[Federal Register Volume 78, Number 192 (Thursday, October 3, 2013)]
[Proposed Rules]
[Pages 61764-61801]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-24172]



[[Page 61763]]

Vol. 78

Thursday,

No. 192

October 3, 2013

Part IX





Department of the Interior





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Fish and Wildlife Service





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50 CFR Part 17





Endangered and Threatened Wildlife and Plants; 12-Month Finding on a 
Petition To List Kittlitz's Murrelet as an Endangered or Threatened 
Species; Proposed Rule

  Federal Register / Vol. 78 , No. 192 / Thursday, October 3, 2013 / 
Proposed Rules  

[[Page 61764]]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R7-ES-2013-0099; 4500030113]


Endangered and Threatened Wildlife and Plants; 12-Month Finding 
on a Petition To List Kittlitz's Murrelet as an Endangered or 
Threatened Species

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 Kittlitz's murrelet 
(Brachyramphus brevirostris) as an endangered or threatened species and 
to designate critical habitat under the Endangered Species Act of 1973, 
as amended (Act). After a review of the best available scientific and 
commercial information, we find that listing the Kittlitz's murrelet is 
not warranted at this time. However, we ask the public to submit to us 
any new information that becomes available concerning threats to the 
Kittlitz's murrelet or its habitat at any time.

DATES: The finding announced in this document was made on October 3, 
2013.

ADDRESSES: This finding is available on the Internet at http://www.regulations.gov at Docket Number FWS-R7-ES-2013-0099. 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, Juneau Fish and Wildlife Field Office, 3000 
Vintage Blvd., Suite 201, Juneau, AK 99801. Please submit any new 
information, materials, comments, or questions concerning this finding 
to the above street address.

FOR FURTHER INFORMATION CONTACT: Bill Hanson, Field Supervisor, Juneau 
Fish and Wildlife Field Office (see ADDRESSES); by telephone at 907-
780-1160; or by facsimile at 907-586-7099 mailto:. 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 Act (16 U.S.C. 1531 et seq.), requires 
that, for any petition to revise the Federal Lists of Endangered and 
Threatened Wildlife and Plants that contains substantial scientific or 
commercial information that listing the species may be warranted, we 
make a finding within 12 months of the date of receipt of the petition. 
In this finding, we will determine that the petitioned action is: (1) 
Not warranted, (2) warranted, or (3) warranted, but the immediate 
proposal of a regulation implementing the petitioned action is 
precluded by other pending proposals to determine whether species are 
endangered or threatened, and expeditious progress is being made to add 
or remove qualified species from the Federal Lists of Endangered and 
Threatened Wildlife and Plants. Section 4(b)(3)(C) of the Act requires 
that we treat a petition for which the requested action is found to be 
warranted but precluded as though resubmitted on the date of such 
finding, that is, requiring a subsequent finding to be made within 12 
months. We must publish these 12-month findings in the Federal 
Register.

Previous Federal Actions

    We received a petition dated May 9, 2001, from the Center for 
Biological Diversity, Coastal Coalition, Eyak Preservation Council, 
Lynn Canal Conservation, Inc., and Sitka Conservation Society, 
requesting that the Kittlitz's murrelet be listed as an endangered or 
threatened species and critical habitat be designated. Included in the 
petition was supporting information regarding the species' taxonomy and 
ecology, historical and current distribution, status, and potential 
causes of decline. We acknowledged receipt of the petition in a letter 
to the Center for Biological Diversity, dated June 7, 2001. In that 
letter we stated that, due to funding constraints in Fiscal Year 2001, 
we would not be able to begin processing the petition at that time, but 
would request the appropriate funding for Fiscal Year 2002. We also 
stated that emergency listing of the Kittlitz's murelet was not 
warranted at that time.
    On June 13, 2002, we received a 60-day notice of intent to sue from 
the Center for Biological Diversity alleging a violation of section 4 
of the Act for failure to complete 90-day and 12-month findings on the 
petition.
    On May 4, 2004, we published a candidate notice of review (CNOR) in 
the Federal Register (69 FR 24876) in which the Kittlitz's murrelet was 
included in the Summary of New Candidates. In this document, we 
indicated that listing of the Kittlitz's murrelet under the Act was 
warranted but precluded rangewide, and we assigned a listing priority 
number (LPN) of 5 to this species. The LPN of 5 reflected non-imminent 
threats of high magnitude for this species. On May 11, 2005 (70 FR 
24870) and September 12, 2006 (71 FR 53756), we retained Kittlitz's 
murrelet in our CNORs with a LPN of 5.
    On December 6, 2007, we published an annual CNOR in the Federal 
Register (72 FR 69034) that included a notice of change in LPN for the 
Kittlitz's murrelet, elevating it from a 5 to a 2 to acknowledge that 
threats facing this species were of high magnitude and imminent. The 
CNORs in 2008 (73 FR 75176, December 10, 2008), 2009 (74 FR 57804, 
November 9, 2009), and 2010 (75 FR 69222, November 10, 2010) continued 
to assign a LPN of 2 to Kittlitz's murrelet.
    On July 12, 2011, the Service reached a multi-district litigation 
settlement agreement with the Center for Biological Diversity that 
requires the Service to review and address the needs of over 250 
species, including the Kittlitz's murrelet, included in a CNOR 
published in the Federal Register on November 10, 2010 (75 FR 69222). 
The Kittlitz's murrelet was included in the settlement, requiring the 
Service to submit a proposed rule or not-warranted finding to the 
Federal Register by September 30, 2013.
    On October 26, 2011, the CNOR (76 FR 66370) included a notice of 
change in listing priority for the Kittlitz's murrelet, downgrading the 
LPN from a 2 to an 8 because we determined through a reassessment of 
the threats that their magnitude was moderate (not high) and threats 
were imminent.
    In Fiscal Year 2012, the Service initiated work on the listing 
evaluation of the Kittlitz's murrelet, as stated in the November 21, 
2012 CNOR (77 FR 69994).
    This document addresses our requirements under the multi-district 
litigation settlement agreement.

Species Information

    This document constitutes a 12-month finding on the May 9, 2001 
petition to list the Kittlitz's murrelet as an endangered or threatened 
species.
    The petitioners requested the Kittlitz's murrelet be listed as an 
endangered or threatened species and we confirm that this species is a 
listable entity under the Act. Because we find that listing the 
Kittlitz's murrelet rangewide is not warranted, as explained below in 
the Finding section, we conducted further analysis to evaluate any 
potential distinct population segments (DPS) or significant portion(s) 
of the range (SPR) within the range of the Kittlitz's murrelet exist 
that may require listing. However, we did not identify any

[[Page 61765]]

populations of the Kittlitz's murrelet that meet the definition of DPS 
or SPR (see appropriate sections below).
Taxonomy and Species Description
    Kittlitz's murrelet (Brachyramphus brevirostris; Vigors 1829) is a 
member of the Alcidae or auk family. Brachyramphus murrelets are 
unusual because unlike the rest of this diverse family of seabirds that 
nest in colonies, they nest solitarily. There are two additional 
species within the genus, the marbled murrelet (B. marmoratus; Gmelin 
1789) and the long-billed murrelet (B. perdix; Pallas 1811; Friesen et 
al. 1996a, p. 360). The distributions of marbled murrelet and 
Kittlitz's murrelet overlap in Alaska and the distribution of the long-
billed murrelet overlaps with the Kittlitz's murrelet in portions of 
eastern Russia (Friesen et al. 1996b, p. 682). All three species 
generally are similar in appearance, but physical and genetic 
differences among them are well documented (Pitocchelli et al. 1995, 
pp. 239-248; Friesen et al. 1996a, pp. 363-365; Friesen et al. 1996b, 
pp. 681, 685-687; Day et al. 1999, p. 2). Kittlitz's murrelets are 
heavier (8.3 ounces [oz] (236 grams [g])) (Kissling, Service, 2007-
2012, unpublished data), and have larger heads, longer wings and tails, 
and smaller bills than do marbled murrelets (7.7 oz [219 g]) 
(Pitocchelli et al. 1995, pp. 241-245; Kuletz et al. 2008, pp. 91-95; 
Kissling, unpublished data). Long-billed murrelets are distinctly 
larger than both Kittlitz's and marbled murrelets, have a longer bill 
than them, and have a white eye ring (Friesen et al. 1996b, p. 681).
    Mitochondrial DNA (mtDNA) sequences and restriction fragment 
analysis show significant differentiation among the three species 
(Pitocchelli et al. 1995, pp. 244-247; Friesen et al. 1996a, pp. 364-
366; Friesen et al. 1996b, pp. 683-687). Analysis of allozymes further 
strengthens the evidence that these murrelets are separate species 
(Friesen et al. 1996a, pp. 361-365). In addition, nuclear introns and 
cytochrome b gene sequencing showed no evidence of recent hybridization 
between marbled and Kittlitz's murrelets (Pacheco et al. 2002, pp. 179-
180).
    The Kittlitz's murrelet has been considered a single panmictic 
population (with random mating of individuals within a breeding 
population) for lack of any evidence to suggest otherwise, but several 
recent studies suggest that there is strong population genetic 
structure in this species (MacKinnon 2005, pp. 18, 24-25; Birt et al. 
2011, pp. 47-49; Friesen and Birt 2012, pp. 6-9). Intra-specific 
analyses of genetic data (allozymes, cytochrome b gene, control region 
of mtDNA, and nuclear DNA) indicate that there are two strongly 
differentiated genetic groups: one in the western Aleutian Islands and 
the other in the Gulf of Alaska (Friesen et al. 1996b, p. 686; 
MacKinnon 2005, pp. 18, 24-25; Birt et al. 2011, pp. 47-49; Friesen and 
Birt 2012, pp. 6-9). Birt et al. (2011, pp. 46, 49) concluded that gene 
flow between these two groups has been very limited for an extended 
period of time and that the genetic structure probably is due to 
historical fragmentation of populations; however, this study was based 
on limited sample sizes within and among populations of Kittlitz's 
murrelet (53 individuals from three study sites; n=15 from Attu, n=18 
from Kachemak Bay, n=20 from Glacier Bay).
    Friesen and Birt (2012, pp. 9, 16) expanded the study to include 
301 individuals from nine study sites in coastal Alaska ranging from 
Glacier Bay in the south to Barrow in the north; results supported the 
previous findings of strong genetic structure in the Kittlitz's 
murrelet, resulting in an eastern group (Glacier Bay to Kodiak Island) 
and a western one (Adak, Agattu and Attu islands) that probably 
diverged from one another a long time ago (547,428 years ago; 95 
percent confidence interval [CI]=131,000 to 896,000; confidence 
intervals are a range of values defined so that there is a specified 
probability that the value of a parameter lies within it) (Friesen 
2013, in litt.). In addition, there are two contact zones where 
Kittlitz's murrelets have mixed ancestry from both groups; those 
contact zones are located between Atka and Unalaska islands in the 
eastern and central Aleutian Islands and in northern Alaska, although 
the sample size from this latter area was small (n=9) (Friesen and Birt 
2012, pp. 10, 16).
    Importantly, results from the expanded genetic study suggest that 
there are low levels of contemporary movement between the two groups 
and that Kittlitz's murrelets from the two groups can and do interbreed 
and that offspring are viable and fertile (Friesen and Birt 2012, p. 
10). Therefore, birds within the two groupings (eastern and western) do 
not constitute separate species because genetic connectivity still 
exists (Friesen and Birt 2012, p. 10). Further, although a 
comprehensive, comparative study has not occurred yet, there are no 
documented differences in morphology (e.g., plumage, size) or behavior 
of Kittlitz's murrelets from the eastern and western genetic groups or 
across their range (Day et al. 1999, pp. 2, 20; Day 2013, in litt.). 
Both groups have sufficient levels of intra-specific genetic variation 
and do not have evidence of a genetic bottleneck (Friesen and Birt 
2012, pp. 17-18; Kissling 2012, in litt.). To date, there have been no 
genetic analyses comparing Kittlitz's murrelets from Russia with those 
from North America (preliminary laboratory work has been initiated but 
was not completed at the time of writing of this finding). We recognize 
the two genetic groupings (eastern and western), but do not consider 
these groups to meet the definition of a DPS (see below).
Distribution
    The range of the Kittlitz's murrelet encompasses a vast area from 
the Russian Far East (northern Okhotsk Sea, Bering Sea coast, and coast 
of the Chukchi Sea in northern Chukotka as far to the northwest as Cape 
Schmidt) across to the Aleutian Islands and southeastern Alaska, and 
north to northwestern Alaska (Day et al. 1999, pp. 3-6; Artukhin et al. 
2011, p. 29). Nests have been recorded throughout nearly the entire at-
sea range. Seasonal shifts in distribution are discussed below. There 
is no reliable information to suggest that the historical range of the 
Kittlitz's murrelet is substantially different than the current range.
Habitat and Life History
    In this section, we describe seasonal shifts in distribution and 
habitats used, molting cycles, foraging and nesting characteristics, 
and the demography of the Kittlitz's murrelet.
    The Kittlitz's murrelet typically spends its entire annual cycle in 
marine waters within and adjacent to Alaska and eastern Russia, 
generally moving offshore (maximum observed 106 miles [mi] (170 
kilometers [km]) from shore) during the non-breeding months (August-
March or April) and nearshore (within 3.4 mi [5.5 km] from shore) 
during the breeding season (April-August) with some latitudinal 
variation. Low numbers of adult Kittlitz's murrelets also have been 
observed during the breeding season on freshwater lakes (Savage 2013, 
in litt.; Walsh 2013, in litt.). The seasonal appearance, increase, and 
disappearance of Kittlitz's murrelets during systematic surveys at sea 
during the breeding season (Klosiewski and Laing 1994, pp. 55, 83; 
Kendall and Agler 1998, p. 55; Kuletz et al. 2003a, pp. 17-20; Robards 
et al. 2003, pp. 92, 100, 104; Kissling et al. 2007, pp. 2167-2168; 
Kuletz et al. 2008, pp. 21-22, 53-54) demonstrate that murrelets move 
inshore near to known breeding areas in south-coastal Alaska beginning 
in March or April, peak in densities in late

[[Page 61766]]

June and early July, and leave these areas rapidly, but asynchronously 
in late July to mid August. Post-breeding movements of murrelets in 
late July and August are westward to nearshore waters of Kodiak Island 
and along the Alaska Peninsula and Bristol Bay, then northward to the 
Bering and Chukchi seas and even extending, in a few cases, into the 
Beaufort Sea, where birds may remain until about late October when 
their pre-basic molt is complete (Day et al. 2011, pp. 57-59; Madison 
et al. 2012, p. 1). At-sea surveys have documented the regular 
occurrence of Kittlitz's murrelets from August through October in 
offshore waters between Cape Peirce and north of Nunivak Island, and 
north of the Bering Strait from Cape Lisburne to the western Beaufort 
Sea (Kuletz, Service, 2006-2012, unpublished data). In November, as sea 
ice builds in the Chukchi and Beaufort seas, Kittlitz's murrelets begin 
to move south into the Bering Sea where they probably winter until late 
February or early March (Day et al. 1999, p. 7; Kuletz and Lang 2010, 
pp. 39-43; Day et al. 2011, p. 59). However, records of winter 
sightings in southeastern, south-central, and western Alaska 
(Klosiewski and Laing 1994, p. 83; Kendall and Agler 1998, pp. 55-56; 
Day et al. 1999, pp. 4-5; Day 2006, pp. 208-209; Stenhouse et al. 2008, 
p. 61) indicate that some individuals are year-round residents in these 
areas. Annual movements of Kittlitz's murrelets in eastern Russia, the 
Aleutian Islands, and northern Alaska remain poorly known, although 
limited satellite-tag data indicate that Kittlitz's murrelets in the 
central Aleutians follow the same northward post-breeding migration to 
the Bering and Chukchi seas as those birds tagged in the Gulf of Alaska 
do (Madison et al. 2012, p. 1).
    The winter range of the Kittlitz's murrelet is poorly known (Day et 
al. 1999, pp. 4-5). Recent information from icebreaker-based at-sea 
surveys indicates that open water leads (fractures in sea ice caused by 
wind drift or ocean currents) and polynyas (a large area of open water 
surrounded by sea ice), primarily south of St. Lawrence Island, between 
Nunivak and St. Matthew islands, and east of the Pribilof Islands, may 
be important wintering areas (Kuletz and Lang 2010, pp. 40-43; Kuletz, 
unpublished data). Most Kittlitz's murrelets encountered during early 
spring surveys in the sea ice were in pairs (Kuletz and Lang 2010, p. 
40). The exact winter distribution of Kittlitz's murrelets in the 
Bering Sea probably shifts with respect to dynamic changes in open 
leads and polynyas (Kuletz, unpublished data), which tend to form 
consistently near the large Bering Sea islands and some coastal areas 
(Niebauer et al. 1999, p. 34). The winter range of the species in 
eastern Russia is largely unknown, but observations have been reported 
from the Kamchatka Peninsula and the Kuril Islands in the Russian Far 
East south to northern Japan (Flint et al. 1984, pp. 156-157; Brazil 
1991, p. 164; but see Carter et al. 2011, p. 8). A few birds also have 
been observed during late winter in the Sireniki polynya of southern 
Chukotka and the western Bering Sea in Russia (Konyukhov et al. 1998, 
p. 325; Shuntov 2000, pp. 97-98).
    During the summer breeding season, Kittlitz's murrelets usually, 
but not exclusively, are associated with glacially influenced waters, 
especially those with floating ice, in south-coastal Alaska, where 
large numbers aggregate (Isleib and Kessel 1973, p. 100; Kendall and 
Agler 1998, p. 58; Day et al. 2000, p. 109; Arimitsu et al. 2011, p. 
18; Hoekman et al. 2011, p. 40; Kissling et al. 2011, p. 7; Kuletz et 
al. 2011a, pp. 102-103; Kuletz et al. 2011b, pp. 90-92; Piatt et al. 
2011, p. 70; Arimitsu et al. 2012, p. 18). The exact reasons for this 
association are unclear, but hypothetical explanations exist. This 
pattern of at-sea distribution simply may reflect an adaptation for 
nesting on unvegetated scree slopes or nunataks (isolated peaks of rock 
projecting above the surface of inland snow or ice) often associated 
with tidewater glaciers, which are selected because these areas are 
thought to be predator-free (Piatt et al. 1999, p. 12; Kissling et al. 
2012, p. 1; Lawonn 2012, pp. 21, 94-95). Their association with 
tidewater glaciers also may reflect foraging preference and efficiency 
in glacial-affected water (Day et al. 2003, pp. 681, 686; Kuletz et al. 
2003b, p. 138; Allyn et al. 2012, pp. 244-245; Arimitsu et al. 2012, 
pp. 14, 18). In addition, strong nest area and site fidelity may cause 
these birds to return to the same area (Piatt et al. 1999, p. 11; Kaler 
et al. 2010, p. 18; Lawonn 2012, pp. 82, 88; Kenney and Kaler 2013, p. 
73; Kissling, unpublished data), but it is unknown if the same birds 
are using a particular area annually or if site characteristics make 
the area suitable to breeding pairs.
    The Kittlitz's murrelet has two distinct plumages in its annual 
cycle and therefore undergoes two molts per year: a full, pre-basic 
molt in fall (September-October) and a partial, pre-alternate molt in 
spring (April-May) (Day et al. 1999, pp. 18-19). During the pre-basic 
molt, individuals transition from their mottled, cryptic plumage of the 
breeding season to the sharply contrasting black and white plumage of 
the non-breeding season. The pre-basic molt replaces of the wing, tail, 
and body feathers, whereas the pre-alternate molt replaces only the 
body feathers. Although Sealy (1977, p. 467) reported that in the pre-
basic molt wing feathers grow synchronously rendering a flightless 
period (2-4 weeks) for the bird, Pyle (2009, p. 222) found that 
Kittlitz's murrelets undergo a non-synchronous molt, either 
sequentially or in blocks, perhaps to avoid an extended flightless 
period, and probably prolonging the pre-basic molt period.

Foraging

    Because little research on the Kittlitz's murrelet has occurred 
during the winter, information about foraging and other life-history 
characteristics are based primarily on observations made during the 
spring, summer, and fall. Kittlitz's murrelets tend to forage as single 
birds or in small groups, but seldom in mixed-species feeding flocks 
(Day and Nigro 2000, pp. 8-10, 12). Most foraging occurs during the day 
(Day et al. 1999, p. 9; Madison et al. 2010, p. 1), especially in the 
morning (Day and Nigro 2000, p. 5). They pursue and capture prey 
underwater by using wing-propelled ``flight'' and consume prey either 
at the surface or underwater (Day et al. 1999, p. 9; Day and Nigro 
2000, p. 9).
    The Kittlitz's murrelet appears to be a flexible forager with a 
diet that varies considerably among seasons but is fairly specialized 
within a season (Hatch 2011, pp. 25-26, 35; Allyn 2012, p. 102). 
Although Kittlitz's murrelets are considered to be piscivorous, they 
also eat zooplankton throughout the entire annual cycle (Day et al. 
1999, p. 9), more so than for the closely related marbled murrelet 
(Hobson et al. 1994, p. 795; but see Day et al. 1999, p. 10). In the 
pre-breeding season, Kittlitz's murrelets feed on low-trophic-level 
prey such as macrozooplankton and larval fishes and gradually 
transition to consuming larger proportions of higher-trophic-level prey 
(planktivorous fishes) as the breeding season commences (Hatch 2011, 
pp. 24-25; Allyn 2012, p. 102). During the breeding season, Kittlitz's 
murrelets feed on a combination of macrozooplankton (36-44 percent of 
their diet) and schooling fishes such as Pacific capelin (Mallotus 
villosus), Pacific sand lance (Ammodytes hexapterus), juvenile Pacific 
herring (Clupea pallasi), and juvenile walleye pollock (Theragra 
chalcogramma) (Sanger 1983, p. 692; Hobson et al. 1994, p. 795; Day et 
al. 1999, p. 9; Day and Nigro 2000, pp. 11-13; Kuletz et al. 2003a, pp. 
23, 28; Agness 2006, p. 119; Kuletz et al. 2008, p. 26; Hatch 2011, p. 
47; Kaler et al.

[[Page 61767]]

2011, p. 15; Allyn 2012, p. 102; Lawonn 2012, pp. 27-28). By the post-
breeding period they feed almost exclusively on these high-lipid fish, 
consuming only small proportions (4-9 percent) of zooplankton (Hatch 
2011, p. 47; Allyn 2012, pp. 100-101). In the northern Bering and 
Chukchi seas, a variety of small arctic fishes and large zooplankton 
are abundant (Eisner et al. 2013, pp. 97-102) and presumably are 
consumed by Kittlitz's murrelets in the fall and winter. Based on a 
comparison of stable isotopes (carbon and nitrogen) from recently 
captured murrelets and museum specimens, these seasonal foraging 
patterns have been consistent over the past century (1911-2009) (Hatch 
2011, p. 27).
    During nesting, Kittlitz's murrelets carry a single whole fish at a 
time to their chick. Adult fish-holding murrelets often stage on the 
water before returning to their nest to deliver the fish to the chick; 
therefore, chick diet has been inferred by identifying these fishes 
held in the bill of adults on the water and by directly monitoring food 
deliveries to chicks at nest sites. The proportion of fish held in bill 
by adults on the water that is identified to species is low (21-23 
percent) (Agness 2006, p. 116; Kuletz et al. 2008, p. 26) because of 
the difficulty for the observer to do so at a distance and under at-sea 
conditions. This method is useful, however, in areas where it is 
difficult to monitor nests directly such as in glacial-dominated 
landscapes, where Kittlitz's murrelets have been observed on the water 
holding primarily sand lance and capelin, and to a lesser extent 
Pacific herring and Pacific salmon (Oncorhynchus spp.) (Agness 2006, p. 
124; Kuletz et al. 2008, p. 26). In contrast to the low identification 
rate of fish held by murrelets on the water, most fish (70-85 percent) 
delivered to chicks at monitored nests have been identified to species 
(Naslund et al. 1994, p. 46; Lawonn 2012, p. 27-28; Kaler 2012, in 
litt.; Kissling, unpublished data). Pacific sand lance is the fish 
species delivered most commonly to chicks (57 percent of identified 
deliveries) and occurs in chick diet in all areas where nests have been 
monitored (n=33 nests; western Aleutians and Kodiak islands and 
Kachemak and Icy bays) (Naslund et al. 1994, p. 46; Lawonn 2011, pp. 
27-28; Kaler 2012, in litt.; Kissling, unpublished data). Although 
significant geographic variation exists (see Nesting, below), the 
remainder of chick diet is composed of hexagrammids (23 percent; kelp 
greenling [Hexagrammos decagrammus] and Atka mackerel [Pleurogrammus 
monopterygius]), capelin (10 percent), gadids (5 percent; Pacific cod 
[Gadus macrocephalus]) and rockfish (Sebastes spp.), smelt (2 percent; 
Osmeridae family) and Pacific herring (1 percent) (Naslund et al. 1994, 
p. 46; Lawonn 2011, pp. 27-28; Kaler 2012, in litt.; Kissling, 
unpublished data). In both methods used to determine chick diet, it is 
not known if there is bias associated with fish identification due to 
size of the prey item, but this is certainly possible.
    Small schooling fishes that are oily, such as sand lance and 
capelin, are thought to be favored for chick meals because of their 
high lipid, and therefore energy, content (van Pelt et al. 1997, p. 
1395; Anthony et al. 2000, p. 75; Litzow et al. 2004, p. 1150). 
Capelin, in particular, is hypothesized to be an important prey species 
for Kittlitz's murrelets in glacially-affected waters because this fish 
species occurs in cold, turbid marine waters close to tidewater 
glaciers (Arimitsu et al. 2008, p. 137). Chicks eating oily fishes 
receive more calories and grow faster (Ostrand et al. 2004, p. 69), 
resulting in fewer foraging trips for parents, when high-energy fishes 
are fed to chicks than when lower-energy fishes such as walleye pollock 
or rockfishes, are fed to chicks (Hatch 2011, pp. 74-77, 103-104). 
Therefore, a change in the availability of high-energy forage fishes 
during the breeding season could affect the reproductive success of 
Kittlitz's murrelets (van Pelt et al. 1997, p. 1393; Anderson and Piatt 
1999, p. 117; Becker et al. 2007, pp. 276-278; [Ouml]sterblom et al. 
2008, pp. 967-974).
    Several studies have described marine habitat use of Kittlitz's 
murrelets in the breeding season by associating murrelet distribution 
with marine biotic and abiotic factors in areas where glaciers exist 
(Day and Nigro 2000, pp. 8-9; Day et al. 2003, pp. 685-694; Kissling et 
al. 2007, p. 2168; Kuletz et al. 2008, p. 24-27; Allyn et al. 2012, pp. 
240-242; Arimitsu et al. 2012; pp. 12-14; Renner et al. 2012, pp. 2035-
2039). Generally, Kittlitz's murrelets prefer to forage in shallow 
(less than 196 feet [ft] (60 meters [m])), glacially affected waters 
(Kuletz et al. 2008, p. 37) often with some floating ice (Day and Nigro 
2000, pp. 6, 8; Day et al. 2003, pp. 686, 694; Kuletz et al. 2003b, pp. 
136, 139), but it is not known whether ice occurrence is biologically 
meaningful to murrelets. Arimitsu et al. (2012, p. 18) postulated that 
the presence of ice may instead serve as a proxy to other factor(s), 
such as outflow of sediment-laden freshwater from glacial streams and a 
downstream increase in the availability of certain near-surface prey 
(e.g., euphausiids). Kuletz et al. (2003b, p. 139) hypothesized that 
the undersides of icebergs and pack ice may increase prey abundance and 
availability to murrelets, perhaps due to the presence of sea ice algae 
and its role in primary production (Grebmeier et al. 2006, p. 339). 
Other studies have positively associated Kittlitz's murrelets with 
highly turbid waters (Day et al. 2003, p. 685; Renner et al. 2012, pp. 
2038-2039), often with a clear, cold freshwater lens at the surface 
less than 32 ft (10 m) in depth (Kuletz et al. 2008, p. 37; Allyn et 
al. 2012, p. 233); in fact, Day et al. (2003, p. 695) suggest that the 
eyes of Kittlitz's murrelets are large to increase their ability to 
forage in highly turbid water. This species prefers marine waters with 
sea surface temperatures of 37-48 degrees Fahrenheit (F) (3-6 degrees 
Celsius) (Day et al. 2003, p. 685; Day et al. 2011, p. 59; Allyn et al. 
2012, p. 242). Kittlitz's murrelets are often associated with areas of 
localized upwelling that are generally created by the interaction of 
landscape features, such as submerged marine sills, shoreline, hanging 
and tidewater glaciers, and strong tidal currents (Day and Nigro 2000, 
p. 5; Kuletz et al. 2003b, p. 139; Kissling et al. 2007, p. 2171; Allyn 
et al. 2012, pp. 244-245; Arimitsu et al. 2012, p. 10), but not tidal 
height (Allyn 2012, p. 101). It is not known to what extent the 
distribution of Kittlitz's murrelet depends on these marine habitat 
conditions for foraging efficiency or prey availability in a given 
year. However, it is logical to assume that daily, weekly, monthly and 
annual variability in Kittlitz's murrelet population density at a 
location may be due, at least in part, to corresponding variability in 
prey abundance.
    Kittlitz's murrelets probably switch among prey types between 
seasons or years depending on availability, as do marbled murrelets 
(Ostrand et al. 2004, p. 73; Becker et al. 2007, p. 274). High-lipid 
forage fishes are expected to represent higher-quality prey for 
seabirds than are zooplankton because the fishes' larger size should 
result in more energy gained per unit of effort spent foraging (Norris 
et al. 2007, p. 876), although macrozooplankton are not necessarily of 
lower caloric value than fishes (Vermeer and Cullen 1982, p. 35; Davis 
et al. 1998, p. 151; Hedd et al. 2002, pp. 229-230). Janssen et al. 
(2009, p. 36) reported that in some years female marbled murrelets 
producing eggs early in the breeding period had a higher proportion of 
low-trophic-level prey in the pre-breeding diet than did murrelets not 
producing eggs, signifying that low-trophic-level prey may not

[[Page 61768]]

necessarily equate to low-quality prey. Thus, the substantial amount of 
marine invertebrates in the Kittlitz's murrelet diet coupled with their 
prey-switching abilities, may buffer self-feeding adults from annual 
and seasonal variation in the availability or quality of high-energy 
forage fishes (Anderson and Piatt 1999, p. 117; Robards et al. 2003, p. 
2; Litzow et al. 2004, p. 1149; Arimitsu 2009, pp. 33-36, 45).

