Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List the Red Knot Subspecies Calidris canutus roselaari as Endangered, 304-311 [2010-33187]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 76, Number 2 (Tuesday, January 4, 2011)]
[Proposed Rules]
[Pages 304-311]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-33187]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R7-ES-2010-0061; MO 92210-0-0008]


Endangered and Threatened Wildlife and Plants; 90-Day Finding on 
a Petition To List the Red Knot Subspecies Calidris canutus roselaari 
as Endangered

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of 90-day petition finding.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
90-day finding on a petition to list the roselaari subspecies of red 
knot (Calidris canutus roselaari) as endangered under the Endangered 
Species Act of 1973, as amended (Act). Based on our review, we find 
that the petition does not present substantial information indicating 
that listing this subspecies may be warranted. Therefore, we are not 
initiating a status review in response to this petition. However, we 
ask the public to submit to us any new information that becomes 
available concerning the status of, or threats to, C. c. roselaari or 
its habitat at any time.

DATES: The finding announced in this document was made on January 4, 
2011.

ADDRESSES: This finding is available on the Internet at https://www.regulations.gov at Docket Number FWS-R7-ES-2010-0061. Supporting 
documentation we used in preparing this finding is available for public 
inspection, by appointment, during normal business hours at the U.S. 
Fish and Wildlife Service, Fairbanks Fish and Wildlife Field Office, 
101 12th Avenue, Room 110, Fairbanks, AK 99701. Please submit any new 
information, materials, comments, or questions concerning this finding 
to the above street address.

FOR FURTHER INFORMATION CONTACT: Ted Swem, Branch Chief, Endangered 
Species Program of the Fairbanks Fish and Wildlife Field Office (see 
ADDRESSES); by telephone (907-456-0441); or by facsimile to (907-456-
0208). 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)(A) of the Act (16 U.S.C. 1531 et seq.) requires 
that we make a finding on whether a petition to list, delist, or 
reclassify a species presents ``substantial scientific or commercial 
information'' indicating that the petitioned action may be warranted. 
We base this finding on information provided in the petition, 
supporting information submitted with the petition, and information 
otherwise available in our files. To the maximum extent practicable, we 
make this finding within 90 days of our receipt of the petition, and 
publish our notice of the finding promptly in the Federal Register.
    Our standard for ``substantial scientific or commercial 
information'' is the ``amount of information that would lead a 
reasonable person to believe that the measure proposed in the petition 
may be warranted'' (50 CFR 424.14(b)). If we find that ``substantial 
scientific or commercial information'' was presented, we are required 
to promptly conduct a species status review, which we summarize in a 
subsequent finding due within 12 months.

Petition History and Previous Federal Action

    On February 27, 2008, we received a petition, dated February 27, 
2008, from Defenders of Wildlife, American Littoral Society, American 
Bird Conservancy, Delaware Audubon, Delaware Nature Society, Delaware 
Riverkeeper Network, National Audubon Society, New Jersey Audubon 
Society, and Citizens Campaign for the Environment, requesting that the 
Department of the Interior (Department) use its emergency authorities 
under section 4(b)(7) of the Act to list the red knot C. c. rufa 
subspecies as an endangered species. The petitioners also seek to have 
the Department list as endangered ``a broader taxon comprising both the 
rufa subspecies and the roselaari subspecies.'' The petition further 
calls for a ``national listing based on similarity of appearance'' 
under section 4(e) of the Act. The petition contains the requisite 
identification information for the petitioners, as required at 50 CFR 
424.14(a).
    We previously made a ``warranted but precluded'' determination (in 
response to one petition received on August 9, 2004, and two others 
received on August 5, 2005), on September 12, 2006, for the C. c. rufa 
subspecies and added this subspecies to our list of candidate species 
with a listing priority number of 6 (71 FR 53758-53759). ``Warranted 
but precluded'' means we have sufficient information on biological 
vulnerability and threats to support a proposal to list as endangered 
or threatened, but that preparation and publication of a listing 
proposal is precluded by higher priority listing actions. In a May 1, 
2008, letter responding to the current petition, we stated that while 
we had previously made a determination that listing C. c. rufa was 
``warranted but precluded'' and added the subspecies to our candidate 
list, we were re-evaluating--as part of our annual candidate review 
process--whether listing remained ``warranted but precluded'' and 
whether to utilize the emergency listing provisions of the Act. We also 
stated in our May 1, 2008, letter that, due to court orders and 
judicially approved settlement agreements for other listing and 
critical habitat determinations under the Act that required nearly all 
of our listing and critical habitat funding for fiscal year 2008, we 
would not be able to further address the petition's request to list C. 
c. roselaari at that time but would complete the action when workload 
and funding allowed. Subsequently, in the 2008 Candidate Notice of 
Review for C. c. rufa, the Service took into consideration the 
information supplied by the petitioners and changed the listing 
priority number from 6 to 3 for this subspecies because threats were 
determined to be imminent (73 FR 75178-75179, December 10, 2008). 
Because we determined that it was not necessary, the Service did not 
emergency list C. c. rufa, as set forth in the October 29, 2009, 
Species Assessment and Listing Priority Assignment Form for Calidris 
canutus rufa (Service 2009). In the 2009 Candidate Notice of Review for 
C. c.

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rufa, the Service retained a listing priority number of 3 for this 
subspecies (74 FR 57825-57826, November 9, 2009).
    Accordingly, as we addressed the petitioners' request for an 
emergency listing of the rufa subspecies in the October 29, 2009, 
Species Assessment and Listing Priority Assignment Form, this finding 
addresses only whether the petition presents substantial scientific or 
commercial information that the following petitioned actions may be 
warranted: (1) Listing the C. c. roselaari as endangered or threatened, 
(2) listing ``a broader taxon comprising both the rufa subspecies and 
the roselaari subspecies'' as endangered or threatened, and (3) a 
``national listing based on similarity of appearance'' under section 
4(e) of the Act. We base our determinations on information set forth in 
the petition, information in the Service's files, and other readily 
available information.

