[Federal Register Volume 81, Number 3 (Wednesday, January 6, 2016)]
[Proposed Rules]
[Pages 435-458]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-32473]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R7-ES-2015-0167; FF07C00000 FXES11190700000 167F1611MD]
Endangered and Threatened Wildlife and Plants; 12-Month Finding
on a Petition To List the Alexander Archipelago Wolf 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 Alexander Archipelago wolf
(Canis lupus ligoni) as an endangered or threatened species and to
designate critical habitat under the Endangered Species Act of 1973, as
amended (Act). The petitioners provided three listing options for
consideration by the Service: Listing the Alexander Archipelago wolf
throughout its range; listing Prince of Wales Island (POW) as a
significant portion of its range; or listing the population on Prince
of Wales Island as a distinct population segment (DPS). After review of
the best available scientific and commercial information, we find that
listing the Alexander Archipelago wolf is not warranted at this time
throughout all or a significant portion of its range, including POW. We
also find that the Alexander Archipelago wolf population on POW does
not not meet the criteria of the Service's DPS policy, and, therefore,
it does not constitute a listable entity under the Act. We ask the
public to submit to us any new information that becomes available
concerning the threats to the Alexander Archipelago wolf or its habitat
at any time.
DATES: The finding announced in this document was made on January 6,
2016.
ADDRESSES: This finding is available on the Internet at http://www.regulations.gov at Docket No. FWS-R7-ES-2015-0167. Supporting
documentation we used in preparing this finding will be available for
public inspection, by appointment, during normal business hours at the
U.S. Fish and Wildlife Service, Anchorage Fish and Wildlife Field
Office, 4700 BLM Rd., Anchorage, AK 99507-2546. Please submit any new
information, materials, comments, or questions concerning this finding
to the above street address.
FOR FURTHER INFORMATION CONTACT: Soch Lor, Field Supervisor, Anchorage
Fish and Wildlife Field Office (see ADDRESSES); by telephone at 907-
271-2787; or by facsimile at 907-271-2786. 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.
This finding is based upon the ``Status Assessment for the
Alexander Archipelago Wolf (Canis lupus ligoni)'' (Service 2015,
entire) (hereafter, Status Assessment) and the scientific analyses of
available information prepared by Service biologists from the Anchorage
Fish and Wildlife Field Office, the Alaska Regional Office, and the
Headquarters Office. The Status Assessment contains the best scientific
and commercial data available concerning the status of the Alexander
Archipelago wolf, including the past, present, and future stressors. As
such, the Status Assessment provides the scientific basis that informs
our regulatory decision in this document, which involves the further
application
[[Page 436]]
of standards within the Act and its implementing regulations and
policies.
Previous Federal Actions
On December 17, 1993, the Service received a petition, from the
Biodiversity Legal Foundation, Eric Holle, and Martin Berghoffen, to
list the Alexander Archipelago wolf as an endangered or threatened
species under the Act. On May 20, 1994, we announced a 90-day finding
that the petition presented substantial information indicating that the
requested action may be warranted, and we initiated a status review of
the Alexander Archipelago wolf and opened a public comment period until
July 19, 1994 (59 FR 26476). On August 26, 1994, we reopened the
comment period on the status review to accept comments until October 1,
1994 (59 FR 44122). The Service issued its 12-month finding that
listing the Alexander Archipelago wolf was not warranted on February
23, 1995 (60 FR 10056).
On February 7, 1996, the Southwest Center for Biological Diversity,
Biodiversity Legal Foundation, Save the West, Save America's Forests,
Native Forest Network, Native Forest Council, Eric Holle, Martin
Berghoffen, and Don Muller filed suit in the U.S. Court for the
District of Columbia challenging the Service's not-warranted finding.
On October 9, 1996, the U.S. District Court remanded the 12-month
finding to the Secretary of the Interior, instructing him to reconsider
the determination ``on the basis of the current forest plan, and status
of the wolf and its habitat, as they stand today'' (96 CV 00227 DDC).
The Court later agreed to the Service's proposal to issue a new finding
on June 1, 1997. On December 5, 1996, we published a document
announcing the continuation of the status review for the Alexander
Archipelago wolf and opening a public comment period until January 21,
1997 (61 FR 64496). The comment period was then extended or reopened
through three subsequent publications (61 FR 69065, December 31, 1996;
62 FR 6930, February 14, 1997; 62 FR 14662, March 27, 1997), until it
closed on April 4, 1997.
Prior to the publication of a 12-month finding, however, the U.S.
Forest Service (USFS) issued the 1997 Tongass Land and Resource
Management Plan Revision, which superseded the 1979 version of the
plan. In keeping with the U.S. District Court's order that a finding be
based upon the ``current forest plan,'' the District Court granted us
an extension until August 31, 1997, to issue our 12-month finding so
that the petitioners, the public, and the Service could reconsider the
status of the Alexander Archipelago wolf under the revised Tongass Land
and Resource Management Plan. Therefore, the Service reopened the
public comment period on the status review of the Alexander Archipelago
wolf from June 12, 1997, to July 28, 1997 (62 FR 32070, June 12, 1997),
and we then reevaluated all of the best available information on the
Alexander Archipelago wolf, as well as long-term habitat projections
for the Tongass National Forest included in the 1997 Tongass Land and
Resource Management Plan Revision. On September 4, 1997, we published a
12-month finding that listing the Alexander Archipelago wolf was not
warranted (62 FR 46709).
On August 10, 2011, we received a petition dated August 10, 2011,
from the Center for Biological Diversity and Greenpeace, requesting
that the Alexander Archipelago wolf be listed as an endangered or
threatened species under the Act and critical habitat be designated.
Included in the petition was supporting information regarding the
subspecies' taxonomy and ecology, distribution, abundance and
population trends, causes of mortality, and conservation status. The
petitioners also requested that we consider: (1) Prince of Wales Island
(POW) as a significant portion of the range of the Alexander
Archipelago wolf; and (2) wolves on POW and nearby islands as a
distinct population segment. We note here that a significant portion of
the range is not a listable entity in and of itself, but instead
provides an independent basis for listing and is part of our analysis
to determine whether or not listing as an endangered or threatened
species is warranted. We published the 90-day finding for the Alexander
Archipelago wolf on March 31, 2014, stating that the petition presented
substantial information indicating that listing may be warranted (79 FR
17993).
On June 20, 2014, the Center for Biological Diversity, Greenpeace,
Inc., and The Boat Company (collectively, plaintiffs) filed a complaint
against the Service for failure to complete a 12-month finding for the
Alexander Archipelago wolf within the statutory timeframe. On September
22, 2014, the Service and the aforementioned plaintiffs entered into a
stipulated settlement agreement stating that the Service shall review
the status of the Alexander Archipelago wolf and submit to the Federal
Register a 12-month finding as to whether listing as endangered or
threatened is warranted, not warranted, or warranted but precluded by
other pending proposals, on or before December 31, 2015. In Fiscal Year
2015, the Service initiated work on a 12-month finding for the
Alexander Archipelago wolf.
On September 14, 2015, the Service received a petition to list on
an emergency basis the Alexander Archipelago wolf as an endangered or
threatened species under the Act. The petition for emergency listing
was submitted by Alaska Wildlife Alliance, Cascadia Wildlands, Center
for Biological Diversity, Greater Southeast Alaska Conservation
Community, Greenpeace, and The Boat Company. The petitioners stated
that harvest of the Alexander Archipelago wolf in Game Management Unit
(GMU) 2, in light of an observed recent population decline, would put
the population in danger of extinction. On September 28, 2015, the
Service acknowledged receipt of the petition for emergency listing to
each of the petitioners. In those letters, we indicated that we would
continue to evaluate the status of the Alexander Archipelago wolf as
part of the settlement agreement and that if at any point we determined
that emergency listing was warranted, an emergency rule may be promptly
developed.
This document constitutes the 12-month finding on the August 10,
2011, petition to list the Alexander Archipelago wolf as an endangered
or threatened species. For additional information and a detailed
discussion of the taxonomy, physical description, distribution,
demography, and habitat of the Alexander Archipelago wolf, please see
the Status Assessment for Alexander Archipelago Wolf (Canis lupus
ligoni) (Service 2015, entire) available under Docket No. FWS-R7-ES-
2015-0167 at http://www.regulations.gov, or from the Anchorage Fish and
Wildlife Field Office (see ADDRESSES).
Current Taxonomy Description
Goldman (1937, pp. 39-40) was the first to propose the Alexander
Archipelago wolf as a subspecies of the gray wolf. He described C. l.
ligoni as a dark colored subspecies of medium size and short pelage
(fur) that occupied the Alexander Archipelago and adjacent mainland of
southeastern Alaska. Additional morphometric analyses supported the
hypothesis that wolves in southeastern Alaska were phenotypically
distinct from other gray wolves in Alaska (Pedersen 1982, pp. 345,
360), although results also indicated similarities with wolves that
historically occupied coastal British Columbia, Vancouver Island, and
perhaps the contiguous western United States (Nowak 1983, pp. 14-15;
Friis 1985, p. 82). Collectively, these findings demonstrated that
wolves in southeastern Alaska had a closer affinity
[[Page 437]]
to wolves to the south compared to wolves to the north, suggesting that
either C. l. ligoni was not confined to southeastern Alaska and its
southern boundary should be extended southward (Friis 1985, p. 78) or
that C. l. ligoni should be combined with C. l. nubilus, the subspecies
that historically occupied the central and western United States (Nowak
1995, p. 396). We discuss these morphological studies and others in
detail in the Status Assessment (Service 2015, ``Morphological
analyses'').
More recently, several molecular ecology studies have been
conducted on wolves in southeastern Alaska and coastal British
Columbia, advancing our knowledge of wolf taxonomy beyond morphometric
analyses. Generally, results of these genetic studies were similar,
suggesting that coastal wolves in southeastern Alaska and coastal
British Columbia are part of the same genetic lineage (Breed 2007, pp.
5, 27, 30; Weckworth et al. 2011, pp. 2, 5) and that they appear to be
genetically differentiated from interior continental wolves (Weckworth
et al. 2005, p. 924; Munoz-Fuentes et al. 2009, p. 9; Weckworth et al.
2010, p. 368; Cronin et al. 2015, pp. 1, 4-6). However, interpretation
of the results differed with regard to subspecific designations; some
authors concluded that the level of genetic differentiation between
coastal and interior continental wolves constitutes a distinct coastal
subspecies, C. l. ligoni (Weckworth et al. 2005, pp. 924, 927; Munoz-
Fuentes et al. 2009, p. 12; Weckworth et al. 2010, p. 372; Weckworth et
al. 2011, p. 6), while other authors asserted that it does not
necessitate subspecies status (Cronin et al. 2015, p. 9). Therefore,
the subspecific identity, if any, of wolves in southeastern Alaska and
coastal British Columbia remained unresolved. As a cautionary note, the
inference of these genetic studies depends on the type of genetic
marker used and the spatial and temporal extent of the samples
analyzed; we review these studies and their key findings as they relate
to wolf taxonomy in detail in the Status Assessment (Service 2015,
``Genetic analyses'').
In the most recent meta-analysis of wolf taxonomy in North America,
Chambers et al. (2012, pp. 40-42) found evidence for differentiating
between coastal and inland wolves, although ultimately the authors
grouped wolves in southeastern Alaska and coastal British Columbia with
wolf populations that historically occupied the central and western
United States (C. l. nubilus). One of their primary reasons for doing
so was because coastal wolves harbored genetic material that also was
found only in historical samples of C. l. nubilus (Chambers et al.
2012, p. 41), suggesting that prior to extirpation of wolves by humans
in the western United States, C. l. nubilus extended northward into
coastal British Columbia and southeastern Alaska. However, this study
was conducted at a broad spatial scale with a focus on evaluating
taxonomy of wolves in the eastern and northeastern United States and
therefore was not aimed specifically at addressing the taxonomic status
of coastal wolves in western North America. Further, Chambers et al.
(2012, p. 41) recognized that understanding the phylogenetic
relationship of coastal wolves to other wolf populations assigned as C.
l. nubilus is greatly impeded by the extirpation of wolves (and the
lack of historical specimens) in the western United States. Lastly,
Chambers et al. (2012, p. 2) explicitly noted that their views on
subspecific designations were not intended as recommendations for
management units or objects of management actions, nor should they be
preferred to alternative legal classifications for protection, such as
those made under the Act. Instead, the authors stated that the
suitability of a subspecies as a unit for legal purposes requires
further, separate analysis weighing legal and policy considerations.
We acknowledge that the taxonomic status of wolves in southeastern
Alaska and coastal British Columbia is unresolved and that our
knowledge of wolf taxonomy in general is evolving as more sophisticated
and powerful tools become available (Service 2015, ``Uncertainty in
taxonomic status''). Nonetheless, based on our review of the best
available information, we found persuasive evidence suggesting that
wolves in southeastern Alaska and coastal British Columbia currently
form an ecological and genetic unit worthy of analysis under the Act.
Although zones of intergradation exist, contemporary gene flow between
coastal and interior continental wolves appears to be low (e.g.,
Weckworth et al. 2005, p. 923; Cronin et al. 2015, p. 8), likely due to
physical barriers, but perhaps also related to ecological differences
(Munoz-Fuentes et al. 2009, p. 6); moreover, coastal wolves currently
represent a distinct portion of genetic diversity for all wolves in
North America (Weckworth et al. 2010, p. 363; Weckworth et al. 2011,
pp. 5-6). Thus, we conclude that at most, wolves in southeastern Alaska
and coastal British Columbia are a distinct subspecies, C. l. ligoni,
of gray wolf, and at least, are a remnant population of C. l. nubilus.
For the purpose of this 12-month finding, we assume that the Alexander
Archipelago wolf (C. l. ligoni) is a valid subspecies of gray wolf that
occupies southeastern Alaska and coastal British Columbia and,
therefore, is a listable entity under the Act.
Species Information
Physical Description
The Alexander Archipelago wolf has been described as being darker
and smaller, with coarser and shorter hair, compared to interior
continental gray wolves (Goldman 1937, pp. 39-40; Wood 1990, p. 1),
although a comprehensive study or examination has not been completed.
Like most gray wolves, fur coloration of Alexander Archipelago wolves
varies considerably from pure white to uniform black, with most wolves
having a brindled mix of gray or tan with brown, black, or white. Based
on harvest records and wolf sightings, the black color phase appears to
be more common on the mainland of southeastern Alaska and coastal
British Columbia (20-30 percent) (Alaska Department of Fish and Game
[ADFG] 2012, pp. 5, 18, 24; Darimont and Paquet 2000, p. 17) compared
to the southern islands of the Alexander Archipelago (2 percent) (ADFG
2012, p. 34), and some of the gray-colored wolves have a brownish-red
tinge (Darimont and Paquet 2000, p. 17). The variation in color phase
of Alexander Archipelago wolves is consistent with the level of
variation observed in other gray wolf populations (e.g., Central Brooks
Range, Alaska) (Adams et al. 2008, p. 170).
Alexander Archipelago wolves older than 6 months weigh between 49
and 115 pounds (22 and 52 kilograms), with males averaging 83 pounds
(38 kilograms) and females averaging 69 pounds (31 kilograms) (British
Columbia Ministry of Forests, Lands and Natural Resource Operations
[BCMO] 2014, p. 3; Valkenburg 2015, p. 1). On some islands in the
archipelago (e.g., POW) wolves are smaller on average compared to those
on the mainland, although these differences are not statistically
significant (Valkenburg 2015, p. 1) (also see Service 2015, ``Physical
description''). The range and mean weights of Alexander Archipelago
wolves are comparable to those of other populations of gray wolves that
feed primarily on deer (Odocoileus spp.; e.g., northwestern Minnesota)
(Mech and Paul 2008, p. 935), but are lower than those of adjacent gray
wolf populations that regularly feed on larger ungulates
[[Page 438]]
such as moose (Alces americanus) (e.g., Adams et al. 2008, p. 8).
Distribution and Range
The Alexander Archipelago wolf currently occurs along the mainland
of southeastern Alaska and coastal British Columbia and on several
island complexes, which comprise more than 22,000 islands of varying
size, west of the Coast Mountain Range. Wolves are found on all of the
larger islands except Admiralty, Baranof, and Chichagof islands and all
of the Haida Gwaii, or Queen Charlotte Islands (see Figure 1, below)
(Person et al. 1996, p. 1; BCMO 2014, p. 14). The range of the
Alexander Archipelago wolf is approximately 84,595 square miles (mi\2\)
(219,100 square kilometers [km\2\]), stretching roughly 932 mi (1,500
km) in length and 155 mi (250 km) in width, although the northern,
eastern, and southern boundaries are porous and are not defined
sharply.