Nesting

    The Kittlitz's murrelet is a dispersed-nesting seabird (i.e., does 
not nest in colonies like most marine foragers) that often nests in 
remote, rugged areas and therefore little information on their nesting 
ecology existed until recently. Until 1999, only 19 confirmed 
Kittlitz's murrelet nests had been described, 17 in Alaska and 2 in 
Russia (Day et al. 1999, pp. 25-26). In 2005, a nest was 
opportunistically discovered on Agattu Island, at the western end of 
the Aleutian Islands (Kaler 2006, p. 3). Since that time, a number of 
different studies have been initiated, owing to increasing interest in 
their conservation status, that have greatly added to our knowledge 
about the nesting and breeding behavior of this species. On Agattu 
Island, an additional 86 active nests have been found and monitored 
(Kaler, Service, 2008-2011, unpublished data), 9 nests have been found 
on Adak Island (Kenney 2012, in litt.; Kenney and Kaler 2013, p. 74), 
75 have been found on Kodiak Island (Corcoran and Mackey, 2012, p. 1; 
Lawonn 2012, p. 10), and 35 have been found in the glaciated landscape 
around Icy Bay (Kissling, unpublished data). To date, 234 Kittlitz's 
murrelet nests have been found in Alaska (n=230; 98 percent) and Russia 
(n=4; 2 percent) (Felis, U.S. Geological Survey, 2013, unpublished 
data).
    Based on these recent efforts, some generalities can be made about 
nesting habitat and nest site selection of the Kittlitz's murrelet. 
Their nesting habitat is characterized by sparsely vegetated or 
unvegetated scree-fields, talus slopes, barren ground, and cliff and 
rock ledges in the coastal uplands and mountains, often in the vicinity 
of glaciers or in historically-glaciated areas (Day et al. 1983, pp. 
267-269; Day 1995, pp. 271-273; Konyukhov et al. 1998, p. 322; Piatt et 
al. 1999, p. 8; Kaler et al. 2009, p. 366; Lawonn 2012, pp. 83-87; 
Kissling, unpublished data). Rangewide, barren areas, which are 
characterized by bare rock, gravel, sand, silt or clay with little or 
no ``green'' vegetation present appear to be the preferred nesting 
habitat the Kittlitz's murrelet owing to disproportionate use relative 
to availability (Kaler et al. 2009, p. 366; Lawonn 2012, pp. 90, 101-
102; Felis, unpublished data; Kissling, unpublished data). In parts of 
this species' range, such as Kodiak Island, where mammalian predators 
exist, the Kittlitz's murrelet appears to avoid nesting near vegetated 
edges (Lawonn 2012, pp. 90, 101). Dwarf shrub and herbaceous habitats 
occasionally are used by nesting Kittlitz's murrelets, especially in 
the Aleutian Islands where nests are positively associated with orange 
crustose lichens (Xanthoria spp.) (Kaler et al. 2009, p. 366; Kenney 
and Kaler 2013, pp. 73-74), and where this habitat type is abundant. 
Nesting habitat of the Kittlitz's murrelet is located adjacent to or 
associated with glaciers and persistent snow only in south-coastal 
Alaska where these land cover classes currently exist. Generally, the 
amount of vegetative cover within a 25-m radius of nest sites is least 
in glaciated areas of south-coastal Alaska (3 percent) (Kissling, 
unpublished data), moderate on Kodiak Island (9 percent) (Lawonn, p. 
102) and northern Alaska (14 percent) (Felis, unpublished data) and 
greatest in the Aleutian Islands (51 percent) (Kaler et al. 2009, p. 
366). Despite variation in percent of vegetative cover near nests among 
these study sites, Kittlitz's murrelets consistently nest in the least 
vegetated areas available on the landscape within a particular area 
(Lawonn 2012, p. 90; Kaler, unpublished data; Kissling, unpublished 
data), presumably to maximize the safety of the nest from predators.
    Although the amount of vegetative cover appears to drive nest site 
selection for the Kittlitz's murrelet both within areas and across 
their range, other characteristics may also be important. Many of these 
factors, such as elevation, slope, distance to ocean, aspect, 
substrate, and local climate, however, often are correlated with low 
vegetative cover. For example, unvegetated or sparsely vegetated areas 
tend to occur at higher elevations and on steeper, windward-facing 
slopes. Moreover, the variation in these attributes across the species' 
range makes it difficult to draw generalizations about their 
importance. For example, nests have been found from 0.1 to 45.7 mi (0.2 
to 73.5 km) from the ocean, on slopes 0-66 degrees, and at elevations 
between 419 and 7,378 ft (128 and 2,249 m) above sea level. In general, 
nests located on the steepest slopes and at the highest elevations 
occur in south-coastal Alaska, whereas those farthest from the ocean 
are located in northern Alaska (Felis, unpublished data), but this may 
reflect overall differences in habitat available. Nest orientation is 
similarly uninformative at the rangewide scale; based on 196 nests with 
documented aspect, 50 (26 percent) faced north, 56 (29 percent) faced 
east, 40 (20 percent) faced south and 50 (26 percent) faced west (Day 
et al. 1999, 25-26; Lawonn 2012, p. 84; Kaler, unpublished data; 
Kissling, unpublished data; summarized by Felis, unpublished data), 
suggesting that nest site aspect is not relevant (Kaler et al. 2009, p. 
366) or is locally driven (e.g., on Kodiak Island) (Lawonn 2012, pp. 
83-84). The importance of small- and medium-sized rocks (roughly 2.0- 
11.8 inches [in]) (5-30 centimers [cm]) at and near nests has been 
reported at several study sites (Day et al. 1983, p. 267; Kaler et al. 
2009, p. 366; Lawonn 2012, p. 89; Kissling, unpublished data).
    Similar to that of the marbled murrelet, much of the behavior and 
life history of the Kittlitz's murrelet appears to have evolved around 
predator avoidance, particularly during nesting (Nelson and Hamer 1995, 
p. 66). While most alcids avoid predators by nesting in inaccessible 
areas (burrows, crevices) or on open rock ledges and protect their 
young by nesting in large colonies or by guarding them, the Kittlitz's 
murrelet places its nest in habitats expected to support low numbers of 
predators, disperses nests across the landscape, and relies on cryptic 
coloration and behavior to avoid predator detection. On the mainland in 
south-coastal Alaska, nunataks appear to be favorable habitats 
presumably because of their isolation from terrestrial predators 
(Kissling, unpublished data). On Kodiak Island, the median within-year 
nearest neighbor distance was found to be 1,128 ft (range=42-5,085 ft) 
(344 m; range=13-1,550 m) (Lawonn 2012, p. 83). In addition to site 
selection, murrelets have a variety of morphological and behavioral 
characteristics to minimize detection by potential predators 
(summarized by Nelson and Hamer 1995, p. 66).
    A single egg is laid in a nest scrape composed of sand- and pebble-
sized rocks (more typical in northern Gulf of Alaska) or plant matter 
(moss and lichens; common in western Aleutian Islands) at the base of a 
large rock or on a cliff ledge (Day et al. 1983, p. 267; Piatt et al. 
1994, p. 55; Piatt et al. 1999, p. 11; Day 1995, pp. 271-273; Kaler et 
al. 2009, p. 366; Lawonn 2012, pp. 81-82; Kaler 2012, in litt.; Kenney 
and Kaler 2013, p. 73; Kissling, unpublished data). The egg is colored 
pale-green, olive-green, or blue-green with brown mottling, ranging 
from speckling to streaking (Day et al. 1983, pp. 265-266; Piatt et al. 
1994, p. 55; Kaler et al. 2009,

[[Page 61769]]

p. 367). Across their range and within areas, egg laying is highly 
asynchronous, with records ranging from 6 May through 17 July (Day 
1996, p. 435; Kaler et al. 2009, pp. 366-367; Corcoran and Mackey 2012, 
p. 10; Lawonn 2012, p. 21; Kissling, unpublished data). There is some 
evidence that Kittlitz's murrelets attempt to renest when a nest fails 
(Kaler and Kenney 2008, p. 16; Kenney and Kaler 2013, p. 73; Kissling, 
unpublished data).
    The duration of incubation is approximately 30 days (Day et al. 
1999, p. 14; Kaler et al. 2009, p. 365). Both parents incubate the egg, 
and loss of a parent can mean failure of the nest (Kissling, 
unpublished data). Mean hatching dates range from 6 July in Icy Bay 
(Kissling, unpublished data), to 8 July on Kodiak Island (Corcoran and 
Mackey 2012, pp. 10-11; Lawonn 2012, pp. 21, 47), and to 17 July on 
Agattu Island (Kaler, unpublished data); these are consistent with the 
known or expected hatching dates by geographic region presented by Day 
et al. (1996, p. 435), which range from 14 June in southeastern Alaska 
to 28 July in the Chukchi Sea. Like the marbled murrelet, Kittlitz's 
murrelet chicks are semiprecocial and are brooded for approximately 48 
hours (Nelson and Hamer 1995, p. 66; Lawonn 2012, pp. 23-24). This 
short period of brooding requires that thermoregulatory capability be 
developed quickly after hatching so that the chick can remain 
unattended and have minimal parental care other than food deliveries.
    The chick is fed fish for 21-40 days post-hatch at a rate of 1-12 
times per day with considerable variation among individual nests, study 
areas, and years (Day et al. 1999, p. 15; Kaler et al. 2011, p.15; 
Lawonn 2012, p. 51; Kissling, unpublished data). Both adults feed the 
chick throughout the day and night (Day et al. 1999, p. 15; Kaler et 
al. 2011, p. 16; Kissling, unpublished data), but most meal deliveries 
occur in the early morning within a 4-hour period around sunrise 
(Lawonn 2012, p. 26). Similar to those of the marbled murrelet, 
Kittlitz's murrelet chicks maintain their camouflaging down until just 
prior to fledging (Nelson and Hamer 1995, p. 60; Kaler et al. 2009, p. 
367). When they fledge, chicks are 40-60 percent of adult body mass, 
but their wing length is nearly adult-sized (Day et al. 1983, p. 272; 
Kaler et al. 2009, pp. 368-369; Lawonn 2012, p. 60). Their initial 
flight from the nest to the ocean can be short from island nests (Kaler 
et al. 2009, p. 371; Lawonn 2012, p. 101), or much longer from mainland 
nests that have been recorded as far as 46 mi (74 km) from the ocean 
(Day et al. 1983, p. 272). Russian scientists have speculated that 
newly-fledged Kittlitz's murrelets stage on upland glacial lakes before 
departing for the ocean, but this hypothesis has not been substantiated 
(Kuletz et al. 2008, p. 13), although low numbers of adult Kittlitz's 
murrelets have been observed on freshwater lakes during the breeding 
season (Savage 2013, in litt.; Walsh 2013, in litt.). There also is the 
possibility that fledglings fly downslope to the nearest river from an 
inland site and use the river as transportation or orientation to the 
ocean, but this behavior has not been documented (Day et al. 1983, p. 
272).

Demography

    Although demographic data are sparse, Kittlitz's murrelets exhibit 
life-history characteristics that are similar to other alcids, such as 
fairly long lifespan (assumed to be approximately 15 years), delayed 
reproductive maturity (assumed to be approximately 3 years of age), 
intermittent breeding (i.e., they do not appear to breed annually), and 
low rates of reproduction (Bessinger 1995, p. 385; De Santo and Nelson 
1995, pp. 36-37; Begon et al. 1996, pp. 494-496; Day et al. 1999, p. 
16; Gaston 2004, pp. 164-167). This life-history strategy depends on 
the survival of at least a few offspring and recruitment of those 
offspring into the adult breeding population to maintain population 
stability. Generally, for a species with this life history strategy, 
changes in mortality rates of reproductively capable adults have 
greater population-level effects compared to those of juvenile or sub-
adult birds and to changes in reproductive rates; in contrast, for a 
species that is shorter lived, produces more offspring, and matures at 
an earlier age, changes in reproductive rates tend to drive population-
level effects (Ricklefs 1977, p. 467-468; Roff 1992, p. 45; Beissinger 
1995, p. 390).
    Reproductive Performance. Assessing reproductive effort and 
performance of the Kittlitz's murrelet is particularly challenging 
because of their non-colonial and purposefully cryptic nesting 
behavior. Low reproductive success has been both suggested (Day and 
Nigro 2004, pp. 91-94) and documented in Kittlitz's murrelets (Kaler et 
al. 2009, p. 369; Lawonn 2012, pp. 29-30; Kaler, unpublished data; 
Kissling, unpublished data). Because nesting behavior and nesting 
success have been monitored for only a few years (since 2006) and only 
in a few locations, it is unclear whether this low rate of nesting 
success is typical for the Kittlitz's murrelet, a species in which a 
breeding pair needs to produce offspring only infrequently, or whether 
one or more environmental parameters have changed, causing decreased 
breeding effort or increased egg and chick mortality.
    In total, 206 active nests of the Kittlitz's murrelet have been 
monitored, nearly all of which were discovered as part of studies 
initiated since 2006 on Agattu and Kodiak islands and Icy Bay (south-
coastal Alaska) (Naslund et al. 1994, p. 46; Kaler et al. 2009, p. 363; 
Lawonn 2012, p. 10; Corcoran and Mackey 2012, p. 1; Kenney 2012, in 
litt.; Kaler, unpublished data; Kissling, unpublished data). The 
majority of these nests (74 percent) failed; only 23 percent 
successfully fledging a chick; the nest fate was not able to be 
determined at 3 percent of the nests. Overall, most of the nest 
failures were attributed to depredation of the egg or chick (31 
percent) and death of the chick (starvation, exposure or disease; 29 
percent), followed by unknown cause (21 percent), abandonment (14 
percent), accident (3 percent), and parent mortality (2 percent). When 
analyzed collectively, estimates of daily nest survival ( 
standard error [SE]; standard error is a measure of variability in the 
data) at the three locations where nests where regularly monitored were 
slightly higher in Icy Bay (0.9790.005) than at Kodiak and 
the Aleutian islands (0.9680.003) (see Factor A discussion 
for more details on this analysis). Across the 55-day nesting period, 
these daily nest-survival rates extrapolate to estimates of nesting 
success of 0.307 and 0.166, respectively. Nest observations from the 
three locations where nests were regularly monitored are summarized 
below, as well as observations of juveniles at sea.
    Aleutian Islands--Since 2005, 96 active Kittlitz's murrelet nests 
have been found in the Aleutian Islands (Agattu=87 and Adak=9) (Kaler 
et al. 2009, p. 366; Kenney 2012, in litt.; Kenney and Kaler 2013, p. 
74; Kaler, unpublished data). Nests were found using searches conducted 
on foot owing to the low, scrubby vegetation and rolling hills (Kenney 
and Kaler 2013, pp. 73-74). From 95 nests of known fate, 18 chicks 
successfully fledged (19 percent apparent nesting success; range among 
years=6-44 percent) (Kenney 2012, in litt.; Kaler, unpublished data), 
and the fate of one chick was unknown because researchers left the 
island before its fate was determined (Kaler et al. 2009, p. 369). Of 
the 77 failed nests, the apparent cause of nest failure was chick death 
due to starvation and exposure (40 percent), depredation of egg or 
chick (25 percent), unknown cause (21 percent), failure of eggs to

[[Page 61770]]

hatch followed by abandonment (12 percent), or accident (2 percent). 
Kaler et al. (2011, p. 17) could not definitively assign the causes of 
chick mortality to either exposure or starvation because multiple 
factors including diet, weather, and provisioning rates by adults were 
likely contributors. Fledglings in the Aleutian Islands were 
approximately 50 percent of the adult body mass (Kaler et al. 2009, pp. 
368, 370-371). This percentage is lower than that calculated for 
marbled murrelets (58-70 percent) (Kuletz and Marks 1997, p. 423; 
Nelson and Hamer 1995, p. 60; Kissling, unpublished data) and for 
Kittlitz's murrelets that fledged from Kodiak Island (58 percent) 
(Lawonn 2012, p. 60) and Icy Bay (63 percent) (Kissling, unpublished 
data), but is greater than a Kittlitz's murrelet fledgling found on the 
Kenai Peninsula (40 percent) (Day et al. 1983, p. 272). The low 
fledging weight in the Aleutian Islands was most likely due to the poor 
quality (i.e., low lipid content) of prey delivered to chicks, which 
included mostly hexagrammids (40 percent of deliveries at 10 nests 
monitored), sand lance (36 percent), and gadids and rockfish (24 
percent), and was reflected in the high prey delivery rates at nests in 
the Aleutians (9.8 fish per day) (Kaler, unpublished data), which was 
nearly double the rates observed in the northern Gulf of Alaska (Lawonn 
2012, pp. 27, 55; Kissling, unpublished data).
    South-central Alaska--In 1994, one active Kittlitz's murrelet nest 
was opportunistically found and monitored using a remote video camera 
on Red Mountain near Kachemak Bay (Naslund et al. 1994, p. 46; Piatt et 
al. 1994, p. 55). The chick fledged and the nest was deemed to be 
successful (Naslund et al. 1994, p. 46).
    In 2006, an active nest that contained a live Kittlitz's murrelet 
nestling was found opportunistically on Kodiak Island, although the 
fate of this nest was not confirmed (Stenhouse et al. 2008, p. 59). 
Since then, 74 additional nests have been found by systematically 
searching areas of apparently suitable habitat on foot in a pre-defined 
study area (Corcoran and Mackey 2012, p. 1; Lawonn 2012, p. 21). Of 
these 74 nests, 16 chicks fledged from 71 nests (23 percent apparent 
nesting success) and nest fate of 3 nests was unknown. The overall 
annual nest survival rate (number of chicks fledged per nesting pair) 
was 0.0933 (95 percent CI = 0.0067 to 0.2991) between 2008 and 2011, 
almost certainly below 30 percent nesting success (Lawonn 2012, p. 30). 
Nest failures were most commonly caused by depredation (54 percent), 
followed by chick death (25 percent) and abandonment (20 percent); one 
nest failed for unknown reasons (Corcoran and Mackey 2012, p. 3; Lawonn 
2012, p. 59). The red fox (Vulpes vulpes) was the only identified nest 
predator (13 of 15 predation events recorded; two unidentified 
predators) (Corcoran and Mackey 2012, p. 3; Lawonn 2012, pp. 30-31). In 
2011 and 2012, nine dead chicks found in nest scrapes of monitored 
nests were necropsied, and all were in fair to good body condition, 
suggesting that nutritional health was not responsible for their death 
(Shearn-Bochsler et al. 2013, p. 1). However, at least six of these 
chicks had high levels of saxitoxin, a neurotoxin produced by certain 
species of dinoflagellates, in their gut and/or liver, which is 
believed to have caused the death of these chicks immediately after 
consuming sand lance (Shearn-Bochsler et al. 2013, p. 1). Chick meal 
delivery rates (1 standard deviation [SD]; standard 
deviation is a measure of variability in the data) averaged 4.6 (0.8) fish per day or 117 (37) fish from hatching to 
fledging of the chicks with sand lance being the most common prey 
delivered (92 percent of deliveries), followed by capelin (8 percent) 
and a few herring and salmonids (Oncorhynchus spp.) (Lawonn 2012, pp. 
27-28, 55). On Kodiak Island, the mean number of days to fledging 
(SD) was 24.8 (2.3) days (Lawonn 2012, p. 55), 
or lower than that for nests monitored at Agattu Island (30.65.6 days) (Kaler, unpublished data), despite comparable apparent 
nesting success at these study sites where similar methods were used to 
locate and monitor Kittlitz's murrelet nests.
    Southeastern Alaska--In contrast to Kodiak, Adak, and Agattu 
islands, the terrain in southeastern Alaska is characterized by steep 
mountains, icefields, and glacial fjords usually with thick vegetation 
along the near shore areas precluding nest searching efforts by foot. 
Thus, from 2007 to 2012, 35 Kittlitz's murrelet nests have been located 
in Icy Bay by tracking 24-44 radio-marked birds throughout each of the 
six breeding seasons (Kissling, unpublished data). Thus, this is the 
only study site where some reproductive measures, such as breeding 
propensity and adult body condition prior to breeding, are available 
and where nest locations are seemingly unbiased because all habitats 
within the study area were available to the marked birds for nesting 
(as opposed to searching a specified area that consists of presumably 
suitable nesting habitat). The mean proportion of radio-marked 
murrelets that attempted to nest annually was 0.18 (range=0.03-0.43 
across all years), but because weather and logistics precluded daily 
aerial tracking, it is possible that early failed breeders were not 
detected and that this estimate of breeding propensity is biased low. 
Therefore, Kissling (unpublished data) used a combination approach to 
estimate breeding propensity that includes quantifying levels of 
vitellogenin (an egg-yolk precursor protein expressed only in females), 
brood patch development (necessary for incubation in both sexes), and 
radio-telemetry (following Peery and Henry 2010, p. 2417). Using the 
combination method, the proportion of murrelets attempting to breed was 
0.87 (range=0.75-1.00), which is probably biased high because brood 
patches can be an unreliable indicator of reproductive status 
(McFarlane Tranquilla et al. 2003, p. 112). It is difficult to 
reconcile the range in estimates of breeding propensity (0.18-0.87; 
mean=0.52; breeding propensity is defined as the probability that an 
after-second-year murrelet will breed in a given year), and it is 
impossible to determine the accuracy of either method because in 
glacial-dominated landscapes such as Icy Bay, alternative field methods 
to locate nests do not currently exist. Many adult Kittlitz's murrelets 
arrive in Icy Bay paired with a mate and in apparently good body 
condition, suggesting perhaps that certain environmental cues may be 
required for breeding to proceed. Another possible explanation for the 
variable breeding-propensity rate is that there is a capture, handling, 
or radio-transmitter effect on individual Kittlitz's murrelets; 
however, several lines of evidence, including few juveniles observed at 
sea and good reproductive performance of radio-marked marbled murrelets 
(see below), suggest that this possible issue is not significant.
    Because most (86 percent) nests in Icy Bay were not accessible due 
to the dangerous terrain, nest fate often was inferred (following 
Bradley et al. 2004, pp. 321-322), but nests occasionally (n=5) could 
be monitored with video or still cameras. Apparent nesting success 
across all years combined was 40 percent (14 of 35 nests). Causes of 
failure were largely unknown (71 percent of failed nests) because most 
of the nests were inaccessible, but of those where cause of failure 
could be determined or inferred, three failed due to parent mortality 
(predation) during incubation, two failed due to unstable terrain 
(i.e., a rockfall), and one egg was abandoned. Despite the small sample 
sizes, successful nests (n=14) were

[[Page 61771]]

located closer to the ocean (median distance=5.6 mi [9.0 km]) than 
failed nests (n=21; median distance=15.0 mi [24.1 km]); the elevation 
of nests did not affect nest fate (4,226 ft [1,288 m] for successful 
nests and 4,718 ft [1,435 m] for unsuccessful nests). Prey deliveries 
averaged 3.0 fish per day (n=2 nests) and consisted primarily of sand 
lance (58 percent) and capelin (21 percent) with smaller amounts of 
smelt (9 percent), herring (6 percent) and snake prickleback (Lumpenus 
sagitta; 6 percent). The mean number of days to fledging (1 
SD) at 9 nests was 23.7 (3.5) days, or comparable to nests 
monitored at Kodiak Island.
    In addition to Kittlitz's murrelets, researchers captured and 
radio-marked marbled murrelets in 2011 (n=7) and 2012 (n=9) in Icy Bay 
to compare reproductive performance between the two closely related 
species (Kissling, unpublished data). Across both years, 11 of 16 (69 
percent) radio-marked marbled murrelets attempted to nest (two actually 
renested successfully), and 9 of 13 nests were successful (69 percent 
apparent nesting success). Marbled murrelet nests were located at lower 
elevations (median elevation=1,368 ft [417 m]) and closer to the ocean 
(median distance=2.9 mi [4.7 km]) than were Kittlitz's murrelet nests 
(4,291 ft [1,308 m] and 8.8 mi [14.2 km], respectively). Both breeding 
propensity and nest success of marbled murrelets were far greater than 
that for Kittlitz's murrelets using the same techniques in the same 
study area. Although the sample sizes are small, these results are 
important for two reasons: (1) It is unlikely that there was a capture, 
handling or radio-transmitter effect negatively biasing the poor 
reproductive measures of Kittlitz's murrelets, assuming that Kittlitz's 
and marbled murrelets would respond similarly; and (2) despite their 
similar life histories, Kittlitz's murrelets were consistently 
outperformed reproductively by marbled murrelets in Icy Bay, suggesting 
perhaps that forage-fish abundance was not limiting the nesting success 
of Kittlitz's murrelets. Possible reasons for the differences in 
reproduction of the two species are reduced foraging efficiency of 
Kittlitz's murrelets, availability of suitable nest sites, carry-over 
effects from the non-breeding period (Sorensen et al. 2009, p. 464), or 
increased energetic costs of Kittlitz's murrelets to access nests at 
higher elevations and farther from the ocean (Hatch 2011, pp. 86-87).
    Juveniles at sea--Juvenile and adult Kittlitz's murrelets are 
readily distinguishable in hand owing to plumage characteristics, and 
usually, the presence of an egg-tooth in juveniles (Kissling, 
unpublished data); however, these identification markers are not easily 
observed at a distance at sea, especially in August when fledglings 
arrive on the water and adults begin their concurrent pre-basic molt 
(Kuletz et al. 2008, p. 34). This complication may prevent the accurate 
estimation of juvenile abundance and ratios of juveniles to adults, 
both of which have been used as indices to annual reproductive success 
of marbled murrelets (Beissinger 1995, pp. 391-392; Kuletz and Kendall 
1998, pp. 450-455; Beissinger and Peery 2007, pp. 297-298; Kuletz et 
al. 2008, p. 85).
    Day and Nigro (2004, pp. 91-93) suggested that reproductive success 
in Kittlitz's murrelets may be very low based on the near absence of 
juvenile birds in late summer surveys in Prince William Sound. In 3 
combined years of at-sea surveys conducted between 15 July and 15 
August in 1996, 1997, and 1998, in the fjords of Prince William Sound, 
only a single hatch-year bird was sighted (Day and Nigro 2004, p. 91). 
During similar late summer surveys in Kachemak Bay from 2004 to 2007, 
densities of juvenile Kittlitz's murrelets varied among years 
(range=0.01-0.05 birds per square mile (mi\2\) [0.03-0.12 birds per 
square kilometer (km\2\)]) and were much lower than those of marbled 
murrelets (range=0.10-0.31 birds per mi\2\ [0.27-0.79 birds per 
km\2\]); however, juvenile to adult ratios were comparable between 
species ranging from 0.01 to 0.28 for Kittlitz's murrelets and from 
0.02 to 0.13 for marbled murrelets, albeit with less intra-annual 
variation for the latter species (Kuletz et al. 2008, pp. 59, 85). To 
provide perspective, the total number of juvenile Kittlitz's murrelets 
recorded in the 4 years of surveys was 37 among 1,445 sub-adults and 
adults (Kuletz et al. 2008, pp. 104-107). Similarly, during surveys of 
nearshore waters around Kodiak Island in August 2011 and 2012, 16 
juvenile and only 6 sub-adults and adult Kittlitz's murrelets were 
observed compared to 187 juvenile and 5,779 sub-adults and adult 
marbled murrelets (Corcoran 2012, p. 5). Between 2008 and 2011, only 5 
juvenile to 380 adult Kittlitz's murrelets were captured in late summer 
in Icy Bay (Kissling, unpublished data). Thus, results of all of these 
studies are difficult to interpret without information on the behavior 
and timing of movements of both age classes of Kittlitz's murrelets in 
late summer and some estimates of detection errors. Fairly high ratios 
of juveniles to adults in Kachemak Bay and Kodiak Island suggest good 
reproductive performance in these areas, yet nest monitoring data on 
Kodiak Island indicate differently; therefore, the high ratios may 
reflect rapid and synchronous departure of adult Kittlitz's murrelets 
from these areas or post-fledging dispersal of juvenile Kittlitz's 
murrelets into these areas.
    In Icy Bay, six juvenile Kittlitz's murrelets (1 immediately prior 
to fledging, 3 newly fledged, and 2 approximately 2-3 weeks post-
fledgling) were captured and radio-marked in 2008-2010 (Kissling, 
unpublished data). All juveniles still had their egg-tooth at the time 
of capture. The 3 newly fledged birds were located within Icy Bay for 
approximately 24 hours before departing; 2 of them were not detected 
again, but 1 returned to Icy Bay 8 days later. The older fledglings, 
which were significantly heavier than the newly fledged birds, were 
relocated in Icy Bay for 1-3 weeks post-marking. All juveniles were 
relocated visually and appeared to be good swimmers and divers, 
although the newly fledged birds were not readily capable of flight, in 
contrast to the older fledglings that were excellent flyers and were 
indistinguishable from flying adults both in terms of flight ability 
and plumage. The small sample size precludes drawing definitive 
conclusions; however, these results suggest that most newly fledged 
Kittlitz's murrelets immediately depart their breeding area. After 
becoming proficient at foraging on their own, gaining weight and 
improving flight capability to avoid predators, they may return to 
their breeding area where they remain until the post-breeding migration 
begins. This possible scenario explains the differences in behavior 
between the newly fledged and post-fledged Kittlitz's murrelets. A 
better understanding of juvenile behavior after fledging would help to 
determine the reliability of juvenile surveys in late summer, which may 
be the most realistic and cost-efficient method for long-term 
monitoring of reproductive performance across many different study 
sites, as it is for marbled murrelets.
    Survival. The only estimates of survival of Kittlitz's murrelets 
were derived from data collected in Icy Bay. Using radio-marked 
Kittlitz's murrelets (n=197), Kissling (unpublished data) estimated 
breeding season survival (60 days post-marking; approximately mid-May 
through mid-July) of adults greater than 1 year old to be 0.89 
(SE=0.04) with little inter-annual variation (n=6 years). The primary 
cause of adult mortality in the breeding season in Icy Bay was 
predation by peregrine falcons

[[Page 61772]]

(Falco peregrinus) and bald eagles (Haliaeetus leucocephalus). Based on 
mark-recapture banding methods, annual survival (1 July to 30 June) of 
adult Kittlitz's murrelets was estimated to be 0.80 (SE=0.33). Although 
this estimate is imprecise, primarily because of low recapture rates 
across years (less than 8 percent), it is comparable to annual survival 
of marbled murrelets (0.83-0.88) estimated using similar methods (Cam 
et al 2003, p. 1122; Peery et al. 2006, p. 83). There are no estimates 
of juvenile survival of Kittlitz's murrelets, but estimates of annual 
survival of juvenile marbled murrelets range from 0.51 based on radio-
telemetry (Parker et al. 2003, p. 207) to a proportion of adult 
survival (70 percent) by comparing with other alcids (Nur 1993 in Piatt 
et al. 2007, p. 55).
Population Status and Trends
    In this section, we summarize information on status and trends of 
the Kittlitz's murrelet at the local population scale (i.e., by 
individual study areas) and at a broad scale across multiple 
populations. We also describe difficulties in estimating population 
size and trends of the Kittlitz's murrelet.
    Estimating abundance and population trends for most alcids is 
simpler than for the Kittlitz's murrelet because the majority of alcids 
nest in colonies where birds concentrate and can be monitored in large 
numbers during the breeding season. In contrast, the solitary, remote, 
and secretive nesting behavior of the Kittlitz's murrelet makes 
terrestrial monitoring impractical for the purposes of estimating 
abundance and population trends (Drew and Piatt 2008, p. 179). 
Therefore, estimating abundance and the rate of change in populations 
of Kittlitz's murrelets has relied entirely on at-sea surveys (Day 
2011, p. 2).
    A handful of ornithological surveys and expeditions primarily aimed 
at documenting the distribution of marine birds occurred prior to 1972 
(Isleib and Kessel 1973, p. 1), when systematic at-sea surveys were 
conducted in a few select locations in Alaska (Bailey 1977, p. 60; 
Klosiewski and Laing 1994, p. 5) and along discontinuous sections of 
shoreline in Russia (summarized in Artukhin et al. 2011, pp. 25-26). 
Since then, many surveys for marine birds, including a number of 
efforts specifically for the Kittlitz's murrelet, covering a wider 
geographic area have been conducted and, in some areas, repeated in 
subsequent but not necessarily continuous years. These historical and 
recent survey efforts have provided a tremendous amount of information 
on the distribution and abundance of the Kittlitz's murrelet within the 
areas surveyed. Nonetheless, inherent, methodological, and analytical 
difficulties in estimating population size and trend of this species 
remain, many of which are not mutually exclusive and some of which can 
be resolved as new information becomes available.
    First, present-day populations of Kittlitz's murrelet occupy a 
large range and are geographically clustered, usually in remote areas 
that are difficult to reach and survey. Many areas of their range have 
not yet been systematically surveyed or are under-represented by 
existing survey efforts.
    Second, the high at-sea spatial and temporal variation of 
Kittlitz's murrelets often results in wide variances associated with 
population estimates and therefore little power to detect trend 
(Kissling et al. 2007, p. 2168; Kirchhoff 2011, pp. 79-80; but see Drew 
et al. 2008, pp. 18, 41). Each surveyed area differs in size, which has 
implications for estimating abundance. Surveys attempting to encompass 
larger areas, such as Prince William Sound, may encompass the spatial 
variability of murrelets that use this area during the summer; that is, 
surveys may be sufficiently large to encompass the spatial variation in 
areas used by murrelets during a survey effort owing to daily or weekly 
movements by murrelets within that area. However, larger areas take 
longer to survey and thus must capture the temporal variability in 
murrelet abundance. None of the survey areas, except Icy Bay (see 
Nesting and Demography, above), has been accompanied by related studies 
of daily (or longer) movements by murrelets to help understand whether 
the at-sea surveys are encompassing the range of habitats used by 
murrelets in that area during the survey period.
    Third, the Kittlitz's murrelet can be difficult to distinguish from 
the more common marbled murrelet during surveys, resulting in varying 
proportions of Brachyramphus murrelets identified to genus only. This 
issue was particularly problematic during earlier surveys (pre-2000), 
when there was less emphasis and training on distinguishing between the 
two species during surveys of all marine birds, occasionally leading to 
high proportions (greater than 50 percent) of unidentified murrelets 
(Piatt et al. 2011, p. 66; Day 2011, pp. 22-27; Kuletz et al. 2011a, p. 
99; Kuletz et al. 2011b, pp. 87, 90) and possibly unknown proportions 
of misidentified murrelets (Kirchhoff 2011, pp. 80-81; Hodges and 
Kirchhoff 2012, p. 117; Kuletz et al. 2013, p. 69).
    Fourth, owing to their asynchronous arrival at breeding sites, 
unknown fidelity to breeding areas, and movements during the breeding 
season, it is difficult to define both a statistical or biological 
population of Kittlitz's murrelets. Therefore, apparent trend in local 
population size of the Kittlitz's murrelet is confounded by intra- and 
inter-annual movements of individuals among study sites. Most 
Kittlitz's murrelets apparently do not breed annually (Day and Nigro 
2004, p. 91; Kissling, unpublished data) and, therefore, are not 
restricted to a particular breeding site or at-sea areas near a 
breeding site every year, allowing non-breeding individuals and failed 
breeders to move freely to locate food during the breeding season when 
most surveys are conducted. While breeding birds may not be counted on 
surveys because they are incubating or tending to young at nests, this 
probably is minor because breeding propensity typically appears to be 
low in this species (see Reproductive Performance, above).
    In Icy Bay, the daily emigration rate of radio-marked Kittlitz's 
murrelets (SE) over a 60-day period during the breeding 
season was low (0.0080.002) (Kissling, unpublished data), 
but no estimate of the rate of immigration exists. Similarly, the 
annual recapture probability of uniquely banded Kittlitz's murrelets 
(SE) was low (0.080.03), suggesting that 
individuals do return to the area, but perhaps not annually (Kissling, 
unpublished data). These intra- and inter-annual movements complicate 
reliable trend estimation of local population size, especially because 
the timing of at-sea surveys for the Kittlitz's murrelet has not been 
synchronized among study sites. To illustrate an extreme example, the 
local population of Kittlitz's murrelet in Kachemak Bay was estimated 
to be 1,776 birds (SE=1,051) in 2005, but 3,277 birds (SE=1,582) in 
2006, followed by a drastic reduction in 2007 to 1,086 birds (SE=931) 
(Kuletz et al. 2011b, p. 96). The documented fluctuations in local 
population size over the 3-year period cannot be demographically 
explained and therefore probably are related to intra- or inter-annual 
movements into or out of Kachemak Bay.
    Fifth, there is not a consistent survey protocol or design used to 
count Kittlitz's murrelets at sea across locations and occasionally at 
the same location (Day 2011, pp. 6-39). Key survey and analytical 
procedures such as time of year and synchrony of counts across range, 
level of surveyor expertise and training, limitations of oceanic and 
climatic conditions, varying survey platforms, estimation of detection 
probabilities, inclusion of flying

