[Federal Register Volume 73, Number 250 (Tuesday, December 30, 2008)]
[Notices]
[Pages 79822-79828]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-31023]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[Docket No. 080318443-81628-02]
RIN 0648-XG53


Endangered and Threatened Wildlife; Notice of 12-Month Finding on 
a Petition to List the Ribbon Seal as a Threatened or Endangered 
Species

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Status review; notice of finding.

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SUMMARY: We, NMFS, announce a 12-month finding on a petition to list 
the ribbon seal (Histriophoca fasciata) as a threatened or endangered 
species under the Endangered Species Act of 1973 as amended (ESA). 
After a formal review of the best available scientific and commercial 
information, we find that listing of the ribbon seal is not warranted 
at this time. Although the ribbon seal population abundance is likely 
to decline gradually for the foreseeable future, primarily from slight 
but chronic impacts on reproduction and survival caused by reduced 
frequency of years with sea ice of suitable extent, quality, and 
duration of persistence, it is not in danger of extinction or likely to 
become an endangered species within the foreseeable future throughout 
all or a significant portion of its range.

DATES: The finding announced in this notice was made on December 30, 
2008.

ADDRESSES: Information used to make this finding is available for 
public inspection by appointment during

[[Page 79823]]

normal business hours at the office of NMFS Alaska Region, Protected 
Resources Division, 709 West Ninth Street, Room 461, Juneau, AK 99801. 
This file includes the status review report, information provided by 
the public, and scientific and commercial information gathered for the 
status review. The ribbon seal petition and the status review report 
can also be found at http://www.fakr.noaa.gov/protectedresources/seals/ice.htm.

FOR FURTHER INFORMATION CONTACT: James Wilder, NMFS Alaska Region, 
telephone (907) 271-6620; Kaja Brix, NMFS Alaska Region, (907) 586-
7235; or Marta Nammack, NMFS, Office of Protected Resources, (301) 713-
1401.

SUPPLEMENTARY INFORMATION: On December 20, 2007, we received a petition 
from the Center for Biological Diversity to list the ribbon seal as a 
threatened or endangered species under the ESA, primarily due to 
concern about threats to this species' habitat from climate warming and 
loss of sea ice. The Petitioner also requested that critical habitat be 
designated for ribbon seals concurrently with listing under the ESA. 
Section 4(b)(3)(B) of the ESA requires that when a petition to revise 
the List of Endangered and Threatened Wildlife and Plants is found to 
present substantial scientific and commercial information, we make a 
finding on whether the petitioned action is (a) not warranted, (b) 
warranted, or (c) warranted but precluded from listing by other pending 
proposals of higher priority. This finding is to be made within 12 
months of the date the petition was received, and the finding is to be 
published promptly in the Federal Register.
    After reviewing the petition, the literature cited in the petition, 
and other literature and information available in our files, we found 
that the petition met the requirements of the regulations under 50 CFR 
424.14(b)(2) and determined that the petition presented substantial 
information indicating that the petitioned action may be warranted. 
This finding was published on March 28, 2008 (73 FR 16617). At that 
time, we commenced a status review of ribbon seals and solicited 
information pertaining to the species. We concurrently initiated status 
reviews of three other ice seals (ringed (Phoca hispida), bearded 
(Erignathus barbatus), and spotted (Phoca largha). These reviews are 
still ongoing. The status review of the ribbon seal is a compilation of 
the best available information concerning the status of ribbon seals, 
including the past, present, and future threats to this species. The 
Biological Review Team (BRT) that conducted the status review was 
composed of scientists with expertise in the biology and ecology of 
ribbon seals and with expertise in fisheries from NMFS' Alaska 
Fisheries Science Center and a climate expert from NOAA's Pacific 
Marine Environmental Lab. The Status Review produced by the BRT was 
reviewed by four independent scientific experts, three of whom have 
expertise in the biology and ecology of Arctic marine mammal species, 
and specifically with ribbon seals, and the fourth expert is a climate 
scientist. The reviewers agreed with the conclusions of the status 
review and provided detailed comment, which the BRT addressed in the 
final draft of the document.
    There are two key tasks associated with conducting an ESA status 
review. The first is to determine whether the petitioned entity 
qualifies as one or more species under the ESA; if so, or if we 
determine that there is a larger entity that includes the petitioned 
entity and qualifies as a species under the ESA, the second task is to 
conduct an extinction risk assessment to determine whether the species 
is threatened or endangered. The ESA defines the term endangered 
species as ``any species which is in danger of extinction throughout 
all or a significant portion of its range.'' The term threatened 
species is defined as ``any species which is likely to become 
endangered within the foreseeable future throughout all or a 
significant portion of its range.'' For this status review, the 
foreseeable future was determined to be the year 2050 because past and 
current emissions of greenhouse gases have already largely set the 
course for changes in the atmosphere and climate until that time, and 
because of enormous uncertainty about future social and political 
decisions on emissions that will dominate projection of conditions 
farther into the future. Beyond the year 2050, projections of climate 
scenarios are too heavily dependent on socio economic assumptions and 
are therefore too divergent for reliable use in assessing threats to 
ribbon seals.
    It is important to note that our approach to establishing the 
appropriate time frame for the foreseeable future, as noted above, was 
the same as the approach used by the U.S. Fish & Wildlife Service 
(USFWS) in its recent decision listing the polar bear as threatened 
under the ESA (73 FR 28212). Although not relied on as the basis for 
determining ``foreseeable future'' in the polar bear listing, the USFWS 
also noted that the mid century threshold for reliable assessment of 
threats will occur in about three polar bear generation lengths, or a 
total of 45 years from now, a measure that had been used previously by 
polar bear scientific expert groups as an appropriate time frame over 
which to evaluate polar bear population trends for determining the 
conservation status of the species. Coincidentally, the generation 
length of the ribbon seal (defined as the average age of the parents of 
an annual cohort or as the average age at which females give birth) is 
likely to be similar to that of the polar bear, approximately 12 15 
years. However, for the reasons stated above related to the uncertainty 
in climate change projections beyond 2050, we believe that using 2050 
as the foreseeable future is more appropriate with respect to ribbon 
seals than using a specific number of generation lengths to support or 
adjust the time frame for the foreseeable future. For species with 
overlapping generations, like the ribbon seal, facing threats that are 
primarily extrinsic, such as habitat destruction, commercial harvest, 
or incidental mortality in fisheries, the generation length may be 
essentially irrelevant; threats could undermine a population over the 
course of many generations or, conceivably, in less than one. Moreover, 
the time required to detect a specific change or trend in a population 
depends mostly on the precision of population estimates, not the 
generation time of the species. Therefore, and in summary, we 
determined that the best available scientific information allows 
reliable assessment of global warming and the related threats to ribbon 
seals through 2050. Further discussion of how the foreseeable future 
was defined for this analysis can be found in Section 4.1, Time Frame: 
The Foreseeable Future, of the Status Review of the Ribbon Seal.

