, p. 1; Service 2010, unpublished data; Figure 1 in Garlich-Miller 
et al. 2011).
    Transitory coastal haulouts have also been reported in late fall 
(October-November) along the southern Chukchi Sea coast, coinciding 
with the southern migration. Mixed herds of walruses frequently come to 
shore to rest for a few days to weeks along the coast before continuing 
on their migration to the Bering Sea. Cape Lisburne, Alaska, and Capes 
Serdtse-Kamen' and Dezhnev, Russia, are the most consistently used 
haulouts in the Chukchi Sea at this time of year (Garlich-Miller and 
Jay 2000, pp. 58-67). Large mixed herds of walruses have also been 
reported in late fall and early winter at coastal haulouts in the 
northern Bering Sea at the Punuk Islands and Saint Lawrence Island, 
Alaska; Big Diomede Island, Russia; and King Island, Alaska, prior to 
the formation of sea ice in offshore breeding and feeding areas (Fay 
and Kelly 1980, p. 226; Garlich-Miller and Jay 2000, pp. 58-67; Figure 
1 in Garlich-Miller et al. 2011).
Vital Rates
    Walruses have the lowest rate of reproduction of any pinniped 
species (Fay 1982, pp. 172-209). Although male walruses reach puberty 
at 6-7 years of age, they are unlikely to successfully compete for 
access to females until they reach full body size at 15 years of age or 
older (Fay 1982, p. 33; Fay et al. 1984, p. 96). Female walruses attain 
sexual maturity at 4-7 years of age (Fay 1982, pp. 172-209), and the 
median age of first birth ranges from approximately 8 to 10 years of 
age (Garlich-Miller et al. 2006, pp. 887-893). Because gestation lasts 
15-16 months, it extends through the following breeding season and 
thus, the minimum interval between successful births is 2 years. 
Ovulation may also be suppressed until the calf is weaned, raising the 
birth interval to 3 years or more (Garlich-Miller and Stewart 1999, p. 
188). The age of sexual maturity and birth rates may be density-
dependent (Fay et al. 1989, pp. 1-16; Fay et al. 1997, pp. 537-565; 
Garlich-Miller et al. 2006, pp. 892-893).
    The low birth rate of walruses is offset in part by considerable 
maternal investment in offspring (Fay et al. 1997, p. 550). Assumed 
survival rates through the first year of life range from 0.5 to 0.9 
(Fay et al. 1997, p. 550). Survival rates for juveniles through adults 
(i.e., 4-20 years old) have been assumed to be as high as 0.96 to 0.99 
per cent (DeMaster 1984, p. 78; Fay et al. 1997, p. 544), declining to 
zero by 40 to 45 years (Chivers 1999, p. 240). Using published 
estimates of survival and reproduction, Chivers (1999, pp. 239-247) 
developed an individual age-based model of the Pacific walrus 
population, which yielded a maximum population growth rate of 8 
percent, but cautioned this should not be considered to be an estimate 
of the maximum growth rate (Chivers 1999, p. 239). Thus, the 8 percent 
figure remains theoretical because age-specific survival rates for 
free-ranging walruses are poorly known.
Abundance
    Based on large sustained harvests in the 18th and 19th centuries, 
Fay (1982, p. 241) speculated that the pre-

[[Page 7639]]

exploitation population was represented by a minimum of 200,000 
animals. Since that time, population size is believed to have 
fluctuated in response to varying levels of human exploitation. Large-
scale commercial harvests are believed to have reduced the population 
to 50,000-100,000 animals in the mid-1950s (Fay et al. 1997, p. 539). 
The population apparently increased rapidly in size during the 1960s 
and 1970s in response to harvest regulations that limited the take of 
females (Fay et al. 1989, p. 4). Between 1975 and 1990, visual aerial 
surveys jointly conducted by the United States and Russia at 5-year 
intervals produced population estimates ranging from 201,039 to 
290,000. Efforts to survey the Pacific walrus population were suspended 
by both countries after 1990, due to unresolved problems with survey 
methods that produced population estimates with unknown bias and 
unknown--but presumably large--variances that severely limited their 
utility (Speckman et al. 2010, p. 3).
    In 2006, a joint U.S.-Russian survey was conducted in the pack ice 
of the Bering Sea, using thermal imaging systems to detect walruses 
hauled out on sea ice and satellite transmitters to account for 
walruses in the water (Speckman et al. 2010, p. 4). The number of 
walruses within the surveyed area was estimated at 129,000, with 95-
percent confidence intervals of 55,000 to 507,000 individuals. This is 
a minimum estimate, as weather conditions forced termination of the 
survey before much of the southwest Bering Sea was surveyed; animals 
were observed in that region as the surveyors returned to Anchorage, 
Alaska. Table 1 provides a summary of survey results.

                                            Table 1--Estimates of Pacific Walrus Population Size, 1975-2006.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Population size (with range
                  Year                    or confidence interval) \a\                                      Reference
--------------------------------------------------------------------------------------------------------------------------------------------------------
1975...................................                       214,687  (Udevitz et al. 2001, p. 614).
1980...................................               250,000-290,000  (Johnson et al. 1982, p. 3; Fedoseev 1984, p. 58).
1985...................................                       242,366  (Udevitz et al. 2001, p. 614).
1990...................................                       201,039  (Gilbert et al. 1992, p. 28).
2006...................................      129,000 (50,000-500,000)  (Speckman et al. 2010).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\Due to differences in methods, comparisons of estimates across years (population trends) are not possible. Most estimates did not provide a range or
  confidence interval.

    We acknowledge that these survey results suggest to some that the 
walrus population may be declining; however, we do not believe the 
survey methodologies support such a definitive conclusion. Resource 
managers in Russia have concluded that the population has declined, and 
accordingly, have reduced harvest quotas in recent years (Kochnev 2004, 
p. 284; Kochnev 2005, p. 4; Kochnev, 2010, pers. comm.), based in part 
on the lower abundance estimate generated from the 2006 survey results. 
However, past survey results are not directly comparable among years 
due to differences in survey methods, timing of surveys, segments of 
the population surveyed, and incomplete coverage of areas where 
walruses may have been present (Fay et al. 1997, p. 537); thus, these 
results do not provide a basis for determining trends in population 
size (Hills and Gilbert 1994, p. 203; Gilbert 1999, pp. 75-84). Whether 
prior estimates are biased low or high is unknown, because of problems 
with detecting individual animals on ice or land, and in open water, 
and difficulties counting animals in large, dense groups (Speckman et 
al. 2010, p. 33). In addition, no survey has ever been completed within 
a timeframe that could account for the redistribution of individuals 
(leading to double counting or undercounting), or before weather 
conditions either delayed the effort or completely terminated the 
survey before the entire area of potentially occupied habitat had been 
covered (Speckman et al. 2010). Due to these general problems, as well 
as seasonal differences among surveys (fall or spring) and 
technological advancements that correct for some problems, we do not 
believe the survey results provide a reliable basis for estimating a 
population trend.
    Changes in the walrus population have also been investigated by 
examining changes in biological parameters over time. Based on evidence 
of changes in abundance, distributions, condition indices, and life-
history parameters, Fay et al. (1989, pp.1-16) and Fay et al. (1997, 
pp. 537-565) concluded that the Pacific walrus population increased 
greatly in size during the 1960s and 1970s, and postulated that the 
population was approaching, or had exceeded, the carrying capacity of 
its environment by the early 1980s. Harvest increased in the 1980s: 
changes in the size, composition, and productivity of the sampled 
walrus harvest in the Bering Strait Region of Alaska over this time 
frame are consistent with this hypothesis (Garlich-Miller et al. 2006, 
p. 892). Harvest levels declined sharply in the early 1990s, and 
increased reproductive rates and earlier maturation in females 
occurred, suggesting that density-dependent regulatory mechanisms had 
been relaxed and the population was likely below carrying capacity 
(Garlich-Miller et al. 2006, p. 893). However, Garlich-Miller et al. 
(2006, pp. 892-893) also noted that there are no data concerning the 
trend in abundance of the walrus population or the status of its prey 
to verify this hypothesis, and that whether density-dependent changes 
in life-history parameters might have been mediated by changes in 
population abundance or changes in the carrying capacity of the 
environment is unknown.

Summary of Information Pertaining to the Five Factors

    Section 4 of the Act (16 U.S.C. 1533) and implementing regulations 
(50 CFR part 424) set forth the 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, we considered and evaluated the 
best available scientific and commercial information. Information 
pertaining to the Pacific walrus in relation to the five

[[Page 7640]]

factors provided in section 4(a)(1) of the Act is discussed below.
    In considering what factors might constitute threats to a species, 
we must look beyond the exposure of the species to a particular 
stressor to evaluate whether the species may respond to that stressor 
in a way that causes actual impacts to the species. If there is 
exposure to a stressor and the species responds negatively, the 
stressor may be a threat and we attempt to determine how significant a 
threat it is. The threat is significant if it drives, or contributes 
to, the risk of extinction of the species such that the species 
warrants listing as endangered or threatened as those terms are defined 
in the Act. However, the identification of stressors that could impact 
a species negatively may not be sufficient to compel a finding that the 
species warrants listing. The information must include evidence 
sufficient to suggest that these stressors are operative threats that 
act on the species to the point that the species meets the definition 
of endangered or threatened under the Act. Also, because an individual 
stressor may not be a threat by itself, but could be in conjunction 
with one or more other stressors, our process includes considering the 
combined effects of stressors.
    To inform our analysis of threats to the Pacific walrus, we also 
took into consideration the results of two Bayesian network modeling 
efforts; one conducted by the Service (Garlich-Miller et al. 2011), and 
the other conducted by the U.S. Geological Survey (USGS) (Jay et al. 
2010b). Although quantitative, empirical data can be used in Bayesian 
networks, when primarily qualitative data are available, such as for 
the Pacific walrus, the models are well suited to formalizing and 
quantifying the opinions of experts (Marcot et al. 2006, p. 3063). 
Bayesian network models (also known as Bayesian belief networks, 
reflecting the importance of expert opinion) graphically display the 
relevant stressors, the interactions among stressors, and the 
cumulative impact of those stressors as they are integrated through the 
network. In general terms, the network is composed of input variables 
that represent key environmental correlates (e.g., sea-ice loss, 
harvest, shipping) and response variables, (e.g., population status). 
Although we did not rely on the results of the Bayesian models as the 
sole basis for our conclusions in this finding, the models corroborated 
the results of our threats analysis. Results of the models are 
presented in the five-factor analysis below, where pertinent.

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

    The following potential stressors that may affect the habitat or 
range of the Pacific walrus are discussed in this section: (1) Loss of 
sea ice due to climate change; and (2) effects on prey species due to 
ocean warming and ocean acidification.
Effects of Global Climate Change on Sea-Ice Habitats
    The Pacific walrus depends on sea ice for several aspects of its 
life history. This section describes recent observations and future 
projections of sea-ice conditions in the Bering and Chukchi Seas 
through the end of the 21st century. Following this presentation on the 
changing ice dynamics, we examine how these changing ice conditions may 
affect the Pacific walrus population.
    The Arctic Ocean is covered primarily by a mix of multi-year sea 
ice, whereas more southerly regions, such as the Bering Sea, are 
seasonal ice zones where first-year ice is renewed every winter. The 
observed and projected effects of global warming vary in different 
parts of the world, and the Arctic and Antarctic regions are 
increasingly recognized as being extremely vulnerable to current and 
projected effects. For several decades, the surface air temperatures in 
the Arctic have warmed at approximately twice the global rate 
(Christensen et al. 2007, p. 904). The observed and projected effects 
of climate change are most extreme during summer in northern high-
latitude regions, in large part due to the ice-albedo (reflective 
property) feedback mechanism, in which melting of snow and sea ice 
lowers surface reflectivity, thereby further increasing surface warming 
from absorption of solar radiation.
    Since 1979 (the beginning of the satellite record of sea-ice 
conditions), there has been an overall reduction in the extent of 
Arctic sea ice (Parkinson et al. 1999, p. 20837; Comiso 2002, p. 1956; 
Stroeve et al. 2005, pp. 1-4; Comiso 2006, pp. 1-3; Meier et al. 2007, 
p. 428; Stroeve et al. 2007, p. 1; Comiso et al. 2008, p. 1; Stroeve et 
al. 2008, p. 13). Although the decline is a year-round trend, far 
greater reductions have been noted in summer sea ice than in winter sea 
ice. For example, from 1979 to 2009, the extent of September sea ice 
seen Arctic wide has declined 11 percent per decade (Polyak et al. 
2010, p. 1797). In recent years, the trend in Arctic sea-ice loss has 
accelerated (Comiso et al. 2008, p. 1). In September 2007, the extent 
of Arctic Ocean sea ice reached a record low, approximately 50 percent 
lower than conditions in the 1950s through the 1970s, and 23 percent 
below the previous record set in 2005 (Stroeve et al. 2008, p. 13). 
Minimum sea-ice extent in 2010 was the third lowest in the satellite 
record, behind 2007 and 2008 (second lowest), and most of this loss 
occurred on the Pacific side of the Arctic Ocean.
    Of long-term significance is the loss of over 40 percent of Arctic 
multi-year sea ice over the last 5 years (Kwok et al. 2009, p. 1). 
Since 2004, there has been a reversal in the volumetric and areal 
contributions between first-year ice and multi-year ice in regards to 
the total volume and area of the Arctic Ocean that they cover, with 
first-year ice now predominating (Kwok et al. 2009, p. 16). Export of 
ice through Fram Strait, together with the decline in multi-year ice 
coverage, suggests that recently there has been near-zero replenishment 
of multi-year ice (Kwok et al. 2009, p. 16). The area of the Arctic 
Ocean covered by ice predominantly older than 5 years decreased by 56 
percent between 1982 and 2007 (Polyak et al. 2010, p. 1759). Within the 
central Arctic Ocean, old ice has declined by 88 percent, and ice that 
is at least 9 years old has essentially disappeared (Markus et al. 
2009, p. 13: Polyak et al. 2010, p. 1759). In addition, from 2005 to 
2008 there was a thinning of 0.6 m (1.9 ft) in multi-year ice 
thickness. It is likely that the rapid decline of sea ice in 2007 was 
in part the result of thinner and lower coverage, of the multi-year ice 
(Comiso et al. 2008, p. 6). It would take many years to restore the ice 
thickness through annual growth, and the loss of multi-year ice makes 
it unlikely that the age and thickness composition of the ice pack will 
return to previous climatological conditions with continued global 
warming. Further loss of sea ice will be a major driver of changes 
across the Arctic over the next decades, especially in late summer and 
autumn (NOAA 2010, p. 77503).
    Due to asymmetric geography of the Arctic and the scale of weather 
patterns, there is considerable regional variability in sea-ice cover 
(Meier et al. 2007, p. 430), and although the early loss of summer sea 
ice and volumetric ice loss in the Arctic applies directly to the 
Chukchi Sea, it cannot be directly extrapolated to the seasonal ice 
zone of the Bering Sea (NOAA 2010, p. 77503). The contrasts between the 
two are dramatic: The Bering Sea is one of the most stable in terms of 
sea ice, especially in the winter, and the Chukchi Sea has had some of 
the most dramatic losses of summer sea ice

[[Page 7641]]

(Meier et al., p. 431). Below, we describe the sea-ice conditions in 
the Bering and Chukchi Seas as they occur presently, as well as recent 
trends and projections for the future.
    In March and April, at maximal sea-ice extent, the Chukchi Sea is 
typically completely frozen, and ice cover in the Bering Sea extends 
southward to a latitude of approximately 58-60 degrees north (Boveng et 
al. 2008, pp. 33-52). The Bering Sea spans the marginal sea-ice zone, 
where ice gives way to water at the southern edge, and around the 
peripheries of persistent polynyas. Sea ice in the Bering Sea is highly 
dynamic and largely a wind-driven system (Sasaki and Minobe 2005, pp. 
1-2). Ice cover is comprised of a variety of first-year ice 
thicknesses, from young, very thin ice to first-year floes that may be 
upwards of 1.0-m (3.3-ft) thick (Burns et al. 1980, p. 100; Zhang et 
al. 2010, p. 1729). Depending on wind patterns, a variable (but 
relatively minor) fraction of ice that drifts south through the Bering 
Strait could be comprised of some thicker ice floes that originated in 
the Chukchi and Beaufort Seas (Kozo et al. 1987, pp. 193-195).
    Ice melt in the Bering Sea usually begins in late April and 
accelerates in May, with the edge of the ice moving northward until it 
passes through the Bering Strait, typically in June. The Bering Sea 
remains ice free for the duration of the summer. Ice continues to 
retreat northward through the Chukchi Sea until September, when minimal 
sea-ice extent is reached.
    Freeze-up begins in October, with the ice edge progressing 
southward across the Chukchi Sea. The ice edge usually reaches the 
Bering Strait in November and advances through the Strait in December. 
The ice edge continues to move southward across the Bering Sea until 
its maximal extent is reached in March. There is considerable year-to-
year variation in the timing and extent of ice retreat and formation 
(Boveng et al. 2008, p. 37; Douglas 2010, p. 19).
    Within various regions of the Arctic, there is substantial 
variation in the monthly trends of sea ice (Meier et al. 2007, p. 431). 
In the Bering Sea, statistically significant monthly reductions in the 
extent of sea ice over the period 1979-2005 were documented for March 
(-4.8 percent), October (-42.9 percent), and November (-20.3 percent), 
although the overall annual decline (-1.9 percent) is not statistically 
significant (Meier et al. 2007, p. 431). The Bering Sea declines were 
greatest in October and November, the period of early freeze-up. In the 
Chukchi Sea, statistically significant monthly reductions were also 
documented for 1979 to 2005 for May (-0.19 percent), June (-4.3 
percent), July (-6.7 percent), August (-15.4 percent), September (-26.3 
percent), October (-18.6 percent), and November (-8.0 percent): The 
overall annual reduction (-4.9 percent) is statistically significant 
(Meier et al. 2007, p. 431). In essence, the Chukchi Sea has shown 
declines in all months when it is not completely ice-covered, with 
greatest declines in months of maximal melt and early freeze-up 
(August, September, and October).
    During the period 1979-2006, the September sea-ice extent in the 
Chukchi Sea decreased by 26 percent per decade (Douglas 2010, p. 2). In 
recent years, sea ice typically has retreated from continental shelf 
regions of the Chukchi Sea in August or September, with open water 
conditions persisting over much of the continental shelf through late 
October. In contrast, during the preceding 20 years (1979-1998), broken 
sea-ice habitat persisted over continental shelf areas of the Chukchi 
Sea through the entire summer (Jay and Fischbach 2008, p. 1).
    From 1979 to 2007, there was a general trend toward earlier onset 
of ice melt and later onset of freeze-up in 9 of 10 Arctic regions 
analyzed by Markus et al. (2009, pp. 1-14), the exception being the Sea 
of Okhotsk. For the entire Arctic, the melt season length has increased 
by about 20 days over the last 30 years, due to the combined earlier 
melt and later freeze-up. The largest increases, of over 10 days per 
decade, have been seen for Hudson Bay, the East Greenland Sea, and the 
Laptev/East Siberian Seas. From 1979 to 2007, there was a general trend 
toward earlier onset of ice melt and later onset of freeze-up in both 
the Bering and Chukchi Seas: For the Bering Sea, the onset of ice melt 
occurred 1.0 day earlier per decade, while in the Chukchi/Beaufort Seas 
ice melt occurred 3.5 days earlier per decade. The onset of freeze-up 
in the Bering Sea occurred 1.0 day later per decade, while freeze-up in 
the Chukchi/Beaufort Seas occurred 6.9 days later per decade (Markus et 
al. 2009, p. 11).
    Later freeze-up in the Arctic does not necessarily mean that less 
seasonal sea ice forms by winter's end in the peripheral seas, such as 
the Bering and Chukchi Seas (Boveng et al. 2008, p. 35). For example, 
in 2007 (the year when the record minimal Arctic summer sea-ice extent 
was recorded), the Chukchi Sea did not freeze until early December and 
the Bering Sea remained largely ice-free until the middle of December 
(Boveng et al. 2008, p. 35). However, rapid cooling and advancing of 
sea ice in late December and early January resulted in most of the 
eastern Bering Sea shelf being ice-covered by mid-January, an advance 
of 900 km (559 mi), or 30 km per day (19 mi per day). Maximum ice 
extent occurred in late March, with ice covering much of the shelf, 
resulting in a near record maximum ice extent. Ice then slowly 
retreated, and the Bering Sea was not ice-free until almost July. 
Therefore, winter ice conditions are not necessarily related to the 
summer-fall ice conditions of the previous year.
Model Projections of Future Sea Ice
    The analysis and synthesis of information presented by the 
Intergovernmental Panel on Climate Change (IPCC) in its Fourth 
Assessment Report (AR4) in 2007 represents the scientific consensus 
view on the causes and future of climate change. The IPCC AR4 used 
state-of-the-art Atmosphere-Ocean General Circulation Models (GCMs) and 
a range of possible future greenhouse gas (GHG) emission scenarios to 
project plausible outcomes globally and regionally, including 
projections of temperature and Arctic sea-ice conditions through the 
21st century.
    The GCMs use the laws of physics to simulate the main components of 
the climate system (the atmosphere, ocean, land surface, and sea ice) 
and to make projections as to the response of these components to 
future emissions of GHGs. The IPCC used simulations from about 2 dozen 
GCMs developed by 17 international modeling centers as the basis for 
the AR4 (Randall et al. 2007, pp. 596-599). The GCM results are 
archived as part of the Coupled Model Intercomparison Project-Phase 3 
(CMIP3) at the Program for Climate Model Diagnosis and Intercomparison 
(PCMDI). The CMIP3 GCMs provide projections of future effects that 
could result from climate change, because they are built on well-known 
dynamical and physical principles, and they plausibly simulate many 
large-scale aspects of present-day conditions. However, the coarse 
resolution of most current climate models dictates careful application 
on smaller spatial scales in heterogeneous regions.
    The IPCC AR4 used six ``marker'' scenarios from the Special Report 
on Emissions Scenarios (SRES) (Carter et al. 2007, p. 160) to develop 
climate projections spanning a broad range of GHG emissions through the 
end of the 21st century under clearly stated assumptions about 
socioeconomic factors that could influence the emissions. The six 
``marker'' scenarios are classified according to their emissions as 
``high'' (A1F1, A2),

[[Page 7642]]

``medium'' (A1B and B2) and ``low'' (A1T, B1). The SRES made no 
judgment as to which of the scenarios were more likely to occur, and 
the scenarios were not assigned probabilities of occurrence (Carter et 
al. 2007, p. 160). The IPCC focused on three of the marker scenarios--
B1, A1B, and A2--for its synthesis of the climate modeling efforts, 
because they represented ``low,'' ``medium,'' and ``high,'' scenarios; 
this choice stemmed from the constraints of available computer 
resources that precluded realizations of all six scenarios by all 
modeling centers (Meehl et al. 2007, p. 753). With regard to these 
three emissions scenarios, the IPCC Working Group I report noted: 
``Qualitative conclusions derived from these three scenarios are in 
most cases also valid for other SRES scenarios'' (Meehl et al. 2007, p. 
761). It is important to note that the SRES scenarios do not contain 
additional climate initiatives (e.g., implementation of the United 
Nations Framework Convention on Climate Change or the emissions targets 
of the Kyoto Protocol) beyond current mitigation policies (IPCC 2007, 
p. 22). The SRES scenarios do, however, have built-in emissions 
reductions that are substantial, based on assumptions that a certain 
amount of technological change and reduction of emissions would occur 
in the absence of climate policies; recent analysis shows that two-
thirds or more of all the energy efficiency improvements and 
decarbonization of energy supply needed to stabilize GHGs is built into 
the IPCC reference scenarios (Pielke et al. 2008, p. 531).
    There are three main contributors to divergence in GCM climate 
projections: Large natural variations, across-model differences, and 
the range-in-emissions scenarios (Hawkins and Sutton 2009, p. 1096). 
The first of these, variability from natural variation, can be 
incorporated by averaging the projections over decades, or, preferably, 
by forming ensemble averages from several runs of the same model.
    The second source of variation is model to model differences in the 
way that physical processes are incorporated into the various GCMs. 
Because of these differences, projections of future climate conditions 
depend, to a certain extent, on the choice of GCMs used. Uncertainty in 
the amount of warming out to mid-century is primarily a function of 
these model-to-model differences. The most common approach to address 
the uncertainty and biases inherent in individual models is to use the 
median or mean outcome of several predictive models (a multi-model 
ensemble) for inference. Excluding models that poorly simulate 
observational data is also a common approach to reducing the spread of 
uncertainty among projections from multi-model ensembles.
    The third source of variation arises from the range in plausible 
GHG emissions scenarios. Conditions such as surface air temperature and 
sea-ice area are linked in the IPCC climate models to GHG emissions by 
the physics of radiation processes. When CO2 is added to the 
atmosphere, it has a long residence time and is only slowly removed by 
ocean absorption and other processes. Based on IPCC AR4 climate models, 
expected global warming--defined as the change in global mean surface 
air temperature (SAT)--by the year 2100 depends strongly on the assumed 
emissions of CO2 and other GHGs. By contrast, warming out to 
about 2040-2050 will be largely due to emissions that have already 
occurred and those that will occur over the next decade (Meehl 2007, p. 
749). Thus, conditions projected to mid-century are less sensitive to 
assumed future emission scenarios. For the second half of the 21st 
century, however, and especially by 2100, the choice of the emission 
scenario becomes the major source of variation among climate 
projections and dominates over natural variability and model-to-model 
differences (IPCC 2007, pp. 44-46).
    Because the SRES group and the IPCC made no judgment on the 
likelihood of any of the scenarios, and the scenarios were not assigned 
probabilities of occurrence, one option for representing the full range 
of variability in potential outcomes, would be to evaluate projections 
from all models under all marker scenarios for which sea-ice 
projections are available to the scientific community--A2, A1B, and B1. 
Another typical procedure for projecting future outcomes is to use an 
intermediate scenario, such as A1B, to predict changes, or one 
intermediate and one high scenario (e.g., A1B and A2) to capture a 
range of variability.
    Several factors suggest that the A1B scenario may be a particularly 
appropriate choice of scenario to use for projections of sea-ice 
declines in the Arctic and its marginal seas. First, the A1B scenario 
is widely used in modeling because it is a ``medium'' emissions 
scenario characterized by a future world of very rapid economic growth, 
global population that peaks in mid-century and declines thereafter, 
rapid introduction of new and more efficient technologies, and 
development of energy technologies that are balanced across energy 
sources, and it contains no assumption of mitigation policies that may 
or not be realized. Thus, there are a number of studies in the 
published sea-ice literature that use the A1B scenario and can, 
therefore, be used for comparative purposes (e.g., Overland and Wang 
2007; Holland et al. 2010; Wang et al. 2010). Second, both the A1B and 
A2 scenarios project similar declines in hemispheric sea-ice extent out 
to 2100 (Meehl et al. 2007, Figure 10.13, p. 771); thus, little new 
understanding is gained by using projections from both scenarios (see 
discussion of Douglas 2010 in subsequent paragraphs). Third, model 
projections based on the B1 scenario appear to be overly conservative 
(Meehl et al. 2007, Figure 10.13, p. 771), in that sea ice is declining 
even faster than the decline forecasted by the A1B scenario (see 
discussion at end of this section). Fourth, current global carbon 
emissions appear to be tracking slightly above (Raupach et al. 2007, 
Figure 1, p. 10289; LeQuere et al. 2009, Figure 1a, p. 2; Global Carbon 
Project 2010 at http://www.globalcarbonproject.org/carbonbudget/09/files/GCP2010_CarbonBudget2009_29November2010.pdf) or slightly below 
(Manning et al. 2010, Figure 1, p. 377) the A1B trajectory at this 
point in time. It may be reasonable to project this or a higher trend 
in global carbon emissions into the near future (Garnaut et al. 2008, 
Figure 5, p. 392; Sheehan 2008, Figure 2, p. 220; but see caveat by van 
Vuuren et al. 2010). Fifth, there is a growing body of opinion that 
stabilizing GHG emissions at levels well below the A1B scenario (e.g., 
at 450 parts per million (ppm), equivalent to a 2 degree Celsius 
increase in temperature) will be difficult in the absence of 
substantial policy-mandated mitigation (e.g., Garnaut et al. 2007, p. 
398; den Elzen and H[ouml]hne 2008, p. 250; Pielke et al. 2008, pp. 
531-532; Macintosh 2009, p. 3; den Elzen et al. 2010, p. 314; Tomassini 
et al. 2010, p. 418; Anderson and Bows 2011, p. 20), largely as a 
result of continuing high emissions in certain developed countries, and 
recent and projected growth in the economies and energy demands of 
rapidly developing countries (e.g., Garnaut et al. 2008, p. 392; 
Auffhammer and Carson 2008, p. 1; Pielke et al. 2008, p. 532; U.S. 
Energy Information Administration 2010, pp. 123-124, 128). Because of 
these factors, we conclude that sea-ice projections developed by using 
the A1B forcing scenario provide an appropriate basis for evaluating 
potential impacts to habitat and related impacts to the Pacific walrus 
population in the future.
    Our analysis of sea-ice response to global warming within the range 
of the

[[Page 7643]]

Pacific walrus (Bering and Chukchi Seas) carefully considered the 
synthesis of GCM projections presented by Douglas (2010). We provide a 
broad overview of the methods and findings of the report by Douglas 
(2010), details of which are available in the full report.
    Douglas (2010, pp. 4-5) quantified sea-ice projections (from the A2 
and A1B scenarios) by 18 CMIP3 GCM models prepared for the IPCC fourth 
reporting period, as well as 2 GCM subsets which excluded models that 
poorly simulated the 1979-2008 satellite record of Bering and Chukchi 
sea-ice conditions. Analyses focused on the annual cycle of sea-ice 
extent within the range of the Pacific walrus population, specifically 
the continental shelf waters of the Bering and Chukchi Seas. Models 
were selected for the two subsets, respectively, when their simulated 
mean ice extent and seasonality during 1979-2008 were within two 
standard deviations (SD2) and one standard deviation (SD1) of the 
observed means. In consideration of observations of ice-free conditions 
across the Chukchi Sea in recent years in late summer, any models that 
failed to simulate at least 1 ice-free month in the Chukchi Sea were 
also excluded from the Chukchi Sea subset ensembles. Ice observations 
and the projections of individual GCMs were pooled over 10-year periods 
to integrate natural variability (Douglas 2010, p. 5).
    To quantify projected changes in monthly sea-ice extent, Douglas 
(2010, p. 31) compared future monthly sea-ice projections for the 
Bering and Chukchi Seas at mid-century (2045-2054) and late-century 
(2090-2099) with two decades from the observational record (1979-1988 
and 1999-2008). The earliest observational period (1979-1988), which 
coincides with a timeframe during which the Pacific walrus population 
was considered to be occupying most of its historical range (Fay 1982, 
pp. 7-21), provides a useful baseline for examining projected changes 
in sea-ice habitats.
    Douglas (2010, p. 7) found that projected median sea-ice extents 
under both the A1B and A2 forcing scenarios are qualitatively similar 
in the Bering and Chukchi Seas in all seasons throughout the 21st 
century. This finding is consistent with the generally similar declines 
in hemispheric sea-ice extent between the A1B and A2 scenarios out to 
2100 (Meehl et al. 2007, Figure 10.13, p. 771). Thus, our decision to 
focus on ice projections by the A1B forcing scenario (as described 
above) is further substantiated, as there would be little insight 
gained by considering the A2 scenario.
    The analysis of Douglas (2010, pp. 24, 31) yields mid-century 
projections that indicate sea-ice extent in the Bering Sea will decline 
for all months when sea ice has historically been present, i.e., for 
October through June. The most pronounced reductions in Bering Sea ice 
extent at mid-century in terms of the percent change from baseline 
conditions are expected in the months of June and November, which 
reflects an increasingly early onset of ice-free or nearly ice-free 
conditions in the early summer and later onset of sea-ice development 
in the fall. In June, the projected extent of sea ice is -63 percent of 
the 1979-1988 baseline level, while the projected extent for November 
is approximately is -88 percent of the baseline level. By late century, 
substantial declines in Bering Sea ice extent are projected for all 
months, with losses ranging from 57 percent in April, to 100 percent 
loss of sea ice in November (Douglas 2010, p. 31). The onset of 
substantial freezing in the Bering Sea is projected to be delayed until 
January by late century, with little or no ice projected to remain in 
May by the end of the century (Douglas 2010, pp. 8, 24, 31).
    Historically, sea-ice cover has persisted, to at least some extent, 
over continental shelf waters of the Chukchi Sea all 12 months of the 
year, although the extent of sea ice has varied by month. For example, 
for the 1979-1988 period, the median extent of sea ice varied from 
about 50 percent in September to essentially 100 percent from late 
November through early May (Douglas 2010, p. 19). A pattern of 
extensive sea-ice cover (approaching 100 percent) in late winter and 
early spring (February-April) is expected to persist through the end of 
the century.
    Projections of sea-ice loss during June in the Chukchi Sea are 
relatively modest; however, the sea ice is projected to retreat rapidly 
during the month of July (Douglas 2010, p. 12). Model subset medians 
project a 2-month ice-free season at mid-century and a 4-month ice-free 
season at the end of the century, centered around the month of 
September (Douglas 2010, pp. 8, 22, 24), with some models showing up to 
5 months ice-free by end of the century (Douglas 2010, pp. 12, 22, 24). 
In the most recent observational decade (1999-2008), the southern 
extent of the Arctic ice pack has retreated and advanced through the 
Bering Strait in the months of June and November, respectively. By the 
end of the century, these transition months may shift to May (1 month 
earlier) and January (2 months later), respectively (Douglas 2010, pp. 
12, 25-26).
    The projected loss of sea ice involves uncertainty. In discussing 
this, Douglas 2010 (p. 11) states, in part: ``Ice-free conditions in 
the Chukchi Sea are attained for a 3-month period (August-October) at 
the end of the century (fig 7) with almost complete agreement among 
models of the SD2 subset (fig 12). Consequently, a higher degree of 
confidence can accompany hypotheses or decisions premised on this 
outcome and timeframe.'' Douglas also notes there is greater confidence 
in projections that the Chukchi Sea will continue to be completely ice 
covered during February-April at the end of century, and that large 
uncertainties are prevalent during the melt and freeze seasons, 
particularly June, November, and December (Douglas 2010, p. 11).
    Several other investigations have analyzed model projections of 
sea-ice change in the Bering and Chukchi Seas and reported results that 
are consistent with those of Douglas (2010). Wang et al. (2010, p. 258) 
investigated sea-ice projections to mid-century for the Bering Sea 
using a subset of models selected on the basis of their ability to 
simulate sea-ice area in the late 20th century. Their projections show 
an average decrease in March-April sea-ice coverage of 43 percent by 
the decade centered on 2050, with a reasonable degree of consistency 
among models. Boveng et al. (2008, pp. 39-40) analyzed a subset of IPCC 
AR4 GCM models (selected for accuracy in simulating observed ice 
conditions) to evaluate spring (April-June) conditions in the Bering 
Sea out to 2050. Their analysis suggested that by mid-century, a modest 
decrease in the extent of sea ice in the Bering Sea is expected during 
the month of April, and that ice cover in May will remain variable, 
with some years having considerably reduced ice cover. June sea-ice 
cover in the Bering Sea since the 1970s has been consistently low or 
absent. Their models project that by 2050, ice cover in the Bering Sea 
will essentially disappear in June, with only a rare year when the ice 
cover exceeds 0.05 million sq km (0.03 million sq mi) (Boveng et al. 
2008, pp. 39-40), a projection similar to that reported by Douglas 
(2010, p. 24).
    Boveng et al. (2009, pp. 44-54) used a subset of IPCC AR4 models to 
further investigate sea-ice coverage in the eastern Bering Sea (the 
area of greatest walrus distribution in the Bering Sea), Bering Strait, 
and the Chukchi Sea out to 2070. For the eastern Bering Sea, they 
projected that sea-ice coverage will decline in the spring and fall, 
with fall declines exceeding those of spring. By 2050, average sea-ice 
extent in November and December would be

