Endangered and Threatened Wildlife and Plants; 12-Month Finding on a Petition To List the Yellow-Billed Loon as Threatened or Endangered, 12932-12968 [E9-6012]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 74, Number 56 (Wednesday, March 25, 2009)]
[Proposed Rules]
[Pages 12932-12968]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E9-6012]



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Part II





Department of the Interior





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Fish and Wildlife Service



50 CFR Part 17



Endangered and Threatened Wildlife and Plants; 12-Month Finding on a 
Petition To List the Yellow-Billed Loon as Threatened or Endangered; 
Proposed Rules

Federal Register / Vol. 74, No. 56 / Wednesday, March 25, 2009 / 
Proposed Rules

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[FWS-R7-ES-2009-0133; MO9221050083-B2]


Endangered and Threatened Wildlife and Plants; 12-Month Finding 
on a Petition To List the Yellow-Billed Loon as Threatened or 
Endangered

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of 12-month petition finding.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
12-month finding on a petition to list the yellow-billed loon (Gavia 
adamsii) as threatened or endangered, with critical habitat, under the 
Endangered Species Act of 1973, as amended (Act). The petitioners 
provided two listing options for consideration by the Service: (1) 
Listing the yellow-billed loon throughout its range, or (2) listing the 
United States population of the yellow-billed loon as a Distinct 
Population Segment (DPS). After a review of the best available 
scientific and commercial information, we have determined that listing 
the yellow-billed loon rangewide under the Act is warranted but 
precluded by other higher priority listing actions.

DATES: This finding was made on March 25, 2009.

ADDRESSES: This finding is available on the Internet at https://www.regulations.gov. Data, information, comments, or questions 
regarding this notice should be submitted to the Field Supervisor, 
Endangered Species Branch, Fairbanks Fish and Wildlife Field Office, 
U.S. Fish and Wildlife Service, 101-12th Ave., Room 110, Fairbanks, AK 
99701. The complete administrative file for this finding is available 
for public inspection, by appointment, during normal business hours at 
the above address.

FOR FURTHER INFORMATION CONTACT: Mr. Ted Swem, Fairbanks Fish and 
Wildlife Field Office (see ADDRESSES) (telephone 907-456-0441; 
facsimile 907-456-0208). If you use a telecommunications device for the 
deaf (TDD), call the Federal Information Relay Service (FIRS) at 800-
877-8339.

SUPPLEMENTARY INFORMATION: 

Background

    Section 4(b)(3)(B) of the Act (16 U.S.C. 1531 et seq.) requires 
that, for any petition presenting substantial scientific and commercial 
information that listing may be warranted, we make a finding within 12 
months of the date of receipt of the petition on whether the petitioned 
action is: (a) Not warranted, (b) warranted, or (c) warranted, but that 
immediate proposal of a regulation implementing the petitioned action 
is precluded by other pending proposals to determine whether species 
are threatened or endangered, and expeditious progress is being made to 
add or remove qualified species from the 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, and is, therefore, subject to a new finding to be made within 
12 months and subsequently thereafter until we take action on a 
proposal to list or withdraw our original finding. We must publish 
these 12-month findings in the Federal Register.

Previous Federal Actions

    On April 5, 2004, we received a petition from the Center for 
Biological Diversity (CBD) (Sitka, AK), Natural Resources Defense 
Council (Washington, DC), Pacific Environment (San Francisco, CA), 
Trustees for Alaska (Anchorage, AK), Kaira Club (Chukotka, Anadyr, 
Russia), Kronotsky Nature Preserve (Kamchatka Region, Russia), Taiga 
Rangers (Khabarovsk Region, Russia), Yuzhno-Sakhalinsk Local Public 
Fund (Sakhalin Region, Russia), Interregional Public Charitable 
Organization of Far Eastern Resource Centers (Vladivostok, Russia), 
Kamchatka Branch of Pacific Institute of Geography (Petropavlovsk-
Kamchatsky, Russia), and Kamchatka League of Independent Experts 
(Petropavlovsk-Kamchatsky, Russia) to list the yellow-billed loon as 
endangered or threatened throughout its range, or as a Distinct 
Population Segment in the United States, and to designate critical 
habitat once listed. The petition summarizes threats to the species 
based on CBD's review of Fair's (2002) report, prepared for the Natural 
Resources Defense Council and Trustees for Alaska, on the status and 
significance of the species in Alaska, as well as CBD's review of the 
scientific literature. In September 2006, the Service completed a 
``Conservation Agreement for the Yellow-billed Loon (Gavia adamsii)'' 
with Federal, State, and local partners. In response to the petition, 
we published a 90-day finding on the yellow-billed loon in the Federal 
Register on June 6, 2007 (72 FR 31256). In the 90-day finding we 
determined that the petition presented substantial scientific or 
commercial information to indicate that a listing may be warranted and 
announced that a status review would be promptly commenced. In that 
notice we announced the opening of a 60-day information collection 
period and invited the public to submit to us any pertinent information 
concerning the status of or threats to this species. Approximately 
28,000 comments were received during the information collection period. 
We also consulted with recognized yellow-billed loon experts and other 
Federal and State agencies. We sent letters to national wildlife or 
natural resource agencies in Canada, China, Japan, North Korea, Norway, 
Republic of Korea (South Korea), and the Russian Federation, asking for 
information about ongoing management measures and any conservation and 
management strategies being developed to protect the species. We 
received a formal response from the government of Canada, and an 
informal response from a government biologist in the Russian 
Federation.
    On June 11, 2007, we received a 60-day notice of intent to sue from 
the Center for Biological Diversity alleging a violation of section 4 
of the ESA for failure to complete a 12-month finding on the petition. 
We informed the plaintiffs by letter dated July 9, 2007, that further 
action on the petition was precluded by higher priority listing actions 
but that, pending the fiscal year 2008 allocation of funds, we hoped to 
complete the 12-month finding within that fiscal year.
    On December 19, 2007, the Center for Biological Diversity (CBD) 
filed a complaint alleging that the Service had failed to make a timely 
12-month finding on the petition, as required under section 4 of the 
ESA. Consistent with a settlement agreement reached between the Service 
and CBD, the Court ordered the Service to submit this 12-month finding 
for publication to the Federal Register by February 15, 2009. Because 
the Service later received substantial new information to be evaluated 
and considered in the 12-month finding, we subsequently sought and were 
granted a one month extension with a new deadline of March 16, 2009.
    This notice constitutes a 12-month finding for the petition to list 
the yellow-billed loon as threatened or endangered. The petitioners 
provided two listing options for consideration by the Service: (1) 
Listing the yellow-billed loon throughout its range, or (2) listing the 
United States population of the yellow-billed loon as a Distinct 
Population Segment (DPS). Because we find that listing the yellow-
billed loon rangewide is warranted at this time,

[[Page 12933]]

there is no need to conduct further analysis of whether listing the 
United States population of the yellow-billed loon as a DPS, which is a 
smaller geographic entity than the entire range, is warranted, as this 
consideration is subsumed by the rangewide warranted but precluded 
finding.