Species Information

    The red knot (Calidris canutus) is a medium-sized (23 to 28 
centimeters, or 9 to 11 inches, in length), Arctic-breeding shorebird 
within the genus Calidris. The breeding plumage of the red knot is 
distinctive; the face, breast, and upper belly are a rich rufous-red, 
and the lower belly and under tail-coverts are light-colored with dark 
flecks. Upperparts are dark brown with white and rufous feather edges; 
outer primary feathers are dark brown to black (Davis 1983, p. 372; 
Harrington 2001, p. 2). Females are similar to males in appearance, but 
rufous colors are typically less intense in females, with more buff or 
light gray coloration on dorsal parts (Niles et al. 2007, p. 14). 
Subtle subspecies differences in breeding plumage have been described. 
Non-breeding plumage, dusky gray above and whitish below, is similar 
between sexes and among subspecies (Harrington 2001, p. 2). Juveniles 
resemble non-breeding adults, except that the feathers of the scapulars 
and wing coverts of juveniles are edged with white and have narrow, 
dark subterminal bands, giving the upperparts a scalloped appearance 
(Davis 1983, p. 372); whereas the feathers of adults are more uniform. 
The black bill is long, straight, and slightly tapered, and the legs 
and feet are dark green or black (Davis 1983, p. 373). Adult body mass 
varies seasonally, with highest mean mass occurring during spring (205 
grams (g); 7.2 ounces (oz)) and fall (172 g; 6 oz) migration, and 
lowest values occurring during early winter (125 g; 4.4 oz) (Harrington 
2001, p. 12).
    Six subspecies of red knots (C. c. canutus, C. c. piersma, C. c. 
rogersi, C. c. rufa, C. c. roselaari, and C. c. islandica) are 
currently recognized worldwide based on small differences in body 
dimensions and breeding plumage characteristics, and discrete breeding 
areas and migration routes (Piersma and Baker 2000, p. 109; Niles et 
al. 2007, p. 3). In all subspecies, sexual dimorphism occurs in plumage 
coloration (Tomkovich 1992, p. 18), as well as both bill length and 
body weight, with females having longer bills and higher body weights 
on average than males (Niles et al. 2007, p. 7).
    Four genetically distinct groups of red knots were recently 
identified through genetic analysis; they are comprised of C. c. 
canutus, C. c. piersma, C. c. rogersi, and a North American group 
containing C. c. rufa, C. c. roselaari and C. c. islandica (Buehler and 
Baker 2005, p. 502). C. c. islandica breeds in the Canadian high Arctic 
and Greenland, and winters in western Europe. The other two subspecies 
in the North American group occur within the United States: C. c. rufa, 
currently a candidate species for listing, and C. c. roselaari, the 
focus of this 90-day finding.
    C. c. roselaari and C. c. rufa are paler by comparison (with C. c. 
rufa considered the palest) to the other subspecies and have a much 
longer average bill-length (Harrington 2001, p. 4; Niles et al. 2007, 
p. 7). C. c. roselaari is longer-winged than the other subspecies, but 
bill-length overlaps extensively (Harrington 2001, p. 5). In breeding 
plumage, C. c. roselaari's dorsal coloration is described as similar to 
that of C. c. canutus, but darker with slightly more variegated 
pattern. Ventral coloration is considered more similar to that of C. c. 
rufa than to that of C. c. rogersi, especially with respect to amount 
of white plumage on vent and lower belly (Harrington 2001, p. 5). 
However, as recently as 2007, red knot researchers acknowledged that 
``no one has adequately compared morphological variation in C. c. rufa 
and C. c. roselaari populations'' (Niles et al. 2007, p. 7). In 2006, 
individual C. c. roselaari caught and measured at a wintering site in 
Guerrero Negro, Baja, Mexico, had longer bill-lengths than males 
belonging to wintering populations known or thought to be C. c. rufa, 
suggesting C. c. roselaari are larger than C. c. rufa (Niles et al. 
2008, p. 3).
    Based on genetics, the red knot is thought to have recently 
survived a genetic bottleneck (resulting in reduced genetic 
variability), with subspecies groups estimated to have diverged very 
recently. The three subspecies comprising the North American group, 
including C. c. roselaari, are estimated to have diverged within the 
last 5,500 years (Buehler and Baker 2005, p. 505). We accept the 
characterization of C. c. roselaari as a subspecies because each 
currently recognized subspecies is believed to occupy separate breeding 
areas, in addition to having morphological and behavioral character 
differences. The Service and partners are currently investigating red 
knot genetics to better assess population structure of C. c. roselaari 
and rufa subspecies; results are expected within the next few years.
    More is known about the range and biology of C. c. rufa, than about 
C. c. roselaari. C. c. roselaari breeds in Alaska and on Wrangel 
Island, Russia (Tomkovich 1992, p. 22); whereas C. c. rufa breeds in 
the central Canadian Arctic (Harrington 2001, p. 4). C. c. roselaari is 
the only red knot subspecies known to nest in the United States. Its 
breeding range in northwest and northern Alaska is not well known, but 
includes the Seward Peninsula and inland areas north of Kotzebue, 
including the DeLong Mountains of the Brooks Range (Childs 1969, p. 33; 
Kessel 1989, pp. 161-162; Kessel and Gibson 1978, p. 39; Harrington 
2001, p. 3).
    C. c. rufa migrates primarily along the Atlantic coast of North 
America, with most wintering sites along the coasts of South America 
and fewer wintering sites along the Atlantic and Gulf coasts of the 
southeastern United States (Harrington 2001, p. 4; Morrison et al. 
2006, pp. 76-77). Although red knots are known to use the Texas and 
Florida coasts, other extensive marsh areas of Gulf coast States have 
not been surveyed. There are sporadic reports of red knots in these 
areas, but the level of use is not known (A. Scherer, U.S. Fish and 
Wildlife Service, pers. comm. 2010). There has been taxonomic 
uncertainty regarding C. canutus wintering in the southeastern United 
States because C. canutus that winter in Florida, Georgia, and South 
Carolina have a different molt schedule and do not migrate to southern 
South America. These birds have been referred to in the past as either 
C. c. roselaari or C. c. rufa (Niles et al. 2007, pp. 9-10). However, 
in the attachment to the petition, Niles et al. (2008, p. 1) identify 
recent information that indicates C. c. roselaari is largely or wholly 
confined to the Pacific coast of the Americas during migration and in 
winter, and Niles et al. (2008, p. 1) conclude that red knot 
populations found along the western Atlantic Ocean coast (wintering in 
Florida, Brazil, and Tierra del Fuego) are C. c. rufa. The conclusion 
is based