[[Page 61773]]

murrelets, survey objectives (single-species versus multi-species 
surveys), and treatment of unidentified murrelets in population-size 
estimation have varied among locations and years (Hoekman et al. 2011, 
p. 35; Kirchhoff 2011, p. 78; see Day 2011 for complete review). Within 
a study site, many methodological issues have been addressed in recent 
years, but across sites, inconsistencies will remain until a 
comprehensive monitoring protocol is developed, accepted and 
implemented by researchers. Until then, our ability to detect 
population trend of Kittlitz's murrelet reliably, especially beyond 
individual study sites, is limited (Day 2011, pp. 52-57).
    Recognizing all of these challenges and differences in methods 
across study sites, the rangewide population of Kittlitz's murrelet 
currently is estimated to be 33,583 birds (95 percent CI=25,620-
41,546). Because some areas remain unsurveyed or have not been surveyed 
in many years, this estimate should be considered a minimum. The 
rangewide estimate was derived by summing the most recent local 
population estimate in all surveyed areas during the breeding season, 
which includes all known concentrations of Kittlitz's murrelet. These 
areas (and most recent survey year) include the mainland fjords of 
southeastern Alaska (2002) (Kissling et al. 2011, p. 7), Glacier Bay 
(2010-2012, averaged) (Hoekman et al. 2013, p. 15), the outer coast of 
southeastern Alaska from Cross Sound to Yakutat (2003-2004) (Kissling 
et al. 2011, p. 7), Yakutat Bay (2009) (Kissling et al. 2011, p. 7), 
Lost Coast extending from Manby Point (2002) to Duktoth River (2008-
2009) (Kissling et al. 2011, p. 7), Icy Bay (2012) (Kissing, 
unpublished data), Kenai Fjords (2008) (Arimitsu et al. 2011, p. 18), 
Prince William Sound (2012) (Cushing, Oregon State University, 2010-
2012, unpublished data), Kachemak Bay (2011) (Kuletz, Service, 2011, 
unpublished data), Lower Cook Inlet (1996) (Kuletz et al. 2011b, p. 
96), Kodiak (2012) (Corcoran 2012, p. 5), southern coast of the Alaska 
Peninsula (2003) (Madison et al. 2011, p. 118), select Aleutian Islands 
(2004-2009) (Madison et al. 2011, p. 118), northern Alaska including 
Chukchi and Beaufort seas and Arctic Ocean (2000-2009) (Day et al. 
2011, p. 58), eastern coast of Russia extending from the Chukotka 
Peninsula in the north to the southern tip of the Kamchatka Peninsula 
(1991-2005) (Artukhin et al. 2011, pp. 26-28) and the northern Sea of 
Okhotsk (2005-2008) (Artukhin et al. 2011, p. 30). Hence, this 
population estimate does not include numbers from Kodiak Island, most 
of the Aleutian Islands, and the Bering Sea, plus non-breeding birds 
that may be living at sea across the open northern Gulf of Alaska.
    We examined trends of the Kittlitz's murrelet at the local 
population scale and across multiple populations. We defined a 
population as the birds using pre-defined study area boundaries, 
although there is no evidence that these individual populations are 
biologically separated from one another. Below, we briefly summarize 
available information about local population trends of the Kittlitz's 
murrelet in areas for which a sufficient number of years of data were 
available. In many cases, we were unable to draw inferences on the 
trend of Kittlitz's murrelet at the local population scale because of 
the difficulties described above and, in some cases, conflicting 
information within a study area. However, we did not consider this to 
be a limitation to our assessment because our primary interest was to 
determine, to the best of our ability, the status and trend of the 
Kittlitz's murrelet at a broad scale, as opposed to the local 
population scale. Therefore, we analyzed trend across multiple 
populations of Kittlitz's murrelet using all of the available 
information on local populations with at least 3 years of at-sea survey 
data and developed a population model that also incorporated 
information on reproduction and survival; these two efforts to assess 
the status and trend of Kittlitz's murrelet across multiple populations 
are also summarized below.

Local Populations

    Only 7 areas have been surveyed for Kittlitz's murrelets at sea in 
a somewhat consistent manner in 3 or more different years between 1989 
and 2012: Glacier Bay (13 surveys of 3 different designs between 1991 
and 2012), Malaspina Forelands (4 surveys of one continuous transect, 
1992-2009), Icy Bay (2002-2012), Prince William Sound (13 years, 1972 
and 1989-2012, with a different design in 1972), Kenai Fjords (3 years, 
2006-2008), Kachemak Bay (4 years, 2005-2011), and Lower Cook Inlet (5 
years, 1993-1999 using two different designs). Few surveys were 
conducted prior to 2000, and the reliability of some of those survey 
data is compromised due to the methodological challenges presented 
above. Therefore, rates of change in local population size in the few 
areas where early surveys were completed (i.e., Glacier Bay, Malaspina 
Forelands, Prince William Sound, and Lower Cook Inlet) often rely 
heavily on 1-2 historical years of data.
    Glacier Bay (37 percent of rangewide population estimate). Three 
different research teams have conducted systematic at-sea surveys for 
marine birds in Glacier Bay and all have employed their own survey 
design and protocol (Kirchhoff 2011, p. 78). Piatt et al. (2011, p.71) 
conducted surveys in 1991, 1999-2003, and 2008 and reported a local 
population decline of 89 percent (negative 10.7 percent per year) over 
this time period, but the decline was not statistically significant due 
to high inter- and intra-annual variance. During the 1991 surveys, a 
different sampling design was used that did not sample the offshore 
habitat randomly nor systematically, raising concern that the 1991 
survey results were not comparable to data collected in 1999-2008 (Drew 
and Piatt 2008, p. 179; Day 2011, p. 39; Kirchhoff 2011, p. 78). 
However, the authors believed that they had adequately addressed 
discrepancies between the two designs in their analysis and that 
Kittlitz's murrelets, in fact, did decline in Glacier Bay between 1991 
and 2008, although the decline appeared to level off after 2002 (Piatt 
et al. 2011, p. 72). Further, Drew and Piatt (2008, p. 178) tested for 
potential survey-based bias in both sampling designs by using spatially 
matched transects and concluded that the Kittlitz's murrelet population 
in Glacier Bay had declined by 83 percent between 1991 and 2000. During 
a similar time period, Lindell (2005, p. 5) conducted surveys in 1993 
in Glacier Bay that were replicated in 2009 and 2010 (Kirchhoff et al. 
2013, p. 6). When analyzed collectively with survey results completed 
by Piatt et al. (2011, p. 7), the annual rate of change was negative 
2.3 percent between 1991 and 2010 and was not statistically significant 
(Kirchhoff et al. 2013, p. 10). Most recently, Hoekman et al. (2011, p. 
35; 2013, p. 15) developed and tested a new, sophisticated survey 
design and protocol specifically for Kittlitz's murrelets in Glacier 
Bay and completed annual surveys accordingly in 2010-2012; this 
protocol currently is under review. The field and analytical techniques 
employed by Hoekman et al. (2013, p. 15) have resulted in much larger 
population estimates (2-3 times greater) of Kittlitz's murrelet 
compared to the more standard approaches used by other researchers 
(Lindell 2005, p. 5; Piatt et al. 2011, p. 71; Kirchhoff et al. 2013, 
p. 6). There is notable disagreement among researchers about the 
current population size and trend of Kittlitz's murrelets in Glacier 
Bay, with the disagreement about trends primarily

[[Page 61774]]

due to differences in survey design and protocol of the 1991 survey.
    Malaspina Forelands (less than 1 percent of rangewide population 
estimate). The Malaspina Forelands, an area extending between Manby 
Point near Yakutat and Point Riou at the entrance to Icy Bay, was 
surveyed initially in 1992 by paralleling the coastline roughly 0.6 mi 
(1 km) offshore for 51 mi (82 km) (Kozie 1993, pp. 1-2). Kissling et 
al. (2011, p. 4) repeated this survey in 2002, 2008, and 2009. Results 
of these surveys are useful to document distribution and qualitative 
rates of change, but the survey design of one linear transect lacks 
rigor and does not lend itself to estimation of population size or 
trend at the scale of a study area. In the four surveys, however, the 
number of Kittlitz's murrelets varied dramatically ranging from 641 in 
1992 to 10 (2002), 39 (2008) and 165 (2009) (Kissling et al. 2011, p. 
7).
    Icy Bay (3 percent of rangewide population estimate). Since 2002, 
eight at-sea surveys for marine birds targeting Kittlitz's murrelet and 
using the same study design and sampling methods have been conducted in 
Icy Bay (2002, 2005, 2007-2012; Kissling et al. 2011, p. 7; Kissling, 
unpublished data). Between 2002 and 2012, the annual rate of change of 
the local population was estimated to be negative 10.0 percent; this 
rate of decline was statistically significant (slope estimate=negative 
0.10 [SE=0.03]) (Kissling, unpublished data). A population model that 
incorporates demographic characteristics including reproduction, 
survival, and abundance of Kittlitz's murrelets in Icy Bay 
substantiated the results of the at-sea surveys by indicating an 8 
percent decline annually between 2002 and 2012, but the variance 
surrounding this estimate is large (Kissling, unpublished data).
    Prince William Sound (4 percent of rangewide population estimate). 
While Prince William Sound has the longest history of survey effort (13 
years), it is also subject to reliability concerns related to 
historical data, especially in regards to varying proportions of 
unidentified Brachyramphus murrelets, as well as impacts of the Exxon 
Valdez oil spill that occurred in March 1989. Several authors 
determined that there had been declines in some marine bird 
populations, including Brachyramphus murrelets, before the spill 
occurred (Klosiewski and Laing 1994, p. 28; Agler et al. 1999, p. 101). 
Kuletz et al. (2011a, p. 103) reported a decline in Kittlitz's 
murrelets in Prince William Sound of 18.1 percent per year between 1972 
and 2007. However, interpretation of population trend in this area was 
complicated by three primary concerns: (1) The 1972 survey used a 
different survey design than the 1989-2012 surveys; (2) the 1972 survey 
was temporally removed from the remainder of the surveys (17 years 
between the 1972 survey and the next survey in 1989); and (3) the 
earlier surveys in 1989-1991 and 1993 had high proportions of 
unidentified murrelets (39-89 percent). Kuletz et al. (2011a, pp. 99-
101) developed a population model that included the unidentified 
murrelets to overcome these challenges and tested the sensitivity of 
the model to inclusion and exclusion of the problematic years; after 
acknowledging the many assumptions and limitations of the analysis, the 
authors found negative trends for populations of Kittlitz's murrelets 
in Prince William Sound regardless of which years were included (p. 
104). In fact, even after removing the 1972 survey, the annual rate of 
population change of Kittlitz's murrelets was greater (negative 30.0 
percent; Kuletz et al. 2011a, p. 103).
    Hodges and Kirchhoff (2012, pp. 118-119), however, postulated that 
misidentification of murrelets in 1989 and 1993 was probable. Based on 
a reanalysis excluding those years and including 2 additional survey 
years (2001 and 2009; not included by Kuletz et al. (2011a, p. 101) 
because only select fjords within Prince William Sound representing 
different statistical populations of murrelets were surveyed in these 
years), Hodges and Kirchhoff (2012, p. 119) concluded that population 
trend of Kittlitz's murrelet in Prince William Sound between 1989 and 
2009 was not significantly different from a stable population. Kuletz 
et al. (2013, pp. 69-71) disputed the case presented by Hodges and 
Kirchhoff (2012, pp. 118-119), contending that the authors erred in 
their assumption of Kittlitz's murrelet distribution, and in including 
the 2001 and 2009 survey data, concluding that there was in fact a 
decline in the Kittlitz's murrelet in Prince William Sound between 1989 
and 2007.
    Cushing et al. (2013, p. 1) took a different approach to address 
the high and varying proportions of unidentified and possibly 
misidentified murrelets by simply reporting populations trends of 
Brachyramphus murrelets (genus level) in Prince William Sound between 
1989 and 2012. There was strong evidence of an overall decline in 
abundance of murrelets with a mean annual rate of change of negative 
5.2 percent or a 70.8 percent cumulative decrease in abundance of 
Brachyramphus murrelets over the 23-year period. This estimate of 
decline applies to both Kittlitz's and marbled murrelets, however, so 
it is difficult to draw firm conclusions about the status of Kittlitz's 
murrelets in Prince William Sound from this analysis. Kuletz et al. 
(2013, pp. 69-71) argued that, given the undisputed decline in 
Brachyramphus murrelets in Prince William Sound, the proportion of 
identified Kittlitz's murrelets to marbled murrelets should have 
increased if the Kittlitz's murrelet population was stable, but instead 
the proportion of identified Kittlitz's murrelets has declined between 
1989 and 2012. However, this argument hinges on comparable 
identification rates of both murrelet species within and among years.
    Kenai Fjords (2 percent of rangewide population estimate). Seven 
surveys using five different survey designs or protocols have been 
conducted in Kenai Fjords, prohibiting reliable estimation of local 
population trends of Kittlitz's murrelet. Arimitsu et al. (2011, p. 17) 
summarized earlier survey efforts for marine birds in the greater Kenai 
Fjords area (1976, 1986, 1989, 2002), most of which concentrated survey 
effort along the shoreline and did not follow a consistent survey 
protocol with previous surveys. Acknowledging many methodological 
issues associated with these surveys, density estimates of Kittlitz's 
murrelet increased by 55 percent between 1986 and 1989 and decreased by 
90 percent between 1989 and 2002 (Arimitsu et al. 2011, p. 18). In 
2006-2008, annual surveys for Kittlitz's murrelets were conducted while 
following a systematic study design and sampling protocol similar to 
those employed in other areas, but with only 3 years of data over a 
short time frame, Arimistu et al. (2011, p. 17) appropriately refrained 
from estimating local population trend and instead assessed variability 
of the Kittlitz's murrelet population during the 3-year period.
    Lower Cook Inlet and Kachemak Bay (9 percent of rangewide 
population estimate). Of all areas with multiple years of surveys, 
Lower Cook Inlet and adjacent Kachemak Bay in the southeastern part of 
the inlet, are the most complex and confounding. In June 1993, Agler et 
al. (1998, pp. 255-256) completed a comprehensive, systematic survey 
for marine birds and mammals covering all of Lower Cook Inlet. A 
portion (roughly one-third) of this area was surveyed in July and 
August 1996-1999, but while using a different systematic sampling 
design (described in Kuletz et al. 2011b, p. 86). Kuletz et al. (2011b, 
p. 86) reanalyzed data from a `core area' of Cook Inlet that had been

[[Page 61775]]

covered during both earlier survey efforts. Within the core area, 
numbers of Kittlitz's murrelet declined significantly by 26.2 percent 
per annum between 1993 and 1999, a total decline of 84 percent over the 
7-year period (Kuletz et al. 2011b, p. 91); however, there are two 
primary concerns related to these surveys. First, in 1993, 82 percent 
of the murrelets observed were not identified to species (Kuletz et al. 
2011b, p. 91), and second, the timing of the four surveys varied 
dramatically, especially between the 1993 survey (7-23 June) and the 
1996-1999 surveys (14 July-16 August; p. 87), severely reducing the 
comparability of these surveys across years. Removing the 1993 survey 
from the trend analysis, numbers of Kittlitz's murrelet declined by 32 
percent annually between 1996 and 1999 in the core area (Kuletz et al. 
2011b, p. 91), although these surveys started and ended later each 
consecutive year (p. 87). These results may be questionable, however, 
given recent information that Kittlitz's murrelets from other parts of 
the northern Gulf of Alaska are known to move into Lower Cook Inlet in 
the post-breeding season (late July-August; Madison et al. 2012, p. 1).
    Similarly, several late-summer surveys of varying sampling designs 
and protocols were conducted between 1988 and 2011 in Kachemak Bay 
(Kuletz et al. 2011b, p. 90; Kuletz, unpublished data), but many of 
these survey efforts lacked a rigorous or systematic survey design, and 
there are concerns about the timing of the surveys. Therefore it is 
difficult to draw statistical inference from their results. Between 
2005 and 2007, systematic surveys of Kachemak Bay were conducted from 
18 to 26 July using standard protocols (Kuletz et al. 2011b, p. 90), 
resulting in annual local population estimates ranging from 1068 to 
3287 Kittlitz's murrelets, depending on the year. Based on these 
surveys, as well as the historical efforts, Kuletz et al. (2011b, p. 
93) concluded that the population of Kittlitz's murrelet in Kachemak 
Bay was statistically stable. In 2011, the same systematic survey of 
Kachemak Bay was repeated, resulting in a considerably lower estimated 
population size of Kittlitz's murrelet (424 birds) than the previous 3 
surveys completed in 2005-2007 (Kuletz, unpublished data). However, we 
cannot draw reliable conclusions from these data for two reasons. 
First, the variance associated with these local population estimates is 
too high to detect a trend between 2005 and 2011 (coefficient of 
variation [a measure of variability in the data]=52-86 percent) (Kuletz 
et al. 2011b, p. 96; Kuletz, unpublished data). Second, the rate of 
change in population size was not linear across the 6-year period and 
the range in estimates (424 to 3,287 Kittlitz's murrelets) cannot be 
demographically explained (Kuletz et al. 2011b, p. 96; Kuletz, 
unpublished data).

Multiple Populations

    Trend analysis. We assessed change in Kittlitz's murrelet 
populations at a broad scale by conducting a comprehensive trend 
analysis that used survey data collected at multiple individual study 
sites (hereafter referred to as the multiple-populations trend 
analysis) (Lukacs and Kissling 2013, p. 27). We limited our analysis to 
those areas with at least 3 different years of survey data, and within 
a study area, we only grouped surveys that sampled similar statistical 
populations; no datasets were combined. We included 9 statistically-
independent populations with datasets spanning from 1989 to 2012 in the 
multiple-populations trend analysis: Glacier Bay-A (1991, 1999-2003, 
2008) (Piatt et al. 2011, p. 70), Glacier Bay-B (1993, 2009-2010) 
(Lindell 2005, p. 5; Kirchhoff et al. 2012, pp. 6, 10), Glacier Bay-C 
(2010-2012) (Hoekman et al. 2013, p. 15), Malaspina Forelands (1992, 
2002, 2008-2009) (Kissling et al. 2011, p. 7), Icy Bay (2002, 2005, 
2007-2012) (Kissling et al. 2011, p. 7; Kissling, unpublished data), 
Prince William Sound (1989-1991, 1993, 1996, 1998, 2000, 2004-2005, 
2007, 2010, 2012) (Cushing, unpublished data), Kenai Fjords (2006, 
2007, 2008) (Arimitsu et al. 2011, p. 18), Kachemak Bay (2005-2007, 
2011) (Kuletz et al. 2011b, p. 96; Kuletz, unpublished data), and Lower 
Cook Inlet (1993, 1996-1999) (Kuletz et al. 2011b, p. 96).
    We considered four model forms to describe and estimate population 
trend of Kittlitz's murrelets across multiple local populations between 
1989 and 2012: constant (no change over time), linear (straight line), 
quadratic (line that displays concavity with a single bend either 
upward or downward), and linear with a change in slope (statistically 
referred to as a `knot') at 2000 (Lukacs and Kissling, p.27). We tested 
the last model form (linear with a knot at 2000) because around this 
time climate regime shifts occurred in the northern Gulf of Alaska 
(1998-1999) and in the Arctic (2000) (Litzow 2006, p. 1386; Overland et 
al. 2008, p. 92) (see Factor A below for more detailed discussion on 
climate regime shifts) and researchers reported that Kittlitz's 
murrelet numbers may have stabilized in some areas shortly thereafter 
(Kuletz et al. 2011a, p. 105; Piatt et al. 2011, p. 73). Of the four 
model forms considered in the multiple-populations trend analysis, the 
linear model form with a knot at 2000 was the most strongly supported 
model (delta Akaike Information Criterion [AIC]=19.2 units; AIC is a 
measure of the relative quality of a statistical model for a given set 
of data and contending model forms; a small delta AIC [e.g., less than 
2] indicates model uncertainty).
    Results of the multiple-populations trend analysis demonstrated 
that the population of Kittlitz's murrelet declined significantly by 
30.6 percent per annum between 1989 and 2000 (slope estimate=negative 
0.31 [SE=0.09]), at which time a statistically significant change in 
the rate of change occurred and populations stabilized between 2000 and 
2012 (slope estimate=0.38 [SE=0.13]; this slope estimate represents the 
positive change from negative 0.31, or a positive slope of 0.07). We 
then removed 3 problematic years of data due to high proportions of 
unidentified murrelets (1993 in Prince William Sound and 1993 in Lower 
Cook Inlet) and to differences in study design (1991 in Glacier Bay) 
and reran the analysis. Although model fit with the problematic data 
points removed gave a poorer fit (delta AIC=12.2), the same model 
(linear with a knot at 2000) was selected and estimated similar trends 
across all populations between 1989 and 2000 (slope estimate=negative 
0.30 [SE=0.10] and between 2000 and 2012 (slope estimate=0.38 
[SE=0.14]. We conclude from this analysis that Kittlitz's murrelets 
declined by roughly 30 percent per annum on average across multiple 
populations between 1989 and 2000, after which abundance stabilized. 
For comparison, the same analysis for the population of marbled 
murrelet across multiple populations indicated a stable trend from 1989 
to 2012 with no change in slope at year 2000; the constant model for 
marbled murrelet was selected as the best model (delta AIC=3.3) when we 
ran the analysis with and without the three questionable data points.
    For assessing status of the Kittlitz's murrelet across their range, 
we found that the multiple-populations trend analysis described above 
is more useful and rigorous than trend estimates of individual local 
populations; however, several drawbacks to our approach exist. First, 
the trend analysis included populations of Kittlitz's murrelets only 
from Glacier Bay in the south to Lower Cook Inlet in the north, an area 
that contains most of the known larger populations of the Kittlitz's 
murrelet (see Local Populations, above), but covers a small portion of 
their overall

[[Page 61776]]

range. Second, we only considered linear and quadratic shapes to the 
trend of multiple populations combined. Third, demographic parameters 
such as reproduction and survival are not considered in the trend 
analysis, even though these vital rates drive current and future 
abundance. Fourth, the trend analysis does not allow population 
projections into the future or estimation of extinction probabilities. 
To address some of these drawbacks, we developed a population model as 
a tool to assessing population status of the Kittlitz's murrelet at a 
broad scale.
    Population model. Owing to the limitations of the multiple-
populations trend analysis, we developed a population model to help 
evaluate the status of the Kittlitz's murrelet across all populations 
with sufficient demographic information (hereafter referred to as the 
multiple-populations model) (Brooks et al. 2004, p. 515; Johnson et al. 
2010, p. 1084; Lukacs and Kissling 2013, p. 5). Population models are a 
well-established tool for evaluating population dynamics for species 
with limited and variable datasets, such as the Kittlitz's murrelet, by 
linking population size with stage-specific vital rates. A single 
comprehensive population model like the one we developed integrates all 
of the available data on abundance, survival, and reproduction; shares 
information from data-rich areas with data-poor areas; and predicts 
population size given the demographic data each year and into the 
future. One advantage to using this approach for the Kittlitz's 
murrelet is that it allowed us to include data on reproduction at 
Agattu and Kodiak islands and Icy Bay (see Nesting and Reproductive 
Performance, above) and on survival from Icy Bay (see Survival, above), 
thereby nearly doubling the spatial scope of inference compared to that 
of the multiple-populations trend analysis. Another advantage is that 
it is not purely a statistical test such as the multiple-populations 
trend analysis, but instead incorporates aspects of the biology of the 
Kittlitz's murrelet.
    We included 7 local populations in the multiple-populations model: 
Glacier Bay, Icy Bay, Prince William Sound, Kenai Fjords, Kachemak Bay, 
Kodiak Island, and Agattu Island. In Glacier Bay, where multiple 
datasets on abundance exist, we used the dataset (Glacier Bay-A) with 
the most number of years of abundance estimates (Piatt et al. 2011, p. 
70). We modeled data collected from 2000 to 2012 because only abundance 
was available prior to 2000, and without concurrent data on 
reproduction or survival, we were unable to achieve a good model fit 
(Lukacs and Kissling 2013, p. 6). Because our primary interest was to 
determine the current and future status and population dynamics of the 
Kittlitz's murrelet at a broad scale and few demographic data were 
collected prior to 2000, we did not consider the exclusion of pre-2000 
data to be a major constraint to the model development or results. 
Reproduction was estimated as the product of breeding propensity (the 
proportion of birds attempting to nest in a given year) and nesting 
success. Following Peery and Henry (2010, p. 2417), we considered a 
range of values for breeding propensity (low=0.181, medium=0.526, 
high=0.817; see Reproductive Performance, above, for details) 
(Kissling, unpublished data) and estimated daily nest survival at 
Agattu and Kodiak islands (0.968) (Kaler, unpublished data; Lawonn, 
Oregon State University, 2008-2011, unpublished data) and Icy Bay 
(0.979) (Kissling, unpublished data). For areas without nesting 
information, we applied the estimate of nesting success from the study 
site most similar in landscape (e.g., glacial, non-glacial). We 
considered a range of values for annual adult survival (low=0.79, 
medium=0.89, high=0.95) (Kissling, unpublished data) and used a 
proportion (0.70) of adult survival as juvenile survival following 
Peery and Henry (2010, p. 2415) and others (McShane et al. 2004, p. 3-
41; Piatt et al. 2007, p. 58).
    The best-fit model for the multiple-populations model included the 
medium-level breeding propensity (0.526) and medium-level annual 
survival (0.89) and predicted an annual rate of change in multiple 
populations to be negative 1.7 percent but with large variance that 
included both a stable population and a quasi-extinction scenario 
(Lukacs and Kissling 2013, p. 10). The probability of extinction, with 
a quasi-extinction threshold defined for the purposes of this modeling 
exercise as less than 100 individuals per population, at 2032 (i.e., 20 
years from present) was zero and at 2037 (i.e., 25 years from present) 
was less than 0.01 (Lukacs and Kissling 2013, p. 10; Lukacs, University 
of Montana, unpublished data). We were unable to model population size 
accurately or precisely beyond 25 years into the future because the 
variance increased rapidly and the model became unstable. Given the 
paucity of data available for the Kittlitz's murrelet, predicting 
future population size is challenging for any number of years and 
becomes more difficult with increased time, but after examining model 
fit and diagnostics, we determined that model predictions of population 
size of this species between 2000 and 2037 were informative in our 
assessment of the current and future status of this species.
    As with all modeling exercises, there are numerous limitations and 
assumptions related to model structure and inputs that need to be met 
or evaluated to assess reliability and usefulness of the model results. 
Key assumptions for this type of modeling (not a comprehensive list) 
include: (1) The model structure accurately represented Kittlitz's 
murrelet population biology; (2) populations were sampled 
independently; (3) populations are not under density-dependent 
regulation; (4) estimates of reproduction and survival were 
appropriately applied to and representative of populations lacking 
those data; (5) the populations for which sufficient data exist to 
include in the model were representative of all Kittlitz's murrelet 
populations; (6) immigration and emigration rates within a population 
were equal; and (7) estimates of vital rates and their associated 
variances between 2000 and 2012 that were used in the model to predict 
future population size will be comparable on average to those 
experienced by Kittlitz's murrelets between the present time and 2037. 
These are reasonable assumptions to make for the purposes of this 
modeling exercise in the absence of more complete data on the 
Kittlitz's murrelet or a similar species that would allow explicit 
testing of each assumption.
    We acknowledge that the available information on the demography of 
the Kittlitz's murrelet is both spatially and temporally limited and 
therefore, attempted to account for these data limitations in the 
multiple-populations model in three ways. First, we chose to use a type 
of model (Bayesian Integrated Population Model) that is specifically 
aimed to serve as a powerful statistical tool for evaluating the 
dynamics of populations with messy or incomplete datasets (Brooks et 
al. 2004, p. 515; Johnson et al. 2010, p. 1084). Second, we considered 
a range of values for key demographic parameters such as breeding 
propensity and adult survival, placing weight on empirical data derived 
from that population and reducing weight for data borrowed from a 
different population. This approach allowed the empirical data 
available for a specific population to have a strong influence on the 
model results for that population. Third, we drew on previous 
population modeling efforts for the congeneric marbled murrelet, 
recognizing that all of these efforts, including our effort for the 
Kittlitz's

[[Page 61777]]

murrelet, had different objectives and therefore used a different type 
of population model (Beissinger 1995, pp. 385-393; McShane et al. 2004, 
pp. 3-27-3-58; Piatt et al. 2007, pp. 54-67; Peery and Henry 2010, pp. 
2414-2424). We also used the marbled murrelet as a proxy for some 
unknown or less-defined demographic parameters of the Kittlitz's 
murrelet. We recognize all of these limitations and assumptions of the 
multiple-populations model and believe that the high variance 
associated with most of the model input parameters and the results 
accurately reflects our current state of knowledge of the status of the 
Kittlitz's murrelet at a broad scale.

Summary of Population Status and Trends

    We estimate the minimum rangewide population of Kittlitz's murrelet 
to be 33,583 birds (95 percent CI=25,620-41,546). In evaluating 
population status and trends of the Kittlitz's murrelet, we 
collectively considered all of the available information across all 
time periods, at the local population scale, and at a broad scale 
across multiple populations. We determined that some local populations 
of the Kittlitz's murrelet may have declined at some point over the 
last few decades (e.g., Glacier Bay, Prince William Sound, Lower Cook 
Inlet) and some may still be in decline (e.g., Icy Bay, Kachemak Bay). 
Across all populations, we conclude that there was a decline of 
approximately 30 percent per annum in Kittlitz's murrelets between 1989 
and 2000, but since then populations appear to have stabilized or, when 
coupled with information on reproduction and survival, may be declining 
and are projected to continue to decline at a much slower rate.