Outline of This Notice

    In this notice, we first provide background information on the 
biology of the yellow-billed loon. Next, we address each of the 
categories of factors listed in section 4(a)(1) of the Act. For each 
factor, we first determine whether any stressors, or risk factors, 
appear to be negatively affecting yellow-billed loons anywhere within 
the species' range. If we determine they are, then we evaluate whether 
each of these risk factors is resulting in population-level effects 
that are significant to the determination of the conservation status of 
the species. If so, we describe it as a ``threat.'' The fact that we 
find a stressor to be a threat to the species does not necessarily mean 
that the species meets the definition of threatened or endangered. 
Rather, in the subsequent finding section, we then consider each of the 
stressors and identified threats, individually and cumulatively, and 
make a determination with respect to whether the species is endangered 
or threatened according to the statutory standard.
    The term ``threatened species'' means any species (or subspecies 
or, for vertebrates, distinct population segments) that is likely to 
become an endangered species within the foreseeable future throughout 
all or a significant portion of its range. The Act does not define the 
term ``foreseeable future.'' However, in a January 16, 2009, memorandum 
addressed to the Acting Director of the U.S. Fish and Wildlife Service, 
the Office of the Solicitor, Department of the Interior, concluded, ``* 
* * as used in the ESA, Congress intended the term `foreseeable future' 
to describe the extent to which the Secretary can reasonably rely on 
predictions about the future in making determinations about the future 
conservation status of the species.'' In a footnote, the memorandum 
states, ``In this memorandum, references to `reliable predictions' are 
not meant to refer to reliability in a statistical sense. Rather, I use 
the words ``rely'' and ``reliable'' according to their common, non-
technical meanings in ordinary usage. Thus, for the purposes of this 
memorandum, a prediction is reliable if it is reasonable to depend upon 
it in making decisions'' (M-37021, January 16, 2009).

Species Biology

    The yellow-billed loon is a migratory bird. Solitary pairs breed on 
lakes in the arctic tundra of the United States, Russia, and Canada 
from June to September. During the remainder of the year the species 
winters in more southern coastal waters of the Pacific Ocean and the 
Norway and North Seas. Non-breeding birds remain in marine waters 
throughout the year, either in wintering areas or offshore from 
breeding grounds.
    The following information regarding the description and natural 
history of the yellow-billed loon (American Ornithologists' Union 1998, 
p. 5) has been condensed from the status assessments conducted by North 
(1994) and Earnst (2004), and updated with information that has become 
available since then.

Taxonomy and Description

    The yellow-billed loon (Order Gaviiformes, Family Gaviidae) is one 
of the largest of the five loon species and similar in appearance to 
the common loon (Gavia immer). There are no recognized subspecies or 
geographic variations (American Ornithologists' Union 1998, p. 5). A 
field characteristic that distinguishes yellow-billed loons from common 
loons is their larger yellow or ivory-colored bill. Adults weigh 4,000 
to 6,000 grams (8.8 to 13.2 pounds) and are 774 to 920 millimeters (30 
to 37 inches) in length. Breeding (alternate) plumage of adults of both 
sexes is black on top with white spots on the wings and underside, and 
white stripes on the neck. Non-breeding (basic) plumage is gray-brown 
with fewer and less distinct white spots than breeding plumage, with 
paler undersides and head, and a blue-gray bill. Hatchlings have dark 
brown and gray down, and juveniles are gray with a paler head (North 
1994, p. 2). Yellow-billed loons are specialized for aquatic foraging 
with a streamlined shape and legs near the rear of the body, and are 
unable to take flight from land.

Feeding Habits

    Yellow-billed loons forage underwater for fish and aquatic 
invertebrates. Limited information exists on specific prey species 
consumed. Marine prey species collected from loons wintering in 
southeast Alaska and Canada include fish such as sculpins (Leptocottus 
armatus, Myoxocephalus sp.), Pacific tomcod (Microgadus proximus), and 
rock cod (Sebastodes sp.), and invertebrates such as amphipods 
(Orchomonella sp., Anonyx nirgax), isopods (Idothea sp.), shrimps 
(Pandalus danae, Spirontocaris ochotensis), hermit crabs (Pagarus sp.), 
and marine worms (Nereis sp.) (Bailey 1922, p. 205; Cottam and Knappen 
1939, p. 139; North 1994, pp. 6-7; Earnst 2004, pp. 9-10). Pacific sand 
dabs (Citharichthys sordidus) were found in a yellow-billed loon 
collected extralimitally (i.e., outside the limits of the species' 
range) in Baja California (Jehl 1970, p. 376) and sculpin 
(Myoxocephalus scorpius) in a specimen collected in Norway (Collett 
1894, p. 280). Prey species taken in other wintering grounds, such as 
in the Yellow Sea (which supports 276 fish species and 54 crustacean 
species; UNDP 2002, p. 8) are unknown.
    During the breeding season, foraging habitats include lakes, 
rivers, and the nearshore marine environment. Successfully breeding 
adults feed their young almost entirely from the brood-rearing lake 
(North 1994, p. 14). Ninespine sticklebacks (Pungitius pungitius) and 
least cisco (Coregonus sardinella) are thought to be the main foods of 
chicks in Alaska (Earnst 2004, p. 9). Other freshwater prey available 
in Alaska that are likely utilized include Alaska blackfish (Dallia 
pectoralis), fourhorn sculpins (M. quadricornus), amphipods, and 
isopods (Earnst 2004, p. 9), as well as aquatic plant material 
(Sj[ouml]lander and [Aring]gren 1976, p. 460). In arctic Russia, 
limited stomach content analysis indicates sticklebacks, salmon, 
crustaceans, beetles, and plant vegetation are consumed during the 
breeding season (Uspenskii 1969, p. 130).

Breeding Habitat and Territories

    Yellow-billed loons nest exclusively on margins of lakes in coastal 
and inland low-lying tundra from 62[deg] to 74[deg] North (N) latitude. 
Lakes that support breeding loons have abundant fish populations. 
Studies of yellow-billed loon habitat have identified several 
characteristics that predict loon presence. These may be indirect 
measures or correlates of the actual characteristics necessary or 
preferred by loons, such as fish availability. Predictors of yellow-
billed loon presence on a lake include water depths greater than 2 
meters (m) or 6.5 feet (ft) allowing for unfrozen water under the ice 
during winter; large lake areas (at least 13.4 hectares (ha) or 33 
acres (ac)); connections to streams that may supply fish; highly 
convoluted, vegetated, and low-lying shorelines; clear water; and 
dependable water levels (Earnst et al. 2006, pp. 230-233; Stehn et al. 
2005, pp. 9-10; North 1994, p. 6). Probability of yellow-billed loon 
presence on a lake increases with the absence of Pacific

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loons (Gavia pacifica) (Earnst et al. 2006, p. 233; Stehn et al. 2005, 
p. 9). Breeding lakes may be near major rivers, but are usually not 
connected to them, possibly because greater fluctuations associated 
with river connections may flood nests or cause turbidity that 
compromises foraging success (North & Ryan 1989, p. 303). Falling water 
levels may also expose loon nests to increased risk of predation 
(Kertell 1996, p. 356).
    Breeding territories (areas defended against other yellow-billed 
loons and other loon species, particularly Pacific loons) may include 
one or more lakes or parts of lakes. Territory size, likely dependent 
upon lake size and quality, ranged from 13.8 to greater than 100 ha (34 
to greater than 247 ac) on the Colville River Delta, Alaska (North 
1986, as cited in North 1994, p. 10). It is thought that individual 
loons occupy the same breeding territory throughout their reproductive 
life. Some breeding lakes are ``known to be reoccupied over long time 
spans'' (North 1994, p. 10), most likely by the same monogamous pair 
(North 1994, p. 10), similar to common loons (Evers 2004, p. 13).

Nesting Sites and Behavior

    Nest sites are usually located on islands, hummocks, or peninsulas, 
along low shorelines, within 1 m (3 ft) of water. The nest location, 
which may be used in multiple years, usually provides a better view of 
the surrounding land and water than other available lakeshore 
locations. Nests are constructed of mud or peat, and are often lined 
with vegetation. One or two large, smooth, mottled brown eggs are laid 
in mid-to late June (North 1994, pp. 11-12). Egg replacement after nest 
predation occurs rarely; unless failure occurs very early in the 
season, the short arctic summer probably precludes the production or 
success of replacement clutches (Earnst 2004, p. 8). Hatching occurs 
after 27 to 28 days of incubation by both sexes. Although the age at 
which young are capable of flight is unknown, it is probably similar to 
common loons (8-9, possibly up to 11, weeks). The young leave the nest 
soon after hatching, and the family may move between natal and brood-
rearing lakes. Both males and females participate in feeding and caring 
for young (North 1994, p. 13).