The majority (67 percent) of the range of the Alexander Archipelago
wolf falls within coastal British Columbia, where wolves occupy all or
portions of four management ``regions.'' These include Region 1
(entire), Region 2 (83 percent of entire region), Region 5 (22 percent
of entire region), and Region 6 (17 percent of entire region) (see
Figure 1, below). Thirty-three percent of the range of the Alexander
Archipelago wolf lies within southeastern Alaska where it occurs in all
of GMUs 1, 2, 3, and 5, but not GMU 4. See the Status Assessment
(Service 2015, ``Geographic scope'') for a more detailed explanation on
delineation of the range.
The historical range of the Alexander Archipelago wolf, since the
late Pleistocene period when the last glacial ice sheets retreated, was
similar to the current range with one minor exception. Between 1950 and
1970, wolves on Vancouver Island likely were extirpated by humans
(Munoz-Fuentes et al. 2010, pp. 547-548; Chambers et al. 2012, p. 41);
recolonization of the island by wolves from mainland British Columbia
occurred naturally and wolves currently occupy Vancouver Island.
In southeastern Alaska and coastal British Columbia, the landscape
is dominated by coniferous temperate rainforests, interspersed with
other habitat types such as sphagnum bogs, sedge-dominated fens, alpine
areas, and numerous lakes, rivers, and estuaries. The topography is
rugged with numerous deep, glacially-carved fjords and several major
river systems, some of which penetrate the Coast Mountain Range,
connecting southeastern Alaska and coastal British Columbia with
interior British Columbia and Yukon Territory. These corridors serve as
intergradation zones of variable width with interior continental
wolves; outside of them, glaciers and ice fields dominate the higher
elevations, separating the coastal forests from the adjacent inland
forest in continental Canada.
Within the range of the Alexander Archipelago wolf, land
stewardship largely lies with State, provincial, and Federal
governments. In southeastern Alaska, the majority (76 percent) of the
land is located within the Tongass National Forest and is managed by
the USFS. The National Park Service manages 12 percent of the land,
most of which is within Glacier Bay National Park. The remainder of the
land in southeastern Alaska is managed or owned by the State of Alaska
(4 percent), Native Corporations (3 percent), and other types of
ownership (e.g., private, municipal, tribal reservation; 5 percent). In
British Columbia (entire), most (94 percent) of the land and forest are
owned by the Province of British Columbia (i.e., Crown lands), 4
percent is privately owned, 1 percent is owned by the federal
government, and the remaining 1 percent is owned by First Nations and
others (British Columbia Ministry of Forests, Mines, and Lands 2010, p.
121).
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Life History
In this section, we briefly describe vital rates and population
dynamics, including population connectivity, of the Alexander
Archipelago wolf. For this 12-month finding, we considered a population
to be a collection of individuals of a species in a defined area; the
individuals in a population may or may not breed with other groups of
that species in other places (Mills 2013, p. 3). We delineated wolves
into populations based on GMUs in southeastern Alaska and Regions in
British Columbia (coastal portions only) because these are defined
areas and wolf populations are managed at these spatial
[[Page 440]]
scales (see Figure 1). For example, GMU 2 comprises one population of
wolves on POW and adjacent islands.
Abundance and Trend
Using the most recent and best available information, we estimate a
current, rangewide population of 850-2,700 Alexander Archipelago
wolves. The majority (roughly 62 percent) occurs in coastal British
Columbia with approximately 200-650 wolves in the southern portion
(Regions 1 and 2; about 24 percent of rangewide population) and 300-
1,050 wolves in the northern portion (Regions 5 and 6; about 38 percent
of rangewide population) (see Figure 1). In southeastern Alaska, we
estimate that currently the mainland (GMUs 1 and 5A) contains 150-450
wolves (about 18 percent of rangewide population), the islands in the
middle portion of the area (GMU 3) contain 150-350 wolves (about 14
percent of rangewide population), and the southwestern set of islands
(GMU 2) has 50-159 wolves (95 percent confidence intervals [CI], mean =
89 wolves; about 6 percent of rangewide population) (Person et al.
1996, p. 13; ADFG 2015a, p. 2). Our estimates are based on a variety of
direct and indirect methods with the only empirical estimate available
for GMU 2, which comprises POW and surrounding islands. See the Status
Assessment (Service 2015, ``Abundance and density'') for details on
derivation, assumptions, and caveats.
Similar to abundance, direct estimates of population trend of the
Alexander Archipelago wolf are available only for GMU 2 in southeastern
Alaska. In this GMU, fall population size has been estimated on four
occasions (1994, 2003, 2013, and 2014). Between 1994 and 2014, the
population was reduced from 356 wolves (95 percent CI = 148-564)
(Person et al. 1996, pp. 11-12; ADFG 2014, pp. 2-4) to 89 wolves (95
percent CI = 50-159) (ADFG 2015a, pp. 1-2), equating to an apparent
decline of 75 percent (standard error [SE] = 15), or 6.7 percent (SE =
2.8) annually. Although the numerical change in population size over
the 20-year period is notable, the confidence intervals of the
individual point estimates overlap. The most severe reduction occurred
over a single year (2013-2014), when the population dropped by 60
percent and the proportion of females in the sample was reduced from
0.57 (SE = 0.13) to 0.25 (SE = 0.11) (ADFG 2015a, p. 2). In the
remainder of southeastern Alaska, the trend of wolf populations is not
known.
In British Columbia, regional estimates of wolf population
abundance are generated regularly using indices of ungulate biomass,
and, based on these data, the provincial wolf population as a whole has
been stable or slightly increasing since 2000 (Kuzyk and Hatter 2014,
p. 881). In Regions 1, 2, 5, and 6, where the Alexander Archipelago
wolf occurs in all or a portion of each of these regions (see
Distribution and Range, above), the same trend has been observed (BCMO
2015a, p. 1). Because estimates of population trend are not specific to
the coastal portions of these regions only, we make the necessary
scientific assumption that the trend reported for the entire region is
reflective of the trend in the coastal portion of the region. This
assumption applies only to Regions 5 and 6, where small portions (22
and 17 percent, respectively) of the region fall within the range of
the Alexander Archipelago wolf; all of Region 1 and nearly all (83
percent) of Region 2 are within the range of the coastal wolf (see
Figure 1). Thus, based on the best available information, we found that
the wolf populations in coastal British Columbia have been stable or
slightly increasing over the last 15 years. See the Status Assessment
(Service 2015, ``Abundance and density'') for a more thorough
description of data assumptions and caveats.
Reproduction and Survival
Similar to the gray wolf, sizes of litters of the Alexander
Archipelago wolf can vary substantially (1-8 pups, mean = 4.1) with
inexperienced breeding females producing fewer pups than older, more
experienced mothers (Person and Russell 2009, p. 216). Although
uncommon, some packs fail to exhibit denning behavior or produce
litters in a given year, and no pack has been observed with multiple
litters (Person and Russell 2009, p. 216). Age of first breeding of the
Alexander Archipelago wolf is about 22 to 34 months (Person et al.
1996, p. 8).
We found only one study that estimated survival rates of Alexander
Archipelago wolves. Based on radio-collared wolves in GMU 2 between
1994 and 2004, Person and Russell (2008, p. 1545) reported mean annual
survival rate of wolves greater than 4 months old as 0.54 (SE = 0.17);
survival did not differ between age classes or sexes, but was higher
for resident wolves (0.65, SE = 0.17) compared to nonresidents (i.e.,
wolves not associated with a pack; 0.34, SE = 0.17). Average annual
rates of mortality attributed to legal harvest, unreported harvest, and
natural mortality were 0.23 (SE = 0.12), 0.19 (SE = 0.11), and 0.04 (SE
= 0.05), respectively, and these rates were correlated positively with
roads and other landscape features that created openings in the forest
(Person and Russell 2008, pp. 1545-1546).
In 2012, another study was initiated (and is ongoing) in GMU 2 that
involves collaring wolves, but too few animals have been collared so
far to estimate annual survival reliably (n = 12 wolves between 2012
and May 2015). Nonetheless, of those 12 animals, 5 died from legal
harvest, 3 from unreported harvest, and 1 from natural causes;
additionally, the fate of 2 wolves is unknown and 1 wolf is alive still
(ADFG 2015b, p. 4). Thus, overall, harvest of Alexander Archipelago
wolves by humans has accounted for most of the mortality of collared
wolves in GMU 2. Our review of the best available information did not
reveal any estimates of annual survival or mortality of wolves on other
islands or the mainland of southeastern Alaska and coastal British
Columbia.
Dispersal and Connectivity
Similar to gray wolves, Alexander Archipelago wolves either remain
in their natal pack or disperse (Person et al. 1996, p. 10), here
defined as permanent movement of an individual away from its pack of
origin. Dispersers typically search for a new pack to join or associate
with other wolves and ultimately form a new pack in vacant territories
or in vacant areas adjacent to established territories. Dispersal can
occur within or across populations; when it occurs across populations,
then population connectivity is achieved. Both dispersal and
connectivity contribute significantly to the health of individual
populations as well as the taxon as a whole.
Dispersal rates of the Alexander Archipelago wolf are available
only for GMU 2, where the annual rate of dispersal of radio-collared
wolves was 39 percent (95 percent CI = 23 percent, n = 18) with adults
greater than 2 years of age composing 79 percent of all dispersers
(Person and Ingle 1995, p. 20). Minimum dispersal distances from the
point of capture and radio-collaring ranged between 8 and 113 mi (13
and 182 km); all dispersing wolves remained in GMU 2 (Person and Ingle
1995, p. 23). Successful dispersal of individuals tends to be short in
duration and distance in part because survival of dispersing wolves is
low (annual survival rate = 0.16) (e.g., Peterson et al. 1984, p. 29;
Person and Russell 2008, p. 1547).
Owing to the rugged terrain and island geography across most of
southeastern Alaska and coastal British Columbia, population
connectivity probably is more limited for the
[[Page 441]]
Alexander Archipelago wolf compared to the gray wolf that inhabits
interior continental North America. Of the 67 Alexander Archipelago
wolves radio-collared in GMU 2, none emigrated to a different GMU
(Person and Ingle 1995, p. 23; ADFG 2015c, p. 2); similarly, none of
the four wolves collared in northern southeastern Alaska (GMU 1C and
1D) attempted long-distance dispersal, although the home ranges of
these wolves were comparatively large (ADFG 2015c, p. 2). Yet, of the
three wolves opportunistically radio-collared on Kupreanof Island (GMU
3), one dispersed to Revillagigedo Island (GMU 1A) (USFS 2015, p. 1),
an event that required at least four water crossings with the shortest
being about 1.2 mi (2.0 km) in length (see Figure 1). Thus, based on
movements of radio-collared wolves, demographic connectivity appears to
be more restricted for some populations than others; however, few data
exist outside of GMU 2, where the lack of emigration is well documented
but little is known about the rate of immigration.
Likewise, we found evidence suggesting that varying degrees of
genetic connectivity exist across populations of the Alexander
Archipelago wolf, indicating that some populations are more insular
than others. Generally, of the populations sampled, gene flow was most
restricted to and from the GMU 2 wolf population (Weckworth et al.
2005, p. 923; Breed 2007, p. 19; Cronin et al. 2015, Supplemental Table
3), although this population does not appear to be completely isolated.
Breed (2007, pp. 22-23) classified most wolves in northern coastal
British Columbia (Regions 5 and 6) as residents and more than half of
the wolves in the southern portion of southeastern Alaska (GMUs 1A and
2) as migrants of mixed ancestry. Further, the frequency of private
alleles (based on nuclear DNA) in the GMU 2 wolf population is low
relative to other Alexander Archipelago wolves (Weckworth et al. 2005,
p. 921; Breed 2007, p. 18), and the population does not harbor unique
haplotypes (based on mitochondrial DNA), both of which suggest that
complete isolation has not occurred. Thus, although some genetic
discontinuities of Alexander Archipelago wolves is evident, likely due
to geographical disruptions to dispersal and gene flow, genetic
connectivity among populations seems to be intact, albeit at low levels
for some populations (e.g., GMU 2). The scope of inference of these
genetic studies depends on the type of genetic marker used and the
spatial and temporal extent of the samples analyzed; we review key
aspects of these studies in more detail in the Status Assessment
(Service 2015, ``Genetic analyses,'' ``Genetic connectivity'').
Collectively, the best available information suggests that
demographic and genetic connectivity among Alexander Archipelago wolf
populations exists, but at low levels for some populations such as that
of GMU 2, likely due to geographical disruptions to dispersal and gene
flow. Based on the range of samples used by Breed (2007, pp. 21-23),
gene flow to GMU 2 appears to be uni-directional, which is consistent
with the movement data from wolves radio-collared in GMU 2 that
demonstrated no emigration from that population (ADFG 2015c, p. 2).
These findings, coupled with the trend of the GMU 2 wolf population
(see ``Abundance and Trend,'' above), suggest that this population may
serve as a sink population of the Alexander Archipelago wolf;
conversely, the northern coastal British Columbian population may be a
source population to southern southeastern Alaska, as suggested by
Breed (2007, p. 34). This hypothesis is supported further with genetic
information indicating a low frequency of private alleles and no unique
haplotypes in the wolves occupying GMU 2. Nonetheless, we recognize
that persistence of this population may be dependent on the health of
adjacent populations (e.g., GMU 3), but conclude that its demographic
and genetic contribution to the rangewide population likely is lower
than other populations such as those in coastal British Columbia.
Ecology
In this section, we briefly describe the ecology, including food
habits, social organization, and space and habitat use, of the
Alexander Archipelago wolf. Again, we review each of these topics in
more detail in the Status Assessment (Service 2015, entire).
Food Habits
Similar to gray wolves, Alexander Archipelago wolves are
opportunistic predators that eat a variety of prey species, although
ungulates compose most of their overall diet. Based on scat and stable
isotope analyses, black-tailed deer (Odocoileus hemionus), moose,
mountain goat (Oreamnos americanus), and elk (Cervus spp.), either
individually or in combination, constitute at least half of the wolf
diet across southeastern Alaska and coastal British Columbia (Fox and
Streveler 1986, pp. 192-193; Smith et al. 1987, pp. 9-11, 16; Milne et
al. 1989, pp. 83-85; Kohira and Rexstad 1997, pp. 429-430; Szepanski et
al. 1999, p. 331; Darimont et al. 2004, p. 1871; Darimont et al. 2009,
p. 130; Lafferty et al. 2014, p. 145). Other prey species regularly
consumed, depending on availability, include American beaver (Castor
canadensis), hoary marmot (Marmota caligata), mustelid species
(Mustelidae spp.), salmon (Oncorhynchus spp.), and marine mammals
(summarized more fully in the Status Assessment, Service 2015, ``Food
habits'').
Prey composition in the diet of the Alexander Archipelago wolf
varies across space and time, usually reflecting availability on the
landscape, especially for ungulate species that are not uniformly
distributed across the islands and mainland. For instance, mountain
goats are restricted to the mainland and Revillagigedo Island
(introduced). Similarly, moose occur along the mainland and nearby
islands as well as most of the islands in GMU 3 (e.g., Kuiu, Kupreanof,
Mitkof, and Zarembo islands); moose distribution is expanding in
southeastern Alaska and coastal British Columbia (Darimont et al. 2005,
p. 235; Hundertmark et al. 2006, p. 331). Elk also occur only on some
islands in southeastern Alaska (e.g., Etolin Island) and on Vancouver
Island. Deer are the only ungulate distributed throughout the range of
the Alexander Archipelago wolf, although abundance varies greatly with
snow conditions. Generally, deer are abundant in southern coastal
British Columbia, where the climate is mild, with their numbers
decreasing northward along the mainland due to increasing snow depths,
although they typically occur in high densities on islands such as POW,
where persistent and deep snow accumulation is less common.