Species Background

    The ribbon seal is a strikingly marked member of the family 
Phocidae that primarily inhabits the Sea of Okhotsk, and the Bering and 
Chukchi Seas. This species is strongly associated with the sea ice 
during its whelping, mating, and pelage molt periods, from mid March 
through June. Most of the rest of the year is spent at sea; the species 
is rarely observed on land. The rates of survival and reproduction are 
not well known, but ribbon seals can live 20 to 30 years. They become 
sexually mature at 1 to 5 years of age, probably depending on 
environmental conditions, and adult females usually give birth every 
year to a single pup which is nursed for 3 to 4 weeks and then 
abandoned to fend for itself.

[[Page 79824]]

Species Delineation

    The ESA provides for listing species, subspecies, or distinct 
population segments (DPSs) of vertebrate species. When we evaluate a 
petition to list an entity as threatened or endangered under the ESA, 
we must first determine whether the petitioned entity qualifies as a 
species under the ESA. The Petitioner requested that we list the ribbon 
seal species as threatened or endangered. When conducting a status 
review, we can also evaluate the status of DPSs of a vertebrate species 
to determine whether one or more warrant listing under the ESA.
    The joint NMFS/ USFWS policy on the Recognition of Distinct 
Vertebrate Population Segments (DPS) Under the Endangered Species Act 
(61 FR 4722; February 7, 1996) describes two criteria that a population 
segment must meet in order to be considered a DPS: (1) discreteness 
from other conspecific population segments; and (2) significance to the 
taxon to which it belongs. Although there are two main breeding areas 
for ribbon seals, one in the Sea of Okhotsk and one in the Bering Sea, 
there is currently no evidence of discrete populations on which to base 
a separation into DPSs. Therefore, the entire global population was 
considered to comprise the species for the purpose of assessing 
extinction risk. More detail on this determination can be found in 
Section 3 of the Status Review, Species Delineation. In assessing 
extinction risk, the BRT considered whether any of the threats set 
forth below posed a risk to the species throughout all or a significant 
portion of its range, as a species may be endangered or threatened even 
if it is at risk in only a significant portion of its range.

Extinction Risk Assessment

    To assess the extinction risk, the BRT evaluated the risks based on 
specific demographic factors of the species, such as abundance, 
productivity, spatial structure, and diversity, as these relate to the 
specific threats faced by the species outlined in section 4(a)(1) of 
the ESA. These threats are the present or threatened destruction, 
modification, or curtailment of its habitat or range; overutilization 
for commercial, recreational, scientific, or educational purposes; 
disease or predation; the inadequacy of existing regulatory mechanisms; 
or other natural or manmade factors affecting its continued existence. 
We evaluated whether these factors caused a risk of extinction 
throughout all or a significant portion of the ribbon seal's range.