Life History

    There is no reliable scientific information on lifespan and 
survivorship, but as large-bodied birds with low clutch size, yellow-
billed loons are probably K-selected (long-lived and dependent upon 
high annual adult survival to maintain populations). On average, 
individuals reach sexual maturity at 3 years of age, but may not 
acquire breeding territories until at least 4 years of age (North 1994, 
p. 15). The average age at first breeding for common loons is 6 years 
(Evers 2004, p. 18).
    Territory occupancy and nesting success of yellow-billed loons were 
studied on the Colville River Delta during 18 years between 1983 and 
2007. Ground-based surveys in 1983 and 1984 found 76 and 79 percent of 
the territorial pairs nesting, respectively (Field et al. 1993, p. 
329). The same territories studied in 1983 and 1984 were visited in 
1989 and 1990, and 42 percent and 67-71 percent, respectively, of the 
territorial pairs were found nesting (Field et al. 1993, p. 329; North 
1993, p. 46). Low nest occupancy recorded in 1989 may have been a 
result of surveys being conducted late in incubation (July 9-16, 1989) 
after nests of some pairs had already failed; weekly monitoring surveys 
of nesting yellow-billed loons on the Colville River Delta in 2005-2007 
found that 19-36 percent of the nests had failed by July 10-12 of those 
years (Johnson et al. 2006, Table 5; Johnson et al. 2007, Table 5; 
Johnson et al. 2008, Table 4). However, low nest occupancy occurred in 
some years during two long-term studies of yellow-billed loons on the 
Colville Delta. The percentage of territorial pairs nesting ranged from 
39 percent to 89 percent during a 6-year ground-based study (1995-2000; 
Earnst 2004, p. 9) and from 43 percent to 76 percent (average of 58 
percent) during 13-years of aerial surveys (1993-2007; ABR, Inc. 2007, 
Table 1; ABR, Inc., unpublished data).
    Reproductive success, like nest occupancy by territorial pairs, 
varied on the Colville River Delta. Low reproductive success has been 
attributed to late ice melt or extreme flooding (Earnst 2004, p. 9). 
Based on Mayfield survival rates (a technique for measuring nesting 
success in which the number of days from discovery of the nest to 
fledging or failure (exposure days) is used to compute a daily nest-
survival rate) calculated for yellow-billed loons nesting on the 
Colville River Delta in 1995-2000, 4 percent to 60 percent of eggs/
chicks survived from laying to age 6 weeks (Earnst 2004, p. 9). 
Apparent nesting success [(broods/nests) x 100] based on broods counted 
on aerial surveys conducted 8 weeks apart during nesting and brood-
rearing ranged from 19 percent to 64 percent annually in 13 years 
between 1993 and 2007 (ABR, Inc. 2007, Table 1; ABR, Inc., unpublished 
data). During the last three years (2005-2007) of this study, weekly 
monitoring surveys were conducted after nests were found. Apparent 
nesting success calculated from these weekly surveys was 1-10 percent 
higher than calculations based on nesting and brood-rearing surveys 
conducted 8 weeks apart, because the more frequent surveys identified 
nests with chicks that did not survive to 5-6 weeks of age (Johnson et 
al. 2006, p. 17; Johnson et al. 2007, p. 16; Johnson et al. 2008, p. 
15). The highest recorded apparent nesting success on the Colville 
River Delta was 71 percent in 2007 based on weekly monitoring surveys 
(Johnson et al. 2008, p. 15).

Breeding Distribution

    Yellow-billed loons nest near freshwater lakes in arctic tundra of 
Alaska on the Arctic Coastal Plain (ACP), northwestern Alaska, and St. 
Lawrence Island; in Canada east of the Mackenzie Delta and west of 
Hudson Bay; and in Russia on a relatively narrow strip of coastal 
tundra from the Chukotka Peninsula in the east and on the western 
Taymyr Peninsula in the west, with a break in distribution between 
these two areas (Earnst 2004, p. 3; North 1993, p. 42; Red Data Book of 
the Russian Federation 2001, p. 366; Ryabitsev 2001, p. 22; Il'ichev 
and Flint 1982, p. 277; Pearce et al. 1998, p. 369). Loons are sparsely 
distributed across their range, although, perhaps because of non-
uniform quality of habitat, at a large scale breeding birds are 
somewhat clumped in distribution.

Breeding Bird Densities

    Most of the breeding range of the yellow-billed loon has not been 
adequately surveyed, and only in Alaska have surveys been conducted 
specifically for breeding yellow-billed loons. Unless otherwise noted, 
the following discussion includes data from waterfowl surveys for which 
loons were not focal species. In these surveys, density estimates were 
not corrected for visibility bias and so are minimal estimates (see 
discussion in Groves et al. 1996, pp. 193-194). Surveys enumerate all 
yellow-billed loons seen on breeding grounds, including an unknown 
proportion of which are non-breeders (Earnst et al. 2005, p. 300).
Alaska
    Based on fixed-wing aerial survey data (1992 to 2003 ACP and North 
Slope Eider (NSE) surveys conducted by the Service), Earnst et al. 
(2005, p. 300) calculated that most of the population on the ACP of 
Alaska occurred within concentration areas with more than 0.11 
individuals per square kilometer (km2). Such areas comprised 
only 12 percent of the surveyed area yet contained 53 percent of 
yellow-billed loon sightings.