[[Page 7644]]

approximately 14 percent of the 1980-1999 mean, while sea-ice extent 
from March to May would be about 70 percent of the 1980-1999 mean. For 
the Bering Strait region, the model projections indicated a longer ice-
free period by 2050, largely as a result of decreasing ice coverage in 
November and December. By 2050, they project that the March-May sea-ice 
extent in the Bering Strait region would be 80 percent of the 1980-1999 
mean, while November ice extent would be 20 percent of the mean for 
that reference period. For the Chukchi Sea, Boveng et al. (2009, pp. 
49-50) reported a projected reduction in sea-ice extent for November by 
2050, a slight decline for June by 2070, and a clear reduction for 
November and December by 2070.
    Several authors note that sea-ice extent in the Arctic is 
decreasing at a rate faster than projected by most IPCC-recognized GCMs 
(Stroeve et al. 2007, p. 1; Overland and Wang 2007, p. 1; Wang and 
Overland 2009, p. 1; Wang et al. 2010, p. 258), suggesting that GCM 
projections of 21st century sea-ice losses may be conservative (Douglas 
2010, p. 11, and citations therein) and that ice-free conditions in 
September in the Arctic may likely be achieved sooner than projected by 
most models using the A1B forcing scenario. In describing the ``faster 
than forecast'' situation, Douglas notes that the minimum ice extents 
in the Arctic for the summers of 2007-2009 were well below the previous 
record set in 2005, and concurs that serious consideration must be 
given to the possibility that the CMIP3 GCM projections collectively 
yield conservative time frames for sea-ice losses in this century 
(Douglas 2010, p. 11); i.e., the projected changes he reports for the 
range of the Pacific walrus may occur sooner than the model projections 
indicate.
    In conclusion, the actual loss of sea ice in recent years in the 
Arctic has been faster than previously forecast, current GHG emissions 
are at or above those expected under the A1B scenario that we (and most 
scientists studying Arctic sea ice) relied on, models converge in 
predicting the extended absence of sea ice in the Chukchi Sea at the 
end of the century (Douglas 2010, pp. 12, 29), and there has been a 
marked loss of sea ice over the Chukchi Sea in the past decade. The 
best scientific information available gives us a high level of 
confidence that despite some uncertainty among the models, the 
projections are generally consistent and provide a reliable basis for 
us to conclude that sea-ice loss in the range of the Pacific walrus has 
a high likelihood of continuing.
Effects of Changing Sea-Ice Conditions on Pacific Walruses
    The Pacific walrus is an ice-dependent species. Walruses are poorly 
adapted to life in the open ocean and must periodically haul out to 
rest. Floating pack ice creates habitat from which breeding behavior is 
staged (Fay et al. 1984, p. 81), and it provides a platform for calving 
(Fay 1982, p. 199), access to offshore feeding areas over the 
continental shelf of the Bering and Chukchi Seas, passive 
transportation among feeding areas (Ray et al. 2006, pp. 404-407), and 
isolation from terrestrial predators and hunters. In this section, we 
first analyze the effects of sea-ice loss on breeding and calving, 
because these are essential life-history events that depend on ice in 
specific seasons. In the second part of this section, we analyze how 
the anticipated increasing use of coastal haulouts due to the loss of 
sea-ice habitat may cause localized prey depletion and affect walrus 
foraging, as well as increase their susceptibility to trampling, 
predation, and hunting.
Effects of Sea-Ice Loss on Breeding and Calving
Breeding
    During the January-to-March breeding season, walruses congregate in 
the Bering Sea pack ice (Fay 1982, pp. 8-11, 193; Fay et al. 1984, pp. 
89-99), where the ice creates the stage for breeding. Females 
congregate in herds on the ice and the bulls station themselves in the 
water alongside the herd and perform visual and acoustical displays 
(Fay 1982, p. 193). Breeding aggregations have been reported southwest 
of St. Lawrence Island, Alaska, south of Nunivak Island, Alaska, and 
south of the Chukotka Peninsula in the Gulf of Anadyr, Russia (Fay 
1982, p. 21; Mymrin et al. 1990, pp. 105-113). It is unlikely that 
breeding is tied to a specific geographic location, because of the 
large seasonal and inter-annual variability in sea-ice cover in the 
Bering Sea at this time of year. Fay et al. (1984, p. 80) indicate 
probable changes in the locations of breeding aggregations based on 
differing amounts of sea ice. We anticipate that seasonal pack ice will 
continue to form across large areas of the northern Bering Sea, 
primarily in January-March, and will persist in most years through 
April (Douglas 2010, p. 25).
    The distribution of walruses during the winter breeding season will 
likely shift in the future in response to changing patterns of sea-ice 
development. Core areas of winter abundance south of Saint Lawrence 
Island and the Gulf of Anadyr will likely continue to have adequate ice 
cover to support breeding aggregations through mid-century, as the 
extent of sea ice will still be relatively substantial, although 
slightly diminished from the current extent (Douglas 2010, p. 25). 
Walruses currently wintering in Northern Bristol Bay will likely shift 
their distribution northward in response to the projected loss of 
seasonal pack ice in this region (Douglas 2010, p. 25). By the end of 
the century, winter sea-ice extent across the Bering Sea is expected to 
be greatly reduced, and the median sea-ice edge is projected to be 
farther to the north (Douglas 2010, p. 25). Based on these projections, 
core areas of winter abundance and breeding aggregations will likely 
shift farther north. Potentially, the breeding aggregations may shift 
into areas north of the Bering Strait in the southern Chukchi Sea in 
some years by the end of the century (Douglas 2010, pp. 24, 28).
    Although the location of winter breeding aggregations will likely 
shift in response to projected reductions in sea-ice extent, sea-ice 
platforms for herds of females will persist during the breeding season; 
therefore, we conclude that suitable conditions for breeding will 
likely persist into the foreseeable future. We have no information that 
indicates that the specific location of the ice is important, and sea 
ice is expected to remain over shallow, food-rich areas. Therefore, we 
do not consider changes in sea-ice extent during the winter breeding 
season to be a threat now or in the foreseeable future.
Calving
    Female walruses typically give birth to a single calf in May on sea 
ice, shortly before or during the northward spring migration through 
the Bering Strait. By mid-century, ice extent in the Bering Strait 
Region is projected to be reduced during the May calving season, and by 
end of century, the Bering Sea is projected to be largely sea-ice-free 
during the month of May (Douglas 2010, p. 25). As is the case with 
breeding, the birth of a calf and the natal period in the weeks that 
follow are probably not tied to specific geographic locations. It is 
reasonable to assume that suitable ice conditions for calving and post-
calving activity on sea ice will persist into the foreseeable future, 
even though the location of favorable ice conditions is likely to shift 
further to the north over time.
    We conclude that changes in sea ice during the spring calving 
season (April-May) are not a threat now or in the foreseeable future. 
We have no

[[Page 7645]]

information that indicates the specific location of the ice is 
important, and sea ice would remain over shallow, food-rich areas.
Summary of Effects of Sea-Ice Loss on Breeding and Calving
    Breeding and calving activities utilize ice as a platform in the 
months of January through May. Based on our current understanding of 
these activities, the specific location of the ice is not important. 
Although sea-ice extent is projected to move northward over time, sea 
ice is expected to persist in these months and be available for these 
life history functions. Therefore, we do not consider changes in sea-
ice extent to be a threat to breeding or calving activities now or in 
the foreseeable future.
Effects of Increasing Dependence on Coastal Haulouts Due to Sea-Ice 
Loss
    We begin this discussion with a summary of sea-ice loss projections 
and recent observations. We follow with an analysis of the potential 
effects to Pacific walrus from an increasing dependence on coastal 
haulouts, particularly in the Chukchi Sea, and examine the use of 
coastal haulouts by Atlantic walrus as a potential analog for Pacific 
walrus coastal haulout use. We analyze potential effects of increased 
dependency on coastal haulouts resulting from the loss of sea-ice 
habitats. Some of the effects to Pacific walrus that we have identified 
as a result of increasing dependence on coastal haulouts (i.e., 
trampling, predation, and hunting) would typically be discussed under 
other Factors. These effects are discussed in this section in the 
context of responses to declining sea ice; however, it should be noted 
that we also discuss predation under Factor C (Disease or Predation), 
and hunting under Factor B (Overutilization for Commercial, 
Recreational, Scientific, or Educational Purposes) and Factor D (The 
Inadequacy of Existing Regulatory Mechanisms).
Summary of Sea-Ice Loss Projections
    Sea ice has historically persisted over continental shelf regions 
of the Chukchi Sea through the entire melt season. Over the past 
decade, sea ice has begun to retreat beyond shallow continental shelf 
waters in late summer. The recent trend of rapid ice loss from 
continental shelf regions of the Chukchi Sea in July and August is 
projected to persist, and will likely accelerate in the future (Douglas 
2010, p. 12). The onset of ice formation in the fall over continental 
shelf regions in the Chukchi and Bering Seas is expected to be delayed, 
and by mid-century (2045-2054), ice-free conditions over most 
continental shelf regions of the Chukchi Sea are projected to persist 
for 2 months (August-September). By late century, ice-free (or nearly 
sea-ice-free) conditions may persist for 3 months, and extend to 4 to 5 
months in some years (Douglas 2010, pp. 8, 12, 22, 27). The average 
number of ice-free months in the Bering Sea is projected to increase 
from the approximately 5.5 months currently, to approximately 6.5 and 
8.5 months at mid- and end of century, respectively (Douglas 2010, pp. 
12, 27).
Observed and Expected Responses of Pacific Walruses to Declining Sea-
Ice Habitats
    Adult male walruses make greater use of coastal haulouts during 
ice-free seasons than do females and dependent young, and consequently, 
have a broader distribution during ice-free seasons. Several thousand 
bulls remain in the Bering Sea through the ice-free summer months, 
where they make foraging excursions from coastal haulouts in Bristol 
Bay, Alaska and the Gulf of Anadyr, Russia. The size of these haulouts 
has changed over time; for example, at Round Island, the number of 
hauled out walruses grew from about 3,000 animals in the late 1950s to 
about 12,000 in the early 1980s (Jay and Hills 2005, p. 193), and has 
subsequently declined to 2,000-5,000 animals in the past decade (Sell 
and Weiss 2010, p. 12). The reasons for changes in walrus haulout use 
in the Bering Sea are poorly understood. Factors that could affect use 
of haulouts include; prey abundance and distribution, walrus density, 
and physical alteration or chronic disturbance at the haulouts (Jay and 
Hills 2005, p. 198). Tagged males traveled up to 130 km (81 mi) to feed 
from haulout sites in Bristol Bay (Jay and Hills 2005, p. 198). Because 
the benthic densities are poorly documented, it is not possible to link 
the changes in haulout use by males to prey depletion. However, non-use 
of areas with shallow depths closer to the haulouts suggests prey was 
not adequate for effective foraging (Jay and Hills 2005, p. 198). Males 
have an advantage over females in that they are bigger and stronger and 
have no responsibilities related to the care of calves, and thus, can 
travel as far as necessary to locate food. Currently, males utilize 
terrestrial haulouts for 5 months or more (Jay and Hills 2005, p. 198). 
It is unlikely that the projected increase in ice-free months in the 
Bering Sea will alter male behavior or survival rates at terrestrial 
haulouts because the adult males that utilize Bering Sea haulouts do 
not rely on sea ice as a foraging platform. Indirect effects of global 
climate change on walrus prey species in this region are considered 
separately below in the section: Effects of Global Climate Change on 
Pacific Walrus Prey Species.
    Most of the Pacific walrus population (adult females, calves, 
juveniles, and males that have not remained at coastal haulouts in the 
Bering Sea) migrate northward in spring following the retreating pack 
ice through the Bering Strait to summer feeding areas over the 
continental shelf in the Chukchi Sea. Historically, sufficient pack-ice 
habitat has persisted over continental shelf regions of the Chukchi Sea 
through the summer months such that walruses in the Chukchi Sea did not 
rely on coastal haulouts with great frequency or in large numbers. Over 
the past decade, however, sea ice has begun to retreat north beyond 
shallow continental shelf waters of the Chukchi Sea in late summer. 
This has caused walruses to relocate to coastal haulouts, which they 
use as sites for resting between foraging excursions. The number of 
walruses using land-based haulouts along the Chukchi Sea coast during 
the summer months, and the duration of haulout use, has increased 
substantially over the past decade, with up to several tens of 
thousands of animals hauling out at some locations along the coast of 
Russia during ice-free periods (Ovsyanikov et al. 2007, pp. 1-2; 
Kochnev 2008, p. 17-20, Kavry et al. 2008, p. 248-251). Coastal 
haulouts have also begun to form along the Arctic coast of Alaska in 
recent years (2007, 2009, and 2010) when sea ice retreated north of the 
continental shelf in late summer (Service 2010, unpublished data). The 
occupation of terrestrial haulouts along the Chukchi Sea coast for 
extended periods of time in late summer and fall represents a 
relatively new and significant change from traditional habitat use 
patterns. The consequences of this observed and projected shift in 
habitat use patterns is the primary focus of our analysis.
    As sea ice withdraws from offshore feeding areas over the 
continental shelf of the Chukchi Sea, walruses are expected to become 
increasingly dependent on coastal haulouts as a foraging base during 
the summer months. With a delay the onset of ice formation in the fall, 
and in the absence of sea-ice cover in the southern Chukchi Sea and 
northern Bering Sea in the summer, walruses will likely remain at 
coastal haulouts for longer periods of time until sea ice reforms in 
the fall or early winter. By the end of the century, dependence on 
Chukchi Sea coastal haulouts by mixed groups of walruses

[[Page 7646]]

for resting and as a foraging base may extend from July into early 
winter (December-January), when there may be up to a 2-month delay in 
freeze-up (Douglas 2010, pp. 12, 22). This expectation is consistent 
with observations made by Russian scientists that some of the coastal 
haulouts along the southern Chukchi Sea coast of Russia have persisted 
in recent years into December (Kochnev 2010, pers. comm.).
    Increased dependence on coastal haulouts creates the following 
potential impacts for walruses: Changes in foraging patterns and prey 
depletion; increased vulnerability to mortality or injury due to 
trampling, especially for calves, juveniles, and females; greater 
vulnerability to mortality or injury from predation; and greater 
vulnerability to mortality due to hunting. Each is discussed in detail 
below.
Changes in Foraging Patterns and Prey Depletion
    The loss of seasonal pack ice from continental shelf areas of the 
Chukchi Sea is expected to reduce access to traditional foraging areas 
across the continental shelf and increase competition among individuals 
for food resources in areas close to haulouts. Information regarding 
the density of walrus prey items accessible from coastal haulouts is 
limited; however, some haulouts have supported sizable concentrations 
of animals (up to several tens of thousands of animals) for periods of 
up to 4 months in recent years (Kochnev 2010, pers. comm.). Many walrus 
prey species are slow growing and potentially vulnerable to 
overexploitation, and intensive foraging from coastal haulouts by large 
numbers of walruses may eventually result in localized prey depletion 
(Ray et al. 2006, p. 412). A walrus requires approximately 29 to 74 kg 
(64 to 174 lbs) of food per day (Fay 1982, p. 160), and may consume 
4,000 to 6,000 clams in one feeding bout (Ray et al. 2006, pp. 408, 
412); therefore, when large numbers of walruses are concentrated on 
coastal haulouts, a large amount of prey (whether clams or other types 
of prey) must be available to support them.
    The presence of large numbers of walruses at a coastal haulout over 
an extended time period could eventually lead to localized prey 
depletion. The most likely response to localized prey depletion will be 
for walruses to seek out and colonize other terrestrial haulouts that 
have suitable foraging areas (Jay and Hills 2005, p. 198). However, 
prey densities along the Arctic coast are not uniform (Grebmeier et al. 
1989, p. 257; Feder et al. 1994, pp. 176-177; Grebmeier et al. 2006b, 
p. 346), and many coastal areas which provide the physical features of 
a suitable haulout, may not have sufficient food sources. A visual 
comparison of areas of high benthic production (e.g., Springer et al. 
1996, p. 209; Dunton et al. 2005, p. 3468; Grebmeier et al. 2006b, p. 
346) and areas that have supported large terrestrial haulouts of 
walruses (e.g., Cape Inkigur, Cape Serdtse-Kamen) indicates that 
walruses have historically selected sites near areas of very high 
benthic productivity. Benthic productivity along part of the western 
shore of Alaska (i.e., along the eastern edge of the Chukchi Sea) is 
low because of the nutrient-poor waters of the Alaska Coastal Current, 
especially for instance, in the Kotzebue Sound (Dunton et al. 2005, p. 
3468; Dunton et al. 2006, p. 369; Grebmeier et al. 2006b, p. 346). 
Consequently, the number of sites with adequate food resources to 
support large aggregations of walruses is likely limited.
    A consequence of prey depletion could be an increased energetic 
cost to locate sufficient food resources (Sheffield and Grebmeier 2009, 
p. 770; Jay et al. 2010b, pp. 9-10). Energetic costs to walruses will 
increase if they have to travel greater distances to locate prey, or 
foraging efficiency is reduced as a consequence of lower prey densities 
(Sheffield and Grebmeier 2009, p. 770; Jay et al. 2010b, pp. 9-10). 
Observations by Russian scientists at haulouts along the coast of 
Chukotka (along the western side of the Chukchi Sea) in recent years 
suggest that rates of calf mortality and poor body condition of adult 
females are inversely related to the persistence of sea ice over 
offshore feeding areas and the length of time that animals occupy 
coastal haulouts (Nikiforov et al. 2007, pp. 1-2; Ovsyanikov et al. 
2007, pp. 1-3; Kochnev 2008, pp. 17-20; Kochnev et al. 2008, p. 265). 
Over time, poor body condition could lead to lower reproductive rates, 
greater susceptibility to disease or predation, and ultimately higher 
mortality rates (Kochnev 2004, pp. 285-286; Kochnev et al. 2008, p. 
265; Sheffield and Grebmeier 2009, p. 770).
    The energetic cost of swimming a long distance is demonstrated by 
the observations made in the summer of 2007, when the melt season in 
the Chukchi Sea began slowly, and then sea-ice retreat accelerated 
rapidly in July and August. The continental shelf of the Chukchi Sea 
was sea-ice-free by mid-August; the ice edge eventually retreated 
hundreds of miles north of the shelf, and ice did not re-form over the 
continental shelf until late October (National Snow and Ice Data 
Center, 2007). Ovsyanikov et al. (2007, pp. 2-3) reported that many of 
the walruses arriving at Wrangel Island, Russia, in August 2007 were 
emaciated and weak, some too exhausted to flee or defend themselves 
from polar bears patrolling the coast. The authors attributed the poor 
condition of these animals to the rapid retreat of sea ice off of the 
shelf in July to waters too deep for walrus to feed. They also noted 
that the exhausted walruses could not find enough food near the island 
for recovery (Ovsyanikov et al. 2007, p. 3).
    Females with dependent young are likely to be disproportionally 
affected by prey depletion and increased reliance on coastal haulouts 
as a foraging base. Females with dependent young require two to three 
times the amount of food needed by nonlactating females (Fay 1982, p. 
159). Over the past decade, females and dependent calves have responded 
to the loss of sea ice in late summer by occupying coastal haulouts 
along the coast of Chukotka, Russia, and more recently (2007-2010) 
haulouts along the coast of Alaska. Females typically nurse their 
calves between short foraging forays from sea-ice platforms situated 
over productive forage areas (Ray et al. 2006, pp. 404-407). Drifting 
ice provides walrus passive transport and access to new foraging areas 
with minimal effort. In 2007, radio-tagged females traveled on average, 
30.7 km (19 mi) on foraging trips from several haulouts located along 
the Chukotka coastline (Kochnev et al. 2008, p. 265). Although we do 
not know the average distance of foraging trips taken from an ice 
platform, in general, we would expect them to be relatively short, 
because when the ice is over productive prey areas, the female only has 
to dive to the bottom and back up to the ice (Ray et al. 2006, pp. 406-
407). Because calves do not have the swimming endurance of adults, if 
sufficient prey is not located within the swimming distance of the 
calf, the female either may not be able to obtain adequate nutrition or 
the calf may be abandoned when the female travels to locations beyond 
the swimming capability of the calf (Cooper et al. 2006, pp. 98-102). 
Lack of adequate prey for females could eventually lead to reduced body 
condition, lower reproductive success, and potentially death. Abandoned 
calves could face increased mortality from drowning, starvation, or 
predation.
    In summary, by the end of the 21st century, ice-free conditions are 
expected to persist across the continental shelf of the Chukchi Sea for 
a period of up to several months (Douglas 2010). Based

[[Page 7647]]

on the observed responses of walruses to periods of low ice cover in 
the Chukchi Sea in recent years, we expect walruses to become 
increasingly dependent on coastal haulouts as a foraging base, with 
animals restricted to coastal haulouts for most of the summer and into 
the fall and early winter. Walruses have the ability to use land in 
addition to ice as a resting site and foraging base, which will provide 
them alternate, if not optimal (as explained above), resting habitat. 
However, given the concentration of large numbers of animals in 
relatively small areas, the large amount of prey needed to sustain each 
walrus, and the increasing length of time coastal haulouts will have to 
be used due to sea-ice loss, the increased dependence on coastal 
haulouts is expected to result in increased competition for food 
resources in areas accessible from the coastal haulouts. Because of the 
energetic demands of lactation and limited mobility of calves, female 
walruses with dependent young are likely to be disproportionally 
affected by changes in habitat use patterns. Because near-shore food 
resources are unlikely to be able to support the current population, 
walruses will be required to swim farther to obtain prey, which will 
increase energetic costs. Accordingly, near-shore prey depletion will 
likely result in a population decline over time. It is unlikely that 
the projected increase in ice-free months in the Bering Sea will alter 
the behavior or survival rates of males at terrestrial haulouts because 
these males do not rely on sea ice as a foraging platform. In addition, 
males have an advantage over females in that they are bigger and 
stronger and have no responsibilities related to the care of calves, 
and thus, can travel as far as necessary to forage.
    The degree to which depletion of food resources near coastal 
haulouts will limit population size will depend on a variety of 
factors, including: The location of coastal walrus haulouts, the number 
of animals utilizing the haulouts, the duration of time walruses occupy 
the haulouts, and the robustness of the prey base within range of those 
haulouts. However, it is highly unlikely that the current population 
can be sustained from coastal haulouts alone. In particular, females 
and their calves will be susceptible to the increased energetic demands 
of foraging from coastal haulouts. We do not anticipate effects to 
males using coastal haulouts in the Bering Sea, because their current 
behavior can continue unaltered into the future. We do not have 
evidence that prey depletion is currently having a population-level 
effect on the Pacific walrus. Our concern is based on projections of 
continued and more extensive sea-ice loss that will force the animals 
onto land. Therefore, we conclude that loss of sea-ice habitat, leading 
to dependence on coastal haulouts and localized prey depletion, will 
contribute to other negative impacts associated with sea-ice loss, and 
is a threat to the Pacific walrus in the foreseeable future.
Increased Vulnerability to Disturbances and Trampling
    Another consequence of greater reliance on coastal haulouts is 
increased levels of disturbances and increased rates of mortalities and 
injuries associated with trampling. Walruses often flee land or ice 
haulouts in response to disturbances. Disturbance can come from a 
variety of sources, either anthropogenic (e.g., hunters, airplanes, 
ships) or natural (e.g., predators) (Fay et al. 1984, pp. 114-118, 
Kochnev 2004, p. 286). Haulout abandonment represents an increase in 
energy expenditure and stress, and disturbance events at densely packed 
coastal haulouts can result in intra-specific trauma and mortalities 
(COSEWIC 2006, pp. 25-26). Although disturbance-related mortalities at 
all-male haulouts in the Bering Sea are relatively uncommon (Fay and 
Kelly 1980, p. 244; Kochnev 2004, p. 285), the situation at mixed 
haulouts is different; because of their smaller size, calves, 
juveniles, and females are more susceptible to trampling injuries and 
mortalities (Fay and Kelly 1980, pp. 226, 244). Females likely avoid 
using terrestrial haulouts because their offspring are vulnerable to 
predation and trampling (Nikiforov et al. 2007, pp. 1-2; Ovsyanikov et 
al. 2007, pp. 1-3; Kochnev 2008, pp. 17-20; Kochnev et al. 2008, p. 
265).
    When walruses are disturbed on ice floes, escape into the water is 
relatively easy because fewer animals are concentrated in one area. In 
comparison, aggregations of walruses on land are often very large in 
number, densely packed, and ``layered'' several animals deep (Nikiforov 
et al. 2007, p. 2). The presence of some large males in groups using 
Chukchi Sea coastal haulouts increases the danger to calves, juveniles, 
and females. Consequently, the probability of direct mortality or 
injury due to trampling during stampedes is greater at terrestrial 
haulouts than it is on pack ice (USFWS 1994, p. 12). Also, whether on 
ice or land, calves may be abandoned as a result of disturbance to a 
haulout (Fay et al. 1984, p. 118).
    In addition, sources of disturbance are expected to be greater at 
terrestrial haulouts than in offshore pack ice habitats, because the 
level of human activity such as hunting, fishing, boating, and air 
traffic is far greater along the coast. Haulout abandonment has been 
documented from these sources (Fay et al. 1984; p. 114; Kochnev 2004, 
pp. 285-286). There is also a greater chance of disturbance from 
terrestrial animals (Kochnev 2004, p. 286). As sea ice declines, and 
both polar bears and walruses are increasingly forced onto land 
bordering the Chukchi Sea, we anticipate that there will be greater 
interaction between the two species, especially during the summer. We 
expect that one outcome of increased interactions will be increased 
walrus mortality due to predation (discussed below). Of equal, or more 
importance than predation is the disturbance caused at a haulout 
through the arrival or presence of a polar bear, which can cause 
stampeding. Repeated stampeding also increases energy expenditure and 
stress levels, and may cause walruses to abandon the haulout (COSEWIC 
2006, p. 25).
    Losses that can occur when large numbers of walruses use 
terrestrial haulouts are illustrated by observations in 2007, along the 
coast of Chukotka, Russia. In response to summer sea-ice loss in 2007, 
walruses began to arrive at coastal haulouts in July, a month earlier 
than previously recorded (Kochnev 2008, pp. 17-20). Coastal 
aggregations ranged in size from 4,500 up to 40,000 animals (Ovsyanikov 
et al. 2007, pp. 1-2; Kochnev 2008, p. 17-20, Kavry et al. 2008, p. 
248-251). Hunters from the Russian coastal villages of Vankarem and 
Ryrkaipii reported more than 1,000 walrus carcasses (mostly calves of 
the year and aborted fetuses) at coastal haulouts near the communities 
in September 2007 (Nikiforov et al. 2007, p. 1; Kochnev 2008, pp. 17-
20). Noting the near absence of calves amongst the remaining animals, 
Kochnev (2008, pp. 17-20) estimated that most of the 2007 cohort using 
the site had been lost. Approximately 1,500 walrus carcasses 
(predominately adult females) were also reported near Cape Dezhnev in 
late October (Kochnev 2007, pers. comm.). Russian investigators 
estimate that between 3,000 and 10,000 animals died along the Chukotka 
coastline during the summer and fall of 2007, primarily from trampling 
associated with disturbance events at the haulouts (Kochnev 2010, pers. 
comm.).
    Relatively few large mortality events at coastal haulouts have been 
documented in the past, but they have occurred (Fay 1982, p. 226). For

[[Page 7648]]

example, Fay and Kelly (1980, p. 230) examined several hundred walrus 
carcasses at coastal haulouts on St. Lawrence Island and the Punuk 
Islands in the fall of 1978. Approximately 15 percent of those 
carcasses were aborted fetuses, 24 percent were calves, and the others 
were older animals (mostly females) ranging in age from 1 to 37 years 
old. The principal cause of death was trampling, possibly from 
disturbance-related stampedes or battling bulls. As walruses become 
increasingly dependent on coastal haulouts, interactions with humans 
and predators are expected to increase and mortality events are likely 
to become increasingly common. Long-term or chronic levels of 
disturbance related mortalities at coastal haulouts are likely to have 
a more significant population effect over time.
    We recognize that Atlantic walruses (including females and calves) 
utilize coastal haulouts to a greater extent than Pacific walruses, 
foraging from shore along a relatively narrow coastal shelf; a 
situation that is similar to what Pacific walrus may experience in the 
future during ice-free months in the Chukchi Sea. However, Atlantic 
walrus occupy an area with abundant remote islands that are free or 
nearly free from disturbance from humans or terrestrial mammals. In 
essence, their insular habitats function in a manner analogous to the 
pack ice of the Pacific walrus, providing a refugium from disturbance. 
In contrast, when Pacific walruses are restricted to terrestrial 
haulouts, they face disturbance from a variety of terrestrial predators 
and scavengers, including bears, wolverines, wolves, and feral dogs, 
and higher levels of anthropogenic disturbances, because their haulouts 
are at the edge of continental land masses and there are very few 
islands in the Bering and Chukchi Seas. Sea ice, which has typically 
acted as a refugium from disturbance for Pacific walruses, particularly 
for females and young in the Chukchi Sea, will be lost entirely, or 
almost entirely, for increasingly long time periods annually in the 
foreseeable future. Therefore, although use of coastal haulouts is a 
form of adaptability available to Pacific walruses, it comes with 
negative impacts that are not associated with coastal haulouts for 
Atlantic walruses.
    In summary, we anticipate that Pacific walruses will become 
increasingly dependent on coastal haulouts as sea ice retreats earlier 
off the continental shelf and the Bering and Chukchi Seas become ice-
free for increasingly longer periods of time. The protection normally 
provided to females and calves by the dispersal of smaller groups of 
animals across a wide expanse of sea ice will be lost during periods of 
ice-free or nearly ice-free conditions. Significant mortality events 
from trampling have been documented at large haulouts, and we 
anticipate that they will continue with much greater frequency into the 
foreseeable future, resulting in increased mortality, particularly of 
calves and females. Therefore, we conclude that disturbances and 
trampling at haulouts is a threat to the Pacific walrus now and in the 
foreseeable future.
Increased Vulnerability to Predation and Hunting
    As Pacific walruses become more dependent on coastal haulouts, they 
will become more susceptible to predation and hunting (Kochnev 2004, p. 
286). Although hunting and predation are discussed separately below 
(see Factors B and C, respectively), we also consider them here due to 
their relationship to increased loss of sea-ice habitat.
    Because of their large size and tusks, adult walruses are much less 
susceptible to predation than are young animals or females. Females 
likely avoid using terrestrial haulouts because their offspring are 
vulnerable to predation (Kochnev 2004, p. 286; Ovsyanikov et al. 2007, 
pp. 1-4; Kelly 2009, p. 302). Apparently, some polar bear routinely 
rush herds to cause a stampede, expecting that some calves will be left 
behind (Nikulin 1941; Popove 1958, 1960; as cited in Fay et al. 1984, 
p. 119). As sea ice declines in the foreseeable future, increased use 
of terrestrial habitats by both polar bears and walruses will likely 
lead to increased interaction between them, and most likely an increase 
in mortality, particularly of calves. We conclude that loss of sea ice, 
which will force increased overlap between these two species, will 
increase mortality from polar bears through direct take or indirect 
take due to trampling during stampedes. See the section on predation in 
Factor C below, for further information.
    Large concentrations of walruses on shore for longer periods of 
time could result in increased harvest levels if the terrestrial 
haulouts form near coastal villages and environmental conditions allow 
access to haulouts. Kochnev (2004, pp. 285-286) notes that many of the 
haulouts along the Chukotka coast are situated near coastal villages, 
and hunting activities at the haulouts can result in stampedes and 
cause movements from one haulout to another. Some communities in 
Chukotka situated in close proximity to the new haulouts have responded 
by developing hunting restrictions to limit disturbances to resting 
animals (Patrol 2008, p. 1; Kavry 2010, pers. comm.; Kochnev 2010 pers. 
comm.). See the section on Subsistence Hunting in Factor B below, for 
further information.
Summary of the Effects of Sea-Ice Loss on Pacific Walruses
    The Pacific walrus is an ice-dependent species. Changes in the 
extent, volume, and timing of the sea-ice melt and onset of freezing in 
the Bering and Chukchi Seas have been documented and described earlier 
in this finding, there are reliable projections that more extensive 
changes will occur in the foreseeable future. We expect these changes 
in sea ice will cause significant changes in the distribution and 
habitat-use patterns of Pacific walruses. At this time we anticipate 
that breeding behavior in winter and calving in the early spring will 
not be impacted by expected changes to sea-ice conditions, although the 
locations where these events occur will most likely change as the 
location of available sea ice shifts to the north.
    With the loss of summer sea ice, the most obvious change, which has 
already been observed, will be a greater dependence on terrestrial 
haulouts by both sexes and all age groups. Although walruses of both 
sexes are capable of using terrestrial haulouts, historically, adult 
males have used terrestrial haulouts, particularly in the Bering Sea, 
to a much greater extent than females, calves, and juveniles. The loss 
of summer sea ice means that walruses of both sexes, but females and 
their young in particular, will be using coastal haulouts for longer 
periods of time. This change is particularly notable in the Chukchi 
Sea, which has historically had sufficient sea ice in the summer so 
that females and calves could remain over the shallow continental shelf 
throughout the summer. Since approximately 2005, the Chukchi Sea has 
become ice-free or nearly so during part of the summer. This condition 
is projected to increase over time, and may occur faster than forecast. 
The consequences of this shift from sea ice to increasing use of land 
include: Risk of localized prey depletion; increased energetic costs to 
reach prey, resulting in decreased body condition; calf abandonment; 
increased mortality from stampedes, especially to females, juveniles, 
and calves; and potentially increased exposure to predation and 
hunting. These events are expected to reduce survivorship.
    As large numbers of animals are concentrated at coastal haulouts, 
prey