Demographic Factors

    With a population likely comprising at least 200,000 individuals, 
ribbon seals are not currently at risk from the demographic issues of 
low abundance commonly associated with ESA listing decisions, such as 
demographic stochasticity, inbreeding, loss of genetic diversity, and 
depensatory effects. Aerial surveys were conducted in portions of the 
eastern Bering Sea by the National Marine Mammal Laboratory (NMML) in 
2003, 2007, and 2008. The data from these surveys are currently being 
analyzed to construct estimates of abundance for the eastern Bering Sea 
from frequencies of sightings, ice distribution, and the timings of 
seal haul out behavior. In the interim, NMML researchers have developed 
a provisional population estimate of 49,000 ribbon seals in the eastern 
and central Bering Sea. Using restrictive assumptions, this number was 
scaled according to distributions of ribbon seal breeding areas in 1987 
to produce total Bering Sea estimates ranging from 98,000 to 190,000. 
Similar scaling based on a rangewide distribution produced Bering Sea, 
Sea of Okhotsk, and total range estimates of 115,000, 100,000, and 
215,000, respectively. The current population trend is unknown, but the 
recent estimate of 49,000 ribbon seals in the eastern and central 
Bering Sea is consistent enough with historical estimates to suggest 
that no major or catastrophic change has occurred in recent decades. 
The species is thought to occupy its entire historically observed 
range. There are no portions of their range in which ribbon seals have 
been reported to have disappeared, nor are they known to be 
demographically at risk in any portion of their range. Further detail 
on historic and current abundance and trends can be found in Section 
2.9 of the ribbon seal status review.

 Present or Threatened Destruction, Modification, or Curtailment of the 
Species' Habitat or Range

    The main concerns about the conservation status of the ribbon seal 
stem from the likelihood that its sea ice habitat has been modified by 
the warming climate and, more so, that the scientific consensus 
projections are for continued and perhaps accelerated warming in the 
foreseeable future. A reliable assessment of the future conservation 
status of ribbon seals, therefore, requires a focus on projected 
changes to specific regional conditions, particularly sea ice, which 
could impact vital rates.
    Unlike the Arctic Ocean, where sea ice is present year round, the 
ice in the Bering Sea and Sea of Okhotsk is seasonal in nature. The 
main thermodynamic physical influence at high latitudes is the cold and 
darkness that occurs in winter. Therefore, despite the recent dramatic 
reductions in Arctic Ocean ice extent during summer, the sea ice in the 
northern Bering Sea and Sea of Okhotsk is expected to continue forming 
annually in winter for the foreseeable future. The future central 
Arctic will also continue to be an ice covered sea in winter, but will 
contain more first year sea ice than multi year ice.
    Ice extent in marginal seas such as the Bering Sea is characterized 
not by summer minima since these seas have been ice free in summer 
throughout recorded history but rather by winter maxima. Freezing 
conditions in the northern Bering Sea persist from December through 
April. Mean monthly maximum temperatures at Nome, Alaska (a sub Arctic 
maritime climate station located at 64[deg] N), are -3[deg]C or below 
for all months November through April. Freezing rather than thawing 
should still predominate in these months even if a hypothesized ~3[deg] 
C global warming signal is realized. The result is that the seasonal 
formation of sea ice in the northern Bering Sea and Sea of Okhotsk is 
substantially decoupled from the summer ice extent in the Arctic Ocean, 
and is expected to continue annually through the foreseeable future, 
along with typical, large interannual variations in extent and duration 
of persistence.
    Large areas of sea ice in the ribbon seal's range will form and 
persist in most years through May; the occurrence of extensive ice in 
June will be highly variable, as it has been in the past. Nevertheless, 
in association with a long term warming trend there will likely be 
changes in the frequency of years with extensive ice, the quality of 
ice, and the duration of its persistence that may impact the amount of 
suitable habitat in the geographic areas that ribbon seals have 
preferred in the past. An assessment of the risks posed by these 
changes must consider the ribbon seal life history functions associated 
with sea ice and the potential effects on the vital rates of 
reproduction and survival.
    Despite the recent dramatic reductions in Arctic Ocean ice extent 
during summer, the sea ice in the northern Bering Sea and Sea of 
Okhotsk is expected to continue forming annually in winter for the 
foreseeable future. As mentioned above, the sea ice regimes in the 
Bering Sea and Sea of Okhotsk will continue to be subject to