Owing to the disparate patterns of ungulate distribution and
abundance, some Alexander Archipelago wolf populations have a more
restricted diet than others. For example, in GMU 2, deer is the only
ungulate species available to wolves, but elsewhere moose, mountain
goat, elk, or a combination of these ungulates are available. Szepanski
et al. (1999, pp. 330-331) demonstrated that deer and salmon
contributed equally to the diet of wolves on POW (GMU 2), Kupreanof
Island (GMU 3), and the mainland (GMUs 1A and 1B) (deer = 45-49 percent
and salmon = 15-20 percent), and that ``other herbivores'' composed the
remainder of the diet (34-36 percent). On POW, ``other herbivores''
included only beaver and voles (Microtus spp.), but on Kupreanof
Island, moose also was included, and on the mainland, mountain goat was
added
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to the other two herbivore prey species. Therefore, we hypothesize that
wolves in GMU 2, and to a lesser extent in parts of GMU 3, are more
vulnerable to changes in deer abundance compared to other wolf
populations that have a more diverse ungulate prey base available to
them.
Given the differences in prey availability throughout the range of
the Alexander Archipelago wolf, some general patterns in their food
habits exist. On the northern mainland of southeastern Alaska, where
deer occur in low densities, wolves primarily eat moose and mountain
goat (Fox and Streveler 1986, pp. 192-193; Lafferty et al. 2014, p.
145). As one moves farther south and deer become more abundant, they
are increasingly represented in the diet, along with correspondingly
smaller proportions of moose and mountain goat where available
(Szepanski et al. 1999, p. 331; Darimont et al. 2004, p. 1869). On the
outer islands of coastal British Columbia, marine mammals compose a
larger portion of the diet compared to other parts of the range of the
Alexander Archipelago wolf (Darimont et al. 2009, p. 130); salmon
appear to be eaten regularly by coastal wolves in low proportions (less
than 20 percent), although some variation among populations exists.
Generally, the diet of wolves in coastal British Columbia appears to be
more diverse than in southeastern Alaska (e.g., Kohira and Rexstad
1997, pp. 429-430; Darimont et al. 2004, pp. 1869, 1871), consistent
with a more diverse prey base in the southern portion of the range of
the Alexander Archipelago wolf. We review these diet studies and others
in the Status Assessment (Service 2015, ``Food habits'').
One of the apparently unusual aspects of the Alexander Archipelago
wolf diet is consumption of marine-derived foods. However, we found
evidence suggesting that this behavior is not uncommon for gray wolves
in coastal areas or those that have inland access to marine prey (e.g.,
spawning salmon). For example, wolves on the Alaska Peninsula in
western Alaska have been observed catching and eating sea otters
(Enhydra lutris), using offshore winter sea ice as a hunting platform
and feeding on marine mammal carcasses such as Pacific walrus (Odobenus
rosmarus divergens) and beluga whale (Delphinapterus leucas) (Watts et
al. 2010, pp. 146-147). In addition, Adams et al. (2010, p. 251) found
that inland wolves in Denali National Park, Alaska, ate salmon in
slightly lower but similar quantities (3-17 percent of lifetime diet)
compared to Alexander Archipelago wolves (15-20 percent of lifetime
diet; Szepanski et al. 1999, p. 327). These findings and others suggest
that marine-derived resources are not a distinct component of the diet
of the Alexander Archipelago wolf. Nonetheless, marine prey provide
alternate food resources to coastal wolves during periods of the year
with high food and energy demands (e.g., provisioning of pups when
salmon are spawning; Darimont et al. 2008, pp. 5, 7-8) and when and
where abundance of terrestrial prey is low.
Social Organization
Wolves are social animals that live in packs usually composed of
one breeding pair (i.e., alpha male and female) plus offspring of 1 to
2 years old. The pack is a year-round unit, although all members of a
wolf pack rarely are observed together except during winter (Person et
al. 1996, p. 7). Loss of alpha members of a pack can result in social
disruption and unstable pack dynamics, which are complex and shift
frequently as individuals age and gain dominance, disperse from,
establish or join existing packs, breed, and die (Mech 1999, pp. 1197-
1202). Although loss of breeding individuals impacts social stability
within the pack, at the population level wolves appear to be resilient
enough to compensate for any negative impacts to population growth
(Borg et al. 2015, p. 183).
Pack sizes of the Alexander Archipelago wolf are difficult to
estimate owing to the heavy vegetative cover throughout most of its
range. In southeastern Alaska, packs range from one to 16 wolves, but
usually average 7 to 9 wolves with larger packs observed in fall than
in spring (Smith et al. 1987, pp. 4-7; Person et al. 1996, p. 7; ADFG
2015c, p. 2). Our review of the best available information did not
reveal information on pack sizes from coastal British Columbia.
Space and Habitat Use
Similar to gray wolves in North America, the Alexander Archipelago
wolf uses a variety of habitat types and is considered a habitat
generalist (Person and Ingle 1995, p. 30; Mech and Boitani 2003, p.
xv). Person (2001, pp. 62-63) reported that radiocollared Alexander
Archipelago wolves spent most of their time at low elevation during all
seasons (95 percent of locations were below 1,312 feet [ft] [400 m] in
elevation), but did not select for or against any habitat types except
during the pup-rearing season. During the pup-rearing season,
radiocollared wolves selected for open- and closed-canopy old-growth
forests close to lakes and streams and avoided clearcuts and roads
(Person 2001, p. 62), a selection pattern that is consistent with den
site characteristics.
Alexander Archipelago wolves den in root wads of large living or
dead trees in low-elevation, old-growth forests near freshwater and
away from logged stands and roads, when possible (Darimont and Paquet
2000, pp. 17-18; Person and Russell 2009, pp. 211, 217, 220). Of 25
wolf dens monitored in GMU 2, the majority (67 percent) were located
adjacent to ponds or streams with active beaver colonies (Person and
Russell 2009, p. 216). Although active dens have been located near
clearcuts and roads, researchers postulate that those dens probably
were used because suitable alternatives were not available (Person and
Russell 2009, p. 220).
Home range sizes of Alexander Archipelago wolves are variable
depending on season and geographic location. Generally, home ranges are
about 50 percent smaller during denning and pup-rearing periods
compared to other times of year (Person 2001, p. 55), and are roughly
four times larger on the mainland compared to the islands in
southeastern Alaska (ADFG 2015c, p. 2). Person (2001, pp. 66, 84) found
correlations between home range size, pack size, and the proportion of
``critical winter deer habitat''; he thought that the relation between
these three factors was indicative of a longer-term influence of
habitat on deer density. We review space and habitat use of Alexander
Archipelago wolf and Sitka black-tailed deer, the primary prey item
consumed by wolves throughout most of their range, in detail in the
Status Assessment (Service 2015, ``Space and habitat use'').
Summary of Species Information
In summary, we find that the Alexander Archipelago wolf currently
is distributed throughout most of southeastern Alaska and coastal
British Columbia with a rangewide population estimate of 850-2,700
wolves. The majority of the range (67 percent) and the rangewide
population (approximately 62 percent) occur in coastal British
Columbia, where the population is stable or increasing. In southeastern
Alaska, we found trend information only for the GMU 2 population
(approximately 6 percent of the rangewide population) that indicates a
decline of about 75 (SE = 15) percent since 1994, although variation
around the point estimates (n = 4) was substantial. This apparent
decline is consistent with low estimates of annual survival of wolves
in GMU 2, with the primary source of mortality being harvest by humans.
For the remainder of
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southeastern Alaska (about 32 percent of the rangewide population),
trends of wolf populations are not known.
Similar to the continental gray wolf, the Alexander Archipelago
wolf has several life-history and ecological traits that contribute to
its resiliency, or its ability to withstand stochastic disturbance
events. These traits include high reproductive potential, ability to
disperse long distances (over 100 km), use of a variety of habitats,
and a diverse diet including terrestrial and marine prey. However, some
of these traits are affected by the island geography and rugged terrain
of most of southeastern Alaska and coastal British Columbia. Most
notably, we found that demographic and genetic connectivity of some
populations, specifically the GMU 2 population, is low, probably due to
geographical disruptions to dispersal and gene flow. In addition, not
all prey species occur throughout the range of the Alexander
Archipelago wolf, and, therefore, some populations have a more limited
diet than others despite the opportunistic food habits of wolves.
Specifically, the GMU 2 wolf population is vulnerable to fluctuations
in abundance of deer, the only ungulate species that occupies the area.
We postulate that the insularity of this population, coupled with its
reliance on one ungulate prey species, likely has contributed to its
apparent recent decline, suggesting that, under current conditions, the
traits associated with resiliency may not be sufficient for population
stability in GMU 2.
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 Alexander
Archipelago wolf 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; we then attempt to
determine if that factor rises to the level of a threat, meaning that
it may drive or contribute to the risk of extinction of the species
such that the species warrants listing as an endangered or threatened
species 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, however; 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 Alexander Archipelago wolf uses a variety of habitats and, like
other gray wolves, is considered to be a habitat generalist. Further,
it is an opportunistic predator that eats ungulates, rodents,
mustelids, fish, and marine mammals, typically killing live prey, but
also feeding on carrion if fresh meat is not available or circumstances
are desirable (e.g., large whale carcass). For these reasons and others
(e.g., dispersal capability), we found that wolf populations often are
resilient to changes in their habitat and prey. Nonetheless, we also
recognize that the Alexander Archipelago wolf inhabits a distinct
ecosystem, partially composed of island complexes, that may restrict
wolf movement and prey availability of some populations, thereby
increasing their vulnerability to changes in habitat.
In this section, we review stressors to terrestrial and intertidal
habitats used by the Alexander Archipelago wolf and its primary prey,
specifically deer. We identified timber harvest as the principal
stressor modifying wolf and deer habitat in southeastern Alaska and
coastal British Columbia, and, therefore, we focus our assessment on
this stressor by evaluating possible direct and indirect impacts to the
wolf at the population and rangewide levels. We also consider possible
effects of road development, oil development, and climate-related
events on wolf habitat. We describe the information presented here in
more detail in the Status Assessment (Service 2015, ``Cause and effect
analysis'').
Timber Harvest
Throughout most of the range of the Alexander Archipelago wolf,
timber harvest has altered forested habitats, especially those at low
elevations, that are used by wolves and their prey. Rangewide, we
estimate that 19 percent of the productive old-growth forest has been
logged, although it has not occurred uniformly across the landscape or
over time. A higher percentage of productive old-growth forest has been
logged in coastal British Columbia (24 percent) compared to
southeastern Alaska (13 percent), although in both areas, most of the
harvest has occurred since 1975 (85 percent and 66 percent,
respectively). Within coastal British Columbia, the majority of harvest
(66 percent of total harvest) has happened in Region 1, where 34
percent of the forest has been logged; in the coastal portions of
Regions 2, 5, and 6, timber harvest has been comparatively lower,
ranging from 12 to 17 percent of the productive forest in these
regions. Similarly, in southeastern Alaska, logging has occurred
disproportionately in GMU 2, where 23 percent of the forest has been
logged (47 percent of all timber harvest in southeastern Alaska); in
other GMUs, only 6 to 14 percent of the forest has been harvested. We
discuss spatial and temporal patterns of timber harvest in more detail
in the Status Assessment (Service 2015, ``Timber harvest'').
Owing to past timber harvest in southeastern Alaska and coastal
British Columbia, portions of the landscape currently are undergoing
succession and will continue to do so. Depending on site-specific
conditions, it can take up to several hundred years for harvested
stands to regain old-growth forest characteristics fully (Alaback 1982,
p. 1939). During the intervening period, these young-growth stands
undergo several successional stages that are relevant to herbivores
such as deer. Briefly, for 10 to 15 years following clearcut logging,
shrub and herb biomass production increases (Alaback 1982, p. 1941),
providing short-term benefits to herbivores such as deer, which select
for these stands under certain conditions (e.g., Gilbert 2015, p.
[[Page 444]]
129). After 25 to 35 years, early seral stage plants give way to young-
growth coniferous trees, and their canopies begin to close,
intercepting sunlight and eliminating most understory vegetation. These
young-growth stands offer little nutritional browse for deer and
therefore tend to be selected against by deer (e.g., Gilbert 2015, pp.
129-130); this stage typically lasts for at least 50 to 60 years, at
which point the understory layer begins to develop again (Alaback 1982,
pp. 1938-1939). An understory of deciduous shrubs and herbs, similar to
pre-harvest conditions, is re-established 140 to 160 years after
harvest. Alternative young-growth treatments (e.g., thinning, pruning)
are used to stimulate understory growth, but they often are applied at
small spatial scales, and their efficacy in terms of deer use is
unknown; regardless, to date, over 232 mi\2\ (600 km\2\) of young-
growth has been treated in southeastern Alaska (summarized in Service
2015, ``Timber harvest'').
We expect timber harvesting to continue to occur throughout the
range of the Alexander Archipelago wolf, although given current and
predicted market conditions, the rate of future harvest is difficult to
project. In southeastern Alaska, primarily in GMUs 2 and 3, some timber
has been sold by the USFS already, but has not yet been cut. In
addition, new timber sales currently are being planned for sale between
2015 and 2019, and most of this timber is expected to be sourced from
GMUs 2 and 3; however, based on recent sales, it is unlikely that the
planned harvest will be implemented fully due to lack of bidders. Also,
we anticipate at least partial harvest of approximately 277 km\2\ of
land in GMU 2 that was transferred recently from the Tongass National
Forest to Sealaska Native Corporation. In coastal British Columbia, we
estimate that an additional 17 percent of forest will be harvested by
2100 on Vancouver Island (Region 1) and an additional 39 percent on the
mainland of coastal British Columbia; however, some of this timber
volume would be harvested from old young-growth stands. See the Status
Assessment for more details (Service 2015, ``Future timber harvest'').
Since 2013, the USFS has been developing a plan to transition
timber harvest away from primarily logging old-growth and toward
logging young-growth stands, although small amounts of old-growth
likely will continue to be logged. An amendment to the current Tongass
Land and Resource Management Plan is underway and is expected to be
completed by the end of 2016. Although this transition is expected to
reduce further modification of habitat used by wolves and deer, the
amendment that outlines the transition is still in the planning phase.
Potential Effects of Timber Harvest
After reviewing the best available information, we determined that
the only potential direct effect from timber harvest to Alexander
Archipelago wolves is the modification of and disturbance at den sites.
Although coastal wolves avoided using den sites located in or near
logged stands, other landscape features such as gentle slope, low
elevation, and proximity to freshwater had greater influence on den
site use (Person and Russell 2009, pp. 217-219). Further, our review of
the best available information did not indicate that denning near
logged stands had fitness consequences to individual wolves or that
wolf packs inhabiting territories with intensive timber harvest were
less likely to breed due to reduced availability of denning habitat.
Therefore, we conclude that modification of and disturbance at den
sites as a result of timber harvest does not constitute a threat to the
Alexander Archipelago wolf at the population or rangewide level.
We then examined reduction in prey availability, specifically deer,
as a potential indirect effect of timber harvest to the Alexander
Archipelago wolf. Because deer selectively use habitats that minimize
accumulation of deep snow in winter, including productive old-growth
forest (e.g., Schoen and Kirchhoff, 1990, p. 374; Doerr et al. 2005, p.
322; Gilbert 2015, p. 129), populations of deer in areas of intensive
timber harvest are expected to decline in the future as a result of
long-term reduction in the carrying capacity of their winter habitat
(e.g., Person 2001, p. 79; Gilbert et al. 2015, pp. 18-19). However, we
found that most populations of Alexander Archipelago wolf likely will
be resilient to predicted declines in deer abundance largely owing to
their ability to feed on alternate ungulate prey species and non-
ungulate species, including those that occur in intertidal and marine
habitats (greater than 15 percent of the diet; see ``Food Habits,''
above) (Szepanski et al. 1999, p. 331; Darimont et al. 2004, p. 1871,
Darimont et al. 2009, p. 130). Moreover, in our review of the best
available information, we found nothing to suggest that these
intertidal and marine species, non-ungulate prey, and other ungulate
species within the range of the Alexander Archipelago wolf (i.e.,
moose, goat, elk) are affected significantly by timber harvest (Service
2015, ``Response of wolves to timber harvest''). Therefore, we focus
the remainder of this section on predicted response of wolves to
reduction in deer numbers as a result of timber harvest and
availability of alternate ungulate prey.