[[Page 7649]]

may be locally depleted, and greater distances will be required to 
obtain it. Although males at haulouts in the Bering Sea function for 
several months each year from terrestrial haulouts, females with calves 
do not typically use terrestrial haulouts, and we expect the loss of 
sea ice to have a greater impact on them through the higher energetic 
cost of obtaining food. It is likely that these factors will lead to a 
population decline over time, as fewer walruses can be supported by the 
resources available from terrestrial haulouts. In the foreseeable 
future, as the duration of ice-free periods over offshore continental 
shelf regions of the Chukchi Sea increases from 1 to up to 5 months 
(July through November), we expect the effects of prey depletion near 
terrestrial haulouts will be heightened.
    Periodic ice-free conditions, as are currently occurring, are 
expected to lead to higher mortality rates, primarily through trampling 
at haulouts when walruses congregate in large numbers. Although of 
concern, if these events happen sporadically, as has been the case in 
the past, the population may be able to recover between harsh years. 
Although trampling mortalities have been documented in the past, 
increasing use of terrestrial haulouts, the higher probability of 
disturbance occurring at these haulouts, and in the near-term, the very 
large numbers of animals using particular haulouts, increases the 
probability that mortality from trampling will become a more regular 
event.
    The increasing reliance of both polar bears and walruses on 
terrestrial environments during ice free periods will likely result in 
increased interactions between these two species. Polar bear predation 
and associated disturbances at densely crowded coastal haulouts will 
likely contribute to increased mortality levels, particularly of 
calves, and may displace animals from preferred feeding areas. Hunting 
activity at coastal haulouts does not appear to be a significant source 
of mortality at the present time, but may become more of a factor in 
the future. Local hunting restrictions at coastal haulouts have been 
established in some communities in Chukotka to reduce disturbance-
related mortalities. The efficacy of efforts to mitigate sources of 
anthropogenic disturbances at coastal walrus haulouts (including 
hunting, boating and air traffic) will influence the degree to which 
these factors will affect the Pacific walrus population. See Factors B 
and C for further discussion on harvest and predation.
    In conclusion, the loss of sea-ice habitat creates several 
stressors on the Pacific walrus population. These stressors include: 
localized prey depletion; increased energetic costs to reach prey, 
resulting in decreased body condition; calf abandonment; increased 
mortality from stampedes, especially to females, juveniles, and calves; 
and increased exposure to predation and hunting. Because the Pacific 
walrus range is large, and the animals are not all in the same place at 
the same time, not all stressors are likely to affect the entire 
population in a given year. However, all stressors represent potential 
sources of increased mortality over the current condition, in which 
these stressors occur infrequently. In the foreseeable future, as the 
frequency of sea-ice loss in the summer and fall over the continental 
shelves increases to a near-annual event and the length of time ice is 
absent over the continental shelf increases from 1 to up to 5 months, 
we expect the effects on walruses to be heightened and a greater 
percentage of the population to be affected. Increased direct and 
indirect mortality, particularly of calves, juveniles, and females, 
will result in a declining population over time. Consequently, we 
conclude that the destruction, modification, and curtailment of sea-ice 
habitat is a threat to the Pacific walrus.
Outcome of Bayesian Network Analyses
    Both the Service and USGS Bayesian network analyses (Garlich-Miller 
et al. 2011; Jay et al. 2010b) considered changes in sea ice projected 
through the 21st century. In both cases, the results indicate that 
expected loss of sea ice is an important risk factor for Pacific walrus 
population status over time. The USGS analysis deals more directly with 
projected outcomes of the Pacific walrus population, including the 
influence of sea-ice loss under different potential conditions (Jay et 
al. 2010b, p. 40). For the normative sea ice run (see Jay et al. 2010b 
for details), the probability of Pacific walruses becoming vulnerable, 
rare, or extirpated increases over time, from approximately 22 percent 
in 2050, to about 35 percent by 2075, and 40 percent in 2095 (Jay et 
al. 2010b, p. 40). A ``worst case'' influence run was also evaluated. 
For the worst case, model outputs were selected that have both the 
greatest number of ice-free months and the least ice extent for the 
Bering and Chukchi Seas and, therefore, represent the worst possible 
situation. The outcome for the worst case influence run for sea ice 
indicated that the probability of Pacific walruses becoming vulnerable, 
rare, or extirpated approximately doubles at mid-century to 40 percent, 
and reaches approximately 45 percent at 2075 (Jay et al. 2010b, p. 40). 
At the end of 21st century, the probability of Pacific walruses 
becoming vulnerable, rare, or extirpated in both the worst case 
scenario and the normative run are essentially equal, at about 40 
percent; an outcome that is due to the projected amount of sea-ice loss 
being basically the same under the worst case and normative case by the 
end of the century. We note, however, that the models and emissions 
scenarios used by the IPCC in 2007 were the basis for this analysis. 
Thus, it is possible that the ``worst case scenario'' reflects the 
``faster than forecast'' loss of sea ice that may be realized if sea-
ice loss continues on the current downward trend that began in 1979 
(National Snow and Ice Data Center, 2010). Regardless of which 
trajectory will actually occur, the modeling efforts show that the 
future status of the Pacific walrus is linked to sea ice, which already 
is declining substantially, and more rapidly than previously projected.
Effects of Global Climate Change on Pacific Walrus Prey Species
    The shallow, ice-covered waters of the Bering and Chukchi Seas 
provide habitat that supports some of the highest benthic biomass in 
the world (Grebmeier et al. 2006a, p. 1461; Ray et al. 2006, p. 404). 
Sea-ice algae, pelagic (open ocean) primary productivity, and the 
benthos (organisms that live on or in the sea floor) are tightly linked 
through the sedimentation of organic particles (Grebmeier et al. 2006b, 
p. 339). Sea-ice algae provide a highly concentrated and high-quality 
food source for plankton food webs in the spring, which translates to 
high-quality food for the benthos such as clams (Grebmeier et al. 
2006b, p. 339; McMahon et al. 2006, pp. 2-11; Gradinger 2009, p. 1211). 
Because zooplankton, which also feed on the algae, have correspondingly 
low populations at this time in the spring, much of the primary 
productivity of algae falls to the sea floor, where it is available to 
the benthic invertebrates (Grebmeier et al. 2006b, p. 339).
    Spatial distribution and abundance in biomass in benthic habitat 
across the Bering and Chukchi Seas is influenced by a variety of 
ecological, oceanographic, and geomorphic features. In the subarctic 
region of the Bering Sea (from the Bering Strait south to latitude 50 
degrees), benthic organisms are preyed upon by demersal fish (living 
near the bottom of the water column) and epifaunal invertebrates (those 
organisms living on top of the sea floor rather than in it), whose 
distribution is limited to the north by cold water (less than 0 [deg]C 
(32 [deg]F))

[[Page 7650]]

resulting from seasonal sea-ice cover, forming a temperature-mediated 
ecological boundary. In the absence of demersal fish and predatory 
invertebrates, benthic-feeding whales, walrus, and sea-birds are the 
primary consumers in the Arctic region of the Bering Sea (Grebmeier et 
al. 2006b, pp. 1461-1463).
    Within the Arctic region of the Bering Sea, marginal sea-ice zones 
and areas of polynyas appear to be ``hot spots'' of high benthic 
diversity and productivity (Grebmeier and Cooper 1995, p. 4439). 
Benthic biomass is particularly high in the northern Bering Sea, the 
southern Chukchi Sea, and the Gulf of Anadyr. However, the high 
diversity and productivity of the benthic communities is not seen in 
the Southern Beaufort Sea shelf and areas of the eastern Chukchi Sea, 
which are influenced by the nutrient-poor Alaska coastal current (Fay 
et al. 1977, p. 12; Grebmeier et al. 1989, p. 261; Feder et al. 1994, 
p. 176; Smith et al. 1995, p. 243; Grebmeier et al. 2006b, p. 346; 
Bluhm and Gradinger 2008, p. 2).
Ocean Warming
    For the last several decades, surface air temperatures throughout 
the Arctic, over both land and water, have warmed at a rate that 
exceeds the global average, and they are projected to continue on that 
path (Comiso and Parkinson 2004, pp. 38-39; Christensen et al. 2007, p. 
904; Lawrence et al. 2008, p. 1; Serreze et al. 2009, pp. 11-12). In 
addition, the subsurface and surface waters of the Arctic Ocean and 
surrounding seas, including the Bering and Chukchi Seas have warmed 
(Steele and Boyd 1998, p. 10419; Zhang et al. 1998, p. 1745; Overland 
and Stabeno 2004, p. 309; Stabeno et al. 2007, pp. 2607-2608; Steele et 
al. 2008, p. 1; Mueter et al. 2009, p. 96). There are several 
mechanisms working in concert to cause these increases in ocean 
temperature, including: Warmer air temperatures (Comiso and Parkinson 
2004, pp. 38-39; Overland and Stabeno 2004, p. 310), an increase in the 
heat carried by currents entering the Arctic from both the Atlantic 
(Drinkwater et al., p. 25; Zhang et al. 1998, p. 1745) and Pacific 
Oceans (Stabeno et al. 2007, p. 2599; Woodgate et al. 2010, p. 1-5), 
and a shorter ice season, which decreases the albedo (reflective 
property) of ice and snow (Comiso and Parkinson 2004, p. 43; Moline et 
al. 2008, p. 271; Markus et al. 2009, p. 13). Due to their biological 
characteristics which include tolerance of considerable variations in 
temperature, direct effects to walrus are not anticipated with warmer 
ocean temperatures. Nevertheless, changes in the thermal dynamics of 
ocean conditions may affect walrus indirectly through impacts to their 
prey base. Changes to density, abundance, distribution, food quality, 
and species of benthic invertebrates may occur primarily through 
changes in habitat related to sea ice.
    Walruses are the top predator of a relatively simple food web in 
which the primary constituents are bacteria, sea-ice algae, 
phytoplankton (tiny floating plants), and benthic invertebrates (Horner 
1976, p. 179; Lowry and Frost 1981, p. 820; Grebmeier and Dunton 2000, 
p. 65; Dunton et al. 2006, p. 370; Aydin and Mueter 2007, p. 2507). Sea 
ice is important to the Arctic food webs because: (1) It is a substrate 
for ice algae (Horner 1976, pp. 168-171; Kern and Carey Jr. 1983, p. 
161; Grainger et al. 1985, pp. 25-27; Melnikov 2000, pp. 79-81; 
Gradinger 2009, p. 1201); (2) it influences nutrient supply and 
phytoplankton bloom dynamics (Lovvorn et al. 2005, p. 136); and (3) it 
determines the extent of the cold-water pool on the southern Bering 
shelf (Aydin and Mueter 2007, p. 2503; Coyle et al. 2007, p. 2900; 
Stabeno et al. 2007, p. 2615; Mueter and Litzow 2008, p. 309).
    In the spring, ice algae form up to a 1-cm- (0.4-in-) thick layer 
on the underside of the ice, but are also found at the ice surface and 
throughout the ice matrix (Horner 1976, pp. 168-171; Cota and Horne 
1989, p. 111; Gradinger et al. 2005, p. 176; Gradinger 2009, p. 1207). 
Ice algae can be released into the water through water turbulence below 
the ice, through brine drainage through the ice, or when the algal mats 
are sloughed as the ice melts (Cota and Horne 1989, p. 117; Renaud et 
al. 2007, p. 7). As noted above, sea-ice algae provide a highly 
concentrated food source for the benthos and the plankton (organisms 
that float or drift in the water) food web that is initiated once the 
ice melts (Grebmeier et al. 2006b, p.339; McMahon et al. 2006, pp. 1-2; 
Renaud et al. 2007, pp. 8-9; Gradinger 2009, p. 1211). Areas of high 
primary productivity support areas of high invertebrate mass, which is 
food for walruses (Grebmeier and McRoy 1989, p. 87; Grebmeier et al. 
2006b, p. 332; Bluhm and Gradinger 2008, p. S87).
    Spring ice melt plays an important role in the timing, amount, and 
fate of primary production over the Bering Sea shelf, with late melting 
(as occurs now) leading to greater delivery of food from primary 
production to the benthos and earlier melting (as is projected to occur 
in the future) contributing food primarily to the pelagic system (Aydin 
and Mueter 2007, p. 2505; Coyle et al. 2007, p. 2901). When ice is 
present from late March to May (as occurs now), cold surface 
temperatures, thinning ice, and low-salinity melt water suppress wind 
mixing, and cause the water column to stratify, creating conditions 
that promote a phytoplankton bloom. The burst of phytoplankton, seeded 
in part by ice algae, persists until ocean nutrients are drawn down. 
Because it is early in the season and water temperatures are cold, 
zooplankton populations are still low. Consequently, the pulse of 
phytoplankton production is not consumed by zooplankton, but instead 
sinks to the sea floor, where it provides abundant food for the benthos 
(Coyle and Cooney 1988, p. 177; Coyle and Pinchuk 2002, p. 177; Hunt 
and Stabeno 2002, p. 11; Lovvorn et al. 2005, p. 136; Renaud et al. 
2007, p. 9). Blooms form a 20- to 50-km- (12-31 mi-) wide belt off the 
ice edge and progress north as the ice melts, creating a zone of high 
productivity. In colder years in the Bering Sea, when the ice extends 
to the shelf edge, there is greater nutrient resupply through shelf-
edge eddies and tidal mixing, creating a longer spring bloom (Tynan and 
DeMaster 1997, pp. 314-315).
    The blooms that occur near the ice edge make up approximately 50 to 
65 percent of the total primary production in Arctic waters (Coyle and 
Pinchuk 2002, p. 188; Bluhm and Gradinger 2008, p. S84). High benthic 
abundance and biomass correspond to areas with high deposition of 
phytodetritus (dead algae) (Grebmeier et al. 1989, pp. 253-254; 
Grebmeier and McRoy 1989, p. 79; Tynan and DeMaster 1997, p. 315). 
Regions with the highest masses of benthic invertebrates occur in the 
northern Bering Sea southwest of St. Lawrence Island, Alaska; in the 
central Gulf of Anadyr, Russia, north and south of the Bering Strait; 
at a few offshore sites in the East Siberian Sea; and in the northeast 
sector of the Chukchi Sea (Grebmeier and Dunton 2000, p. 61; Dunton et 
al. 2005, pp. 3468, 3472; Carmack et al. 2006, p. 165; Grebmeier et al. 
2006b, pp. 346-351; Aydin and Mueter 2007, pp. 2505-2506; Bluhm and 
Gradinger 2008, p. S86). As noted above, the biomass of benthic 
invertebrates is much less in the eastern Chukchi Sea, which is under 
the influence of the nutrient-poor Alaska Coastal Current (Dunton et 
al. 2006, p. 369).
    When the ice melts early (before mid-March, as projected for the 
future), conditions that promote the phytoplankton bloom do not occur 
until late May or June (Stabeno et al. 2007, p. 2612). The difference 
in timing is important, because when the bloom

[[Page 7651]]

occurs later in the spring the surface water temperatures are 2.2 
[deg]C (3.6 [deg]F) to more than 5 [deg]C (9.4 [deg]F) warmer (Hunt and 
Stabeno 2002, p. 11); this, in turn, is an important influence on the 
metabolism of zooplankton. In cold temperatures, zooplankton consume 
less than 2 percent of the phytoplankton production (Coyle and Cooney 
1988, pp. 303-305; Coyle and Pinchuk 2002, p. 191). Warmer temperatures 
result in increased zooplankton growth rates, reduction in their time 
to maturity, and increased production rates (Coyle and Pinchuk 2002, p. 
177; Hunt and Stabeno 2002, pp. 12-14). Zooplankton are efficient 
predators of phytoplankton, and when they are abundant, they can remove 
nearly all the phytoplankton available (Coyle and Pinchuk 2002, p. 
191). Zooplankton are the primary food for walleye pollock (Theragra 
chalcogramma) and other planktivorous fishes (Hunt and Stabeno 2002, 
pp. 14-15). Consequently, when zooplankton populations are high, 
instead of the primary production being transmitted to the benthos, it 
becomes tied up in pelagic food webs. While this may be beneficial for 
fish-eating mammals, it reduces the amount of food delivered to the 
benthos and, thus, may reduce the amount of prey available to walrus 
(Tynan and DeMaster 1997, p.316; Carmack et al. 2006, p. 169; Grebmeier 
et al. 2006a, p. 1462). Most models project that sea-ice melt in the 
Bering Sea will occur increasingly early in the future, and will be 1 
month earlier by the end of the century (Douglas 2010, p. 12). This is 
consistent with recent trends over the past two decades, and 
particularly in the past few years. Based on our current understanding 
of food web dynamics in the Bering Sea, this shift in timing would 
favor a shift to pelagic food webs over benthic production, 
consequently reducing the amount of prey available to walrus.
    The importance of ice algae is not only in its role in seeding the 
spring phytoplankton bloom, but also in its nutritional value. As food 
supply to the benthos is highly seasonal, synchrony of reproduction 
with algal inputs insures adequate high-quality food for developing 
larvae or juveniles of benthic organisms (Renaud et al. 2007, p. 9). 
Ice algae have high concentrations of essential fatty acids, some of 
which cannot be synthesized by benthic invertebrates and, therefore, 
must be ingested in their diet (Arrigo and Thomas 2004, p. 477; Klein 
Breteler et al. 2005, pp. 125-126; McMahon et al. 2006, pp. 2, 5). 
Fatty acids in marine fauna play an integral role in physiological 
processes, including reproduction (Klein Breteler et al. 2005, p. 126). 
Because ice algae are a much better source of essential fatty acids 
than phytoplankton, a loss in sea ice could change the quality of food 
supplied to areas that currently support high levels of benthic 
biomass. These changes may affect the success of invertebrate 
reproduction and recruitment, which, in turn, may affect the quantity 
and quality of food available to walrus (Witbaard et al. 2003, p. 81; 
McMahon et al. 2006, pp. 10-12). By the end of the century, the March 
(winter maximum) extent of sea ice is projected to be approximately 
half of contemporary conditions (Douglas 2010, p. 8). We expect ice 
algae will persist where ice is present; however, because of the 
reduced ice extent, current areas of high benthic productivity may be 
reduced or shift northward.
    The eastern and western Bering Sea shelves are fueled by nutrient-
rich water supplied from the deep water of the Bering Sea (Sambrotto et 
al. 1984, pp. 1148-1149; Springer et al. 1996, p. 205). Concentrations 
of nitrate, phosphate, and silicate are among the highest recorded in 
the world's oceans and contribute to the high benthic productivity 
(Sambrotto et al. 1984, p. 1148; Grebmeier et al. 2006a, p. 1461; Aydin 
and Mueter 2007, p. 2504). High productivity on the northern Bering-
Chukchi shelf is supported by the delivery of nutrient-rich water via 
the Anadyr Current that flows along the western edge of the Bering Sea 
and through the Bering Strait (Springer et al. 1996, p. 206; Aydin and 
Mueter 2007, p. 2504). Thus, the movement of highly productive water 
onto the northern Bering Sea shelf supports persistent hot spots of 
high benthic productivity, which in turn support large populations of 
benthic-feeding birds, walrus, and gray whales (Aydin and Mueter 2007, 
p. 2506). This contrasts with the southern subarctic region of the 
Bering Sea, which is south of the current range of the Pacific walrus, 
where the benthic mass is largely consumed by upper tropic-level 
demersal fish and epifaunal invertebrates whose northern distribution 
is limited by a pool of cold, near-freezing water in the northern 
region of the Bering Sea.
    Benthic productivity on the northern Bering Sea shelf has decreased 
over the last two decades, coincident with a reduction of northward 
flow of the Anadyr current through the Bering Strait (Grebmeier et al. 
2006a, p. 1462). Because of recent warming trends, the northern Bering 
Sea shelf may be undergoing a transition from an Arctic to a more 
subarctic ecosystem with a reduction in benthic prey populations and an 
increase in fish populations (Overland and Stabeno 2004, p. 310; 
Grebmeier et al. 2006a, pp. 1462-1463). The Bering Sea is a transition 
area between Arctic and subarctic ecosystems, with the boundary between 
the two loosely concurrent with the extent of the winter sea-ice cover 
(Overland and Stabeno 2004, p. 309). In the eastern Bering Sea, 
reductions in sea ice have been responsible for shrinking a large 
subsurface pool of cold water with water temperatures less than 2 
[deg]C (3.6 [deg]F) (Stabeno et al. 2007, p. 2605; Mueter and Litzow 
2008, p. 313). The southern edge of the cold pool, which defines the 
boundary region between the Arctic and subarctic communities, has 
retreated approximately 230 km (143 mi) north since the early 1980s 
(Mueter and Litzow 2008, p. 316).
    The northward expansion of warmer water has resulted in an increase 
in pelagic species as subarctic fauna have colonized newly favorable 
habitats (Overland and Stabeno 2004, p. 309; Mueter and Litzow 2008, 
pp. 316-317). Walleye pollock, a species common in the subarctic, which 
avoid temperatures less than 2[deg] C (3.6 [deg]F), have now moved 
northward into the former Arctic zone. Arctic cod (Boreogadus saida), 
which prefer cold temperatures, have also moved north to remain in 
colder temperatures (Stabeno et al. 2007, p. 2605). Because of the 
redistribution of these species, benthic fauna will be facing a new set 
of predators (Coyle et al. 2007, pp. 2901-2902). The evidence suggests 
that warming on the Bering Sea shelf could alter patterns of energy 
flow and food web relationships in the benthic invertebrate community, 
leading to overall reductions in biomass of benthic invertebrates 
(Coyle et al. 2007, p. 2902).
    Continued changes in the extent, thickness, and timing of the melt 
of sea ice are expected to create shifts in production and species 
distributions (Overland and Stabeno 2004, p. 316). Because some 
residents of the benthos are very long lived, it may take many years of 
monitoring to observe change (Coyle et al. 2007, p. 2902). Many 
simultaneous changes (e.g., ocean currents, temperature, sea-ice 
extent, and wind patterns) are occurring in walrus-occupied habitats, 
and thus may impact walrus' prey base. Rapid warming might cause a 
major restructuring of regional ecosystems (Carmack and Wassmann 2006, 
p. 474; Mackenzie and Schiedek 2007, p. 1344). Mobile species such as 
fishes have the ability to move to areas of thermal preference and 
follow key forage species (Mueter et al. 2009, p. 106); immobile

[[Page 7652]]

species such as bivalves must cope with the conditions where they are.
    Projections by Douglas (2010, pp. 7, 23) indicate that the March 
(yearly maximum) sea-ice extent in the Bering Sea will be about 25 
percent less than the 1979-1988 average by mid-century, and 60 percent 
less by the end of the century. In addition, spring melt of sea ice 
will occur increasingly earlier, and on average will be one month 
sooner by the end of the century (Douglas 2010, p. 8). As described 
above, the earlier spring melt may lead to a change in the food web 
dynamics that favors pelagic predators, which feed on zooplankton, over 
the delivery of high quantities of quality food to benthic 
invertebrates. In addition, reductions in the extent of the winter sea-
ice cover may lead to a further or more permanent expansion of the 
subarctic ecosystem northward into the Arctic. Although there is 
uncertainty about the specific consequences of these changes, the best 
available scientific information suggests that because of the likely 
decreases in the quantity and quality of food delivered to benthic 
invertebrates, and because of a potential increase in predators from 
the south, the amount and distribution of preferred prey (bivalves) 
available to walrus in the Bering Sea will likely decrease in the 
foreseeable future as a result of the loss of sea ice and ocean 
warming. The extent to which this decrease may result in a curtailment 
of the range of the Pacific walrus or limit the walrus population in 
the future is unknown, and at this time we do not have sufficient 
information to predict it with reliability. The implications of the 
available information, however, are that impacts may include 
modification of habitat that could contribute to a reduction in the 
range of the Pacific walrus at the southern edge of its current 
distribution, as well as a possible reduction in the walrus population 
because of reduced prey. Although our conclusion is based on the best 
available science, we recognize that its validity rests on ecological 
hypotheses that are currently being tested.
Ocean Acidification
    Since the beginning of the industrial revolution in the mid-18th 
century, the release of carbon dioxide (CO2) from human 
activities (``anthropogenic CO2'') has resulted in an 
increase in atmospheric CO2 concentrations, from 
approximately 280 to approximately 390 ppm currently, with 30 percent 
of the increase occurring in the last three decades (NOAA, http://www.climatewatch.noaa.gov/2009/articlesclimate-change-atmospheric-carbon-dioxide, downloaded 20 July 2010).
    The global atmospheric concentration of CO2 is now 
higher than experienced for more than 800,000 years (L[uuml]thi et al. 
2008, p. 379; Scripps 2011, p. 4). Over the industrial era, the ocean 
has been a sink for anthropogenic carbon emissions, absorbing about 
one-third of the atmospheric CO2 (Feely et al. 2004, p. 362; 
Canadell et al. 2007, pp. 18867-18868). When CO2 is absorbed 
by seawater, chemical reactions occur that reduce seawater pH (a 
measure of acidity) and the concentration of carbonate ions, in a 
process known as ``ocean acidification.''
    Ocean acidification is a consequence of rising atmospheric 
CO2 levels (The Royal Society 2005, p.1; Doney et al. 2008, 
p. 170). Seawater carbonate chemistry is governed by a series of 
chemical reactions (CO2 dissolution, acid/base chemistry, 
and calcium carbonate dissolution) and biologically mediated reactions 
(photosynthesis, respiration, and calcium carbonate precipitation) 
(Wootton et al. 2008, p. 18848; Bates and Mathis 2009, p. 2450). The 
marine carbonate reactions allow the ocean to absorb CO2 in 
excess of potential uptake based on carbon dioxide solubility alone 
(Denman et al. 2007, p. 529). Consequently, the pH of ocean surface 
waters has already decreased (become more acid) by about 0.1 units 
since the beginning of the industrial revolution (Caldeira and Wickett, 
2003, p. 365; Orr et al. 2005, p. 681).
    The absorption of carbon dioxide by seawater changes the chemical 
equilibrium of the inorganic carbon system and reduces the 
concentration of carbonate ions. Carbonate ions are required by 
organisms like clams, snails, crabs, and corals to produce calcium 
carbonate, the primary component of their shells and skeletons. 
Decreasing concentrations of carbonate ions may place these species at 
risk (Green et al. 2004, p. 729-730; Orr et al. 2005, p. 685; Gazeau et 
al. 2006 p. 1; Fabry et al. 2008, p. 419-420; Comeau et al. 2009, p. 
1877; Ellis et al. 2009, p. 41). Two forms of calcium carbonate 
produced by marine organisms are aragonite and calcite. Aragonite, 
which is 50 percent more soluble in seawater than calcite, is of 
greatest importance in the Arctic region because clams, mussels, 
snails, crustaceans, and some zooplankton use aragonite in their shells 
and skeletons (Fritz 2001, p. 53; Fabry et al. 2008, p. 417; Steinacher 
et al. 2009, p. 515).
    When seawater is saturated with aragonite or calcite, the formation 
of shells and skeletons is favored; when undersaturated, the seawater 
becomes corrosive to these structures and it becomes physiologically 
more difficult for organisms to construct them (Orr et al. 2005, p. 
685; Gazeau et al. 2007, p. 2-5; Fabry et al. 2008, p. 415; Talmage and 
Gobler 2009, p. 2076; Findlay et al. 2010, pp. 680-681). The waters of 
the Arctic Ocean and adjacent seas are among the most vulnerable to 
ocean acidification, with undersaturation of aragonite projected to 
occur locally within a decade (Orr et al. 2005, p. 683; Chierici and 
Fransson 2009, pp. 4972-4973; Steinacher et al. 2009, p. 522). To date, 
aragonite saturation has decreased in the top 50 m (164 ft) in the 
Canadian Basin (Yamamoto-Kawai et al. 2009, p. 1099), and under-
saturated waters have been documented on the Mackenzie shelf (Chierici 
and Fransson 2009, p. 4974), Chukchi Sea (Bates and Mathis 2009, p. 
2441), and Bering Sea (Fabry et al. 2009, p. 164).
    Factors that contribute to undersaturation of seawater with 
aragonite or calcite are: upwelling of carbon dioxide-rich subsurface 
waters; increased carbon dioxide concentrations from anthropogenic 
CO2 uptake; cold water temperatures; and fresher, less 
saline water (Feely et al. 2008, p. 1491; Chierici and Fransson 2009, 
p. 4966; Yamamoto-Kawai et al. 2009, p. 1099). The loss of sea ice 
(causing greater ocean surface to be exposed to the atmosphere), the 
retreat of the ice edge past the continental shelf break that favors 
upwelling, increased river runoff, and increased sea ice and glacial 
melt are forces that favor undersaturation (Yamamoto-Kawai et al. 2009, 
pp. 1099-1100; Bates and Mathis 2009, pp. 2446, 2449-2450). The 
projected increase of 3 to 5 months of ice-free conditions in the 
Bering and Chukchi Seas by Douglas (2010, p. 7) indicates the potential 
for increased CO2 absorption in the Arctic over the next 
century beyond what would occur from predicted CO2 increases 
alone. However, there are opposing forces that may mitigate 
undersaturation to some extent, including photosynthesis by 
phytoplankton that may increase with reduced sea ice, and warmer ocean 
temperatures (Bates and Mathis 2009, p. 2451). However, according to 
Steinacher et al. (2009, p. 530), the question is not whether 
undersaturation will occur in the Arctic, but how large an area will be 
affected, how many months of the year it will occur, and how large its 
magnitude.
    Because acid-base balance is critical for all organisms, changes in 
carbon dioxide concentrations and pH can affect reproduction, larval 
development, growth, behavior, and survival of all marine organisms 
(Green et al. 1998, p.