[[Page 79825]]

large interannual variations in extent and seasonal duration, as they 
have been throughout recorded history. While there may be more frequent 
years in which sea ice coverage is reduced, the late March to early May 
period in which the peak of ribbon seal reproduction occurs will 
continue to have substantial ice for the foreseeable future. Still, 
there will likely be more frequent years in which the ice is confined 
to the northern regions of the observed breeding range.
    In contrast to harp seals (Pagophilus groenlandicus), which are 
their closest relatives, ribbon seals are much less closely tied to 
traditional geographic locations for important life history functions 
such as whelping and molting. In years of low ice it is likely that 
ribbon seals will adjust, at least in part, by shifting their breeding 
locations in response to the position of the ice edge, as they have 
likely done in the past in response to interannual variability. For 
example, observations indicate that extreme dispersal of ribbon seals 
within their effective range is associated with years of unusual ice 
conditions. The formation of extensive ice in the Bering and Okhotsk 
Seas has been found to result in the occurrence of large numbers of 
these seals further south than they normally occur. The reverse is also 
true.
    There has not been, however, any study that would verify whether 
vital rates of reproduction or survival have been affected by these 
interannual variations in ice extent and breeding. Whelping, nursing of 
pups, and maturation of weaned pups could conceivably be impacted in 
years when the ice does not extend as far south as it has typically in 
the past, because the breeding areas would be farther from the 
continental shelf break, a zone that seems to be a preferred foraging 
area during spring. If these conditions occur more frequently, as is 
anticipated from projections of future climate and sea ice conditions, 
reproduction and survival of young could be impacted. Lacking relevant 
data, the most conservative approach is to assume that the population 
has been at equilibrium with respect to conditions in the past, and 
that a change such as more frequent breeding farther from preferred 
foraging habitats will have some impact on vital rates. Even given the 
uncertainties, we conclude that the anticipated slight increase in 
frequency of years with low ice extent in April and May is likely to 
have some impact on reproductive rates.
    As described in Section 2.5 of the status review, ribbon seals have 
an apparent affinity for stable, clean, moderate sized ice floes that 
are slightly, but not deeply interior to the pack ice edge. For the 
foreseeable future, ice of this type is likely to occur annually in the 
Bering Sea and Sea of Okhotsk, but it may be confined more frequently 
to smaller areas, or areas farther north, than in the past. The 
availability of moderately thick, stable ice floes could potentially 
influence ribbon seal demography, particularly in May, via survival 
rates of weaned pups. Pups spend a great deal of time on the ice during 
a transition period of 2 3 weeks following weaning, presumably 
developing their capabilities for self sufficient foraging. They enter 
the water regularly during this period, and therefore may not be 
particularly sensitive to modest reductions in ice coverage or quality. 
Thus, although they are likely dependent on ice, weaned pups may not 
require ice floes that can persist for weeks to meet their basic haul 
out needs. Though uncertain, it is possible that the weaned pups will 
be relatively limited in their capability to respond to rapidly 
deteriorating ice fields by relocating over large distances, a factor 
that could occur more frequently in the foreseeable future.
    Subadult ribbon seals, which molt earlier than adults during March 
to mid May, and which are not constrained by habitat requirements for 
whelping and breeding, may be the least sensitive to the availability 
and quality of sea ice. For example, in 2007, NMFS research cruises in 
the Bering Sea encountered subadult ribbon seals in approximately the 
expected proportions. Of 31 ribbon seals caught, 6 were subadults, 22 
were adults, and 3 were young of the year (which were commonly 
encountered but not always pursued for tagging). In other words, the 
obvious presence of seals in the subadult age class did not indicate 
that catastrophic losses had occurred in the ribbon seal cohorts 
produced during the warm years of 2001 2005.
    Adult ribbon seals, which are the last to molt, might be expected 
to be the most sensitive to timing of the ice melt. Stable ice is 
critical during this period, and ribbon seals have been observed to 
rarely enter the water during this time. The pelage molt of phocid 
seals is generally thought to be facilitated or enhanced by elevated 
skin temperatures that can be achieved when hauled out versus in the 
water. For example, it has been suggested that the harbor seal (Phoca 
vitulina, a small phocid, similar in size and body composition to a 
ribbon seal), could not complete its molt entirely in the water at 
temperatures that the species would normally encounter in the wild. 
Analysis of haul out records (Section 2.6, Life History, of the status 
review) indicate that individual adult ribbon seals haul out almost 
continuously for a period of 2 3 weeks, mostly during mid May to late 
June, corresponding to the observed peak in molting. Therefore, 
decreased availability of stable platforms for adults to complete their 
molt out of the water may also lower survival, but it is not currently 
possible to quantify this impact or the extent to which ribbon seals 
may adapt by shifting locations for molting.
    Sea ice coverage in June will likely be low or absent more 
frequently in the foreseeable future. The implications of a loss of 
access to a haul out substrate during this period are unknown, but they 
may include energetic costs, increased susceptibility to skin disorders 
and pathogens, and possibly increased exposure to any risks from which 
the hair normally protects a seal (e.g., abrasion from crawling over 
snow and ice). However, the ultimate effect on adult survival rate is 
currently difficult or impossible to model.
    These impacts on ribbon seal survival in years of low ice extent, 
poor ice quality, or early melting are all of a sort that would not 
necessarily be significant in any one year; a year of low ice extent 
seems unlikely to cause widespread mortality through disruption of the 
adult molt, or increased energetic costs for pups developing their 
foraging capabilities. Rather, the overall strength of the impacts is 
likely a function of the frequency of years in which they occur, and 
the proportion of the population's range over which they occur. Also, 
the effects on different age classes might be expected to be 
correlated, though not always in concert, because they involve ice 
characteristics at different times in the breeding molting period; low 
ice extent during breeding may not always be accompanied by early 
melting, and vice versa. As above, in the assessment of impacts on 
reproduction, we conclude that the anticipated slight increase in 
frequency of years with low ice extent in May and June is likely to 
have some impact on survival rates.
    The extent to which ribbon seals will adapt to more frequent years 
with early ice melt by shifting the timing of reproduction and molting 
is unknown. Peak whelping dates of harbor seals at Tugidak Island, 
Alaska were 9 14 days earlier in 1964 and in the mid 1990s than in the 
late 1970s. The changes were unlikely to be caused by shifts in the age 
structure coupled with age specific differences in timing of 
reproduction, and therefore may have been a response to changes in 
environmental conditions. There are many examples in the scientific 
literature of shifts in the timing of reproduction by pinnipeds