[[Page 306]]

on banding records confirming that red knots found on the Pacific coast 
of North America breed in Alaska and Wrangel Island, Russia, and 
morphological measurements of wintering red knots captured in Baja, 
Mexico, indicating these birds were larger than red knots at other 
wintering sites where it was previously unclear if the birds were C. c. 
roselaari or C. c. rufa (Niles et al. 2008, p. 3).
    Currently, C. c. roselaari primarily use a few stopover sites 
during their northward migration to breeding areas in northern Alaska 
and Wrangel Island, Russia. The most important stopover sites are Grays 
Harbor and Willapa Bay in Washington, and Yukon-Kuskokwim Delta and 
Copper River Delta in Alaska (Isleib 1979, p. 128; Gill and Handel 
1990, p. 712; Page et al. 1999, p. 467). Smaller numbers have been 
documented during migration in the Yakutat Forelands, Alaska, and the 
San Francisco Bay, California, and during both migration and wintering 
along the southern coast of California (Andres and Browne 1998, p. 328; 
Page et al. 1999, p. 468; Stenzel et al. 2002, p. 75). The subspecies 
primarily bypasses Oregon and British Columbia (McGie 2003, p. 232; 
Buchanan 2007, p. 65). Use of stopover sites during fall migration is 
unclear, as the migration is protracted and large concentrations are 
not reported in fall at sites used during spring (Harrington 2001, p. 
7). Red knots are known to undertake long flights during migration that 
may span thousands of miles (Harrington 2001, p. 1); thus during fall 
migration they may bypass sites used in spring. Important wintering 
aggregations of C. c. roselaari have been documented in Western Mexico 
at Guerrero Negro, Baja California Sur (Carmona et al. 2008, p. 10), 
and along the Pacific Northwest coast of Mexico in the Gulf of 
California at Ensenada Pabellones and Bahia Santa Maria, Sinaloa 
(Engilis et al. 1998, p. 338). C. c. roselaari probably also winters 
farther south than Mexico (Niles et al. 2007, p. 20), but important 
sites have not been identified. We lack information on the historical 
range of C. c. roselaari.
    Different habitats are used by red knots for breeding and 
migration/wintering. During migration stopovers and in wintering areas, 
red knots are primarily found in coastal habitats, particularly in 
areas with extensive sandy intertidal flats or near tidal inlets or 
mouths of bays and estuaries (Harrington 2001, pp. 8-9). Prey items for 
C. c. roselaari include bivalves and other benthic invertebrates 
(Harrington 2001, p. 9).
    On the breeding grounds in Alaska, C. c. roselaari are widely 
dispersed inland near the Arctic coast (Harrington 2001, pp. 5, 8). 
Nesting has been documented in upland habitat, particularly on 
limestone mounds on windswept slopes, 42 to 48 kilometers (20 to 30 
miles) inland (Kessel 1989, p. 162; Harrington 2001, p. 8). The red 
knot's diet on the breeding grounds consists primarily of terrestrial 
invertebrates, but early in the breeding season they may consume a 
substantial amount of plant material, such as grass shoots and seeds 
(Kessel 1989, pp. 162-163; Harrington 2001, p. 11). Red knots lay one 
clutch (usually 4 eggs) per season. No information is available on 
hatching success or chick survival rates. Male parents brood and defend 
their young, which leave the nest within 24 hours of hatching 
(Harrington 2001, p. 20; Niles et al. 2007, pp. 28, 31-32). While the 
oldest wild red knot recorded worldwide was estimated to be 25 years 
old, few red knots are assumed to live more than 7 years (Niles et al. 
2007, p. 33).
    The historical and current population sizes of C. c. roselaari are 
uncertain, and the trend is unknown. Supporting documentation submitted 
with the petition acknowledges that all attempts to assess the 
population size of C. c. roselaari have been confounded by uncertainty 
as to which passage (migrating) or wintering population belongs to 
which subspecies (Niles et al. 2008, p. 2). Although C. c. roselaari is 
now considered to be largely or wholly confined to the Pacific coast of 
the Americas during migration and in winter (Niles et al. 2008, p. 1), 
limited data exist from the sites along the Pacific coast of North 
America that are known to be used by this subspecies; in addition, the 
complete extent of wintering locations and the numbers breeding in 
Alaska are unknown. Population estimates have ranged from 150,000 
(Brown et al. 2001, p. 53; Morrison et al. 2001, p. 34) to 20,000 
(Morrison et al. 2006, p. 75) with inclusion of red knot populations 
found along the western Atlantic Ocean coast (now considered to be C. 
c. rufa), to less than 10,000 when including only the Pacific coast of 
the North America population (Niles et al. 2008, p. 6).
    The longest-running data set comes from counts on the central 
Yukon-Kuskokwim Delta at three field sites where C. c. roselaari are 
commonly observed during spring migration. While a peak daily count of 
110,000 red knots was observed in 1980 at Tutakoke River (Gill and 
Handel 1990, p. 712), peak daily count has not exceeded 6,380 (Service, 
unpublished data) in all other years before and after 1980 (24 of 31 
years with peak count data from 1978-2007). There is no evidence of a 
long-term decline based on the one anomalous count in 1980. Overall, 
observed peak numbers have varied substantially among years (range 25--
6,380 without 1980 count); the observed variation is unexplained, and 
no trend is detectable. The reported counts are conducted on a small 
portion of coastal Yukon-Kuskokwim Delta. More extensive mudflats occur 
outside of the study area; thus, while unknown, it is possible C. c. 
roselaari also occupies these areas to varying degrees during spring 
migration, which could account for the observed variation in numbers 
among years. We consider the numbers reported from counts on the Yukon-
Kuskokwim Delta to represent minimum numbers passing through the entire 
delta, with recent observations indicating a minimum, but not absolute 
number, of less than 10,000 individuals. On the Copper River Delta, 
Alaska, count-based estimates increased from 10,000 in the 1960s to 
40,000-50,000 in the early 1970s, to as high as 100,000 in late 1970s 
(Isleib 1979, p. 128). None of the data collected at either the Yukon-
Kuskokwim or Copper River Deltas included systematic or replicate 
counts, evaluation of accuracy, or assessment of turnover rates, which 
would be needed to determine actual abundance from the counts. We also 
do not know whether or not birds stopping at the Copper River Delta 
also stop at the Yukon-Kuskokwim Delta or migrate directly to the 
breeding grounds and therefore represent additional individuals. 
Supporting documentation submitted with the petition (Niles et al. 
2008, p. 6) claims that C. c. roselaari might have declined from 
greater than 100,000 (in period 1975-1980) to less than 10,000, if the 
large numbers reported in Alaska in 1975-1980 were all individuals of 
this subspecies. However, it has been suggested (Morrison et al. 2006, 
p. 76) and noted in the supporting documentation to the petition (Niles 
et al. 2008, p. 5), that some of the birds seen during the high-count 
years might have been due to an unusual arrival of C. c. rogersi, which 
breed in eastern Siberia and resemble C. c. roselaari in appearance 
(Morrison et al. 2006, p. 34). Alternatively, inter-annual variation in 
movements and migration routes through Alaska may have caused large 
variation in the proportion of C. c. roselaari that are subject to 
counting among years. Thus, these exceptionally large counts are 
difficult to interpret, and cannot with reliability be ascribed