Summary of Information Pertaining to the Five Factors

    Section 4 of the Act (16 U.S.C. 1533) and implementing regulations 
(50 CFR 424) set forth procedures for adding species to, removing 
species from, or reclassifying species on the Federal Lists of 
Endangered and Threatened Wildlife and Plants. Under section 4(a)(1) of 
the Act, a species may be determined to be endangered or threatened 
based on any of the following five factors:
    (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range;
    (B) Overutilization for commercial, recreational, scientific, or 
educational purposes;
    (C) Disease or predation;
    (D) The inadequacy of existing regulatory mechanisms; or
    (E) Other natural or manmade factors affecting its continued 
existence.
    In making this finding, information pertaining to the Kittlitz's 
murrelet in relation to the five factors provided in section 4(a)(1) of 
the Act is discussed below. In considering what factors might 
constitute threats, we must look beyond the mere exposure of the 
species to the factor to determine whether the species responds to the 
factor in a way that causes actual impacts to the species. If there is 
exposure to a factor, but no response, or only a positive response, 
that factor is not a threat. If there is exposure and the species 
responds negatively, the factor may be a threat and we then attempt to 
determine how significant a threat it is. If the threat is significant, 
it may drive or contribute to the risk of extinction of the species 
such that the species warrants listing as endangered or threatened as 
those terms are defined by the Act. This does not necessarily require 
empirical proof of a threat. The combination of exposure and some 
corroborating evidence of how the species is likely impacted could 
suffice. The mere identification of factors that could impact a species 
negatively is not sufficient to compel a finding that listing is 
appropriate; we require evidence that these factors are operative 
threats that act on the species to the point that the species meets the 
definition of an endangered or threatened species under the Act.
    In making our 12-month finding on the petition we considered and 
evaluated the best available scientific and commercial information.

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

    The Kittlitz's murrelet is primarily a subarctic species with a 
broad distribution that encompasses a diversity of marine and 
terrestrial habitats along most of coastal Alaska and eastern Russia. 
This species exhibits variable habitat affinities throughout its range 
and its annual cycle, which makes it difficult to identify necessary 
habitats and potential threats to those habitats. For example, in the 
breeding season, the greatest densities of Kittlitz's murrelet 
typically are observed in glacially-influenced marine waters of south-
coastal Alaska (Kuletz et al. 2003b, p. 136; Arimitsu et al. 2011, p. 
18; Kissling et al. 2011, p. 7; Kuletz et al. 2011a, pp. 102-103; 
Kuletz et al. 2011b, pp. 90-92; Piatt et al. 2011, p. 70). There are a 
handful of glaciated areas in southeastern Alaska, such as Le Conte, 
Thomas, Dundas, and Taylor bays, where no Kittlitz's murrelets have 
been observed in the breeding season in recent years, although several 
individuals were collected historically in Le Conte Bay (Kissling et 
al. 2011, pp. 7, 9). Lower densities of this species also occur in non-
glaciated marine waters of the Alaska Peninsula, Aleutian Islands 
(Madison et al. 2011, pp. 118-119), western and northern Alaska (Day et 
al. 2011, pp. 58-59) and Russia (Artukhin et al. 2011, pp. 26-30). Low 
numbers of Kittlitz's murrelet also have been observed annually during 
the breeding season on freshwater lakes in southwestern Alaska (Savage 
2013, in litt.; Walsh 2013, in litt.). In the non-breeding season, 
Kittlitz's murrelets migrate to the Bering and Chukchi seas where they 
occupy offshore marine waters, or occur in polynyas or in open water 
leads within the sea ice (Madison et al. 2012, p. 1; Kuletz, 
unpublished data), but they also are observed in ice-free waters of the 
northern Gulf of Alaska during this period (Day et al. 1999, pp. 4-5; 
Kuletz, unpublished data). The reason for the apparent, but irregular, 
association with sea ice or glacial ice during specific periods in the 
annual cycle is not clear, nor is it known if it is biologically 
meaningful or is simply a proxy for an unidentified habitat feature of 
importance (Arimitsu et al. 2012, p. 18). Furthermore, it is not known 
whether the explanatory factor(s) occur in the marine or terrestrial 
habitat of the Kittlitz's murrelet, or both.
    Without an understanding of the habitat requirements of the 
Kittlitz's murrelet, we identified, deconstructed, and assessed 
possible threats to the marine and terrestrial habitats currently used 
by this species. We then evaluated potential impacts by considering the 
exposure and response of Kittlitz's murrelet at the individual level 
and population level to each possible threat. Because the underlying 
mechanisms driving habitat use of the Kittlitz's murrelet are not 
defined, we attempted to establish links between possible threats to 
marine and terrestrial habitats and demographic change of Kittlitz's 
murrelet at the population level. Our analysis focused on possible 
threats to habitats occupied by Kittlitz's murrelets in the summer 
months because this was the time period for which the most data were 
available, along with the greatest number of possible identified 
threats and demographic bottlenecks (e.g., poor reproduction; see 
Reproductive Performance, above). We considered potential threats 
during the non-breeding period if sufficient information was available. 
Under Factor A, we considered climate change and

[[Page 61778]]

environmental contaminants as potential threats to the habitats used by 
the Kittlitz's murrelet.
Climate Change
    Our analyses under the Act include consideration of ongoing and 
projected changes in climate. The terms ``climate'' and ``climate 
change'' are defined by the Intergovernmental Panel on Climate Change 
(IPCC). ``Climate'' refers to the mean and variability of different 
types of weather conditions over time, with 30 years being a typical 
period for such measurements, although shorter or longer periods also 
may be used (IPCC 2007, p. 78). The term ``climate change'' thus refers 
to a change in the mean or variability of one or more measures of 
climate (e.g., temperature or precipitation) that persists for an 
extended period, typically decades or longer, whether the change is due 
to natural variability, human activity, or both (IPCC 2007, p. 78). 
Various types of changes in climate can have direct or indirect effects 
on species. These effects may be positive, neutral, or negative, and 
they may change over time, depending on the species and other relevant 
considerations, such as the effects of interactions of climate with 
other variables (e.g., habitat fragmentation) (IPCC 2007, pp. 8-14, 18-
19). Identifying likely effects often involves aspects of climate 
change vulnerability analysis. Vulnerability refers to the degree to 
which a species (or system) is susceptible to, and unable to cope with, 
adverse effects of climate change, including climate variability and 
extremes. Vulnerability is a function of the type, magnitude, and rate 
of climate change and variation to which a species is exposed, its 
sensitivity, and its adaptive capacity (IPCC 2007, p. 89; see also 
Glick et al. 2011, pp. 19-22). There is no single method for conducting 
such analyses that applies to all situations (Glick et al. 2011, p. 3). 
We use our expert judgment and appropriate analytical approaches to 
weigh relevant information, including uncertainty, in our consideration 
of various aspects of climate change.
    Within the range of the Kittlitz's murrelet, climate change is 
occurring and is likely altering marine and terrestrial habitats used 
by this species. In Alaska, average annual Statewide air temperatures 
have increased by nearly 4.0 degrees F between 1949 and 2005, but 
decreased by 2.3 degrees F in the last decade (2000-2010) with most of 
the change occurring over winter (Markon et al. 2012, p. 11; Wendler et 
al. 2012, pp. 111-112). The recent cooling trend suggests a shift from 
the long-term warming trend (Wendler et al. 2012, p. 111), even though 
climate models project warming to continue in Alaska over the next 
century (Markon et al. 2012, pp. 14-21). Precipitation also increased 
over the last few decades, but it is more difficult to quantify (Arendt 
et al. 2009, p. 4132; Markon et al. 2012, p. 12). In addition, 
subsurface and surface waters of the North Pacific Ocean, including the 
Gulf of Alaska, and Bering and Chukchi seas, have warmed over the last 
few decades (Bograd et al. 2005, p. 244; Overland and Wang 2007, p. 
178; Stabeno et al. 2007, pp. 2607-2608; Steele et al. 2008, p. 2; 
Mueter et al. 2009, p. 96; Hazen et al. 2012, p. 2). A significant part 
of the observed warming in Alaska occurred as a sudden, step-like 
change in the mid-1970s, which coincided with a major shift in 
atmospheric circulation patterns across a large portion of the Pacific 
basin, called the Pacific Decadal Oscillation (PDO) (Mantua et al. 
1997, p. 1070). It is likely that some portion of the observed warming 
over the last century and recent cooling in Alaska is attributed to 
inherent decadal-scale variability in regional climate, like the PDO 
(Markon et al. 2012, p. 11; Wendler et al. 2012, p. 113), making it 
difficult to ascertain any amplified or accelerated impacts of natural 
variability or cycles from underlying long-term warming trends in 
Alaska. Regardless, marine and terrestrial habitats of the Kittlitz's 
murrelet are changing in response to climate change, and we anticipate 
that these changes will continue. Available information suggests that 
the changes may affect the Kittlitz's murrelet; however, the specific 
response or sensitivity of the species to these current and forecasted 
changes is uncertain at this time.

Loss of Glaciers

    Loss of glacial volume is a phenomenon occurring on a global scale 
and, during the recent decades, at rates that cannot be explained by 
historical trends alone (Dyurgerov and Meier 2000, pp. 1406, 1410; 
Lemke et al. 2007, pp. 356-359). The primary driver of glacier change 
is climate (Markon et al. 2012, p. 45), especially temperature 
(Oerlemans 2005, p. 677; Arendt et al. 2009, p. 4132). Maritime 
glaciers terminating in tidewater are particularly sensitive to 
temperature change (Berthier et al. 2010, p. 93), including sea surface 
temperatures (Post et al. 2011, p. 306), and therefore have the 
potential to shed ice more rapidly than land-locked glaciers (Markon et 
al. 2012, p. 46). Yet, changes in individual tidewater glaciers are 
dominated by dynamic, complex cycles, with low-order effects occurring 
due to climate (Arendt et al. 2009, p. 4132; Post et al. 2011, p. 306).
    At the beginning of the 20th century, many of Alaska's tidewater 
glaciers began to retreat (Barclay et al. 2006, p. 160) and in less 
than 100 years, major ocean inlets, such as Glacier and Icy bays, were 
formed by glacial recession (Molnia 2008, p. K7). The Kittlitz's 
murrelet presumably adjusted its distribution in order to take 
advantage of these newly-created habitats where they now occur in large 
numbers in the breeding season (Kissling et al. 2011, p. 7; Piatt et 
al. 2011, p. 66). Currently, within the range of the Kittlitz's 
murrelet, 59 major tidewater glaciers exist, all along the southern 
coast of Alaska (Molnia 2008, pp. K57-59), and a few very small 
isolated mountain glaciers or permanent snow occur on the Alaska 
Peninsula, select Aleutian Islands, Koryak Highlands and Kamchatka 
Peninsula (Artukhin et al 2011, p. 31; Arendt et al. 2012). The 
majority (68 percent) of these tidewater glaciers are in retreat, 
grounded (resting on the ocean floor) or at the shoal (shallow water 
area) (Molnia 2008, pp. K57-59). Over the last few decades, glacial ice 
loss has been greatest for the glaciers along the southern coast of 
Alaska compared to the mountain glaciers of central Alaska, Brooks 
Range, and Alaska Peninsula (Larsen et al. 2005, p. 548; Berthier et 
al. 2010, pp. 92-93; Arendt et al. 2009, pp. 4127-4128; Le Bris et al. 
2011, p. 141).
    Approximately 66 percent of the minimum global population of 
Kittlitz's murrelet is associated with glacially affected marine waters 
in the breeding season. Within these areas, Kittlitz's murrelets prefer 
highly stratified, cool, turbid marine waters near tidewater glaciers 
and glacial outflows, especially in the vicinity of submerged marine 
sills where localized upwelling occurs (Day and Nigro 2000, pp. 5, 8; 
Kissling et al. 2007, pp. 2171-2172; Allyn et al. 2012, p. 244; 
Arimitsu et al. 2012, p. 18). The reason that Kittlitz's murrelets use 
these areas is not clear, but several hypotheses have been proposed. 
For example, marine waters with these characteristics may provide 
increased abundance of high-energy forage fish, such as sand lance or 
capelin (Robards et al. 2003, p. 71; Arimitsu et al. 2008, p. 137; 
Arimitsu et al. 2011, pp. 15, 17-18; Renner et al. 2012, pp. 2037-
2038), or promote greater foraging efficiency for Kittlitz's murrelets 
(Day et al. 2003, pp. 695-696; Arimitsu et al. 2011, p. 14; Allyn et 
al. 2012, pp. 244-245). Nutrient-rich glacial meltwater (Crusius et al. 
2011, p. 1) forms a turbid, stratified surface layer that limits light 
penetration, reducing phytoplankton

[[Page 61779]]

growth at depth (Hood et al. 2009, p. 1046; Piwosz et al. 2009, pp. 
552-554, 556) and possibly affecting vertical diel (24 hour) migration 
of zooplankton and fish (Abookire et al. 2002, p. 378; Frank and Widder 
2002, p. 1189). Owing to their proportionately larger-diameter eye 
compared to the marbled murrelet (Day et al. 2003, p. 695), the 
Kittlitz's murrelet may specialize at foraging in these low light 
conditions, taking advantage of underutilized ocean space and prey. In 
the northern Gulf of Alaska, freshwater streams and rivers fed by 
glaciers and snow melt drain into the coastal ocean and create large 
plumes of highly turbid water (Crusius et al. 2011, pp. 1-2), where 
both zooplankton and juvenile fish abundance is greater compared to 
outside the plumes (McFadden et al. 2012, p. 1). Juvenile fish may 
occupy these areas to take advantage of concentrated zooplankton 
populations or to evade predation (McFadden et al. 2012, p. 1). Several 
studies have also suggested that the physical features and landforms 
(e.g., underwater sills and moraines) within glacial fjords interact 
with tides to concentrate prey of the Kittlitz's murrelet (Kissling et 
al. 2007, p. 2171; Allyn et al. 2012, pp. 244-245; Arimitsu et al. 
2012, pp. 10-15). Yet no studies have reported greater foraging 
success, or subsequent productivity or survival, in glacially affected 
waters compared to those without glacial influence, or in fjord versus 
non-fjord habitats (e.g., outer coast of the Gulf of Alaska).
    Any foraging advantages in glacially affected waters should be 
readily apparent in the breeding season when Kittlitz's murrelets 
concentrate in these areas and deliver whole fish singly to chicks at 
nests. However, nests have been found throughout this species' range, 
including many areas without tidewater glaciers or glacially influenced 
marine waters (e.g., Kodiak and Aleutian islands, northern Alaska, and 
Russia), and, although highly variable, chick meal delivery rates at 
nests monitored at glacial sites (Naslund et al. 1994, p. 46; Kissling, 
unpublished data) are not substantially different from those at non-
glacial sites (Lawonn 2012, pp. 27-28, 55; Kaler, unpublished data), 
with one exception. Delivery rates for Agattu Island are much higher 
than those for all other sites, but the lack of glacial influence in 
the marine system alone cannot explain the unusually high rate of 10.2 
fish per day, especially when compared to the moderate rate of 6.3 fish 
per day at nearby Adak Island (Kaler, unpublished data). Agattu Island 
is the only study site where rockfish and Pacific cod, low-energy-
density fishes (Anthony et al. 2000, p. 75), have been delivered as 
chick meals at monitored nests (Kaler, unpublished data), likely 
explaining the higher delivery rates and lower fledging mass of chicks. 
However, there is no information to suggest that the absence of high-
quality fishes in the chick diet of Kittlitz's murrelets on Agattu 
Island is associated with the absence of glaciers in this region. On 
nearby Buldir Island in the western Aleutians, chick diets of tufted 
puffin (Fratercula cirrhata) and horned puffin (F. corniculata) between 
1988 and 2012 were consistently composed of low-quality fish (i.e., 
hexagrammids) with intermittent years of relatively high percentages of 
high-quality Pacific sand lance (Warzybok et al. 2013, pp. 162, 180). 
Therefore, although poor quality forage fish may be affecting nesting 
success of Kittlitz's murrelets on Agattu Island, it appears to be 
related to natural and regional fluctuations in forage fish abundance 
that cannot be attributed to the lack of glacial influence. Similarly, 
on non-glaciated Kodiak Island, the chick meal delivery rate (4.6 fish 
per day) is comparable to that estimated at glaciated sites (3-5 fish 
per day) (Naslund et al. 1994, p. 46; Kissling, unpublished data). It 
is possible, but extremely unlikely, that Kittlitz's murrelets nesting 
on Kodiak Island make the lengthy round-trip flight to forage in the 
glacially-affected waters of Kenai Fjords (488 mi round-trip [784 km]), 
Kachemak Bay (374 mi [602 km]), Lower Cook Inlet (250 mi [402 km]), or 
perhaps to the far less-glaciated waters of the Alaska Peninsula (31 mi 
[50 km]) and then return to their nests with fish. For all of these 
reasons, we cannot determine whether glacially affected waters are a 
required or advantageous (in terms of fitness) element of breeding 
habitat for the Kittlitz's murrelet.
    In addition to chick diet, trophic level and stomach contents of 
adult Kittlitz's murrelets sampled in the breeding season did not 
differ between glaciated and non-glaciated areas (Day et al. 1999, p. 
9). In glacial fjords of southeastern Alaska, adult Kittlitz's 
murrelets captured in the early breeding season (May) were heavier 
compared to those captured in the late breeding season (late July-
August) (Kissling, unpublished data). Reduced body mass of Kittlitz's 
murrelets during the breeding season may be aimed at increasing flight 
efficiency and reducing energetic costs of transiting to and from nest 
sites (Hatch 2011, p. 82), but too few murrelets appear to attempt to 
breed annually (18 percent; see Reproductive Performance, above) 
(Kissling, unpublished data) to explain the overall change in body mass 
between early and late breeding periods. Furthermore, the rapid 
departure from breeding sites (Robards et al. 2003, pp. 92, 100, 104; 
Kissling et al. 2007, pp. 2167-2168; Madison et al. 2012, p. 1) suggest 
that the foraging conditions and resources in glacially-affected waters 
are suitable and sufficient for breeding only for a short period. 
Otherwise, it is reasonable to assume that murrelets would remain in 
the area to take advantage of locally abundant and available food prior 
to fall migration. Available information at this time does not suggest 
that foraging conditions in glacially affected waters are superior to 
those in marine waters without glacial influence. However, we do not 
conclude that a change in such conditions would lead to a population- 
or species-level effect on the Kittlitz's murrelet.
    Another reason that the Kittlitz's murrelet occurs 
disproportionately in glacially influenced areas in the breeding season 
may be because they are seeking suitable nesting habitat on 
historically-glaciated scree slopes or on cliff and rock ledges of 
glacial cirques (steep, bowl-shaped hollow at the head of a mountain 
valley) or nunataks (Day et al. 1999, pp. 13, 25-26; Piatt et al. 1999, 
pp. 8, 12; Kissling, unpublished data). Because this species nests on 
the ground and chicks are mostly left unattended for 24-31 days except 
for periodic feeding visits by parents (Lawonn 2012, p. 55; Kaler, 
unpublished data; Kissling, unpublished data), these remote, barren, 
unproductive areas are likely selected because terrestrial predators 
are largely absent. The presumably forage-rich marine waters are 
beneficial, but may not be the primary driver concentrating Kittlitz's 
murrelets in these areas in the breeding season; in fact, low numbers 
of Kittlitz's murrelets have been observed regularly on freshwater 
lakes adjacent to mountainous terrain in southwestern Alaska (Savage 
2013, in litt.; Walsh 2013, in litt.), suggesting that perhaps some 
individuals may not require marine waters solely during the breeding 
season. Nelson and Hamer (1995, p. 66) argue that for the marbled 
murrelet, and most likely the Kittlitz's murrelet, strategies to avoid 
predation determine much of their nesting behavior, including nest site 
selection. However, as mentioned above, Kittlitz's murrelets nest 
successfully throughout their range, and there is no conclusive 
evidence to suggest that nest sites near glaciers are safer than those 
not near glaciers.
    Between 2007 and 2012, active nests of Kittlitz's murrelet were 
regularly monitored at three sites ranging from

[[Page 61780]]

heavily glaciated southeastern Alaska (Icy Bay) to the non-glaciated 
Aleutian Islands (Agattu and Adak islands), with Kodiak Island serving 
as a geographic midpoint. Apparent nest success was lowest in the 
Aleutian Islands (19 percent; n=95) (Kaler, unpublished data), followed 
by Kodiak (23 percent; n=71) (Lawonn, unpublished data) and Icy Bay (40 
percent; n=35) (Kissling, unpublished data), but apparent nest success 
may be severely biased because unsuccessful nests are less likely to be 
found than are successful nests (Johnson and Shaffer 1990, p. 595). 
Therefore, we estimated daily nest survival using nest data collected 
at these three sites. We developed 10 a priori candidate models that 
included a combination of study area, year, nest age, nest stage, 
glacial group (Icy Bay=glacial, Kodiak and Agattu islands=non-glacial), 
and genetic group (Icy Bay and Kodiak Island=eastern, Agattu 
Island=western; see Taxonomy and Species Description, above). The best-
fit model included ``glacial group,'' but model fit was poor, and the 
difference in daily nest survival in glacial (0.979  
SE=0.005) and non-glacial (0.968  SE=0.003) sites was not 
statistically significant. This analysis did not specifically address 
nest safety or consider cause of failure, but the results do indicate 
that daily nest survival in glaciated areas is not statistically 
different when compared to non-glaciated areas.
    Not only have nests of the Kittlitz's murrelet been found 
throughout their range, but also suitable nest habitat exists rangewide 
with significant portions available in areas with and without glaciers. 
Barren areas characterized by bare rock, gravel, sand, silt, or clay 
with little or no ``green'' vegetation present are used in greater 
proportion to their availability and appear to be the preferred nesting 
habitat of the Kittlitz's murrelet rangewide, although preferences vary 
regionally and with availability (Kaler et al. 2009, p. 366; Lawonn 
2012, pp. 90, 101-102; Felis, unpublished data; Kissling, unpublished 
data). We mapped nest habitat of the Kittlitz's murrelet rangewide by 
using known nest locations to define regional thresholds and criteria 
for elevation, distance to ocean, slope, and landcover. Despite 
variability in suitability factors, the greatest amount of suitable 
nesting habitat for Kittlitz's murrelets was located in northern Alaska 
(10,538 mi\2\ [27,292 km\2\]; 8.6 percent of total land), followed by 
south-coastal Alaska (9,160 mi\2\ [23,723 km\2\]; 7.8 percent), Alaska 
Peninsula including Kodiak Island (6,004 mi\2\ [15,511 km\2\]; 18.5 
percent) and the Aleutian Islands (1,715 mi\2\ [4,441 km\2\]; 36.8 
percent) (Felis, unpublished data). The results for Russia are not 
comparable to the values presented here because of differences in 
methodology, but it appears that there may be a significant amount of 
suitable nest habitat for Kittlitz's murrelet in Russia (Felis, 
unpublished data). We did not detect a positive relationship between 
the amount of suitable nesting habitat and glacial extent or persistent 
snow. We were unable to estimate future changes in amount of suitable 
nest habitat as a result of climate change because the necessary land 
cover predictions at the appropriate spatial scale do not currently 
exist. We do anticipate primary succession in previously barren, ice- 
and snow-covered areas, as well as northward and elevational shifts in 
forest biomes (Beck et al. 2011, pp. 5-6). In addition, our mapping 
effort of suitable nest habitat did not take into account proximity to 
foraging areas (e.g., submerged marine sill), although we did consider 
distance to the ocean. Nonetheless, given the diversity of habitats 
used by this species for nesting and the seemingly large amounts of 
suitable nest habitat throughout its range, we conclude that the 
Kittlitz's murrelet is not limited by the current amount of suitable 
nest habitat.
    For a short period following glacial retreat, thinning or 
subsequent isostatic rebound (uplift in ground released from the weight 
of glaciers), additional barren, isolated habitat is created that may 
be suitable for nesting Kittlitz's murrelets. However, any habitat 
gained probably lasts only 5-20 years before primary succession ensues, 
provided that the substrate is sufficiently stable, usually beginning 
with dwarf fireweed (Epilobium spp.), Dryas drummondii (a mat-forming 
dwarf shrub), and willow (Salix spp.), followed by alder (Alnus 
sinuata) and then Sitka spruce (Picea sitchensis) (Chapin et al. 1994, 
pp. 149, 151). As plants colonize the landscape, the habitat rapidly 
becomes unsuitable for nesting Kittlitz's murrelets, but does begin to 
support increasingly greater diversity and abundance of other wildlife 
species, such as small mammals and birds, which in turn attracts 
predators. Eventually, previously isolated areas of barren habitat, 
such as nunataks, are accessible to predators through vegetated 
corridors, reducing their suitability for nesting. Consequently, 
distance between suitable nesting and foraging habitat for Kittlitz's 
murrelet is expected to increase, and murrelets will likely need to 
nest at higher elevations where the rate of change in habitat should be 
slower. In contrast, the transition from barren to vegetated habitat in 
deglaciated areas may benefit the marbled murrelet, a species that 
typically nests on the mossy limbs of large trees or on cliff ledges 
surrounded by vegetation (Barbaree 2011, pp. 65, 71-74).
    In Icy Bay, successful nests (n=14) of radio-marked Kittlitz's 
murrelet were located closer to the ocean (median distance=5.6 mi [9.0 
km]) than failed nests (n=21; median distance=15.0 mi [24.1 km]), 
although elevation did not affect nest fate (4,226 ft [1,288 m] and 
4,718 ft [1,435 m], respectively) (Kissling, unpublished data). 
Comparatively, radio-marked marbled murrelets nested (n=13 nests) at 
lower elevations (median elevation=1,368 ft [417 m]) and closer to the 
ocean (median distance=2.9 mi [4.7 km]) than Kittlitz's murrelets 
(4,291 ft [1,308 m] and 8.8 mi [14.2 km], respectively), and exhibited 
both higher breeding propensity and nest success (Kissling, unpublished 
data). These results suggest that in this glaciated area there is an 
advantage to nesting closer to the ocean and at lower elevations, most 
likely due to reduced energetic costs associated with delivering prey 
to chicks and predator avoidance (Hatch 2011, pp. 86-87). Marbled 
murrelets also nested in a greater diversity of habitat types in Icy 
Bay, including barren, shrubland, and conifer sites, compared to 
Kittlitz's murrelets that were restricted to barren sites. Although 
glacial recession and subsequent primary succession will likely reduce 
access to high-quality nesting habitat of the Kittlitz's murrelet in 
part of its range, we do not know that these ecological processes will 
have a population- or species-level impact on the Kittlitz's murrelet 
for two reasons. First, nests of this species have been found 
throughout its range, some in areas with considerable amounts of 
vegetation (e.g., average 51 percent at nest sites in Aleutian Islands) 
(Kaler et al. 2009, p. 366; Kaler and Kenney 2013, pp. 73-74), 
suggesting some level of adaptability to variable terrestrial 
conditions. Second, the Kittlitz's murrelet population has been 
presumably stable since 2000 despite continued loss of glaciers in 
south-coastal Alaska (see Population Status and Trends, above).

Changes in Ocean Conditions

    Ocean temperatures in Alaska have increased (Bograd et al. 2005, p. 
244; Overland and Wang 2007, p. 178; Stabeno et al. 2007, pp. 2607-
2608; Steele et al. 2008, p. 2; Mueter et al. 2009, p. 96) and are 
predicted to continue to increase (IPCC 2007, pp. 45-

[[Page 61781]]

46; Haufler et al. 2010, p. 10; Hazen et al. 2012, p. 2). Consequently, 
physical and biological changes in the marine environment are expected, 
but the scope and magnitude of these are unknown and difficult to 
project. Although we do not expect direct effects to the Kittlitz's 
murrelet, we may observe indirect effects such as changes to their prey 
base, which in turn, would likely affect their survival, reproduction, 
and perhaps distribution.
    The Kittlitz's murrelet appears to be a flexible forager with a 
diet that varies considerably among seasons, but is more specialized 
within a season. For example, nesting Kittlitz's murrelets need high-
energy forage fish to deliver to chicks at nests, requiring access to 
both foraging areas where these prey occur and nesting habitat. 
Generally, however, the diet of the Kittlitz's murrelet ranges from 
mostly zooplankton in the winter months to predominantly fish in the 
summer months, although zooplankton is part of their diet throughout 
the entire annual cycle (Hobson et al. 1994, p. 795; Day et al. 1999, 
p. 9; Hatch 2011, pp. 25-26, 35; Allyn 2012, p. 102). A comprehensive 
diet study of the Kittlitz's murrelet has not been completed, but based 
on stable isotope analysis (Hobson et al. 1994, p. 795; Hatch 2011, p. 
47; Allyn 2012, p. 102), stomach contents (Sanger 1983, p. 692; 
summarized in Day et al. 1999, p. 9), fish-holding observations (Agness 
2006, p. 119; Kuletz et al. 2008, p. 26), fish netted below foraging 
Kittlitz's murrelets (Kuletz et al. 2003a, pp. 23, 28), and chick meal 
deliveries (Naslund et al. 1994, p. 46; Kaler et al. 2011, p. 15; 
Lawonn 2012, pp. 27-28; Kaler, unpublished data; Kissling, unpublished 
data), this species is known to feed on neritic macrozooplankton, such 
as copepods, amphipods, and euphasiids, and forage fishes, primarily 
Pacific sand lance, but also capelin, Pacific herring, Pacific sandfish 
(Trichodon trichodon), walleye pollock, kelp greenling, Atka mackerel, 
Pacific cod, and rockfish and smelt species (see Foraging, above, for a 
more complete description of diet and foraging preferences). Given the 
diverse diet of the Kittlitz's murrelet and its ability to forage 
successfully in a variety of marine habitats, and perhaps freshwater, 
we assume that this species has the ability to switch prey based on 
local availability when self-feeding, like many other seabird species, 
including the marbled murrelet (Litzow et al. 2002, p. 292; Ostrand et 
al. 2004, p. 73; Becker et al. 2007, p. 274; Ito et al. 2009, p. 282).
    The collective, complex process of ocean acidification is a global 
problem that will intensify with continued carbon dioxide emissions and 
may significantly affect marine ecosystems. Oceans absorb carbon 
dioxide from the atmosphere and store it as carbonic acid. Since the 
beginning of the industrial revolution, the pH of ocean surface waters 
has decreased from 8.2 to 8.1 (0.1 units) (Markon et al. 2012, p. 40). 
Although this change in pH seems small, it equates to a 20 percent 
increase in acidity and a subsequent decrease in carbonate compounds 
(primarily aragonite and calcite) necessary for calcifying organisms to 
construct tissues such as skeletons and shells (Markon et al. 2012, p. 
40). By 2100, ocean surface pH is expected to decrease another 0.3-0.5 
units (Caldeira and Wickett 2005, p. 1). High-latitude regions are 
particularly vulnerable to ocean acidification because cold ocean 
temperatures increase the solubility of carbon dioxide and precondition 
the seawater to have lower calcium carbonate concentrations and 
saturation states compared to more temperate ocean environments (Fabry 
et al. 2009, p. 161; Mathis et al. 2011, p. 2; Markon et al. 2012, p. 
40). Furthermore, in the Arctic Ocean, the carbonate mineral saturation 
state is expected to decrease with increasing sea ice melt (Bates and 
Mathis 2009, p. 2433). Although the biological effects of ocean 
acidification are far from clear, the ability to tolerate its apparent 
impacts is species-specific and varies within phyla and between closely 
related species (Whiteley 2011, pp. 257-258), making it difficult to 
generalize potential impacts to a single species, like the Kittlitz's 
murrelet. High-latitude planktonic and benthic calcifiers, especially 
pteropod snails, a common prey item for various zooplankton and fish 
(e.g., pollock, salmon, cod), are expected to be most affected by ocean 
acificiation (Fabry et al. 2009, p. 164). Consequently, as a top 
predator in the marine ecosystem, the Kittlitz's murrelet may 
experience alterations to underlying food webs. However, this species 
has a diverse diet (except when nesting), appears to have the ability 
to switch prey when necessary, and can forage successfully in a variety 
of marine habitats (see Foraging, above). We acknowledge that ocean 
acidification is occurring and is expected to continue, but, based on 
the best available information, we conclude that projected ecosystem 
changes as a result of ocean acidification are not having or will not 
have population- or species-level impacts on the Kittlitz's murrelet.
    Variability in ocean temperatures alone can disrupt complex marine 
food webs by affecting the productivity or abundance of lower trophic 
levels, thereby influencing higher trophic levels and the balance in 
predator-prey relationships (Hazen et al. 2012, p. 2). As ocean 
temperatures change, we anticipate poleward shifts in distribution of 
species that have limited temperature ranges (Overland and Stabeno 
2004, p. 309; Perry et al. 2005, p. 1914; Stabeno et al. 2007, p. 2605; 
Mueter and Litzow 2008, pp. 316-317; Mueter et al. 2009, p. 106), 
changes to the thermohaline circulation (part of the large-scale ocean 
circulation that is driven by global density gradients) (Haufler et al. 
2010, p. 10) thereby influencing nutrient input and mixing (Mueter et 
al. 2009, pp. 99, 107), variability in the timing and magnitude of 
spring phytoplankton blooms (Stabeno et al. 2007, p. 2612; Janout et 
al. 2010, p. 13), and changes in the local abundance of forage fish 
(Hunt et al. 2002, pp. 5835-5842; Abookire and Piatt 2005, pp. 236-238; 
Becker et al. 2007, pp. 267-269). However, available information does 
not allow us to project the magnitude or direction of possible impacts 
to the Kittlitz's murrelet or its prey as a result of increased ocean 
temperatures, especially given additional natural processes, such as 
inter-annual to decadal-scale ocean variability and large-scale regime 
shifts.
    Several climate regime shifts and subsequent community or taxomonic 
reorganizations have occurred in the North Pacific and Arctic oceans 
over the last few decades (Anderson and Piatt 1999, p. 120; Hare and 
Mantua 2000, p. 103; Litzow 2006, p. 1387; Brodeur et al. 2008, p. 108; 
Flint 2013, p. 59). These regime shifts often, but not always, 
corresponded to a change in the PDO index between a cold (negative) 
phase and a warm (positive) phase (Mantua et al. 1997, pp. 1076-1077; 
Litzow 2006, p. 1387). It is well-recognized that there were major 
atmospheric, oceanographic and ecological changes near 1976-1977 with a 
shift from the negative to the positive phase of the PDO (Anderson and 
Piatt, 1999, pp. 119-120), followed by weaker, less defined shifts in 
1989 and 1998 (Litzow 2006, pp. 1390-1393; Overland et al. 2008, p. 92; 
Flint 2013, p. 61); retrospective analyses indicate that there were 
also North Pacific regime shifts in 1925 and 1947 (Mantua et al. 1997, 
p. 1075). It is difficult to assess impacts of these climatic regime 
shifts (or project them into the future) on the Kittlitz's murrelet, 
specifically, because we lack sufficient and reliable data (see 
Population Status and Trends,

[[Page 61782]]

above). In California, annual survival of marbled murrelet was 
positively associated with positive values (warm phase) of the PDO 
(Peery et al. 2006, p. 82). In contrast, declines in populations of 
marine birds, especially piscivorous (fish-eating) species, and fishes 
occurred in the Gulf of Alaska between 1972 and 1993, in response to a 
shift to a warm water regime in 1976-1977 (Piatt and Anderson 1996, pp. 
725, 731; Anderson and Piatt 1999, pp. 119-120; Agler et al. 1999, p. 
100; Litzow et al. 2002, p. 286). The impact of the regime shift was 
probably exacerbated in Prince William Sound by the Exxon Valdez oil 
spill in 1989. For some marine species, however, declines halted 
shortly following the 1989 regime shift (Flint 2013, pp. 61-62). 
Similarly, our multiple-populations trend analysis indicated that 
Kittlitz's murrelets declined at an average annual rate of about 30 
percent across multiple populations in the Gulf of Alaska between 1989 
and 2000, after which abundance appeared to have stabilized, possibly 
due to the minor regime shift in 1998 (see Population Status and 
Trends, above).
    Undoubtedly, the Kittlitz's murrelet will respond to changes in 
ocean conditions, including temperature, circulation, salinity, 
chemistry, and other physical characteristics. Evidence suggests that 
this species has been resilient (able to persist), adaptable (able to 
adapt), or both to previous and ongoing changes in its marine habitat, 
or has undergone a population shift in response to environmental 
change, as suggested by Day (2011, p. 52). Between 1907 and 2009, mean 
isotopic signatures of nitrogen, an indicator of dietary trophic level, 
declined in feathers of Kittlitz's murrelets in the Gulf of Alaska 
during the pre-breeding season, but not in the post-breeding season 
(Hatch 2011, pp. 27, 49). These results suggest that perhaps decreased 
prey resources over the last century have forced Kittlitz's murrelets 
to fish further down the food chain, but we do not have reliable 
information to demonstrate a rangewide effect to this species during a 
similar time period. In addition, stomach contents of 48 adult 
Kittlitz's murrelets collected at sea between 1969 and 1996 in the 
North Pacific Ocean do not indicate any major shift in diet or trophic 
level compared to more recent information on chick and adult diet (Day 
et al. 1999, p. 9; Allyn 2012, p. 100; Kissling 2013, in litt.). So, 
while we fully recognize that changes in ocean conditions as a 
consequence of climate change play a significant role in the population 
regulation and abundance of prey species to the Kittlitz's murrelet, 
available information does not suggest that these changes are a threat 
to the persistence of this species for two primary reasons. First, the 
Kittlitz's murrelet has a diverse diet throughout the year, indicating 
that it can successfully forage on many different taxa, can switch prey 
types presumably based on local availability, and can adapt to a 
variety of foraging conditions across its broad range. Only nesting 
Kittlitz's murrelets experience prey restrictions, but there is no 
evidence to suggest that changes in ocean conditions as a result of 
climate change are limiting or will limit high-quality chick meal 
deliveries, thereby affecting fledging rates, in the future. Second, we 
do not have sufficient evidence that would allow us to determine if 
Kittlitz's murrelet populations or the diet of this species have 
fluctuated concurrently with regime shifts or ocean warming and 
acidification. Therefore, the weight of evidence suggests that this 
species can respond to changing ocean conditions by switching prey, 
adjusting its behavior, or potentially shifting its distribution.