In coastal British Columbia, where a greater proportion of
productive old-growth forest has been harvested compared to
southeastern Alaska, deer populations are stable (Regions 1, 2, and 5)
or decreasing (Region 6) (BCMO 2015b, p. 1). Yet, corresponding wolf
populations at the regional scale are stable or slightly increasing
(Kuzyk and Hatter 2014, p. 881; BCMO 2015a, p. 1). We attribute the
stability in wolf numbers, in part, to the availability of other
ungulate species, specifically moose, mountain goat, and elk (Region 1
only), which primarily have stable populations and do not use habitats
affected by timber harvest. Therefore, we presume that these wolf
populations have adequate prey available and are not being affected
significantly by changes in deer abundance as a result of timber
harvest.
Similarly, throughout most of southeastern Alaska, wolves have
access to multiple ungulate prey species in addition to deer. Along the
mainland (GMUs 1 and 5A), where deer densities are low naturally, moose
and mountain goats are available, and, in GMU 3, moose occur on all of
the larger islands and elk inhabit Etolin and Zarembo islands. Also,
although we expect deer abundance in these GMUs to be lower in the
future, deer will continue to be available to wolves; between 1954 and
2002, deer habitat capability was reduced by only 15 percent in parts
of GMU 1 and by 13 to 23 percent in GMU 3 (Albert and Schoen 2007, p.
16). Thus, although we lack estimates of trend in these wolf
populations, we postulate that they have sufficient prey to maintain
stable populations and are not being impacted by timber harvest.
Only one Alexander Archipelago wolf population, the GMU 2
population, relies solely on deer as an ungulate prey species and
therefore it is more vulnerable to declines in deer numbers compared to
all other populations. Additionally, timber harvest has occurred
disproportionately in this area, more so than anywhere else in the
range of the wolf except Vancouver Island (where the wolf population is
stable). As a result, in GMU 2, deer are projected to decline by
approximately 21 to 33 percent over the next 30 years, and,
correspondingly, the wolf population is predicted to decline by an
average of 8 to 14 percent (Gilbert et al. 2015, pp. 19, 43). Further,
the GMU 2 wolf population already has been reduced by about 75
[[Page 445]]
percent since 1994, although most of the apparent decline occurred over
a 1-year period between 2013 and 2014 (see ``Abundance and Trend,''
above), suggesting that the cause of the decline was not specifically
long-term reduction in deer carrying capacity, although it probably was
a contributor. These findings indicate that for this wolf population,
availability of non-ungulate prey does not appear to be able to
compensate for declining deer populations, especially given other
present stressors such as wolf harvest (see discussion under Factor B).
Therefore, we conclude that timber harvest is affecting the GMU 2 wolf
population by reducing its ungulate prey and likely will continue to do
so in the future.
In reviewing the best available information, we conclude that
indirect effects from timber harvest likely are not having and will not
have a significant effect on the Alexander Archipelago wolf at the
rangewide level. Although timber harvest has reduced deer carrying
capacity, which in turn is expected to cause declines in deer
populations, wolves are opportunistic predators, feeding on a variety
of prey species, including intertidal and marine species that are not
impacted by timber harvest. In addition, the majority (about 94
percent) of the rangewide wolf population has access to ungulate prey
species other than deer. Further, currently the wolf populations in
coastal British Columbia, which constitute 62 percent of the rangewide
population, are stable or slightly increasing despite intensive and
extensive timber harvest.
However, we also conclude that the GMU 2 wolf population likely is
being affected and will continue to be affected by timber harvest, but
that any effects will be restricted to the population level. This wolf
population represents only 6 percent of the rangewide population, is
largely insular and geographically peripheral to other populations, and
appears to function as a sink population (see ``Abundance and Trend''
and ``Dispersal and Connectivity,'' above). For these reasons, we find
that the demographic and genetic contributions of the GMU 2 wolf
population to the rangewide population are low. Thus, although we
expect deer and wolf populations to decline in GMU 2, in part as a
result of timber harvest, we find that these declines will not result
in a rangewide impact to the Alexander Archipelago wolf population.
Road Development
Road development has modified the landscape throughout the range of
the Alexander Archipelago wolf. Most roads were constructed to support
the timber industry, although some roads were built as a result of
urbanization, especially in southern coastal British Columbia. Below,
we briefly describe the existing road systems in southeastern Alaska
and coastal British Columbia using all types of roads (e.g., sealed,
unsealed) that are accessible with any motorized vehicle (e.g.,
passenger vehicle, all-terrain vehicle). See the Status Assessment for
a more detailed description (Service 2015, ``Road construction and
management'').
Across the range of the Alexander Archipelago wolf, the majority
(86 percent) of roads are located in coastal British Columbia
(approximately 41,943 mi [67,500 km] of roads), where mean road density
is 0.76 mi per mi\2\ (0.47 km per km\2\), although road densities are
notably lower in the northern part of the province (Regions 5 and 6,
mean = 0.21-0.48 mi per km\2\ [0.13-0.30 km per km\2\]) compared to the
southern part (Regions 1 and 2, mean = 0.85-0.89 mi per mi\2\ [0.53-
0.55 km per km\2\]), largely owing to the urban areas of Vancouver and
Victoria. In southeastern Alaska, nearly 6,835 mi [11,000 km] of roads
exist within the range of the Alexander Archipelago wolf, resulting in
a mean density of 0.37 mi per mi\2\ (0.23 km per km\2\). Most of these
roads are located in GMU 2, where the mean road density is 1.00 mi per
mi\2\ (0.62 km per km\2\), more than double that in all other GMUs,
where the mean density ranges from 0.06 mi per mi\2\ (0.04 km per
km\2\) (GMU 5A) to 0.42 mi per mi\2\ (0.26 km per km\2\) (GMU 3). Thus,
most of the roads within the range of the Alexander Archipelago wolf
are located in coastal British Columbia, especially in Regions 1 and 2,
but the highest mean road density occurs in GMU 2 in southeastern
Alaska, which is consistent with the high percentage of timber harvest
in this area (see ``Timber Harvest,'' above). In addition, we
anticipate that most future road development also will occur in GMU 2
(46 mi [74 km] of new road), with smaller additions to GMUs 1 and 3
(Service 2015, ``Road construction and management'').
Given that the Alexander Archipelago wolf is a habitat generalist,
we find that destruction and modification of habitat due to road
development likely is not affecting wolves at the population or
rangewide level. In fact, wolves occasionally use roads as travel
corridors between habitat patches (Person et al. 1996, p. 22). As
reviewed above in ``Timber Harvest,'' we recognize that wolves used den
sites located farther from roads compared to unused sites; however,
other landscape features were more influential in den site selection,
and proximity to roads did not appear to affect reproductive success or
pup survival, which is thought to be high (Person et al. 1996, p. 9;
Person and Russell 2009, pp. 217-219). Therefore, we conclude that
roads are not a threat to the habitats used by the Alexander
Archipelago wolf, although we address the access that they afford to
hunters and trappers as a potential threat to some wolf populations
under Factor B.
Oil and Gas Development
We reviewed potential loss of habitat due to oil and gas
development as a stressor to the Alexander Archipelago wolf. We found
no existing oil and gas projects within the range of the coastal wolf,
although two small-scale exploration projects occurred in Regions 1 and
2 of coastal British Columbia, but neither project resulted in
development. In addition, we considered a proposed oil pipeline project
(i.e., Northern Gateway Project) intended to transport oil from Alberta
to the central coast of British Columbia, covering about 746 mi (1,200
km) in distance. If the proposed project was approved and implemented,
risk of oil spills on land and on the coast within the range of the
Alexander Archipelago wolf would exist. However, given its diverse
diet, terrestrial habitat use, and dispersal capability, we conclude
that wolf populations would not be affected by the pipeline project
even if an oil spill occurred because exposure would be low. Further,
oil development occurs in portions of the range of the gray wolf (e.g.,
Trans Alaska Pipeline System) and is not thought to be impacting wolf
populations negatively. We conclude that oil development is not a
threat to the Alexander Archipelago wolf now and is not likely to
become one in the future.
Climate-Related Events
We considered the role of climate and projected changes in climate
as a potential stressor to the Alexander Archipelago wolf. We
identified three possible mechanisms through which climate may be
affecting habitats used by coastal wolves or their prey: (1) Frequency
of severe winters and impacts to deer populations; (2) decreasing
winter snow pack and impacts to yellow cedar; and (3) predicted
hydrologic change and impacts to salmon productivity. We review each of
these briefly here and in
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more detail in the Status Assessment (Service 2015, ``Climate-related
events'').
Severe winters with deep snow accumulation can negatively affect
deer populations by reducing availability of forage and by increasing
energy expenditure associated with movement. Therefore, deer
selectively use habitats in winter that accumulate less snow, such as
those that are at low elevation, that are south-facing, or that can
intercept snowfall (i.e., dense forest canopy). Timber harvest has
reduced some of these preferred winter habitats. However, while
acknowledging that severe winters can result in declines of local deer
populations, we postulate that those declines are unlikely to affect
wolves substantially at the population or rangewide level for several
reasons.
First, in southern coastal British Columbia where 24 percent of the
rangewide wolf population occurs, persistent snowfall is rare except at
high elevations. Second, in GMU 2, where wolves are limited to deer as
ungulate prey and therefore are most vulnerable to declines in deer
abundance, the climate is comparatively mild and severe winters are
infrequent (Shanley et al. 2015, p. 6); Person (2001, p. 54) estimated
that six winters per century may result in general declines in deer
numbers in GMU 2. Lastly, climate projections indicate that
precipitation as snow will decrease by up to 58 percent over the next
80 years (Shanley et al. 2015, pp. 5-6), reducing the likelihood of
severe winters. Therefore, we conclude that winter severity, and
associated interactions with timber harvest, is not a threat to the
persistence of the Alexander Archipelago wolf at the population or
rangewide level now or in the future.
In contrast to deer response to harsh winter conditions, recent and
ongoing decline in yellow cedar in southeastern Alaska is attributed to
warmer winters and reduced snow cover (Hennon et al. 2012, p. 156).
Although not all stands are affected or affected equally, the decline
has impacted about 965 mi\2\ (2,500 km\2\) of forest (Hennon et al.
2012, p. 148), or less than 3 percent of the forested habitat within
the range of the Alexander Archipelago wolf. In addition, yellow cedar
is a minor component of the temperate rainforest, which is dominated by
Sitka spruce and western hemlock and neither of these tree species
appears to be impacted negatively by reduced snow cover (e.g., Schaberg
et al. 2005, p. 2065). Therefore, we conclude that any effects
(positive or negative) to the wolf as a result of loss of yellow cedar
would be negligible given that it constitutes a small portion of the
forest and that the wolf is a habitat generalist.
Predicted hydrologic changes as a result of changes in climate are
expected to reduce salmon productivity within the range of the
Alexander Archipelago wolf (e.g., Edwards et al. 2013, p. 43; Shanley
and Albert 2014, p. 2). Warmer winter temperatures and extreme flow
events are predicted to reduce egg-to-fry survival of salmon, resulting
in lower overall productivity. Although salmon compose 15 to 20 percent
of the lifetime diet of Alexander Archipelago wolves in southeastern
Alaska (Szepanski et al. 1999, pp. 330-331) and 0 to 16 percent of the
wolf diet in coastal British Columbia (Darimont et al. 2004, p. 1871;
Darimont et al. 2009, p. 13) (see ``Food Habits,'' above), we do not
anticipate negative effects to them in response to projected declines
in salmon productivity at the population or rangewide level owing to
the opportunistic predatory behavior of wolves.
Conservation Efforts To Reduce Habitat Destruction, Modification, or
Curtailment of Its Range
We are not aware of any nonregulatory conservation efforts, such as
habitat conservation plans, or other voluntary actions that may help to
ameliorate potential threats to the habitats used by the Alexander
Archipelago wolf.
Summary of Factor A
Although several stressors such as timber harvest, road
development, oil development, and climate-related events may be
impacting some areas within the range of the Alexander Archipelago
wolf, available information does not indicate that these impacts are
affecting or are likely to affect the rangewide population. First and
foremost, wolf populations in coastal British Columbia, where most (62
percent) of the rangewide population occurs, are stable or slightly
increasing even though the landscape has been modified extensively. In
fact, a higher proportion of the forested habitat has been logged (24
percent) and the mean road density (0.76 mi per mi\2\ [0.47 km per
km\2\]) is higher in coastal British Columbia compared to southeastern
Alaska (13 percent and 0.37 mi per mi\2\ [0.23 km per km\2\],
respectively). Second, we found no direct effects of habitat-related
stressors that resulted in lower fitness of Alexander Archipelago
wolves, in large part because the wolf is a habitat generalist. Third,
although deer populations likely will decline in the future as a result
of timber harvest, we found that most wolf populations will be
resilient to reduced deer abundance because they have access to
alternate ungulate and non-ungulate prey that are not impacted
significantly by timber harvest, road development, or other stressors
that have altered or may alter habitat within the range of the wolf.
Only the GMU 2 wolf population likely is being impacted and will
continue to be impacted by reduced numbers of deer, the only ungulate
prey available; however, we determined that this population does not
contribute substantially to the other Alexander Archipelago wolf
populations or the rangewide population. Therefore, we posit that most
(94 percent) of the rangewide population of Alexander Archipelago wolf
likely is not being affected and will not be affected in the future by
loss or modification of habitat.
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 Alexander Archipelago wolf at the rangewide level,
nor is it likely to become a threat in the future.
Factor B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
The Alexander Archipelago wolf is harvested by humans for
commercial and subsistence purposes. Mortality of wolves due to harvest
can be compensated for at the population or rangewide level through
increased survival, reproduction, or immigration (i.e., compensatory
mortality), or harvest mortality may be additive, causing overall
survival rates and population growth to decline. The degree to which
harvest is considered compensatory, partially compensatory, or at least
partially additive is dependent on population characteristics such as
age and sex structure, productivity, immigration, and density (e.g.,
Murray et al. 2010, pp. 2519-2520). Therefore, each wolf population (or
group of populations) is different, and a universal rate of sustainable
harvest does not exist. In our review, we found rates of human-caused
mortality of gray wolf populations varying from 17 to 48 percent, with
most being between 20 and 30 percent (Fuller et al. 2003, pp. 184-185;
Adams et al. 2008, p. 22; Creel and Rotella 2010, p. 5; Sparkman et al.
2011, p. 5; Gude et al. 2012, pp. 113-116). For the Alexander
Archipelago wolf in GMU 2, Person and Russell (2008, p. 1547) reported
that total annual mortality greater than 38 percent was unsustainable
and that natural mortality averaged about 4 percent (SE
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= 5) annually, suggesting that human-caused mortality should not exceed
34 percent annually. In our review, we did not find any other estimates
of sustainable harvest rates specific to the coastal wolf.
Across the range of the Alexander Archipelago wolf, hunting and
trapping regulations, including reporting requirements, vary
substantially. In southeastern Alaska, wolf harvest regulations are set
by the Alaska Board of Game for all resident and nonresident hunters
and trappers, and by the Federal Subsistence Board for federally-
qualified subsistence users on Federal lands. In all GMUs, each hunter
can harvest a maximum of five wolves, and trappers can harvest an
unlimited number of wolves; all harvested wolves must be reported and
sealed within a specified time following harvest. In GMU 2 only, an
annual harvest guideline is applied; between 1997 and 2014, the harvest
guideline was set as 25 to 30 percent of the most recent fall
population estimate, and in 2015, this guideline was reduced to 20
percent in response to an apparent decline in the population (see
``Abundance and Trend,'' above). If the annual harvest guideline is
exceeded, then an emergency order closing the hunting and trapping
seasons is issued. In coastal British Columbia, the provincial
government manages wolf harvest, following an established management
plan. The hunting bag limit is three wolves per hunter annually, and,
similar to southeastern Alaska, no trapping limit is set. In Regions 1
and 2, all wolf harvest is required to be reported, but no compulsory
reporting program exists for Regions 5 and 6.
In this section, we consider wolf harvest as a stressor to the
Alexander Archipelago wolf at the population and rangewide levels.
Given that harvest regulations and the biological circumstances (e.g.,
degree of insularity; see ``Dispersal and Connectivity,'' above) of
each wolf population vary considerably, we examined possible effects of
wolf harvest to each population by first considering the current
condition of the population. If the population is stable or increasing,
we presumed that wolves in that population are not being overharvested;
if the population is declining or unknown, we assessed mean annual
harvest rates based on reported wolf harvest. Because some wolves are
harvested and not reported, even in areas where reporting is required,
we then applied proportions of unreported harvest to reported harvest
for a given year to estimate total harvest, where it was appropriate to
do so. We used the population-level information collectively to
evaluate impacts of total harvest to the rangewide population of the
Alexander Archipelago wolf. We present our analyses and other
information related to wolf harvest in southeastern Alaska and coastal
British Columbia in more detail in the Status Assessment (Service 2015,
``Wolf harvest'').