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to C. c. roselaari, or used to infer trends in abundance of C. c. 
roselaari.
    Data from sites outside Alaska are fragmentary and difficult to 
interpret, particularly given that counts at some sites have fluctuated 
among years, presumably due to changing environmental conditions. The 
petition (p. 4) states that the current C. c. roselaari population 
totals fewer than 10,000 individuals with uncertainty regarding the 
extent of the subspecies' decline. While it is possible that the 
population size is less than 10,000, observations have not been 
collected in a long enough time-series at any of these sites to 
determine population trend at particular sites or to accurately 
estimate overall population size. The Service is currently 
collaborating with shorebird researchers to estimate the abundance of 
the stopover population of C. c. roselaari in important Pacific Flyway 
stopover areas in Washington (Grays Harbor and Willapa Bay) as a means 
of determining if a reliable estimate of the population size of this 
subspecies can be developed (Brad Andres, Service, pers. comm. 2010).
    C. c. roselaari is currently listed as a Bird of Conservation 
Concern by the U.S. Fish and Wildlife Service, Division of Migratory 
Bird Management (USFWS 2008, p. 66), which deems it a priority species 
for conservation actions. This list is based on an assessment score 
from three bird conservation plans: Partners in Flight North American 
Landbird Conservation Plan, United States Shorebird Conservation Plan, 
and North American Waterbird Conservation Plan (USFWS 2008, p. 2). 
While this list provides no regulatory protection, its purpose is to 
provide a conservation benefit by drawing attention to the subspecies' 
needs.

Evaluation of Information for This Finding

Request To List C. c. roselaari

    In making this 90-day finding, we first evaluated whether 
information regarding the threats to C. c. roselaari, as presented in 
the petition and other information available in our files, is 
substantial, thereby indicating that the petitioned action of listing 
the roselaari subspecies may be warranted. Section 4 of the Act (16 
U.S.C. 1533) and its implementing regulations at 50 CFR part 424 set 
forth the procedures for adding a species to, or removing a species 
from, the Federal Lists of Endangered and Threatened Wildlife and 
Plants. A species may be determined to be an endangered or threatened 
species due to one or more of the five factors described in section 
4(a)(1) of the Act:
    (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 considering what factors might constitute threats to a species, 
we must look beyond the exposure of the species to the factor to 
evaluate whether the species may respond to the factor in a way that 
causes actual or likely impacts to the species. If there is exposure to 
a factor and the species responds negatively, the factor may be a 
threat and we attempt to determine how significant a threat it is. The 
threat may be significant if it drives, or contributes to, the risk of 
extinction of the species such that the situation may warrant listing 
the species as endangered or threatened as those terms are defined in 
the Act. The identification of factors that could impact a species 
negatively may not be sufficient to compel a finding that substantial 
information has been presented suggesting that listing may be 
warranted. The information should contain evidence or the reasonable 
extrapolation that these factors may be operative threats that act on 
the species to the point that the species may meet the definition of 
threatened or endangered under the Act. We found no information to 
suggest that threats may be acting on, or are likely to act on, C. c. 
roselaari such that the subspecies may become in danger of extinction 
now or in the foreseeable future.
    In making this 90-day finding, we evaluated whether there is 
substantial information regarding the threats to C. c. roselaari 
presented in the petition and other information available in our files 
indicating that the petitioned action of listing C. c. roselaari may be 
warranted. Our evaluation of this information is presented below.

