We, NMFS, announce a 90-day finding on two petitions received to list the northeastern Pacific Ocean population of great white shark (Carcharodon carcharias) as a threatened or endangered distinct population segment (DPS) under the Endangered Species Act (ESA) and to designate critical habitat concurrently with the listing. We find that the petitions and information in our files present substantial scientific or commercial information indicating that the petitioned action may be warranted. We will conduct a status review of the species to determine if the petitioned action is warranted. To ensure that the status review is comprehensive, we are soliciting scientific and commercial information pertaining to this species from any interested party.
Information and comments on the subject action must be received by November 27, 2012.
ADDRESSES: You may submit comments, information, or data, identified by ``NOAA-NMFS-2012-0176'' by any one of the following methods:
Electronic Submissions: Submit all electronic comments via the Federal eRulemaking Portal http://www.regulations.gov. To submit comments via the e-Rulemaking Portal, first click the ``submit a comment'' icon, then enter ``NOAA-NMFS-2012-0176'' in the keyword search. Locate the document you wish to comment on from the resulting list and click on the ``Submit a Comment'' icon on the right of that line.
Mail or hand-delivery: Protected Resources Division, Southwest Region, NMFS, 501 West Ocean Blvd., Suite 4200, Long Beach, CA 90802-4213.
Instructions: All comments received are a part of the public record and may be posted to http://www.regulations.gov without change. All personally identifiable information (for example, name, address, etc.) voluntarily submitted by the commenter may be publicly accessible. Do not submit confidential business information or other information you wish to protect from public disclosure. NMFS will accept anonymous comments. Attachments to electronic comments will be accepted in Microsoft Word, Excel, Corel WordPerfect, or Adobe PDF file formats only.
FOR FURTHER INFORMATION CONTACT: Craig Wingert, NMFS, Southwest Region, (562) 980-4021; or Marta Nammack, NMFS, Office of Protected Resources, (301) 427-8469.
Background
On June 25, 2012, we received a petition from WildEarth Guardians
to list the northeastern Pacific Ocean DPS of great white shark
(Carcharodon carcharias) as threatened or endangered under the ESA. The
petitioners also requested that critical habitat be designated for this
DPS under the ESA. On August 13, 2012, we received a second petition,
filed jointly by Oceana, Center for Biological Diversity (CBD), and
Shark Stewards, to list the northeastern Pacific Ocean DPS of white
shark (another common name for the great white shark) under the ESA and
designate critical habitat. Both petitions bring forth much of the same
or related factual information on the biology and ecology of great
white sharks, and raise several identical or similar issues related to
potential factors affecting this species. As a result, we are
considering both petitions simultaneously in this 90-day finding.
Copies of the petitions are available upon request (see ADDRESSES,
above).
ESA Statutory, Regulatory, and Policy Provisions and Evaluation
Framework
Section 4(b)(3)(A) of the ESA of 1973, as amended (16 U.S.C. 1531
et seq.), requires, to the maximum extent practicable, that within 90
days of receipt of a petition to list a species as threatened or
endangered, the Secretary of Commerce make a finding on whether that
petition presents substantial scientific or commercial information
indicating that the petitioned action may be warranted, and to promptly
publish such finding in the Federal Register (16 U.S.C. 1533(b)(3)(A)).
When it is found that substantial scientific or commercial information
in a petition indicates the petitioned action may be warranted (a
``positive 90-day finding''), we are required to promptly commence a
review of the status of the species concerned during which we will
conduct a comprehensive review of the best available scientific and
commercial information. In such cases, we conclude the status review
with a finding published in the Federal Register as to whether or not
the petitioned action is warranted within 12 months of receipt of the
petition. Because the finding at the 12-month stage is based on a
thorough review of the available information, as compared to the more
limited scope of review at the 90-day stage, a ``may be warranted''
finding does not prejudge the outcome of the status review.
Under the ESA, a listing determination may address a species, which
is defined to also include any subspecies and, for vertebrate species,
any DPS which interbreeds when mature (16 U.S.C. 1532(16)). A joint
NMFS-U.S. Fish and Wildlife Service (USFWS) (jointly, ``the Services'')
policy clarifies the agencies' interpretation of the phrase ``distinct
population segment'' for the purposes of listing, delisting, and
reclassifying a species under the ESA (61 FR 4722; February 7, 1996). A
species, subspecies, or DPS is ``endangered'' if it is in danger of
extinction throughout all or a significant portion of its range, and
``threatened'' if it is likely to become endangered within the
foreseeable future throughout all or a significant portion of its range
(16 U.S.C. 1532(6) and (20)). Pursuant to the ESA and our implementing
regulations, we determine whether species are threatened or endangered
based on any one or a combination of the following factors: (1) The
present or threatened destruction, modification, or curtailment of its
habitat or range; (2) overutilization for commercial, recreational,
scientific, or educational purposes; (3) disease or predation; (4) the
inadequacy of existing regulatory mechanisms; and (5) any other natural
or manmade factors affecting the species' continued existence (16
U.S.C. 1533(a)(1), 50 CFR 424.11(c)).