In coastal British Columbia, populations of the Alexander
Archipelago wolf are considered to be stable or slightly increasing
(see ``Abundance and Trend,'' above), and, therefore, we presume that
current harvest levels are not impacting those populations. Moreover,
in Regions 1 and 2, where reporting is required, few wolves are being
harvested on average relative to the estimated population size; in
Region 1, approximately 8 percent of the population was harvested
annually on average between 1997 and 2012, and in Region 2, the rate is
even lower (4 percent). It is more difficult to assess harvest in
Regions 5 and 6 because reporting is not required; nonetheless, based
on the minimum number of wolves harvested annually from these regions,
we estimated that 2 to 7 percent of the populations are harvested on
average with considerable variation among years, which could be
attributed to either reporting or harvest rates. Overall, we found no
evidence indicating that harvest of wolves in coastal British Columbia
is having a negative effect on the Alexander Archipelago wolf at the
population level and is not likely to have one in the future.
In southeastern Alaska, the GMU 2 wolf population apparently has
declined considerably, especially in recent years, although the
precision of individual point estimates was low and the confidence
intervals overlapped (see ``Abundance and Trend,'' above). In our
review, we found compelling evidence to suggest that wolf harvest
likely contributed to this apparent decline. Although annual reported
harvest of wolves in GMU 2 equated to only about 17 percent of the
population on average between 1997 and 2014 (range = 6-33 percent),
documented rates of unreported harvest (i.e., illegal harvest) over a
similar time period were high (approximately 38 to 45 percent of total
harvest) (Person and Russell 2008, p. 1545; ADFG 2015b, p. 4). Applying
these unreported harvest rates, we estimate that mean total annual
harvest was 29 percent with a range of 11 to 53 percent, suggesting
that in some years, wolves in GMU 2 were being harvested at
unsustainable rates; in fact, in 7 of 18 years, total wolf harvest
exceeded 34 percent of the estimated population (following Person and
Russell [2008, p. 1547], and accounting for natural mortality),
suggesting that harvest likely contributed to or caused the apparent
population decline. In addition, it is unlikely that increased
reproduction and immigration alone could reverse the decline, at least
in the short term, owing to this population's insularity (see
``Dispersal and Connectivity,'' above) and current low proportion of
females (see ``Abundance and Trend,'' above). Thus, we conclude that
wolf harvest has impacted the GMU 2 wolf population and, based on the
best available information, likely will continue to do so in the near
future, consistent with a projected overall population decline on
average of 8 to 14 percent (Gilbert et al. 2015, pp. 43, 50), unless
total harvest is curtailed.
Trends in wolf populations in the remainder of southeastern Alaska
are not known, and, therefore, to evaluate potential impact of wolf
harvest to these populations, we reviewed reported wolf harvest in
relation to population size and considered whether or not the high
rates of unreported harvest in GMU 2 were applicable to populations in
GMUs 1, 3, and 5A. Along the mainland (GMUs 1 and 5A) between 1997 and
2014, mean percent of the population harvested annually and reported
was 19 percent (range = 11-27), with most of the harvest occurring in
the southern portion of the mainland. In GMU 3, the same statistic was
21 percent, ranging from 8 to 37 percent, but with only 3 of 18 years
exceeding 25 percent. Thus, if reported harvested rates from these
areas are accurate, wolf harvest likely is not impacting wolf
populations in GMUs 1, 3, and 5A because annual harvest rates typically
are within sustainable limits identified for populations of gray wolf
(roughly 20 to 30 percent), including the Alexander Archipelago wolf
(approximately 34 percent) (Fuller et al. 2003, pp. 184-185; Adams et
al. 2008, p. 22; Person and Russell 2008, p. 1547; Creel and Rotella
2010, p. 5; Sparkman et al. 2011, p. 5; Gude et al. 2012, pp. 113-116).
In our review, we found evidence indicating that unreported harvest
occasionally occurs in GMUs 1 and 3 (Service 2015, ``Unreported
harvest''), but we found nothing indicating that it is occurring at the
high rates documented in GMU 2.
Harvest rates of wolves in southeastern Alaska are associated with
access afforded primarily by boat and motorized vehicle (85 percent of
successful hunters and trappers) (ADFG 2012, ADFG 2015d). Therefore, we
considered road density, ratio of
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shoreline to land area, and the total number of communities as proxies
to access by wolf hunters and trappers and determined that GMU 2 is not
representative of the mainland (GMUs 1 and 5A) or GMU 3 and that
applying unreported harvest rates from GMU 2 to other wolf populations
is not appropriate. Mean road density in GMU 2 (1.00 mi per mi\2\ [0.62
km per km\2\]) is more than twice that of all other GMUs (GMU 1 = 0.13
[0.08], GMU 3 = 0.42 [0.26], and GMU 5A = 0.06 [0.04]). Similarly,
nearly all (13 of 15, 87 percent) of the Wildlife Analysis Areas
(smaller spatial units that comprise each GMU) that exceed the
recommended road density threshold for wolves (1.45 mi per mi\2\ [0.9
km per km\2\]) (Person and Russell 2008, p. 1548) are located in GMU 2;
one each occurs in GMUs 1 and 3. In addition, the ratio of shoreline to
land area, which serves as an indicator of boat acess, in GMU 2 (1.30
mi per mi\2\ [0.81 km per km\2\]) is greater than all other GMUs (GMU 1
= 0.29 [0.18], GMU 3 = 1.00 [0.62], and GMU 5A = 0.19 [0.12]). Lastly,
although the human population size of GMU 2 is comparatively smaller
than in the other GMUs, 14 communities are distributed throughout the
unit, more than any other GMU (GMU 1 = 11, GMU 3 = 4, and GMU 5A = 1).
Collectively, these data indicate that hunting and trapping access
is greater in GMU 2 than in the rest of southeastern Alaska and that
applying unreported harvest rates from GMU 2 to elsewhere is not
supported. Therefore, although we recognize that some level of
unreported harvest likely is occurring along the mainland of
southeastern Alaska and in GMU 3, we do not know the rate at which it
may be occurring, but we hypothesize that it likely is less than in GMU
2 because of reduced access. We expect wolf harvest rates in the future
to be similar to those in the past because we have no basis from which
to expect a change in hunter and trapper effort or success.
Consequently, we think that reported wolf harvest rates for GMUs 1, 3,
and 5A are reasonably accurate and that wolf harvest is not impacting
these populations nor is it likely to do so in the future.
In summary, we find that wolf harvest is not affecting most
populations of the Alexander Archipelago wolf. In coastal British
Columbia, wolf populations are stable or slightly increasing,
suggesting that wolf harvest is not impacting those populations; in
addition, mean annual harvest rates of those populations appear to be
low (2 to 8 percent of the population based on the best available
information). In southeastern Alaska, we determined that the GMU 2 wolf
population is being affected by intermediate rates of reported harvest
(annual mean = 17 percent) and high rates of unreported harvest (38 to
45 percent of total harvest), which have contributed to an apparent
population decline that is projected to continue. We also find that
wolf populations in GMUs 1, 3, and 5A experience intermediate rates of
reported harvest, 19 to 21 percent of the populations annually, but
that these populations likely do not experience high rates of
unreported harvest like those estimated for GMU 2 because of
comparatively low access to hunters and trappers. In addition, these
GMUs are less geographically isolated than GMU 2 and likely have higher
immigration rates of wolves. Therefore, based on the best available
information, we conclude that wolf harvest of these populations (GMUs
1, 3, and 5A) is occurring at rates similar to or below sustainable
harvest rates proposed for gray wolf (roughly 20 to 30 percent) and the
Alexander Archipelago wolf (approximately 34 percent) (Fuller et al.
2003, pp. 184-185; Adams et al. 2008, p. 22; Person and Russell 2008,
p. 1547; Creel and Rotella 2010, p. 5; Sparkman et al. 2011, p. 5; Gude
et al. 2012, pp. 113-116).
Although wolf harvest is affecting the GMU 2 wolf population and
likely will continue to do so, we conclude that wolf harvest is not
impacting the rangewide population of Alexander Archipelago wolf. The
GMU 2 wolf population constitutes a small percentage of the rangewide
population (6 percent), is largely insular and geographically
peripheral to other populations, and appears to function as a sink
population (see ``Abundance and Trend'' and ``Dispersal and
Connectivity,'' above). Therefore, although we found that this
population is experiencing unsustainable harvest rates in some years,
owing largely to unreported harvest, we think that the condition of the
GMU 2 population has a minor effect on the condition of the rangewide
population. The best available information does not suggest that wolf
harvest is having an impact on the rangewide population of Alexander
Archipelago wolf, nor is it likely to have an impact in the future.
Our review of the best available information does not suggest that
overexploitation of the Alexander Archipelago wolf due to scientific or
educational purposes is occurring or is likely to occur in the future.
Conservation Efforts To Reduce Overutilization for Commercial,
Recreational, Scientific, or Educational Purposes
The ADFG has increased educational efforts with the public,
especially hunters and trappers, in GMU 2 with the goal of improving
communication and coordination regarding management of the wolf
population. In recent years, the agency held public meetings, launched
a newsletter, held a workshop for teachers, and engaged locals in wolf
research. We do not know if these efforts ultimately will be effective
at lowering rates of unreported harvest.
We are not aware of any additional conservation efforts or other
voluntary actions that may help to reduce overutilization for
commercial, recreational, scientific, or educational purposes of the
Alexander Archipelago wolf.
Summary of Factor B
We find that wolf harvest is not affecting most Alexander
Archipelago wolf populations. In coastal British Columbia, wolf harvest
rates are low and are not impacting wolves at the population level, as
evidenced by stable or slightly increasing populations. In southeastern
Alaska, we found that the GMU 2 wolf population is experiencing high
rates of unreported harvest, which has contributed to an apparent
population decline, and, therefore, we conclude that this population is
being affected by wolf harvest and likely will continue to be affected.
We determined that wolf harvest in the remainder of southeastern Alaska
is occurring at rates that are unlikely to result in population-level
declines. Overall, we found that wolf harvest is not having an effect
on the Alexander Archipelago wolf at the rangewide level, although we
recognize that the GMU 2 population likely is being harvested at
unsustainable rates, especially given other stressors facing the
population (e.g., reduced prey availability due to timber harvest).
Thus, based on the best available information, we conclude that
overexploitation for commercial, recreational, scientific, or
educational purposes does not currently pose a threat to the Alexander
Archipelago wolf throughout its range, nor is it likely to become a
threat in the future.
Factor C. Disease or Predation
In this section, we briefly review disease and predation as
stressors to the Alexander Archipelago wolf. We describe information
presented here in more detail in the Status Assessment (Service 2015,
``Disease'').
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Disease
Several diseases have potential to affect Alexander Archipelago
wolf populations, especially given their social behavior and pack
structure (see ``Social Organization,'' above). Wolves are susceptible
to a number of diseases that can cause mortality in the wild, including
rabies, canine distemper, canine parvovirus, blastomycosis,
tuberculosis, sarcoptic mange, and dog louse (Brand et al. 1995, pp.
419-422). However, we found few incidences of diseases reported in
Alexander Archipelago wolves; these include dog louse in coastal
British Columbia (Hatler et al. 2008, pp. 88-91) and potentially
sarcoptic mange (reported in British Columbia, but it is unclear
whether or not it occurred along the coast or inland; Miller et al.
2003, p. 183). Both dog louse and mange results in mortality only in
extreme cases and usually in pups, and, therefore, it is unlikely that
either disease is having or is expected to have a population- or
rangewide-level effect on the Alexander Archipelago wolf.
Although we found few reports of diseases in Alexander Archipelago
wolves, we located records of rabies, canine distemper, and canine
parvovirus in other species in southeastern Alaska and coastal British
Columbia, suggesting that transmission is possible but unlikely given
the low number of reported incidences. Only four individual bats have
tested positive for rabies in southeastern Alaska since the 1970s; bats
also are reported to carry rabies in British Columbia, but we do not
know whether or not those bats occur on the coast or inland. Canine
distemper and parvovirus have been found in domestic dogs on rare
occasions; we found only one case of canine distemper, and information
suggested that parvovirus has been documented but is rare due to the
high percentage of dogs that are vaccinated for it. Nonetheless, we
found no documented cases of rabies, canine distemper, or canine
parvovirus in wolves from southeastern Alaska or coastal British
Columbia.
We acknowledge that diseases such as canine distemper and
parvovirus have affected gray wolf populations in other parts of North
America (Brand et al. 1995, p. 420 and references therein), but the
best available information does not suggest that disease, or even the
likelihood of disease in the future, is a threat to the Alexander
Archipelago wolf. We conclude that, while some individual wolves may be
affected by disease on rare occasions, disease is not having a
population- or rangewide-level effect on the Alexander Archipelago wolf
now or in the future.
Predation
Our review of the best available information did not indicate that
predation is affecting or will affect the Alexander Archipelago wolf at
the population or rangewide level. As top predators in the ecosystem,
predation most likely would occur by another wolf as a result of inter-
or intra-pack strife or other territorial behavior. The annual rate of
natural mortality, which includes starvation, disease, and predation,
was 0.04 (SE = 0.05) for radio-collared wolves in GMU 2 (Person and
Russell 2008, p. 1545), indicating that predation is rare and is
unlikely to be having a population or rangewide effect. Therefore, we
conclude that predation is not a threat to the Alexander Archipelago
wolf, nor is it likely to become one in the future.
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 Alexander
Archipelago wolf.
Summary of Factor C
We identified several diseases with the potential to affect wolves
and possible vectors for transmission, but we found only a few records
of disease in individual Alexander Archipelago wolves, and, to the best
of our knowledge, none resulted in mortality. Further, we found no
evidence that disease is affecting the Alexander Archipelago wolf at
the population or rangewide level. Therefore, we conclude that disease
is not a threat to the Alexander Archipelago wolf and likely will not
become a threat in the future.
We also determined that the most likely predator of individual
Alexander Archipelago wolves is other wolves and that this type of
predation is a component of their social behavior and organization.
Further, predation is rare and is unlikely to be having an effect at
population or rangewide levels. Thus, we conclude that predation is not
a threat to the Alexander Archipelago wolf, nor is it likely to become
one in the future.
Factor D. The Inadequacy of Existing Regulatory Mechanisms
In this section, we review laws aimed to help reduce stressors to
the Alexander Archipelago wolf and its habitats. However, because we
did not find any stressors examined under Factors A, B, and C
(described above) and Factor E (described below) to rise to the level
of a threat to the Alexander Archipelago wolf rangewide, we also did
not find the existing regulatory mechanisms authorized by these laws to
be inadequate for the Alexander Archipelago wolf. In other words, we
cannot find an existing regulatory mechanism to be inadequate if the
stressor intended to be reduced by that regulatory mechanism is not
considered a threat to the Alexander Archipelago wolf. Nonetheless, we
briefly discuss relevant laws and regulations below.
Southeastern Alaska
National Forest Management Act (NFMA)
The National Forest Management Act (NFMA; 16 U.S.C. 1600 et seq.)
is the primary statute governing the administration of National Forests
in the United States, including the Tongass National Forest. The stated
objective of NFMA is to maintain viable, well-distributed wildlife
populations on National Forest System lands. As such, the NFMA requires
each National Forest to develop, implement, and periodically revise a
land and resource management plan to guide activities on the forest.
Therefore, in southeastern Alaska, regulation of timber harvest and
associated activities is administered by the USFS under the current
Tongass Land and Resource Management Plan that was signed and adopted
in 2008.
The 2008 Tongass Land and Resource Management Plan describes a
conservation strategy that was developed originally as part of the 1997
Plan with the primary goal of achieving objectives under the NFMA.
Specifically, the conservation strategy focused primarily on
maintaining viable, well-distributed populations of old-growth
dependent species on the Tongass National Forest, because these species
were considered to be most vulnerable to timber harvest activities on
the forest. The Alexander Archipelago wolf, as well as the Sitka black-
tailed deer, was used to help design the conservation strategy. Primary
components of the strategy include a forest-wide network of old-growth
habitat reserves linked by connecting corridors of forested habitat,
and a series of standards and guidelines that direct management of
lands available for timber harvest and other activities outside of the
reserves. We discuss these components in more detail in the Status
Assessment (Service 2015, ``Existing conservation mechanisms'').