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

    Supporting documentation submitted with the petition asserts that, 
as a small population, C. c. roselaari is particularly vulnerable to 
habitat loss (Niles et al. 2008, p. 11), but that documentation does 
not support this statement with any evidence that this factor is 
impacting or is likely to impact this subspecies.
    The primary factor threatening C. c. rufa is destruction and 
modification of its habitat, particularly the modification of habitat 
in Delaware Bay through harvesting of horseshoe crabs (74 FR 57825, 
November 9, 2009). During spring migration, one of the key stopover 
sites for C. c. rufa is Delaware Bay, where they forage on horseshoe 
crab (Limulus polyphemus) eggs to replenish resources needed to 
complete their migration (Harrington 2001, p. 11). As the C. c. 
roselaari is now considered to be confined to the Pacific coast, this 
subspecies is presumably not subjected to threats associated with 
habitat loss in Delaware Bay or at other sites used by C. c. rufa along 
the Atlantic coast.
    Because the extent of C. c. roselaari's historical and current 
range is unknown, it is challenging to assess the extent of historical 
habitat loss that has occurred and its impact on this subspecies. We 
believe, however, that little habitat loss has occurred on the breeding 
grounds or key migration sites used by C. c. roselaari in Alaska, due 
to the areas' remoteness. But wetland loss has occurred throughout the 
United States due to development (Dahl 2006, p. 15). We, therefore, 
assume some direct loss of habitat due to development has occurred at 
migration stopover sites for C. c. roselaari along the Pacific coast of 
the United States. We have no evidence in our files, however, on the 
extent of this loss or information suggesting that this habitat loss 
has resulted in a decline of this subspecies.
    Wetland habitat loss has also occurred along the Pacific coast of 
the United States due to the spread of invasive plant species, 
including wetland habitat loss at key migration stopover sites used by 
C. c. roselaari. In particular, nonnative cordgrass (Spartina) species 
are aggressive weeds that disrupt ecosystems of native saltwater 
estuaries by outcompeting native vegetation and converting mudflats 
into monotypic Spartina meadows that accumulate sediment (Phillips et 
al. 2008, p. 5). This results in decreased plant diversity, elevated 
intertidal areas, and displacement of invertebrates, all of which 
reduce useable foraging and roosting habitat for shorebirds (Phillips 
et al. 2008, p. 5).
    During the 1990s, the spread of Spartina completely covered some 
key spring stopover sites for C. c. roselaari in Willapa Bay and 
portions of Grays Harbor, Washington (Buchanan 2003, pp. 47-48; 
Chappell 2005, p. 153; Buchanan 2006, p. 65). Eradication efforts have 
been under way in Washington, as well as in other locations along the 
Pacific coast, including San Francisco Bay, California. Since 2004, the 
Service has cooperated

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with Washington and other groups in a Statewide effort to eradicate 
Spartina from the State's marine waters. This effort has been extremely 
successful, with an 85 percent reduction in the number of solid acres 
of Spartina Statewide by 2007 (Phillips et al. 2008, p. 1).
    Spartina was considered to have been largely removed from important 
red knot habitat in Willapa Bay by 2006 (Buchanan 2006, p. 65). Control 
of Spartina meadows has resulted in increased use by shorebirds. Over 
time, this increased use occurs as the meadows return to pre-invasion 
natural mudflats with invertebrate prey for shorebirds (Phillips et al. 
2008, pp. 9-10). Spartina eradication efforts continue, followed by 
maintenance efforts within 3 to 5 years. Various eradication and 
control efforts have been underway for other invasive wetland plant 
species, such as the common reed (Phragmites australis). Other wetland 
restoration efforts include Service awards of 2010 National Coastal 
Wetland Conservation grants to Washington to acquire, restore, or 
enhance coastal wetlands, including acquisition and protection of 
wetland habitat in Grays Harbor and Willapa Bay. Thus, we determine 
that efforts to manage habitat loss in coastal migratory routes along 
the West Coast have likely ameliorated potential impacts, and the 
petition has not presented substantial information indicating that 
habitat loss may have affected the abundance or status of C. c. 
roselaari.
    Future sea-level rise and shoreline erosion may reduce the 
availability of intertidal habitat used by C. c. roselaari during 
migration or wintering. If habitat is limited, this could affect the 
subspecies' ability to build up adequate nutrient and energy stores to 
complete their long migrations (Meltofte et al. 2007, p. 36). The 
actual rates of sea-level rise are hard to predict with any 
reliability. However, sea-level rise is predicted to increase, and sea 
levels will likely rise globally by at least 0.18-0.59 meters (0.6--1.9 
feet) by the end of this century (IPCC 2007, p. 8). Site-specific rates 
will differ from the global mean; thus, the persistence of coastal and 
wetland environments for C. c. roselaari will depend on the degree to 
which sedimentation keeps pace with sea level rise, as well as local 
geomorphologic and other anthropogenic factors that affect wetlands at 
key migration and wintering sites.
    Galbraith et al. (2002, pp. 177-178) examined several different 
scenarios of future sea-level rise and projected the amount of 
intertidal habitat loss at key shorebird sites in the United States, 
including Willapa Bay and San Francisco Bay. Willapa Bay is predicted 
to lose a relatively small amount (8 percent) of its shorebird 
intertidal feeding habitats by 2050 but a larger amount (18 percent) by 
2100. San Francisco Bay is predicted to lose 12 percent of its 
intertidal feeding habitats in the northern bay and 24 percent in the 
southern bay by 2050, and 39 percent in the northern bay and 70 percent 
in the southern bay by 2100 under the 50-percent probability scenario 
(Galbraith et al. 2002, pp. 177-178). Such modeling efforts indicate 
that loss of intertidal habitat is expected to occur as sea levels rise 
at some sites currently used by C. c. roselaari. In other areas along 
C. c. roselaari's migration route that currently are, or could be, used 
by the subspecies, however, there may be a net gain of intertidal flats 
as coastline migrates inland. The Service is currently participating in 
multiple efforts to model impacts of future sea-level rise along the 
Pacific coast. When completed, these models may allow us to predict 
changes in habitat for C. c. roselaari, but at present we lack 
sufficient information to evaluate all sites used by the subspecies 
during migration and wintering to determine the scope and scale of 
potential habitat loss due to sea-level rise. We determine that at this 
time there is inadequate information to support the petitioners' 
contention that sea-level rise may pose a population-level threat to C. 
c. roselaari.
    While there appears to be ongoing and threatened habitat 
destruction and modification in areas used by migrating red knots along 
the Pacific coast in the United States and possibly in wintering 
habitats in Mexico and other unknown locations, the information 
presented or readily available does not suggest a population-level 
impact to C. c. roselaari from habitat loss in these areas. In summary, 
we find that the information provided in the petition, as well as other 
information in our files, does not present ``substantial scientific or 
commercial information'' indicating that the petitioned action of 
listing the roselaari subspecies may be warranted due to the present or 
threatened destruction, modification, or curtailment of its habitat or 
range.