ESA implementing regulations define ``substantial information'' in
the context of reviewing a petition to list, delist, or reclassify a
species as 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)). In evaluating whether substantial
information is contained in a petition, the Secretary must consider
whether the petition: (1) Clearly indicates the administrative measure
recommended and gives the scientific and any common name of the species involved;
(2) contains detailed narrative justification for the recommended
measure, describing, based on available information, past and present
numbers and distribution of the species involved and any threats faced
by the species; (3) provides information regarding the status of the
species over all or a significant portion of its range; and (4) is
accompanied by the appropriate supporting documentation in the form of
bibliographic references, reprints of pertinent publications, copies of
reports or letters from authorities, and maps (50 CFR 424.14(b)(2)).
Judicial decisions have clarified the appropriate scope and
limitations of the Services' review of petitions at the 90-day finding
stage, in making a determination that a petitioned action ``may be''
warranted. As a general matter, these decisions hold that a petition
need not establish a ``strong likelihood'' or a ``high probability''
that a species is either threatened or endangered to support a positive
90-day finding.
We evaluate the petitioners' request based upon the information in
the petition including its references and the information readily
available in our files. We do not conduct additional research and we do
not solicit information from parties outside the agency to help us in
evaluating the petition. We will accept the petitioners' sources and
characterizations of the information presented if they appear to be
based on accepted scientific principles, unless we have specific
information in our files indicating the petition's information is
incorrect, unreliable, obsolete, or otherwise irrelevant to the
requested action. Information that is susceptible to more than one
interpretation or that is contradicted by other available information
will not be dismissed at the 90-day finding stage, so long as it is
reliable and a reasonable person would conclude it supports the
petitioners' assertions. In other words, conclusive information
indicating the species may meet the ESA's requirements for listing is
not required to make a positive 90-day finding. We will not conclude
that a lack of specific information negates a positive 90-day finding
if a reasonable person would conclude that the uncertainty from the
lack of information suggests an extinction risk of concern for the
species at issue.
To make a 90-day finding on a petition to list a species, we
evaluate whether the petition presents substantial scientific or
commercial information indicating the subject species may be either
threatened or endangered, as defined by the ESA. First, we evaluate
whether the information presented in the petition, along with the
information readily available in our files, indicates that the
petitioned entity constitutes a ``species'' eligible for listing under
the ESA. Next, we evaluate whether the information indicates that the
species faces an extinction risk that is cause for concern; this may be
indicated in information expressly discussing the species' status and
trends, or in information describing impacts and threats to the
species. We evaluate any information on specific demographic factors
pertinent to evaluating extinction risk for the species (e.g.,
population abundance and trends, productivity, spatial structure, age
structure, sex ratio, diversity, current and historical range, habitat
integrity or fragmentation), and the potential contribution of
identified demographic risks to extinction risk for the species. We
then evaluate the potential links between these demographic risks and
the causative impacts and threats identified in section 4(a)(1).
Information presented on impacts or threats should be specific to
the species and should reasonably suggest that one or more of these
factors may be operative threats that act or have acted on the species
to the point that it may warrant protection under the ESA. Broad
statements about generalized threats to the species, or identification
of factors that could negatively impact a species, do not constitute
substantial information indicating that listing may be warranted. We
look for information indicating that not only is the particular species
exposed to a factor, but that the species may be responding in a
negative fashion; then we assess the potential significance of that
negative response.
Many petitions identify risk classifications made by non-
governmental organizations, such as the International Union on the
Conservation of Nature (IUCN), the American Fisheries Society, or
NatureServe, as evidence of extinction risk for a species. Risk
classifications by other organizations or made under other Federal or
state statutes may be informative, but the classification alone does
not provide the rationale for a positive 90-day finding under the ESA.