[[Page 79826]]

and terrestrial mammals in response to body condition and food 
availability. In most of these cases, sub optimal conditions led to 
later reproduction, which would not likely be beneficial to ribbon 
seals as a phenotypic response to earlier spring ice melt. Over the 
longer term (i.e. beyond the foreseeable future) a shift to an earlier 
mean melt date may provide selection pressure for an evolutionary 
response over many generations toward earlier reproduction.
    Several factors are noteworthy for their potential to mitigate the 
impacts on ribbon seals from predicted future sea ice scenarios. First, 
adult ribbon seals may be less constrained to a specific geographic 
area or region of the ice pack once breeding is complete, around the 
onset of the adult molt. They may therefore be capable of considerable 
shifts in distribution to ensure contact with suitable ice through the 
molt period, especially in the Bering Sea where there is access through 
the Bering Strait to the Chukchi Sea, in which ice persists more 
frequently in June. Second, the models on which we based our assessment 
of future ice conditions used a spatial resolution (~1[deg] of 
latitude) that is much coarser than the scale at which ribbon seals are 
likely to interact with fields of sea ice. Model scenarios, and the 
remote sensed ice data that have been used to fit and tune the models, 
may depict zero ice in areas where ribbon seals remain capable of 
finding suitable ice. For example, in June 2008 the NOAA ship Oscar 
Dyson encountered a field of ice with numerous ribbon and spotted seals 
(Phoca largha) at 60[deg]N near St. Matthew Island, an area where no 
ice was visible on the relatively high resolution (12.5 km) satellite 
images of sea ice for that day. And third, the age of maturation for 
females has been very low and pregnancy rates have been high in the 
recent past (Section 2.7, Vital Parameters, of the Status Review), 
implying that foraging conditions have been favorable, a scenario more 
likely to reflect population growth rather than equilibrium; if so, 
there may be some capacity to withstand a reduction in vital rates 
without incurring an actual population decline.
    In summary, more frequent future years of reduced spring ice extent 
or ice quality could result in reduced vital rates of ribbon seal 
reproduction and survival. These potential impacts are premised on the 
assumption of a population at equilibrium with conditions in the recent 
(cooler) past and the related possibility that changes such as 
displacement of breeding locations or reduced availability of preferred 
ice types will have some energetic costs that will ultimately be 
reflected in vital rates. In the absence of relevant data, it is not 
feasible to state the quantitative magnitude of the anticipated 
impacts. Considering both the potential impacts and the factors 
potentially conferring resilience, the BRT concluded that the net 
impacts will be slight but chronic and likely to cause a gradual 
decline in the ribbon seal population, but such decline is of 
insufficient magnitude to place it in danger of extinction throughout 
all or a significant portion of its range, now or within the 
foreseeable future.
    In light of the recent decision to list the polar bear as 
threatened under the ESA, we note that the nature of ribbon seals' 
relationship to sea ice is different from that of polar bears in 
several significant respects. Ribbon seals' strong association with sea 
ice occurs in sub Arctic seas, whereas polar bears are distributed 
throughout most ice covered seas of the Northern Hemisphere, and 
particularly in the Arctic Ocean. The seasonal contrast in the two 
species' relationships with sea ice is also important. Ribbon seals use 
annually formed sea ice for reproduction and molting in the spring, but 
are largely unassociated with sea ice during summer, autumn, and early 
winter, whereas most polar bears remain on the sea ice year round or 
spend only short periods of time on land. Most polar bears rely on the 
persistence of sea ice over productive continental shelf waters, where 
they have both access to food (primarily ringed seals, Phoca hispida) 
within the sea ice habitat and proximity to terrestrial denning areas. 
Thus, the recent severe decline in the extent of summer sea ice, 
particularly multi year ice, of the Arctic Ocean was a primary factor 
in the conclusion that the polar bear should be considered threatened. 
The further retreat of the summer sea ice into the Arctic polar basin 
will force polar bears into increasingly marginal sea ice habitat over 
relatively unproductive polar basin waters, or into terrestrial areas 
lacking preferred prey and associated with increased competition and 
human interactions. The increasing separation between the summer ice 
edge and terrestrial denning areas will also subject polar bears to 
increased open water swimming and risk of drowning. Ribbon seals, on 
the other hand, are anticipated to experience little or no direct 
effects from the further retreat of summer sea ice in the Arctic polar 
basin, as they are primarily a pelagic, sub Arctic species during the 
summer months.
    Ocean acidification, a result of increased carbon dioxide in the 
atmosphere, may impact ribbon seal survival and recruitment through 
disruption of trophic regimes that are dependent on calcifying 
organisms. The nature and timing of such impacts are, however, 
extremely uncertain. Because of ribbon seals' apparent dietary 
flexibility (Section 2.8 of the status review, Feeding Habits) and 
because the major effects expected as a result of ocean acidification 
may not appear until the latter half of this century, this threat is of 
less immediate concern than the direct effects of sea ice degradation. 
Further details on ocean acidification can be found in Section 
4.3.1.1.4.2 of the status review.
    Changes in ribbon seal prey, anticipated in response to habitat 
changes resulting from ocean warming and loss of sea ice, have the 
potential for negative impacts, but these impacts are not well 
understood. Some changes already documented in the Bering Sea and the 
North Atlantic Ocean are of a nature that could be ameliorative or 
beneficial to ribbon seals. For example, several fish species, 
including walleye pollock (Theragra chalcogramma), a common ribbon seal 
prey, have shown northward distribution shifts and increased 
recruitment in response to warming, at least initially. These ecosystem 
responses may have very long lags as they propagate through trophic 
webs. The apparent flexibility in ribbon seal foraging locations and 
habits may make these threats of lower concern than more direct impacts 
from changes in sea ice.
    The above analyses of the threats associated with impacts of global 
warming on ribbon seal habitat, to the extent that they may pose risks 
to ribbon seals, were presumed to manifest throughout the current 
breeding and molting range (for sea ice related threats) or throughout 
the entire range (for ocean warming and acidification) of the species, 
inasmuch as the finer scale spatial distribution of these threats is 
not currently well understood. The analysis did not indicate that any 
of these threats place the species in danger of extinction, now or in 
the foreseeable future, in a significant portion of its range or its 
entire range. More detailed information on the present or threatened 
destruction, modification, or curtailment of ribbon seals' habitat or 
range can be found in Section 4.3.1 of the status review.