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

    The petition does not claim that overutilization of C. c. roselaari 
for commercial, recreational, scientific, or educational purposes is 
taking place or will take place, and does not provide any evidence that 
this factor may be impacting or will likely impact the subspecies. In 
the second half of the 19th and first quarter of 20th centuries, red 
knots were heavily hunted for both market and sport (Harrington 2001, 
p. 22). Hunting of red knots is no longer allowed in the United States. 
Based on band recoveries, red knots are hunted in some regions of South 
America. Take has been documented in Guianas and Barbados (Harrington 
2001, p. 22), areas likely occupied by C. c. rufa. The level of hunting 
and impact to C. c. roselaari is unknown. The available information 
does not suggest that hunting poses, or is likely to pose, a 
significant threat to the subspecies. In summary, we find that the 
information provided in the petition, as well as other information in 
our files, does not present substantial scientific or commercial 
information indicating that the petitioned action of listing the 
roselaari subspecies may be warranted due to overutilization for 
commercial, recreational, scientific, or education purposes.

C. Disease or Predation

    The petition does not claim or provide any evidence that disease or 
predation of C. c. roselaari is a factor impacting or that will impact 
the subspecies. Although there is some information in our files that 
disease has been a cause of mortality for individuals of C. c. rufa, 
the Service has determined that disease and predation do not appear to 
pose threats to the persistence of C. c. rufa (USFWS 2009, pp. 23-24). 
We do not have any specific information regarding disease for C. c. 
roselaari. We have no information that predation rates have risen in 
recent years or been significantly affected by anthropogenic factors. 
On the breeding grounds, microtine rodent (lemming and vole) cycles 
affect shorebird nest predator cycles, resulting in year-to-year 
fluctuations in productivity (Niles et al. 2007, p. 161). The available 
evidence does not indicate that predation during the breeding season is 
having, or is likely to have, a long-term or significant impact on red 
knots (USFWS 2009, p. 23). In summary, we find that the information 
provided in the petition, as well as other information in our files, 
does not present ``substantial scientific or commercial information'' 
indicating that the petitioned action of listing the roselaari 
subspecies may be warranted due to disease or predation.

D. The Inadequacy of Existing Regulatory Mechanisms

    The petition does not claim that inadequacy of existing regulatory 
mechanisms for C. c. roselaari is taking

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place or is likely to take place, and does not provide any evidence 
that the lack of existing regulatory mechanisms is impacting or is 
likely to impact the subspecies.
    The petition does claim that existing regulatory mechanisms are 
inadequate to conserve foraging habitat on Delaware Bay for red knots 
foraging on horseshoe crabs at this key spring migration stopover site 
(Petition, p. 3). The Service has identified the inadequacy of existing 
regulatory mechanisms related to habitat destruction and modification, 
particularly in Delaware Bay, as a significant threat to C. c. rufa 
(USFWS 2009, p. 34). However, as C. c. roselaari is believed to be 
largely or wholly confined to the Pacific coast of the Americas during 
migration and in winter (Niles et al. 2008, p. 1), there is no evidence 
that this subspecies passes through Delaware Bay. Therefore, C. c. 
roselaari is presumably not affected by changes to habitat caused by 
inadequate regulatory mechanisms at Delaware Bay.
    The Migratory Bird Treaty Act (16 U.S.C. 703-712) (MBTA) is the 
only current Federal protection provided for C. c. roselaari. The MBTA 
prohibits ``take'' of individuals but, other than for nesting sites, 
provides no authority for protection of habitat or food resources. 
Niles et al. (1997, p. 165) report human disturbance as a major threat 
to C. c. rufa throughout its migratory range in the United States. The 
MBTA does not afford red knots protection from human disturbance on 
migratory and wintering areas. We believe that human disturbance to C. 
c. roselaari on their breeding grounds is minimal, due to the 
remoteness of these areas in Alaska and on Wrangel Island, Russia. We 
also believe limited human disturbance occurs at migration sites in 
Alaska, again due to the remote nature of these sites. Human 
disturbance, such as recreational use of beaches, including foraging 
and roosting sites, likely occurs on migratory areas along the Pacific 
coast of the United States and in wintering areas in Mexico and in 
other unknown locations, but we lack information in our files on the 
extent of disturbance and, if it is occurring, on the level of impact 
to the subspecies.
    In April 2007, the Committee on the Status of Endangered Wildlife 
in Canada determined that the C. c. roselaari type was threatened 
(COSEWIC 2007, p. 42). As a result, it is now protected under Canada's 
Federal Species at Risk Act (SARA). The designated unit (referred to as 
``C. c. roselaari type'') is defined to include ``the subspecies 
roselaari and two other populations that winter in Florida and northern 
Brazil and that seem to share characteristics of roselaari'' (COSEWIC 
2007, p. 43). These two populations wintering in Florida and northern 
Brazil are now considered to be C. c. rufa (Niles et al. 2008, p. 1), 
and the declines and threats identified for listing these two 
populations are confined to C. c. rufa. The SARA covers migratory birds 
in Canada on private, provincial, territorial, and Federal lands. Under 
SARA, projects that require an environmental assessment must consider 
the project's effects on listed wildlife species, including 
recommendations for measures to avoid or reduce adverse effects and 
plans to monitor the impacts of the project. Destruction of critical 
habitat of endangered and threatened species found on Federal lands is 
prohibited. The SARA has permit issuance criteria that include 
minimizing impacts of the proposed activity and avoiding jeopardy to 
the species.
    In summary, we find that the information provided in the petition, 
as well as other information in our files, does not present 
``substantial scientific or commercial information'' indicating that 
the petitioned action of listing the C. c. roselaari subspecies may be 
warranted due to inadequacy of existing regulatory mechanisms.