For example, as explained by NatureServe, their assessments of a
species' conservation status do ``not constitute a recommendation by
NatureServe for listing under the U.S. Endangered Species Act'' because
NatureServe assessments ``have different criteria, evidence
requirements, purposes and taxonomic coverage than government lists of
endangered and threatened species, and therefore these two types of
lists should not be expected to coincide'' (http://www.natureserve.org/prodServices/statusAssessment.jsp). Thus, when a petition cites such
classifications, we will evaluate the source of information that the
classification is based upon in light of the standards on extinction
risk and impacts or threats discussed above.
Distribution and Life History of the Great White Shark
The great white shark (also known as ``white shark'') is a
circumglobal species that resides primarily in temperate and sub-
tropical waters (Compagno et al., 1997; Domeier and Nasby-Lucas, 2006;
Domeier et al., 2012). White sharks commonly inhabit coastal and
continental shelf waters, although they have been observed entering
marine bays, estuaries, lagoons, and harbors (Compagno et al., 1997).
Recent studies suggest that these sharks also spend considerable amount
of time in open ocean habitats thousands of kilometers from shore
(Domeier, 2012). Areas likely to attract adult white sharks include
coastal waters adjacent to pinniped colonies or haulout sites, as these
are favored prey species (Klimley et al., 1996; Hussey et al., 2012).
Known prey of white sharks also includes a wide range of other species
from smaller demersal fish, such as rockfish, to giant pelagic species,
such as tuna and swordfish, as well as sea turtles, seabirds,
cetaceans, and other species of sharks (Fergusson, 1996; Long and
Jones, 1996; Wilson and Patyten, 2008; IUCN, 2009; Santana-Morales et
al., 2012). White sharks are recognized as apex predators throughout
the oceanic and coastal marine environments where they occur, and may
play an important role in ecosystem balance and population control for
a number of other marine species (Myers et al., 2007; Wilson and
Patyten, 2008). White sharks demonstrate the ability to undertake
transoceanic migrations to specific locations in patterns that appear
to be predictable (Boustany et al., 2002; Jorgensen et al., 2010;
Chapple et al., 2011; Domeier, 2012).
Great white sharks are distinguished by their stout spindle-shaped
body, moderately long and bluntly conical snout, five long gill slits,
large falcate first dorsal fin with free rear tip located over the
pectoral inner margins, pivoting second dorsal and anal fins, white
ventral body color, and lack of any secondary keels on the base of the
caudal fin. The teeth are large, flat, and triangular shaped, with
blade-like serrations, although teeth in the rear of the mouth get progressively smaller and sometimes lack serration,
especially in younger sharks (Compagno et al., 1997; FAO, 2012). The
maximum size of this species has not been established, but has been
estimated at about 6 m (19 ft), and possibly up to 6.4 m (21 ft), or
more (Cailliet et al., 1985; Wilson and Patyten, 2008; IUCN, 2009).
Estimated weight of the largest individuals is nearly 3,000 kg (6,600
lbs) (Cailliet et al., 1985; Anderson et al., 2011).
Available information on the general life history pattern of white
sharks suggests that females mature at about 12-14 years of age, and
about 4-5 m (13-16 ft) in length. Males mature at 9-10 years old, and
about 3.5-4.1 m (11.5-13.5 ft) in length (Compagno et al., 1997). It is
believed that females give birth at 2 or 3-year intervals to litters of
2-10 pups that are 1-1.5 m (3.3-4.9 ft) in length after a 12-22 month
gestation (Francis, 1996; Wilson and Patyten, 2008; Domeier, 2012).
Embryos are oophagus, meaning they consume and store yolk in their
stomachs (Francis, 1996; Uchida et al., 1996), and viviparous (live)
birth of pups likely occurs sometime between May and October (Domeier,
2012). Specific knowledge of pup survival rates is not available, but
is estimated to be low (CITES, 2004).
Primary concentrations of white sharks occur in South Africa,
Australia and New Zealand, and the northeastern Pacific Ocean, with
other white sharks observed in the north Atlantic and the Mediterranean
(Boustany et al., 2002; Domeier and Nasby-Lucas, 2006; Weng et al.,
2007; Jorgensen et al., 2010). Genetic and migration studies provide
evidence that these may represent separate populations (Jorgensen et
al., 2010). Mitochondrial DNA suggests at least three matrilineal
populations: South Africa/northwest Atlantic; southwest Pacific; and
northeastern Pacific (Gubili et al., 2012). Although the southwestern
Pacific and northeastern Pacific populations could potentially
interbreed, the genetic sampling indicates that these two populations
are largely reproductively isolated. It has been suggested that the
northeastern Pacific population was founded by relatively few sharks
within the last 200,000 years, and hasn't mixed with other shark
populations near Australia or South Africa since (Hance, 2009;
Jorgensen et al., 2010).