Contaminated Meltwater

    Climate warming and associated glacial melt may be increasing 
contamination of fresh and marine waters. This phenomenon has been 
studied most extensively in alpine freshwater catchments in Europe. 
Bogdal et al. (2009, pp. 8173-8175) used lake sediment core results to 
track fluxes of organochlorine contaminants (industrial chemicals and 
pesticides) beginning in the 1950s and found an initial peak in the 
1960s-1970s corresponding to peak air emissions in Europe, decreased 
levels in the1980s-1990s that were attributed to emission reductions, 
and a second peak since the late 1990s that the authors attributed to 
glacial melt. Recent organochlorine inputs to the lake are similar to, 
or higher than, those observed in the 1960s-1970s, with recent fluxes 
of the pesticide dichlorodiphenyl-trichloroethane (DDT) and its 
metabolites exceeding past fluxes by a factor of five (Bogdal et al. 
2009, p. 8176). In a follow-up study, Schmid et al. (2011, pp. 205-207) 
compared polycholorinated biphenyls (PCBs) and the pesticide DDT and 
its metabolites (DDTs) in the sediments of a glacial-fed lake to 
sediments in a nearby lake that lacked glacial inputs. During the past 
two decades, total PCB and DDT levels in the non-glacial lake sediments 
decreased, while those in the glacial-affected lake sediments 
increased, supporting the hypothesis that glaciers represent a 
secondary source of these pollutants (Schmid et al. 2011, p. 207). 
Similarly, in Alberta, Canada, a substantial percentage of current 
glacial melt originated from ice that was deposited between 1950 and 
1970, when organochlorines were more concentrated in the atmosphere 
than they are now, or were before 1950 (Blais et al. 2001, pp. 410, 
414-415) and the concentrations of persistent organic pollutants (POPs) 
were, on average, 29 times higher in the glacial stream, relative to a 
nearby non-glacial valley stream (Blais et al. 2001, p. 414).
    Results of contaminant studies conducted in alpine freshwater lake 
systems may not be relevant or directly comparable to the physical and 
chemical processes associated with coastal and tide-water glaciers. In 
the polar coastal environment of Antarctica, cesium-137, a ubiquitous 
radionuclide contaminant associated with historical nuclear weapons 
testing, exhibited an abrupt concentration increase in recent sediments 
relative to older sediments (Sanders et al. 2010, pp. 422-423). While 
results are limited to a single sediment core (so extrapolation should 
be conducted with caution), the authors hypothesized that increased 
snow and ice melt from the uplands and enhanced sediment transport have 
resulted in net movement of cesium-137 from the coast into the marine 
environment. We are unaware of comparable contaminant studies from 
coastal ice fields or alpine glaciers in Alaska; therefore, we have no 
basis from which to determine the significance of glacial meltwater as 
a potential source of contamination to the Kittlitz's murrelet (see 
Environmental Contaminants, below).

Loss of Winter Sea Ice

    Until recently, there was little information about the movements 
and distribution of the Kittlitz's murrelet outside of the breeding 
season, which is when most surveys are completed. Within the last few 
years, research demonstrated that individuals depart breeding sites in 
the Gulf of Alaska and Aleutian Islands in July and August and migrate 
offshore to areas in the Bering, Chukchi and western Beaufort seas, 
where they apparently remain until late October (Day et al. 2011, pp. 
57-59; Madison et al. 2012, p. 1; Kuletz, unpublished data) (see 
Habitat and Life History, above). In November, as sea ice builds in the 
Chukchi and Beaufort seas, Kittlitz's murrelets begin to move south 
into open water of the Bering Sea where at least some individuals 
winter in open water leads and polynyas of the annual sea ice (Day et 
al. 1999, p. 7; Kuletz and Lang 2010, pp. 39-43; Day et al. 2011,

[[Page 61783]]

p. 59). These observations suggest that the Kittlitz's murrelet's 
winter distribution may be associated with winter sea ice in the Bering 
and Chukchi seas, which is declining rapidly and projected to continue 
declining (Douglas 2010, p. 1). However, to date, there has been little 
survey effort in the Gulf of Alaska where winter sightings indicate 
that some individuals are year-round residents or over winter in the 
ice-free waters of south-coastal Alaska (Klosiewski and Laing 1994, p. 
83; Kendall and Agler 1998, pp. 55-56; Day et al. 1999, pp. 4-5; 
Stenhouse et al. 2008, p. 61; Kissling, personal observation). We 
recognize the post-breeding northward migration and the occurrence of 
the Kittlitz's murrelet in open leads and polynas of the Bering and 
Chukchi seas in the winter and spring, but the data are limited and 
preliminary. In addition, the variable patterns of distribution and 
types of habitat used make it difficult to draw conclusions about the 
Kittlitz's murrelet's use of non-breeding habitat. Therefore, we have 
no basis from which to determine whether or not the loss of winter sea 
ice would negatively affect the habitat of the Kittlitz's murrelet.

Summary of Climate Change

    To summarize, climate change is modifying the marine and 
terrestrial habitats of the Kittlitz's murrelet. Although we can 
hypothesize about the various mechanisms by which Kittlitz's murrelets 
could be affected by these changes, we have not identified a causal 
link that is or will be causing a population- or species-level effect. 
Among the stressors evaluated, there are two that raise concern because 
they could negatively affect reproductive success of Kittlitz's 
murrelets, which was found to be consistently poor at sites where it 
was studied (see Reproductive Performance, above). These stressors are 
(1) The increasing distance between nesting and foraging habitats as a 
result of glacial recession and subsequent primary succession; and (2) 
changes in the foraging habitats due to glacial recession that could 
affect foraging efficiency or access to high-quality prey during chick 
rearing. However, the underlying mechanisms of these stressors are only 
working hypotheses; there is little information available to evaluate 
the significance of these stressors or potential implications to the 
Kittlitz's murrelet at the population or species level now or in the 
future.
    Although the Kittlitz's murrelet is generally associated with 
glacial-influenced habitats during the breeding season, this species is 
broadly distributed across many areas that have been deglaciated for 
thousands of years, and it nests and forages successfully in a variety 
of habitats. There is too much spatial and temporal variation in the 
species' habitat use to conclude that ice is an essential part of its 
life history and there is no evidence to suggest that Kittlitz's 
murrelets in glacial-affected areas outperform those in non-glaciated 
areas. Their seasonally varied and diverse diet at multiple trophic 
levels and apparent ability to switch prey types demonstrate 
adaptability to interannual and decadal-scale ocean variability and 
changes in ocean conditions that are likely to influence prey of the 
Kittlitz's murrelet. Furthermore, changes in forage quality, quantity, 
or distribution is uncertain at this time. Although contaminated 
meltwater from glaciers and the loss of winter sea ice may be altering 
marine habitats within this species' range, we have little information 
to evaluate these potential threats to the Kittlitz's murrelet. Thus, 
available information does not suggest that possible projected changes 
to the marine and terrestrial habitats used by the Kittlitz's murrelet 
as a result of climate change will be so great as to pose a threat to 
the persistence of this species at the population or species level now 
or in the future.

Environmental Contaminants

Persistent Organic Pollutants
    Kittlitz's murrelets may be exposed to contaminants from site-
specific sources, including former military sites, and from global 
atmospheric transport, so specific sources may be distant from the 
location of measurement. Within the range of the Kittlitz's murrelet, 
we tallied 2,537 contaminated sites and spills within 62 mi (100 km) of 
the shoreline that occurred between 1995 and 2012, most of which 
primarily affected land resources (n=2,077), not marine resources 
(n=460) (Alaska Department of Environmental Conservation 2013a). The 
majority of these spills was small in volume, localized and generally 
associated with villages, small towns, or urban areas (e.g., heating 
oil tanks and lines), primarily near Anchorage and Barrow (see Marine 
Oil Pollution, below, for more detailed discussion on marine-related 
spills). We also reviewed mining exploration, development, and 
production sites in Alaska to evaluate future potential contamination 
(or disturbance) sites near nesting habitat of the Kittlitz's murrelet 
(Szumigala et al. 2010, pp. 10, 39, 43). Generally, spatial overlap of 
contaminated sites with suitable nesting habitat or known areas of 
marine concentrations of the Kittlitz's murrelet was low, indicating 
that exposure to any point-source contamination would also be low.
    Nonetheless, sympatric waterbird species to the Kittlitz's murrelet 
are exposed to contaminants, especially POPs, including PCBs, other 
organocholorines, and mercury. Pelagic cormorants (Phalacrocorax 
pelagicus) and red-faced cormorants (P. urile) throughout the Aleutian 
Archipelago had greater levels of PCB, hexachlorobenzene (HCB), DDE (a 
DDT metabolite), and trans-nonachlor, all of which are persistent 
organochlorine contaminants, in the western Aleutian Islands compared 
to the eastern islands (Rocque and Winker 2004, pp. 761-762), with 
identified sources including former military installations (p. 764). 
Similarly, total PCBs were proportionally the most abundant persistent 
organochlorines in glaucous-winged gulls (Larus glaucescens), northern 
fulmars (Fulmarus glacialis), and tufted puffins at several locations 
within the Aleutian Islands (Ricca et al. 2008, pp. 314-315), again 
with military sites the proposed sources. Concentrations of 
organochlorine contaminants in tufted puffins were generally lower than 
other species, with the exception of one sample from East Adak near 
Sweeper Cove, a site of known PCB contamination (Ricca et al. 2008, p. 
316). Collectively, these results suggest significant point sources of 
contamination at sites such as Adak, Amchitka, and to a lesser extent 
Kiska islands, all in the Aleutian Archipelago and within the range of 
the Kittlitz's murrelet. High concentrations of PCBs, DDE, and 
chlordanes in seabirds from Buldir Island, the most westerly site 
sampled and which lacks a point source for military pollution, suggest 
that atmospheric transport from Eurasian sources may also be important. 
For example, tufted puffins, black-legged kittiwakes (Rissa 
tridactyla), and short-tailed shearwaters (Puffinus tenuirostris) were 
exposed to recently applied DDT obtained from a distant source (Ricca 
et al. 2008, p. 320).
    These persistent contaminants were also detected in Kittlitz's 
murrelets from Icy Bay, Alaska (Matz, Service, 2012, unpublished data), 
but at concentrations that are not of concern for adult mortality or 
reproduction. In 10 composited adult plasma samples, total PCBs were at 
concentrations below those associated with reduced hatching success and 
hatchling mass in glaucous gulls (L. hyperboreus), abnormal male 
reproductive behaviors in American kestrels (Falco sparverius) and 
glaucous

[[Page 61784]]

gulls (Harris and Elliott 2011, pp. 486-487), or poor adult return-to-
colony in Caspian terns (Hydroprogne caspia, formerly Sterna caspia) 
from the Great Lakes (Mora et al. 1993, p. 328). On a congener basis 
(related chemicals), PCB congeners common in marine environments or 
that are environmentally persistent due to a high percentage of 
chlorine were detected in the majority of samples, but at very low 
concentrations, and the four most toxic (``dioxin-like'') individual 
PCB congeners were not detected. Other congeners detected in the 
majority of samples were also at very low concentrations. Although the 
best sample in which to measure DDE is eggs, plasma concentrations of 
Kittlitz's murrelets were very low compared to lethal levels in liver 
and brain concentrations in a variety of birds (summarized by Blus 
2011, pp. 428-430). Similarly, concentrations of these persistent 
contaminants in one composite sample of livers taken from four 
Kittlitz's murrelet chicks found dead at nests on Agattu Island were 
low and not of concern (Lance, Service, 2013, unpublished data). Other 
POPs of emerging concern, such as polybrominated diphenyl ethers that 
are used as flame retardants, were not detected in Kittlitz's murrelet 
blood from Icy Bay, Alaska (Matz, unpublished data). In conclusion, 
PCBs, DDE, and other organochlorine contaminants were not detected at 
deleterious concentrations in plasma (n=10) or liver (n=1) of 
Kittlitz's murrelets from Alaska, so, with the caveat that few data are 
available, we find that these contaminants are currently not considered 
to have population- or species-level effects now or in the future.
Mercury
    Mercury is a global contaminant of concern for aquatic species, 
including numerous seabirds (e.g., black-footed albatross [Phoebastria 
nigripes]) (Vo et al. 2011, p. 1). However, the toxicological 
significance of actual mercury concentrations in marine birds and 
animals is not clear, as they appear to tolerate much greater mercury 
concentrations than freshwater organisms due to different selenium-
related detoxification abilities (Burger et al. 1997, p. 167; Ikemoto 
et al. 2004, pp. 402, 404). For species with high or variable selenium 
exposure, such as marine birds like the Kittlitz's murrelet, it is 
necessary to evaluate selenium concentrations and their effect on 
mercury toxicity to generate reliable tissue-specific mercury effect 
thresholds (Spalding et al. 2000, pp. 419-420). However, because there 
are too few studies that document mercury concentrations and effects in 
marine birds, we cautiously relied on established toxic effect levels 
from other, mostly freshwater, birds to assess mercury concentrations 
in feathers, whole blood, and eggshells of the Kittlitz's murrelet.
    Threshold feather concentrations for adverse reproductive effects 
(including reproductive behavioral changes, reduced reproductive output 
and sterility; Eisler 1987, pp. 62-63) in various species' range from 
5-65 parts per million (ppm) dry weight (dw), depending on the species 
(Burger and Gochfeld 1997, p. 164). For feather mercury concentrations, 
the most commonly used toxicity threshold level for potential adverse 
effects is 5 ppm dw, but it is highly dependent on species (Blevin et 
al. 2013, p. 6). For example, adult great skuas (Stercorarius skua) in 
the Shetland Islands had adult feather mean mercury concentrations of 
7.0 ppm, with no apparent effects on survival or reproduction (Thompson 
et al. 1991, p. 678), and for the common loon (Gavia immer) the adverse 
effect threshold for adults is 40.0 ppm in feathers (Evers et al. 2008, 
p. 69). Mean feather mercury concentrations of adult Kittlitz's 
murrelets varied significantly with no obvious pattern among geographic 
areas in Alaska. In the Aleutian Islands, feather mercury 
concentrations averaged 2.06 ppm dw on Agattu Island, but were 
significantly higher at Adak Island (9.15 ppm dw) (Kenney, Service, 
2007-2012, unpublished data). Similarly, in southeastern Alaska, mean 
feather mercury concentrations in 301 adult Kittlitz's murrelets from 
Icy Bay were 1.22-1.58 ppm dw (Folsom et al. 2009, p. 44; Kenney, 
unpublished data; Matz, unpublished data), but were much higher in 
Glacier Bay (9.00 ppm dw) (Kenney, unpublished data). Although 
accumulated mercury in feathers of some individual Kittlitz's 
murrelets, especially those at Adak Island and Glacier Bay, was 
relatively high, it is difficult to reconcile and interpret the large 
variation among individuals and study sites.
    Whole blood mercury values in Kittlitz's murrelets from Icy Bay are 
equally inconclusive at the population level, but may raise concern for 
some individuals. Mean blood concentrations of Kittlitz's murrelets 
from Icy Bay were variable among years; in 2008-2009, concentrations 
averaged 0.32 ppm wet weight (ww) (Folsom et al. 2009, p. 44; Kenney, 
unpublished data), and in 2011, concentrations were 4.5 ppm ww (Matz, 
unpublished data), perhaps reflecting differences in prey consumed 
across years. For comparison, whole blood mercury concentrations of 
marbled murrelets in Port Snettisham, southeastern Alaska, in 2008 were 
0.22 ppm ww (Folsom et al. 2009, p. 44). Threshold concentrations in 
blood for reproductive effects in adult common loons and bald eagles 
(Haliaeetus leucocephalus) were 3.00 and 6.54 ppm ww, respectively 
(Weech et al. 2006, p. 1438; Evers et al. 2008, p. 79). However, given 
the variation in whole blood concentrations of Kittlitz's murrelets 
among years (range across all years=0.04-15.1 ppm ww) and lack of 
information on selenium levels of this species, we can only tentatively 
conclude that blood mercury concentrations in some individual 
Kittlitz's murrelets from Icy Bay in some years may be at the low end 
of reproductive effect levels or below effect levels based on their 
marine status.
    Adverse effect thresholds of mercury concentrations in eggshells 
have yet to be established, but mercury concentrations of 0.90-18.0 ppm 
ww in whole eggs have been associated with poor hatching success and 
increased chick mortality in some avian species (Eisler 1987, p. 2; 
Burger and Gochfeld 1997, p. 163-164). Mean mercury concentrations in 
eggshells collected from 20 Kittlitz's murrelet nests on Agattu Island 
appear to be low (0.016 ppm dw) (Kenney, unpublished data). For 
comparison, mercury concentrations in eggshells of Audouin's gulls (L. 
audouinii) ranged from 0.13-0.18 ppm dw and were not correlated with 
reproductive impairment (Sanpera et al. 2000, pp. 120-121).
    Since the preindustrial period, human activities have increased the 
amount of mercury cycling in the environment by about a factor of three 
(Selin 2009, p. 55). If emissions of mercury into the atmosphere 
continue, ocean concentrations will continue to increase (Selin 2009, 
p. 55), possibly causing adverse effects for marine species, such as 
the Kittlitz's murrelet. Yet, substantial variability exists among bird 
species in their sensitivity to mercury, and no information exists for 
Kittlitz's murrelet mercury thresholds or selenium levels. Current data 
on mercury concentrations in feathers, blood, and eggshells of 
Kittlitz's murrelets are both spatially and temporally limited, but 
suggest that perhaps some individuals in some years may exceed commonly 
used adverse effects thresholds established for other bird species. 
However, owing to the high variability in concentration values and the 
apparent higher tolerance of marine species to mercury toxicity, we

[[Page 61785]]

find that mercury does not pose a population- or species-level threat 
to the Kittlitz's murrelet now or in the future.
Marine Oil Pollution
    Petroleum hydrocarbons in marine waters are considered among the 
most potentially harmful contaminants to marine birds and their prey 
(Martin and Richardson 1991, p. 533). Acute and chronic exposure to oil 
pollution can have both direct and indirect impacts to marine birds 
(Yamato et al. 1996, p. 381; Esler et al. 2000, pp. 839, 844). Oiling 
of feathers causes loss of insulating capacity and can lead to death 
from hypothermia, smothering, drowning and ingestion of toxic 
hydrocarbons (Peterson et al. 2003, p. 2082). Marine birds ingest oil 
by preening their oiled feathers or by consuming oiled prey. Long-term 
or chronic effects of oiling are more difficult to document, but 
certainly exist, and are most likely to impact those species that are 
intimately associated with sediment for egg-laying or foraging 
(Peterson et al. 2003, p. 2083), such as sand lance, herring, and many 
prey species of the Kittlitz's murrelet. However, it is often 
challenging to demonstrate a population- or species-level impact to a 
species because pre-event baseline data are rarely available (Carter 
and Kuletz 1995, p. 261).
    The Kittlitz's murrelet is considered highly vulnerable to marine 
oil pollution because this species spends most of its annual cycle at 
sea, forages by diving and pursuing prey, and is typically found 
nearshore (King and Sanger 1979, p. 234; Day et al. 1999, p. 9; Day and 
Nigro 2000, p. 5). At least 19 major oil spills have occurred within 
the range of the Kittlitz's murrelet since 1976 (Alaska Department of 
Environmental Conservation, 2013b) and some have resulted in direct 
mortality of individuals (Kuletz 1996, p. 781; Piatt et al. 2007, pp. 
72-77). However, estimating total mortality of Kittlitz's murrelet is 
complicated by their similar morphology to the typically more common 
marbled murrelet, which results in a large proportion of unidentified 
murrelets, and their small size relative to other marine birds and 
mammals. In addition, due to the remoteness and exposed marine waters 
of Alaska and Russia, response to oil spills within the range of the 
Kittlitz's murrelet is often hampered by weather and lack of 
infrastructure.
    In March 1989, the commercial oil tanker Exxon Valdez spilled 
nearly 11.6 million gallons of crude oil into the marine environment of 
Prince William Sound, resulting in roughly 30,000 oiled seabird 
carcasses found on the beaches and an estimate of hundreds of thousands 
of seabird mortalities in total (Piatt and Anderson 1996, p. 720). A 
minimum estimate of direct mortality was 8,400 Brachyramphus murrelets, 
including a minimum of 255 Kittlitz's murrelets (not including 
unidentified murrelets) and at least 51 definitively identified 
Kittlitz's murrelet carcasses (Kuletz 1996, p. 781; Piatt et al. 2007, 
p. 74). Mortality estimates of over 1,000 Kittlitz's murrelets from 
this spill have been reported (van Vleit and McAllister 1994, p. 5). 
Since the Exxon Valdez oil spill, 11 other major spills have occurred 
in the coastal waters of Alaska, but data on Kittlitz's murrelet 
mortalities are limited. In August 2001, the fishing tender F/V Windy 
Bay struck a reef and sank in northern Prince William Sound, creating 
an oil slick from hydrocarbons on board (35,000 gallons of diesel and 
hydraulic fuel and lube oil) (Kuletz et al. 2003a, pp. 57-61; Piatt et 
al. 2007, pp. 73-74). Only 7 bird carcasses were retrieved, but 6 were 
marbled murrelets and 4 of those were newly fledged juveniles, 
extrapolating to a mortality estimate of roughly 100 murrelets (Piatt 
et al. 2007, p. 74); no Kittlitz's murrelets were retrieved, but they 
were present in the area and could have died without being recovered 
(Kuletz et al. 2003a, pp. 57-61). In December 2004, the M/V Selandang 
Ayu spilled 500,000 gallons of fuel oil (bunker C and diesel) into 
Makushin Bay, Unalaska Island, in the eastern Aleutians. Only five 
Brachyramphus murrelet carcasses (two marbled and three unidentified 
murrelets) were recovered after this oil spill (Byrd, Service, 2004, 
unpublished data), although this area is frequented by Kittlitz's 
murrelets in the breeding season (Madison et al. 2011, p. 116). We are 
aware of only four major oil spills within the range of the Kittlitz's 
murrelet in Russia (Sakhalin Island, Sea of Okhotsk), and we lack any 
information about possible murrelet mortality as a result of those 
spills, all of which occurred between September and January, a period 
in which Kittlitz's murrelets initiated post-breeding migration or 
settled into their winter habitats. Oil spills in Russia are not well-
documented, but probably occur frequently (Blokov 2012, p. 3). 
Kittlitz's murrelet mortality from fuel spills and petroleum 
contamination may go largely unobserved in the vast and remote waters 
of Alaska and eastern Russia, but lack of observed mortality from 
marine oil pollution does not confirm its absence. However, it is 
difficult to assess the impacts from these spills and others on the 
Kittlitz's murrelet population. An additional aspect of oil spills is 
the large, but temporary increase in vessel traffic in the spill area 
during response activities, as documented during large (e.g., Exxon 
Valdez) and small (e.g., Windy Bay) spills and vessel groundings alike 
(Kuletz et al. 2003a, pp. 30-31).
    We examined the spatial and temporal overlap of 460 oil spills and 
contaminated sites that primarily impacted marine resources in coastal 
Alaska between 1995 and 2012, and distribution and abundance of 
Kittlitz's murrelet (Alaska Department of Environmental Conservation, 
2013a). We identified four biologically-meaningful periods within the 
annual cycle of the Kittlitz's murrelet: Breeding (May-July), post-
breeding (August-October), winter (November-February), and pre-breeding 
(March-April). We estimated relative densities of Kittlitz's murrelets 
at sea by marine ecoregion (n=30 in Alaska; Piatt and Springer 2007, 
pp. 524-525) and period (Kuletz, unpublished data; see Population 
Status and Trends, above, for information on abundance estimates). Most 
spills occurred during the post-breeding period (43 spills per month), 
followed by the winter and breeding (38 spills per month each), and 
pre-breeding (33 spills per month) periods. Across all periods, most 
(83 percent) of the spills were small, releasing less than 1,000 
gallons of substance, and 78 percent consisted of non-crude oil 
(diesel), which is lighter and disperses more quickly than crude oil. 
However, there is no evidence to suggest that the immediate impact to 
marine birds from non-crude oil is less problematic than crude oil 
(Piatt et al. 2007, p. 73). There were 12 large spills (greater than 
10,000 gallons); 8 of these consisted of non-crude oil, and 7 occurred 
due to grounding or sinking vessels. We concluded that there was low 
spatial overlap between these spills and Kittlitz's murrelet 
distribution in the post-breeding, winter, and pre-breeding periods, 
but low-moderate overlap during the breeding period, primarily in 
Prince William Sound and, to a lesser extent, Adak Island in the 
central Aleutian Archipelago.
    Marine traffic within the range of the Kittlitz's murrelet is 
forecasted to increase in the next 25 years (Det Norske Veritas and ERM 
West 2010, pp. 60-61). The vessel fleet in or passing through marine 
waters of Alaska and eastern Russia is comprised of container vessels, 
bulk carriers, cargo vessels, gas and car carriers, cruise and tank 
ships, tugs and barges, fishing vessels, and government vessels. Cruise 
ships and recreational boating activity have increased and continue to 
increase in

[[Page 61786]]

the glaciated fjords of Glacier Bay (federally managed waters requiring 
an entry permit), Yakutat Bay, Prince William Sound and Kenai Fjords in 
south-coastal Alaska (Day et al. 1999, pp. 20-21; Jansen et al. 2006, 
p. 1186; Hoover-Miller et al. 2013, p. 3), where large numbers of the 
Kittlitz's murrelet are found in the breeding season (Arimitsu et al. 
2011, p. 18; Kissling et al. 2011, pp. 7-8; Kuletz et al. 2011a, pp. 
99-101; Piatt et al. 2011, pp. 68-70).
    Trans-Pacific shipping routes that connect North America and Asia 
overlap with Kittlitz's murrelet distribution in the northern Gulf of 
Alaska and throughout the Aleutian Islands, most of which are part of 
the Alaska Maritime National Wildlife Refuge. Within a 1-year period, a 
minimum of 2,219 large commercial ships transited along this route, 
known as the North Pacific Great Circle route, with most vessels 
traveling offshore across the Gulf of Alaska, but nearshore along the 
Aleutian Islands, where most vessels cross the island chain twice 
during each transit (Det Norske Veritas and ERM West 2010, pp. 5-6; 
Kuletz, unpublished data). The nearshore portion of this popular 
shipping route likely presents the greatest oil exposure risk to the 
Kittlitz's murrelet. In the next 25 years, both westbound and eastbound 
traffic along the North Pacific Great Circle route are expected to 
increase, but the rate of increase is dependent on economic activity 
(gross domestic products) (Det Norske Veritas and ERM West 2010, pp. 
60-61, 65). However, based on the certainty that oil spills will 
continue to occur in this region where high volumes of ships traverse 
dangerous waters, the Alaska Maritime National Wildlife Refuge is 
considered among the most vulnerable refuges in the country (National 
Wildlife Refuge Association 2005, p. 10).
    Projections of shipping traffic from the Bering Sea into the 
Chukchi and Beaufort seas along the Northwest Passage route are highly 
dependent on the future of natural resource development, regional trade 
growth, and future commodity prices for the natural resources being 
developed in and around these regions (Det Norske Veritas and ERM West 
2010, p. 67). A key choke point is the Bering Strait, the migratory 
channel between the Bering and Chukchi seas, where vessel traffic has 
increased in the past decade and is projected to increase as extent and 
duration of seasonal sea ice decreases. The marine waters near Point 
Barrow, which separates the Chukchi and Beaufort seas, will likely 
experience increased traffic, and this is an area where Kittlitz's 
murrelets have been observed in late summer and fall (Madison et al. 
2012, p. 1; Kuletz, unpublished data).
    Offshore oil and gas development within the range of the Kittlitz's 
murrelet is also projected to increase in the future. In 2012, Royal 
Dutch Shell Oil (Shell) initiated offshore exploration in the Beaufort 
and Chukchi seas with a plan to drill up to 2 and 3 wells per year in 
each location, respectively, but after the drilling unit Kulluk was 
driven aground near Kodiak Island in a severe storm in December 2012, 
Shell paused exploration in 2013, to prepare equipment and emergency 
plans (Shell 2013). No Kittlitz's murrelet mortalities or injuries were 
reported as a consequence of the Kulluk grounding, but Kittlitz's 
murrelets have been observed in the vicinity of the accident in the 
winter months (Stenhouse et al. 2008, p. 60). In Cook Inlet, oil and 
gas activity is also increasing, but most lease sales have occurred in 
the upper portion of the inlet where Kittlitz's murrelets are less 
abundant compared to the lower portion (Kuletz et al. 2011b, p. 88; 
Alaska Department of Natural Resources 2013a). Recently, a lease sale 
for geothermal energy on western Augustine Island in Lower Cook Inlet 
was completed (Alaska Department of Natural Resources 2013b); this is 
an area frequented by individual Kittlitz's murrelets during post-
breeding migration (Madison et al. 2012, p. 1).
    It is reasonable to assume that as marine traffic and oil and gas 
development increase, so does the risk of petroleum contamination from 
both accidental spills and routine vessel operation. Because the 
Kittlitz's murrelet distribution varies considerably among seasons, it 
is difficult to assess the future risk from marine oil pollution to 
this species, but its broad distribution and relatively low densities 
on the water throughout most of the year reduce the risk of population-
level impacts from any single event. Spill prevention is likely the 
best approach to reducing acute and chronic impacts of hydrocarbon 
contamination to the Kittlitz's murrelet. Baseline information on 
seasonal distribution and abundance of the Kittlitz's murrelet has 
improved significantly since 2000, which should help to inform future 
risk and spill response planning. Worldwide, oil tankers now under 
construction require double hulls and older tankers will be phased out 
of use. In the United States, single-hulled tankers should be 
completely phased out and replaced with double-hulled tankers by 2015 
(see Oil Pollution Act [OPA] of 1990, below) (Det Norske Veritas and 
ERM West 2010, p. 54). While we recognize that hydrocarbon exposure is 
a possible acute and chronic source of mortality of individual 
Kittlitz's murrelets throughout their range and it will likely increase 
in the future, we conclude that marine oil pollution alone does not 
threaten the persistence of the Kittlitz's murrelet at the population 
or species level now nor is it likely to do so in the future.