Over-Utilization for Commercial, Subsistence, Recreational, Scientific, 
or Educational Purposes

    Recreational, scientific, and educational utilization of ribbon 
seals is currently at very low levels and is not

[[Page 79827]]

projected to increase to significant threat levels in the foreseeable 
future. Commercial harvests by Russian sealers have at times been high 
enough to cause significant reductions in abundance and catch-per unit 
effort. The population apparently rebounded from a period of high 
harvest in the 1960s. Substantial but lower numbers were harvested for 
a few years in the early 1990s. Although Russian government quotas were 
recently put in place that would allow large harvests (~18,000 
annually), the actual takes are low because of poor economic viability. 
There is some effort in Russia to develop new uses and markets for seal 
products, but unless this effort is successful, the harvest is unlikely 
to increase in the near future. Subsistence harvest levels have been 
low historically, but could potentially increase in the future if 
ribbon seals are forced to use a reduced and more northerly ice field, 
which could put them in closer proximity to Alaska Native communities 
near the Bering Strait. Changes in subsistence or commercial takes 
cannot be predicted with any certainty at this time. There is no 
indication that illegal harvests are occurring.

Diseases, Parasites, & Predation

    A variety of pathogens (or antibodies), diseases, helminthes, 
cestodes, and nematodes have been found in ribbon seals. The prevalence 
of these agents is not unusual among seals, but the population impact 
is unknown. There may be an increased risk of outbreaks of novel 
pathogens or parasites as climate related shifts in species 
distributions lead to new modes of transmission. There is little or no 
direct evidence of significant predation on ribbon seals, and they are 
not thought to be a primary prey of any predators. Polar bears and 
killer whales may be the most likely opportunistic predators in the 
current sea ice regime, but walruses could pose a potentially greater 
risk if reduced sea ice conditions force these pagophilic (ice-loving) 
species into closer proximity in the future.

Inadequacy of Existing Regulatory Mechanisms

    There is little evidence that the inadequacy of existing regulatory 
mechanisms currently poses a threat to ribbon seals throughout all or a 
significant portion of their range. However, there are no known 
regulatory mechanisms that effectively address global reductions in sea 
ice habitat at this time. Also, it is unclear what regulatory 
mechanisms are in place to ensure that potential commercial harvests in 
Russia are conducted in a sustainable fashion.