As part of the conservation strategy, we identified two elements
specific to the Alexander Archipelago wolf (USFS 2008a, p. 4-95). The
first addresses
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disturbance at and modification of active wolf dens, requiring buffers
of 366 m (1,200 ft) around active dens (when known) to reduce risk of
abandonment, although if a den is inactive for at least 2 years, this
requirement is relaxed. The second pertains to elevated wolf mortality;
in areas where wolf mortality concerns have been identified, a Wolf
Habitat Management Program will be developed and implemented, in
conjunction with ADFG; such a program might include road access
management and changes to wolf harvest limit guidelines. However, this
element, as outlined in the Plan, does not offer guidance on
identifying how, when, or where wolf mortality concerns may exist, but
instead it is left to the discretion of the agencies. The only other
specific elements relevant to the Alexander Archipelago wolf in the
strategy are those that relate to providing sufficient deer habitat
capability, which is intended first to maintain sustainable wolf
populations, then to consider meeting estimated human deer harvest
demands. The strategy offers guidelines for determining whether deer
habitat capability within a specific area is sufficient or not.
We find the 2008 Tongass Land and Resource Management Plan,
including the conservation strategy, not to be inadequate as a
regulatory mechanism aimed to reduce stressors to the Alexander
Archipelago wolf and its habitats. Although some parts of the Tongass
National Forest have sustained high rates of logging in the past, the
majority of it occurred prior to the enactment of the Plan and the
conservation strategy. We think that the provisions included in the
current Plan are sufficient to maintain habitat for wolves and their
prey, especially given that none of the stressors evaluated under
Factors A, B, C, and E constitutes a threat to the Alexander
Archipelago wolf.
However, we recognize that some elements of the Plan have not been
implemented fully yet, as is required under the NFMA. For example,
despite evidence of elevated mortality of wolves in GMU 2 (see
discussion under Factor B, above), the USFS and ADFG have not developed
and implemented a Wolf Habitat Management Program for GMU 2 to date.
The reason for not doing so is because the agencies collectively have
not determined that current rates of wolf mortality in GMU 2
necessitate concern for maintaining a sustainable wolf population.
Although we think that a Wolf Habitat Management Program would benefit
the GMU 2 wolf population, we do not view the lack of it as enough to
deem the entire Plan, or the existing regulatory mechanisms driving it,
to be inadequate for the Alexander Archipelago wolf rangewide. Thus, we
conclude that the 2008 Tongass Land and Resource Management Plan is not
inadequate to maintain high-quality habitat for the Alexander
Archipelago wolf and its prey.
Roadless Rule
On January 12, 2001, the USFS published a final rule prohibiting
road construction and timber harvesting in ``inventoried roadless
areas'' on all National Forest System lands nationwide (hereafter
Roadless Rule) (66 FR 3244). On the Tongass National Forest, 109
roadless areas have been inventoried, covering approximately 14,672
mi\2\ (38,000 km\2\), although only 463 mi\2\ (1,200 km\2\) of these
areas have been described as ``suitable forest land'' for timber
harvest (USFS 2008a, p. 7-42; USFS 2008b, pp. 3-444, 3-449). All of
these roadless areas are located within the range of the Alexander
Archipelago wolf. However, the Roadless Rule was challenged in court
and currently a ruling has not been finalized and additional legal
challenges are pending; in the meantime, the Tongass is subject to the
provisions in the Roadless Rule, although the outcome of these legal
challenges is uncertain. Thus, currently, the Roadless Rule protects
14,672 mi\2\ (38,000 km\2\) of land, including 463 mi\2\ (1,200 km\2\)
of productive forest, from timber harvest, road construction, and other
development, all of which is within the range of the Alexander
Archipelago wolf.
State Regulations
The Alaska Board of Game sets wolf harvest regulations for all
resident and nonresident hunters and trappers, and the ADFG implements
those regulations. (However, for federally-qualified subsistence users,
the Federal Subsistence Board sets regulations, and those regulations
are applicable only on Federal lands.) Across most of southeastern
Alaska, State regulations of wolf harvest appear not to be resulting in
overutilization of the Alexander Archipelago wolf (see discussion under
Factor B, above). However, in GMU 2, wolf harvest is having an effect
on the population, which apparently has declined over the last 20 years
(see ``Abundance and Trend,'' above). Although the population decline
likely was caused by multiple stressors acting synergistically (see
Cumulative Effects from Factors A through E, below), overharvest of
wolves in some years was a primary contributor, suggesting that the
wolf harvest regulations for GMU 2 have been allowing for greater
numbers to be harvested than would be necessary to maintain a viable
wolf population.
In March 2014, ADFG and the USFS, Tongass National Forest, as the
in-season manager for the Federal Subsistence Program, took emergency
actions to close the wolf hunting and trapping seasons in GMU 2, yet
the population still declined between fall 2013 and fall 2014, likely
due to high levels of unreported harvest (38 to 45 percent of total
harvest, summarized under Factor B, above). In early 2015, the agencies
issued another emergency order and, in cooperation with the Alaska
Board of Game, adopted a more conservative wolf harvest guideline for
GMU 2, but an updated population estimate is not available yet, and,
therefore, we do not know if the recent change in regulation has been
effective at avoiding further population decline. Therefore, based on
the best available information, we think that wolf harvest regulations
in GMU 2 are inadequate to avoid exceeding sustainable harvest levels
of Alexander Archipelago wolves, at least in some years. In order to
avoid future unsustainable harvest of wolves in GMU 2, regulations
should consider total harvest of wolves, including loss of wounded
animals, not just reported harvest. Although we found that regulations
governing wolf harvest in GMU 2 have been inadequate, we do not expect
their inadequacy to impact the rangewide population of Alexander
Archipelago wolf for reasons outlined under Factor B, above.
The Alexander Archipelago wolf receives no special protection as an
endangered species or species of concern by the State of Alaska (AS
16.20.180). However, in the draft State Wildlife Action Plan, which is
not yet finalized, the Alexander Archipelago wolf is identified as a
``species of greatest conservation need'' because it is a species for
which the State has high stewardship responsibility and it is
culturally and ecologically important (ADFG 2015e, p. 154).
Coastal British Columbia
In coastal British Columbia, populations of the Alexander
Archipelago wolf have been stable or slightly increasing for the last
15 years (see ``Abundance and Trend,'' above). Nonetheless, we
identified several laws that ensure its continued protection such as
the Forest and Range Practices Act (enacted in 2004), Wildlife Act of
British Columbia (amended in 2008), Species at Risk Act, Federal
Fisheries Act, Convention on International Trade in Endangered Species
of Wild Fauna
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and Flora (CITES), and other regional land use and management plans. We
review these laws in more detail in the Status Assessment (Service
2015, ``Existing conservation measures'').
In 1999, the gray wolf was designated as ``not at risk'' by the
Committee on the Status of Endangered Wildlife in Canada, because it
has a widespread, large population with no evidence of a decline over
the last 10 years (BCMO 2014, p. 2). In British Columbia, the gray wolf
is ranked as ``apparently secure'' by the Conservation Data Centre and
is on the provincial Yellow list, which indicates ``secure.'' We note
here that Canada does not recognize the Alexander Archipelago wolf as a
subspecies of gray wolf that occupies coastal British Columbia, and,
therefore, these designations are applicable to the province or country
scale.
Summary of Factor D
The laws described above regulate timber harvest and associated
activities, protect habitat, minimize disturbance at den sites, and aim
to ensure sustainable harvest of Alexander Archipelago wolves in
southeastern Alaska and coastal British Columbia. As discussed under
Factors A, B, C, and E, although we recognize that some stressors such
as timber harvest and wolf harvest are having an impact on the GMU 2
wolf population, we have not identified any threat that would affect
the taxon as a whole at the rangewide level. Therefore, we find that
the existing regulatory mechanisms authorized by the laws described
above are not inadequate for the rangewide population of the Alexander
Archipelago wolf now and into the future.
Factor E. Other Natural or Manmade Factors Affecting Its Continued
Existence
In this section, we consider other natural or manmade factors that
may be affecting the continued persistence of the Alexander Archipelago
wolf and were not addressed in Factors A through D above. Specifically,
we examined effects of small and isolated populations, hybridization
with dogs, and overexploitation of salmon runs.
Small and Isolated Population Effects
In the petition, island endemism was proposed as a possible
stressor to the Alexander Archipelago wolf. An endemic is a distinct,
unique organism found within a restricted area or range; a restricted
range may be an island, or group of islands, or a restricted region
(Dawson et al. 2007, p. 1). Although small, isolated populations are
more vulnerable to extinction than larger ones due to demographic
stochasticity, environmental variability, genetic problems, and
catastrophic events (Lande 1993, p. 921), endemism or ``rarity'' alone
is not a stressor. Therefore, we instead considered possible effects
associated with small and isolated populations of the Alexander
Archipelago wolf.
Several aspects of the life history of the Alexander Archipelago
wolf result in it being resilient to effects associated with small and
isolated populations. First, the coastal wolf is distributed across a
broad range and is not concentrated in any one area, contributing to
its ability to withstand catastrophic events, which typically occur at
small scales (e.g., wind-caused disturbance) in southeastern Alaska and
coastal British Columbia. Second, the Alexander Archipelago wolf is a
habitat and diet generalist with high reproductive potential and high
dispersal capability in most situations, making it robust to
environmental and demographic variability. However, owing to the island
geography and steep, rugged terrain within the range of the Alexander
Archipelago wolf, some populations are small (fewer than 150 to 250
individuals, following Carroll et al. 2014, p. 76) and at least
partially isolated, although most are not. Nonetheless, we focus the
remainder of this section on possible genetic consequences to small,
partially isolated populations of the Alexander Archipelago wolf.
The primary genetic concern of small, isolated wolf populations is
inbreeding, which, at extreme levels, can reduce litter size and
increase incidence of skeletal effects (e.g., Liberg et al. 2005, p.
17; Raikkonen et al. 2009, p. 1025). We found only one study that
examined inbreeding in the Alexander Archipelago wolf. Breed (2007, p.
18) tested for inbreeding using samples from Regions 5 and 6 in
northern British Columbia and GMUs 1 and 2 in southern southeastern
Alaska, and found that inbreeding coefficients were highest for wolves
in GMU 1, followed by GMU 2, then by Regions 5 and 6. This finding was
unexpected given that GMU 2 is the smaller, more isolated population,
indicating that inbreeding likely is not affecting the GMU 2 population
despite its comparatively small size and insularity. Further, we found
no evidence of historic or recent genetic bottlenecking in the
Alexander Archipelago wolf (Weckworth et al. 2005, p. 924; Breed 2007,
p. 18), although Weckworth et al. (2011, p. 5) speculated that a severe
bottleneck may have taken place long ago (over 100 generations).
Therefore, while we recognize that some populations of the
Alexander Archipelago wolf are small and insular (e.g., GMU 2
population), our review of the best available information does not
suggest that these characteristics currently are having a measurable
effect at the population or rangewide level. However, given that the
GMU 2 population is expected to decline by an average of 8 to 14
percent over the next 30 years, inbreeding depression and genetic
bottlenecking may be a concern for this population in the future, but
we think that possible future genetic consequences experienced by the
GMU 2 population will not have an effect on the taxon as a whole. Thus,
we conclude that small and isolated population effects do not
constitute a threat to the Alexander Archipelago wolf, nor are they
likely to become a threat in the future.
Hybridization With Dogs
We reviewed hybridization with domestic dogs as a potential
stressor to the Alexander Archipelago wolf. Based on microsatellite
analyses, Munoz-Fuentes et al. (2010, p. 547) found that at least one
hybridization event occurred in the mid-1980s on Vancouver Island,
where wolves were probably extinct at one point in time, but then
recolonized the island from the mainland. Although hybridization has
been documented and is more likely to occur when wolf abundance is
unusually low, most of the range of the Alexander Archipelago wolf is
remote and unpopulated by humans, reducing the risk of interactions
between wolves and domestic dogs. Therefore, we conclude that
hybridization with dogs does not rise to the level of a threat at the
population or rangewide level and is not likely to do so in the future.
Overexploitation of Salmon Runs
As suggested in the petition, we considered overexploitation of
salmon runs and disease transmission from farmed Atlantic salmon (Salmo
salar) in coastal British Columbia as a potential stressor to the
Alexander Archipelago wolf (Atlantic salmon are not farmed in
southeastern Alaska). The best available information does not indicate
that the status of salmon runs in coastal British Columbia is having an
effect on coastal wolves. First, Alexander Archipelago wolf populations
in coastal British Columbia are stable or slightly increasing,
suggesting that neither overexploitation of salmon runs nor disease
transmission from introduced salmon are impacting the wolf populations.
Second, in coastal British Columbia, only 0 to 16 percent of the
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diet of the Alexander Archipelago wolf is salmon (Darimont et al. 2004,
p. 1871; Darimont et al. 2009, p. 130). Given the opportunistic food
habits of the coastal wolf, we postulate that reduction or even near
loss of salmon as a food resource may impact individual wolves in some
years, but likely would not result in a population- or rangewide-level
effect. Further, our review of the best available information does not
suggest that this is happening or will happen, or that coastal wolves
are acquiring diseases associated with farmed salmon. Therefore, we
conclude that overexploitation of salmon runs and disease transmission
from farmed salmon do not constitute a threat to the Alexander
Archipelago wolf at the population or rangewide level and are not
likely to do so in the future.
Conservation Efforts To Reduce Other Natural or Manmade Factors
Affecting Its Continued Existence
We are not aware of any conservation efforts or other voluntary
actions that may help to reduce effects associated with small and
isolated populations, hybridation with dogs, overexploitation of salmon
runs, disease transmission from farmed salmon, or any other natural or
manmade that may be affecting the Alexander Archipelago wolf.
Summary of Factor E
We find that other natural or manmade factors are present within
the range of the Alexander Archipelago wolf, but that none of these
factors is having a population or rangewide effect on the Alexander
Archipelago wolf. We acknowledge that some populations of the coastal
wolf are small and partially isolated, and therefore are susceptible to
genetic problems, but we found no evidence that inbreeding or
bottlenecking has resulted in a population or rangewide impact to the
Alexander Archipelago wolf. In addition, even though some populations
are small in size, many populations of the Alexander Archipelago wolf
exist and are well distributed on the landscape, greatly reducing
impacts from any future catastrophic events to the rangewide
population. We also found that the likelihood of hybridation with dogs
is low and that any negative impacts associated with the status of
salmon in coastal British Columbia are unfounded at this time; neither
of these potential stressors is likely to affect the continued
persistence of the Alexander Archipelago wolf at the population or
rangewide level. Therefore, based on the best available information, we
conclude that other natural or manmade factors do not pose a threat to
the Alexander Archipelago wolf, nor are they likely to become threats
in the future.
Cumulative Effects From Factors A Through E
The Alexander Archipelago wolf is faced with numerous stressors
throughout its range, but none of these individually constitutes a
threat to the taxon as a whole now or in the future. However, more than
one stressor may act synergistically or compound with one another to
impact the Alexander Archipelago wolf at the population or rangewide
level. Some of the identified stressors described above have potential
to impact wolves directly (e.g., wolf harvest), while others can affect
wolves indirectly (e.g., reduction in ungulate prey availability as a
result of timber harvest); further, not all stressors are present or
equally present across the range of the Alexander Archipelago wolf.
In this section, we consider cumulative effects of the stressors
described in Factors A through E. If multiple factors are working
together to impact the Alexander Archipelago wolf negatively, the
cumulative effects should be manifested in measurable and consistent
demographic change at the population or species level. Therefore, for
most populations such as those in coastal British Columbia and in GMU
2, we relied on trend information to inform our assessment of
cumulative effects. For populations lacking trend information (e.g.,
GMUs 1, 3, and 5A), we examined the severity, frequency, and certainty
of stressors to those populations and relative to the populations for
which we have trend information to evaluate cumulative effects. We then
assess the populations collectively to draw conclusions about
cumulative effects that may be impacting the rangewide population.
In coastal British Columbia, Alexander Archipelago wolf populations
are stable or slightly increasing (see ``Abundance and Trend,'' above),
despite multiple stressors facing these populations at levels similar
to or greater than most populations in southeastern Alaska. The
stability of the wolf populations in coastal British Columbia over the
last 15 years suggests that cumulative effects of stressors such as
timber harvest, road development, and wolf harvest are not negatively
impacting these populations.