Conservation Efforts To Reduce Habitat Destruction, Modification, or 
Curtailment of Its Range

    We are not aware of any non-regulatory conservation efforts, such 
as habitat conservation plans, or other voluntary actions that may help 
to ameliorate any potential threats to the marine or terrestrial 
habitats used by the Kittlitz's murrelet.
Summary of Factor A
    In summary, marine and terrestrial habitats of the Kittlitz's 
murrelet within select parts of its range are currently being modified 
by climate change, including loss of glaciers and changes in ocean 
conditions, and environmental contaminants, but we cannot predict the 
response of Kittlitz's murrelet to future changes in habitat 
conditions. This species uses a variety of habitats across a broad 
range, does not have a highly specialized diet, and appears to be a 
flexible forager. We are not aware of habitat characteristics required 
by or significantly advantageous to the Kittlitz's murrelet that are 
currently limited or may become limited in the future. Although sites 
that include tidewater glaciers apparently support greater densities of 
Kittlitz's murrelets during the breeding season compared to non-
glaciated sites, there is little evidence to support the hypothesis 
that glaciers (or ice) are a required feature of nesting or foraging 
habitat or lead to better reproductive performance or survival of the 
Kittlitz's murrelet. Therefore, with limited data and assumptions, we 
conclude at this time that there is not likely to be a population- or 
species-level response of the Kittlitz's murrelet to the forecasted 
loss of glaciers, especially given that this species currently occurs 
in areas without glacial influence and that population trend has been 
stable since 2000, despite continued loss of glaciers.
    Because this species spends most of its life at sea, possible 
threats to the marine habitat of the Kittlitz's murrelet, especially 
those that reduce prey availability or foraging efficiency, are more 
pervasive and therefore more likely to impact the species at the 
population level. However, we did not

[[Page 61787]]

identify any measurable threats affecting the marine habitats used by 
this species that could have a population- or species-level impact. The 
Kittlitz's murrelet, like many marine species, is probably sensitive to 
oceanic regime shifts that occur on interannual to decadal time scales. 
However, we do not have sufficient years of demographic data to 
evaluate population-level response of the Kittlitz's murrelet to past 
regime shifts, nor are we able to project the frequency or magnitude of 
future regime shifts. We do know, however, that this species has 
persisted through several large-scale regime shifts in the last 
century, coupled with loss of glaciers, subsequent vegetation 
succession, ocean warming, increased environmental contaminants, and 
marine oil pollution. For all of these reasons, we consider the 
Kittlitz's murrelet to be resilient or adaptable, or both, to changes 
in its marine and terrestrial habitats. Thus, in the absence of an 
identified mechanistic link between Kittlitz's murrelet and glaciers, 
available information does not lead us to conclude that modifications 
to habitats used by the Kittlitz's murrelet as a consequence of climate 
change or environmental contaminants will negatively impact the 
viability of this species in the future.
    We conclude, based on the best scientific and commercial 
information available, that the present or threatened destruction, 
modification or curtailment of its habitat or range does not currently 
pose a threat to the Kittlitz's murrelet, nor is it likely to become a 
threat to this species in the future.
Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes
    The Kittlitz's murrelet was not historically, and is not currently 
a bird targeted by commercial or recreational interests (Day et al. 
1999, p. 17); overutilization from these sources is not a threat. In 
addition, overutilization for educational purposes has not been 
documented and is not considered a threat.
    During the last decade, a handful of research projects on 
Kittlitz's murrelet were initiated in several locations, some of which 
involved capturing and handling juvenile and adult live birds, 
collecting biological data and samples, attaching transmitters, and 
searching for and monitoring active nests. These methods, other than 
nest searching, are commonly used to study marbled murrelets in British 
Columbia (e.g., Lougheed et al. 2002, p. 309; Cam et al. 2003, p. 
1120), Washington (e.g., Bloxton and Raphael 2009, pp. 1-3), and 
California (e.g., Hebert and Golightly 2006, pp. 7-8; Peery et al. 
2006, p. 78), and, in some cases, have affected survival. For example, 
Peery et al. (2006, p. 85) found that radio-marked marbled murrelets 
had a lower probability of surviving the year after they were marked 
than non-radio-marked, but banded, murrelets, suggesting a radio-
transmitter effect. Radio-transmitters are known to affect other alcids 
by lowering reproductive success (Whidden et al. 2007, p. 206) and 
performance (Ackerman et al. 2004, p. 1229; summarized for all birds by 
Barron et al. 2010, p. 180), but not influencing diving behavior 
(Jodice and Collopy 1999, p. 1414). There is no evidence to suggest 
that capture and handling, radio-marking, or nest searching and 
monitoring has affected the reproductive performance or survival of the 
Kittlitz's murrelet.
    Few radio-telemetry studies of the Kittlitz's murrelet have been 
attempted. Pilot efforts in 2004 in Glacier Bay (Romano et al. 2007, 
pp. 120-121) and in 2006 in Kenai Fjords (Arimitsu et al. 2010, pp. 5-
6, 14-15) were successful, but transmitter retention was poor and 
sample sizes were limited; no capture-related injuries or mortalities 
were reported. In Icy Bay, 940 Kittlitz's murrelets were captured on 
the water (74 were later recaptured), and 271 individuals were fitted 
with radio-transmitters between 2005 and 2012 (Kissling, unpublished 
data). In 8 years of research, 2 capture-related mortalities and 12 
minor injuries (e.g., bent primary) were reported (Kissling et al. 
2010, p. 1; Kissling, unpublished data). Based on the large number of 
birds captured in Icy Bay, there was no relationship between lactate (a 
metabolite used as an index of muscle fatigue or stress) and handling 
or transport time, sex, capture attempt, time of year, body condition, 
age, or reproductive status (Kissling et al. 2010, p. 1). A comparison 
of three radio-transmitter attachment techniques (subcutaneous anchor, 
suture only, and waterproof tape) did not indicate differences in 
behavior at sea or breeding propensity of Kittlitz's murrelets 
(Kissling, unpublished data). In 2011 and 2012, radio-marked marbled 
murrelets reproductively outperformed radio-marked Kittlitz's murrelets 
(see Reproductive Performance, above), suggesting that the radio-
transmitter and marking were not responsible for the poor reproductive 
performance of Kittlitz's murrelets observed in those 2 years; these 
data are further supported by the low ratio of juvenile to adult 
Kittlitz's murrelets captured at sea in late summer (5 juveniles to 380 
adults) (Kissling, unpublished data). Unfortunately, too few radio-
marked Kittlitz's murrelets were recaptured across years to compare 
differences in annual survival rates, as done by Peery et al. (2006, p. 
85), but there was no acute survival effect to Kittlitz's murrelets 
detected 1, 3, and 5 days post-radio-marking, and a chronic effect is 
unlikely because transmitter retention is low (80-90 days) (Kissling, 
unpublished data). Similarly, radio-marked Kittlitz's murrelets were 
delivered to predator nests in proportion to their availability on the 
water and in comparable proportion to non-radio-marked murrelets, 
suggesting that the radio-transmitter did not increase predation rates, 
thereby decreasing survival of individual Kittlitz's murrelets (Lewis, 
Service, 2007-2012, unpublished data). In 2009 and 2011, similar radio-
marking efforts to study Kittlitz's murrelets in Prince William Sound 
(39 captured and 12 radio-marked birds) (Allyn 2012, pp. 95-96) and 
Glacier Bay (47 captured and 20 radio-marked birds) (Marcella et al. 
2012, p. 3) reported no capture-related injuries or mortalities.
    Between 2009 and 2012, 35 Kittlitz's murrelets were marked with a 
solar-powered satellite transmitter using two techniques (double prong 
and suture only) in 5 different locations across coastal Alaska 
(Madison et al. 2012, p. 1). No capture-related injuries or mortalities 
were reported in association with this effort, and there is no evidence 
to suggest that the satellite transmitters affected vital rates of 
individual Kittlitz's murrelets, although this has not been tested 
explicitly.
    Three research projects aimed to locate nests of Kittlitz's 
murrelets by searching on foot on Agattu (2006, 2008-2011) (Kaler et 
al. 2009, p. 365; Kaler, unpublished data), Adak (2010-2012) (Kenney 
and Kaler 2013, p. 74; Kenney, unpublished data), and Kodiak islands 
(2008-2012) (Corcoran and Mackey 2012, p. 1; Lawonn 2012, p. 16). After 
active nests were discovered, they were monitored by visiting every 3-
10 days (Kaler et al. 2009, p. 365), in stages (Corcoran and Mackey, 
2012, p. 1; Lawonn 2012, p. 19) or using remote still cameras with 
motion detection (Kaler et al. 2011, p. 4; Lawonn 2012, pp. 17-18). 
Five active nests were located and accessible in Icy Bay, and all were 
monitored using remote video cameras (Kissling, unpublished data). On 
Agattu and Kodiak islands, an experimental approach to test for 
possible adverse effects of researcher visits to active nests was 
employed; discovered nests were categorized as

[[Page 61788]]

either a control or disturbed nest (Kaler et al. 2011, p. 4; Lawonn 
2012, p. 17). Both studies concluded that nest visitation by 
researchers had a negligible, if any, effect on nest success (Kaler et 
al. 2011, p. 17; Lawonn 2012, pp. 30, 38).

Conservation Efforts To Reduce Overutilization for Commercial, 
Recreational, Scientific, or Educational Purposes

    We are not aware of any conservation efforts or other voluntary 
actions that may help to reduce overutilization for commercial, 
recreational, scientific, or educational purposes of the Kittlitz's 
murrelet.
Summary of Factor B
    In summary, we conclude that overutilization has not led to the 
loss of populations or a significant reduction in numbers of 
individuals of Kittlitz's murrelet. Given the relatively small number 
of Kittlitz's murrelets that are potentially directly affected by 
research activities, the lack of evidence to suggest that a measurable 
impact exists, and the relatively small portion of their range that is 
affected by researchers, we conclude that overutilization for 
commercial, recreational, scientific, or educational purposes is not a 
threat to the population of Kittlitz's murrelet, nor is it likely to 
become a threat in the future.

Factor C. Disease or Predation

Disease
    The recent emergence of bacterial, fungal, parasitic, and viral 
diseases, and biotoxins has affected populations of wild birds 
(summarized by Friend et al. 2001, pp. 294-295), including many 
seabirds (McShane et al. 2004, p. 3-66). Yet, available information on 
disease or parasites in the Kittlitz's murrelet is limited both 
spatially and temporally. Until recently, the only known parasite was a 
cestode (Alcataenia spp.) in two Kittlitz's murrelets from Kodiak 
Island (Hoberg 1984, p. 2297). Within the last few years, four adult 
and nine nestling Kittlitz's murrelets were necropsied. All nine 
nestlings were found dead at nest sites that were being actively 
monitored on Kodiak Island in 2011 and 2012, and all were in fair to 
good body condition and nutritional status (Lawonn 2012, p. 31; Shearn-
Bochsler et al. 2013, p. 1). Two adults were found dead from suspected 
raptor predation attempts in Glacier Bay (Kissling, unpublished data), 
one adult died during a capture-related incident in Icy Bay (Kissling, 
unpublished data), and one adult was found alive near Chignik with an 
apparent wing injury, but eventually died at a rehabilitation facility 
in Anchorage (Lance, unpublished data).
    Because of the varying condition and preservation method of the 
carcasses, not all of the 13 birds were tested equally for disease or 
parasites, but of those tested, no viruses, infectious diseases, or 
pathogenic bacteria were detected. These include negative tests for 
West Nile virus, avian influenza viruses, and avian paramyxoviruses, 
including Newcastle disease (Shearn-Bochsler et al. 2013, p. 1; 
Kissling, unpublished data; National Wildlife Health Center 2012a, b, 
c). All 13 birds were examined for parasites, and 8 of them had 
evidence of parasite infections; 6 of the juveniles contained an 
unknown species of nematode, and 2 of the adults contained both 
nematodes (Stegophorus spp. and Contracaecum spp.) and cestodes 
(presumably Alcataenia spp.) (Shearn-Bochsler et al. 2013, p. 1; 
Kissling, unpublished data). These parasites are widespread and 
relatively common in fish-eating birds (Muzaffar and Jones 2004, pp. 
130, 132-133). None of the individual parasite loads were substantial 
enough to have caused death, although parasites may potentially affect 
seabird population dynamics by selectively reducing fitness and 
reproductive success of individuals (Bried and Jouventin 2002, p. 284; 
Schreiber 2002, p. 193; Muzaffar and Jones 2004, p. 139).
    A subset of the carcasses was tested for presence of biotoxins, 
toxic substances produced by living organisms that are a consequence of 
algal blooms. Specifically, eight of the nestlings collected at Kodiak 
Island in 2011 and 2012 were tested for saxitoxin, a neurotoxin that is 
naturally produced by some species of dinoflagellates (Alexandrium 
spp.) and is the cause of paralytic shellfish poisoning (PSP), and 
domoic acid, a neurotoxin secreted by microscopic diatoms 
(Pseudonitzschia spp.) and is responsible for amnesic shellfish 
poisoning (ASP) (Horner et al. 1997, p. 1076; Shumway et al. 2003, p. 
2). Clinically, PSP can result in respiratory distress, muscular 
paralysis, and death, while ASP can lead to amnesia, coma, and death 
(Sumway et al. 2003, p. 2). Both of these biotoxins are known to kill 
or reduce survival of marine organisms (Nisbet 1983, p. 338; Beltran et 
al. 1997, p. 447; Lefebvre et al. 2000, p. 485; Shumway et al. 2003, 
pp. 5-6; Muzaffar and Jones 2004, p. 126), including the marbled 
murrelet (MacBean 1989, p. 134; Peery et al. 2006, pp. 83-84). The 
majority of the Kittlitz's murrelet nestlings (88 percent) tested 
positive for saxitoxin, but not for domoic acid (Shearn-Bochsler et al. 
2013, p. 1). High concentrations of saxitoxin were detected in the 
upper gastrointestinal contents and livers of the nestlings and were 
likely the cause of their deaths (Shearn-Bochsler et al. 2013, p. 1). 
Based on still images taken by remote cameras at their nest sites, the 
nestlings were fed sand lance shortly before their deaths, and chick 
death occurred within 3 hours of the meal delivery (Shearn-Bochsler et 
al. 2013, p. 1). All Brachyramphus murrelets reported to have died from 
PSP were juveniles (MacBean 1989, p. 134; Shearn-Bochsler et al. 2013, 
p. 1), suggesting perhaps lower toxicity thresholds for young 
murrelets, although only one adult was tested (negative) to determine 
saxitoxin concentrations for comparison to juveniles.
    Harmful algal blooms can be natural phenomena, but globally they 
appear to be increasing in frequency and severity in coastal areas, or 
at least reports of events have increased (Anderson et al. 2002, p. 
704; Sellner et al. 2003, p. 383). Blooms occur when environmental 
conditions change to be more favorable to phytoplankton growth and are 
generally attributed to two factors: (1) Natural processes, such as 
circulation, upwelling relaxation, and river flow; or (2) anthropogenic 
nutrient loading (Horner et al. 1997, p. 1084; Sellner et al. 2003, p. 
383). Human activities that can enhance nutrient input and stimulate 
harmful algal blooms in coastal waters can include aquaculture farming, 
agricultural and other fertilizer runoff, fossil fuel combustion, 
sewage and animal waste, and ballast water discharge (Anderson et al. 
2002, pp. 706-707; Sellner et al. 2003, pp. 384-385; Smayda 2007, p. 
602). Increased water temperatures as a result of climate change have 
also been identified as a possible contributor to increased frequency 
and intensity of toxic blooms (Horner et al. 1997, p. 1084; Moore et 
al. 2008, p. 3; Lewitus et al. 2012, p. 142).
    Saxitoxin and domoic acid toxicity have been present on the western 
coast of North America for hundreds of years, perhaps longer (Horner et 
al. 1997, p. 1083; RaLonde and Wright 2011, pp. 5-7; Lewitus et al. 
2012, p. 134). In Alaska, 183 incidences from 68 outbreaks of PSP on 
Kodiak Island, the Aleutian Peninsula, Prince William Sound, and 
southeastern Alaska were reported between 1973 and 2010 (RaLonde and 
Wright 2011, p. 5; Shearn-Bochsler et al. 2013, p. 1). There is less 
known about ASP in Alaska, but from the early 1990s to 2010, a number 
of incidences of domoic acid toxicity have been documented in 
shellfish, forage fish,

[[Page 61789]]

and marine mammals along the southern coast (RaLonde and Wright 2011, 
pp. 6-7). There is no evidence to suggest an increase in PSP or domoic 
acid concentrations in Alaska over the last few decades (Lewitus et al. 
2012, pp. 141, 145-146), nor is there evidence to support anthropogenic 
factors as promoters of Alexandrium or Pseudonitzschia blooms or toxic 
events in Alaska (Lewitus et al. 2012, pp. 142, 148).
    It is difficult to evaluate harmful algal blooms as a potential 
population- or species-level threat to the Kittlitz's murrelet because 
occurrences are unpredictable, are episodic, and appear to be 
localized. Furthermore, PSP-related deaths have only been documented in 
juveniles and the actual incidence and impacts, especially to adults at 
sea, may not be adequately reported. However, the results from Kodiak 
Island confirm that individual Kittlitz's murrelets are at risk for 
saxitoxin poisoning during harmful algal blooms. Because this is the 
only area for which Kittlitz's murrelets are known to die from PSP, it 
is worth noting that the greatest number of shellfish species affected 
and the highest concentrations of PSP across Alaska were reported from 
Kodiak Island (Lewitus et al. 2012, p. 135). For all of these reasons, 
based on the best available information, we conclude that harmful algal 
blooms are not a current threat to this species at the population or 
species level, nor will these blooms pose a threat in the future. There 
are insufficient data to assess fully the potential effects of diseases 
or parasites to the Kittlitz's murrelet, but based on available 
information, we conclude that these factors are currently not a threat 
to the species now or in the future.
Predation
    Predation can act as a strong selective force in the evolution of 
prey behavior (Lima and Dill 1990, p. 619) and was likely a major 
factor contributing to the development of Kittlitz's murrelet behavior. 
Secretive nesting habits, cryptic plumage, erratic and evasive flight, 
and fast and deep dives help this species to avoid aerial and mammalian 
predators at their nests or on the water. Because this species 
apparently has evolved a variety of behavioral strategies to evade 
their predators, few apparent situations may arise that could alter 
predation rates and result in a population- or species-level impact to 
the Kittliz's murrelet. However, this is a complex issue that involves 
both direct and indirect relationships (Hipfner et al. 2011, p. 41) and 
therefore it can be difficult to quantify impacts beyond the individual 
level. For example, increases in predator abundance could result in 
increased predation rates on Kittlitz's murrelets, but only if those 
predators were specializing on or targeting Kittlitz's murrelet as prey 
and not taking advantage of other suitable prey species. Such increases 
in predator abundance may be possible if predators were able to 
colonize previously unoccupied space, although at some threshold, 
density-dependent factors would likely prevail and predator numbers 
would stabilize. Predator-prey relationships are multi-faceted; 
increases in predators do not necessarily translate to decreases in 
prey.
    We assessed two types of predation that affect individual adult and 
juvenile Kittlitz's murrelets, but are often executed by a different 
suite of predators. We considered nest predation as an event that 
results in an egg or nestling being killed by a predator at the nest, 
and active predation to be an event that results in an adult or 
juvenile being killed away from the nest, but perhaps in transit to or 
from the nest. Likely nest predators include birds and mammals that 
occur or forage near the remote nest sites of the Kittlitz's murrelet 
(Day et al. 1999, p.12); confirmed nest predators of Kittlitz's 
murrelet eggs and nestlings are red fox (Lawonn 2012, p. 31), snowy owl 
(Bubo scandiacus) (Kaler, unpublished data), and common raven (Corvus 
corax) (Kenney 2012, in litt.). Likely active predators include raptors 
that have the ability to capture Kittlitz's murrelets in flight or on 
the water (Day et al. 1999, p.12); confirmed active predators are bald 
eagle and peregrine falcon (Falco peregrinus) (Arimitsu et al. 2010, p. 
15; Allyn 2012, p. 101; Kissling, unpublished data).
    Of the areas where Kittlitz's murrelet nests have been monitored 
regularly, nest predation appears to be a significant cause of nest 
failure at Kodiak Island and, to a lesser extent, the Aleutian Islands, 
but not in Icy Bay (see Reproductive Performance, above, for a full 
description). On Kodiak Island between 2008 and 2012, 53 percent of 
nest failures (29 of 55 failed nests) were attributed to depredation of 
egg or nestling, and red fox was identified as the nest predator at 87 
percent (13 of 15 nests) of the nests monitored with cameras (Corcoran 
and Mackey 2012, p. 3; Lawonn 2012, pp. 30-31, 59). On Agattu Island 
between 2006 and 2011, only 25 percent of the nest failures (18 of 72 
failed nests) was caused by depredation with the only identified 
predator at one nest being a snowy owl (Kaler, unpublished data), but 
common raven and glaucous-winged gull were implicated as the most 
likely nest predators because no terrestrial mammals occur on the 
island and these two species were commonly observed near Kittlitz's 
murrelet nests (Kaler and Kenney 2008, p. 15; Kaler et al. 2009, p. 
365). In 2012, on Adak Island, depredation was confirmed at only one 
nest (four nests failed due to unknown causes) when a common raven 
removed the egg from the nest (Kenney 2012, in litt.). In Icy Bay, most 
of the discovered nests were not accessible to humans due to dangerous, 
heavily glaciated terrain and therefore were monitored remotely. Only 
five nests were monitored directly in this area, and no predation 
events were observed, but it is very unlikely that nest predation 
commonly occurs in Icy Bay because the majority of suitable nesting 
habitat is remote and isolated from most potential nest predators, 
perhaps contributing to nest site selection by Kittlitz's murrelets 
(Kissling, unpublished data). As described under Factor B above, 
possible researcher impacts did not influence predation rates observed 
at monitored nests. Thus, it appears that in some parts of this 
species' range, nest predation is a substantial factor contributing to 
the poor reproductive performance of the Kittlitz's murrelet, but it is 
difficult to put this result into broader spatial and temporal context 
because the available data are too limited.
    Active predation on Kittlitz's murrelets is more challenging to 
document and quantify compared to nest predation because it is rarely 
observed, and, therefore, most information comes from studying the diet 
of probable or confirmed active predators. The diet of coastal breeding 
peregrine falcons is overwhelmingly dominated by alcids (e.g., auklets 
and murrelets), which comprise 75 percent of their diet (Beebe 1960, p. 
168; White et al. 1973, p. 307; Nelson and Myers 1976, p. 290), and 
procellarids (e.g., storm-petrels and shearwaters) similar in size to 
the Kittlitz's murrelet (White et al. 2002, p. 11). In contrast, the 
bald eagle is a generalist predator that consumes a high proportion of 
fish, but supplements its diet with other types of prey (e.g., birds), 
especially during times of the year when fish are not locally available 
(Buehler 2000, pp. 9-10); in some areas, however, birds can comprise a 
large proportion of eagle diet (Anthony et al. 2008, p. 2730; 
summarized in Hipfner et al. 2011, p. 42). In Russia, probable active 
predators include peregrine falcon, white-tailed eagle (H. albicilla) 
and Steller's sea eagle (H. pelagicus) (E. Potapov, Bryn Athyn College, 
2012, personal

[[Page 61790]]

communication), but likely only peregrine falcons prey on Kittlitz's 
murrelet with any frequency.
    In the rapidly changing, glaciated landscape of Icy Bay, Lewis 
(Service, 2007-2012, unpublished data) studied the diet and movements 
of nesting peregrine falcons and bald eagles with the goal of 
quantifying the scope and magnitude of active predation on the 
Kittlitz's murrelet. Movements of both predators overlapped 
considerably with areas frequently used by Kittlitz's murrelets. 
Individual peregrine falcons had large foraging ranges, including 
somewhat regular trips into upland areas of high suitability nesting 
habitat of the Kittlitz's murrelet; in fact, two radio-marked 
Kittlitz's murrelets were found dead at great distance from the water 
and were likely killed while in transit to and from their nest 
(Kissling, unpublished data). On the other hand, bald eagle movements 
were relatively constricted to the coast near their nesting areas; 
longer movements appeared to be driven by access to salmon spawning 
streams. Based on 544 prey remains (i.e., parts of prey removed before 
or left after consumption, such as feathers, bones, hair) collected at 
5 peregrine falcon nests over 6 years, Kittlitz's murrelet was the most 
commonly delivered prey species based on both frequency of occurrence 
(23 percent of prey remains) and biomass (26 percent). The biomass of 
Kittlitz's murrelet in peregrine falcon diet varied considerably among 
years (6-80 percent), which is likely partially related to sampling 
effort across years, but undoubtedly is also associated with annual 
changes in the availability of Kittlitz's murrelet, as well as 
differences in individual falcon hunting preferences. Conversely, bald 
eagles delivered very few Kittlitz's murrelets to their nests (n=6 
nests between 2007 and 2012); only 3 percent of prey remains (n=56) and 
1 percent of prey deliveries recorded using still cameras mounted above 
active nests were documented. These results are not surprising because 
the main seabird prey of bald eagles in Icy Bay and elsewhere includes 
species larger than the Kittlitz's murrelet (Hipfner et al. 2011, p. 
42; Lewis, unpublished data). Nonetheless, within Icy Bay, it appears 
that peregrine falcons are the primary active predator of Kittlitz's 
murrelets, and, at least in some years, falcons prey on this species at 
rates that could have an impact to the local population, especially 
because the predation results in adult mortality.
    The prevalence of Kittlitz's murrelet in the diet of peregrine 
falcons in Icy Bay may be due in part to the lack of alternative, 
appropriately-sized prey available to foraging falcons. In other 
coastal areas of Alaska, the marbled murrelet far outnumbers the 
Kittlitz's murrelet, and peregrine falcons likely prey on both species 
in proportion to their availability. Additionally, in areas where large 
seabird colonies exist (e.g., Kenai Fjords), peregrine falcons can 
select from seabirds similar in size to the Kittlitz's murrelet, such 
as ancient murrelet (Synthliboramphus antiquus), Cassin's auklet 
(Ptychoramphus aleuticus), and fork-tailed storm-petrel (Oceanodroma 
furcata). For example, in Kenai Fjords, peregrine falcon diet consisted 
of only 8 percent Brachyramphus murrelets (Phillips, National Park 
Service, 2012, unpublished data). In these areas, the impact to the 
local population of Kittlitz's murrelet from peregrine falcons would 
likely be much lower compared to an area like Icy Bay where few 
alternative prey are available. As glaciers recede, suitable cliff 
nesting and foraging habitat for peregrine falcons will become exposed, 
and falcons will likely colonize this newly created habitat, 
potentially having an impact on Kittlitz's murrelets that occupy the 
upper reaches of these fjords, but we anticipate any impact to be 
temporary, as alternative prey to falcons are also expected to colonize 
these areas (see Factor A discussion, above).
    The peregrine falcon is a far more efficient active predator 
compared to the bald eagle, and therefore, in areas where they coexist, 
bald eagles may alter predation rates of peregrine falcons by stealing 
captured prey items (i.e., kleptoparasitism) (Buehler 2000, p. 9), 
potentially increasing the number of Kittlitz's murrelets killed. 
Dekker and Bogaert (1997, pp. 381-383) observed 73 peregrine falcon 
foraging flights from Langara Island, British Columbia; only 22 percent 
of those flights resulted in the falcon returning to the island with 
prey, and on 13 percent of those flights, a bald eagle was actively 
pursuing the peregrine falcon. This behavior by bald eagles appeared to 
result in greater kill rates of peregrine falcons in order to 
compensate for prey lost to theft (Dekker et al. 2012, p. 293). There 
are observations and anectodal evidence of similar interactions between 
peregrine falcons and bald eagles in glacial fjords of Alaska, 
suggesting that kleptoparasitism may be altering peregrine kill rates 
in these areas as well, potentially having an effect on Kittlitz's 
murrelets.
    We know little about predation risk to Kittlitz's murrelets outside 
of the breeding season when at least some proportion of the global 
population occupies open leads and polynyas in the Bering and Chukchi 
seas (see Habitat and Life History, above). Recently, satellite 
tracking studies of gyrfalcons (F. rusticolus) and snowy owls found 
that these species spend considerable time during the winter months on 
sea ice, near polynyas, presumably preying on seabirds (Burnham and 
Newton 2011, p. 478; Therrien et al. 2011, p. 364). Because no data 
exist, we have no way of evaluating this potential threat to the 
Kittlitz's murrelet, but we assume that Kittlitz's murrelets likely 
experience risk of predation outside of the breeding season in addition 
to the actual predation during the breeding season described above.
    Because predation is a natural process, it is difficult to evaluate 
it as a population- or species-level threat to the Kittlitz's murrelet. 
We considered possible changes in distribution and abundance of nest 
and active predators and factors potentially contributing to those 
changes. We focused our evaluation on bald eagles and peregrine falcons 
because active predation often results in adult mortality of Kittlitz's 
murrelets, which can have a greater immediate influence on local 
population stability than failed reproductive attempts (Kissing, 
unpublished data).
    Populations of bald eagle have fluctuated over the last century due 
to human-caused influences (Buehler 2000, p. 1). In Alaska and British 
Columbia, bald eagles were targeted through an official bounty program 
because of their competition with fisheries (Hodges 2011, p. 7). In 
Alaska alone, 128,273 bounties were paid to hunters between 1917 and 
1953 (Robards and King 2004, p. 158), undoubtedly reducing the 
population of bald eagles, but persecution of this species ended with 
Statehood in 1959 (Hodges 2011, p. 7). By the 1980s, eagle populations 
began to recover and have increased or continue to increase since then, 
probably reaching carrying capacity throughout much of their range that 
overlaps with the Kittlitz's murrelet (Zwiefelhofer 2007, p. 8; Hodges 
2011, p. 10). Current distribution of bald eagles and Kittlitz's 
murrelets overlaps along most of south-coastal Alaska and the Aleutian 
Islands (Buehler 2000, p. 1). Bald eagles rarely occur along the coast 
north of the Alaska Peninsula, but do occur inland along rivers, where 
Kittlitz's murrelets are absent. There are no data to document bald 
eagle colonization rates of glacial fjords following glacial recession, 
but the best available information suggests that bald eagles inhabit 
these areas as suitable trees for large eagle nests become available 
and often nest at the leading