Other Natural or Manmade Factors Affecting the Species' Continued 
Existence

    Although some pollutants are elevated in ribbon seals, there is no 
conspicuous evidence of toxicity or other significant impacts to the 
species throughout all or a significant portion of its range. Continued 
and expanded monitoring would be prudent to document any trends in the 
contaminants of greatest concern.
    Oil and gas exploration and development activities may include 
artificial island construction, drilling operations, pipeline 
construction, seismic surveys, and vessel and aircraft operations. The 
main issues for evaluating the impacts of exploration and development 
activities on ribbon seals are the effects of noise, disturbance, and 
potential oil spills produced from these activities. Any negative 
effects on ribbon seals from noise and disturbance associated with 
development activities are likely to be minor and localized. Ribbon 
seals are also highly dispersed during the summer, open water season, 
so the rate of interactions with seismic surveys would likely be low, 
and, in any case, seals have not been shown to be significantly 
impacted by oil and gas seismic surveys. The threat posed to ribbon 
seals by oil spills will increase if offshore oil and gas development 
and shipping activities increase across their range as predicted. The 
potential impacts would be greatest during April June when the seals 
are relatively aggregated, and substantially lower during the remainder 
of the year when they are dispersed in the open water throughout the 
North Pacific Ocean, Sea of Okhotsk, and Bering and Chukchi Seas.
    Estimates from observed bycatch in commercial fisheries indicate 
that less than 200 ribbon seals per year are taken, though mortalities 
are certainly under reported in some fisheries. However, this level of 
estimated bycatch of ribbon seals represents less than 0.1% of their 
estimated population. Because there is little or no fishery activity 
near aggregations of ribbon seals when they are associated with ice, 
and they are highly dispersed during the remainder of the year, bycatch 
is unlikely to be a significant threat to ribbon seal populations. For 
the same reason, competition from fisheries that reduce local abundance 
of ribbon seal prey is unlikely to be significant. Broad scale 
reduction in a commercially fished, primary prey species could have a 
significant impact, but the large groundfish fisheries in Alaskan 
waters are managed to prevent depletion of the stocks.
    The extraordinary reduction in Arctic sea ice that has occurred in 
recent years has renewed interest in trans Arctic navigation routes 
connecting the Atlantic and Pacific Oceans via the Northwest Passage 
and the Northern Sea Route. The Chukchi Sea and Bering Strait would be 
the most likely areas for increased exposure of pelagic ribbon seals to 
ship traffic, because of the geographic constriction and the seasonal 
migration of part of the ribbon seal population around the beginning 
and end of the ice-free season. However, there is currently little or 
no information on direct impacts from shipping on seals in open water. 
Ribbon seals hauled out on sea ice may also be at risk from increased 
ship traffic, but likely only during spring and early summer, and then 
only by ice reinforced ships. Assessing risk from increases in shipping 
and transportation is difficult because projections about future ship 
trends within the ribbon seal's range are currently unavailable.
    Several of the threats considered in this section were associated 
with specific regions or times of year when ribbon seal distribution is 
restricted, such as increased ship traffic in the Bering Strait region 
or oil and gas activities during the ribbon seal breeding and molting 
seasons. If such threats were to occur and cause a high rate of 
mortality or forgone reproduction, the species could be considered 
threatened or endangered in a significant portion of its range. 
However, none of the threats considered here is presently considered to 
be both sufficiently likely to occur and sufficiently high in impact, 
alone or cumulatively, to raise concern about them posing a risk of 
ribbon seal extinction or becoming endangered throughout a significant 
portion of its range.

Conservation Efforts

    When considering the listing of a species, section 4(b)(1)(A) of 
the ESA requires consideration of efforts by any state, foreign nation, 
or political subdivision of a state or foreign nation to protect the 
species. Such efforts would include measures by Native American tribes 
and organizations, local governments, and private organizations. Also, 
Federal, tribal, state, and foreign recovery actions (16 U.S.C. 
1533(f)), and Federal consultation requirements (16 U.S.C. 1536) 
constitute conservation measures. On March 28, 2003, NMFS and the U.S. 
Fish and Wildlife Service

[[Page 79828]]