E. Other Natural or Manmade Factors Affecting Its Continued Existence

    The petition and its supporting documentation claim that new 
evidence suggests that C. c. roselaari is vulnerable to sudden and 
imminent extinction due to the inability of a suggested small 
population size to withstand catastrophic, population-altering events 
and harmful genetic mutation (Niles et al. 2008, p. 11; Petition, pp. 
4-5). However, the petition materials do not support this statement 
with any evidence that this factor is currently impacting or is likely 
to impact this subspecies in the foreseeable future. Small populations 
are generally at greater risk of extinction from stochastic processes 
than are large populations. However, a given population size will not 
carry with it the same risk for all species, and the fact that a 
species has low numbers does not necessarily indicate that it may be in 
danger of extinction in the foreseeable future. Although there is 
uncertainty about the population size of C. c. roselaari, a population 
with possibly fewer than 10,000 individuals, we do not have information 
in our files on vulnerability of the subspecies to stochastic events in 
the foreseeable future, nor did the petitioners provide any information 
regarding this. Consequently, in the absence of information identifying 
threats to the species and linking those threats to the rarity of the 
species, the Service does not consider rarity alone to be a threat.
    The petition also asserts that the 2006 and 2007 Candidate Notices 
of Review for C. c. rufa failed to discuss impacts of climate change to 
shorebirds or account for the potential destruction of habitat due to 
sea-level rise and other factors. The petition also asserts that the 
Service must consider these factors in its analysis (Petition, p. 4). 
However, the petition does not claim or provide any evidence that 
climate change is currently impacting, or is likely to impact, C. c. 
roselaari (Petition, pp. 4-5) in the foreseeable future. Sea-level rise 
is addressed above under Factor A.
    Besides sea-level rise, climate change could impact red knots as a 
consequence of the alteration of weather patterns, resulting in changes 
to habitat and environmental conditions, such as drying (and therefore 
potential loss) of breeding or intertidal habitat or alteration in prey 
availability. As an arctic nesting shorebird, C. c. roselaari is 
adapted to highly variable annual conditions on the breeding grounds 
(Meltofte et al. 2007, p. 11). In the short term, climatic amelioration 
could benefit Arctic shorebirds because earlier snowmelt and warmer 
summers increase both survival and productivity, for example by 
providing more food resources for adults and chicks on breeding grounds 
(Meltofte et al. 2007, p. 7). In the long term, habitat changes to both 
breeding and non-breeding areas could affect the subspecies negatively, 
but it is currently unknown to what extent shorebirds are able to adapt 
to rapidly changing climatic conditions (Meltofte et al. 2007, p. 34). 
In Alaska, C. c. roselaari currently nests in upland tundra habitat, 
which is drier than the Arctic coastal plain; thus, new habitat could 
become available on the Arctic coastal plain for this subspecies as 
habitat is lost in montane habitats. Weather variations are a natural 
occurrence and normally are not considered to be a threat to the 
persistence of a species unless the number of individuals is reduced to 
a very low level and the individuals are concentrated in an area that 
is subject to weather conditions that are likely to result in mortality 
or poor productivity or both (USFWS 2009, p. 30). While we expect 
climate change to continue into the future, and there could be a number 
of different types of effects on C. c. roselaari from climate change, 
the available information does not suggest that impacts from climate 
change are likely to result in population-level effects negatively 
impacting the subspecies. The petition does not

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present substantial information, nor do we have substantial information 
in our files, to suggest that climate change may threaten C. c. 
roselaari in the foreseeable future.
    In summary, we find that the information provided in the petition, 
as well as other information in our files, does not present 
``substantial scientific or commercial information'' indicating that 
the petitioned action of listing the roselaari subspecies may be 
warranted due to other natural or manmade factors affecting its 
continued existence.