The GMU 2 population of the Alexander Archipelago wolf apparently
experienced a gradual decline between 1994 and 2013, and then declined
substantially between 2013 and 2014, although the overall decline is
not statistically significant owing to the large variance surrounding
the point estimates (see ``Abundance and Trend,'' above). Nonetheless,
we found evidence that timber harvest (Factor A) and wolf harvest
(Factor B) are impacting this population, and these two stressors
probably have collectively caused the apparent decline. Given
reductions in deer habitat capability as a result of extensive and
intensive timber harvest, we expect the GMU 2 wolf population to be
somewhat depressed and unable to sustain high rates of wolf harvest.
However, in our review of the best available information, we found that
high rates of unreported harvest are resulting in unsustainable total
harvest of Alexander Archipelago wolves in GMU 2 and that roads
constructed largely to support the timber industry are facilitating
unsustainable rates of total wolf harvest. Based on a population model
specific to GMU 2, Gilbert et al. (2015, p. 43) projected that the wolf
population will decline by another 8 to 14 percent, on average, over
the next 30 years, largely owing to compounding and residual effects of
logging, but also wolf harvest, which results in direct mortality and
has a more immediate impact on the population. These stressors and
others such as climate related events (i.e., snowfall) are interacting
with one another to impact the GMU 2 wolf population and are expected
to continue to do so in the future provided that circumstances remain
the same (e.g., high unreported harvest rates).
In the remainder of southeastern Alaska where the Alexander
Archipelago wolf occurs (i.e., GMUs 1, 3, and 5A), we lack trend and
projected population estimates to inform our assessment of cumulative
effects, and, therefore, we considered the intensity, frequency, and
certainty of stressors present. We found that generally the stressors
facing wolf populations in GMUs 1, 3, and 5A occur in slightly higher
intensity compared to populations in coastal British Columbia (Regions
5 and 6), but significantly lower intensity than the GMU 2 population.
In fact, the percent of logged forest and road densities are among the
lowest in the range of the Alexander Archipelago wolf. Although wolf
harvest rates were moderately high in GMUs 1, 3, and 5A, given the
circumstances of these populations, we found no evidence to suggest
that they were having a population-level effect. Importantly, our
review of the best available information did not suggest that
unreported harvest was occurring at high rates like in GMU 2, and
hunter
[[Page 453]]
and trapper access was comparatively lower (i.e., road density, ratio
of shoreline to land area). In addition, the populations in GMUs 1, 3,
and 5A are most similar biologically to the coastal British Columbian
populations; all of these wolf populations have access to a variety of
ungulate prey and are not restricted to deer, and none is as isolated
geographically as the GMU 2 population. We acknowledge that elements of
GMU 3 are similar to those in GMU 2 (e.g., island geography), but
ultimately we found that GMU 3 had more similarities to GMUs 1 and 5A
and coastal British Columbia.
Therefore, in considering all of the evidence collectively, we
presume that Alexander Archipelago wolf populations in GMUs 1, 3, and
5A likely are stable and are not being impacted by cumulative effects
of stressors because these populations face similar stressors as the
populations in coastal British Columbia, which are stable or slightly
increasing. The weight of the available information led us to make this
presumption regarding the Alexander Archipelago wolf in GMUs 1, 3, and
5A, and we found no information to suggest otherwise. We think our
reasoning is fair and supported by the best available information,
although we recognize the uncertainties associated with it.
In summary, we acknowledge that some of the stressors facing
Alexander Archipelago wolves interact with one another, particularly
timber harvest and wolf harvest, but we determined that all but one of
the wolf populations do not exhibit impacts from cumulative effects of
stressors. We found that about 62 percent of the rangewide population
of the Alexander Archipelago wolf is stable (all of coastal British
Columbia), and another 32 percent is presumed to be stable (GMUs 1, 3,
and 5A), suggesting that approximately 94 percent of the rangewide
population is not experiencing negative and cumulative effects from
stressors, despite their presence. Therefore, we conclude that
cumulative impacts of identified stressors do not rise to the level of
a threat to the Alexander Archipelago wolf and are unlikely to do so in
the future.
Finding
As required by the Act, we considered the five factors in assessing
whether the Alexander Archipelago wolf 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 Alexander Archipelago wolf. We reviewed the
petition, information available in our files, and other available
published and unpublished information, and we consulted with recognized
wolf experts and other Federal, State, and tribal agencies. We prepared
a Status Assessment that summarizes all of the best available science
related to the Alexander Archipelago wolf and had it peer reviewed by
three experts external to the Service and selected by a third-party
contractor. We also contracted the University of Alaska Fairbanks to
revise an existing population model for the GMU 2 wolf population,
convened a 2-day workshop with experts to review the model inputs and
structure, and had the final report reviewed by experts (Gilbert et al.
2015, entire). As part of our review, we brought together researchers
with experience and expertise in gray wolves and the temperate coastal
rainforest from across the Service to review and evaluate the best
available scientific and commercial information.
We examined a variety of potential threats facing the Alexander
Archipelago wolf and its habitats, including timber harvest, road
development, oil development, climate change, overexploitation,
disease, and effects associated with small and isolated populations. To
determine if these risk factors individually or collectively put the
taxon 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.
Throughout most of its range, the Alexander Archipelago wolf is
stable or slightly increasing or is presumed to be stable based on its
demonstrated high resiliency to the magnitude of stressors present. In
coastal British Columbia, which constitutes 67 percent of the range and
62 percent of the rangewide population, the Alexander Archipelago wolf
has been stable or slightly increasing over the last 15 years. In
mainland southeastern Alaska (GMUs 1 and 5A) and in GMU 3,
approximately 29 percent of the range and 32 percent of the rangewide
population, we determined that the circumstances of these wolf
populations were most similar to those in coastal British Columbia,
and, therefore, based on the best available information, we reasoned
that the Alexander Archipelago wolf likely is stable in GMUs 1, 3, and
5A. In GMU 2, which includes only 4 percent of the range and 6 percent
of the rangewide population, the Alexander Archipelago wolf has been
declining since 1994, and is expected to continue declining by another
8 to 14 percent, on average, over the next 30 years. Nonetheless, we
conclude that the Alexander Archipelago wolf is stable or slightly
increasing in nearly all of its range (96 percent), representing 94
percent of the rangewide population of the taxon.
We then identified and evaluated existing and potential stressors
to the Alexander Archipelago wolf. We aimed to determine if these
stressors are affecting the taxon as a whole 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 taxon, rangewide or at the
population level. Because the Alexander Archipelago wolf is broadly
distributed across its range and is a habitat and diet generalist, we
evaluated whether each identified stressor was expected to impact
wolves directly or indirectly and whether wolves would be resilient to
any impact.
We examined several stressors that are not affecting the Alexander
Archipelago wolf currently and are unlikely to occur at a magnitude and
frequency in the future that would result in a population- or
rangewide-level effect. We found that oil and gas development, disease,
predation, effects associated with small and isolated populations,
hybridization with domestic dogs, overexploitation of salmon runs, and
disease transmission from farmed salmon are not threats to the
Alexander Archipelago wolf (see discussions under Factors A, C, and E,
above). Most of these stressors are undocumented and speculative,
rarely occur, are spatially limited, or are not known to impact gray
wolves in areas of overlap. Although disease is known to affect
populations of gray wolves, we found few reports of disease in the
Alexander Archipelago wolf, and none resulted in mortality. Therefore,
based on the best available information, we conclude that none of these
stressors is having a population- or rangewide-level effect on the
Alexander Archipelago wolf, or is likely to do so in the foreseeable
future.
Within the range of the Alexander Archipelago wolf, changes in
climate are occurring and are predicted to continue, likely resulting
in improved conditions for wolves. Climate models for southeastern
Alaska and coastal British Columbia project that precipitation as snow
will decrease substantially in the future, which will improve winter
conditions for deer, the primary prey species of wolves. Although
severe winters likely will continue to occur and will affect deer
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populations, we expect them to occur less frequently. Therefore, based
on the best available information, we conclude that the effects of
climate change are not a threat to the Alexander Archipelago wolf, nor
are they likely to become a threat in the foreseeable future.
We reviewed timber harvest and associated road development as
stressors to the Alexander Archipelago wolf and found that they are not
affecting wolves directly, in large part because the wolf is a habitat
generalist. Although wolves used den sites farther from logged stands
and roads than unused sites, den site selection was more strongly
influenced by natural features on the landscape such as slope,
elevation, and proximity to freshwater. Further, we did not find
evidence indicating that denning near logged stands and roads resulted
in lower fitness of wolves. Thus, we conclude that timber harvest and
associated road development are not affecting wolves at the population
or rangewide levels by decreasing suitable denning habitat. We did not
identify any other potential direct impacts to wolves as a result of
timber harvest or road development, so next we examined potential
indirect effects, specifically reduction of deer habitat capability.
Although the Alexander Archipelago wolf is an opportunistic
predator that feeds on a variety of marine, intertidal, and terrestrial
species, ungulates compose at least half of the wolf's diet throughout
its range, and deer is the most widespread and abundant ungulate
available to wolves. Timber harvest has reduced deer habitat
capability, which in turn is predicted to reduce deer populations,
especially in areas that have been logged intensively. However, based
largely on the stability of wolf populations in coastal British
Columbia despite intensive timber harvest, we conclude that wolves are
resilient to changes in deer populations provided that they have other
ungulate prey species available to them. We found that nearly all of
the Alexander Archipelago wolves (94 percent of the rangewide
population) have access to alternate ungulate prey such as mountain
goat, moose, and elk, and, based on wolf diet, Alexander Archipelago
wolves are consuming these prey species in areas where they are
available. We identified only one Alexander Archipelago wolf population
as an exception.
In GMU 2, deer is the only ungulate species available to wolves,
and, therefore, wolves in this population have a more restricted
ungulate diet and likely are being affected by cascading effects of
timber harvest. Both deer and wolves are projected to decline in GMU 2
in the future, largely due to long-term reduction in deer habitat
capability. However, we find that the GMU 2 population contributes
little to the rangewide population because it constitutes only 4
percent of the range and 6 percent of the rangewide population, is
largely insular and geographically peripheral, and appears to function
as a sink population. Therefore, while we recognize that timber harvest
and associated road development has modified a considerable portion of
the range of the Alexander Archipelago wolf, and will continue to do
so, we find that the taxon as a whole is not being affected negatively,
in large part because the wolf is a habitat and diet generalist. Based
on the best available information, we conclude that timber harvest and
associated road development do not rise to the level of a threat to the
Alexander Archipelago wolf, and are not likely to do so in the future.
Throughout its range, the Alexander Archipelago wolf is harvested
for commercial and subsistence purposes, and, therefore, we examined
overutilization as a stressor at the population and rangewide levels.
In coastal British Columbia, we presume that wolf harvest is not having
an effect at the population level given that populations there are
stable or slightly increasing. This presumption is supported by the
comparatively low rates of reported wolf harvest in coastal British
Columbia, although reporting of harvest is required only in Regions 1
and 2, and, therefore, we considered these rates as minimum values.
Nonetheless, we found no information suggesting that wolf harvest in
coastal British Columbia is affecting wolves at the population level,
as evidenced by the stability of the populations.
Within southeastern Alaska, where reporting is required, rates of
reported harvest on average are similar across all populations (17 to
21 mean percent of population annually). However, in GMU 2, unreported
harvest can be a substantial component of total harvest (38 to 45
percent), resulting in high rates of total harvest in some years, which
likely has contributed to the apparent population decline in GMU 2.
Although unreported harvest probably occurs in other parts of
southeastern Alaska, our review of the best available information does
not indicate that it is occurring at the same high rate as documented
in GMU 2. Further, access by hunters and trappers is significantly
greater in GMU 2 compared to elsewhere (see discussion under Factor B,
above), and, therefore, we find that applying rates of unreported
harvest from GMU 2 to other wolf populations in southeastern Alaska is
not appropriate. Thus, based on the best available information, we
think that wolf harvest in most of southeastern Alaska (i.e., GMUs 1,
3, and 5A) is not affecting wolves at the population level, but that
total wolf harvest in GMU 2 likely has occurred, at least recently, at
unsustainable rates, largely due to high rates of unreported harvest,
and has contributed to or caused an apparent decline in the population.
However, for the same reasons described above, we determined that
negative population impacts in GMU 2 do not affect the rangewide
population significantly, and, therefore, we conclude that wolf harvest
is not having a rangewide-level effect. In conclusion, we find that
overutilization is not a threat to the Alexander Archipelago wolf, nor
is it likely to become a threat in the foreseeable future.
In summary, we found that the Alexander Archipelago wolf
experiences stressors throughout its range, but based on our
consideration of the best available scientific and commercial
information, we determined that the identified stressors, individually
or collectively, do not pose a threat to the taxon at the rangewide
level now or in the foreseeable future. We determined that many of the
life-history traits and behaviors of the Alexander Archipelago wolf,
such as its variable diet, lack of preferential use of habitats, and
high reproductive potential, increase its ability to persist in highly
modified habitats with numerous stressors. Only one population of the
Alexander Archipelago wolf has declined and likely will continue to
decline, but this population contributes little to the taxon as a
whole, and, therefore, while we acknowledge the vulnerability of this
population to stressors such as timber harvest and wolf harvest, we
find that its status does not affect the rangewide status
significantly. Further, we found that approximately 94 percent of the
rangewide population of the Alexander Archipelago wolf is stable or
increasing, or presumed with reasonable confidence to be stable.
Therefore, based on our review of the best available scientific and
commercial information pertaining to the five factors, we find that the
threats are not of sufficient imminence, intensity, or magnitude to
indicate that the Alexander Archipelago wolf is in danger of extinction
(endangered), or likely to become endangered within the foreseeable
future (threatened), throughout all of its range.
[[Page 455]]
Significant Portion of the Range
Under the Act and our implementing regulations, a species may
warrant listing if it is in danger of extinction or likely to become so
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 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.'' We published a final policy interpreting the
phrase ``significant portion of its range'' (SPR) (79 FR 37578, July 1,
2014). The final policy states that (1) if a species is found to be
endangered or threatened throughout a significant portion of its range,
the entire species is listed as an endangered or a threatened species,
respectively, and the Act's protections apply to all individuals of the
species wherever found; (2) a portion of the range of a species is
``significant'' if the species is not currently endangered or
threatened throughout all of its range, but the portion's contribution
to the viability of the species is so important that, without the
members in that portion, the species would be in danger of extinction,
or likely to become so in the foreseeable future, throughout all of its
range; (3) the range of a species is considered to be the general
geographical area within which that species can be found at the time
the Service or the National Marine Fisheries Service makes any
particular status determination; and (4) if a vertebrate species is
endangered or threatened throughout an SPR, and the population in that
significant portion is a valid DPS, we will list the DPS rather than
the entire taxonomic species or subspecies.
The SPR policy is applied to all status determinations, including
analyses for the purposes of making listing, delisting, and
reclassification determinations. The procedure for analyzing whether
any portion is an SPR is similar, regardless of the type of status
determination we are making. The first step in our analysis of the
status of a species is to determine its status throughout all of its
range. If we determine that the species is in danger of extinction, or
likely to become so in the foreseeable future, throughout all of its
range, we list the species as an endangered (or threatened) species and
no SPR analysis will be required. If the species is neither in danger
of extinction nor likely to become so throughout all of its range, we
determine whether the species is in danger of extinction or likely to
become so throughout a significant portion of its range. If it is, we
list the species as an endangered or a threatened species,
respectively; if it is not, we conclude that listing the species is not
warranted.
When we conduct an SPR analysis, we first identify any portions of
the species' range that warrant further consideration. 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 are not reasonably likely to be significant and
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 in those portions or likely
to become so within the foreseeable future. We emphasize that answering
these questions in the affirmative is not a determination that the
species is endangered or threatened throughout a significant portion of
its range; rather, it is a step in determining whether a more detailed
analysis of the issue is required. In practice, a key part of this
analysis is whether the threats are geographically concentrated in some
way. If the threats to the species are affecting it uniformly
throughout its range, no portion is likely to warrant further
consideration. Moreover, if any concentration of threats apply only to
portions of the range that clearly do not meet the biologically based
definition of ``significant'' (i.e., the loss of that portion clearly
would not be expected to increase the vulnerability to extinction of
the entire species), those portions will not warrant further
consideration.