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The largest concentration area was between the Meade and Ikpikpuk 
Rivers; it covered only 8 percent of the survey area, but had 38 
percent of yellow-billed loon sightings (Earnst et al. 2005, p. 300). 
Other notable concentrations were on the Colville River Delta and west, 
southwest, and east of Teshekpuk Lake (Earnst et al. 2005, p. 300). In 
aerial lake-circling surveys designed for yellow-billed loons (fixed-
wing aircraft were used 1992-2000; helicopters were used 2001-2007), 
the average density on the Colville River Delta (363 km2 
(140 mi2) survey area) was 0.13 individuals per 
km2 during 10 years from 1993 to 2004 (Johnson et al. 2005, 
p. 65), and 0.15 to 0.17 individuals per km2 from 2005 to 
2007 (Johnson et al. 2006, p. 15; Johnson et al. 2007, p. 16; Johnson 
et al. 2008, p. 15). Similar surveys for yellow-billed loons in a 
larger area (878 km2) (339 mi2) in the Northeast 
Planning Area (NE) of the National Petroleum Reserve-Alaska (NPR-A) in 
2001-2004 indicated densities there were lower (0.07 individuals/
km2; Johnson et al. 2005, p. 68), except that the density in 
an area adjacent to Fish and Judy Creeks was similar to that of the 
Colville River Delta (Johnson et al. 2005, p. 68; Johnson et al. 2006, 
p. 15; Johnson et al. 2007, p. 16). In western Alaska, where fixed-wing 
aerial surveys were also designed specifically for loons, density on 
the northern Seward Peninsula averaged 0.058 (standard error 
(SE)=0.011; standard error is a measure of the variability in the data) 
individuals/km2 over 2 years (Bollinger et al. 2008, p. 5).
Canada
    In Canada, concentrations are found on parts of Victoria and Banks 
Islands, on the mainland, the Kent Peninsula, east of Bathhurst Inlet 
and west of Ellice River, the west side of Boothia Peninsula, and the 
lake district between Great Slave Lake and Baker Lake, including the 
Thelon Game Sanctuary (North 1993, p. 42). Densities obtained in 2005 
and 2007 from fixed-winged aerial waterfowl surveys on southern 
Victoria Island and the Kent Peninsula ranged from 0.017 to 0.16 birds/
km2 (Conant et al. 2006, pp. 2, 7; Groves in litt. 2008); 
lower densities (0.004-0.027 birds/km2) were found in 
surveys on the Queen Maud Gulf Migratory Bird Sanctuary, King William 
Island, Rasmussen Lowlands, and Kugluktuk (Conant et al. 2007, pp. 10, 
12; Groves in litt. 2008). On western Victoria Island, Raven and 
Dickson (2006, p. 24) estimated densities from 0.004 to 0.08 birds/
km2 from helicopter-based waterfowl surveys. Hines (in litt. 
2008) estimated 0.01 yellow-billed loons/km2 on Banks Island 
from helicopter-based waterfowl surveys in 1992 and 1993.
Russia
    In Russia, breeding concentrations have been identified on the 
Chukotka (Chukotskiy) Peninsula (Il'ichev and Flint 1982, p. 280; 
Solovyov 1992, p. 21), Kyttyk Peninsula and Ayon Island in western 
Chukotka (Solovyova 2007, p. 6), and the western Taymyr Peninsula 
(Krechmar 1966, p. 200; Il'ichev and Flint 1982, p. 277). Hodges and 
Eldridge (2001, pp. 141-142), using fixed-winged aircraft in the only 
aerial waterfowl survey of the eastern Siberian coast, found 
concentrations of approximately 0.01 birds/km2 on the Cape 
Schmidt coast of the Chukotka Peninsula, between the Indigirka and Yana 
River Deltas, and between the Indigirka and Kolyma Deltas. Post-
breeding density on Kyttyk Peninsula in western Chukotka was 
approximately 0.52 birds/km2 (including young birds) during 
late July-August 2003-2007 (calculated from ground surveys, Solovyova 
2007, p. 6). No density estimates are available for the Taymyr 
Peninsula.

Nest Densities

    Nest density on 363 km2 (140 mi2) of the 
Colville River Delta, Alaska, ranged from 0.03 to 0.08 nests/
km2 during 13 years of aerial surveys for yellow-billed 
loons during 1993-2007 (Johnson et al. 1999, p. 44; Burgess et al. 
2003, p. 36; Johnson et al. 2003, p. 43; Johnson et al. 2004, p. 74; 
Johnson et al. 2005, p. 64; Johnson et al. 2006, p. 15; Johnson et al. 
2007, p. 16; Johnson et al. 2008, p. 15). Nest density in an 878 
km2 (339 mi2) survey area of NE NPR-A was 0.03 
nests/km2 in each year during 2002-2004. Higher densities 
within this area were found along Fish and Judy Creeks (helicopter-
based surveys; Johnson et al. 2005, p. 68). In Russia, Solovyov (1992) 
reported 0.18 nests/km2 on a 27.6 km2 (10.6 
mi2) plot searched from the ground on Belyaka Spit near 
Kolyuchin Bay on the Chukotka Peninsula. On the Kyttyk Peninsula in 
western Chukotka, yellow-billed loons nest on approximately 25 percent 
of lakes larger than 4 ha (9.9 acres) (Solovyova 2007, p. 6).

Foraging Distribution During Breeding Season

    Yellow-billed loons use nearshore and offshore marine waters 
adjacent to their breeding areas for foraging in summer. Such habitats 
are likely used by both breeding adults and younger or non-territorial 
birds (Earnst 2004, p. 7). Earnst (2004, pp. 6-7) reviewed yellow-
billed loon distribution information from fixed-wing aerial waterfowl 
surveys that Fischer et al. (2002) conducted in 1999 and 2000 off the 
coasts of Canada's arctic islands and the ACP of Alaska between Cape 
Halkett and Brownlow Point. Similar surveys conducted between Barrow 
and Demarcation Point in 2001 also included yellow-billed loon 
observations in Elson Lagoon (Fischer 2001, p. 4; Fischer and Larned 
2004, p. 146). During fixed-wing aerial surveys for common eiders in 
late June of 1999 through 2007, between 23 and 99 yellow-billed loons 
were observed in nearshore waters and along barrier islands of the 
Beaufort and Chukchi Seas (Dau and Larned 2007, p. 18). Yellow-billed 
loons used lagoons and nearshore waters along the coast of St. Lawrence 
Island in summer in the 1950s (Fay and Cade 1959, pp. 92, 100). In 
Russia, Solovyova (coastal boat surveys; 2007, p. 6) reported densities 
of 0.24 birds/km\2\ using coastal waters near the Kyttyk Peninsula and 
Ayon Island at the northern end of Chaun Bay in western Chukotka, and 
0.04 birds/km\2\ at the southern end of Chaun Bay near the Chaun River 
Delta in 2006. Vronskiy (1987, p. 30) observed individual yellow-billed 
loons and pairs in bays 100-150 m (328-492 ft) offshore of northwestern 
Taymyr during summer. Yellow-billed loons occurred in summer along the 
coast of Wrangel Island, although there were no indications of nesting 
on the island (Stishov et al. 1991, p. 20). In boat-based surveys in 
the Kara and Barents Seas, arctic (Gavia arctica) and red-throated (G. 
stellata) loons were abundant in the nearshore marine waters of the 
western Kara Sea and in the Ob' and Yenisey estuaries, especially in 
Baidaratskaya Bay, and occurred in smaller numbers in the Pechora Bay 
in the Barents Sea in August and September 1995, but no yellow-billed 
loons were observed (Decker et al. 1998, pp. 9, 11). In subsequent boat 
surveys between 1998 and 2003, only one yellow-billed loon was observed 
in mid-August 1998 in coastal waters northeast of Dolgy Island (west of 
Vaigach Island) in the Pechora Sea (M. Gavrilo, in litt. 2008).

Wintering Habitat and Distribution

    Wintering habitats include sheltered marine waters less than 30 m 
(98.4 ft) deep, such as fiords and areas between islands on the inner 
coast in Norway (Strann and [Oslash]stnes 2007, p. 2). Schmutz (2008, 
p. 1) found that throughout migrating and wintering seasons, yellow-
billed loons marked with satellite transmitters occurred from 1 to 20 
miles offshore. The wintering range includes coastal waters of southern 
Alaska and British Columbia from the Aleutian Islands to Puget Sound; 
the

[[Page 12936]]