[[Page 7653]]

23; Kurihara and Shirayama 2004, pp. 163-165; Berge et al. 2006, p. 
685; Fabry et al. 2008, pp. 420-422; Kurihara 2008, pp. 277-282; 
P[ouml]rtner 2008, pp. 209-211; Ellis et al. 2009, pp. 44-45; Talmage 
and Gobler 2009, p. 2076; Findlay et al. 2010, pp. 680-681). 
P[ouml]rtner (2008, p. 211) suggests that heavily calcified marine 
groups may be among those with the poorest capacity to regulate acid-
base status. Although some animals have been shown to be able to form a 
shell in undersaturated conditions, it comes at an energetic cost which 
may translate to reduced growth rate (Talmage and Gobler 2009, p. 2075; 
Findlay et al. 2010, p. 679; Gazeau et al. 2010, p. 2938), muscle 
wastage (P[ouml]rtner 2008, p. 210), or potentially reduced 
reproductive output. Because juvenile bivalves have high mortality 
rates, if aragonite undersaturation inhibits planktonic larval bivalves 
from constructing shells (Kurihara 2008, p. 277) or inhibits them from 
settling (Hunt and Scheibling 1997, pp. 274, 278; Green et al. 1998, p. 
26; Green et al. 2004, p. 730; Kurihara 2008, p. 278), the increased 
mortality would likely have a negative effect on bivalve populations.
    The effects of ocean acidification on walrus may be through changes 
in their prey base, or indirectly through changes in the food chain 
upon which their prey depend. Walruses forage in large part on 
calcifying invertebrates (Ray et al. 2006, pp. 407-409; Sheffield and 
Grebmeier 2009, pp. 767-768; also see discussion of diet, above). 
Aragonite undersaturation has been documented in the area occupied by 
Pacific walrus (Bates and Mathis 2009, p. 2441; Fabry et al. 2009, p. 
164), and it is projected to become widespread in the future 
(Steinacher 2009, p. 530; Fr[ouml]licher and Joos 2010, pp. 13-14). 
Thus, it is possible that mollusks and other calcifying organisms may 
be negatively affected through a variety of mechanisms, described 
above. While the effects of observed ocean acidification on the marine 
organisms are not yet documented, the progressive acidification of 
oceans is expected to have negative impacts on marine shell-forming 
organisms in the future (The Royal Society 2005, p. 21; Denman et al. 
2007, p. 533; Doney et al. 2009, p. 176; Kroeker et al. 2010, p. 9).
    Uncertainty regarding the general effects of ocean acidification 
has been summarized by the Royal Society (2005, p. 23): ``Organisms 
will continue to live in the oceans wherever nutrients and light are 
available, even under conditions arising from ocean acidification. 
However, from the data available, it is not known if organisms at the 
various levels in the food web will be able to adapt or if one species 
will replace another. It is also not possible to predict what impacts 
this will have on the community structure and ultimately if it will 
affect the services that the ecosystems provide.'' Consequently, 
although we recognize that effects to calcifying organisms, which are 
important prey items for Pacific walrus, will likely occur in the 
foreseeable future from ocean acidification, we do not know which 
species may be able to adapt and thrive, or the ability of the walrus 
to depend on alternative prey items. As noted in the introduction, the 
prey base of walrus includes over 100 taxa of benthic invertebrates 
from all major phyla (Sheffield and Grebmeier 2009, pp. 761-777). 
Although walruses are highly adapted for obtaining bivalves, they also 
have the potential to switch to other prey items if bivalves and other 
calcifying invertebrate populations decline. Whether other prey items 
would fulfill walrus nutritional needs over their life span is unknown 
(Sheffield and Grebmeier 2009, p. 770), and there also is uncertainty 
about the extent to which other suitable non-bivalve prey might be 
available, due to uncertainty about the effects of ocean acidification 
and the effects of ocean warming.
    Both Bayesian network models (Garlich-Miller et al. 2010; Jay et 
al. 2010b) indicate that ocean warming and ocean acidification are 
likely to have little effect on Pacific walrus future status, but these 
conclusions were primarily because of the high degree of uncertainty 
associated with these factors. As described above, our analysis 
indicates that earlier melting of ice in the spring, a decreased extent 
of ice in winter and spring, and warming of the ocean may lead to 
changes in the distribution, quality, and quantity of food available to 
Pacific walrus over time. In addition, in the future, ocean 
acidification has the potential to have a negative impact on calcifying 
organisms, which currently represent a large portion of the walrus' 
diet. The best available science does not indicate that either of these 
factors will have a positive impact on the availability, quality, or 
quantity of food available to the walrus in the future. However, we are 
also unable to predict to what extent these factors may limit the 
Pacific walrus population in the future, in terms of reduction in its 
range or abundance, or the extent to which the walrus may be able to 
adapt to a changing prey base. Therefore, we conclude that ocean 
warming and ocean acidification are not threats to the Pacific walrus 
now or in the foreseeable future, although we acknowledge that the 
general indications are that impacts appear more likely to be negative 
than positive or neutral.
Summary of Factor A
    We have analyzed the effects of the loss of sea ice, ocean warming, 
and ocean acidification as related to the present or threatened 
destruction, modification, or curtailment of the habitat or range of 
the Pacific walrus. Although we are concerned about the changes to 
walrus prey that may occur from ocean acidification and warming, and 
theoretically we understand how those stressors might operate, ocean 
dynamics are very complex and the changing conditions and related 
outcomes for these stressors are too uncertain at this time for us to 
conclude that these stressors are a threat to Pacific walrus now or in 
the foreseeable future.
    Because of the loss of sea ice, Pacific walruses will be forced to 
rely on terrestrial haulouts to a greater and greater extent over time. 
Although coastal haulouts have been traditionally used by males, in the 
future both sexes and all ages will be restricted to coastal habitats 
for a much greater period of time. This will expose all individuals, 
but especially calves and females to increased stress, energy 
expenditure, and death or injury from disturbance-caused stampedes from 
terrestrial haulouts. Calf abandonment, and increased energy 
expenditure for females and calves is likely to occur from prey 
depletion near terrestrial haulouts. Increased energy expenditure could 
lead to decreased condition and decreased survival. In addition, there 
may be a small increase in direct mortality or injury of calves and 
females due to increased predation or hunting as a result of greater 
use of terrestrial haulouts. Although some of these stressors are 
acting on the population currently, we anticipate that their magnitude 
will increase over time as sea-ice loss over the continental shelf 
occurs more frequently and more extensively. Due to the projected 
increases in sea-ice habitat loss and the resultant stressors 
associated with increased dependence on coastal haulouts, as described 
above, we do not anticipate the projected Pacific walrus population 
decline to stabilize in the foreseeable future. Rather, the best 
scientific information available leads to a conclusion that the Pacific 
walrus will be increasingly at risk. Through our analysis, we have 
concluded that loss of sea ice, with its concomitant changes to walrus 
distribution and life-history

[[Page 7654]]

patterns, will lead to a population decline. Therefore, we conclude, 
based on the best scientific and commercial data available, that the 
present or threatened destruction, modification, or curtailment of its 
habitat or range is a threat to Pacific walrus.

Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    The following potential factors that may result in overutilization 
of Pacific walrus are considered in this section: (1) Recreation, 
scientific, or educational purposes; (2) U.S. import/export; (3) 
commercial harvest; and (4) subsistence harvest. Under Factor A, we 
also discuss the potential increase in subsistence hunting associated 
with increasing dependence of Pacific walrus on coastal haulouts caused 
by the loss of sea-ice habitat.
Recreation, Scientific, or Educational Purposes
    Overutilization for recreational, scientific, or educational 
purposes is currently not considered a threat to the Pacific walrus 
population. Recreational (sport) hunting has been prohibited in the 
United States since 1979. Russian legislation also prohibits sport 
hunting of Pacific walruses. The Marine Mammal Protection Act of 1972, 
as amended (16 U.S.C. 1361, et seq.) (MMPA), allows the Service to 
issue a permit authorizing the take of walrus for scientific purposes 
in the United States, provided that the research will further a bona 
fide and necessary or desirable scientific purpose. The Service must 
consider the benefits to be derived from the research and the effects 
of the taking on the stock, and must consult with the public, experts 
in the field, and the United States Marine Mammal Commission.
    Similarly, any take for an educational purpose is allowed by the 
MMPA only after rigorous review and with appropriate justification. No 
permits authorizing the take of walrus for educational and public 
display purposes have been requested in the United States since the 
1990s. The Service has worked with the public display community to 
place stranded animals, which the Service has determined cannot be 
returned to the wild, at facilities for educational and public display 
purposes. By placing stranded walruses, which would otherwise be 
euthanized, at facilities that are able to care for and display the 
animals, we believe needs for the domestic public display community in 
the United States have been, and will continue to be, met. The Russian 
Federation intermittently authorizes the taking of walrus from the wild 
for scientific and educational purposes. For example, in 2009, a 
collection permit was issued for take of up to 40 walrus calves from 
the wild to be used for public display. This take was included in the 
subsistence harvest quota, and is therefore considered sustainable. We 
have no information that would lead us to believe this level of take 
from the wild will increase in the foreseeable future.
    Based on the above, we conclude that utilization of walrus for 
recreational, scientific, or educational purposes is not a threat to 
the Pacific walrus population. Protections and regulatory mechanisms in 
both the United States and the Russian Federation have stopped 
recreational hunting. In the United States, the MMPA has effectively 
ensured that any removal for scientific or educational purposes has a 
bona fide and necessary or desirable scientific basis. In the Russian 
Federation, take for scientific or educational purposes is controlled 
by a quota. We believe the United States and the Russian Federation 
will continue to ensure that any future removal of walrus for 
recreational, scientific, or educational purposes will be consistent 
with the long-term conservation of the species. Therefore, we have 
determined, based on the best scientific and commercial data available, 
that the utilization of Pacific walrus for recreational, scientific, or 
educational purposes is not a threat to the species now or in the 
foreseeable future.
United States Import/Export
    Based on data from the Service's Law Enforcement Management 
Information System (LEMIS), in 2008 more than 16,000 walrus parts, 
products, and derivatives (ivory jewelry, carvings, bone carvings, 
ivory pieces, and tusks) were imported into or exported from the United 
States. Over 98 percent of those specimens were from walrus that had 
originated in the United States. Most of these specimens were 
identified as fossilized bone and ivory shards, principally dug from 
historic middens on St. Lawrence Island, or carvings from such. 
Therefore, the harvest of the source animals predates adoption of the 
MMPA in 1972, and does not represent a threat to the species.
    Since the passage of the MMPA in 1972, ivory and bone can only be 
exported from the United States after it has been legally harvested, 
and substantially altered to qualify as an Alaska Native handicraft and 
as a personal effect or as part of a cultural exchange. Trade in raw 
post-MMPA walrus ivory is closely monitored by the Service through 
existing import/export regulations (Garlich-Miller et al. 2011, Section 
3.5.1 ``International Agreements'').
    Most of the walrus parts imported into or exported from the United 
States are derived from historic ivory and bone shards, and parts from 
newly harvested walrus are subject to the MMPA requirements that limit 
U.S. trade to Alaska Native handicrafts. Therefore, we have determined, 
based on the best scientific and commercial data available, that United 
States Import/Export is not considered to be a threat to the Pacific 
walrus now or in the foreseeable future.
Commercial Harvest
    Commercial harvest of the Pacific walrus is prohibited in the U.S., 
and has not occurred in Russia since 1991 (see discussion below). 
Pacific walrus ivory and meat was available on the commercial market 
starting in the seventeenth century (Fay 1957, p. 435; Elliot 1982, p. 
98). Since then, commercial harvest levels have varied in response to 
population size and economic demand. Several of the larger reductions 
in the Pacific walrus population have been attributed to unsustainable 
harvest levels, largely driven by commercial hunting (Fay 1957, p. 437; 
Bockstoce and Botkin 1982, p. 183). Harvest regulations enacted in the 
United States and Russia in the 1950s and 1960s that reduced the size 
of the harvest and provided protection to females and calves allowed 
the population to recover and peak in the 1980s (Fay et al. 1989, p. 
1).
    Commercial harvest of marine mammals in U.S. waters is currently 
prohibited by the MMPA. Commercial harvest was last conducted in Russia 
in 1991 (Garlich-Miller and Pungowiyi 1999, p. 59). Russian legislation 
still allows for a commercial harvest, although a decree from the 
Russian Fisheries Ministry allocating a commercial harvest quota would 
be required prior to resumption of harvest (Kochnev 2010, pers. comm.). 
Quota recommendations are determined by sustainable removal levels, 
which are based on the total population and productivity estimates 
(Garlich-Miller and Pungowiyi 1999 p. 32). Therefore, any potential 
future commercial harvest in Russia is unlikely to become a threat to 
the population.
    Commercial hunting of Pacific walrus is banned in the United 
States. Regulatory protections in the Russian Federation have been 
effective in ensuring that any removal for commercial purposes is 
consistent with

[[Page 7655]]

long-term conservation of the species. Therefore, we have determined, 
based on the best scientific and commercial data available, that 
commercial harvest is not a threat to Pacific walrus either now or in 
the foreseeable future.
Subsistence
    Pacific walrus have been an important subsistence resource for 
coastal Alaskan and Russian Natives for thousands of years (Ray 1975, 
p. 10). In 1960, the State of Alaska restricted the subsistence harvest 
of female walrus to seven per hunter per year in an effort to recover 
the population from a reduced state. Concurrently, Russia also 
implemented harvest quotas and prohibited shooting animals in the water 
(to reduce lost animals) (Fay et al. 1989, p. 4). In 1961, the State of 
Alaska further reduced the quota to five females per hunter per year, 
still allowing an unlimited number of males to be hunted. The limit of 
five adult females per hunter remained in effect until 1972, when 
passage of the Marine Mammal Protection Act transferred management 
responsibility to Federal control (Fay et al. 1997, p. 548). As a 
result of reducing the numbers of females harvested, the population 
increased substantially through the 1960s and 1970s, and by 1980 was 
probably approaching the carrying capacity of the habitat (Fay et al. 
1989, p. 4).
    Total harvest removals (combined commercial and subsistence 
harvests in the United States and Russia), including estimates of 
animals struck and lost, for the 1960s and 1970s averaged 5,331 and 
5,747 walrus per year. Between the years of 1976 and 1979, the State of 
Alaska managed the walrus population under a federally imposed 
subsistence harvest quota of 3,000 walrus per year. Relinquishment of 
management authority by Alaska to the Service in 1979 lifted this 
harvest quota (the MMPA conditionally exempts Alaska Natives from the 
take prohibitions; i.e., subsistence harvest must not be conducted in a 
wasteful manner), which may have also contributed to the increased 
harvest rates in subsequent years (USFWS 1994, p. 2). Specifically, the 
1980s saw an increase in harvest, with a total removal estimate 
averaging 10,970 walrus per year (Service, unpublished data). The 
increased harvest rates in this decade may reflect several factors, 
including the absence of a harvest quota (USFWS 1994, p. 2), commercial 
harvest in Russia, and increased availability of walruses to 
subsistence hunters coinciding with the population reaching carrying 
capacity (Fay and Kelly 1989, p. 1; Fay et al. 1997, p. 558). The 
increase in harvest in the 1980s was accompanied by an increase in the 
proportion of females harvested, and may have caused a population 
decline (Fay et al. 1997, p. 549). Harvest levels in the 1990s were 
about half those of the previous decade, averaging 5,787 walrus per 
year. The 2000-2008 average annual removal, which was 5,285 walrus per 
year, was about 9 percent lower than the removal in the 1990s (Service, 
unpublished data). In the United States for the years 2004-2008, the 
communities of Gambell and Savoonga on St. Lawrence Island, Alaska, 
have accounted for 84 percent of the reported U.S. harvest and 43 
percent of the harvest rangewide (Garlich-Miller, et al. 2011, Section 
3.3.1.4 ``Regional Harvest Patterns''). The St. Lawrence Island average 
reported harvest, not corrected for animals that are struck and lost or 
hunter noncompliance with the Marking Tagging and Reporting Program, 
(the struck and lost correction and the MTRP are discussed below) for 
2004-2008 is 988 animals (Service, unpublished data).
    The lack of information on population status or trends makes it 
difficult to quantify sustainable removal levels for the Pacific walrus 
population (Garlich-Miller et al. 2011, Section 3.3.1.5 ``Harvests 
Sustainability''). Recent (2003-2007) annual harvest removals in the 
United States and Russia have ranged from 4,960 to 5,457 walrus per 
year, representing approximately 4 percent of the minimum population 
estimate of 129,000 animals (FWS 2010, p. 2). These levels are lower 
than those experienced in the early 1980s (8,000-10,000 per year) that 
led to a population decline (Fay et al. 1989 pp. 3-4). Chivers et al. 
(1999, p. 239) modeled walrus population dynamics and estimated the 
maximum net productivity rate (Rmax) for the Pacific walrus population 
at 8 percent per year. Wade (1998, p. 21) notes that one half of Rmax 
(4 percent for Pacific walruses) is a reasonably conservative (i.e., 
sustainable) potential biological removal (PBR) level for marine mammal 
populations below carrying capacity, because it provides a reserve for 
population growth or recovery. The PBR level, as defined under the 
MMPA, is the maximum number of animals, not including natural 
mortalities, that may be removed from a marine mammal stock while 
allowing that stock to reach or maintain its optimum sustainable 
population. Changes in productivity rates or population size could 
eventually result in unsustainable harvest levels if harvest rates do 
not adjust in concert with changes in population status or trend.
    There are no Statewide harvest quotas in Alaska; however, some 
local harvest management programs have been developed. Round Island, 
within the Walrus Island State Game Sanctuary, was a traditional 
hunting area of several Bristol Bay communities prior to the 
development of the game sanctuary. Access to Round Island is controlled 
by the State of Alaska via a permit system. To continue the traditional 
hunt, the local communities proposed a cooperative agreement, which 
resulted in a quota of 20 walrus and a 40-day hunting season in the 
fall (Chythlook and Fall 1998, p. 5). The management agreement was 
negotiated by the Service, Bristol Bay Native Association/Qayassiq 
Walrus Commission, the Eskimo Walrus Commission, and Alaska Department 
of Fish and Game (ADFG), and sanctioned in a signed memorandum of 
understanding. The State of Alaska issues hunting access permits only 
during the open season. If the quota is reached, additional hunting 
access could be denied and existing permits could be revoked. Recent 
harvests at Round Island have ranged from zero to two walruses per 
year. No walrus were harvested on Round Island in 2009 or 2010. Bristol 
Bay hunters also hunt elsewhere in the area without restriction, and 
may be shifting hunting efforts to islands outside the State game 
sanctuary as the monetary cost of traveling to Round Island is often 
prohibitive.
    With an interest in reviving traditional law, advancing the idea of 
self-regulation of the subsistence harvest, and initiating a local 
management infrastructure due to concern about changing sea-ice 
dynamics and the walrus population, the Native Villages of Gambell and 
Savoonga on St. Lawrence Island have recently formed Marine Mammal 
Advisory Committees (MMAC), and implemented local ordinances 
establishing a limit of four walruses per hunting trip. Walruses that 
are struck and lost (wounded and not retrieved), as well as calves, do 
not count against this limit. In addition, there is no limit on the 
number of trips, so the effectiveness of this ordinance in limiting 
total harvest is dependent on the total number of hunting trips. 
Factors such as subsistence needs, social mores, distance of walrus 
from the village, weather, success of previous trips, needs of 
immediate and extended family members, and monetary cost of making a 
trip all play a part in the number of trips a hunting party makes. The 
spring hunting season of 2010 was

[[Page 7656]]

the first to have the trip-limit ordinances in place. We estimate that 
91 percent of the hunting trips were in compliance with the ordinance 
by taking no more than four adult/subadult walrus per trip (Service, 
unpublished data).
    Subsistence harvest reporting in the United States is required 
under section 109(i) of the MMPA, and is administered through a 
Marking, Tagging, and Reporting Program (MTRP) codified at 50 CFR 
18.23(f). The MTRP requires Alaska Native hunters to report the harvest 
of walrus and present the ivory for tagging within 30 days of harvest. 
The Service also administers the Walrus Harvest Monitor Project (WHMP), 
which is an observer-based data-collection program conducted in the 
communities of Gambell and Savoonga during the spring harvest. This 
program is designed to collect harvest data and biological samples. Not 
all harvest in the United States is reported through the MTRP 
(regulatory program). The Service uses the WHMP (observer-based) 
harvest data to supplement MTRP data to develop a correction factor for 
noncompliance to estimate the number of walrus harvested, but not 
reported through the MTRP. The MTRP-reported harvest data (Statewide) 
is corrected for noncompliance (unreported harvest), and that total is 
then corrected to account for animals struck and lost (estimated at 42 
percent of the walrus that are shot). Current accuracy of the struck 
and lost estimate is unknown and should be re-estimated (USFWS 2010, p. 
4). Compliance rates with the MTRP vary considerably from year to year, 
with estimates ranging from a low of 60 percent to a high of 100 
percent.
    Subsistence harvest in Chukotka, Russia, is controlled through a 
quota system. An annual subsistence quota is issued through a decree by 
the Russian Federal Fisheries Agency. Quota recommendations are based 
on sustainable removal levels (approximately 4 percent of the 
population based on population and productivity estimates) (Garlich-
Miller and Pungowiyi 1999 p. 32). Because the population is shared with 
the United States, Russian quota recommendations have generally been 2 
percent or less of the estimated total population (Garlich-Miller and 
Pungowiyi 1999, p. 32; Kochnev 2010, pers. comm.). Russian harvest 
quotas are set annually and recent quota reductions in Russia of 
approximately 57 percent from 2003-2010 have been in response to a 
presumed population decline based in part on observed haulout 
mortalities from trampling and results from various population surveys. 
According to Kochnev (2004, p. 286), all the Pacific walrus haulouts of 
the Arctic coast of Chukotka, Russia, are characterized by a high 
disturbance level. The majority of these haulouts in Chukotka are near 
coastal villages, and used by local subsistence hunters (Kochnev 2004, 
p. 286).
    The harvest reporting program in Russia is administered by the 
Russian Agricultural Department. The harvest in Russia has been 
traditionally conducted by hunting teams from each village. Team 
leaders are required to submit two harvest reports per month. However, 
walrus hunting by individual hunters (those not part of a harvest team) 
has increased since the inception of the Russian Federation, and there 
is no official mechanism for individuals to report their harvest; as a 
result, Russian harvest estimates are biased low to an unknown degree 
(Kochnev 2010, pers. comm.). In addition, the Russians do not adjust 
their harvest estimates for animals that are struck and lost. The 
Service assumes that the Russian struck and lost rate is comparable to 
the U.S. rate, and applies the struck and lost correction factor of 42 
percent to the Russian harvest data when estimating total subsistence 
harvest levels. This correction provides a more accurate estimate of 
the number of animals removed from the population due to harvest.
    Subsistence removals of walrus in the United States are closely 
tied to social and traditional customs, subsistence needs, sea-ice 
dynamics, weather, and monetary costs related to hunting. We predict 
that the range-wide walrus population will be smaller in the future, 
due to changes in summer sea-ice cover and associated impacts; thus, 
fewer walrus overall will be available for harvest. However, in the 
Bering Strait region, winter and spring sea ice is expected to persist 
through mid-century; walrus will likely continue to be locally abundant 
in numbers that would enable harvest to continue at levels similar to 
current ones, over time. Because these animals would be available to 
local subsistence hunters around St. Lawrence Island and other Bering 
Strait villages, the Pacific walrus would remain an important 
subsistence resource. Subsistence harvest of walrus is extremely 
important to several Alaska Native cultures. The primary factor 
influencing the number of walrus harvested each year will be the 
general availability of walruses in the Bering Strait region.
    Given current and projected sea-ice conditions, and without 
additional Tribal, State or Federal hunting regulations to limit or 
restructure the harvest, we do not expect harvest pressure in the 
Bering Strait region to change appreciably in the foreseeable future 
(Garlich-Miller et al. 2011, Section 3.3.1.4.1 ``Climate Change''). The 
St. Lawrence Island Tribal Governments and subsistence hunters have 
recently taken steps to modify their harvest patterns through the 
formation of Marine Mammal Advisory Committees, and the adoption of 
local ordinances limiting the number of walrus harvested per hunting 
trip by Tribal members. These are substantial efforts on the part of 
the Tribes and subsistence hunters, and the Service looks forward to 
continuing to work through the co-management structure (which allows 
for cooperative efforts between the Service, Alaska Natives, and State 
agencies; MMPA sec. 119(b)(4)) to ensure that the harvest of the 
Pacific walrus remains sustainable for future generations. However, the 
current measures to regulate the subsistence harvest do not limit the 
harvest of females or provide limits on the total number of walruses 
harvested and, therefore, are not wholly sufficient to ensure that 
harvest in the Bering Strait region will be sustainable long term. The 
tribal ordinances are structured in such a way that the Marine Mammal 
Advisory Committees could enact additional regulations in the future to 
address efficiency (reduce the number of animals that are struck and 
lost), restructure the sex ratio of the harvest, or impose quotas upon 
their Tribal members, or enact other measures to manage the harvest.
    In the Bristol Bay and the Yukon-Kuskokwim regions of Alaska, 
levels of subsistence harvest of walrus may decline slightly, in light 
of declines in southern Bering Sea ice in the winter (subsistence 
hunters search for walrus that are resting on ice floes) and a recent 
trend of fewer male walrus remaining in Bristol Bay during the summer. 
However, harvest in these regions is already so low--averaging 5 and 18 
walrus reported as harvested per year, respectively, for 2004 through 
2008 (Service, unpublished data)--that it likely does not have an 
appreciable effect on the population. Future harvest patterns and 
levels are not anticipated to change significantly in either region 
(Garlich-Miller et al. 2011, Section 3.3.1.4.1 ``Climate Change'').
    In the North Slope region of Alaska, reported subsistence harvest 
averaged 48 walrus per year from 2004-2008. As summer sea ice in the 
Chukchi Sea recedes out over deep arctic basin waters, it is 
anticipated that coastal haulouts will form along the Chukchi coast 
into the foreseeable future. Large

[[Page 7657]]

concentrations of walrus on shore for longer periods of time could 
afford opportunity for additional harvest. The potential for hunting 
activity to create a stampede resulting in injuries or mortalities, or 
to displace animals from preferred forage areas (Kochnev 2004, p. 285) 
is of greater concern than the direct mortalities associated with 
harvest. Although the potential for increased harvest exists, we do not 
expect the harvest to increase based on the fact that these 
communities' subsistence focus is on bowhead and beluga whales, due to 
a strong cultural connection and tradition as a whaling culture. North 
Slope coastal communities also have access to a wider array of 
resources than island communities and rely much more heavily on other 
marine mammals, seabirds, fish and terrestrial mammals to meet their 
subsistence needs (MMS 2007, p. IV-186). Due to the presence of the oil 
industry, North Slope communities also have a stronger economic base 
than the Bering Strait communities, and therefore do not rely as 
heavily on ivory carving as a source of cash in the local economy.
    As stated above, barring additional Tribal or Federal regulations 
governing harvest, we predict that subsistence harvest is likely to 
continue at or near current levels, even as the walrus population 
declines in response to loss of summer sea ice. This is because walrus 
are expected to continue to remain locally abundant and available for 
subsistence harvest in the Bering Strait region in the winter and 
spring. Over time, depending on how quickly the population declines, 
future harvest levels will need to be reduced as population size 
declines, or subsistence harvest will become unsustainable. Therefore, 
we have determined that if subsistence harvest continues at current 
levels, as expected, it represents a threat to the walrus population in 
the foreseeable future. Although it is difficult to quantify 
sustainable removal levels because of the lack of information on 
Pacific walrus population status and trends, we have determined that 
the current harvest of approximately 4 percent is at a sustainable 
level based on a minimum population estimate of 129,000. Therefore, we 
do not consider the current level of subsistence harvest to be a threat 
to Pacific walrus at the present time. Our identification of 
subsistence harvest as a threat to the species in the foreseeable 
future is tied to expected population declines related to threats 
associated with reduced summer sea ice, and is based on the best 
scientific and commercial data available, including scientific 
projections to the end of the 21st century.
    Although we have suggested that overall harvest must adjust with 
population size, there are strategies other than a numerical quota that 
could be utilized in an effort to assure sustainability over the long 
term. The co-management structure and the St. Lawrence Island Tribal 
ordinances provide an effective means to address improvements in 
hunting efficiency, and modification of the sex structure of the 
harvest. Improving hunting efficiency by reducing the number of animals 
which are struck and lost could potentially reduce the total number of 
walrus removed from the population due to subsistence harvest. Adult 
breeding-age females are the most important cohort of the population. 
An overall reduction in the number of females removed annually while 
still allowing an unlimited number of males to be harvested has had a 
positive effect on a declining population in the past and could be an 
effective means of managing harvests for sustainability into the 
future.
    Our conclusion that subsistence harvest is a threat in the 
foreseeable future is supported by the BN models prepared by the 
Service and USGS. The sensitivity analyses of both models identified 
subsistence harvest as one of the major drivers of model predictions. 
The two models involved different assumptions relative to subsistence 
harvest levels. In the Service model, we assumed, for the reasons 
described above, that subsistence harvest levels would remain 
relatively constant over time, even as the walrus population declined 
in response to reduced sea-ice conditions. In the USGS model, Jay et 
al. (2010b, p. 15) assumed that future harvest rates would be 
proportional to walrus population size. However, these authors 
acknowledge that if in the future, the walrus population declines, but 
harvest continues at the current level, the population-level stress 
caused by the harvest would effectively increase (Jay et al. 2010b, p. 
16), thereby amplifying the impact of subsistence harvest on the 
population. In the Service model, maintaining the harvest at 
replacement levels (sustainable) reduced the probabilities of negative 
effects by about 19 percent compared to a higher harvest (Garlich-
Miller et al. 2011, Table 8). Results from the USGS model suggest that 
although minimizing harvest from current levels may have little 
positive effect on population outcomes in the future, harvests of high 
(greater than 4 percent of the population) and very high levels 
(greater than 6 percent) could add significantly to the adverse effects 
of future sea-ice conditions on population outcomes through the end of 
the century (Jay et al. 2010b, p. 16).
Summary of Factor B
    As discussed above, scientific and educational utilization of 
walruses is currently at low levels, regulated both domestically and in 
the Russian Federation, and is not a threat to the Pacific walrus now 
or in the foreseeable future. Recreational (sport) hunting of Pacific 
walrus is prohibited under the MMPA and by Russian legislation; 
therefore, it is not a threat to the Pacific walrus now or in the 
foreseeable future. United States import/export is not a threat to the 
Pacific walrus now or in the foreseeable future because Pacific walrus 
specimens exported from or imported into the United States consist 
mostly of fossilized bone and ivory shards, and any other walrus ivory 
can only be imported into or exported from the United States after it 
has been legally harvested and substantially altered to qualify as a 
Native handicraft. Commercial hunting of Pacific walrus in the United 
States is prohibited under the MMPA. Commercial hunting in Russia has 
not occurred since 1991 and could not resume unless a harvest quota 
based on sustainability were established; therefore, it is unlikely 
that Russian commercial harvest will be a threat to the Pacific walrus 
population.
    Over the past 50 years, Pacific walrus population annual harvest 
removals have varied from 3,200 to 16,000 per year. Over the past 
decade, subsistence harvest removals in the United States and Russia 
have averaged approximately 5,000 per year. Recent harvest levels are 
significantly lower than historical highs, although the lack of 
information on population status and trend make it difficult to 
quantify sustainable removal levels. Anticipated reductions in 
population size in response to losses in sea-ice habitats and 
associated impacts underscore the need for reliable population 
information as a basis for evaluating the sustainability of future 
harvest levels. Research leading to a better understanding of 
population responses to changing ice conditions and modeling efforts to 
examine the impact of various removal levels are currently under way by 
USGS and others.
    Subsistence harvest levels in Russia are presently controlled under 
a quota system based upon the 2006 population estimate. The Russian 
quota has been reduced recently in response to the loss of several 
thousand calves at terrestrial haulouts as a result of trampling events 
in recent years and their belief that the

[[Page 7658]]

population is in decline. Although the subsistence walrus harvest in 
Alaska is not regulated under a quota system, the MMPA provides for the 
development of voluntary co-management agreements with Alaska Native 
organizations. Notably, hunting ordinances were implemented in 2010 in 
Alaska's two primary hunting communities, providing a promising 
mechanism for self regulation of harvests. While it is premature to 
evaluate the efficacy of such local ordinances over the long term, the 
recent establishment of these local management programs offers a 
tangible framework for additional harvest management, as necessary. The 
existing harvest reporting and monitoring programs provide information 
on harvest program effectiveness and also provide data on harvest 
trends and composition. In conjunction with information on population 
status and trends, this information will be used to evaluate future 
harvest management strategies. Additionally, a multi-party agreement 
between the Service, State of Alaska, and two Alaska native groups 
includes a defined hunting season and a quota for the Round Island 
State Game Sanctuary.
    We wish to underscore the importance of the efforts the Alaska 
Native community has undertaken to manage subsistence harvest, and we 
are hopeful that community-based harvest regulations to improve 
efficiency (reduce animals that are struck and lost), adjust the sex 
structure of the harvest (reduce the overall take of females), or limit 
the total number of walrus taken will be developed in the future. The 
Service prefers to develop community-based harvest regulations. To that 
end, we will continue working directly with the subsistence hunting 
community and the Eskimo Walrus Commission to continually refine 
harvest monitoring and reporting and to share information on population 
status and trend from both traditional ecological knowledge and western 
science. We recognize that to improve our ability to manage the walrus 
harvest, the refinement of methods to estimate walrus abundance and 
trend, productivity, and habitat carrying capacity is needed. Our 
longstanding co-management agreement between the Service and the Eskimo 
Walrus Commission provides an important forum for continued dialogue 
about these harvest-related issues and a mechanism for developing 
further harvest management options.
    In summary, although the Service supports efforts by subsistence 
communities to implement voluntary programs with the goal of 
sustainable Pacific walrus harvests, we acknowledge that there are 
currently no regulatory mechanisms in place to assure the 
sustainability of subsistence harvests. In the absence of such 
regulatory mechanisms, we do not expect harvest levels in the Bering 
Strait region to change appreciably in the foreseeable future. 
Subsistence harvest is predicted to continue at similar levels, 
independent of future walrus population trends. Barring additional 
Tribal or Federal harvest management actions, we anticipate that the 
proportion of animals harvested will increase relative to the overall 
population, and this continued level of subsistence harvest will become 
unsustainable. Therefore, although we do not identify current 
subsistence harvest as a threat to the walrus population at the present 
time, we have determined that this continued level of subsistence 
harvest will become a threat to the walrus population, as it declines 
in the foreseeable future. Based on the best scientific and commercial 
data available, we find that overutilization in the form of subsistence 
harvest at current levels, is likely to threaten the Pacific walrus in 
the foreseeable future.