Request To List a Broader Taxon Comprising Both the rufa and roselaari 
Subspecies

    We next evaluated whether the petition presents substantial 
information that the petitioned action of listing a broader taxon 
comprising both the rufa and roselaari subspecies may be warranted. 
However, the only taxonomic unit broader than a ``subspecies'' is a 
``species,'' and the petition does not seek to have the red knot 
species, which consists of six subspecies, listed. As there is no 
broader taxonomic unit consisting of the C. c. rufa and roselaari 
subspecies together, the Service concludes that the petitioned action 
of listing a broader taxon comprising both the C. c. rufa and roselaari 
subspecies does not involve a listable entity under the Act. 
Accordingly, based on the information set forth in the petition, 
information in the Service's files, and other readily available 
information, the petition does not present substantial scientific or 
commercial information that the petitioned action of listing a broader 
taxon comprising the rufa and roselaari subspecies may be warranted.

Request for National Listing Based on Similarity of Appearance

    The petitioner also seeks a ``national listing based on similarity 
of appearance'' under section 4(e) of the Act, ``[g]iven the potential 
overlap of rufa and roselaari populations within the southeastern 
United States.'' As a result, we have evaluated whether the petition 
presents substantial information that ``a national listing'' based on 
the similarity of appearance between the C. c. rufa and C. c. roselaari 
subspecies may be warranted.
    Under section 4(e) of the Act, a species not otherwise qualifying 
as endangered or threatened may be listed based on its close 
resemblance to a listed species if certain circumstances exist. 
Specifically, section 4(e) of the Act states, ``The Secretary may, by 
regulation of commerce or taking, and to the extent that he deems 
advisable, treat any species as an endangered species or threatened 
species even though it is not listed pursuant to section 4 of the Act 
if he finds that--
    (A) Such species so closely resembles in appearance, at the point 
in question, a species which has been listed pursuant to such section 
that enforcement personnel would have substantial difficulty in 
attempting to differentiate between the listed and unlisted species;
    (B) The effect of this substantial difficulty is an additional 
threat to an endangered or threatened species; and
    (C) Such treatment of an unlisted species will substantially 
facilitate the enforcement and further the policy of this Act.''
    In short, a threshold requirement for listing a species under 
section 4(e) of the Act is that the species must closely resemble in 
appearance ``a species which has been listed'' such that enforcement 
personnel would have substantial difficulty in differentiating the 
listed and unlisted species. In this instance, however, neither C. c. 
rufa or C. c. roselaari are listed under the Act. Therefore, the 
petition does not present a basis for concluding that a resemblance 
between the two subspecies would create difficulty for enforcement 
personnel in attempting to differentiate between a listed and unlisted 
entity. More importantly, however, we are aware of no evidence, and 
none was provided by the petitioners, that commerce or taking of C. c. 
rufa (which, as a candidate species, may be listed in the near future) 
poses a threat to the subspecies, and that confusion with C. c. 
roselaari on the part of enforcement personnel contributes to this 
threat. All subspecies of red knots are protected by the MBTA and 
cannot legally be hunted, imported into, or exported from the United 
States. Accordingly, we find that the petition does not present 
substantial information that listing either C. c. rufa or C. c. 
roselaari based on their similarity of appearance to each other under 
section 4(e) of the Act may be warranted.

Finding

    In summary, the petition does not present substantial information 
that the petitioned actions may be warranted. Specifically, the 
petition does not present substantial information that listing C. c. 
roselaari as endangered may be warranted because no specific 
information was provided on threats. The petition (p. 4) asserts that 
the Service should consider listing C. c. roselaari because its 
population ``is small (probably less than 10,000) and therefore 
vulnerable.'' However, uncertainty currently exists regarding the 
population size and trend of this subspecies. In addition, in the 
absence of information identifying threats to the subspecies and 
linking those threats to the rarity of the species, the Service does 
not consider rarity alone to be a threat.
    On the basis of our determination under section 4(b)(3)(A) of the 
Act, we conclude that the petition does not present ``substantial 
scientific or commercial information'' to indicate that listing C. c. 
roselaari under the Act may be warranted. Although we will not review 
the status of the species at this time, we encourage interested parties 
to continue to gather data that will assist with the conservation of C. 
c. roselaari. The Service is continuing to monitor the subspecies, and 
studies are ongoing. If new information on the status or distribution 
of C. c. roselaari is revealed at the conclusion of current studies, we 
will evaluate the new information. If you wish to provide information 
regarding C. c. roselaari, you may submit your information or materials 
to the Field Supervisor, Fairbanks Fish and Wildlife Field Office (see 
ADDRESSES), at any time.
    In addition, we find that the petition does not present substantial 
information that the petitioned action of listing ``a broader taxon 
comprising both the rufa subspecies and the roselaari subspecies'' may 
be warranted because the petitioned action does not involve a listable 
entity. Moreover, we find that the petition does not present 
substantial information that a ``national listing based on similarity 
of appearance'' under section 4(e) of the Act may be warranted because 
there is no listed species and, thus, no need for enforcement personnel 
to differentiate between a listed and unlisted entity. Additionally, 
the petition does not present substantial information that commerce or 
taking of C. c. rufa (which as a candidate species, may be listed in 
the near future) poses a threat to the subspecies, and that confusion 
with C. c. roselaari on the part of enforcement personnel contributes 
to this threat. All subspecies of red knots are protected by the MBTA 
and cannot legally be hunted, imported into, or exported from the 
United States. Accordingly, we find that the petition does not present 
substantial information that listing either C. c. rufa or C. c. 
roselaari based on their similarity of appearance to each other under 
section 4(e) of the Act may be warranted.

References Cited

    A complete list of references cited is available on the Internet at 
https://

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www.regulations.gov and upon request from the Fairbanks Fish and 
Wildlife Field Office (see ADDRESSES).

Authors

    The primary authors of this notice are the staff members of the 
Fairbanks Fish and Wildlife Field Office (see ADDRESSES).

Authority

    The authority for this action is the Endangered Species Act of 
1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: December 8, 2010.
Rowan W. Gould,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2010-33187 Filed 1-3-11; 8:45 am]
BILLING CODE 4310-55-P