Pacific coast of Asia from the Sea of Okhotsk south to the Yellow Sea; 
the Barents Sea and the coast of the Kola Peninsula; coastal waters of 
Norway; and possibly Great Britain (Earnst 2004, pp. 13-14; North 1993, 
pp. 42-43; Ryabitsev 2001, p. 22; Schmutz in litt. 2008, p. 1; Strann 
and [Oslash]stnes 2007, p. 2; Burn and Mather 1974, p. 278; Gibson and 
Byrd 2007, p. 68). A small proportion of yellow-billed loons may winter 
in interior lakes or reservoirs in North America (North 1994, p. 3).
    Winter population distribution and numbers of yellow-billed loons 
are not well documented, but some information is available from marine 
bird surveys. Earnst (2004, p. 14) summarized loon observations in 
boat-based marine bird population surveys in Lower Cook Inlet, Prince 
William Sound, and Kodiak Island. In these surveys, estimates of 
yellow-billed loons were in tens to low hundreds, with wide confidence 
limits. In many cases, loons were not identified to species. Strann and 
[Oslash]stnes (2007, p. 3) counted 1,160-1,605 yellow-billed loons on 
surveys conducted off the coast of Norway from 1986 to 1994, confirming 
Norway as the most important known wintering area for the species in 
Europe. No surveys have been conducted in Asian wintering areas. In 
some regularly used wintering areas such as the Yellow Sea, the 
Aleutian Islands, and Great Britain, the yellow-billed loon's small 
population and scattered marine distribution may have contributed to 
the impression that yellow-billed loons are vagrants or rare visitors 
(Lepage 2008, p. 1; Gibson and Byrd 2007, p. 68; Dudley et al. 2006, p. 
533; Scott and Shaw 2008, pp. 241-248).
    Immature loons and possibly some non-breeding adults stay in 
wintering areas throughout the year (North 1994, p. 4). Earnst (2004, 
pp. 11-12) summarized yellow-billed loon observations in summer marine 
boat-based surveys conducted in lower Cook Inlet and Prince William 
Sound in southcentral Alaska, and in southeast Alaska. Estimates from 
all these surveys totaled only 339 yellow-billed loons, but many loons 
were not identified to species (Earnst 2004, p. 11). In boat-based 
surveys of murrelets conducted in July of 2002-2004 from Icy Bay to 
LeConte Bay in southeast Alaska, Kissling et al. (2007, Appendices 7, 
8) counted 20 yellow-billed loons. Yellow-billed loons have been 
observed throughout summer months in the Aleutians (Gibson and Byrd 
2007, p. 68). According to the Red Data Book of Kamchatka (2006, p. 
92), non-breeding birds occur off the coast of Kamchatka in summer.

Migration

    Yellow-billed loon migration routes are thought to be primarily 
marine. Schmutz (in litt. 2008, p. 1) found that yellow-billed loons 
marked with satellite transmitters generally remained between 1 and 20 
miles from land during migration and winter. Yellow-billed loons 
migrate singly or in pairs, but gather in polynyas (areas of open water 
at predictable, recurrent locations in sea-ice covered regions), ice 
leads (more ephemeral breaks in sea ice, often along coastlines), and 
early-melting areas off river deltas near breeding grounds in spring 
along the Beaufort Sea coast of Alaska and Canada (Barry et al. 1981, 
pp. 29-30; Barry and Barry 1982, p. 25; Woodby and Divoky 1982, p. 406; 
Johnson and Herter, 1989, p. 9; Barr 1997, pp. 12-13; Alexander et al. 
1997, pp. 15, 17; Mallory and Fontaine 2004, pp. 52-53).
    These observations of yellow-billed loons in the Beaufort Sea 
during migration establish that at least some yellow-billed loons 
breeding in Canada's Arctic Islands and along the adjacent Canadian 
coast use this migration route. North (1993, pp. 45-46) examined 
evidence of alternative migration routes for yellow-billed loons 
wintering in southeast Alaska and British Columbia, suggesting that 
they could migrate overland to mainland breeding areas in Canada, 
particularly around Great Slave Lake. Yellow-billed loons have been 
observed on inland lakes in Canada and Alaska (North 1993, pp. 43, 46). 
The existence of this route is still hypothetical, and the number of 
yellow-billed loons in interior mainland Canada is highly uncertain 
(discussed below under Population Size).
    Yellow-billed loons breeding in Alaska have been studied to 
determine migration routes. Nineteen yellow-billed loons captured on 
the ACP between 2002 and 2008 were outfitted with satellite 
transmitters (Schmutz in litt. 2008, p. 1). All of them migrated to 
Asia, predominantly south along the Russian coastline from the Chukotka 
Peninsula (either through the Bering Strait or across the mountains 
from the north side of the Chukotka Peninsula to the Gulf of Anadyr), 
and along the Kamchatka coast. They wintered in the Yellow Sea and Sea 
of Japan off China, North Korea, Russia, and Japan (near Hokkaido). All 
10 yellow-billed loons fitted with transmitters on the Seward 
Peninsula, Alaska, in 2007 and 2008 also used the Bering Strait region 
after leaving breeding grounds. Five of these migrated to Asian grounds 
as described above for ACP breeding birds; the other 5 wintered 
throughout the Aleutian Islands from Shemya Island in the west to the 
Semidi Islands off the coast of the Alaska Peninsula (Schmutz in litt. 
2008, p. 1). Most of these yellow-billed loons departed breeding areas 
in late September, arrived in wintering locations in mid-November, 
started spring migration in April, and arrived on breeding grounds in 
the first half of June; these dates are consistent with breeding ground 
arrival dates reported by North (1994, p. 5). Non-breeders or failed 
nesters may start fall migration in July.
    The migration routes of yellow-billed loons breeding in Russia have 
not been studied. Because of the proximity of the Chukotka Peninsula to 
the ACP in Alaska, and the fact that ACP breeding yellow-billed loons 
use the Chukotka Peninsula during migration (Schmutz in litt. 2008, p. 
1), it is likely that some or all yellow-billed loons from eastern 
Russia migrate through the Bering Strait to Asian wintering areas.

Population Size

ACP, Alaska
    Yellow-billed loon population indices on the ACP of Alaska were 
determined by two independent fixed-wing aerial transect surveys 
conducted each year by the Service's Migratory Bird Management program. 
Surveys were flown in early June each year from 1992 through 2008 (NSE 
survey, 1992-2008, an average of 1,304 km\2\ (503.5 mi\2\) transect 
area that sampled a total area of 30,465 km\2\ (11,763 mi\2\), for 4.3 
percent coverage) and late June each year from 1986 through 2006 (ACP 
survey, 1986-2006, average of 1,256 km\2\ (485 mi\2\) transect area 
which sampled a total area 61,645 km\2\ (23,801 mi\2\), for 2.0 percent 
coverage of a larger area than that covered by the NSE survey). The 
average population index from the NSE survey is 1,119 yellow-billed 
loons (95 percent confidence interval (CI) = 1,012 to 1,226, Larned et 
al. 2009, p. 24). (Note: In order to estimate the reliability of a 
sample statistic, such as an average, it is common to set confidence 
limits to it (Sokal and Rohlf 1995, p. 139). The limits will show the 
maximum and minimum numbers the statistic (e.g., average) is likely to 
be, along with a measure of that likelihood (e.g., 95 percent). So, 
when an average number of birds, for example, is reported, followed by 
a confidence interval, the confidence interval shows the statistical 
range of values that provides cutoff points for the likely values for 
the average.) The long-term mean from the ACP survey is 2,611 loons (95 
percent CI = 2,218 to 3,005; Mallek et al. 2007, p. 10; USFWS 
unpublished data). The

[[Page 12937]]