[[Page 61791]]

edge of tree line within the glacial fjord system (Lewis, unpublished 
data).
    Peregrine falcons nest throughout the range of the Kittlitz's 
murrelet (White et al. 2002, p. 1). Since severe population declines in 
the mid-1900s across North America (Kiff 1988, p.126; Enderson et al. 
1995, p.144), including some populations in Alaska (Ambrose et al. 
1988, p. 81), peregrine falcons have recovered to what is believed to 
be pre-decline numbers (White et al. 2002, p. 2). The cause of the 
decline was exposure to persistent chemicals that were commonly used in 
parts of the winter range of the peregrine falcon (White et al. 2002, 
p. 1). Because coastal peregrine falcons in Alaska were considered to 
be residents, it was generally assumed that the coastal population was 
not impacted and did not decline; however, recent evidence indicates 
that at least some coastal peregrine falcons overwinter in Central or 
South America (Lewis, unpublished data) and therefore may have 
experienced the same population declines and recovery. Nonetheless, 
information about peregrine populations within the range of the 
Kittlitz's murrelet is sparse and inconsistent. Recent surveys have 
found peregrines nesting in many areas where Kittlitz's murrelets occur 
and often in close association with seabird colonies (Hughes and Sanger 
1999, pp. 1-2; Shook and Ritchie 2011, p. 12). The only information 
available on changes in peregrine falcon numbers within the range of 
the Kittltiz's murrelet was collected in the glacial fjords of Icy Bay; 
in 1992 and 1995, despite considerable effort, no nesting peregrine 
falcons were located (Kozie 1993, pp. 5-6; Kozie et al. 1996, pp. 4-5), 
but between 2007 and 2012, five peregrine falcon nesting areas were 
occupied regularly (Lewis, unpublished data). This apparent increase 
may reflect overall recovery of peregrine falcons, as well as expansion 
into formerly unsuitable nesting and foraging habitat (e.g., recently 
deglaciated cliffs above open water). Regardless, we cannot project the 
possible implications of this anecdotal observation in Icy Bay to the 
Kittlitz's murrelet at the population or species level.
    The distribution and abundance of nest predators may have changed 
locally as the result of human actions and habitat conditions. We 
collated data on accidental introductions and game transplants across 
the range of the Kittlitz's murrelet using a variety of sources (Paul 
2009; Threatened Island Biodiversity Database 2013 [online]; Ebbert, 
Service, pers. comm.). Potential impacts to the Kittlitz's murrelet 
from nonnative introductions or transplants include direct predation at 
nests and availability of alternate prey for nest predators. Since the 
early 1900s, 174 introductions and transplants have occurred within the 
range of the Kittlitz's murrelet and most of these were fox (n=48; 
Vulpes spp.), rat (n=20; Rattus spp.), and rabbit (n=17; Lepus spp.) 
with the latter primarily introduced for fox food. Eradication efforts 
have been successful, especially on many of the Aleutian Islands, but 
may have had some impact on nesting Kittlitz's murrelets prior to 
eradication, expecially fox. We overlaid remaining nonnative species 
distributions with the Kittlitz's murrelet nest habitat suitability map 
(described in Nesting, above) and identified nine islands (Afognak, 
Kodiak, Attu, Amchitka, Adak, Great Sitkin, Atka, Unalaska, and Akutan 
islands) where introduced or transplanted species may be having an 
indirect impact to Kittlitz's murrelet, primarily by enhancing prey 
abundance for native species that are nest predators. For example, 
while red fox, a known nest predator to the Kittlitz's murrelet (Lawonn 
2012, p. 31), is native to Kodiak Island, several species that it can 
prey upon or scavenge have been introduced, including Sitka black-
tailed deer (Odocoileus hemionus sitkensis), red squirrel (Tamiasciurus 
hudsonicus), snowshoe hare (Lepus americanus), American marten (Martes 
americana), mountain goat (Oreamnos americanus), Roosevelt elk (Cervus 
canadensis roosevelti), reindeer (Rangifer tarandus), and beaver 
(Castor canadensis). Although historical and current fox population 
abundance are not known, it seems likely that introductions increased 
the carrying capacity of fox on Kodiak Island by providing additional 
sources of food, and this increased carrying capacity potentially has 
negative effects on nesting Kittlitz's murrelets. We have no data to 
support this hypothesis or to assess potential impacts to the local 
population of Kittlitz's murrelet. Unfortunately, there is no at-sea 
population trend information for the Kittlitz's murrelet near Kodiak 
Island (Madison et al. 2011, p. 118) or in the vicinity of other 
islands with relatively large number of introductions or transplants. 
Similarly, other human activities may have cascading consequences that 
can impact the Kittlitz's murrelet, such as refuse from seafood 
processing, which is known to attract several gull species (Yorio and 
Caille 2004, p. 778; Gibson and Byrd 2007, pp. 136-137; Carniel and 
Krul 2012, p. 61), and bald eagles (Lewis, unpublished data), but we 
have no information to suggest that these artificial increases in local 
populations of nest predators actually translate into increased 
predation of Kittlitz's murrelet.
Conservation Efforts To Reduce Disease or Predation
    We are not aware of any conservation efforts or other voluntary 
actions that may help to reduce disease or predation of the Kittlitz's 
murrelet.

Summary of Factor C

    In summary, based on the available information, we find that 
disease is not a threat to the Kittlitz's murrelet now or is likely to 
be one in the future. Biotoxins, or harmful algal blooms, are likely 
the cause of small numbers of mortalities of individual Kittlitz's 
murrelets, but we do not have information to suggest that biotoxins are 
having a population- or species-level impact on the Kittlitz's 
murrelet.
    Predation is a source of mortality of Kittlitz's murrelet eggs, 
nestlings, and adults. Although behavioral or morphological strategies 
against predation have been identified for all life-history stages of 
this species, it is clear that predation and risk of predation is a 
regular occurrence. It appears that predation rates may be elevated in 
certain locations as a result of human actions or consequences of 
climate change, but negative impacts to the Kittlitz's murrelet seem to 
be localized. Thus, based on the information available, we find that 
predation in and of itself is not a threat to this species, nor is it 
likely to become a threat in the future.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    Several laws have been passed that help maintain the quality of 
habitat that Kittlitz's murrelets occupy and reduce threats to those 
habitats. We determined that the existing regulatory mechanisms 
authorized by these laws are adequate for the Kittlitz's murrelet. 
These laws are discussed briefly below.
Oil Pollution Act (OPA) of 1990
    The Oil Pollution Act of 1990 (OPA) (33 U.S.C. 2701 et seq.) 
provides enhanced capabilities for oil spill response and natural 
resource damage assessment by the Service. The OPA and implementing 
regulations require 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

[[Page 61792]]

the restoration of natural resources injured from oil spills. In 
addition, the OPA includes provisions for the double-hulling of oil 
tankers; all new tankers are required to be double-hulled, and single-
hulled tankers will be phased out completely and replaced with double-
hulled tankers by 2015. The double-hulling provision within the OPA 
should reduce the likelihood of marine hydrocarbon contamination due to 
accidents within the range of the Kittlitz's murrelet.
Coastal Zone Management Act (CZMA)
    The Coastal Zone Management Act of 1972 (CZMA) (16 U.S.C. 1451 et 
seq.) was enacted to preserve, protect, develop, and where possible, 
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. In 2011, the Alaska Legislature did 
not renew the State of Alaska's program, and it was phased out by the 
Alaska Department of Natural Resources. Thus, Alaska has not had an 
active Coastal Management Program since 2011.
Marine Protection, Research and Sanctuaries Act (MPRSA)
    The Marine Protection, Research and Sanctuaries Act of 1972 (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 
was designed to protect the quality of marine habitats that the 
Kittlitz's murrelet and its prey utilize.
Migratory Bird Treaty Act
    Although the Migratory Bird Treaty Act (16 U.S.C. 703 et seq.) 
prohibits, unless permitted by regulation, any take of any migratory 
bird, including Kittlitz's murrelet, such incidental take does occur in 
commercial fisheries in Alaska (Wynne et al. 1991, pp. 25-31; Wynne et 
al. 1992, pp. 18-19; Stehn et al. 2001, pp. 68-70; Manly 2007, p. 90; 
Manly 2009, p. 66). Murrelets do not appear to be taken by longliners, 
by trawlers, or within pot fisheries (Stehn et al. 2001, p. 71; 
Phillips et al. 2010, p. 113). However, where studies have examined 
seabird bycatch in nearshore gillnet fisheries in the range of 
Kittlitz's murrelets, Brachyramphus murrelets (marbled and Kittlitz's 
combined) comprise between 11 and 70 percent of seabird mortality from 
gillnets (Wynne et al. 1991, p. 33; Wynne et al. 1992, p. 49; Carter et 
al. 1995, pp. 271-275; Manly 2006 p. 31; Manly 2007, pp. 34-35; Manly 
2009, pp. 31-32). Gillnet bycatch is an ongoing source of mortality to 
Kittlitz's murrelets (see Incidental Take in Fisheries, below), but 
Blejwas and Wright (2012, p. 14) concluded that fine scale spatial 
overlap of Kittlitz's murrelet distribution and commercial gillnet 
fishing effort was low. Gillnet fisheries in Alaska generally occur in 
State territorial waters. Melvin et al. (1999, pp. 1389-1396) reported 
on gear types and fishing methods that reduce such bycatch, but 
regulations requiring the use of bycatch reduction techniques are not 
currently in place.
State Regulations
    In 2013, the Alaska State Legislature passed a bill to allow cruise 
ships to meet water quality standards at the ends of a mixing zone, as 
opposed to the point of discharge, relaxing water quality standards 
within the marine environment. However, it is unlikely that this will 
have a negative impact on the Kittlitz's murrelet because, considering 
the broad range of the species, the spatial and temporal overlap 
between the Kittlitz's murrelet and cruise ships is low, except in 
Glacier Bay National Park where the marine waters are federally managed 
and discharge is not allowed.
    The Kittlitz's murrelet receives no special protection by the State 
of Alaska. On March 5, 2009, the Center for Biological Diversity (CBD) 
petitioned the State of Alaska to list the Kittlitz's murrelet as 
endangered under the Alaska Endangered Species Act (A.S. 16.20.180 et 
seq.). The petition specified that because of the species' small 
population size, precipitous population declines, and multiple, ongoing 
threats to its continued existence, the Kittlitz's murrelet should 
receive State-level regulatory protection. On April 9, 2009, the State 
rejected CBD's petition to list the Kittlitz's murrelet as endangered 
under the Alaska Endangered Species Act, claiming insufficient evidence 
to indicate that their numbers have decreased to the extent to cause 
endangerment.

Summary of Factor D

    The laws described above reduce the likelihood of oil spills, help 
protect water quality in marine habitats, and prohibit take of 
Kittlitz's murrelet unless permitted by regulation. Through such 
actions, these laws provide some protection to the Kittlitz's murrelet 
and its habitats. As discussed in Factors A, B, C, and E, although we 
recognize that some of the potential stressors addressed may result in 
mortality of individual Kittlitz's murrelets, we have not identified 
any threat that would affect the species at the population or range-
wide level. Therefore, we find that the existing regulatory mechanisms 
authorized by the laws described above are adequate for the Kittlitz's 
murrelet now and into the future.

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

Recreational Effects
    The Kittlitz's murrelet is rarely pursued by commercial tour boat 
operators or recreational vessels, but the scenic tidewater glacier 
habitat in which this species occurs in parts of its range is often the 
ultimate destination for these users. Marine and coastal tourism has 
increased substantially over the last few decades in many areas that 
have relatively dense populations of the Kittlitz's murrelet during the 
breeding season (see Habitat and Life History, above), including 
Glacier Bay, Yakutat Bay, Prince William Sound, and Kenai Fjords (Day 
et al. 1999, pp. 20-21; Jansen et al. 2006, p. 1186; Payne et al. 2010, 
p. 7; Hoover-Miller et al. 2013, p. 3). Motorized and non-motorized 
vessels can impact marine wildlife directly (e.g., injury or mortality 
due to collision) (Jensen and Silber 2003, p. 2; Neilsen et al. 2012, 
p. 1) or indirectly (e.g., disturbance) (Jansen et al. 2010, p. 1186; 
Schwemmer et al. 2011, pp. 1855-1857; Hoover-Miller 2012, pp. 8-9). It 
is extremely unlikely that Kittlitz's murrelets are directly impacted 
by vessel activity owing to their ability to flush from the water if 
within a vessel pathway and their skillful maneuverability during 
flight. In the fjords of northwestern Prince William Sound, jet-
propulsion tour catamarans can travel at speeds up to 42 mi per hour 
(68 km per hour), ingesting water and debris down to 20 ft (6 m) below 
the water surface, and murrelets diving in the path of these boats may 
not be able to escape injury (Kuletz, pers. obs.), although it has 
never been documented. Indirect impacts to individuals may include 
increased energetic costs (Speckman et al. 2004, p. 33; Agness et al. 
2013, p. 13), increased predation risk (Whittington 2008, in litt.), 
temporary changes to foraging habitat characteristics (Kuletz et al. 
2003a, pp. 23, 29; Stephensen 2009, p. 22), displacement of murrelets 
(Kuletz 1996, pp. 777-778; Stephensen 2009, pp. 22-23; Agness et al. 
2008, p. 352), and

[[Page 61793]]

reduced ability to feed (Day et al. 2003, p. 697).
    Several studies in Alaska have attempted to understand the scope 
and magnitude of possible effects to Kittlitz's murrelets from vessel 
activity and to develop guidelines to minimize any impacts. In all 
areas studied, Kittlitz's murrelets and vessel traffic overlap 
spatially (typically within the glacial fjords) and temporally (May-
July). In Prince William Sound, the number of murrelets observed on the 
water was negatively correlated with the number of boats in the area 
(Kuletz 1996, pp. 777-778; Kuletz et al. 2003a, pp. 23, 25) and 
densities of murrelets decreased between the initial and return boat 
transits in one of the glacial fjords of the area (Stephensen 2009, pp. 
22-23). During a pilot study using focal-animal observations in two 
fjords of Prince William Sound, birds conducted fewer forage dives and 
flew away more often in the presence of boats, and flushing distance 
was estimated at 82-1,640 ft (25-500 m) (Kuletz et al. 2003a, pp. 23, 
29). Because Kittlitz's murrelets tended to occupy the mid-water 
channels where boat traffic was greatest, there was potential for 
vessel disturbance during the summer months (Kuletz et al. 2003a, pp. 
29-30). There may be a vessel density threshold beyond which murrelets 
may not occupy an area, as reported by Day et al. (2003, p. 697), but 
this theory has not been tested. Schoen et al. (2013, pp. 56-57) took a 
different approach and quantified spatial overlap of Kittlitz's 
murrelets and vessels in Yakutat Bay. The average probability of an 
individual Kittlitz's murrelet encountering a vessel at least once per 
day was extremely low (0.0097; SE=0.0031), and the proportion of the 
local population disturbed daily was 0.98 percent (roughly 23 
individuals); for comparison, the same values for marbled murrelet were 
0.0083 (SE=0.0013) and 0.83 percent (roughly 76 individuals) (Schoen et 
al. 2013, p. 59). Although all of these studies document encounters and 
temporary displacement of individual Kittlitz's murrelets in response 
to vessel activity, none provides evidence of a measurable demographic 
response at the individual, population, or species level. Marbled 
murrelets showed a tendency to swallow fish held at the surface 
(presumably for their chicks) when disrupted by boat traffic (Speckman 
et al. 2004, p. 33), which may have unmeasurable implications for birds 
raising chicks, but there is no evidence to support this supposition.
    The most comprehensive and targeted studies to evaluate effects of 
vessel activity on Kittlitz's murrelets were conducted in Glacier Bay. 
Agness et al. (2008, p. 352) reported that nearshore densities of 
murrelets decreased temporally following vessel passage, but recovered 
within the day, concluding that vessel activity does not constitute a 
loss of suitable habitat for the Kittlitz's murrelet. Environmental and 
biological factors had more influence on density, group size, and 
behavior of Kittlitz's murrelets than vessel activity (Agness et al. 
2008, p. 351). However, vessel passage, especially large, fast-moving 
vessels, did cause a 30-fold increase in flight behavior of Kittlitz's 
murrelets observed nearshore (Agness et al. 2008, p. 346), which 
resulted in a 10-50 percent increase in daily energy expenditure of 
individual murrelets (Agness et al. 2013, p. 13). Bioenergetic modeling 
suggested that, in the absence of vessel disturbance, Kittlitz's 
murrelets need to consume about 76 percent of their body mass daily, 
but with vessel disturbance, this increased to 83-107 percent depending 
on breeding status and rate of vessel passage; presumed non-breeding 
Kittlitz's murrelets were more likely to experience chronic increases 
in energy expense compared to breeding birds because they have more 
flexible activity budgets (Agness et al. 2013, p. 18). The authors 
concluded that Kittlitz's murrelets may have a relatively small 
capacity to buffer extra energy demands because they may already be 
functioning at their physiological limits (Agness et al. 2013, p. 18). 
A follow-up study to refine time activity budgets of Kittlitz's 
murrelets, especially those found offshore and in the direct path of 
large vessels, is currently being conducted (Marcella et al. 2012, p. 
1). Preliminary results indicate that roughly half of all murrelets 
observed within 0.5 mi (0.8 km) of a vessel path were disturbed, and 
the proportion of birds to take flight in response to the vessel was 
greater than 50 percent within 656 ft (200 m) of the vessel, but 
declined thereafter (Marcella et al. 2012, pp. 7, 15). In both years of 
the study, mean flushing distance of Kittlitz's murrelet (2011=830 ft 
[253 m], 2012=1,027 ft [313 m]) was smaller than that of marbled 
murrelet (2011=1,158 ft [353 m], 2012=1,266 ft [386 m]), but this 
result could be related to species-specific identification rates 
(Marcella et al. 2012, p. 11). Neither of these studies evaluated 
potential energetic effects to individual Kittlitz's murrelets that are 
displaced by vessels multiple times per day or continually throughout 
the season.
    Among all core areas that support Kittlitz's murrelets in the 
breeding season, Icy Bay is the only glacial fjord system that remains 
relatively free of commercial and recreational boat traffic. Perhaps 
coincidentally, this is the only area where Kittlitz's murrelet 
outnumbers marbled murrelet by a factor of at least two across all 
years (Kissling et al. 2011, p. 7; Kissling, unpublished data). This 
unique composition of Brachyramphus murrelets is very likely due to 
site-specific environmental conditions, not the absence of 
anthropogenic effects, but we cannot disregard it, especially because 
in nearby Yakutat Bay with moderate levels of boat traffic (Schoen et 
al. 2013, p. 59), marbled murrelet abundance is more than double 
Kittlitz's murrelet abundance (Kissling et al. 2011, p. 7).
Incidental Take in Fisheries
    Globally, seabird bycatch is one of the most pervasive and 
immediate threats to many pelagic species, affecting 41 percent of all 
seabirds species listed as threatened by the International Union for 
the Conservation of Nature (Croxall et al. 2012, p. 10). Commercial, 
recreational, and subsistence fisheries occur in coastal Alaska and 
Russia within the range of the Kittlitz's murrelet. Owing to their 
nearshore feeding and pursuit-diving behavior to forage, murrelets are 
particularly susceptible to mortality in gillnet fisheries. Incidental 
take of Kittlitz's murrelets has been documented in the salmon gillnet 
fisheries in Alaska (Wynne et al. 1991, p. 33; Wynne et al. 1992, p. 
49; Manly 2007, p. 33; Manly 2009, p. 4), subsistence gillnet fisheries 
in Russia (Artukhin 2011, p. 7; Artukhin et al. 2011, p. 28), and in 
offshore Japanese salmon drift nets (Artukhin et al. 2011, p. 31). No 
studies have aimed specifically to quantify gillnet mortality rates of 
Kittlitz's murrelet, so data are limited to existing observer programs, 
most of which are implemented to record interactions and take of marine 
mammals in gillnet fisheries, and consist of questionnaires distributed 
to fishermen and local villagers.
    In Alaska, data have been collected on incidental take of marine 
mammals and birds in gillnet fisheries in 4 areas for 2 years each: 
Prince William Sound and Copper River Delta (1990, 1991), Cook Inlet 
(1999, 2000), Kodiak Island (2002, 2005), and Yakutat Bay (2007, 2008). 
Not accounting for observer effort and number of boats monitored, nine 
adult Kittlitz's murrelets and three unidentified murrelets were killed 
in Prince William Sound and Copper River Delta (Wynne et al. 1991, p. 
33; Wynne et al. 1992, p. 49), zero Kittlitz's or unidentified 
murrelets in Cook Inlet

[[Page 61794]]

Inlet (Manly 2006, p. 73), one juvenile Kittlitz's murrelet near Kodiak 
Island (Manly 2007, pp. 27, 33), and one adult Kittlitz's murrelet and 
one unidentified murrelet near Yakutat (Manly 2009, pp. 29-30). 
Although these numbers appear to be small, only about 5 percent of the 
total fishing effort is typically sampled (Manly 2009, p. 3), which is 
likely insufficient to estimate bycatch rates of rare species. 
Recognizing the limitations of these data due to low sampling effort, 
estimated per annum incidental catch of Kittlitz's murrelets was 133 
birds in Prince William Sound (Wynne et al. 1992, p. 48), zero in Cook 
Inlet (Manly 2006, p. 73), 18.1 birds (SE=16.8) near Kodiak Island 
(Manly 2007, p. 36), and 13.7 birds (SE=12.9) in Yakutat Bay (Manly 
2009, p. 34). The high variances around the estimates for Kodiak Island 
and Yakutat Bay reflect both low sampling effort and the relatively low 
densities of Kittlitz's murrelets at sea.
    In some areas, Brachyramphus murrelets appear to be 
disproportionately caught in nets of these fisheries compared to other 
marine birds (Wynne et al. 1991, p. 33; Wynne et al. 1992, p. 49; Manly 
2009, pp. 31-32), as suggested by Day et al. (1999, p. 17). Combining 
the limited bycatch data described above with information on murrelet 
and fishing vessel distribution, Blejwas and Wright (2012, p. 2) 
completed a qualitative risk assessment by determining spatial and 
temporal overlap of Kittlitz's murrelets and gillnet fishing effort. 
Temporal overlap between Kittlitz's murrelets and gillnet fisheries was 
high, but the degree of spatial overlap varied by scale (Blejwas and 
Wright 2012, p. 14). At a coarse scale, generally within a bay, inlet, 
or defined set of coastline, there was moderate overlap, but at a finer 
scale, Kittlitz's murrelets were spatially separated from gillnet 
fisheries with a few exceptions (e.g., Alitak Bay near Kodiak Island, 
Manby Point near Yakutat) (Blejwas and Wright 2012, pp. 14-15). While 
this approach provided the first assessment of the potential magnitude 
of gillnet fishery impacts to Kittlitz's murrelets, it clearly has some 
limitations such as the inability to account for intra- and inter-
annual variation in murrelet and vessel distribution (Blejwas and 
Wright 2012, p. 16), and the scope of inference is restricted to 
daytime hours only when surveys for murrelets were completed (Blejwas 
and Wright 2012, pp. 17-18). Despite these limitations and the reported 
low overlap of Kittlitz's murrelets and gillnet fishing effort, bycatch 
mortalities did occur, and, therefore, gillnets are a source of direct 
mortality to some individual Kittlitz's murrelets. Carter (2012, p. 3) 
clarified previous reports of Brachyramphus murrelet mortalities in 
gillnet fisheries in Alaska and concluded that Kittlitz's murrelets 
were spatially separated from concentrations of fishing boats and 
appeared to have greater net avoidance compared to marbled murrelets.
    There are comparatively fewer data on incidental take of Kittlitz's 
murrelet in Russian fisheries, but mortalities have been documented 
(Artukhin 2011, p. 7; Artukhin et al. 2011, p. 28). In the Kamchatka 
region, marine trap nets are the primary method used in the commercial 
coastal salmon fishery, constituting 95 percent of the total harvest 
(Artukhin 2011, p. 7). Owing to the design and operation of these nets, 
risk of entanglement of birds is low, and, in fact, no bycatch 
mortality of Kittlitz's murrelets was documented during the observer 
program and is not considered to be a concern in this area (Artukhin 
2011, p. 7). However, along the Chukotka Peninsula, different fishing 
gear and methods are used in the subsistence fishery near coastal 
villages, resulting in three Kittlitz's murrelets being caught in 
fishnets used by native people in 1971 (Artukhin et al. 2011, p. 28). 
It is unknown if this is a continuing occurrence in this region, but it 
seems likely.
    In some areas, gillnet fishing can occur at all times of day and 
may interact with individual Kittlitz's murrelets during the night 
(Allyn 2012, p. 104). However, within glacial fjords and bays, 
Kittlitz's murrelets rapidly exit daytime locations at dusk and shift 
to deeper waters farther from shore where they remain throughout the 
night (Kissling, unpublished data). Furthermore, Kittlitz's murrelets 
typically forage during the day (Day et al. 1999, p. 9; Madison et al. 
2010, p. 1), especially in the morning (Day and Nigro 2000, p. 5), 
which reduces potential for interactions between Kittlitz's murrelets 
and gillnets at night. Nonetheless, Carter (2012, p. 2) reported an 
observation from a fisherman suggesting that most Brachyramphus 
mortalities (80 percent) in gillnets occurred at night, but there is no 
evidence to substantiate this statement.
    We know little about potential overlap of the Kittlitz's murrelet 
and the North Pacific high-seas driftnet fishery. Artukhin et al. 
(2011, p. 31) reported that bycatch of Kittlitz's murrelet in Japanese 
salmon drift nets was estimated to be about 1 bird per year (95 percent 
CI=0-2). Generally, offshore mortality of Brachyramphus murrelets is 
not recognized as a significant problem (Ainley et al. 1981, p. 803; 
DeGange and Day 1991, p. 253; Johnson et al. 1993, p. 473; Carter et 
al. 1995, p. 275), but does occasionally occur.
Conservation Efforts To Reduce Other Natural or Manmade Factors 
Affecting Its Continued Existence
    The Service and the National Marine Fisheries Service entered into 
a memorandum of understanding (MOU) in June 2012 with the overall 
purpose to conserve migratory birds (per Executive Order 13186, 
``Responsibilities of Federal Agencies to Protect Migratory Birds'') 
(National Marine Fisheries Service 2012, [http://www.alaskafisheries.noaa.gov/protectedresources/seabirds/mou/eo13186_nmfs_fws_mou2012.pdf, accessed on July 11, 2013]). Specifically, the 
MOU promotes a partnership between the two agencies to minimize the 
unintentional take of seabirds in commercial fisheries nationally and 
internationally. Although the primary focus is reducing bycatch of 
seabirds in longline gear, other gear types (e.g., gillnet fisheries) 
more likely to impact the Kittlitz's murrelet are also included.
    We are not aware of any other conservation efforts or other 
voluntary actions that may help to reduce or ameliorate other natural 
or manmade factors that may be a threat to the continued existence of 
the Kittlitz's murrelet.

Summary of Factor E

    To summarize, collectively, results of the vessel disturbance 
studies demonstrate that Kittlitz's murrelets do respond to vessels, 
including those at great distances from them, and that there may be 
increased energetic costs to individuals as a consequence, but 
displacement is temporary and encounter rates are low. It is 
challenging to assess vessel activity and disturbance as a possible 
threat to the Kittlitz's murrelet because there is no evidence to 
suggest that there are fitness impacts, such as reduced nest success or 
survival, affecting population(s) or even individual Kittlitz's 
murrelets. In addition, vessel activity is relatively limited in scope 
geographically and seasonally, and some individual murrelets may 
habituate to boat traffic (Speckman et al. 2004, pp. 32-33). Therefore, 
we conclude that vessel disturbance may be an additive stressor to some 
individual Kittlitz's murrelets, but we conclude that it currently does 
not pose a population- or species-level threat to the Kittlitz's 
murrelet, nor is it likely to become a threat in the future.
    Commercial and subsistence gillnets are a known source of mortality 
of individual Kittlitz's murrelets. Although

[[Page 61795]]

temporal overlap of gillnet fishing and distribution of this species is 
high, spatial overlap is currently low (Blejwas and Wright 2012, pp. 
14-15). At a coarse scale, gillnet fishing effort overlaps 
significantly with Kittlitz's murrelet distribution (Blejwas and Wright 
2012, p. 14), but the opposite is not necessarily true; the Kittlitz's 
murrelet is distributed across some nearshore marine waters where 
gillnet fishing does not occur, including Glacier Bay (Piatt et al. 
2011, pp. 68-69), Alaska Peninsula (Madison et al. 2011, p. 115), and 
Aleutian Islands (Madison et al. 2011, pp. 116-117). Furthermore, fine 
scale overlap of gillnet fishing and Kittlitz's murrelet distribution 
within a specific area is minimal (Blejwas and Wright 2012, pp. 14-15). 
As pursuit-divers that capture their prey underwater, Kittlitz's 
murrelets are susceptible to being caught in gillnets, but some aspects 
of their behavior and habitat use, such as moving to deeper water at 
night and perhaps net avoidance, may minimize their overall risk to 
gillnet mortality. Thus, although bycatch mortality of Kittlitz's 
murrelets does occur, we conclude that incidental take of indivduals in 
commercial, recreational, or subsistence fisheries is not a population- 
or species-level threat to the Kittlitz's murrelet, nor do we 
anticipate that it will become a threat in the future.

Cumulative Effects From Factors A through E

    The Kittlitz's murrelet is faced with numerous potential stressors 
throughout its range and its annual cycle, but none of these 
individually constitutes a threat to the species now or in the future. 
However, more than one stressor may interact synergistically or 
compound with one another to impact the Kittlitz's murrelet negatively 
at the population or species level. Not all of the identified possible 
threats described above are present or are equally present across this 
species' range or its annual cycle (e.g., incidental take in fisheries, 
vessel disturbance), and, in some cases, we were not able to determine 
the response of this species to the stressor because we lack a 
mechanistic link (e.g., loss of glaciers). For some of the identified 
stressors, we were unable to conclude that there would be a negative 
response of Kittlitz's murrelet at the population or species level to 
those stressors or changes in the frequency and intensity of them. Yet, 
if multiple factors are working together to impact the Kittlitz's 
murrelet negatively, the cumulative effects should be manifested in a 
measurable and consistent demographic change at the population or 
species level, but we did not determine this to be the case.
    Based on our analyses of population status and trend (see 
Population Status and Trends, above, for detailed summary), we 
concluded that Kittlitz's murrelet populations declined at about 30 
percent per annum prior to 2000 and since then, the populations appear 
to have stabilized or may be declining and are projected to continue to 
decline at a gradual, slow rate. In specific areas, such as Prince 
William Sound and Glacier Bay, declines in the Kittlitz's murrelet have 
been documented (Kuletz et al. 2011a, p. 104; Kuletz et al. 2011b, p. 
91; Piatt et al. 2011, p. 70) and disputed (Hodges and Kirchhoff 2012, 
p. 117; Kirchhoff et al. 2013, p. 10) or the reliability of data has 
been questioned (Day 2011, p. 51). We acknowledge that these local 
population declines likely occurred, but when evaluated as a whole, 
there is no credible evidence of a rangewide population decline in 
Kittlitz's murrelet since 2000, despite multiple stressors facing this 
species in all or parts of its range and annual cycle. Thus, the best 
available information suggests that cumulative effects from possible 
stressors described under Factors A through E above are not so great so 
as to pose a threat to the persistence of this species now or in the 
future.