Factor C. Disease or Predation

    Future disease and predation dynamics may be tied to environmental 
changes associated with changes in sea ice and other environmental 
parameters that influence disease vectors and exposure, and predation 
opportunities. Our ability to reliably predict the potential level and 
influence of disease and predation is tied to our ability to predict 
environmental change and is related to our understanding of sea-ice 
dynamics. Under Factor A, we also discussed the potential increase in 
predation by polar bears associated with increasing dependence of 
Pacific walrus on coastal haulouts caused by the loss of sea-ice 
habitat.
Disease
    Infectious viruses and bacteria have the capacity to impact marine 
mammals, particularly when first introduced to a population (Duignan et 
al. 1994, p. 90; Osterhaus et al. 1997, p. 838; Ham-Lamme et al. 1999, 
p. 607; Calle et al. 2002, p. 98; Burek et al. 2008, p. 129). Pacific 
walrus have had exposure to several pathogens, such as Caliciviruses 
(Fay et al. 1984, p. 140; Smith et al. 1983, p. 86; Barlough et al. 
1986, p. 166), Leptospirosis (Calle et al. 2002, p. 96), and Influenza 
A virus (Calle et al. 2002, p. 95-96), none of which have resulted in 
large die-offs of animals.
    Additionally, the introduction of new viruses to populations of 
marine mammals may be the result of changing distribution patterns of 
the host (Duignan et al. 1994, p. 90; Dobson and Carper 1993; p. 1096). 
For example, phocine distemper virus (PDV) was recently found in the 
North Pacific (Goldstein et al., 2009 p. 2009), and while antibodies to 
PDV have been found in Atlantic walrus (Duignan et al. 1994, p. 90; 
Nielson et al. 2000, p. 510), as yet there has been no evidence of 
exposure in Pacific walruses.
    Parasites are common among pinnipeds, and their infestations result 
in various effects to individuals and populations, ranging from mild to 
severe (Fay 1982, p. 228; Dubey 2003, p. 275). For example, the 
ectoparasite Antarctophthirus trichchi is an anopluran (sucking) louse 
that lives in the skin folds of walruses (Fay 1982, p. 228), causing 
external itching, but no serious health issues (Fay 1982, p. 228).
    Endoparasites, protozoa, and helminthes (microorganisms and 
parasitic worms) also may impact populations, as they rely on locating 
suitable hosts to complete all or part of their life cycle. Of the 17 
species of helminthes known to parasitize Pacific walrus, 2 species are 
endemic (Fay 1982, p. 228; Rausch 2005, p. 134): The cestode 
Diphyllobothrium fayi, found only in the small intestine, and the 
nematode Anisakis rosmari, found only in stomachs (Heptner and Naumov 
1976, p. 52).
    Trichinella spiralis nativa (Rausch et al. 2007, p. 1249) infects 
Pacific walruses at a rate of about 1.5 percent (Bukina and Kolevatova 
2007, p. 14). While the possibility of contracting Trichinosis from 
infected walrus has been an issue of concern to some subsistence 
hunters for decades, Trichinella does not appear to cause any ill 
effects in walrus (Rausch et al. 2007, p. 1249).
    The intracellular parasite Toxoplasma gondii is a significant cause 
of encephalitis in sea otters and harbor seals (Dubey et al. 2003, p. 
276), and heart, liver, intestine and lung lesions in sea lions (Dubey 
et al. 2003, p. 281). It has been isolated from at least 10 species of 
marine mammals, including walrus (Dubey et al. 2003, p. 278). Of the 53 
Pacific walruses tested between 1976 and 1998, about 5.6 percent were 
positive for T. gondii (Dubey et al. 2003, p. 278). T. gondii has also 
been documented in some walrus prey (e.g., seals and bivalves; Fay 
1982, p. 146; Lowry and Fay 1984, p. 12; Dubey et al. 2003, p. 278; 
Lindsay et al. 2004, p. 1055; Jensen et al. 2009, p. 1); however, it 
will not likely play a significant role in the health of the Pacific 
walrus population, because they have a history

[[Page 7659]]

of exposure and no large walrus mortality events have been attributed 
to this organism.
    Neospora caninum is a protozoan parasite that was found in 3 of 53 
walruses (Dubey et al. 2003, p. 281). The health implication for N. 
caninum exposure in walruses is unknown, but the potential for exposure 
appears low.
    In summary, the occurrence and effects of diseases and parasites on 
Pacific walrus appear to be minor in terms of potential population-
level effects. Several diseases and parasites appear at chronically low 
levels; however, no outbreaks resulting in large die-offs have been 
observed. A changing climate may increase exposure of walrus to new 
organisms. Additionally, increased use of terrestrial haulouts may 
escalate the risk of transmission of disease (Fay 1974, p. 394). This 
potential stressor is part of the USGS Bayesian network model, which 
linked lower-shelf ice availability to walrus crowding and incidence of 
disease and parasites in the population, by increasing the walrus 
haulout sizes and concentrating their locations (Jay et al. 2010b, p. 
9). However, sensitivity analysis did not identify disease and 
predation as having a significant effect on model outcomes (Jay et al. 
2010b, p. 86). In addition, increased exposure to disease or parasites 
has yet to be documented, and there are no clear transmission vectors 
that would change the level of exposure. At this time, disease and 
parasites are not considered to be threats to the Pacific walrus 
population, and no evidence exists that they will be in the foreseeable 
future.
Predation
    Because of their large size and formidable tusks, adult walruses 
have few natural predators. Polar bears (Ursus maritimus) and killer 
whales (Orcinus orca) tend to prey on walruses only opportunistically 
and focus primarily on younger animals.
    However, when suitable sea-ice platforms are not available, Pacific 
walruses haul out onto land, where they become vulnerable to 
terrestrial predators and associated stampede events. Walrus carcasses 
accumulating at coastal haulouts provide scavenging opportunities that 
may attract bears (Ovsyanikov 2003, p. 13). Brown bears, wolverines, 
and feral dogs have also been observed scavenging at coastal haulouts 
in Chukotka, Russia, in recent years (Kochnev 2010, pers. comm.) and 
contribute to disturbances at these haulout sites. Programs have been 
established in recent years at some coastal haulouts in Chukotka, 
Russia, to mitigate disturbance-related mortalities that include 
collection of walrus carcasses and establishment of polar bear feeding 
areas away from the haulouts and villages (Kavry 2010, pers. comm.).
    The increase in walrus carcasses at coastal haulouts in Chukotka in 
recent years is likely playing an important role in shifting habitat-
use patterns of some polar bears and their progeny (Kochnev 2006, p. 
1). Walrus carcasses now represent an important food resource for polar 
bears on Wrangel Island in autumn and early winter (Kochnev 2002, p. 
137). Polar bears begin to appear near walrus haulouts on Wrangel 
Island in early August, about a month prior to the arrival of walruses 
(Kochnev 2002, p. 137). In the 1990s, the number of polar bears coming 
ashore on Wrangel Island peaked in late October, averaging 50 bears 
(Kochnev 2002, p. 137). However, in 2007, approximately 500-600 polar 
bears were stranded on Wrangel Island (Ovsyanikov and Menyushina 2007, 
p. 1), along with herds of walruses (up to 15,000 in one group); some 
of the walruses were in poor condition and polar bears were able to 
kill them relatively easily. At least 11 cases of polar bear predation 
on motherless calves were also observed (Ovsyanikov et al. 2007, p. 1).
    Because the summer/fall open-water period is projected to increase 
in the foreseeable future, polar bears are also predicted to spend more 
time on land. As a result, we anticipate that there will be greater 
interaction between the two species, and terrestrial walrus haulouts 
may become important feeding areas for polar bears. The presence of 
polar bears along the coast during the ice-free season will likely 
influence patterns of haulout use by walrus, and may play a significant 
role in the selection of coastal haulout sites (Garlich-Miller et al. 
2011, Section 3.4.2.1 ``Polar Bears''). We anticipate walrus to respond 
to this expected increase in interaction with polar bears by shifting 
to other coastal haulout locations. However, if walrus are forced to 
move to other locations to avoid predation by polar bears, the walrus 
may be displaced from preferred haulout locations with adequate prey 
resources to other areas that may or may not have less-suitable 
foraging habitat. It is also possible that walrus will be forced to 
move to different haulout locations more frequently, with increased 
energetic costs to them. Kochnev (2004, p. 286) asserted that when 
Pacific walrus migrate in autumn, from haulout to haulout on the Arctic 
coast of Chukotka, Russia, the increased pressure from humans and 
animal predators prevents walruses from getting adequate rest at the 
coastal haulouts, and some of the animals die in stampedes caused by 
disturbance events. The magnitude of these potential energetic costs 
would be determined by the frequency and distance of the shifts in 
location. Although predation by polar bears on Pacific walrus has been 
observed, no population-level effects have been documented to date; 
therefore, polar bear predation is not currently a threat to the 
Pacific walrus. As sea ice declines and Pacific walrus spend more time 
on coastal haulouts, however, it is likely that polar bear predation 
will increase. However, we cannot reliably predict the level of such 
predation. Although we have identified these issues as stressors for 
Pacific walrus, we are not able to conclude with sufficient reliability 
that they will rise to the level of a threat to the Pacific walrus 
population in the foreseeable future.
    Although sea-ice habitats also provide some protection against 
killer whales, which have limited ability to penetrate far into the ice 
pack, accounts of killer whale predation on walrus have been observed 
by Russian scientists and Alaskan Natives (Fay 1982, pp. 216-220). Some 
observers suggest that killer whales primarily prey upon the youngest 
animals, and instances of killer whale predation on adult walruses have 
also been documented (Fay and Stoker 1982, p. 2). The mortality from 
killer whale predation is unknown, but an interpretation of an 
examination of 52 walrus carcasses that washed ashore on St. Lawrence 
Island in 1951 (Fay 1982, p. 220) suggested that 17 walrus (33 percent) 
died from injuries consistent with killer whale predation. Fay and 
Kelly reported that 2 of 15 (13 percent) animals they examined had 
likely been killed by killer whales (Fay and Kelly 1980, p. 235). The 
potential for killer whales to expand their range and begin to target 
walruses at northern haulouts exists; however, this remains speculative 
at this time. Reduced availability of sea ice may lead to walruses 
spending more time in the water where they may be more susceptible to 
predation by killer whales (Boveng et al. 2009, p. 169). However, there 
is no evidence that killer whale predation has ever limited the Pacific 
walrus population, and there is no evidence of increased presence of 
killer whales in the Bering or Chukchi seas; therefore, killer whale 
predation is not a threat to the Pacific walrus now and is unlikely to 
be a threat in the foreseeable future.
    Sensitivity analyses of both BN models found that disease and 
predation had very little effect on model outcomes. For the Service 
model, disease and predation altered model

[[Page 7660]]

outcomes by 1.2 and 2.2 percent, respectively (Garlich-Miller et al. 
2011, Table 8). For the USGS model, disease and predation accounted for 
less than 1 percent of entropy (variation) reduction (Jay et al. 2010b, 
p. 85-86).
Summary of Factor C
    Disease and predation are not considered to represent threats to 
the Pacific walrus population at this time. Although a changing climate 
may increase exposure of walrus to new pathogens, there are no clear 
transmission vectors that would change levels of exposure, and no 
evidence exists that disease will become a threat in the foreseeable 
future. As walruses and polar bears become increasingly dependent on 
coastal haulouts, we expect interactions between the two species to 
increase. The presence of polar bears stranded along the coast during 
the ice-free season will likely influence patterns of haulout use and 
may play a significant role in the selection of coastal haulout sites. 
There is no evidence that killer whale predation has ever limited the 
Pacific walrus population, and there is no evidence of increased 
presence of killer whales in the Bering or Chukchi seas. The net effect 
of future predation levels on the population cannot be reliably 
predicted, because of uncertainties relative to distribution of walrus 
and their potential predators and the amount of potential overlap, and 
the degree to which these predators would target Pacific walrus. The 
best available scientific information indicates that the effect of 
predation on Pacific walrus may be a source of concern in the 
foreseeable future, particularly at the localized scale, where walrus 
congregate at coastal haulouts. However, we do not anticipate predation 
to be a threat to the entire population. Therefore, we conclude, based 
on the best scientific and commercial data available, that disease and 
predation are not threats to the Pacific walrus now, nor are they 
likely to become threats to the population in the foreseeable future.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    In determining whether the inadequacy of regulatory mechanisms 
constitutes a threat to the Pacific walrus, we focused our analysis on 
the specific laws and regulations aimed at addressing the two primary 
threats to the walrus-the loss of sea-ice habitat under Factor A and 
subsistence harvest under Factor B. These specific regulatory 
mechanisms are described below. Although none of the other stressors on 
walrus rise to the level of a threat, we also provide an overview of 
additional laws and regulations containing protective measures for the 
walrus.
Regulatory Mechanisms To Address Sea-Ice Loss
    As explained under Factor A, a primary threat to the survival of 
the Pacific walrus is the projected loss of sea-ice habitat due to a 
warming climate and its consequences for walrus populations. Currently, 
there are no regulatory mechanisms in place that effectively address 
GHG emissions, climate change, and associated sea-ice loss.
    National and international regulatory mechanisms to comprehensively 
address the causes of climate change are continuing to be developed. 
International efforts to address climate change began with the United 
Nations Framework Convention on Climate Change (UNFCCC), which was 
signed in May 1992. The UNFCCC states as its objective the 
stabilization of GHG concentrations in the atmosphere at a level that 
would prevent dangerous anthropogenic interference with the climate 
system, but it does not impose any mandatory and enforceable 
restrictions on GHG emissions. The Kyoto Protocol, negotiated in 1997, 
became the first agreement added to the UNFCCC to set GHG emissions 
targets for signatory counties, but the targets are not mandated. The 
Climate Change Act of 2008 established a long-term target to cut 
emissions in the United Kingdom (UK) by 80 percent by 2050 and by 34 
percent in 2020 compared to 1990 levels, but the law does not pertain 
to any emissions outside the UK. Other international laws, regulations, 
or other legally binding requirements imposing limits on GHG emissions 
to further the goals set forth in the UNFCCC and the Kyoto Protocol 
have not yet been adopted.
    In the United States, efforts to address climate change focus on 
the Clean Air Act and a number of voluntary actions and programs. 
Specifically, the Clean Air Act of 1970 (42 U.S.C. 7401 et seq.), as 
amended, requires the Environmental Protection Agency (EPA) to develop 
and enforce regulations to protect the general public from exposure to 
airborne contaminants hazardous to human health. In 2007, the Supreme 
Court ruled that gases that cause global warming are ``pollutants'' 
under the Clean Air Act, and that the EPA has the authority to regulate 
carbon dioxide and other heat-trapping gases (Massachusetts et al. v. 
EPA 2007 (Case No. 05-1120)). On December 29, 2009, the EPA adopted a 
regulation to require reporting of greenhouse gas emissions from fossil 
fuel suppliers and industrial gas suppliers, direct greenhouse gas 
emitters, and manufacturers of heavy duty and off-road vehicles and 
engines (EPA 2009, p. 56260). The rule does not actually regulate 
greenhouse gas emissions, however; but it merely requires that 
emissions above certain thresholds be monitored and reported (EPA 2009, 
p. 56260). On December 7, 2009, the EPA found that the current and 
projected concentrations of six greenhouse gases in the atmosphere 
threaten public health and welfare under section 202(a) of the Clean 
Air Act. This finding by itself does not impose any requirements on any 
industry or other entities to limit greenhouse gas emissions. While the 
finding could be considered a prerequisite for any future regulations 
developed by the EPA to reduce GHG emissions, no such regulations exist 
at this time. In addition, it is unknown whether any regulations will 
be adopted in the future as a result of the finding, or how effective 
such regulations would be in addressing GHG emissions and climate 
change.
Summary of Regulatory Mechanisms To Address Sea-Ice Loss
    Based on our analysis (above), we conclude that there are no known 
regulatory mechanisms in place at the national or international level 
that are likely to effectively reduce or limit GHG emissions. This 
conclusion is corroborated by the projections we used to assess risks 
to sea ice from GHG emissions, as described earlier in this finding. 
Therefore, the lack of mechanisms to regulate GHG emissions is already 
included in our risk assessment in Factor A, which shows that, without 
additional regulation, GHG emissions and corresponding sea-ice losses 
are likely to increase in the foreseeable future. Thus, we conclude 
that regulatory mechanisms do not currently exist to effectively 
address the loss of sea-ice habitat.
Regulatory Mechanisms To Ensure Harvest Sustainability
    While current harvest levels are considered sustainable, 
subsistence harvest has been identified as a threat to the Pacific 
walrus within the foreseeable future. As explained in Factor B, 
subsistence harvest is expected to continue at current levels, while 
the walrus population is projected to decline with the continued loss 
of sea ice and associated impacts. Barring additional Tribal or Federal 
regulations, we anticipate that the proportion of animals harvested 
will increase relative

[[Page 7661]]

to the overall population. As a result, the current level of 
subsistence harvest will likely become unsustainable in the foreseeable 
future. To address this threat, regulatory mechanisms will need to be 
developed and implemented to ensure that future harvest levels are 
reduced in proportion to the declining walrus population such that 
subsistence harvest levels are sustainable. To determine whether such 
regulatory mechanisms currently exist, we evaluated the various 
international and domestic laws and regulations, cooperative 
agreements, and local ordinances relevant to the subsistence harvest of 
walrus.
    In Russia, the Pacific walrus is a protected species managed 
primarily by the Fisheries Department within the Ministry of 
Agriculture. The subsistence harvest of walrus in Russia is authorized, 
but it is controlled through a quota system. Under the Russian ``Law on 
Fishery and Protection of Aquatic Biological Resources,'' the harvest 
of walrus is based upon the total annual catch (TAC) of walrus (Food 
and Agriculture Organization of the United Nations 2007, p. 4). The TAC 
takes into account the total population and productivity, based in part 
on the recommendations of scientists from the Pacific Research 
Fisheries Center (Chukotka Branch-ChukotTINRO) regarding a sustainable 
removal level (Kochnev, 2010 pers. comm.). The 2010 quota has been set 
at 1,300 animals (Kochnev, 2010 pers. comm.).
    In the United States, section 101(b) of the MMPA (16 U.S.C. 
1371(b)) provides an exemption for the continued nonwasteful harvest of 
walrus by coastal Alaska Natives for subsistence and handicraft 
purposes. Pursuant to Section 101(b)(3), regulations limiting the 
subsistence harvest of walrus may be adopted, but only if a 
determination is first made that the species or stock has been 
depleted, following notice and determination by substantial evidence on 
the record following an agency hearing before an administrative law 
judge. To date, no determination has ever been made that the species or 
stock has been depleted, and thus, no regulations establishing limits 
on the subsistence harvest of Pacific walrus in the United States have 
been adopted.
    Subsistence harvest reporting in the United States is required 
under section 109(i) of the MMPA. This requirement is administered 
through the Marking, Tagging, and Reporting Program (MTRP) and requires 
Alaska Native hunters to report the harvest of all walrus and present 
the ivory for tagging within 30 days of harvest. Since its 
implementation in 1988, the Service has used the program to improve its 
understanding of subsistence harvest by recruiting, training, and 
outfitting village residents to collect harvest data and tag tusks. 
Pursuant to the program, the Service has also maintained a walrus 
harvest reporting database and developed and implemented important 
outreach and education programs.
    In addition to the MTRP, the Service also administers the Walrus 
Harvest Monitoring Program, which is an observer-based data collection 
program conducted in the communities of Gambell and Savoonga during the 
spring harvest. The program is designed to collect basic biological 
information on harvested walrus, collect biological samples for 
research, and supplement the MTRP data set, to allow the Service to 
more accurately account for the unreported segment of the harvest. The 
Service law enforcement office simultaneously conducts an enforcement 
program designed to enforce the nonwasteful take provision of the MMPA.
    Some local harvest management programs have been adopted in 
addition to the above subsistence harvest data collection programs. 
Through a 1997 cooperative agreement between the Service, Bristol Bay 
Native Association/Qayassiq Walrus Commission, the Eskimo Walrus 
Commission, and ADFG, the subsistence harvest of walrus at Round 
Island, a traditional hunting area now located within the Walrus Island 
State Game Sanctuary, is restricted to a 40-day fall hunting season and 
a quota of 20 walrus (Chythlook and Fall 1998, pp. 4, 5). The harvest 
level in this area has ranged from zero to two per year and represents 
a very minor portion of the harvest in the United States.
    Similarly, out of a desire to revive traditional law, to advance 
the idea of self regulation of the subsistence harvest, and to initiate 
a local management infrastructure, the Native villages of Gambell and 
Savoonga on St. Lawrence Island have recently formed Marine Mammal 
Advisory Committees (MMAC) and implemented local ordinances 
establishing a limit of four walruses per hunting trip. The scope of 
these ordinances is limited, however, as walruses that are struck and 
lost and walrus calves do not count against this limit of four walruses 
per trip, and the number of trips is not restricted. Additionally, 
there is no quota on the total number of walruses that may be 
harvested.
Summary of Regulatory Mechanisms To Ensure Harvest Sustainability
    After evaluating the laws, regulations, cooperative agreements, and 
local ordinances described above, we conclude that adequate regulatory 
mechanisms are not currently in place to address the threat that 
continued levels of subsistence harvest pose to the Pacific walrus as 
the population declines in the foreseeable future. The Russian harvest 
is currently regulated with a quota system, based on the sustainability 
of the harvest. In Alaska, no Statewide quota exists. An annual quota 
does exist on Round Island, but the number of walrus harvested in this 
area is miniscule in relation to the overall harvest. In the Bering 
Strait Region, where the vast majority of U.S. harvest (84 percent) and 
43 percent of the rangewide harvest occurs, local ordinances recently 
adopted by two Native villages reflect the appreciation of the Native 
community for the important role of self-regulation in managing the 
subsistence harvest, and will serve as a starting point for future 
cooperative efforts and the development of harvest management 
strategies in the future. There are currently no tribal, Federal, or 
State regulations in place to ensure the likelihood that, as the 
population of walrus declines in response to changing sea-ice 
conditions, the subsistence harvest of walrus will occur at a reduced 
and sustainable level. As a result, we conclude that current regulatory 
mechanisms are inadequate to prevent subsistence harvest from becoming 
unsustainable in the foreseeable future. Therefore, we conclude that 
current regulatory mechanisms do not remove or reduce the threat to the 
Pacific walrus from future subsistence harvest.
Regulatory Mechanisms To Address Other Stressors
    A number of regulatory mechanisms directed specifically at 
protecting and conserving the walrus and its habitat are in place at 
the international, national, and local level. These mechanisms may be 
useful in minimizing the adverse effects to walrus from potential 
stressors other than sea-ice loss and subsistence harvest, such as the 
take of walrus for scientific or educational purposes, commercial 
harvest, human disturbance, and oil spills. Because none of these other 
stressors rise to the level of a threat to the Pacific walrus, we 
acknowledge that the protections discussed here are not essential to 
our determination of the adequacy of existing regulatory mechanisms to 
address threats to the walrus.

[[Page 7662]]

International Agreements
The Convention on International Trade in Endangered Species of Wild 
Fauna and Flora
    The Convention on International Trade in Endangered Species of Wild 
Fauna and Flora (CITES) is a treaty aimed at protecting species that 
are or may be affected by international trade. The CITES regulates 
international trade in animals and plants by listing species in one of 
three appendices. The level of monitoring and regulation to which an 
animal or plant species is subject depends on the appendix in which the 
species is listed. At the request of Canada, the walrus was listed at 
the species level in Appendix III, which includes species that are 
subject to regulation in at least one country, and for which that 
country has asked the other CITES Party countries for assistance in 
controlling and monitoring international trade in that species. For 
exportation of walrus specimens from Canada, an export permit may be 
issued by the Canadian Management Authority if it finds that the 
specimen was legally obtained. The import of walrus specimens into 
countries that are parties to CITES requires the presentation of a 
certificate or origin and, if the import was from Canada, an export 
permit. All countries within the range of the walrus--that is, the 
United States (Pacific walrus); the Russian Federation (Pacific and 
Laptev Walrus), Canada, Norway, Greenland (Denmark), and Sweden 
(Atlantic walrus) are members to the CITES and have provisions in place 
to monitor international trade in walrus specimens.
Domestic Regulatory Mechanisms
Marine Mammal Protection Act of 1972
    The Marine Mammal Protection Act of 1972, as amended (16 U.S.C. 
1361 et seq.) (MMPA) was enacted to protect and conserve marine mammals 
so that they continue to be significant functioning elements of the 
ecosystem of which they are a part. The MMPA sets forth a national 
policy to prevent marine mammal species or population stocks from 
diminishing to the point where they are no longer a significant 
functioning element of the ecosystems.
    The MMPA places an emphasis on habitat and ecosystem protection. 
The habitat and ecosystem goals set forth in the MMPA include: (1) 
Management of marine mammals to ensure they do not cease to be a 
significant element of the ecosystem of which they are a part; (2) 
protection of essential habitats, including rookeries, mating grounds, 
and areas of similar significance ``from the adverse effects of man's 
action''; (3) recognition that marine mammals ``affect the balance of 
marine ecosystems in a manner that is important to other animals and 
animal products,'' and that marine mammals and their habitats should 
therefore be protected and conserved; and (4) direction that the 
primary objective of marine mammal management is to maintain ``the 
health and stability of the marine ecosystem.'' Congressional intent to 
protect marine mammal habitat is also reflected in the definitions 
section of the MMPA. The terms ``conservation'' and ``management'' of 
marine mammals are specifically defined to include habitat acquisition 
and improvement.
    The MMPA established a general moratorium on the taking and 
importing of marine mammals, as well as a number of prohibitions that 
are subject to a number of exceptions. Some of these exceptions include 
take for scientific purposes, for purposes of public display, and for 
subsistence use by Alaska Natives, as well as unintentional take 
incidental to conducting otherwise lawful activities. The Service, 
prior to issuing a permit authorizing the taking or importing of a 
walrus, or a walrus part or product, for scientific or public display 
purposes, reviews each request, provides an opportunity for public 
comment, and consults with the U.S. Marine Mammal Commission (MMC), as 
described at 50 CFR 18.31. The Service has determined that there is 
sufficient rigor under the regulations at 50 CFR 18.30 and 18.31 to 
ensure that any activities so authorized are consistent with the 
conservation of this species and are not a threat to the species.
    Take is defined in the MMPA to include the ``harassment'' of marine 
mammals. ``Harassment'' includes any act of pursuit, torment, or 
annoyance that ``has the potential to injure a marine mammal or marine 
mammal stock in the wild'' (Level A harassment), or ``has the potential 
to disturb a marine mammal or marine mammal stock in the wild by 
causing disruption of behavioral patterns, including, but not limited 
to, migration, breathing, nursing, breeding, feeding, or sheltering'' 
(Level B harassment) (16 U.S.C. 1362(18)(A)).
    The MMPA contains provisions for evaluating and permitting 
incidental take of marine mammals, provided the total take would have 
no more than a negligible effect on the population or stock. 
Specifically, under Section 101(a)(5) of the MMPA, citizens of the 
United States who engage in a specified activity other than commercial 
fishing (which is specifically and separately addressed under the MMPA) 
within a specified geographical region may petition the Secretary of 
the Interior to authorize the incidental, but not intentional, taking 
of small numbers of marine mammals within that region for a period of 
not more than 5 consecutive years (16 U.S.C. 1371(a)(5)(A)). The 
Secretary ``shall allow'' the incidental taking if the Secretary finds 
that ``the total of such taking during each five-year (or less) period 
concerned will have no more than a negligible impact on such species or 
stock and will not have an unmitigable adverse impact on the 
availability of such species or stock for taking for subsistence uses'' 
(16 U.S.C. 1371(a)(5)(A)(i)). If the Secretary makes the required 
findings, the Secretary also prescribes regulations that specify: (1) 
Permissible methods of taking; (2) means of affecting the least 
practicable adverse impact on the species, their habitat, and their 
availability for subsistence uses; and (3) requirements for monitoring 
and reporting. (16 U.S.C. 1371(a)(5)(A)(ii)). The regulatory process 
does not authorize the activities themselves, but authorizes the 
incidental take of the marine mammals in conjunction with otherwise 
legal activities.
    Regulations authorizing the nonlethal incidental take of walrus 
from certain oil and gas activities in the Beaufort and Chukchi Seas 
are currently in place. These regulations are based on a determination 
that the effects of such activities, including noise, physical 
obstructions, human encounters, and oil spills, are likely to be 
sufficiently limited in time and scale that they would have no more 
than a negligible impact on the stock (USFWS 2008, pp. 33212, 33226). 
General operating conditions required to be imposed in specific 
authorizations include: (1) Restrictions on industrial activities, 
areas, and time of year; (2) restrictions on seismic surveys to 
mitigate potential cumulative impacts on resting, feeding, and 
migrating walrus; and (3) development of a site-specific plan of 
operation and a site-specific monitoring plan to enumerate and document 
any animals that may be disturbed. These and other safeguards and 
coordination with industry called for under the MMPA have been useful 
in helping to minimize industry effects on walrus.
    A similar process exists for the promulgation of regulations 
authorizing the incidental take of small numbers of marine mammals 
where the take will be limited to harassment (16 U.S.C. 1371(a)(5)(D)). 
These authorizations, referred to as Incidental Harassment 
Authorizations, are limited to 1 year and require a finding by the 
Department that the taking will have no more than a negligible impact 
on the species or stock

[[Page 7663]]

and will not have immitigable adverse impact on the availability of 
such species or stock for taking for subsistence uses. There are 
currently no incidental harassment authorizations in place for the 
walrus.
    As discussed under Factor E, shipping and anthropogenic noises are 
expected to increase in the Chukchi and Beaufort Seas in the future, 
and could impact the walrus or its habitat. Under the MMPA, however, 
disturbance of walrus from such otherwise lawful human activity is 
generally prohibited. While the MMPA does allow for the incidental 
taking of walrus, any such authorizations for increasing shipping 
activities or anthropogenic noise from industry would be required to be 
based on a determination that impacts to the Pacific walrus would be 
negligible and would not have an immitigable adverse impact on the 
availability of Pacific walrus for the taking for subsistence uses, 
consistent with the procedures outlined previously regarding the 
promulgation of take regulations and incidental harassment 
authorizations.
    Similarly, the potential for commercial fishing to expand into the 
Chukchi and Beaufort Seas could impact the Pacific walrus, as discussed 
later in this finding. However, the MMPA has protections in place to 
limit any potential incidental impacts of future commercial fisheries. 
Specifically, section 118 of the MMPA (16 U.S.C. 1387) calls for 
commercial fisheries to reduce any incidental mortality or serious 
injury of marine mammals to insignificant levels approaching zero. In 
its 2004 report to Congress regarding the commercial fisheries' 
progress toward reducing mortality and serious injury of marine 
mammals, the National Oceanic and Atmospheric Administration (NOAA) 
concluded that: (1) Most fisheries have achieved levels of incidental 
mortality consistent with the Zero Mortality Rate Goal; (2) substantial 
progress has been made in reducing incidental mortality through Take 
Reduction Plans; and (3) additional information will be needed for most 
fisheries and stocks of marine mammals to accurately assess whether 
mortality incidental to commercial fishing is at insignificant levels 
approaching a zero mortality and serious injury rate (NOAA 2004, 
Executive Summary). Thus, while commercial fishing could expand in the 
future, such expansions would need to be consistent with existing 
fisheries elsewhere in the United States that must limit their impacts 
to marine mammals.
Outer Continental Shelf Lands Act
    The Outer Continental Shelf Lands Act (OCSLA) (43 U.S.C. 331 et 
seq.) established Federal jurisdiction over submerged lands on the 
outer continental shelf (OCS) seaward for 5 km (3 mi) in order to 
expedite exploration and development of oil and gas resources. The 
OCSLA is implemented by the Bureau of Ocean Energy, Management, 
Regulation and Enforcement (formerly the Minerals Management Service) 
of the Department of the Interior. The OCSLA mandates that orderly 
development of OCS energy resources be balanced with protection of 
human, marine, and coastal environments. Specifically, Title II of the 
OCSLA provides for the cancellation of leases or permits if continued 
activity is likely to cause serious harm to life, including fish and 
other aquatic life. It also requires economic, social, and 
environmental values of the renewable and nonrenewable resources to be 
considered in management of the OCS. Through consistency 
determinations, any license or permit issued under the OCSLA must be 
consistent with State coastal management plans (see also the Coastal 
Zone Management Act below). Thus, the OCSLA helps to increase the 
likelihood that projects on the OCS do not adversely impact Pacific 
walruses or their habitats.
Oil Pollution Act of 1990
    The Oil Pollution Act of 1990 (OPA) (33 U.S.C. 2701) provides 
enhanced capabilities for oil spill response and natural resource 
damage assessment by the Service. The OPA requires the Service to 
consult on developing a fish and wildlife response plan for the 
National Contingency Plan, provide input to Area Contingency Plans, 
review Facility and Tank Vessel Contingency Plans, and conduct damage 
assessments for the purpose of obtaining damages for the restoration of 
natural resources injured from oil spills. However, we note that there 
are limited abilities to respond to a catastrophic oil spill event 
described in the plan (Alaska Regional Response Team 2002, pp. G-71, G-
72). The U.S. Coast Guard, despite planning efforts, has limited 
offshore capability to respond in the event of a large oil spill in 
northern or western Alaska, and we only marginally understand the 
science of recovering oil in broken ice (O'Rourke 2010, p. 23).
Coastal Zone Management Act
    The Coastal Zone Management Act of 1972 (CZMA) (16 U.S.C. 1451 et 
seq.) was enacted to ``preserve, protect, develop, and where possible, 
to restore or enhance the resources of the Nation's coastal zone.'' The 
CZMA provides for the submission of a State program subject to Federal 
approval. The CZMA requires that Federal actions be conducted in a 
manner consistent with the State's Coastal Zone Management Plan (CZMP) 
to the maximum extent practicable. Federal agencies planning or 
authorizing an activity that affects any land or water use or natural 
resource of the coastal zone must provide a consistency determination 
to the appropriate State agency. The CZMA applies to walrus habitats of 
northern and western Alaska. In Alaska, consistency determinations are 
reviewed for compliance with the Alaska Coastal Management Program 
(Alaska Stat. section 46.39-40). The Alaska Coastal Management Plan is 
developed in partnership with Alaska's natural resource agencies, the 
Alaska Department of Environmental Conservation, the ADFG, and the 
Department of Natural Resources (Alaska Coastal Management Plan 2005, 
p. A85). The CZMA applies to walrus habitats of northern and western 
Alaska by ensuring that any permitted actions are consistent with the 
State of Alaska's CZMP, which, among other things, sets standards that 
require exposed high energy coasts to be managed so as to avoid, 
minimize, or mitigate significant adverse impacts to the mix and 
transport of sediments. As such, these requirements provide potential 
protection to current or future coastal haulouts.
Alaska National Interest Lands Conservation Act
    The Alaska National Interest Lands Conservation Act of 1980 
(ANILCA) (16 U.S.C. 3101 et seq.) created or expanded National Parks 
and National Wildlife Refuges in Alaska, including the expansion of the 
Togiak National Wildlife Refuge (NWR) and the Alaska Maritime NWR. One 
of the purposes of these National Wildlife Refuges under the ANILCA is 
the conservation of marine mammals and their habitat. Walrus haulouts 
at Cape Peirce and Cape Newenham are located within Togiak NWR while 
haulouts at Cape Lisburne occur in the Alaska Maritime NWR. Access to 
the Cape Peirce is tightly controlled through a permitted visitor 
program. Refuge staff require that visitors must remain out of sight, 
downwind, and a minimum of 107 m (100 yards) from walruses. Visitors 
are advised that disturbances to walruses or seals are a violation of 
the MMPA (Miller 2010, pers. comm.). Cape Newenham has no established 
refuge visitor program, because public access is