confidence intervals around these 16- and 21-year means incorporate the 
variation due to within-year sampling error, the spatial variability 
among transects and within strata, and variation among years related 
either to detection rate (observer ability, habitat change, weather 
conditions) or the availability of birds to be seen (arrival or 
departure of population components, behavior associated with nesting 
chronology). One study integrated results from both the early and late 
surveys, incorporating covariates adjusting for detection rates (Earnst 
et al. 2005). The 12-year mean (1992 through 2003) resulted in an 
estimate of 2,221 individuals (95 percent CI = 1,209-3,233) in early 
June and 3,369 individuals (95 percent CI = 1,910-4,828) in late June 
(Earnst et al. 2005, p. 295). Another estimate of population size was 
determined by lake-circling aerial searches of greater than 7-ha (17.3-
acre) lakes on 7 x 7-km (4.35 x 4.35-mi) plots as part of a 2003-2004 
study of yellow-billed loon habitat preferences (Stehn et al. 2005, pp. 
1-37). This survey was flown from June 15 through 22 each year. Based 
on average density observed, the estimated total population index was 
2,544 (95 percent CI = 1,780-3,308) yellow-billed loons (Stehn in litt. 
2008, p. 1).
Western Alaska
    Seward Peninsula and Cape Krusenstern fixed-wing aerial lake-
circling surveys, on 12 x 12-km (7.46 x 7.46-mi) sample plots, were 
flown in June of 2005 and 2007, and resulted in an estimate of 431 (95 
percent CI = 280-582) yellow-billed loons on these western Alaska 
breeding grounds (Bollinger et al. 2008, p. 1). Additional aerial 
transects sampling an area of 15,234 km\2\ (5,882 mi\2\) were flown on 
Selawik National Wildlife Refuge and adjacent wetlands in June in the 
years 1996 and 1997 (Platte 1999, p. 3), but only three yellow-billed 
loons were sighted, resulting in an estimated mean population index of 
44 birds (95 percent CI = 0-95) (USFWS unpublished data). Yellow-billed 
loons were documented nesting on St. Lawrence Island in the 1950s (Fay 
and Cade 1959, pp. 84, 100), but there is no more recent information. 
Adding western Alaska population figures to those from the ACP results 
in an estimated total of 3,000 to 4,000 yellow-billed loons on breeding 
grounds in Alaska.
Canada
    Although overall breeding population estimates for yellow-billed 
loons in Canada do not exist (https://www.bsc-eoc.org/clls-bw1.html, 
accessed May 19, 2008), and yellow-billed loons are not summarized in 
the Waterfowl Population Status annual reports compiled by the U.S. and 
Canadian governments for North American Waterfowl (USFWS 2007, pp. 1-
62), several recent fixed-wing aerial waterfowl surveys included loon 
observations in parts of Nunavut and Northwest Territories. Loons were 
not the focus of the surveys, so it is possible that observer effort or 
identification ability varied, and no visibility correction factors or 
seasonal timing factors were applied. Helicopter surveys yielded 
estimates ranging from 659 (SE 359) to 1,784 (SE 502) on northwest 
Victoria Island, and from 98 (SE 70) to 258 (SE 146) birds in the 
southwest part of the island (Raven and Dickson 2006). A fixed-winged 
survey included Kent Peninsula and southeastern Victoria Island in 
2005, and Queen Maud Gulf, King William Island, Rasmussen Lowlands, and 
near Kugluktuk in 2006; all areas from both years were repeated in 2007 
but with fewer transects sampled per unit area. The combined estimate 
for both areas from 2005-2006 fixed-winged surveys and the 2007 
estimate were similar, at 2,500-3,000 birds (Conant et al. 2006, p. 7; 
Conant et al. 2007, p. 12; Groves in litt. 2008). Hines (in litt. 2008) 
estimated there were 500-1,000 yellow-billed loons on Banks Island, 
based on helicopter aerial surveys conducted in 1992 and 1993. The 
range of these point estimates suggests that between 3,750-6,000 birds 
occur on breeding grounds in the surveyed areas.
    The rest of the yellow-billed loon's range on the Canadian mainland 
has not been surveyed. Based on the vast number of large, fish-bearing 
lakes north of treeline (an area of 500,000-750,000 km\2\) (193,051-
289,577 mi\2\) minus the surveyed areas on the mainland (46,000 km\2\), 
(17,761 mi\2\) and using opportunistic observations of yellow-billed 
loons by Northwest Territory and Nunavut checklist survey cooperators 
over the last decade, Poter (in litt. 2008, p. 2, adjusted from Hines 
in litt. 2008, p. 1) calculated that a density of 0.01-0.02 birds/km\2\ 
would yield an estimate of 4,500-14,000 birds in mainland breeding 
areas in Canada, not including surveyed areas in the arctic described 
in the previous paragraph. This estimate is based on a very large land 
area bounded at the southern end by an area of documented yellow-billed 
loon breeding between Great Slave Lake and Baker Lake, particularly in 
or near the Thelon Game Sanctuary (North 1993, p. 42). Between this 
area and the arctic coast is a large area where breeding has not been 
documented (North 1993, Figure 2). Fair (2002, p. 30) estimated the 
yellow-billed loon population on interior Canadian breeding grounds to 
be 4,800, using a density of 0.02 loons in a 100,000 km\2\ area around 
the Sanctuary, and a lower density of 0.007 for the wider area of 
400,000 km\2\. Fair's estimate of 4,800 is close to the lower end of 
Poter's (2008, p. 1) estimate of 4,500. We believe Fair's analysis more 
accurately reflects likely yellow-billed loon distribution in Canada, 
because it reflects a lower average density for the large area where 
breeding has not been documented. Combining the 4,500 to 14,000 
breeding birds estimated for interior Canada, and 3,750 to 6,000 
breeding birds estimated for the arctic (and rounding to thousands), we 
conclude that the Canadian breeding population size is 8,000 to 20,000, 
but that it is most likely at the lower end of this range.
Russia
    Information on the breeding-ground population size of yellow-billed 
loons for Russia is limited. Hodges and Eldridge (2001, Appendix 2) 
estimated 674 yellow-billed loons (coefficient of variation (C.V., a 
measure of dispersion in a probability distribution) 0.55) in a 
157,611-km\2\ (60,854-mi\2\) fixed-wing aerial survey area of the 
eastern Siberia arctic coast from Kolyuchin Bay to the Lena River 
Delta. We know of no other loon surveys within the breeding range of 
the yellow-billed loon in Russia. Red Data Books for the Russian 
Federation (2001, pp. 366-367), Yakutia (1987, p. 33), and the Northern 
Far East of Russia (1998, pp. 97-98) do not offer population estimates. 
Kondratiev (1989, p. 37) estimated that 2,000 birds nested in Chukotka, 
but did not give a basis or sources for his estimate. Fair (2002, p. 
31) projected, based on this estimate of 2,000 birds in Chukotka 
(Kondratiev 1989, p. 37), that another 2,000 nested on the Taymyr 
Peninsula, and that perhaps another 1,000 were scattered across the 
arctic coast, giving 5,000 birds on Russian breeding areas. 
Syroechkovsky (in litt. 2008) suggested (based on field observations 
but not scientific surveys) that the number of birds on breeding 
grounds (including non-breeding birds) is around 3,000 for Chukotka, 
500 for Yakutia, and about 1,200 for Taymyr, for a total of around 
4,700 birds. However, Solovyova (in. litt. 2008, p. 1; calculated from 
Solovyova 2007, p. 6) recently estimated the post-breeding population 
of the Kyttyk Peninsula on Chaun Bay in western Chukotka at 1,000, and 
the post-breeding population of nearby Ayon Island at 900 birds. Given

[[Page 12938]]

Solovyova's (in. litt. 2008, p. 1) estimates for her study area in 
Chukotka, she estimated that the total breeding ground population in 
Chukotka might be as high as 5,000 birds. If the Chukotka population is 
5,000, the total for Russia could be as high as 8,000 based on habitat 
availability. Thus, our best information suggests the Russian breeding 
population is between 5,000 and 8,000 birds.
    In summary, the global breeding ground population size for yellow-
billed loons is unknown, but probably at the lower end of the range of 
16,000 to 32,000. The Alaska population estimate of 3,000 to 4,000 is 
derived from surveys. Less certain estimates based on the amount of 
available habitat (plus limited survey data) are the lower end of the 
range of 8,000 to 20,000 birds in Canada, and 5,000 to 8,000 in Russia.