Finding

    As required by the Act, we considered the five factors in assessing 
whether the Kittlitz's murrelet is an endangered or threatened species 
throughout all of its range. We examined the best scientific and 
commercial information available regarding the past, present, and 
future threats faced by the Kittlitz's murrelet. We reviewed the 
petition, information available in our files, other available published 
and unpublished information, and we consulted with recognized 
Kittlitz's murrelet experts and other Federal, State, and tribal 
agencies. We also requested comments and information from all 
interested parties in each of our CNORs from 2004 to 2011, and in 
preparation for this finding. In response to our request, we received 
formal comments from the Alaska Department of Fish and Game and CBD. We 
also convened a 1-day workshop to review the methods and interpretation 
of results of the multiple-populations model described above (see 
Population Status and Trends, above). As part of our review, we brought 
together researchers with experience and expertise in Kittlitz's 
murrelet biology from across the Service to review and evaluate the 
best available scientific and commercial information thoroughly at 
several meetings in Anchorage, Alaska.
    We considered a variety of potential threats facing the Kittlitz's 
murrelet and its marine and terrestrial habitats, including climate 
change, exposure to environmental contaminants and marine pollution, 
disease, changes in predation, disturbance from vessel traffic, and 
incidental take in fisheries. To determine if these risk factors 
individually or collectively put the species in danger of extinction 
throughout its range, or are likely to do so in the foreseeable future, 
we first considered if the identified risk factors were causing a 
population decline or other demographic changes, or were likely to do 
so in the foreseeable future.
    Boat-based surveys for Kittlitz's murrelets on the water during the 
breeding season are the most efficient method for estimating population 
size and trend of this species. Using the most current survey data 
available for each study site, we estimated the current global 
population of Kittlitz's murrelet to be 33,583 birds (95 percent 
CI=25,620-41,546), which is a minimum estimate because many areas 
within the range of this species remain unsurveyed. Estimating 
population trend of Kittlitz's murrelet is difficult because 
populations are geographically clustered, most individuals do not breed 
annually and therefore can be highly mobile during the breeding season 
when surveys are conducted, and the species looks similar to the more 
common marbled murrelet. These issues, coupled with inconsistencies in 
survey design and analysis, have complicated the use of historical data 
in trend estimation of local population size. Furthermore, there are 
few study sites that have been surveyed regularly enough to estimate 
local population trends reliably. Without accounting for intra- and 
inter-annual movements, apparent declines have been documented in local 
population size of Kittlitz's murrelet in some study sites over the 
last two decades. When all populations with sufficient years of data 
are evaluated collectively, Kittlitz's murrelet abundance declined by 
roughly 30 percent annually between 1989 and 2000, but populations 
appear to have stabilized since then.
    Although surveys indicate that the population of Kittlitz's 
murrelet stabilized between 2000 and 2012, several lines of evidence 
across a similar time frame suggest that reproduction of this species 
is poor. Both the number of birds that attempt to breed annually and 
the number that breed successfully are low with some variation among 
study sites and years. Only a few studies on

[[Page 61796]]

the Kittlitz's murrelet have estimated demographic parameters (e.g., 
breeding propensity, nest success, survival) necessary to identify key 
factors that may be influencing population stability and to predict 
future population size. We combined all demographic information 
available since 2000 for the Kittlitz's murrelet and concluded that 
populations will likely undergo a slow decline in the future of less 
than 2 percent annually, provided that environmental conditions and 
stressors remain the same on average. Using the multiple-populations 
model, we estimated that the probability of extinction in 25 years is 
less than 1 percent, but we are unable to project population size 
reliably beyond this timeframe. The model predictions of population 
size informed our assessment of the current and future status of this 
species along with the local populations information and our trend 
analysis. Therefore, based on the best available information, we find 
that population trend of Kittlitz's murrelet is currently either stable 
or possibly slightly declining.
    We then identified and evaluated existing and potential stressors 
on the Kittlitz's murrelet. We aimed to determine if these stressors 
are affecting this species currently or are likely to do so in the 
foreseeable future, are likely to increase or decrease, and may rise to 
the level of a threat to the species, rangewide or at the population 
level. Because this species is broadly distributed across Alaska and 
Russia, occupying numerous habitats throughout its annual cycle, we 
evaluated both exposure and response of Kittlitz's murrelets to each 
identified stressor.
    We examined several stressors that were temporally episodic, 
spatially localized, or both, relative to the seasonal distribution of 
the Kittlitz's murrelet. For some of these stressors, we have little 
information to assess their frequency or intensity now or in the 
foreseeable future or to indicate that the stressor is likely to 
increase in the foreseeable future. We found that disease, harmful 
algal blooms, incidental take in fisheries, disturbance from vessel 
activity, impacts from scientific research, or exposure to 
environmental contaminants are not threats to the Kittlitz's murrelet 
(see discussions under Factors A, B, C, and E, above). Although some of 
these stressors do result in mortality, risk, or increased energetic 
costs to small numbers of Kittlitz's murrelets, the best available 
information indicates that none of these stressors is currently having 
a population- or species-level effect, or is likely to do so in the 
foreseeable future.
    Climate change is occurring and is predicted to continue, but there 
is substantial uncertainty in the response of the Kittlitz's murrelet 
to possible environmental changes as a consequence of climate change. 
We considered loss of glaciers and winter sea ice, increased 
contaminated meltwater, and changes in ocean conditions as climate 
change stressors that may affect the persistence of the Kittlitz's 
murrelet and its habitats. Of these stressors, we were unable to 
evaluate the significance of glacial meltwater as a source of 
contamination and loss of winter sea ice to the Kittlitz's murrelet 
because few data exist. We are unaware of any contaminant studies from 
coastal ice fields or alpine glaciers within the range of the 
Kittlitz's murrelet, and information on winter distribution and habitat 
use of this species is too limited and preliminary to assess potential 
impacts of the loss of winter sea ice on the Kittlitz's murrelet. We 
therefore focused our evaluation of climate change stressors to this 
species on the loss of glaciers and changes in ocean conditions.
    Approximately 66 percent of the minimum global population of 
Kittlitz's murrelet occupy glacially affected marine waters during the 
breeding season, but we did not identify a causal link between the 
tidewater glaciers and persistence of the Kittlitz's murrelet. Several 
studies report associations between Kittlitz's murrelet marine 
distribution and tidewater glaciers in areas where glaciers exist, but 
this species is broadly distributed and occurs in areas that have been 
deglaciated for thousands of years. These rangewide inconsistencies in 
marine habitat use make it difficult to predict response of the 
Kittlitz's murrelet to the loss of glaciers without an identified, 
underlying mechanism explaining the association. We identified and 
evaluated many hypothetical consequences to this species and its 
viability due to loss of glaciers, such as changes in foraging 
efficiency, changes in marine productivity, and increasing distance 
between foraging and nesting sites, but none was supported with 
sufficient evidence, or the scope of inference and the available data 
were too limited to draw conclusions at the population or species level 
(see Factor A discussion for further details). We did not find 
information to indicate that Kittlitz's murrelets experience greater 
foraging success, or subsequent productivity or survival, in glacially 
affected waters compared to those without glacial influence. Thus, 
although most glaciers within the range of this species are currently 
in retreat or thinning, at this time we conclude that this change in 
its habitat is not likely to negatively impact the Kittlitz's murrelet 
at the population- or species-level because available data do not 
suggest that glaciers are an essential habitat feature to their life 
history. We concluded that this species has the ability to adapt or is 
resilient to changing environmental conditions, and therefore changes 
in glaciers should not directly threaten the viability of the 
Kittlitz's murrelet population.
    The Kittlitz's murrelet spends most of its life at sea and 
therefore is subject to ongoing and forecasted changes in ocean 
conditions that may affect its prey base, which in turn, would likely 
affect its survival and reproduction. We considered potential 
consequences to the Kittlitz's murrelet and its prey as a result of 
ocean warming and acidification and decadal-scale ocean variability, or 
climatic regime shifts. We relied on information about the species' 
diet and foraging preferences, as well as population trend, to assess 
potential impacts to this species from changes in ocean conditions (see 
Factor A discussion).
    We expect changes in ocean conditions within the range of the 
Kittlitz's murrelet to occur, but we cannot determine the demographic 
response of this species or its prey to these changes, largely owing to 
sparse information on diet and demographics of the Kittlitz's murrelet. 
Ocean warming and acidification is a global problem that will intensify 
with continued carbon dioxide emissions and may significantly affect 
marine ecosystems, especially those in high-latitude regions. As ocean 
temperatures change, we anticipate poleward shifts in distribution of 
marine species that have limited temperature ranges, changes to the 
thermohaline circulation, variability in the timing and magnitude of 
phytoplankton blooms, and changes in the local abundance of forage fish 
(see Factor A discussion for details). In addition, calcifying marine 
organisms, particularly pteropod snails, a common prey item for various 
zooplankton and fish, are expected to be most affected by increased 
ocean acidity and subsequent decreases in carbonate compounds. Although 
the frequency and intensity is unpredictable, we also assume that 
oceanic regime shifts will continue to occur in the North Pacific Ocean 
and Bering and Chukchi seas, as they have over the last century, 
causing subsequent community or taxonomic reorganizations. 
Consequently, as a top predator in the marine ecosystem, the

[[Page 61797]]

Kittlitz's murrelet may experience alterations to underlying food webs 
in the future. However, the Kittlitz's murrelet has a diverse diet, 
appears to have the ability to switch prey when necessary, and can 
forage successfully in a variety of marine and perhaps freshwater 
habitats (see Foraging, above). These are all characteristics that 
should facilitate adaptation and resiliency in diet and foraging 
preferences to changes in ocean conditions as a result of warming, 
acidification, and regime shifts. Nesting Kittlitz's murrelets will 
continue to require access to high-quality forage fish for delivery to 
chicks at nests, but we have little information to suggest that changes 
in ocean conditions in response to climate change are limiting or will 
limit nest success at the population or species level in the 
foreseeable future. Furthermore, we do not have evidence that the 
Kittlitz's murrelet or its diet have fluctuated concurrently with 
previous regime shifts or ocean warming and acidification. Thus, the 
best available information suggests that changes in ocean conditions do 
not currently put the species at risk of extinction, nor are they 
likely to do so in the foreseeable future.
    The Kittlitz's murrelet is considered to be vulnerable to marine 
oil pollution because it spends most of its annual cycle at sea, 
forages by diving and pursuing prey, and is typically found nearshore. 
We anticipate marine traffic within the range of the Kittlitz's 
murrelet to increase, but the rate of increase is dependent on economic 
activity and natural resource development. As marine traffic increases, 
the risk of petroleum contamination from both accidental spills and 
routine vessel operation is also expected to increase. We assessed the 
spatial and temporal overlap of marine oil spills and contaminated 
sites since 1995, and the seasonal distribution and abundance of the 
Kittlitz's murrelet in order to determine the magnitude of the risk to 
this species from marine pollution (see Factor A discussion). We found 
that overlap was generally low, with most spills releasing small 
amounts of substance in localized areas at times of the year when 
Kittlitz's murrelet densities were relatively low. Although few in 
number, larger spills did occur and overlap with the distribution of 
the Kittlitz's murrelet, primarily during the breeding season in Prince 
William Sound and near Adak Island. However, the broad distribution and 
relatively low densities of the Kittlitz's murrelet on the water 
throughout most of the year reduce the risk of population-level impacts 
from any single event, with the exception being the 1989 Exxon Valdez 
oil spill. In addition, technological and regulatory improvements, such 
as the Oil Pollution Act of 1990, are likely to reduce the risk of 
contamination and to improve response and cleanup in the event of a 
spill. We conclude that exposure to hydrocarbon contamination is an 
acute and chronic source of mortality of low numbers of individual 
Kittlitz's murrelets that does not rise to the level of a threat to the 
persistence of this species now, nor is it likely to do so in the 
future.
    Many life-history traits of the Kittlitz's murrelet developed to 
avoid predation at the nest, on the water, or in transit. We assessed 
predation of nestling and adult Kittlitz's murrelets by native, 
introduced, and transplanted predators to identify possible factors 
that may have resulted in changes to predation rates of the Kittlitz's 
murrelet. We first identified known predators and their distribution 
and diet across the range of the Kittlitz's murrelet, and then we 
evaluated local or population trend of those predators and possible 
factors contributing to the trend. We categorized predation events into 
two types: nest predation and active predation (see Factor C 
discussion).
    In some parts of this species' range, nest predation by fox appears 
to be a significant cause of nest failure, but we have no information 
to indicate that fox abundance or predation rates on Kittlitz's 
murrelet eggs or nestlings has increased or is likely to increase in 
the future. Fox and their prey were introduced to many islands of 
coastal Alaska and likely had an effect on local populations of 
Kittlitz's murrelets, but over the last few decades, eradication 
efforts have nearly eliminated all introduced fox, thereby removing the 
impact to Kittlitz's murrelets. In some areas, introduced species may 
have had and continue to have an indirect impact to the Kittlitz's 
murrelet by enhancing prey abundance for native species that are nest 
predators such as fox. Similarly, nest sites that are currently 
inaccessible by terrestrial predators, may be reachable as glaciers 
recede and primary succession follows. While we can postulate about 
possible changes in rates and patterns of nest predation of the 
Kittlitz's murrelet, we have no credible information to support the 
proposition that these changes actually occurred, are occurring, or 
have had a population- or species-level impact to the Kittlitz's 
murrelet.
    Active predation, when adults or juveniles are killed away from the 
nest site, is more difficult to quantify, but has potential to have a 
greater population-level impact than nest predation because it can 
result in adult mortality and likely occurs rangewide and year-round. 
Peregrine falcons and bald eagles are the only known active predators 
of the Kittlitz's murrelet, but the latter species likely kills far 
fewer individual murrelets compared to the peregrine falcon, which 
along the coast feeds primarily on small alcids. Populations of both of 
these raptor species have fluctuated over the last century due to 
human-caused influences (e.g., persecution, exposure to contaminants) 
and may be benefitting from glacial recession, although credible 
evidence is lacking. We found information to suggest that in at least 
one glacial fjord system, peregrine falcons can prey on Kittlitz's 
murrelets at rates that could have an impact to the local population, 
but any impact is likely to be localized and temporary until other 
alternate prey species colonize these newly created habitats. Thus, we 
found that predation, in and of itself, is not a population- or 
species-level threat to the Kittlitz's murrelet, nor is it likely to 
become a threat in the future.
    In summary, we found that the Kittlitz's murrelet experiences 
stressors in its marine and terrestrial habitats throughout its annual 
cycle and range, but based on our consideration of the best available 
scientific and commercial data information we determined that the 
identified stressors, individually or collectively, do not pose a 
threat to the species at the population- or range-wide level now or in 
the foreseeable future. Some local populations of the Kittlitz's 
murrelet likely declined, but there is no identified causal link 
between demographic change in this species and the stressors evaluated 
in our assessment. Furthermore, when analyzed collectively, we found 
that populations of Kittlitz's murrelet are currently stable or 
possibly slightly declining. We acknowledge that many of the stressors 
facing this species are occurring, and some will likely increase in the 
future, but we cannot predict the demographic response of the 
Kittlitz's murrelet to changes in these stressors. We identified some 
known sources of mortality to small numbers of Kittlitz's murrelet, but 
most were temporally episodic, spatially localized, or both. We 
postulated that some life-history traits and behaviors of the 
Kittlitz's murrelet, such as their broad distribution and variable 
diet, will counterbalance or mitigate possible effects of the 
identified stressors, including those associated with climate

[[Page 61798]]

change. Based on our review of the best available scientific and 
commercial information pertaining to the five factors, we find that the 
stressors are not of sufficient imminence, intensity, or magnitude to 
indicate that the Kittlitz's murrelet is in danger of extinction 
(endangered), or likely to become endangered within the foreseeable 
future (threatened), throughout all of its range.

Distinct Vertebrate Population Segment

    After assessing whether the species is endangered or threatened 
throughout its range, we next consider whether a distinct vertebrate 
population segment (DPS) of the Kittlitz's murrelet meets the 
definition of an endangered or threatened species.
    Under the Service's Policy Regarding the Recognition of Distinct 
Vertebrate Population Segments Under the Endangered Species Act (61 FR 
4722, February 7, 1996), three elements are considered in the decision 
concerning the establishment and classification of a possible DPS. 
These are applied similarly for addition to or removal from the Federal 
List of Endangered and Threatened Wildlife. These elements include:
    (1) The discreteness of a population in relation to the remainder 
of the species to which it belongs;
    (2) The significance of the population segment to the species to 
which it belongs; and
    (3) The population segment's conservation status in relation to the 
Act's standards for listing, delisting, or reclassification (i.e., is 
the population segment endangered or threatened).
Discreteness
    Under the DPS policy, a population segment of a vertebrate taxon 
may be considered discrete if it satisfies either one of the following 
conditions:
    (1) It is markedly separated from other populations of the same 
taxon as a consequence of physical, physiological, ecological, or 
behavioral factors. Quantitative measures of genetic or morphological 
discontinuity may provide evidence of this separation.
    (2) It is delimited by international governmental boundaries within 
which differences in control of exploitation, management of habitat, 
conservation status, or regulatory mechanisms exist that are 
significant in light of section 4(a)(1)(D) of the Act.
    The Kittlitz's murrelet is considered a single panmictic 
population, but recent studies suggest that there is strong population 
genetic structure in this species, resulting in at least two genetic 
groups. A comprehensive and targeted genetic study that adequately 
samples individual Kittlitz's murrelets from across their range, 
including Russia, at a specified time of year has not been completed. 
However, based on the most recent genetic analysis, there is an eastern 
group of the Kittlitz's murrelet, ranging from Glacier Bay to Kodiak 
Island in the Gulf of Alaska during the breeding season, and a western 
group that occupies Adak, Agattu, and Attu islands in the central and 
western Aleutian Archipelago during the breeding season (see Taxonomy 
and Species Description, above, for more details). There are low levels 
of contemporary movement among the two groups, suggesting that 
connectivity still exists with at least some individual Kittlitz's 
murrelets interbreeding and producing viable offspring. The area 
between Atka and Unalaska islands in the eastern Aleutians and in 
northern Alaska appear to be contact zones where Kittlitz's murrelets 
have mixed ancestry of both groups. We accept the genetic basis of the 
eastern and western groups of the Kittlitz's murrelet and therefore 
evaluated whether either group meets the definition of discreteness as 
described in the 1996 DPS policy.
    We assessed physical, physiological, ecological, and behavioral 
factors of Kittlitz's murrelets in the eastern and western groups to 
determine the level of separation between the two genetic groups. There 
are no known morphological or physical differences, such as egg 
characteristics, plumage coloration, size, wing or tail length, bill 
measurements, or molt patterns, between the eastern and western groups 
of the Kittlitz's murrelet. Similarly, we have no information to 
suggest that flight, swimming and diving, sexual behavior (mate 
attraction, pair bonding), vocalizations, degree of socialization, or 
interspecific behavior is different between the two groups. Breeding 
phenology is slightly later in the western group compared to the 
eastern group, but this difference is most certainly due to the 
persistence of sea ice and terrestrial ice and snow in the Aleutian 
Islands compared to the Gulf of Alaska; in fact, phenology is most 
delayed in northern Alaska, where mixed ancestry of the Kittlitz's 
murrelet occurs. Incubation length and post-hatching parental care are 
similar, but length of the chick-rearing period is greater at nests 
monitored in the Aleutian Islands compared to nests in the Gulf of 
Alaska. The difference in average number of days between hatching and 
fledging is presumably due to quality of chick diet (see Reproductive 
Performance and Factor A discussion), not an ecological or behavioral 
difference between Kittlitz's murrelets in the western and eastern 
groups. Post-breeding migration timing and routes of Kittlitz's 
murrelets in the eastern and western groups are similar with 
individuals moving into the Bering and Chukchi seas in August and 
September. Individual Kittlitz's murrelets have not been tracked 
between October and May, and, therefore, we cannot evaluate possible 
overwinter separation of Kittlitz's murrelets by group.
    The only possible ecological difference in Kittlitz's murrelets 
belonging to the eastern and western genetic groups is associated with 
nesting habitat. In the central and western Aleutian Islands, 
Kittlitz's murrelets nest in areas with greater amounts of vegetative 
cover (51 percent) compared to nests in the Gulf of Alaska (3-12 
percent) and northern Alaska (14 percent). However, regardless of the 
region, Kittlitz's murrelets consistently nest in the least vegetated 
areas available on the landscape, presumably to maximize camouflage and 
nest safety from predators (see Nesting for more details). Thus, we do 
not know whether or not the difference in percent vegetative cover near 
nest sites serves as ecological separation of Kittlitz's murrelets in 
the western and eastern groups. Although the distribution of the 
genetic groups may be partially explained by the distribution of 
glaciers, there are several regions of genetic introgression, including 
the eastern Aleutian Islands and northern Alaska, as well as areas in 
the eastern group, like Kodiak Island, that lack glaciers. Furthermore, 
as mentioned above, there are low levels of contemporary movement 
between these two genetic groups, suggesting that genetic continuity 
exists.
    The Kittlitz's murrelet is broadly distributed across coastal 
Alaska and eastern Russia where it spends its entire annual cycle, but 
only less than 5 percent of the minimum global population of the 
Kittlitz's murrelet resides in Russian waters during the breeding 
season. Despite the international governmental boundary essentially 
bisecting the distribution of this species, we have no reason to 
conclude that differences in control of exploitation, management of the 
habitat, conservation status of the species, or regulatory mechanisms 
exist that are significant to the listing status of the Kittlitz's 
murrelet.

[[Page 61799]]

Determination of Distinct Population Segment
    We determine, based on a review of the best available information, 
that the western and eastern populations of the Kittlitz's murrelet do 
not meet the discreteness conditions of the 1996 DPS policy. Therefore, 
neither of these population segments qualifies as a DPS under our 
policy and is not a listable entity under the Act.
    The DPS policy is clear that significance is analyzed only when a 
population segment has been identified as discrete. Since we found that 
the population segment did not meet the discreteness element, we will 
not conduct an evaluation of significance.

Significant Portion of the Range

    Under the Act and our implementing regulations, a species may 
warrant listing if it is endangered or threatened throughout all or a 
significant portion of its range. The Act defines ``endangered 
species'' as any species which is ``in danger of extinction throughout 
all or a significant portion of its range,'' and ``threatened species'' 
as any species which is ``likely to become an endangered species within 
the foreseeable future throughout all or a significant portion of its 
range.'' The definition of ``species'' is also relevant to this 
discussion. The Act defines ``species'' as follows: ``The term 
`species' includes any subspecies of fish or wildlife or plants, and 
any distinct population segment [DPS] of any species of vertebrate fish 
or wildlife which interbreeds when mature.'' The phrase ``significant 
portion of its range'' (SPR) is not defined by the statute, and we have 
never addressed in our regulations: (1) The consequences of a 
determination that a species is either endangered or likely to become 
so throughout a significant portion of its range, but not throughout 
all of its range; or (2) what qualifies a portion of a range as 
``significant.''
    Two recent district court decisions have addressed whether the SPR 
language allows the Service to list or protect less than all members of 
a defined ``species'': Defenders of Wildlife v. Salazar, 729 F. Supp. 
2d 1207 (D. Mont. 2010), concerning the Service's delisting of the 
Northern Rocky Mountain gray wolf (74 FR 15123, April 2, 2009); and 
WildEarth Guardians v. Salazar, 2010 U.S. Dist. LEXIS 105253 (D. Ariz. 
September 30, 2010), concerning the Service's 2008 finding on a 
petition to list the Gunnison's prairie dog (73 FR 6660, February 5, 
2008). The Service had asserted in both of these determinations that it 
had authority, in effect, to protect only some members of a 
``species,'' as defined by the Act (i.e., species, subspecies, or DPS), 
under the Act. Both courts ruled that the determinations were arbitrary 
and capricious on the grounds that this approach violated the plain and 
unambiguous language of the Act. The courts concluded that reading the 
SPR language to allow protecting only a portion of a species' range is 
inconsistent with the Act's definition of ``species.'' The courts 
concluded that once a determination is made that a species (i.e., 
species, subspecies, or DPS) meets the definition of ``endangered 
species'' or ``threatened species,'' it must be placed on the list in 
its entirety and the Act's protections applied consistently to all 
members of that species (subject to modification of protections through 
special rules under sections 4(d) and 10(j) of the Act).
    Consistent with that interpretation, and for the purposes of this 
finding, we interpret the phrase ``significant portion of its range'' 
in the Act's definitions of ``endangered species'' and ``threatened 
species'' to provide an independent basis for listing; thus there are 
two situations (or factual bases) under which a species would qualify 
for listing: a species may be endangered or threatened throughout all 
of its range; or a species may be endangered or threatened in only a 
significant portion of its range. If a species is in danger of 
extinction throughout a significant portion of its range, the species 
is an ``endangered species.'' The same analysis applies to ``threatened 
species.'' Based on this interpretation and supported by existing case 
law, the consequence of finding that a species is endangered or 
threatened in only a significant portion of its range is that the 
entire species shall be listed as endangered or threatened, 
respectively, and the Act's protections shall be applied across the 
species' entire range.
    We conclude, for the purposes of this finding, that interpreting 
the significant portion of its range phrase as providing an independent 
basis for listing is the best interpretation of the Act because it is 
consistent with the purposes and the plain meaning of the key 
definitions of the Act; it does not conflict with established past 
agency practice (i.e., prior to the 2007 Solicitor's Opinion), as no 
consistent, long-term agency practice has been established; and it is 
consistent with the judicial opinions that have most closely examined 
this issue. Having concluded that the phrase ``significant portion of 
its range'' provides an independent basis for listing and protecting 
the entire species, we next turn to the meaning of ``significant'' to 
determine the threshold for when such an independent basis for listing 
exists.
    Although there are potentially many ways to determine whether a 
portion of a species' range is ``significant,'' we conclude, for the 
purposes of this finding, that the significance of the portion of the 
range should be determined based on its biological contribution to the 
conservation of the species. For this reason, we describe the threshold 
for ``significant'' in terms of an increase in the risk of extinction 
for the species. We conclude that a biologically based definition of 
``significant'' best conforms to the purposes of the Act, is consistent 
with judicial interpretations, and best ensures species' conservation. 
Thus, for the purposes of this finding, and as explained further below, 
a portion of the range of a species is ``significant'' if its 
contribution to the viability of the species is so important that 
without that portion, the species would be in danger of extinction.
    We evaluate biological significance based on the principles of 
conservation biology using the concepts of redundancy, resiliency, and 
representation. Resiliency describes the characteristics of a species 
and its habitat that allow it to recover from periodic disturbance. 
Redundancy (having multiple populations distributed across the 
landscape) may be needed to provide a margin of safety for the species 
to withstand catastrophic events. Representation (the range of 
variation found in a species) ensures that the species' adaptive 
capabilities are conserved. Redundancy, resiliency, and representation 
are not independent of each other, and some characteristic of a species 
or area may contribute to all three. For example, distribution across a 
wide variety of habitat types is an indicator of representation, but it 
may also indicate a broad geographic distribution contributing to 
redundancy (decreasing the chance that any one event affects the entire 
species), and the likelihood that some habitat types are less 
susceptible to certain threats, contributing to resiliency (the ability 
of the species to recover from disturbance). None of these concepts is 
intended to be mutually exclusive, and a portion of a species' range 
may be determined to be ``significant'' due to its contributions under 
any one or more of these concepts.
    For the purposes of this finding, we determine if a portion's 
biological contribution is so important that the portion qualifies as 
``significant'' by asking whether without that portion, the 
representation, redundancy, or

[[Page 61800]]

resiliency of the species would be so impaired that the species would 
have an increased vulnerability to threats to the point that the 
overall species would be in danger of extinction (i.e., would be 
``endangered''). Conversely, we would not consider the portion of the 
range at issue to be ``significant'' if there is sufficient resiliency, 
redundancy, and representation elsewhere in the species' range that the 
species would not be in danger of extinction throughout its range if 
the population in that portion of the range in question became 
extirpated (extinct locally).
    We recognize that this definition of ``significant'' (a portion of 
the range of a species is ``significant'' if its contribution to the 
viability of the species is so important that without that portion, the 
species would be in danger of extinction) establishes a threshold that 
is relatively high. On the one hand, given that the consequences of 
finding a species to be endangered or threatened in an significant 
portion of its range would be listing the species throughout its entire 
range, it is important to use a threshold for ``significant'' that is 
robust. It would not be meaningful or appropriate to establish a very 
low threshold whereby a portion of the range can be considered 
``significant'' even if only a negligible increase in extinction risk 
would result from its loss. Because nearly any portion of a species' 
range can be said to contribute some increment to a species' viability, 
use of such a low threshold would require us to impose restrictions and 
expend conservation resources disproportionately to conservation 
benefit: listing would be rangewide, even if only a portion of the 
range of minor conservation importance to the species is imperiled. On 
the other hand, it would be inappropriate to establish a threshold for 
``significant'' that is too high. This would be the case if the 
standard were, for example, that a portion of the range can be 
considered ``significant'' only if threats in that portion result in 
the entire species' being currently endangered or threatened. Such a 
high bar would not give the significant portion of its range phrase 
independent meaning, as the Ninth Circuit held in Defenders of Wildlife 
v. Norton, 258 F.3d 1136 (9th Cir. 2001).
    The definition of ``significant'' used in this finding carefully 
balances these concerns. By setting a relatively high threshold, we 
minimize the degree to which restrictions will be imposed or resources 
expended that do not contribute substantially to species conservation. 
But we have not set the threshold so high that the phrase ``in a 
significant portion of its range'' loses independent meaning. 
Specifically, we have not set the threshold as high as it was under the 
interpretation presented by the Service in the Defenders litigation. 
Under that interpretation, the portion of the range would have to be so 
important that current imperilment there would mean that the species 
would be currently imperiled everywhere. Under the definition of 
``significant'' used in this finding, the portion of the range need not 
rise to such an exceptionally high level of biological significance. 
(We recognize that if the species is imperiled in a portion that rises 
to that level of biological significance, then we should conclude that 
the species is in fact imperiled throughout all of its range, and that 
we would not need to rely on the significant portion of its range 
language for such a listing.) Rather, under this interpretation we ask 
whether the species would be endangered everywhere without that 
portion, i.e., if that portion were completely extirpated. In other 
words, the portion of the range need not be so important that even the 
species being in danger of extinction in that portion would be 
sufficient to cause the species in the remainder of the range to be 
endangered; rather, the complete extirpation (in a hypothetical future) 
of the species in that portion would be required to cause the species 
in the remainder of the range to be endangered.
    The range of a species can theoretically be divided into portions 
in an infinite number of ways. However, there is no purpose to 
analyzing portions of the range that have no reasonable potential to be 
significant or to analyzing portions of the range in which there is no 
reasonable potential for the species to be endangered or threatened. To 
identify only those portions that warrant further consideration, we 
determine whether there is substantial information indicating that: (1) 
The portions may be ``significant,'' and (2) the species may be in 
danger of extinction there or likely to become so within the 
foreseeable future. Depending on the biology of the species, its range, 
and the threats it faces, it might be more efficient for us to address 
the significance question first or the status question first. Thus, if 
we determine that a portion of the range is not ``significant,'' we do 
not need to determine whether the species is endangered or threatened 
there; if we determine that the species is not endangered or threatened 
in a portion of its range, we do not need to determine if that portion 
is ``significant.'' In practice, a key part of the determination that a 
species is in danger of extinction in a significant portion of its 
range is whether the threats are geographically concentrated in some 
way. If the threats to the species are essentially uniform throughout 
its range, no portion is likely to warrant further consideration. 
Moreover, if any concentration of threats to the species occurs only in 
portions of the species' range that clearly would not meet the 
biologically based definition of ``significant,'' such portions will 
not warrant further consideration.
    We evaluated the current range of the Kittlitz's murrelet to 
determine if there is any apparent geographic concentration of 
potential threats to this species. We examined potential threats from 
climate change, exposure to environmental contaminants and marine 
pollution, disease, changes in predation, disturbance from vessel 
traffic, and incidental take in fisheries. We found no concentration of 
threats that suggest the Kittlitz's murrelet may be in danger of 
extinction in a portion of its range. We found no portion of its range 
where threats are significantly concentrated or substantially greater 
than in other portions of its range. Therefore, we find that known 
factors affecting the Kittlitz's murrelet are essentially uniform 
throughout its range, indicating no portion of the range of the 
Kittlitz's murrelet warrants further consideration of possible 
endangered or threatened status under the Act. The best available 
information does not suggest that there has been a noteable range 
contraction of the Kittlitz's murrelet, and therefore we find that lost 
historical range does not constitute an important component of our 
analysis of whether any particular area is a significant portion of the 
range for the Kittlitz's murrelet.

Conclusion of 12-Month Finding

    Our review of the best available scientific and commercial 
information indicates that the Kittlitz's murrelet is not in danger of 
extinction (endangered) nor likely to become endangered within the 
foreseeable future (threatened), throughout all or a significant 
portion of its range. Therefore, we find that listing the Kittlitz's 
murrelet as an endangered or threatened species under the Act is not 
warranted at this time.
    We request that you submit any new information concerning the 
status of, or threats to, the Kittlitz's murrelet to our Juneau Fish 
and Wildlife Field Office (see ADDRESSES) whenever it becomes 
available. New information will help us monitor the Kittlitz's murrelet 
and

[[Page 61801]]

encourage its conservation. If an emergency situation develops for the 
Kittlitz's murrelet, we will act to provide immediate protection.

References Cited

    A complete list of references cited is available on the Internet at 
http://www.regulations.gov at Docket No. FWS-R7-ES-2013-0099 and upon 
request from the Juneau Fish and Wildlife Field Office (see ADDRESSES).

Authors

    The primary authors of this notice are the staff members of the 
Juneau Fish and Wildlife Field 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: September 23, 2013.
Rowan W. Gould,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2013-24172 Filed 10-2-13; 8:45 am]
BILLING CODE 4310-55-P