[[Page 7664]]

extremely limited due to the presence of Department of Defense lands 
surrounding the Cape. As discussed under Factor A above, the change in 
the nature and location of walrus haulouts in response to changing ice 
conditions is anticipated into the foreseeable future. Significant 
portions of the Chukchi Sea coastal zone in Alaska are National 
Wildlife Refuge lands created under ANILCA, and they have the ability 
to provide haulout locations that are free from human disturbance.
Marine Protection, Research and Sanctuaries Act
    The Marine Protection, Research and Sanctuaries Act (MPRSA) (33 
U.S.C. 1401 et seq.) was enacted in part to ``prevent or strictly limit 
the dumping into ocean waters of any material that would adversely 
affect human health, welfare, or amenities, or the marine environment, 
ecological systems, or economic potentialities.'' The MPRSA does not 
itself regulate the take of walrus; however, it does help maintain 
water quality, which likely benefits walrus prey.
Magnuson-Stevens Fishery Conservation and Management Act
    The Magnuson Fishery Conservation and Management Act in 1976 
(renamed the Magnuson-Stevens Fishery Conservation and Management Act 
(MSFCMA)) (16 U.S.C. 1800 et seq.) established the North Pacific 
Fishery Management Council (NPFMC), one of eight regional councils 
established by the MSFCMA to oversee management of the U.S. fisheries. 
With jurisdiction over the 2,331,000-sq-km (900,000-sq-mi) Exclusive 
Economic Zone (EEZ) off Alaska, the NPFMC has primary responsibility 
for groundfish management in the Gulf of Alaska (GOA) and Bering Sea 
and Aleutian Islands (BSAI), including Pacific cod (Gadus 
macrocephalus), pollock, mackerel (Pleurogrammus monopterygius), 
sablefish (Anoplopoma fimbria), and rockfish (Sebastolobus and Sebastes 
species) species harvested mainly by trawlers, hook and line, 
longliners, and pot fishermen. In 2009, the NPFMC released its Fishery 
Management Plan for Fish Resources of the Arctic Management Area, 
covering all U.S. waters north of the Bering Strait. Management policy 
for this region is to prohibit all commercial harvest of fish until 
sufficient information is available to support the sustainable 
management of a commercial fishery (NPFMC 2009, p. 3). The policy helps 
to protect walrus from potential impacts of commercial fishery 
activities.
    Additionally, the Sustainable Fisheries Act of 1996 amended the 
MSFCMA, requiring the NOAA to describe and identify Essential Fish 
Habitat, which includes those waters and substrates necessary to fish 
for spawning, breeding, feeding, or growth to maturity. ``Waters'' 
include aquatic areas and their associated physical, chemical, and 
biological properties. ``Substrate'' includes sediment underlying the 
waters. ``Necessary'' means the habitat required to support a 
sustainable fishery and the managed species' contribution to a healthy 
ecosystem. Spawning, breeding, feeding, or growth to maturity covers 
all habitat types utilized by a species throughout its life cycle, and 
includes not only the water column but also the benthos layers. The 
NOAA's ``Final Rule for the implementation of the Fisheries of the 
Exclusive Economic Zone off Alaska; Groundfish Fisheries of the Bering 
Sea and Aleutian Islands Management Area,'' published July 25, 2008 
(NOAA 2008, p. 43362), protects areas adjacent to walrus haulouts and 
feeding areas from potential impacts of trawl fisheries. For example, 
the St. Lawrence Island Habitat Conservation Area closes waters around 
the St. Lawrence Island to federally permitted vessels using nonpelagic 
trawl gear. Such closures provide important refuge for the walrus, but, 
more importantly, protect feeding habitat from disturbance.
Russian Federation
    The walrus in Russia is a protected species managed primarily by 
the Fisheries Department within the Ministry of Agriculture. 
Regulations regarding the subsistence harvest of walrus were discussed 
previously. There is currently no commercial harvest of walrus 
authorized in Russia (Kochnev 2010, pers. comm.).
    Important terrestrial haulout sites in Russia are also protected, 
and human disturbance is minimized. For example, Wrangel Island, an 
area which has seen large influxes of walrus, as discussed above, has 
been a nature reserve since 1979 and prohibits human disturbance 
(United Nations Environmental Program 2005, p. 1). Additionally, the 
haulouts at Cape Kozhevnikov near the village of Ryrkaipyi and Cape 
Vankarem near the village of Vankarem were recently granted protections 
by the Government of Chukotka to minimize disturbance, and a local 
conservation organization known as the ``UMKY Patrol'' has organized a 
quiet zone and implemented visitor guidelines to reduce disturbance 
(Patrol 2008, p. 1; Kavry 2010, pers. comm.).
State of Alaska
    While the Service has the primary authority to manage Pacific 
walrus in the United States, the State of Alaska has regulatory 
programs that compliment Federal regulations and work in concert to 
provide conservation for walrus and their habitats. For example, as 
discussed above, the State's Coastal Zone Management Plan works to 
ensure that beach integrity is maintained. Additionally, oil and gas 
lease permits issued by the State of Alaska in State waters or along 
the coastal plain contain specific requirements for Pacific walrus 
that, for example, prohibit above-ground lease-related facilities and 
structures within 1 mile inland from the coast, in an area extending 1 
mile northeast and 1 mile southwest of the Cape Seniavin walrus haulout 
(ADNR 2005, p. 3). In addition, walrus and their habitats are protected 
in various State special-use areas. For example, the Walrus Island 
State Game Sanctuary is a State of Alaska-managed conservation area 
with regulations in place that allow only limited access to the 
sanctuary, prohibit any disturbance of walrus, and limit access to 
beaches and water. These regulations protect walrus and their haulouts 
(5 AAC 92.066, Permit for access to Walrus Islands State Game 
Sanctuary).
Summary of Factor D
    As explained in Factor A, the sea-ice habitat of the Pacific walrus 
has been modified by the warming climate, and sea-ice losses are 
projected to continue into the foreseeable future. There currently are 
no regulatory mechanisms in place to effectively reduce or limit GHG 
emissions. This situation was considered as part of our analysis in 
Factor A. Accordingly, there are no existing regulatory mechanisms to 
effectively address loss of sea-ice habitat.
    As explained in Factor B, harvest, while currently sustainable, is 
identified as a threat within the foreseeable future because we 
anticipate that harvest levels will continue at current levels while 
the population declines due to sea-ice loss; as a result, the 
proportion of animals harvested will increase. Harvest in Russia is 
managed for sustainability through a quota system. Harvest in the 
United States is well-monitored and limited to subsistence harvest by 
Alaska Natives, with further restrictions on use and sale of walrus 
parts; however, the U.S. harvest is not directly limited by quota. 
Emerging local harvest management efforts offer a promising approach to 
developing harvest management initiatives. Effectiveness of

[[Page 7665]]

such measures can be evaluated with existing harvest monitoring and 
reporting programs. In the Bering Strait Region, where the vast 
majority of U.S. harvest and 43 percent of the rangewide harvest 
occurs, local ordinances recently adopted by two Native villages 
reflect the important role of self-regulation in managing the 
subsistence harvest, and will be important in the development of 
harvest management strategies in the future. However, there are 
currently no tribal, Federal, or State regulations in place to ensure 
the likelihood that, as the population of walrus declines in response 
to changing sea-ice conditions, the subsistence harvest of walrus will 
occur at a reduced and sustainable level. As a result, we conclude that 
current regulatory mechanisms are inadequate to address the threat of 
subsistence harvest becoming unsustainable in the foreseeable future, 
as the Pacific walrus population declines due to sea-ice habitat loss 
and associated impacts.
    While laws and regulations exist that help to minimize the effect 
of other stressors on the Pacific walrus, there are no regulatory 
mechanisms currently in place that adequately address the primary 
threats of habitat loss due to sea-ice declines (Factor A) and 
subsistence harvest (Factor B). As a result, we conclude that the 
existing regulatory mechanisms do not remove or reduce the threats to 
the Pacific walrus from the loss of sea-ice habitat and 
overutilization.

Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence.

    We evaluated other factors that may have an effect on the Pacific 
walrus, including pollution and contaminants; oil and gas exploration, 
development, and production; commercial fisheries interactions; 
shipping; oil spills; and icebreaking activities. The potential effects 
of many of the stressors under this factor are tied directly to changes 
in sea ice. Potential increases in commercial shipping due to the 
opening of shipping lanes that have been unavailable in the past are 
one example. In addition, oil and gas exploration and development 
activities are in part dependent on ice conditions, as is the potential 
for expanding commercial fisheries. Because the potential effects of 
these stressors are related to sea-ice losses, our ability to reliably 
predict the potential level and influence of these stressors is tied to 
our ability to predict environmental changes associated with sea-ice 
losses, as discussed previously under Factor A.
Pollution and Contaminants
    Understanding the potential effects of contaminants on walruses is 
confounded by the wide range of contaminants present, each with 
different chemical properties and biological effects, and the differing 
geographic, temporal, and ecological exposure regimes. Nevertheless, 
Robards et al. (2009, p. 1) in their assessment of contaminant 
information available for Pacific walruses conclude that Pacific 
walruses contain generally low contaminant levels; however, an absence 
of data limited definitive conclusions about the effects current 
contaminant had on Pacific walruses.
    Of particular concern in the Arctic are persistent organic 
pollutants (POPs), because they do not break down in the environment 
and are toxic. ``Legacy'' POPs (those no longer used in the United 
States) include polychlorinated biphenyls (PCBs) and organochlorine 
pesticides such as DDT, chlordanes, toxaphene, and mirex. POPS with 
continued use include hexachlorocyclohexanes (HCHs). Although numerous 
POPs have been detected in the Arctic environment, concentrations of 
POPs found in Pacific walrus are relatively low (Seagars and Garlich-
Miller 2001, p. 129; Taylor et al. 1989, pp. 465-468) because walruses 
generally feed at relatively lower trophic levels than other marine 
mammals. In 1981, Atlantic walruses had the lowest concentrations of 
organochlorines in any pinniped measured (Born et al. 1981, p. 255), 
and recent data show walruses had much lower levels of brominated 
compounds and perfluorinated sulfonates (PFSA) than other Arctic marine 
mammals (Letcher et al., 2010, In press). Some Atlantic walrus 
individuals and populations specialize in feeding on pelagic fish and 
ringed seals, moving them higher in the food chain than the Pacific 
walrus, resulting in greater POP concentrations (Dietz et al. 2000, p. 
221). For example, PCBs and DDT concentrations in Pacific walruses were 
lower than concentrations found in Atlantic walruses from Greenland and 
Hudson Bay, Canada, collected in the 1980s (Muir et al. 1995, p. 335).
    Heavy metals of concern in Arctic marine mammals include mercury 
(Hg), cadmium, and lead. Defining mercury trends is complicated by 
mercury's complex environmental chemistry, although in general 
anthropogenic mercury is increasing in the Arctic, as it is globally 
(AMAP 2005, p. 17), primarily due to combustion processes. Temporally, 
mercury concentrations in fossils and fresh walrus teeth collected at 
Nunavut in the Eastern Canadian Arctic were no higher in the 1980s and 
1990s compared to A.D. 1200-1500, ``indicating an absence of industrial 
Hg in the species at this location.'' Increases of mercury were seen in 
beluga teeth from the Beaufort Sea over the same time span (Outridge et 
al. 2002, p. 123). There was also no change in mercury in walruses from 
Greenland from 1973 to 2000 (Riget et al. 2007, p. 76). Born et al. 
(1981, p. 225) found low methyl mercury accumulation in Atlantic 
walruses compared to seals in Greenland and the eastern Canadian 
Arctic.
    The presence of cadmium has been of concern to subsistence hunters 
who eat Pacific walruses, though it does not appear to be having 
effects on walrus health. Mollusks accumulate cadmium, so it is not 
surprising that walruses had relatively high levels. However, Lipscomb 
(1995, p. 1) found no histopathological (effects of disease on tissue) 
effects in Pacific walrus liver and kidney tissues, although liver 
concentrations were great enough to cause concern about contamination 
levels, walrus health, and the consumption of walrus. Over the time 
period 1981 to 1991, cadmium in Pacific walrus liver declined from 41.2 
to 19.9 milligrams/kg dry weight (Robards 2006, p. 24).
    Radionuclide (a radioactive substance) sources include atmospheric 
fallout from Chernobyl, nuclear weapons testing, and nuclear waste 
dumps in Russia (Hamilton et al. 2008, p. 1161). Pacific walrus muscle 
had non-naturally occurring cesium 137 levels lower than did bearded 
seals (Erignathus barbatus) sampled from the same area, and lower than 
seals from Greenland sampled one to two decades earlier (Hamilton et 
al. 2008, p. 1162). Barring new major accidents or releases, with decay 
of anthropogenic radionuclides from fallout and Chernobyl and improved 
regulation and cleanup of waste sources, radionuclide activities are 
expected to continue to decline in Arctic biota (AMAP 2009, p. 66).
    Tributyltin (TBT; from ship antifouling paints) is ubiquitous in 
the marine environment (Takahashi et al. 1999, p. 50; Strand and Asmund 
2003, p. 31), although TBT and its toxic metabolites are found at 
greatest concentrations in harbors and near shore shipping channels 
(Takahashi et al. 1999, p. 52; Strand and Asmund 2003, p. 34). Pacific 
walruses will likely see increased exposure to this contaminant class 
as shipping increases in their habitats as a result of longer ice-free 
seasons due to climate change.

[[Page 7666]]

    Climate-related change will affect long-range and oceanic transport 
of contaminants, and may provide additional sources of contaminants. 
Increasing water temperatures may increase methylation of mercury, 
which increases the availability of mercury for bioaccumulation 
(Sunderland et al. 2009, p. 1) and may release contaminants from 
melting pack ice (Metcalf and Robards 2008, p. S153). It is projected 
that Cesium 137 from nuclear weapons testing fallout and Chernobyl may 
be liberated from storage in trees as the incidence of forest fires 
increases due to climate change (AMAP 2009, p. 66).
    Although few data exist with which to evaluate the status of the 
Pacific walrus population in relation to contaminants, information 
available indicates that Pacific walruses have generally low 
concentrations of contaminants of concern. Further, based on the 
general observations of a lack of effect on individual animals, there 
is currently no evidence of population-level effects in walruses from 
contaminants of any type. Climate change, with projected increases in 
mobilization of contaminants to and within the Arctic, combined with 
potential changes in Pacific walrus prey base, may lead to increased 
exposure. However, potential effects are likely to be limited by the 
trophic status and distribution of walruses: As benthic feeders that 
specialize on prey lower in the food web, walruses would have a low 
rate of bioaccumulation and therefore limited exposure to contaminants. 
Based on our estimation of low current contaminant loads and the 
likelihood of minimal future exposure as walruses feed on lower trophic 
levels, we conclude that contaminants are not a threat now and are not 
likely to be a threat to the Pacific walrus population in the 
foreseeable future.
Oil and Gas Exploration, Development, and Production
    Oil and gas related activities have been conducted in the Beaufort 
and Chukchi Seas since the late 1960s, with most activity occurring in 
the Beaufort Sea (USFWS 2008, p. 33212). Three existing projects are 
located off the coast of Alaska in the Beaufort Sea (Endicott, 
Northstar, and Oooguruk). Current and foreseeable future activity in 
the Chukchi Sea is related to Lease Sale 193, the first Chukchi Sea 
lease sale since 1991 (MMS 2008, p. 1). While no development of leases 
issued pursuant to the lease sale has occurred to date, future activity 
is anticipated. Our ability to predict effects of these activities on 
walrus is based, in part, on reasonably foreseeable development 
scenarios prepared for this lease sale, which project exploration, 
development, and production activities to last through roughly 2049 
(USFWS, Final Biological Opinion for Beaufort and Chukchi Sea Program 
Area Lease Sales and Associated Seismic Surveys and Exploratory 
Drilling, Anchorage, Alaska, September 3, 2009, pp. 10-11).
    In the Chukotka Russia region, the oil and gas industry is 
targeting regions of the Bering and Chukchi Seas for exploration. 
Recently, there has been renewed interest in exploring for oil and gas 
in the Russian Chukchi Sea, as new evidence suggests that the region 
may harbor large reserves. In 2006, seismic exploration was conducted 
in the Russian Chukchi to explore for economically viable oil and gas 
reserves (Frantzen 2007, p. 1).
    Currently, Pacific walruses do not normally range into the Beaufort 
Sea, although individuals and small groups have been observed there. 
From 1994 to 2004, industry monitoring programs recorded a total of 9 
walrus sightings, involving a total of 10 animals. No disturbance 
events or lethal takes have been reported to date (USFWS 2008, p. 
33212). Because of the small numbers of walruses encountered by past 
and present oil and gas activity in the Beaufort Sea, impacts to the 
Pacific walrus population appear to have been minimal (USFWS 2008, p. 
33212). Even with less ice, it is unlikely that walrus numbers will 
increase significantly in the Beaufort Sea, as habitat is limited by a 
relatively narrow continental shelf, which results in deep and less-
productive waters. Therefore, we do not anticipate significant 
interactions with, or impacts from, oil and gas activities in the 
Beaufort Sea on the Pacific walrus population.
    Pacific walruses are seasonally abundant in the Chukchi Sea. 
Exploratory oil and gas operations in the Chukchi Sea have routinely 
encountered Pacific walruses; however, potential impacts to walruses 
are regulated through the MMPA. Specifically, incidental take 
regulations (ITRs) have been promulgated for the non-lethal, incidental 
take of walruses from oil and gas exploration activities in the Chukchi 
Sea, including geophysical, seismic, exploratory drilling and 
associated support activities for the 5-year period ending in June 
2013. In a detailed analysis of the effects of such activities, 
including noise, physical obstructions, human encounters, and oil 
spills, the Service concluded that exploration activities would be 
sufficiently limited in time and scope that they would result in the 
take of only small numbers of walruses with no more than a negligible 
impact on the stock (73 FR 33212 (2008)). Prior to commencing 
exploration activities, operators are currently required by the Bureau 
of Ocean Energy, Management, Regulation and Enforcement (BOEMRE, 
formerly MMS) to obtain letters of authorization (LOA) pursuant to the 
ITRs or an incidental harassment authorization (IHA) (Wall 2011, pers. 
comm.). If operators commence operations without such authorization, 
their operations may be shut down, (Wall 2011, pers. comm.), and any 
take of walrus would be in violation of the MMPA.
    While we anticipate oil and gas exploration activities to occur in 
the Chukchi Sea in the foreseeable future, we expect industry to 
request that the ITRs be renewed, so that any non-lethal, incidental 
take associated with exploration is authorized under the MMPA. The ITRs 
could not be renewed, and LOAs could not be issued, unless a 
determination were made that the activities would result in the take of 
only small numbers of walrus and have a negligible impact on the stock.
    Monitoring studies performed to date have documented minimal 
effects of various exploration activities on walruses (USFWS 2008, p. 
33212). In 1989 and 1990, aerial surveys and vessel-based observations 
of walruses were carried out to examine the animals' response to 
drilling operations at three Chukchi Sea prospects. Aerial surveys 
documented several thousand walruses (a small percentage of the 
estimated population) in the vicinity of the drilling prospects. The 
monitoring reports concluded that: (1) Walrus distributions were 
closely linked with pack ice; (2) pack ice was near active drill 
prospects for relatively short time periods; and (3) ice passing near 
active prospects contained relatively few animals. Walruses either 
avoided areas of operations or were passively carried away by the ice 
floes, and because only a small proportion of the population was near 
the operations, and for short periods of time, the effects of the 
drilling operations on walruses were limited in time, area, and 
proportion of the population (USFWS 2008, p. 33212). However, if walrus 
are forced to avoid areas of operations and associated disturbance by 
abandoning ice haulouts and swimming to other areas, they will likely 
experience increased energetic costs related to active swimming as 
opposed to passive transport on ice floes.
    Disturbances caused by vessel and air traffic may cause walrus 
groups to abandon land or ice haulouts. One study

[[Page 7667]]

suggests that walruses may be tolerant of ship activities; Brueggeman 
et al. (1991, p. 139) reported that 75 percent of walruses encountered 
by vessels in the Chukchi Sea exhibited no reaction to ship activities 
within 1 km (0.6 mi) or less. This conclusion is corroborated by 
another study, which reported observations that walruses in water 
generally show little concern about potential disturbance from 
approaching vessels and will dive or swim away if a vessel is nearing a 
collision with them (Fay et al. 1984, p. 118).
    Open-water seismic exploration, which produces underwater sounds 
typically with air gun arrays, may potentially affect marine mammals. 
Walruses produce a variety of sounds (grunts, rasps, clicks), which 
range in frequency from 0.1 to 10.0 Hertz (Hz, sine wave of a sound) 
(Richardson et al. 1995, p. 108). The effects of seismic surveys on 
walrus hearing and communications have not been studied. Seismic 
surveys in the Beaufort and Chukchi Seas will not impact vocalizations 
associated with breeding activity (one of the most important times of 
communication), because walruses do not currently breed in the open 
water areas that are subject to survey. Injury from seismic surveys 
would likely occur only if animals entered the zone immediately 
surrounding the sound source (Southall et al. 2007, p. 441). Walrus 
behavioral responses to dispersal and diving vessels associated with 
seismic surveys were monitored in the Chukchi Sea OCS in 2006. Based 
upon the transitory nature of the survey vessels, and the behavioral 
reactions of the animals to the passage of the vessels, we conclude 
that the interactions resulted in temporary changes in animal behavior 
with no lasting impacts to the species (Ireland et al. 2009, pp. xiii-
xvi).
    Future seismic surveys are anticipated to have minimal impacts to 
walrus. Surveys will occur in areas of open water, where walrus 
densities are relatively low. Monitoring requirements (vessel-based 
observers) and mitigation measures (operations are halted when close to 
walrus) in U.S. waters are expected to minimize any potential 
interactions with large aggregations of walruses. Because seismic 
operations likely would not be concentrated in any one area for 
extended periods, any impacts to walruses would likely be relatively 
short in duration and have a negligible overall impact on the Pacific 
walrus population.
    Currently, there are no active offshore oil and gas developments in 
the U.S. Bering or Chukchi Seas. Therefore, the risk of an oil spill is 
low at the present time. The potential for an oil spill increases as 
offshore oil and gas development and shipping activities increase. No 
large oil spills have occurred in areas inhabited by walruses; however, 
a large oil spill could result in acute mortalities and chronic 
exposure that could substantially reduce the Pacific walrus population 
for many years (Garlich-Miller et al. 2011, Section 3.6.2.3.3 ``Oil 
Spills''). A spill that oiled coastal haulouts occupied by females and 
calves could be particularly significant and could have the potential 
to impact benthic communities upon which walruses depend. As discussed 
below, oil spill cleanup in the broken-ice and open-water conditions 
that characterize walrus habitat would be more difficult than in other 
areas, primarily because effective strategies have yet to be developed. 
The Coast Guard has no offshore response capability in northern or 
western Alaska (O'Rourke 2010, p. 23).
    According to BOEMRE, if oil and gas development of leases issued 
pursuant to Chukchi Lease Sale 193 occurs, the chance of one or more 
large oil spills (greater than or equal to 1,000 barrels) occurring 
over the production life of the development is between 35 and 40 
percent (MMS 2007, p. IV-156). However, the estimated probability that 
oil reserves sufficient for development will be discovered range from 1 
to 10 percent (MMS 2007, p. IV-156), reducing the chance of a large oil 
spill to 0.33 to 4 percent.
    Our analysis of oil and gas development potential and subsequent 
risks was based on the analysis BOEMRE (MMS 2007, p. 1-631) conducted 
for the Chukchi Sea lease sales. Following the Deepwater Horizon 
incident in the Gulf of Mexico, offshore oil and gas activities have 
come under increased scrutiny. Policy and management changes are under 
way within the Department of the Interior that will likely affect the 
timing and scope of future offshore oil and gas activities. In 
addition, BOEMRE has been restructured to increase the effectiveness of 
oversight activities, eliminate conflicts of interest, and increase 
environmental protections (USDOI 2010, p. 1). As a result, we 
anticipate that the potential for a significant oil spill will remain 
small; however, we recognize that should a spill occur, there are no 
effective strategies for oil spill cleanup in the broken-ice conditions 
that characterize walrus habitat. In addition, the potential impacts to 
Pacific walrus from a spill could be significant, particularly if 
subsequent cleanup efforts are ineffective. Potential impacts would be 
greatest if walrus are aggregated in coastal haulouts where oil comes 
to shore. Overall, the chance of a large oil spill occurring in the 
Pacific walrus' range in the foreseeable future, however, is considered 
low.
    In summary, oil and gas activities have occurred sporadically 
throughout the range of the Pacific walrus. Specific studies on the 
effects of exploratory drilling activities and associated shipping and 
seismic surveys have documented minimal effects on walrus--namely, 
transitory behavioral changes that were temporary in nature. 
Exploration activities are currently regulated under the MMPA, and the 
take of walrus during exploration activities is only authorized if 
operators have first obtained an LOA or an IHA. These authorizations 
are only issued for the non-lethal, incidental take of walrus, where 
the activities are considered likely to result in the take of small 
numbers of walrus with a negligible impact on the stock. We expect that 
future exploration to be similarly regulated under the MMPA. Therefore, 
we conclude that impacts of oil and gas exploration likely to occur 
over the foreseeable future will have minimal effects on walruses. 
Further, although a significant oil spill in the Chukchi Sea from 
exploration, development or production activities could have a 
detrimental impact on Pacific walrus, depending on timing and location, 
the potential for such a spill is low. As a result, we conclude that 
oil and gas exploration, development, and production are not threats to 
the Pacific walrus now, nor are they likely to become threats in the 
foreseeable future.
Commercial Fisheries
    Commercial fisheries occur primarily in ice-free waters and during 
the open-water season, which limits the overlap between fishery 
operations and walruses. Where they do overlap, fisheries may impact 
Pacific walruses through interactions that result in the incidental 
take of walrus or through competition for prey resources or destruction 
of benthic prey habitat. A complete list of fisheries is published 
annually by NOAA Fisheries. The most recent edition (NOAA 2009a, p. 
58859), showed about nine fisheries that have the potential to occur 
within the range of the Pacific walrus.
    Currently, incidental take in the form of mortality from commercial 
fishing is low. Pacific walruses occasionally interact with trawl and 
longline gear of groundfish fisheries. In Alaska each year, fishery 
observers monitor a percentage of commercial fisheries and report 
injury and mortality of marine

[[Page 7668]]

mammals affected incidental to these operations. Incidental mortality 
to Pacific walruses during 2002-2006 was recorded for only one fishery, 
the Bering Sea/Aleutian Island flatfish trawl fishery, which is a 
Category II Commercial Fishery with 34 vessels or persons. During the 
years 2002-2006, observer coverage for this fishery averaged 64.7 
percent. The mean number of observed mortalities was 1.8 walrus per 
year, with a range of 0 to 3 walrus per year. The total estimated 
annual fishery-related incidental mortality in Alaska was 2.66 walrus 
per year (USFWS 2010, pp. 3-4).
    In addition to incidental take from fishing activities, however, 
fishery vessel traffic has the potential to take Pacific walruses 
through collisions and disturbance of resting, foraging, or travelling 
behaviors. We consider the likelihood of collisions between fishing 
vessels and walruses to be very low, however, as we unaware of any 
documented ship strikes, and it has been observed that walruses 
typically dive or swim off to the side if a shipping vessel comes close 
to colliding with them (Fay et al. 1984, p. 118). Fisheries occurring 
near terrestrial haulouts may affect animals approaching, leaving, or 
resting at the haulouts.
    The Bristol Bay region in the Bering Sea is home to some of the 
largest U.S. land haulouts and several fisheries. For some haulouts, 
regulations are in place to minimize disturbance. Round Island is 
buffered from all fishing activities by a 0-to-3-nautical-mile ``no 
transit'' closure. Capes Peirce and Newenham and Round Island are 
buffered from fishing activities in Federal waters from 3 to 12 
nautical miles; however, this buffer only applies to vessels with 
Federal fisheries permits. The haulout at Hagemeister Island has no 
protection zone in either Federal or State waters. Large catcher/
processer vessels associated with the yellowfin sole fishery, as well 
as smaller fishing vessels 32 ft or less in length routinely pass 
between the haulout and the mainland to a site for offloading product 
to foreign vessels. Anecdotal reports indicate potential disturbance of 
walruses using the Hagemeister haulout (Wilson and Evans 2009b, p. 28). 
To address concerns of disturbance associated with the yellowfin sole 
fleet, the Service has engaged the North Pacific Fisheries Management 
Council to examine alternatives to provide increased protection for the 
haulout at Hagemeister Island (Wilson and Evan 2009a, pp. 1-23); 
however, no specific measures have been implemented. The haulout at 
Cape Seniavin currently has no Federal or State protection zones. No 
Federal fisheries occur near Cape Seniavin, but State of Alaska-managed 
salmon fisheries do occur in the immediate vicinity and pose a 
potential for disturbance. In general, however, within Bristol Bay, the 
proportion of walruses potentially affected is small relative to the 
population. The population is also comprised predominantly of males, 
which are less susceptible to trampling injuries as a result of 
disturbance; however, repeated disturbance events have the potential to 
result in haulout abandonment.
    State-managed nearshore herring and salmon gillnet fisheries also 
have the potential to take walruses. The ADFG does not have an observer 
or self-reporting program to record marine mammal interactions, but it 
is believed that gear interactions with walruses have not occurred in 
the recent past (Murphy 2010, pers. comm.; Sands 2010, pers. comm.). 
Spotter planes used in the spring herring fishery in Bristol Bay have 
the potential to cause disturbance at terrestrial haulouts. To mitigate 
this potential, the Service developed and distributed guidelines for 
appropriate use of aircraft within the vicinity of Bristol Bay walrus 
haulouts (USFWS 2009, p. 1), and these were in effect during the 
fishing season.
    In summary, given the current low rates of walrus encounters and 
deaths associated with commercial fishing, we expect that any increase 
in the level of fishery-related mortality to walrus will occur at a 
very low level relative to the total walrus population. Similarly, 
although walrus may be subject to disturbance from commercial fishing, 
the proportion of walrus affected is low, and efforts are under way to 
minimize the impacts. Accordingly, we do not consider fishery-related 
take of walrus to be a threat to the Pacific walrus population now or 
in the foreseeable future.
    Commercial fisheries may also impact walruses through competition 
for prey resources or destruction of benthic prey habitat. With regard 
to competition, there is little overlap between commercial fish species 
and Pacific walrus prey species. The principal prey items consumed by 
weaned walruses are bivalves, gastropods, and polychaete worms (Fay 
1982, p. 145; Sheffield and Grebmeier 2009, p. 767). Fay (1982, pp. 
153-154) notes that the scarcity in walruses of endoparasites of known 
fish origin indicates that walruses rarely ingest fish. Fay (1982, pp. 
152,154) also notes that various authors have reported occasionally 
finding several different crab species in walrus stomachs, but 
apparently at low frequency. Thus, direct competition for prey from 
commercial fisheries does not appear to be a threat to the Pacific 
walrus population now or in the foreseeable future.
    Commercial fisheries--specifically pelagic (mid-water trawl) and 
nonpelagic (bottom trawl) fisheries--have the potential to indirectly 
affect walruses through destruction or modification of benthic prey or 
their habitat. Pelagic or mid-water trawls make frequent contact with 
the bottom, as evidenced by the presence of benthic species (e.g., 
crabs, halibut) that are brought up as bycatch. NFMS estimates that 
approximately 44 percent of the area shadowed by the gear receives 
bottom contact from the footrope (NMFS 2005, pp. B-11). The majority of 
the pelagic trawl effort in the eastern Bering Sea is directed at 
walleye pollock in waters of 50-300 m (164-960 ft) (Olsen 2009, p. 1). 
The area north of Unimak Island along the continental shelf edge 
receives high fishing effort (Olsen 2009, p. 1). This puts the majority 
of pelagic fishing effort on the periphery of walrus-preferred habitat, 
as walruses are usually found over the continental shelf in waters of 
100 m (328 ft) or less (Fay and Burns 1988, pp. 239-240; Jay et al. 
2001, p. 621).
    Nonpelagic fisheries also have the potential to indirectly affect 
walruses by destroying or modifying benthic prey or their habitat, or 
both. The predominant effects of nonpelagic trawl include ``smoothing 
of sediments, moving and turning of rocks and boulders, resuspension 
and mixing of sediments, removal of sea grasses, damage to corals, and 
damage or removal of epigenetic organisms'' (Mecum 2009, p. 57). 
Numerous studies on the effects of trawl gear on infauna have been 
conducted, and all note a reduction in mass (Brylinsky et al. 1994, p. 
650; Bergman and van Santbrink 2000, p. 1321; McConnaughey et al. 2000, 
p. 1054; Kenchington et al. 2001, p. 1043). Two such studies comparing 
microfaunal populations between unfished and heavily fished areas in 
the eastern Bering Sea reported that, overall, the heavily trawled and 
untrawled areas were significantly different. In relation to walrus 
prey, the abundance of neptunid snails was significantly lower in the 
heavily trawled area, and mean body size was smaller, as was the trend 
for a number of bivalve species (Macoma, Serripes, Tellina), indicating 
a general decline in these species. The abundance of Mactromeris was 
greater in the heavily trawled area, but mean body size was smaller 
(McConnaughey et al. 2000, pp. 1381-1382; McConnaughey et al. 2005, pp. 
430-431).