If we identify any portions that may be both (1) significant and
(2) endangered or threatened, we engage in a more detailed analysis to
determine whether these standards are indeed met. The identification of
an SPR does not create a presumption, prejudgment, or other
determination as to whether the species in that identified SPR is
endangered or threatened. We must go through a separate analysis to
determine whether the species is endangered or threatened in the SPR.
To determine whether a species is endangered or threatened throughout
an SPR, we will use the same standards and methodology that we use to
determine if a species is endangered or threatened throughout its
range.
Depending on the biology of the species, its range, and the threats
it faces, it may be more efficient to address the ``significant''
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.''
We evaluated the current range of the Alexander Archipelago wolf to
determine if there is any apparent geographic concentration of
potential threats to the taxon. We examined potential threats from
timber harvest, oil and gas development, road development, climate
change, effects of small and isolated populations, hybridization with
dogs, overexploitation of salmon runs, disease transmission from farmed
salmon, overutilization, disease, and predation. We found that
potential threats are concentrated in GMU 2, where they are
substantially greater than in other portions of its range. We
considered adjacent parts of the range that are contained in GMUs 1 and
3, but, based on the best available information, we did not find any
concentrations of stressors in those parts that were similar in
magnitude and frequency to the potential threats in GMU 2. Therefore,
we then considered whether GMU 2 is ``significant'' based on the
Service's SPR policy, which states that a portion of its range is
``significant'' if the taxon is not currently endangered or threatened
throughout all of its range, but the portion's contribution to the
viability of the taxon is so important that, without the members in
that portion, the taxon would be in danger of extinction, or likely to
become so in the foreseeable future, throughout all of its range.
We reviewed population and rangewide metrics in relation to GMU 2
to estimate the numerical contribution of GMU 2 to the viability of the
Alexander Archipelago wolf. We determined that GMU 2 constitutes only 4
percent of the total range and 9 percent of the range below 1,312 ft
(400 m) in elevation where these wolves spend most of their time (see
``Space and Habitat Use,'' above). In addition, based on the most
current population estimate for GMU 2, which was assessed in 2014, we
estimated that only 6 percent of the rangewide population occupies GMU
2. Recognizing the apparent recent decline in the GMU 2 population (see
``Abundance and Trend,'' above), we then estimated that in 2013, the
GMU 2 population
[[Page 456]]
composed about 13 percent of the rangewide population. We expect wolf
abundance to fluctuate annually at the population and rangewide scales,
but generally in recent years, we find that the GMU 2 population
composes a somewhat small percentage of the rangewide population.
Therefore, we conclude that, numerically, the GMU 2 population
contributes little to the viability of the taxon as a whole given that
it composes a small percentage of the current rangewide population and
it occupies a small percentage of the range of the Alexander
Archipelago wolf.
We then considered the biological contribution of the GMU 2
population to the viability of the Alexander Archipelago wolf. We found
that given its insularity and peripheral geographic position compared
to the rest of the range, the GMU 2 population contributes even less
demographically and genetically than it does numerically. In fact, it
appears to function as a sink population with gene flow and dispersal
primarily occurring uni-directionally from other areas to GMU 2 (see
``Dispersal and Connectivity,'' above). Therefore, overall, we found
that GMU 2 represents a small percentage of the range and rangewide
population of the Alexander Archipelago wolf, it is insular and
geographically peripheral, and it appears to be functioning as a sink
population to the Alexander Archipelago wolf. We conclude that,
although potential threats are concentrated in GMU 2, this portion's
contribution to the viability of the taxon as a whole is not so
important that, without the members of GMU 2, the Alexander Archipelago
wolf would be in danger of extinction, or likely to become so in the
foreseeable future, throughout all of its range.
Our review of the best available scientific and commercial
information indicates that the Alexander Archipelago wolf 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
Alexander Archipelago wolf as an endangered or threatened species under
the Act is not warranted at this time.
Evaluation of the GMU 2 Population of the Alexander Archipelago Wolf as
a Distinct Population Segment
After determining that the Alexander Archipelago wolf is not
endangered or threatened throughout all or a significant portion of its
range and is not likely to become so in the foreseeable future, we then
evaluate whether or not the GMU 2 wolf population meets the definition
of a distinct population segment (DPS) under the Act, as requested in
the petition.
To interpret and implement the DPS provisions of the Act and
Congressional guidance, we, in conjunction with the National Marine
Fisheries Service, published the Policy Regarding the Recognition of
Distinct Vertebrate Population Segments (DPS policy) in the Federal
Register on February 7, 1996 (61 FR 4722). Under the DPS policy, two
basic elements are considered in the decision regarding the
establishment of a population of a vertebrate species as a possible
DPS. We must first determine whether the population qualifies as a DPS;
this requires a finding that the population is both: (1) Discrete in
relation to the remainder of the taxon to which it belongs; and (2)
biologically and ecologically significant to the taxon to which it
belongs. If the population meets the first two criteria under the DPS
policy, we then proceed to the third element in the process, which is
to evaluate the population segment's conservation status in relation to
the Act's standards for listing as an endangered or threatened species.
These three elements are applied similarly for additions to or removals
from the Federal Lists of Endangered and Threatened Wildlife and
Plants.
Discreteness
In accordance with our DPS policy, we detail our analysis of
whether a vertebrate population segment under consideration for listing
may qualify as a DPS. As described above, we first evaluate the
population segment's discreteness from the remainder of the taxon to
which it belongs. 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.
We found that the GMU 2 population is markedly separated as a
consequence of physical, physiological, ecological, or behavioral
factors from other populations of the Alexander Archipelago wolf. It
occupies a portion of the Alexander Archipelago within the range of
wolf that is physically separated from adjacent populations due to
comparatively long and swift water crossings and the fact that few
crossings are available to dispersing wolves. Although low levels of
movement between the GMU 2 population segment and other populations
likely occur (see ``Dispersal and Connectivity,'' above), the GMU 2
wolf population is largely insular and geographically peripheral to the
rest of the range of the Alexander Archipelago wolf; further, the
Service's DPS policy does not require absolute separation to be
considered discrete.
In addition, several studies have demonstrated that, based on
genetic assignment tests, the GMU 2 wolf population forms a distinct
genetic cluster when compared to other Alexander Archipelago wolves
(Weckworth et al. 2005, pp. 923, 926; Breed 2007, p. 21). Further,
estimates of the fixation index (FST, the relative
proportion of genetic variation explained by differences among
populations) are markedly higher between the GMU 2 population and all
other Alexander Archipelago wolf populations than comparisons between
other populations (e.g., Weckworth et al. 2005, p. 923; Cronin et al.
2015, p. 7). Collectively, these findings indicate genetic
discontinuity between wolves in GMU 2 and those in the rest of the
range of the Alexander Archipelago wolf. We review these studies and
others in more detail in the Status Assessment (Service 2015, ``Genetic
analyses'').
We found that the GMU 2 population of the Alexander Archipelago
wolf is markedly separated as a consequence of physical (geographic)
features and due to genetic divergence from other populations of the
taxon. Therefore, we conclude that it is discrete under the Service's
DPS policy.
Significance
If a population is considered discrete under one or more of the
conditions described in the Service's DPS policy, its biological and
ecological significance will be considered in light of Congressional
guidance that the authority to list DPSs be used ``sparingly'' while
encouraging the conservation of genetic diversity. In making this
determination, we consider available scientific evidence of the
discrete population segment's importance to the taxon to which it
belongs. As precise circumstances are likely to vary considerably from
case to case, the DPS policy does not describe all the classes of
information that might
[[Page 457]]
be used in determining the biological and ecological importance of a
discrete population. However, the DPS policy describes four possible
classes of information that provide evidence of a population segment's
biological and ecological importance to the taxon to which it belongs.
As specified in the DPS policy (61 FR 4722), this consideration of the
population segment's significance may include, but is not limited to,
the following:
(1) Persistence of the discrete population segment in an ecological
setting unusual or unique to the taxon;
(2) Evidence that loss of the discrete population segment would
result in a significant gap in the range of a taxon;
(3) Evidence that the discrete population segment represents the
only surviving natural occurrence of a taxon that may be more abundant
elsewhere as an introduced population outside its historical range; or
(4) Evidence that the discrete population segment differs markedly
from other populations of the taxon in its genetic characteristics.
Given our determination that the GMU 2 wolf population is discrete
under the Service's DPS policy, we now evaluate the biological and
ecological significance of the population relative to the taxon as a
whole. A discrete population segment is considered significant under
the DPS policy if it meets one of the four elements identified in the
policy under significance (described above), or otherwise can be
reasonably justified as being significant. Here, we evaluate the four
potential factors suggested by our DPS policy in evaluating
significance of the GMU 2 wolf population.
Persistence of the Discrete Population Segment in an Ecological Setting
Unusual or Unique to the Taxon
We find that the GMU 2 population does not persist in an ecological
setting that is unusual or unique to the Alexander Archipelago wolf. To
evaluate this element, we considered whether or not the habitats used
by Alexander Archipelago wolves in GMU 2 include unusual or unique
features that are not used by or available to the taxon elsewhere in
its range. We found that the Alexander Archipelago wolf is a habitat
generalist, using a variety of habitats on the landscape and selecting
only for those that occur below 1,312 ft (400 m) in elevation (see
``Space and Habitat Use,'' above). Throughout its range, habitats used
by and available to the Alexander Archipelago wolf are similar with
some variation from north to south and on the mainland and islands, but
we found no unique or unusual features specific to GMU 2 that were not
represented elsewhere in the range. Although karst is more prevalent in
GMU 2, we found no evidence indicating that wolves selectively use
karst; in addition, karst is present at low and high elevations in GMUs
1 and 3 (Carstensen 2007, p. 24).
The GMU 2 wolf population has a more restricted ungulate diet,
comprised only of deer, than other populations of the Alexander
Archipelago wolf (see ``Food Habits,'' above). However, given that the
coastal wolf is an opportunistic predator, feeding on intertidal,
marine, freshwater, and terrestrial species, we find that differences
in ungulate prey base are not ecologically unique or unusual. In
addition, Alexander Archipelago wolves feed on deer throughout their
range in equal or even higher proportions than wolves in GMU 2 (e.g.,
Szepanski et al. 1999, p. 331; Darimont et al. 2009, p. 130),
demonstrating that a diet based largely on deer is not unusual or
unique. Thus, compared to elsewhere in the range, we found nothing
unique or unusual about the diet or ecological setting of wolves in GMU
2. Further, we did not identify any morphological, physiological, or
behavioral characteristics of the GMU 2 wolf population that differ
from those of other Alexander Archipelago wolf populations, which may
have suggested a biological response to an unusual or unique ecological
setting. Therefore, we conclude that the GMU 2 wolf population does not
meet the definition of significance under this element, as outlined in
the Service's DPS policy.
Evidence That Loss of the Discrete Population Segment Would Result in a
Significant Gap in the Range of a Taxon
We find that loss of the GMU 2 population of the Alexander
Archipelago wolf, when considered in relation to the taxon as a whole,
would not result in a significant gap in the range of the taxon. It
constitutes only 6 percent of the current rangewide population, only 4
percent of the range, and only 9 percent of the range below 1,312 (400
m) in elevation where the Alexander Archipelago wolf selectively
occurs. In addition, the GMU 2 population is largely insular and
geographically peripheral to other populations, and appears to function
as a sink population (see ``Abundance and Trend'' and ``Dispersal and
Connectivity,'' above). For these reasons, we found that the
demographic and genetic contributions of the GMU 2 wolf population to
the rangewide population are low and that loss of this population would
have a minor effect on the rangewide population of the Alexander
Archipelago wolf. Also, although rates of immigration to GMU 2 likely
are low (see ``Dispersal and Connectivity,'' above), recolonization of
GMU 2 certainly is possible, especially given the condition of the
remainder of the rangewide population. Therefore, we conclude that the
GMU 2 wolf population does not meet the definition of significance
under this element, as outlined in the Service's DPS policy.
Evidence That the Discrete Population Segment Represents the Only
Surviving Natural Occurrence of a Taxon That May Be More Abundant
Elsewhere as an Introduced Population Outside Its Historical Range
The GMU 2 population does not represent the only surviving natural
occurrence of the Alexander Archipelago wolf throughout the range of
the taxon. Therefore, we conclude that the discrete population of the
Alexander Archipelago wolf in GMU 2 does not meet the significance
criterion of the DPS policy under this factor.
Evidence That the Discrete Population Segment Differs Markedly From
Other Populations of the Taxon in Its Genetic Characteristics
We find that the GMU 2 population does not differ markedly from
other Alexander Archipelago wolves in its genetic characteristics. As
noted above in Discreteness, the GMU 2 population exhibits genetic
discontinuities from other Alexander Archipelago wolves due to
differences in allele and haplotype frequencies. However, those
discontinuities are not indicative of rare or unique genetic
characterisics within the GMU 2 population that are significant to the
taxon. Rather, several studies indicate that the genetic diversity
within the GMU 2 population is a subset of the genetic diversity found
in other Alexander Archipelago wolves. For example, the GMU 2
population does not harbor unique haplotypes; only one haplotype was
found in the GMU 2 population, and it was found in other Alexander
Archipelago wolves including those from coastal British Columbia
(Weckworth et al. 2010, p. 367; Weckworth et al. 2011, p. 2). In
addition, the number and frequency of private alleles in the GMU 2
population is low compared to other Alexander Archipelago wolves (e.g.,
Breed 2007, p. 18). The lack of unique haplotypes and the low numbers
of private alleles both indicate that the GMU 2 population has not been
completely isolated historically from other Alexander Archipelago
wolves. Finally, these genetic studies demonstrate that wolves in GMU 2
exhibit low genetic diversity
[[Page 458]]
(as measured through allelic richness, heterozygosity, and haplotype
diversity) compared to other Alexander Archipelago wolves (Weckworth et
al. 2005, p. 919; Breed 2007, p. 17; Weckworth et al. 2010, p. 366;
Weckworth et al. 2011, p. 2).
Collectively, results of these studies suggest that the genetic
discontinuities observed in the GMU 2 population likely are the outcome
of restricted gene flow and a loss of genetic diversity through genetic
drift or founder effects. Therefore, although the GMU 2 population is
considered discrete under the Service's DPS policy based on the
available genetic data, it does not harbor genetic characteristics that
are rare or unique to the Alexander Archipelago wolf and its genetic
contribution to the taxon as a whole likely is minor. Moreover, while
we found no genetic studies that have assessed adaptive genetic
variation of the Alexander Archipelago wolf, the best available genetic
data do not indicate that the GMU 2 population harbors significant
adaptive variation, which is supported further by the fact that the GMU
2 population is not persisting in an unusual or unique ecological
setting. Therefore, we conclude that the GMU 2 population does not meet
the definition of significance under this element, as outlined in the
Service's DPS policy.
Summary of Significance
We determine, based on a review of the best available information,
that the GMU 2 population is not significant in relation to the
remainder of the taxon. Therefore, this population does not qualify as
a DPS under our 1996 DPS policy and is not a listable entity under the
Act. Because we found that the population did not meet the significance
element and, therefore, does not qualify as a DPS under the Service's
DPS policy, we will not proceed with an evaluation of the status of the
population under the Act.
Determination of Distinct Population Segment
Based on the best scientific and commercial information available,
as described above, we find that, under the Service's DPS policy, the
GMU 2 population is discrete, but is not significant to the taxon to
which it belongs. Because the GMU 2 population is not both discrete and
significant, it does not qualify as a DPS under the Act.
Conclusion of 12-Month Finding
Our review of the best available scientific and commercial
information indicates that the Alexander Archipelago wolf 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
Alexander Archipelago wolf 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 Alexander Archipelago wolf to our
Anchorage Fish and Wildlife Field Office (see ADDRESSES) whenever it
becomes available. New information will help us monitor the Alexander
Archipelago wolf and encourage its conservation. If an emergency
situation develops for the Alexander Archipelago wolf, we will act to
provide immediate protection.
References Cited
A complete list of references cited is available on the Internet at
http://www.regulations.gov and upon request from the Anchorage Fish and
Wildlife Field Office (see ADDRESSES).
Authors
The primary authors of this document are the staff members of the
Anchorage 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: December 15, 2015.
Stephen Guertin,
Acting Director, Fish and Wildlife Service.
[FR Doc. 2015-32473 Filed 1-5-16; 8:45 am]
BILLING CODE 4333-15-P