Population Trend

Alaska
    The only population trends available for yellow-billed loons 
breeding in Alaska are on the ACP, where the ACP and NSE waterfowl 
surveys are conducted. We note that because we count only the breeding 
component of the population, the total population could decline without 
being detected for a number of years. This could occur because 
increased mortality of breeding birds could be masked by movements of 
birds without territories (either sub-adult birds or adults which have 
not found territories) into vacated territories. With this caution, we 
believe the time series of at least 17 years for the surveys described 
below gives us a reasonably reliable data set for observing population 
trends, and these data represent the best information available at this 
time.
    A population growth rate, or lambda, less than 1.00 would indicate 
population decline (negative ``growth''), while a lambda greater than 
1.00 would indicate population growth. For the ACP survey 1986-2006, 
the average growth rate was 0.9886 (95 percent CI = 0.9625-1.0154) 
(Mallek et al. 2007, p. 21), and for the NSE survey 1992-2008 (a 
smaller area than that covered by the ACP survey, and surveyed earlier 
in June), the average growth rate was 1.016 (95 percent CI = 0.995-
1.036) (calculated from Larned et al. 2009, Figure 1). Thus, these 
surveys provide slightly conflicting perspectives, with one suggesting 
a stable or slightly declining population (with a point estimate of a 
decline of 1.1 percent/yr.) and the other suggesting a stable or slight 
increasing population (with a point estimate of an increase of 1.6 
percent/yr.) on the ACP.
    Earnst et al. (2005, pp. 289-304) sought to improve the estimates 
above by using a statistical model that takes into account possible 
confounding factors of survey type, spring timing, and observer 
experience. They used this model to analyze ACP and NSE survey data 
through 2003. Controlling for these confounding factors, they (p. 298) 
estimated average population growth rate to be 0.991 (95 percent CI = 
0.964-1.018), also indicating a stable or slightly declining 
population.
    We also examined a subset of the NSE data through 2008 that 
included only the observations of the most consistent and experienced 
pilot-observer, who has flown all 16 early-June NSE surveys during 
1992-2008. Each survey includes observations of two observers: the 
pilot-observer in the left-side seat of the aircraft, and a second 
observer in the right-side seat. There have been numerous ``right-side 
observers'' over the course of the NSE survey. Each of these observers 
has a different ability to see and identify birds, and this ability 
often increases over successive surveys as the observer gains 
experience. Our analysis of the left-side pilot-observer eliminated the 
necessity to estimate the variable magnitudes of influence of right-
side observer experience. In addition, the increased interest in 
yellow-billed loons in 2002 may have influenced new right-side 
observers to search more intensively for yellow-billed loons than 
earlier observers, who focused on waterfowl. Our analysis of the pilot-
observer data from the NSE survey also eliminated the need to reconcile 
the later timing and different survey extent of the ACP survey. The 
average growth rate using this subset of data was slightly lower and 
more precisely estimated at 0.986 (95 percent CI = 0.967-1.006) (USFWS 
unpublished data) than the estimate of 0.991 from Earnst et al.'s 
(2005, p. 298) model, and the results also indicate a relatively stable 
or slightly declining population.
    In summary, the information available from the ACP does not allow 
us to precisely determine current population trends. Two surveys and 
multiple analytical approaches used to control for confounding factors 
provide estimates indicating trends ranging from slightly increasing to 
slightly decreasing, and all estimates have 95 percent CIs that include 
a lambda of 1.0, indicating that possible trends cannot be 
distinguished from population stability with reasonable certainty. 
Although the population trend on the ACP is uncertain, we conclude that 
the number of breeding yellow-billed loons on the ACP breeding grounds 
is either stable or declining slightly, with point estimates from 
models controlling for confounding factors estimating decline on the 
order of ~1 percent per year. We will continue to look for ways to 
improve our ability to detect trends. Surveys in western Alaska have 
not been conducted for a long enough period (2005 and 2007) to detect 
trends.
Russia
    In Russia, recent data are fragmentary, making it difficult to 
determine trends. In the west, the Red Data Book of the Russian 
Federation (2001, p. 366) stated that the species no longer nests in 
European Russia where it was formerly found, such as the Kola 
Peninsula, the archipelago of Novaya Zemlya, and Vaigach and Ainovy 
Islands in the Kara Sea, although it is unclear how abundant or 
widespread the species was in these areas historically. (However, 
Kalyakin (2001, p. 10) reports finding it nesting on Novaya Zemlya, 
although it is ``extremely rare.'') Similarly, according to the Red 
Data Book of the Yamal-Nenets Autonomous District (1997) near the 
western end of the Russian breeding range, in the previous 20 years 
only a few non-breeding yellow-billed loons were recorded in the 
District. Strann (in litt. 2008) speculated that since the early 1990s 
there may have been a decline in the number of yellow-billed loons in 
the main Norway wintering area, which would be consistent with a 
western Russian breeding ground range contraction if birds nesting in 
western Russia migrate to Norway for winter (which seems logical). We 
were unable to find either the source of the Red Data Book statements 
or supporting evidence for this potential range contraction. In eastern 
Russia, yellow-billed loons apparently no longer nest along the 
northern coast of the Sea of Okhotsk where they occurred 30-50 years 
ago, nor on the Anadyr River delta (Red Data Book of the Russian 
Federation 2001, p. 366; Red Data Book of the Northern Far East of 
Russia 1998, p. 97). However, Solovyova (in litt. 2008) reported that 
the number of breeding yellow-billed loons may be increasing in some 
locations in eastern Siberia, specifically near Chaun Bay in western 
Chukotka, and at Belyaka Spit near Kolyuchin Bay in northeastern 
Chukotka.
    In summary, we found unsubstantiated reports that the species may 
no longer be found in parts of its historical range in Russia, but 
there is somewhat contradictory information for some areas and a lack 
of survey data for all areas. Yellow-billed loons may also be 
increasing in some areas in Russia.

[[Page 12939]]

We conclude that we do not have reliable trend information for the 
Russian breeding grounds.
Canada
    As described above for Population Size, survey data for Canadian 
breeding grounds cover a small portion of the range, and have not been 
conducted for enough years to analyze trends. We conclude that we do 
not have reliable trend information for Canadian breeding grounds.
    To summarize rangewide population trend information, we have 
reliable data indicating that the ACP breeding population is stable or 
slightly declining. We do not have reliable evidence from other 
breeding areas that breeding populations are increasing or decreasing. 
There have been no surveys of yellow-billed loons on wintering areas, 
so we have no trend information from those areas.

Population Resiliency

    Certain intrinsic aspects of yellow-billed loon ecology and 
demography, including low and variable productivity, adult survival, 
and low population numbers, are relevant to the species' status. Stable 
populations of K-selected species, such as the yellow-billed loon, are 
characterized by low annual productivity rates balanced with high 
annual survival rates, meaning that individuals must live many years to 
replace themselves with offspring that survive to recruit into the 
breeding population. Low productivity means that depleted K-selected 
species have lower recovery potential and slower recovery rates 
following population declines than r-selected species, which are 
characterized by high annual productivity. Factors that reduce 
productivity, including loss of productive breeding habitats, reduction 
in prey populations, and increases in nest predators, may further 
constrain K-selected species' recovery potential. Further, most arctic 
species are characterized by variable annual productivity, given the 
vagaries and severity of arctic weather, fluctuations in predator-prey 
relationships, and other aspects of arctic ecology. The population 
impact of threats that reduce productivity could be magnified if 
coincident with an infrequent year of otherwise high productivity.
    Although factors that compromise productivity can cause populations 
to decline, adult survival is likely the more important determinant of 
K-selected species' population size and persistence (Smith and Smith 
2001, p. 235). If enough adults are removed from the population prior 
to replacing themselves (i.e., adult survival is decreased), the 
population will decline. Perhaps most pertinent to a discussion of 
extinction, rare species--those with low numbers--are intrinsically 
closer to a threshold below which recovery is not possible (i.e., 
minimum viable population) (Hunter 1996, p. 137).
    These intrinsic aspects of yellow-billed loon ecology and 
demography signal the continuing need to monitor yellow-billed loon 
populations, despite the fact that the species continues to be widely 
distributed across both its arctic breeding range, which is nearly 
holarctic, and in its wintering range.