[[Page 7669]]

    The areas open to nonpelagic trawling, however, are limited. The 
Final Environmental Impact Statement (EIS) for Essential Fish Habitat 
Identification and Conservation in Alaska concluded that nonpelagic 
trawling in the southern Bering Sea has long-term effects on benthic 
habitat features, but little impact on fish stock productivity. The EIS 
concludes that the reduction of infaunal and epifanual prey for managed 
fish species would be 0 to 3 percent (NMFS 2005, p. 10; Mecum 2009, p. 
47). While not a direct measure of impacts to walrus prey, the analysis 
provides some insight on the level of impact to benthic species and 
indicates that impacts are likely to be minimal.
    Nonpelagic trawls are designed to remain on the bottom of the ocean 
floor, but they may bring up walrus prey items as bycatch, albeit in 
very small quantities. Wilson and Evans (2009, p. 15) report bycatch of 
walrus prey items in the nonpelagic trawl fishery in the Northern 
Bristol Bay Trawl Area (NBBTA). Data were collected through the NMFS 
Fisheries Observer program and are aggregated for the years 2001 to 
2009. Bivalves (mussels, oysters, scallops, and clams) accounted for 
334 kg (735 lb) of the 457 kg (1005 lb) (73 percent) of total bycatch 
reported; snails, which are consumed by walruses, were listed as a 
bycatch species, but no amounts were reported. This level of bycatch is 
very low relative to the total amount of prey consumed by walrus. The 
NMFS is currently developing regulations to require the use of modified 
nonpelagic trawl gear in the Bering Sea subarea for the flatfish 
fishery and for nonpelagic trawl gear fishing in the northern Bering 
Sea subarea (Brown 2010, pers. comm.), which will likely reduce impacts 
on walrus prey. When implemented, the regulations will reopen an area 
within the NBSRA to modified gear nonpelagic trawl fishing (Brown 2010, 
pers. comm.; Mecum 2009, pp. 1-194).
    Ecosystem shifts in the Bering Sea are expected to extend the 
distribution of fish populations northward and, along with this shift, 
nonpelagic bottom trawl fisheries are also expected to move northward 
(NOAA 2009b, p. 1). Because we currently lack information on benthic 
habitats and community ecology of the northern Bering Sea, we are 
unable to forecast the specific impacts that may occur from nonpelagic 
bottom trawling within this area (NOAA 2009b, p. 1) and how it may 
affect the Pacific walrus.
    Commercial fisheries in all U.S. waters north of the Bering Strait 
are covered by the Fishery Management Plan for Fish Resources of the 
Arctic Management Area, which was released by the NPFMC in 2009. 
Management policy for this region is to prohibit all commercial harvest 
of fish until sufficient information is available to support the 
sustainable management of a commercial fishery (NPFMC 2009, p. 3). At 
some point, the Arctic Management Area may be opened to commercial 
fishing, but to date the NPFMC has taken a conservative stance. It is 
unclear whether the Arctic Management Area will open to commercial 
fishing at all, and if so, when it would be opened. If commercial 
fishing does open up in this area, however, we would work with the 
NPFMC to ensure that any necessary measures to minimize negative 
effects to Pacific walrus are implemented.
    Accordingly, although commercial fisheries--specifically pelagic 
and nonpelagic trawl fisheries--have the potential to indirectly affect 
walruses through destruction or modification of benthic prey or their 
habitat, those fisheries do not appear to be a threat to Pacific walrus 
now or in the foreseeable future, because of limited overlap between 
the areas currently open to trawling and areas of walrus prey habitat 
as well as ongoing efforts to minimize detrimental impacts to walrus 
prey and benthic habitat.
    In summary, we find that commercial fisheries have limited overlap 
with walrus distribution, and reported direct takes are nominal. 
Indirect effects on walruses are also limited, with some site-specific 
potential effects to walrus near terrestrial haulouts in Bristol Bay. 
Indirect effects to prey and benthic habitats due to various types of 
trawls occur, but are limited with respect to overlap with the range of 
walrus and walrus feeding habitat. We did not identify any direct 
competition for prey resources between walruses and fisheries. In 
addition, as fisheries currently do not occur in the Chukchi Sea, they 
are not considered a serious threat to walrus at this time. We 
recognize the potential future interest by the fishing industry to 
initiate fisheries further north as fish distribution changes in 
association with predicted changes in ocean conditions. However, based 
on the limited fishing-related impacts to walrus that have occurred in 
other areas to date, and the active engagement of the NPFMC through the 
Arctic Fisheries Management Plan, we conclude that commercial fishing 
is not now a threat to Pacific walrus and is not likely to become a 
threat in the foreseeable future.
Shipping
    Commercial shipping and marine transportation vessels include oil 
and gas tankers, container ships, cargo ships, cruise ships, research 
vessels, icebreakers, and commercial fishing vessels. These vessels may 
travel to or from destinations within the Arctic (destination traffic), 
or may use the Arctic as a passageway between the Atlantic and Pacific 
Oceans (nondestination traffic). While the level of shipping activity 
is currently limited, the potential exists for increased activity in 
the future if changes in sea-ice patterns open new shipping lanes and 
result in a longer navigable season. Whether, and to what extent, 
marine transportation levels may change in the Arctic depends on a 
number of factors, including the extent of sea-ice melt, global trade 
dynamics, infrastructure development, the safety of Arctic shipping 
lanes, the marine insurance industry, and ship technology. Given these 
uncertainties, forecasts of future shipping levels in the Arctic are 
highly speculative (Arctic Council 2009, p. 1).
    Two major shipping lanes in the Arctic intersect the range of 
Pacific walrus: The Northwest Passage, which runs parallel to the 
Alaskan Coast through the Bering Strait up through the Canadian Arctic 
Archipelago; and the Northern Sea Route, which refers to a segment of 
the Northeast Passage paralleling the Russian Coast through the Bering 
Strait and into the Bering Sea (Garlich-Miller et al. 2011, Section 
3.6.4.1 ``Scope and Scale of Shipping'').
    Shipping levels in the Northwest Passage and Northern Sea Route are 
highly dependent on the extent of sea-ice cover. Walrus occur along 
both of these routes where they pass through the Bering Sea, Bering 
Strait, and Chukchi Sea. Given the dependence of shipping activities on 
the absence of sea ice, shipping levels are seasonally variable. Almost 
all activity occurs in June through September, and to a lesser extent, 
October and November, and April and May. Most walrus are in the Chukchi 
Sea during the height of the shipping season, although at times they 
are associated with sea ice or terrestrial haulouts. There is currently 
no commercial shipping or marine transportation in December through 
March (Arctic Council 2009, p. 85).
    Based on predicted sea-ice loss (Douglas 2010, p. 12), the 
navigation period in the Northern Sea Route is forecast to increase 
from 20-30 days to 90-100 days per year by 2100. Other factors that may 
lead to increased vessel traffic in the Arctic, in addition to reduced 
sea ice, include increased oil

[[Page 7670]]

and gas development, Arctic community population growth and associated 
development, and increased tourism (Brigham and Ellis 2004, pp. 8-9; 
Arctic Council 2009, p. 5).
    No quantitative analyses of changes in shipping levels currently 
exist. Both the Arctic Marine Shipping Assessment (AMSA) and the Arctic 
Marine Transport Workshop note that the greatest potential for 
increased shipping and marine transportation is the potential use of 
the Arctic as an alternative trade route connecting the Atlantic and 
Pacific Oceans. The Northwest Passage is not considered a viable Arctic 
throughway, given that the oldest and thickest sea ice in the Arctic is 
pushed into the western edge of the Canadian Arctic Archipelago, making 
the passage dangerous to navigate (Arctic Council 2009, p. 93). 
However, the passage was open in 2007 and 2010, due to ice-free 
conditions.
    The broad range of future shipping scenarios described in the AMSA 
and the Arctic Marine Transport Workshop underscore the uncertainties 
regarding future shipping levels. The AMSA notes that while the 
reduction in sea ice will provide the opportunity for increased 
shipping levels, ultimately it is economic factors, such as the 
feasibility of utilizing the Northern Sea Route as an alternative 
connection between the Atlantic and Pacific Oceans, that will determine 
future shipping levels (Arctic Council 2009, pp. 120-121).
    Increased shipping in the Bering and Chukchi Seas has the potential 
to impact Pacific walrus during the spring, summer, and fall seasons. 
An increase in shipping will result in increased potential for 
disturbance in the water and at terrestrial haulouts. According to 
Garlich-Miller et al. (2011, Section 3.2.1.2.3 ``Summer/Fall''), recent 
trends suggest that most of the Pacific walrus population will be 
foraging in open water from coastal haulouts along the Chukotka coast 
during the shipping season. Because the Northern Sea Route passes 
through this area, it is reasonable to expect walruses may be 
encountered along this route (Garlich-Miller et al. 2011, Figure 9). 
According to one study, however, walruses may be tolerant of ship 
activities, as 75 percent of walruses encountered by vessels in the 
Chukchi Sea exhibited no reaction to ship activities within 1 km (0.6 
mi) or less (Brueggeman et al. 1991, p. 139). This is confirmed by 
another study, which noted that walruses in water have been observed to 
generally show little concern about potential disturbance from 
approaching vessels, unless the ship came in very close proximity to 
them, in which case they dove or swam off to the side (Fay et al. 1984, 
p. 118). Therefore, we expect disturbance to walruses from shipping to 
be minimal. In situations where negligible impacts to a small number of 
walrus are anticipated from repeated displacement from a preferred 
feeding area, for example, or noise disturbance at haulouts, incidental 
take regulations could potentially be developed for U.S. vessels to 
permit take caused by shipping activities, which are subject to the 
MMPA. These activities likely would require mandatory monitoring and 
mitigation measures designed to minimize effects to walrus through 
vessel-based observers to avoid collisions and disturbance.
    As a result, shipping is not currently a threat to the Pacific 
walrus population, because shipping occurs at low levels, and shipping 
in support of other activities (e.g., oil and gas exploration) is 
sufficiently regulated and mitigated by MMPA incidental take 
regulations. Shipping may increase in the future, but shipping lanes 
are typically limited to narrow corridors, and disturbance from such 
activities is expected to be low. Moreover, given the uncertainties 
identified related to potential future shipping activities, we conclude 
that increased shipping activities are unlikely to cause population-
level effects to the Pacific walrus in the foreseeable future. In 
addition, take provisions of the MMPA can be effective in regulating 
shipping that may disturb haulouts and interrupt foraging activity in 
U.S. waters.
Oil Spills
    To date, there have been relatively few oil spills caused by marine 
vessel travel in the Bering and Chukchi seas. Within the seasonal range 
of walrus, there were approximately six vessel oil spill incidents 
between 1995 and 2004: two caused by fires, two by machinery damage or 
failure, one by grounding, and one by damage to the vessel. These 
incidents were small in scale and did not cause widespread impacts to 
walrus or their habitat. In general, the pattern of past vessel 
incidents corresponds to areas of high vessel traffic. Given 
anticipated increases in marine vessel travel within the range of 
Pacific walrus due to sea-ice decline, it is likely that the number of 
vessel incidents will increase in the foreseeable future.
    Oil spill response for walruses, and for wildlife in general, can 
be broken into three phases (Alaska Regional Response Team 2002, p. 
G1). Phase One is focused on eliminating the source of the spill, 
containing the spilled oil, and protecting environmentally sensitive 
areas. Phase Two involves efforts to herd or haze potentially affected 
wildlife away from the spill area. Phase Three, the most involved and 
most infrequently undertaken phase of oil spill response for wildlife, 
includes the capture and rehabilitation of oiled individuals.
    Even under the most stringent control systems, some tanker spills, 
pipeline leaks, and other accidents are likely to occur from equipment 
leaks or human error (O'Rourke 2010, p. 16). The history of oil spills 
and response in the Aleutian Islands raises concerns for potential 
spills in the Arctic region: ``The past 20 years of data on response to 
spills in the Aleutians has also shown that almost no oil has been 
recovered during events where attempts have been made by the 
responsible parties or government agencies, and that in many cases, 
weather and other conditions have prevented any response at all'' 
(O'Rourke 2010, p. 23). Moreover, the Commander of the Coast Guard's 
17th District, which covers Alaska, noted in an online journal that `` 
* * * we are not prepared for a major oil spill [over 100,000 gallons] 
in the Arctic environment. The Coast Guard currently has no offshore 
response capability in northern or western Alaska and we only dimly 
understand the science of recovering oil in broken ice'' (O'Rourke 
2010, p. 23). The behavior of oil spills in cold and icy waters is not 
well understood (O'Rourke 2010, p. 23). Cleaning up oil spills in ice-
covered waters will be more difficult than in other areas, primarily 
because effective strategies have yet to be developed.
    The Arctic conditions present several hurdles to oil cleanup 
efforts. In colder water temperatures, there are fewer organisms to 
break down the oil through microbial degradation and oil evaporates at 
a slower rate. Although slower evaporation may allow for more oil to be 
recovered, evaporation removes the lighter, more toxic hydrocarbons 
that are present in crude oil (O'Rourke 2010, p. 24). The longer the 
oil remains in an ecosystem, the more opportunity there is for 
exposure. Oil spills may get trapped in ice, evaporating only when the 
ice thaws, and in some cases, oil could remain in the ice for years. 
Icy conditions enhance emulsification--the process of forming different 
states of water in oil, often described as ``mousse.'' Emulsification 
creates oil cleanup challenges by increasing the volume of the oil/
water mixture and the mixture's viscosity (resistance to flow). The 
latter change creates particular problems for conventional removal and 
pumping cleanup methods (O'Rourke 2010, p. 24). Moreover, two of the 
major nonmechanical recovery methods--in-

[[Page 7671]]

situ burning and dispersant application--may be limited by the Arctic 
conditions and lack of logistical support such as aircraft, vessels, 
and other infrastructure (O'Rourke 2010, p. 24).
    As stated earlier, vessel-related spills were, and will likely 
continue to be, small in scale with localized impact to walrus and 
their habitat. A large-scale spill could have a major impact on the 
Pacific walrus population, depending on the spill and location relative 
to coastal aggregations. However, at present the chance of a large oil 
spill occurring in the Pacific walrus' range in the foreseeable future 
is considered low. Because most oil spills will have only localized 
impact to walrus, and the chance of a large-scale spill occurring in 
the walrus' range in the foreseeable future is low, oil spills do not 
appear to be a threat to Pacific walrus now or in the foreseeable 
future.
Icebreaking Activities
    Icebreaking activities can create noise that causes marine mammals 
to avoid areas where these activities are occurring. Further, 
icebreaking activities may increase the risk of oil spills by 
increasing vessel traffic in ice-filled waters. Given that marine 
mammals, including walrus, have been found to concentrate in and around 
temporary breaks in the ice created by icebreakers, there may be 
greater environmental impact associated with an oil spill involving an 
icebreaker or a vessel operating in a channel cleared by an icebreaker.
    Currently, Russian and Canadian icebreakers are used along the 
Northern Sea Route and within the Canadian Arctic Archipelago to clear 
passageways utilized by commercial shipping vessels (Arctic Council 
2009, p. 74), primarily in the summer months. The United States does 
not currently engage in icebreaking activities for navigational 
purposes in the Arctic (NRC 2005, p. 16). There are no current U.S. or 
State of Alaska regulations on icebreaking activities, mainly because 
icebreaking along the Alaskan Coast is minimal and usually carried out 
by the Coast Guard. However, in the last few years, oil and gas 
exploration activities in the Beaufort and Chukchi Seas have used 
privately contracted icebreakers in support of their operations.
    Icebreaking activities may increase in the future, given increases 
in commercial shipping and marine transportation. In particular, the 
establishment of the Northern Sea Route as a viable alternative trade 
route connecting the Atlantic and Pacific Oceans is contingent on, 
among other factors, the availability of a reliable government or 
private icebreaking fleet to clear the entire Route and provide 
predictable open shipping lanes (Arctic Marine Transport Workshop 2004, 
p. 1; Arctic Council 2009, p. 20). Although there are no current 
regulations on icebreaking activities in the Arctic, voluntary 
guidelines addressing icebreaking activities could be included as part 
of unified, multilateral regulation on Arctic shipping. According to 
the U.S. Department of Transportation, the International Maritime 
Organization (IMO) is considering developing icebreaking guidelines.
    Icebreaking is currently not a threat to the Pacific walrus 
population, because of the limited amount of icebreaking activity, 
current regulations associated with shipping in support of other 
activities (e.g., oil and gas development), and the relatively narrow 
corridors in which the activities occur. Shipping activity and 
associated icebreaking are predicted to increase in the future, but the 
magnitude and rate of increase are unknown and dependent on both 
economic and environmental factors. Given the uncertainties identified 
related to potential future shipping activities, the available 
information does not enable us to conclude that these activities will 
cause population-level effects to the Pacific walrus in the foreseeable 
future.
    Both the Service and USGS BN models included oil and gas 
development, commercial fisheries, and shipping as stressors (Garlich-
Miller et al. 2011, Section 3.8.5 ``Other Natural or Human Factors''; 
Jay et al. 2010b, p. 37). The USGS model also included air traffic and 
shipping activities simultaneously (Jay et al. 2010b, p. 37). In both 
models, these stressors had little influence on model outcomes 
(Garlich-Miller et al. 2011 Section 3.8.5 ``Other Natural or Human 
Factors''; Jay et al. 2010b, pp. 85-86, respectively).
Summary of Factor E
    Based on our estimation of low current contaminant loads and the 
likelihood of minimal future exposure as walruses feed on lower trophic 
levels, we conclude that contaminants are not a threat now and are not 
likely to be a threat to the Pacific walrus population in the 
foreseeable future. Oil and gas exploration, development, and 
production are currently not a threat to the Pacific walrus and are not 
expected to be in the foreseeable future, due to the anticipated 
increased scrutiny oil and gas development will undergo in the future, 
the continued application of incidental take regulations, and the low 
risk of an oil spill. Commercial fishing is also currently not a threat 
to walrus, as it occurs only on the periphery of the walrus' range and 
results in minimal impacts on the population. We recognize the 
potential future interest by the fishing industry to initiate fisheries 
further north as fish distribution changes in association with 
predicted changes in ocean conditions. However, based on the limited 
fishing-related impacts to walrus that have occurred in other areas to 
date, and the active engagement of the NPFMC through the Arctic 
Fisheries Management Plan, we conclude that commercial fishing is not 
now, and is not likely to become, a threat to Pacific walrus in the 
foreseeable future. Shipping is not currently a threat to the Pacific 
walrus population, because it occurs at low levels, and shipping in 
support of other activities (e.g., oil and gas exploration) is 
sufficiently regulated and mitigated by MMPA incidental take 
regulations. Shipping may increase in the future, but shipping lanes 
are typically limited to narrow corridors, and disturbance from such 
activities is expected to be low. Moreover, given the uncertainties 
identified related to potential future shipping activities, we conclude 
that increased shipping activities are unlikely to cause population-
level effects to the Pacific walrus in the foreseeable future. In 
addition, take provisions of the MMPA can be effective in regulating 
shipping in U.S. waters that may disturb haulouts and interrupt 
foraging activity. Because most oil spills will have only localized 
impact to walrus, and the chance of a large-scale spill occurring in 
the walrus' range in the foreseeable future is considered low, oil 
spills do not appear to be a threat to Pacific walrus now or in the 
foreseeable future. Finally, shipping activity and associated 
icebreaking is predicted to increase in the future, but the magnitude 
and rate of increase are unknown and dependent on both economic and 
environmental factors. Based on the best information available at this 
time, we are unable to conclude that these shipping activities will be 
a threat to the Pacific walrus in the foreseeable future, in light of 
the uncertainties in projecting the magnitude and rate of increase of 
these activities in the future.
    Therefore, based on our review of the best commercial and 
scientific data available, we conclude that none of the potential 
stressors identified and discussed under Factor E (``Other Natural or 
Manmade Factors Affecting Its Continued Existence of the Pacific 
Walrus'') is a threat to the Pacific walrus

[[Page 7672]]

now, or is likely to become a threat in the foreseeable future.

Finding

    As required by the Act, we considered each of the five factors 
under section 4(a)(1)(A) in assessing whether the Pacific walrus is 
endangered or threatened throughout all or a significant portion of its 
range. We carefully examined the best scientific and commercial 
information available regarding the past, present, and future threats 
faced by the Pacific walrus. We considered the information provided in 
the petition submitted to the Service by the Center for Biological 
Diversity; information available in our files; other available 
published and unpublished information; information submitted to the 
Service in response to our Federal Register notice of September 10, 
2009; and information submitted to the Service in response to our 
public news release requesting information on September 10, 2010. We 
also consulted with recognized Pacific walrus experts and other 
Federal, State, and Tribal agencies.
    In our analysis of Factor A, we identified and evaluated the risks 
of present or threatened destruction, modification, or curtailment of 
habitat or range of the Pacific walrus from (1) loss of sea ice due to 
climate change and (2) effects on prey species due to ocean warming and 
ocean acidification. We examined the likely responses and effects of 
changing sea-ice conditions in the Bering and Chukchi Seas on Pacific 
walruses. Pacific walrus is an ice-dependent species. Individuals use 
ice for many aspects of their life history throughout the year, and 
because of the projected loss of sea ice over the 21st century, we have 
identified the loss of sea ice and associated effects to be a threat to 
the Pacific walrus population. Although we anticipate that sufficient 
ice will remain, so that breeding behavior and calving will still occur 
in association with sea ice, the locations of these activities will 
likely change in response to changing ice patterns. The greatest change 
in sea ice, walrus distribution, and behavioral responses is expected 
to occur in the summer (June-August) and fall (October and November), 
when sea-ice loss is projected to be the greatest.
    Based on the best scientific information available, in the 
foreseeable future, we anticipate that there will be a 1-5-month period 
in which sea ice will typically retreat northward off of the Chukchi 
continental shelf. The Chukchi Sea is projected to be ice-free in 
September every year by mid-century. However, loss of sea ice is 
occurring faster than forecast and, on average, sea ice has retreated 
off the continental shelf for approximately 1 month per year during the 
last decade. At mid-century, model subsets project a 2-month ice-free 
season in the Chukchi Sea, and a 4-month ice-free season at the end of 
the century, centered on the month of September (Douglas 2010, p. 8), 
with some models indicating there will be 5 ice-free months. Based on 
the current rate of sea-ice loss, and the current rate of GHG 
increases, these changes may occur earlier in the century than 
currently projected.
    Through our analysis, we have concluded that loss of sea ice, with 
its concomitant changes to walrus distribution and life-history 
patterns, will lead to a population decline, and is a threat to Pacific 
walrus in the foreseeable future. We base this conclusion on the fact 
that, over time, walruses will be forced to rely on terrestrial 
haulouts to an increasingly greater extent. Although coastal haulouts 
have been traditionally used more frequently by males than by females 
with calves, in the future both sexes and all ages will be restricted 
to coastal habitats for a much greater period of time. This will expose 
all individuals, but especially calves, juveniles, and females, to 
increased levels of stress from depletion of prey, increased energetic 
costs to obtain prey, trampling injuries and mortalities, and 
predation. Although some of these stressors are currently acting on the 
population, we anticipate that their magnitude will increase over time 
as sea-ice loss over the continental shelf occurs regularly and more 
extensively. Given this persistent and increasing threat of sea-ice 
loss, we conclude that this anticipated Pacific walrus population 
decline will continue into the foreseeable future.
    Under Factor A, we also analyzed the effects of ocean warming and 
ocean acidification on Pacific walrus. Although we are concerned about 
the changes to the walrus prey base that may occur from ocean 
acidification and warming, and theoretically we understand how those 
stressors might operate, ocean dynamics are very complex and the 
specific outcomes for these stressors are too unreliable at this time 
for us to conclude that they are a threat to Pacific walrus now or in 
the foreseeable future. We therefore conclude that these stressors do 
not rise to the level of a threat, now or in the foreseeable future.
    In our analysis of Factor B, we identified and evaluated the risks 
to Pacific walrus from overutilization for commercial, recreational, 
scientific, or educational purposes. Under Factor B, we considered four 
potential risks to the Pacific walrus from overutilization relating to 
(1) Recreation, scientific, or educational purposes; (2) United States 
import/export; (3) commercial harvest; and (4) subsistence harvest. We 
found that recreational, scientific, and educational utilization of 
walruses is currently at low levels and is not projected to be a threat 
in the foreseeable future. United States import/export is not 
considered to be a threat to Pacific walrus now or in the foreseeable 
future, because most specimens imported into or exported from the 
United States are fossilized bone and ivory shards, and any other 
walrus ivory can only be imported into or exported from the United 
States after it has been legally harvested and substantially altered to 
qualify as a Native handicraft. Commercial and sport hunting of Pacific 
walrus in the United States is prohibited under the MMPA. Russian 
legislation also prohibits sport hunting of Pacific walruses. 
Commercial hunting in Russia has not occurred since 1991, and 
resumption would require the issuance of a governmental decree. In 
addition, any future commercial harvest in Russia must be based on a 
sustainable quota; therefore, it is unlikely that any potential future 
Russian commercial harvest will become a threat to the Pacific walrus 
population.
    With regard to the subsistence harvest of walrus, subsistence 
harvest in Chukotka, Russia, is controlled through a quota system. An 
annual subsistence quota is issued through a decree by the Russian 
Federal Fisheries Agency. Quota recommendations are based on what is 
thought to be a sustainable removal level (approximately 4 percent of 
the population), based on the total population and productivity 
estimates. However, there are no U.S. quotas on subsistence harvest. 
Although at present it is difficult to quantify sustainable removal 
levels because of the lack of information on Pacific walrus population 
status and trends, we determined that 4 percent is a conservative 
sustainable harvest level. The current level of subsistence harvest 
rangewide is about 4 percent of the 2006 population estimate. 
Therefore, we do not consider the current level of subsistence harvest 
to be a threat to Pacific walrus at the present time.
    Pacific walrus are an important subsistence resource in the Bering 
Strait region, and we expect Pacific walrus to continue to remain 
available for harvest there, even as sea-ice conditions change. Because 
there are no U.S. subsistence harvest quotas, we do not expect harvest

[[Page 7673]]

levels in the Bering Strait region to change appreciably in the 
foreseeable future, unless regulations are put in place to restrict 
harvest by limiting the number of walrus that may be taken. There are 
two paths that could result in harvest quotas: (1) Self-regulation 
activities by Alaska Natives; and (2) implementation of procedures in 
the MMPA. Neither of these is currently in place, except for one quota 
on Round Island, as discussed below. Instead, we predict that 
subsistence harvest is likely to continue at similar levels to those 
currently, even as the walrus population declines in response to loss 
of summer sea ice. Over time, as the proportion of animals harvested 
increases relative to the overall population, this continued level of 
subsistence harvest likely will become unsustainable. Therefore, we 
determine that subsistence harvest is a threat to the walrus population 
in the foreseeable future.
    In our analysis of Factor C, we identified and evaluated the risks 
to Pacific walrus from disease and predation, and we determined that 
neither component currently, or in the foreseeable future, represents 
threats to the Pacific walrus population. Although a changing climate 
may increase exposure of walrus to new pathogens, there are no clear 
transmission vectors that would change levels of exposure, and no 
evidence exists that disease will become a threat in foreseeable 
future.
    As the use of coastal haulouts by both walruses and polar bears 
during summer increases, we expect interactions between the two species 
to also increase, and terrestrial walrus haulouts may become important 
feeding areas for polar bears. The presence of polar bears along the 
coast during the ice-free season will likely influence patterns of 
haulout use as walrus shift to other coastal haulout locations. These 
movements may result in increased energetic costs to walrus, but it is 
not possible to predict the magnitude of these costs. Although 
predation by polar bears on Pacific walrus has been observed, the lack 
of documented population-level effects leads us to conclude that polar 
bear predation is not currently a threat to the Pacific walrus. As sea 
ice declines and Pacific walrus spend more time on coastal haulouts, 
however, it is likely that polar bear predation will increase. However, 
we cannot reliably predict the level of predation in the future, and 
therefore we are not able to conclude with sufficient reliability that 
it will rise to the level of a threat to the Pacific walrus population 
in the foreseeable future. There is no evidence that killer whale 
predation has ever limited the Pacific walrus population, and there is 
no evidence of increased presence of killer whales in the Bering or 
Chukchi Seas; therefore, killer whale predation is not a threat to the 
Pacific walrus now, and it is unlikely to become a threat in the 
foreseeable future.
    In our analysis under Factor D, we identified and evaluated the 
risks from the inadequacy of existing regulatory mechanisms by focusing 
our analysis on the specific laws and regulations aimed at addressing 
the two primary threats to the walrus--the loss of sea-ice habitat and 
subsistence harvest. As discussed previously under Factor A, GHG 
emissions have contributed to a warming climate and the loss of sea-ice 
habitat for the Pacific walrus. There are currently no regulatory 
mechanisms in place to reduce or limit GHG emissions. This situation 
was considered as part of our analysis in Factor A. Accordingly, there 
are no existing regulatory mechanisms to effectively address sea-ice 
loss.
    With regard to the other main threat to the walrus, subsistence 
harvest, there is currently no limit on the number of walrus that may 
be taken for subsistence purposes rangewide. While the subsistence 
harvest in Russia is controlled through a quota system, no national or 
Statewide quota exists in the United States. One local quota restricts 
the number of walrus that may be taken on Round Island (Alaska), but 
the harvest level in this area represents only a very minor portion of 
the harvest rangewide. Local ordinances recently adopted by two Native 
communities in the Bering Strait region, where 84 percent of the 
harvest in the United States and 43 percent of the rangewide harvest 
occurs, contain provisions aimed at restricting the number of hunting 
trips that may be taken for subsistence purposes. While these 
ordinances provide an important framework for future co-management 
initiatives and the potential development of future localized harvest 
limits, we acknowledge that no limits currently exist on the total 
number of walrus that may be taken in the Bering Strait region or 
rangewide. Nor are there other restrictions in place to ensure the 
likelihood that, as the population of walrus declines in response to 
changing sea-ice conditions, the subsistence harvest of walrus will 
occur at a reduced level. As a result, we determine that the existing 
regulatory mechanisms are inadequate to address the threat of 
subsistence harvest to the Pacific walrus in the foreseeable future.
    In our analysis under Factor E, we evaluated other factors that may 
have an effect on the Pacific walrus, including pollution and 
contaminants; oil and gas exploration, development, and production; 
commercial fisheries interactions; shipping; oil spills; and 
icebreaking activities. Based on our estimation of low current 
contaminant loads and the likelihood of minimal future exposure as 
walruses feed on lower trophic levels, we conclude that contaminants 
are not a threat now and are not likely to be a threat to the Pacific 
walrus population in the foreseeable future. Oil and gas development is 
currently not a threat to the Pacific walrus and is not expected to be 
in the foreseeable future due to the anticipated increased scrutiny oil 
and gas development will undergo in the future, the continued 
application of incidental take regulations, and the low risk of an oil 
spill. Commercial fishing is also currently not a threat to walrus as 
it occurs only on the periphery of the species' range and results in 
minimal impacts on the population. We recognize the potential future 
interest by the fishing industry to initiate fisheries further north as 
fish distribution changes in association with predicted changes in 
ocean conditions. However, based on the limited fishing-related impacts 
to walrus that have occurred in other areas to date, and the active 
engagement of the NPFMC through the Arctic Fisheries Management Plan, 
we conclude that commercial fishing is not now a threat to Pacific 
walrus, and is not likely to become a threat in the foreseeable future. 
Shipping is not currently a threat to the Pacific walrus population, 
because it occurs at low levels, and shipping in support of other 
activities (e.g., oil and gas exploration) is sufficiently regulated 
and mitigated by MMPA incidental take regulations. Shipping may 
increase in the future, but given the uncertainties identified related 
to potential future shipping activities, the available information does 
not allow us to conclude that these activities will cause population-
level effects to the Pacific walrus in the foreseeable future. In 
addition, take provisions of the MMPA can be effective in regulating 
shipping in U.S. waters that may disturb haulouts and interrupt 
foraging activity. Because most oil spills will have only localized 
impact to walrus, and the chance of a large-scale spill occurring in 
the walrus' range in the foreseeable future is considered low, oil 
spills do not appear to be a threat to Pacific walrus now or in the 
foreseeable future. Finally, shipping activity and associated 
icebreaking are predicted to increase in the future, but the magnitude 
and rate of increase are unknown and dependent on both

[[Page 7674]]

economic and environmental factors. Given the uncertainties identified 
related to potential future shipping activities, the available 
information does not enable us to conclude that icebreaking will cause 
population-level effects to the Pacific walrus in the foreseeable 
future. Therefore, we determine that none of the potential stressors 
identified and discussed under Factor E is a threat to the Pacific 
walrus now, or is likely to become a threat in the foreseeable future.
    In summary, we identify loss of sea ice in the summer and fall and 
associated impacts (Factor A) and subsistence harvest (Factor B) as the 
primary threats to the Pacific walrus in the foreseeable future. These 
conclusions are supported by the Bayesian Network models prepared by 
USGS and the Service. Our Factor D analysis determined that existing 
regulatory mechanisms are currently inadequate to address these 
threats. These threats are of sufficient imminence, intensity, and 
magnitude to cause substantial losses of abundance and an anticipated 
population decline of Pacific walrus that will continue into the 
foreseeable future.
    Therefore, on the basis of the best scientific and commercial 
information available, we find that the petitioned action to list the 
Pacific walrus is warranted. We will make a determination on the status 
of the species as threatened or endangered when we prepare a proposed 
listing determination. However, as explained in more detail below, an 
immediate proposal of a regulation implementing this action is 
precluded by higher priority listing actions, and expeditious progress 
is being made to add or remove qualified species from the Lists of 
Endangered and Threatened Wildlife and Plants.
    We reviewed the available information to determine if the existing 
and foreseeable threats render the species at risk of extinction at 
this time such that issuing an emergency regulation temporarily listing 
the species under section 4(b)(7) of the Act is warranted. We 
determined that issuing an emergency regulation temporarily listing the 
species is not warranted for this species at this time, because the 
threats acting on the species are not immediately impacting the entire 
species across its range to the point where the species will be 
immediately lost. However, if at any time we determine that issuing an 
emergency regulation temporarily listing the Pacific walrus is 
warranted, we will initiate this action at that time.