(USFWS) published the final Policy for Evaluating Conservation Efforts 
(PECE)(68 FR 15100). The PECE provides guidance on evaluating current 
protective efforts identified in conservation agreements, conservation 
plans, management plans, or similar documents (developed by Federal 
agencies, state and local governments, tribal governments, businesses, 
organizations, and individuals) that have not yet been implemented, or 
that have been implemented but have not yet demonstrated effectiveness. 
The PECE establishes two basic criteria for evaluating current 
conservation efforts: (1) the certainty that the conservation efforts 
will be implemented, and (2) the certainty that the efforts will be 
effective. The PECE provides specific factors under these two basic 
criteria that direct the analysis of existing conservation efforts.
    The PECE identifies a number of factors to consider when evaluating 
the certainty an effort will be implemented. These include whether: the 
necessary resources (e.g., funding and staffing) are available; the 
necessary agreements have been formalized such that the required 
authority and regulatory mechanisms are in place; there is a schedule 
for completion and evaluation of the stated objectives; and (for 
voluntary efforts) the necessary incentives are in place to ensure 
adequate participation. The evaluation of the certainty of an effort's 
effectiveness is made on the basis of whether the effort or plan: (1) 
establishes specific conservation objectives; (2) identifies the 
necessary steps to reduce threats or factors for decline; (3) includes 
quantifiable performance measures for the monitoring of compliance and 
effectiveness; (4) incorporates the principles of adaptive management; 
and (5) is likely to improve the species' viability at the time of the 
listing determination.
    The PECE identifies several important stipulations. Satisfaction of 
the criteria for implementation and effectiveness establishes a given 
conservation effort as a candidate for consideration, but does not mean 
that the effort will ultimately change the risk assessment. The PECE 
stresses that, just as listing determinations must be based on the 
viability of the species at the time of review, they must also be based 
on the state of protective efforts at the time of the listing 
determination. There are circumstances where threats are so imminent, 
widespread, and/or complex that it may be impossible for any agreement 
or plan to include sufficient efforts to result in a determination that 
listing is not warranted.
    At this time, we are not aware of any formalized conservation 
efforts for ribbon seals that have yet to be implemented, or which have 
recently been implemented, but have yet to show their effectiveness in 
removing threats to the species. NMFS co-manages ribbon seals with the 
Ice Seal Committee (ISC), which is an Alaska Native Organization 
dedicated to conserving seal populations, habitat, and hunting in order 
to help preserve native cultures and traditions. The ISC co-manages ice 
seals with NMFS by monitoring subsistence harvest and cooperating on 
needed research and education programs pertaining to ice seals. Our 
National Marine Mammal Lab is engaged in an active research program for 
ribbon seals. The new information from research will be used to enhance 
our understanding of the risk factors affecting ribbon seals, thereby 
improving our ability to develop effective management measures for the 
species.
    ESA section 4(b)(1)(B) requires us to give consideration to species 
which have been designated as requiring protection from unrestricted 
commerce by any foreign nation, or pursuant to any international 
agreement; or identified as in danger of extinction, or likely to 
become so within the foreseeable future, by any state agency or any 
agency of a foreign nation that is responsible for the conservation of 
the species. We are not aware of any such special protections or 
designations, or of any conservation efforts undertaken by foreign 
nations specifically to protect ribbon seals. Ribbon seals are not 
afforded any protective measures or special status via the Convention 
for the International Trade in Endangered Species or the International 
Union for Conservation of Nature.
    In consideration of all of the threats and potential threats 
identified above, the assessment of the risks posed by those threats, 
the possible cumulative impacts, and the uncertainty associated with 
all of these, we draw the following conclusions: (1) Ribbon seals are 
not in current danger of extinction throughout all or a significant 
portion of their range; (2) the abundance of the ribbon seal population 
is likely to decline gradually for the foreseeable future, primarily 
from slight but chronic impacts on reproduction and survival caused by 
reduced frequency of years with sea ice of suitable extent, quality, 
and duration of persistence; (3) despite the expectation of a gradual 
decline, ribbon seals are not likely to become an endangered species 
within the foreseeable future throughout all or a significant portion 
of their range.
    We have reviewed the status of the ribbon seal, considering the 
best scientific and commercial data available. We have given 
consideration to conservation efforts and special designations for 
ribbon seals by states and foreign nations. Consideration of the ESA 
section 4(a)(1) factors in the context of the biological status of the 
species indicates that the species is not in danger of extinction 
throughout all or a significant portion of its range, nor is it likely 
to become so in the foreseeable future. We believe that the ribbon seal 
does not meet the ESA definition of an endangered or threatened 
species; therefore, the listing of ribbon seals under the ESA is not 
warranted at this time. However, we will continue to monitor the status 
of the ribbon seal. If conditions change in the future, we will re-
evaluate the status of this species to determine whether it should be 
listed as threatened or endangered under the ESA. Because of the 
remaining uncertainties regarding the effects of climate change, sea 
ice cover, and potential Russian harvests, we will add the ribbon seal 
to our Species of Concern list (http://www.nmfs.noaa.gov/pr/species/concern/#list; See 69 FR 19975, April 15, 2004 for description of 
program). This will serve to (1) increase public awareness about the 
species; (2) further identify data deficiencies and uncertainties in 
the species' status and the threats it faces; (3) and stimulate 
cooperative research efforts to obtain the information necessary to 
evaluate the species' status and threats. As resources permit, we will 
conduct further studies of ribbon seal abundance and status. We will 
evaluate results of these and any other studies that may be conducted 
and undertake a new status review, if warranted.

Authority

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

    Dated: December 22, 2008.
Samuel D. Rauch III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.
[FR Doc. E8-31023 Filed 12-29-08; 8:45 am]
BILLING CODE 3510-22-S