Factors Affecting the Yellow-Billed Loon

    Section 4(a)(1) of the Act (16 U.S.C. 1533(a)(1)) and regulations 
promulgated to implement the listing provisions of the Act (50 CFR part 
424) set forth the procedures for adding species to the Federal Lists 
of Endangered and Threatened Wildlife and Plants. A species may be 
determined to be an endangered or threatened species due to one or more 
of the five factors described in section 4(a)(1) of the Act. Below, we 
provide a summary of our analysis of threats to the yellow-billed loon.

Factor A: Present or Threatened Destruction, Modification, or 
Curtailment of the Habitat or Range

    We considered whether yellow-billed loon habitats are threatened by 
oil and gas development (including disturbance, changes in freshwater 
chemistry and pollutant loads, and changes in freshwater hydrology), by 
degradation of the marine environment from pollution or overfishing, or 
by climate change. Potential threats from oil and gas development are 
addressed by the petitioners under Factor E, but are discussed here 
under Factor A because they are potential mechanisms for rendering 
breeding habitats unsuitable. Potential direct impacts on loon 
mortality associated with development, such as increased predation and 
oil spills, are discussed under Factors C and E, respectively.
Terrestrial Oil and Gas Development
    Terrestrial and marine oil and gas development occurs in the range 
of the yellow-billed loon. Here we discuss terrestrial development in 
Alaskan and Russian breeding grounds. We are not aware of any 
terrestrial oil or gas development within the breeding range of the 
yellow-billed loon in Canada; planned terrestrial development on the 
Mackenzie River Delta is outside the breeding range, although activity 
there could affect loons migrating through adjacent marine waters. 
Marine activities related to oil and gas development are discussed 
under Factor E.
    Much of the yellow-billed loon's breeding habitat in Alaska is 
within areas available for oil and gas leasing and development. 
Approximately three-quarters of the yellow-billed loons that nest in 
Alaska, and over 90 percent of those that nest on Alaska's ACP, occur 
within the 9.5-million-ha (23.5-million-ac) NPR-A (Earnst et al. 2005, 
p. 300), in areas that are leased or available for leasing for oil and 
gas exploration and development. Approximately 29 percent of yellow-
billed loons breeding on the ACP nest in NPR-A tracts that have been 
leased (Stehn and Platte, U.S. Fish and Wildlife Service, in litt. 
2008, p. 1), and 25 exploration wells were drilled during the period 
2000-2007 (https://www.blm.gov/ak/st/en/prog/energy/oil_gas/npra.html, 
accessed 3 June 2008). The Northwest Planning Area (NW) NPR-A 
Integrated Activity Plan/Environmental Impact Statement Record of 
Decision (ROD) (USDOI-BLM 2004a, p. 5) has made 100 percent of the NW 
NPR-A available for leasing. The Final NE NPR-A Supplemental Integrated 
Activity Plan/Environmental Impact Statement ROD (USDOI-BLM 2008b, p. 
1) allows leasing of 86 percent (1.6 million ha, or 3.94 million ac) of 
the NE NPR-A immediately, and an additional 9 percent beginning in 
2018. Virtually all yellow-billed loon breeding habitat in the NE NPR-A 
is within areas currently available for leasing (USDOI-BLM 2008a, 
Volume 6, Maps 2-4 and 3-10).
    If offshore development occurs in the Chukchi Sea, it is 
anticipated that a 500-km (300-mi) oil pipeline will be built across 
the NPR-A from the coast between Icy Cape and Point Belcher to the 
Trans-Alaska Pipeline (USMMS 2008, p. IV-10). The State of Alaska also 
leases rights to oil and gas development on its land, including the 
Colville River Delta (ADNR 2008, p. 1), where development has already 
occurred within the range and habitats of the yellow-billed loon (ADNR 
2008, p.1). Thus, as a result of past and possible future oil and gas 
lease sales, and ongoing exploratory efforts, a significant portion of 
the yellow-billed loon's breeding habitat in NPR-A is subject to 
potential oil and gas development. Additionally, resource development 
in adjacent offshore areas may result in the construction of pipelines 
across breeding habitat in NPR-A.
    Although lease sales and exploratory efforts set the stage for 
possible future development in yellow-billed loon breeding habitat in 
northern Alaska,

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determining the likelihood and timing of eventual development is 
difficult. In northeast NPR-A, several satellite production pads 
associated with existing infrastructure and facilities outside NPR-A at 
the Alpine field on the Colville River delta are in various stages of 
planning, permitting, and construction. It is very likely that within 
the next 10 to 20 years at least 5 to 7 satellite production pads 
feeding the existing central processing facility will be in operation, 
with some pads on State lands on the delta and some on adjacent Federal 
lands in NPR-A. Elsewhere in NPR-A the likelihood and timing of 
possible future development are more difficult to predict. BLM 
estimates that exploratory activities take roughly 10 years before 
construction begins (USDOI-BLM 2008c, p. 13), with roughly 70 years 
from the initiation of exploration until final field abandonment. 
Initial exploratory activities have commenced in some areas in NPR-A; 
exploration has yet to begin on some existing leased tracts elsewhere; 
and other lands have not yet been leased or offered for lease. Thus, 
yellow-billed loon habitat in the Colville River delta and adjacent 
NPR-A varies in its potential for future oil and gas development, and 
the timing of development, where it occurs, will be staggered starting 
with imminent development on and near the Colville River delta, 
followed by exploration, construction, and production over a period of 
several decades elsewhere, persisting for at least 70 years and 
possibly longer in various areas.
    Terrestrial oil development is ongoing, and likely to increase, at 
the western edge of Russian yellow-billed loon breeding range. These 
areas have never been systematically surveyed for loons, so the 
historical occurrence and degree to which development areas overlaps 
areas used by loons is unknown. On the Yamal Peninsula, the largest gas 
field is the Bovanenkovskeo field, which is projected, beginning in 
2011, to produce approximately 115 billion cubic meters (4 trillion 
cubic ft) of gas, which will be transported by new railways and a 
2,451-km (1,523-mi) long pipeline currently under construction (Barents 
Observer 2008, p. 1). A liquefied-natural-gas plant is planned on the 
Kara Sea coast of the peninsula. The Yuzhnoe-Khykchuyu oil field in the 
Timan-Pechora province near the port of Varandey on the Pechora Sea is 
among the largest in Russia, and is planned as an anchor field for 
further development (ConocoPhillips 2008, p. 1). Major western Siberian 
oil fields in the Pechora River basin of the Komi Republic have 
operated for decades upstream of yellow-billed loon breeding range, and 
a large mining industry operates out of Norilsk on the Taymyr 
Peninsula. Gazprom, Russia's largest oil and gas company, is developing 
new discoveries in Chukotka near Anadyr (Gazprom Neft 2004, p. 1). In 
addition to these activities at the western edge of the Russian 
breeding area, reserves exist but are not currently planned for 
development in the Laptev formation on the arctic coast east of the 
Lena River (USGS 2007, pp. 1-2).
    We are not aware of any yellow-billed loon surveys in the Taymyr, 
Timan-Pechora, and Yamal districts described above; so we do not know 
whether or to what extent yellow-billed loon breeding habitat overlaps 
with zones of industrial activity in this area. It is possible that the 
reported potential contraction at the western edge of the yellow-billed 
loon's range in Russia (Red Data Book of the Russian Federation 2001, 
p. 366) could have resulted from the effects of resource extraction in 
the region, but we have no evidence for or