Listing Priority Number

    The Service adopted guidelines on September 21, 1983 (48 FR 43098), 
to establish a rational system for utilizing available resources for 
the highest priority species when adding species to the Lists of 
Endangered and Threatened Wildlife and Plants or reclassifying species 
listed as threatened to endangered status. These guidelines, titled 
``Endangered and Threatened Species Listing and Recovery Priority 
Guidelines,'' address the immediacy and magnitude of threats, and the 
level of taxonomic distinctiveness. The system places greatest 
importance on the immediacy and magnitude of threats, but also factors 
in the level of taxonomic distinctiveness by assigning priority in 
descending order to monotypic genera (genus with one species), full 
species, and subspecies (or equivalently, distinct population segments 
of vertebrates).
    As a result of our analysis of the best available scientific and 
commercial information, we assigned the Pacific walrus a Listing 
Priority Number (LPN) of 9, based on the moderate magnitude and 
imminence of threats. These threats include the present or threatened 
destruction, modification or curtailment of Pacific walrus habitat due 
to loss of sea-ice habitat; and overutilization due to subsistence 
harvest. In addition, existing regulatory mechanisms fail to address 
these threats. These threats affect the entire population, are ongoing, 
and will continue to occur into the foreseeable future. Our rationale 
for assigning the Pacific walrus an LPN of 9 is outlined below.
    Under the Service's Guidelines, the magnitude of threat is the 
first criterion we look at when establishing a listing priority. The 
guidelines indicate that species with the highest magnitude of threat 
are those species facing the most severe threats to their continued 
existence. These species receive the highest listing priority. As 
discussed in the finding, the Pacific walrus is being impacted by two 
primary threats; the loss of sea-ice habitat, and subsistence harvest. 
The main threat to the Pacific walrus is the loss of sea-ice habitat 
due to climate change. Sea-ice losses have been observed to date and 
are projected to continue through the end of the 21st century. The loss 
of sea-ice habitat, while affecting individual walrus or localized 
populations, does not appear to be currently resulting in significant 
population-level effects. However, the modeled projections of the loss 
of sea-ice habitat and the associated impacts on the Pacific walrus are 
expected to greatly increase within the foreseeable future, thereby 
resulting in significant population-level effects. Because the threat 
of the loss of sea-ice habitat is not having significant effects 
currently, but is projected to, we have determined the magnitude of 
this threat is moderate, and not high.
    Subsistence harvest is also identified as a threat to the Pacific 
walrus. Harvest is currently occurring at sustainable levels. With the 
loss of sea-ice habitat and the projected associated population 
decline, and because subsistence harvest is expected to continue at 
current levels, we concluded that subsistence harvest would have a 
population-level effect on the species in the future. Because harvest 
is occurring at sustainable levels now, but may become unsustainable in 
the foreseeable future due to the projected population decline, we have 
determined the magnitude of the threat of subsistence harvest is 
considered to be moderate, and not high.
    Under our Guidelines, the second criterion we consider in assigning 
a listing priority is the immediacy of threats. This criterion is 
intended to ensure that species that face actual, identifiable threats 
are given priority over those species for which threats are only 
potential or species that are intrinsically vulnerable but are not 
known to be presently facing such threats. We have determined that loss 
of sea-ice habitat is affecting the Pacific walrus population currently 
and is expected to continue and likely intensify in the foreseeable 
future. Similarly, we have determined that subsistence harvest is 
presently occurring and expected to continue at current levels into the 
foreseeable future, even as the Pacific walrus population declines due 
to sea-ice loss. Because both the loss of sea-ice habitat and 
subsistence harvest are presently occurring, we consider the threats to 
be imminent.
    The third criterion in our guidelines is intended to devote 
resources to those species representing highly distinctive or isolated 
gene pools as reflected by taxonomy, with the highest priority given to 
monotypic genera, followed by species and then subspecies. The Pacific 
walrus is a valid subspecies and therefore receives a lower priority 
than species or a monotypic genus. As discussed, the threats affecting 
the Pacific walrus are of moderate magnitude and imminent. Accordingly 
we have assigned the Pacific walrus an LPN of 9, pursuant to our 
guidelines.
    We will continue to monitor the threats to the Pacific walrus, as 
well as the species' status, on an annual basis, and should the 
magnitude or the

[[Page 7675]]

imminence of the threats change, we will revisit our assessment of the 
LPN.

Preclusion and Expeditious Progress

    Preclusion is a function of the listing priority of a species in 
relation to the resources that are available and the cost and relative 
priority of competing demands for those resources. Thus, in any given 
fiscal year (FY), multiple factors dictate whether it will be possible 
to undertake work on a listing proposal regulation or whether 
promulgation of such a proposal is precluded by higher-priority listing 
actions.
    The resources available for listing actions are determined through 
the annual Congressional appropriations process. The appropriation for 
the Listing Program is available to support work involving the 
following listing actions: Proposed and final listing rules; 90-day and 
12-month findings on petitions to add species to the Lists of 
Endangered and Threatened Wildlife and Plants (Lists) or to change the 
status of a species from threatened to endangered; annual 
``resubmitted'' petition findings on prior warranted-but-precluded 
petition findings as required under section 4(b)(3)(C)(i) of the Act; 
critical habitat petition findings; proposed and final rules 
designating critical habitat; and litigation-related, administrative, 
and program-management functions (including preparing and allocating 
budgets, responding to Congressional and public inquiries, and 
conducting public outreach regarding listing and critical habitat). The 
work involved in preparing various listing documents can be extensive 
and may include, but is not limited to: Gathering and assessing the 
best scientific and commercial data available and conducting analyses 
used as the basis for our decisions; writing and publishing documents; 
and obtaining, reviewing, and evaluating public comments and peer 
review comments on proposed rules and incorporating relevant 
information into final rules. The number of listing actions that we can 
undertake in a given year also is influenced by the complexity of those 
listing actions; that is, more complex actions generally are more 
costly. The median cost for preparing and publishing a 90-day finding 
is $39,276; for a 12-month finding, $100,690; for a proposed rule with 
critical habitat, $345,000; and for a final listing rule with critical 
habitat, the median cost is $305,000.
    We cannot spend more than is appropriated for the Listing Program 
without violating the Anti-Deficiency Act (see 31 U.S.C. 
1341(a)(1)(A)). In addition, in FY 1998 and for each fiscal year since 
then, Congress has placed a statutory cap on funds which may be 
expended for the Listing Program, equal to the amount expressly 
appropriated for that purpose in that fiscal year. This cap was 
designed to prevent funds appropriated for other functions under the 
Act (for example, recovery funds for removing species from the Lists), 
or for other Service programs, from being used for Listing Program 
actions (see House Report 105-163, 105th Congress, 1st Session, July 1, 
1997).
    Since FY 2002, the Service's budget has included a critical habitat 
subcap to ensure that some funds are available for other work in the 
Listing Program (``The critical habitat designation subcap will ensure 
that some funding is available to address other listing activities'' 
(House Report No. 107-103, 107th Congress, 1st Session, June 19, 
2001)). From FY 2002 to FY 2006, the Service has had to use virtually 
the entire critical habitat subcap to address court-mandated 
designations of critical habitat, and consequently none of the critical 
habitat subcap funds have been available for other listing activities. 
In some FYs since 2006, we have been able to use some of the critical 
habitat subcap funds for proposed listing determinations for high-
priority candidate species. In other FYs, while we were unable to use 
any of the critical habitat subcap funds to fund proposed listing 
determinations, we did use some of this money to fund the critical 
habitat portion of some proposed listing determinations so that the 
proposed listing determination and proposed critical habitat 
designation could be combined into one rule, thereby being more 
efficient in our work. At this time, for FY 2011, we do not know if we 
will be able to use some of the critical habitat subcap funds to fund 
proposed listing determinations.
    We make our determinations of preclusion on a nationwide basis to 
ensure that the species most in need of listing will be addressed first 
and also because we allocate our listing budget on a nationwide basis. 
Through the listing cap, the critical habitat subcap, and the amount of 
funds needed to address court-mandated critical habitat designations, 
Congress and the courts have, in effect, determined the amount of money 
available for other listing activities nationwide (i.e., actions other 
than critical habitat designation). Therefore, the funds in the listing 
cap, other than those needed to address court-mandated critical habitat 
for already listed species, set the limits on our determinations of 
preclusion and expeditious progress.
    Congress identified the availability of resources as the only basis 
for deferring the initiation of a rulemaking that is warranted. The 
Conference Report accompanying Pub. L. 97-304 (Endangered Species Act 
Amendments of 1982), which established the current statutory deadlines 
and the warranted-but-precluded finding, states that the amendments 
were ``not intended to allow the Secretary to delay commencing the 
rulemaking process for any reason other than that the existence of 
pending or imminent proposals to list species subject to a greater 
degree of threat would make allocation of resources to such a petition 
[that is, for a lower-ranking species] unwise.'' Although that 
statement appeared to refer specifically to the ``to the maximum extent 
practicable'' limitation on the 90-day deadline for making a 
``substantial information'' finding, that finding is made at the point 
when the Service is deciding whether or not to commence a status review 
that will determine the degree of threats facing the species, and 
therefore the analysis underlying the statement is more relevant to the 
use of the warranted-but-precluded finding, which is made when the 
Service has already determined the degree of threats facing the species 
and is deciding whether or not to commence a rulemaking.
    In FY 2011, on December 22, 2010, Congress passed a continuing 
resolution which provides funding at the FY 2010 enacted level through 
March 4, 2011. Until Congress appropriates funds for FY 2011 at a 
different level, we will fund listing work based on the FY 2010 amount. 
Thus, at this time in FY 2011, the Service anticipates an appropriation 
of $22,103,000 based on FY 2010 appropriations. Of that, the Service 
anticipates needing to dedicate $11,632,000 for determinations of 
critical habitat for already listed species. Also $500,000 is 
appropriated for foreign species listings under the Act. The Service 
thus has $9,971,000 available to fund work in the following categories: 
compliance with court orders and court-approved settlement agreements 
requiring that petition findings or listing determinations be completed 
by a specific date; section 4 (of the Act) listing actions with 
absolute statutory deadlines; essential litigation-related, 
administrative, and listing program-management functions; and high-
priority listing actions for some of our candidate species. In FY 2010 
the Service received many new petitions and a single petition to list 
404 species. The receipt of petitions for a large number of species is 
consuming the

[[Page 7676]]

Service's listing funding that is not dedicated to meeting Court-
ordered commitments. Absent some ability to balance effort among 
listing duties under existing funding levels, it is unlikely that the 
Service will be able to make expeditious progress on candidate species 
in FY 2011.
    In 2009, the responsibility for listing foreign species under the 
Act was transferred from the Division of Scientific Authority, 
International Affairs Program, to the Endangered Species Program. 
Therefore, starting in FY 2010, we used a portion of our funding to 
work on the actions described above for listing actions related to 
foreign species. In FY 2011, we anticipate using $1,500,000 for work on 
listing actions for foreign species which reduces funding available for 
domestic listing actions, however, currently only $500,000 has been 
allocated. Although there are currently no foreign species issues 
included in our high-priority listing actions at this time, many 
actions have statutory or court-approved settlement deadlines, thus 
increasing their priority. The budget allocations for each specific 
listing action are identified in the Service's FY 2011 Allocation Table 
(part of our record).
    For the above reasons, funding a proposed listing determination for 
the Pacific walrus is precluded by court-ordered and court-approved 
settlement agreements, listing actions with absolute statutory 
deadlines, and work on proposed listing determinations for those 
candidate species with a higher listing priority (i.e., candidate 
species with LPNs of 1-8).
    Based on our September 21, 1983, guidance for assigning an LPN for 
each candidate species (48 FR 43098), we have a significant number of 
species with an LPN of 2. Using this guidance, we assign each candidate 
an LPN of 1 to 12, depending on the magnitude of threats (high or 
moderate to low), immediacy of threats (imminent or nonimminent), and 
taxonomic status of the species (in order of priority: monotypic genus 
(a species that is the sole member of a genus); species, or part of a 
species (subspecies, distinct population segment, or significant 
portion of the range)). The lower the listing priority number, the 
higher the listing priority (that is, a species with an LPN of 1 would 
have the highest listing priority).
    Because of the large number of high-priority species, we have 
further ranked the candidate species with an LPN of 2 by using the 
following extinction-risk type criteria: International Union for the 
Conservation of Nature and Natural Resources (IUCN) Red list status/
rank, Heritage rank (provided by NatureServe), Heritage threat rank 
(provided by NatureServe), and species currently with fewer than 50 
individuals, or 4 or fewer populations. Those species with the highest 
IUCN rank (critically endangered), the highest Heritage rank (G1), the 
highest Heritage threat rank (substantial, imminent threats), and 
currently with fewer than 50 individuals, or fewer than 4 populations, 
originally comprised a group of approximately 40 candidate species 
(``Top 40''). These 40 candidate species have had the highest priority 
to receive funding to work on a proposed listing determination. As we 
work on proposed and final listing rules for those 40 candidates, we 
apply the ranking criteria to the next group of candidates with an LPN 
of 2 and 3 to determine the next set of highest-priority candidate 
species. Finally, proposed rules for reclassification of threatened 
species to endangered are lower priority, since as listed species, they 
are already afforded the protection of the Act and implementing 
regulations. However, for efficiency reasons, we may choose to work on 
a proposed rule to reclassify a species to endangered if we can combine 
this with work that is subject to a court-determined deadline.
    With our workload so much bigger than the amount of funds we have 
to accomplish it, it is important that we be as efficient as possible 
in our listing process. Therefore, as we work on proposed rules for the 
highest priority species in the next several years, we are preparing 
multi-species proposals when appropriate, and these may include species 
with lower priority if they overlap geographically or have the same 
threats as a species with an LPN of 2. In addition, we take into 
consideration the availability of staff resources when we determine 
which high-priority species will receive funding to minimize the amount 
of time and resources required to complete each listing action.
    As explained above, a determination that listing is warranted but 
precluded must also demonstrate that expeditious progress is being made 
to add and remove qualified species to and from the Lists of Endangered 
and Threatened Wildlife and Plants. As with our ``precluded'' finding, 
the evaluation of whether progress in adding qualified species to the 
Lists has been expeditious is a function of the resources available for 
listing and the competing demands for those funds. (Although we do not 
discuss it in detail here, we are also making expeditious progress in 
removing species from the list under the Recovery program in light of 
the resource available for delisting, which is funded by a separate 
line item in the budget of the Endangered Species Program. So far 
during FY 2011, we have completed one delisting rule.) Given the 
limited resources available for listing, we find that we are making 
expeditious progress in FY 2011 in the Listing program. This progress 
included preparing and publishing the following determinations:

                                        FY 2011 Completed Listing Actions
----------------------------------------------------------------------------------------------------------------
       Publication date                       Title                      Actions                 FR pages
----------------------------------------------------------------------------------------------------------------
10/6/2010.....................  Endangered Status for the         Proposed Listing             75 FR 61664-61690
                                 Altamaha Spinymussel and          Endangered.
                                 Designation of Critical Habitat.
10/7/2010.....................  12-month Finding on a Petition    Notice of 12-month           75 FR 62070-62095
                                 to list the Sacramento            petition finding,
                                 Splittail as Endangered or        Not warranted.
                                 Threatened.
10/28/2010....................  Endangered Status and             Proposed Listing             75 FR 66481-66552
                                 Designation of Critical Habitat   Endangered
                                 for Spikedace and Loach Minnow.   (uplisting).
11/2/2010.....................  90-Day Finding on a Petition to   Notice of 90-day             75 FR 67341-67343
                                 List the Bay Springs Salamander   Petition Finding,
                                 as Endangered.                    Not substantial.
11/2/2010.....................  Determination of Endangered       Final Listing                75 FR 67511-67550
                                 Status for the Georgia Pigtoe     Endangered.
                                 Mussel, Interrupted Rocksnail,
                                 and Rough Hornsnail and
                                 Designation of Critical Habitat.
11/2/2010.....................  Listing the Rayed Bean and        Proposed Listing             75 FR 67551-67583
                                 Snuffbox as Endangered.           Endangered.
11/4/2010.....................  12-Month Finding on a Petition    Notice of 12-month           75 FR 67925-67944
                                 to List Cirsium wrightii          petition finding,
                                 (Wright's Marsh Thistle) as       Warranted but
                                 Endangered or Threatened.         precluded.

[[Page 7677]]

 
12/14/2010....................  Endangered Status for Dunes       Proposed Listing             75 FR 77801-77817
                                 Sagebrush Lizard.                 Endangered.
12/14/2010....................  12-month Finding on a Petition    Notice of 12-month           75 FR 78029-78061
                                 to List the North American        petition finding,
                                 Wolverine as Endangered or        Warranted but
                                 Threatened.                       precluded.
12/14/2010....................  12-Month Finding on a Petition    Notice of 12-month           75 FR 78093-78146
                                 to List the Sonoran Population    petition finding,
                                 of the Desert Tortoise as         Warranted but
                                 Endangered or Threatened.         precluded.
12/15/2010....................  12-Month Finding on a Petition    Notice of 12-month           75 FR 78513-78556
                                 to List Astragalus microcymbus    petition finding,
                                 and Astragalus schmolliae as      Warranted but
                                 Endangered or Threatened.         precluded.
12/28/2010....................  Listing Seven Brazilian Bird      Final Listing                75 FR 81793-81815
                                 Species as Endangered             Endangered.
                                 Throughout Their Range.
1/4/2011......................  90[dash]Day Finding on a          Notice of 90-day                 76 FR 304-311
                                 Petition to List the Red Knot     Petition Finding,
                                 subspecies Calidris canutus       Not substantial.
                                 roselaari as Endangered.
1/19/2011.....................  Endangered Status for the         Proposed Listing               76 FR 3392-3420
                                 Sheepnose and Spectaclecase       Endangered.
                                 Mussels.
----------------------------------------------------------------------------------------------------------------

    Our expeditious progress also includes work on listing actions that 
we funded in FY 2010 and FY 2011, but have not yet been completed to 
date. These actions are listed below. Actions in the top section of the 
table are being conducted under a deadline set by a court. Actions in 
the middle section of the table are being conducted to meet statutory 
timelines, that is, timelines required under the Act. Actions in the 
bottom section of the table are high-priority listing actions. These 
actions include work primarily on species with an LPN of 2, and, as 
discussed above, selection of these species is partially based on 
available staff resources, and when appropriate, include species with a 
lower priority if they overlap geographically or have the same threats 
as the species with the high priority. Including these species together 
in the same proposed rule results in considerable savings in time and 
funding compared to preparing separate proposed rules for each of them 
in the future.

       Actions Funded in FY 2010 and FY 2011 but Not Yet Completed
------------------------------------------------------------------------
                  Species                               Action
------------------------------------------------------------------------
           Actions Subject to Court Order/Settlement Agreement
------------------------------------------------------------------------
Flat-tailed horned lizard..................  Final listing
                                              determination.
Mountain plover\4\.........................  Final listing
                                              determination.
Solanum conocarpum.........................  12-month petition finding.
Thorne's Hairstreak butterfly\3\...........  12-month petition finding.
Hermes copper butterfly\3\.................  12-month petition finding.
4 parrot species (military macaw, yellow-    12-month petition finding.
 billed parrot, red-crowned parrot, scarlet
 macaw)\5\.
4 parrot species (blue-headed macaw, great   12-month petition finding.
 green macaw, grey-cheeked parakeet,
 hyacinth macaw)\5\.
4 parrot species (crimson shining parrot,    12-month petition finding.
 white cockatoo, Philippine cockatoo,
 yellow-crested cockatoo)\5\.
Utah prairie dog (uplisting)...............  90-day petition finding.
------------------------------------------------------------------------
                    Actions With Statutory Deadlines
------------------------------------------------------------------------
Casey's june beetle........................  Final listing
                                              determination.
Southern rockhopper penguin--Campbell        Final listing
 Plateau population.                          determination.
6 Birds from Eurasia.......................  Final listing
                                              determination.
5 Bird species from Colombia and Ecuador...  Final listing
                                              determination.
Queen Charlotte goshawk....................  Final listing
                                              determination.
5 species southeast fish (Cumberland         Final listing
 darter, rush darter, yellowcheek darter,     determination.
 chucky madtom, and laurel dace)\4\.
Ozark hellbender\4\........................  Final listing
                                              determination.
Altamaha spinymussel\3\....................  Final listing
                                              determination.
3 Colorado plants (Ipomopsis polyantha       Final listing
 (Pagosa Skyrocket), Penstemon debilis        determination.
 (Parachute Beardtongue), and Phacelia
 submutica (DeBeque Phacelia))\4\.
Salmon crested cockatoo....................  Final listing
                                              determination.
6 Birds from Peru & Bolivia................  Final listing
                                              determination.
Loggerhead sea turtle (assist National       Final listing
 Marine Fisheries Service)\5\.                determination.
2 mussels (rayed bean (LPN = 2), snuffbox    Final listing
 No LPN)\5\.                                  determination.
Mt Charleston blue\5\......................  Proposed listing
                                              determination.
CA golden trout\4\.........................  12-month petition finding.
Black-footed albatross.....................  12-month petition finding.
Mount Charleston blue butterfly............  12-month petition finding.
Mojave fringe-toed lizard\1\...............  12-month petition finding.
Kokanee--Lake Sammamish population\1\......  12-month petition finding.
Cactus ferruginous pygmy-owl\1\............  12-month petition finding.
Northern leopard frog......................  12-month petition finding.
Tehachapi slender salamander...............  12-month petition finding.

[[Page 7678]]

 
Coqui Llanero..............................  12-month petition finding/
                                              Proposed listing.
Dusky tree vole............................  12-month petition finding.
3 MT invertebrates (mist forestfly (Lednia   12-month petition finding.
 tumana), Oreohelix sp. 3, Oreohelix sp.
 31) from 206 species petition.
5 UT plants (Astragalus hamiltonii,          12-month petition finding.
 Eriogonum soredium, Lepidium ostleri,
 Penstemon flowersii, Trifolium friscanum)
 from 206 species petition.
5 WY plants (Abronia ammophila, Agrostis     12-month petition finding.
 rossiae, Astragalus proimanthus, Boechere
 (Arabis) pusilla, Penstemon gibbensii)
 from 206 species petition.
Leatherside chub (from 206 species           12-month petition finding.
 petition).
Frigid ambersnail (from 206 species          12-month petition finding.
 petition)\3\.
Platte River caddisfly (from 206 species     12-month petition finding.
 petition)\5\.
Gopher tortoise--eastern population........  12-month petition finding.
Grand Canyon scorpion (from 475 species      12-month petition finding.
 petition).
Anacroneuria wipukupa (a stonefly from 475   12-month petition finding.
 species petition)\4\.
Rattlesnake-master borer moth (from 475      12-month petition finding.
 species petition)\3\.
3 Texas moths (Ursia furtiva, Sphingicampa   12-month petition finding.
 blanchardi, Agapema galbina) (from 475
 species petition).
2 Texas shiners (Cyprinella sp., Cyprinella  12-month petition finding.
 lepida) (from 475 species petition).
3 South Arizona plants (Erigeron             12-month petition finding.
 piscaticus, Astragalus hypoxylus,
 Amoreuxia gonzalezii) (from 475 species
 petition).
5 Central Texas mussel species (3 from 475   12-month petition finding.
 species petition).
14 parrots (foreign species)...............  12-month petition finding.
Berry Cave salamander\1\...................  12-month petition finding.
Striped Newt\1\............................  12-month petition finding.
Fisher--Northern Rocky Mountain Range\1\...  12-month petition finding.
Mohave Ground Squirrel\1\..................  12-month petition finding.
Puerto Rico Harlequin Butterfly\3\.........  12-month petition finding.
Western gull-billed tern...................  12-month petition finding.
Ozark chinquapin (Castanea pumila var.       12-month petition finding.
 ozarkensis)\4\.
HI yellow-faced bees.......................  12-month petition finding.
Giant Palouse earthworm....................  12-month petition finding.
Whitebark pine.............................  12-month petition finding.
OK grass pink (Calopogon oklahomensis)\1\..  12-month petition finding.
Ashy storm-petrel\5\.......................  12-month petition finding.
Honduran emerald...........................  12-month petition finding.
Southeastern pop snowy plover & wintering    90-day petition finding.
 pop. of piping plover\1\.
Eagle Lake trout\1\........................  90-day petition finding.
Smooth-billed ani\1\.......................  90-day petition finding.
32 Pacific Northwest mollusks species        90-day petition finding.
 (snails and slugs)\1\.
42 snail species (Nevada & Utah)...........  90-day petition finding.
Peary caribou..............................  90-day petition finding.
Plains bison...............................  90-day petition finding.
Spring Mountains checkerspot butterfly.....  90-day petition finding.
Spring pygmy sunfish.......................  90-day petition finding.
Bay skipper................................  90-day petition finding.
Unsilvered fritillary......................  90-day petition finding.
Texas kangaroo rat.........................  90-day petition finding.
Spot-tailed earless lizard.................  90-day petition finding.
Eastern small-footed bat...................  90-day petition finding.
Northern long-eared bat....................  90-day petition finding.
Prairie chub...............................  90-day petition finding.
10 species of Great Basin butterfly........  90-day petition finding.
6 sand dune (scarab) beetles...............  90-day petition finding.
Golden-winged warbler\4\...................  90-day petition finding.
Sand-verbena moth..........................  90-day petition finding.
404 Southeast species......................  90-day petition finding.
Franklin's bumble bee\4\...................  90-day petition finding.
2 Idaho snowflies (straight snowfly & Idaho  90-day petition finding.
 snowfly)\4\.
American eel\4\............................  90-day petition finding.
Gila monster (Utah population)\4\..........  90-day petition finding.
Arapahoe snowfly\4\........................  90-day petition finding.
Leona's little blue\4\.....................  90-day petition finding.
Aztec gilia\5\.............................  90-day petition finding.
White-tailed ptarmigan\5\..................  90-day petition finding.
San Bernardino flying squirrel\5\..........  90-day petition finding.
Bicknell's thrush\5\.......................  90-day petition finding.
Chimpanzee.................................  90-day petition finding.
Sonoran talussnail\5\......................  90-day petition finding.
2 AZ Sky Island plants (Graptopetalum        90-day petition finding.
 bartrami & Pectis imberbis)\5\.
I'iwi\5\...................................  90-day petition finding.
------------------------------------------------------------------------

[[Page 7679]]

 
                      High-Priority Listing Actions
------------------------------------------------------------------------
19 Oahu candidate species\2\ (16 plants, 3   Proposed listing.
 damselflies) (15 with LPN = 2, 3 with LPN
 = 3, 1 with LPN = 9).
19 Maui-Nui candidate species\2\ (16         Proposed listing.
 plants, 3 tree snails) (14 with LPN = 2, 2
 with LPN = 3, 3 with LPN = 8).
2 Arizona springsnails\2\ (Pyrgulopsis       Proposed listing.
 bernadina (LPN = 2), Pyrgulopsis trivialis
 (LPN = 2)).
Chupadera springsnail\2\ (Pyrgulopsis        Proposed listing.
 chupaderae (LPN = 2).
8 Gulf Coast mussels (southern kidneyshell   Proposed listing.
 (LPN = 2), round ebonyshell (LPN = 2),
 Alabama pearlshell (LPN = 2), southern
 sandshell (LPN = 5), fuzzy pigtoe (LPN =
 5), Choctaw bean (LPN = 5), narrow pigtoe
 (LPN = 5), and tapered pigtoe (LPN =
 11))\4\.
Umtanum buckwheat (LPN = 2) and white        Proposed listing.
 bluffs bladderpod (LPN = 9)\4\.
Grotto sculpin (LPN = 2)\4\................  Proposed listing.
2 Arkansas mussels (Neosho mucket (LPN = 2)  Proposed listing.
 & Rabbitsfoot (LPN = 9))\4\.
Diamond darter (LPN = 2)\4\................  Proposed listing.
Gunnison sage-grouse (LPN = 2)\4\..........  Proposed listing.
Miami blue (LPN = 3)\3\....................  Proposed listing.
4 Texas salamanders (Austin blind            Proposed listing.
 salamander (LPN = 2), Salado salamander
 (LPN = 2), Georgetown salamander (LPN =
 8), Jollyville Plateau (LPN = 8))\3\.
5 SW aquatics (Gonzales Spring Snail (LPN =  Proposed listing.
 2), Diamond Y springsnail (LPN = 2),
 Phantom springsnail (LPN = 2), Phantom
 Cave snail (LPN = 2), Diminutive amphipod
 (LPN = 2))\3\.
2 Texas plants (Texas golden gladecress      Proposed listing.
 (Leavenworthia texana) (LPN = 2), Neches
 River rose-mallow (Hibiscus dasycalyx)
 (LPN = 2))\3\.
FL bonneted bat (LPN = 2)\3\...............  Proposed listing.
21 Big Island (HI) species\5\ (includes 8    Proposed listing.
 candidate species--5 plants & 3 animals; 4
 with LPN = 2, 1 with LPN = 3, 1 with LPN =
 4, 2 with LPN = 8).
12 Puget Sound prairie species (9            Proposed listing.
 subspecies of pocket gopher (Thomomys
 mazama ssp.) (LPN = 3), streaked horned
 lark (LPN = 3), Taylor's checkerspot (LPN
 = 3), Mardon skipper (LPN = 8))\3\.
2 TN River mussels (fluted kidneyshell (LPN  Proposed listing.
 = 2), slabside pearlymussel (LPN = 2))\5\.
Jemez Mountain salamander (LPN = 2) \5\....  Proposed listing.
------------------------------------------------------------------------
\1\ Funds for listing actions for these species were provided in
  previous FYs.
\2\ Although funds for these high-priority listing actions were provided
  in FY 2008 or 2009, due to the complexity of these actions and
  competing priorities, these actions are still being developed.
\3\ Partially funded with FY 2010 funds and FY 2011 funds.
\4\ Funded with FY 2010 funds.
\5\ Funded with FY 2011 funds.

    We have endeavored to make our listing actions as efficient and 
timely as possible, given the requirements of the relevant law and 
regulations and constraints relating to workload and personnel. We are 
continually considering ways to streamline processes or achieve 
economies of scale, such as by batching related actions together. Given 
our limited budget for implementing section 4 of the Act, these actions 
described above collectively constitute expeditious progress.
    The Pacific walrus will be added to the list of candidate species 
upon publication of this 12-month finding. We will continue to monitor 
the status of this population as new information becomes available. 
This review will determine if a change in status is warranted, 
including the need to make prompt use of emergency-listing procedures.
    We intend that any proposed listing determination for the Pacific 
walrus will be as accurate as possible. Therefore, we will continue to 
accept additional information and comments from all concerned 
governmental agencies, the scientific community, the subsistence 
community, industry, or any other interested party concerning this 
finding.

References Cited

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

Author(s)

    The primary authors of this notice are the staff members of the 
Marine Mammals Management Office and the Fisheries and Ecological 
Services Division of the Alaska Regional Office.

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: January 21, 2011.
Rowan W. Gould,
Acting Director, Fish and Wildlife Service.
[FR Doc. 2011-2400 Filed 2-9-11; 8:45 am]
BILLING CODE 4310-55-P