White sharks in the northeastern Pacific Ocean have been observed
from Baja California to the Bering Sea (Kato, 1965; COSEWIC, 2006) and
offshore out to Hawaii. Using satellite and acoustic telemetry,
researchers have followed movements of white sharks in the northeastern
Pacific Ocean and discovered patterns of site fidelity and repeated
homing in structured seasonal migrations, including fixed destinations,
schedules, and routes (Boustany et al., 2002; Jorgensen et al., 2010).
As a result, three core areas have been identified in the central and
northeastern Pacific: (1) North American shelf waters; (2) slope and
offshore waters of Hawaii; and (3) an area between the North American
coast and Hawaii termed the ``white shark caf[eacute]'' or Shared
Offshore Foraging Area (SOFA) (Jorgensen et al., 2010; Anderson et al.,
2011; Domeier, 2012). Each winter, great white sharks leave coastal
aggregation sites off of central California (Farallon Islands/
A[ntilde]o Nuevo/Point Reyes) and migrate 2000-5000 km offshore to
subtropical and tropical pelagic habitats, returning to coastal
aggregation sites in late summer. Site fidelity in North American
coastal hotspots has also been documented using photo-identification
(Jorgensen et al., 2010; Chapple et al., 2011; Sosa-Nishizaki et al.,
2012). Guadalupe Island, located 250 miles off the coast of Baja
California, Mexico, is also a preferred aggregation site for adults
(Sosa-Nishizaki et al., 2012). Adult males annually migrate from
preferred aggregation sites to the SOFA/white shark caf[eacute].
Females have been observed to migrate biennially between preferred
aggregation sites and the area surrounding the SOFA/white shark
caf[eacute], usually after males have returned to coastal aggregation
sites (Domeier, 2012).
The coastal areas of southern California and Baja California,
Mexico, appear to be important nursery areas hosting large
concentrations of young-of-the-year (YOY) and juvenile great white
sharks (Dewar et al. 2004; Weng et al., 2007; Galv[aacute]n-
Maga[ntilde]a et al., 2011; Domeier, 2012; Santana-Morales et al.,
2012). Information gained from the records of white shark bycatch in
California and Baja fisheries, including gillnet, seine-net, and hook
and line fisheries (Lowe et al., 2012; Santana-Morales et al., 2012),
along with relatively consistent reporting of juvenile white shark
observations along the southern California coast, lend support to the
assertion that this area is important developmental habitat for white
sharks before they mature into larger adults. Estimates of abundance
have not been available historically, but recent studies have suggested
the population size at two known aggregation sites (Farallon Islands/
Central California and Guadalupe Island) in the northeastern Pacific
Ocean is around 340 sub-adults and adults (Chapple et al., 2011; Sosa-
Nishizaki et al., 2012).
Analysis of the Petitions and Information Readily Available in NMFS Files
The two petitions request the same action, to list the northeastern
Pacific Ocean (NEP) DPS of great white shark (or white shark) as
endangered or threatened under the ESA and to designate critical
habitat for the DPS. Therefore, we evaluated the information provided
in both petitions and readily available in our files to determine if
the petitions presented substantial scientific or commercial
information indicating that the petitioned action may be warranted.
Both petitions contain information on the species, including the
taxonomy, species description, geographic distribution, habitat,
population status and trends, and factors contributing to the species'
decline. Both petitions state that a primary threat to the NEP
population of white shark is exploitation by fishing (historical and
current) and bycatch in fisheries. Both petitions also assert that the
lack of adequate regulatory protection worldwide, bioaccumulation of
contaminants, and habitat degradation, as well as the species'
biological constraints, increase the susceptibility of the NEP
population of white shark to extinction.
According to both petitions, the NEP population of white shark
qualifies as a DPS because the NEP population is both discrete and
significant, as defined under the Services' DPS policy (61 FR 4722;
February 7, 1996). The WildEarth Guardians petition asserts that all of
the five causal factors in section 4(a)(1) of the ESA are adversely
affecting the continued existence of the NEP population, whereas the
Oceana et al. petition does not discuss disease and predation as a
factor that is adversely affecting the NEP population. In the following
sections, we analyze the information presented by the petitions and in
our files on the qualification of the NEP population of white shark as
a DPS and the specific ESA section 4(a)(1) factors affecting the
population's risk of extinction.
Qualification of Northeastern Pacific Ocean Population as a DPS
Both petitions assert that the NEP population of white shark
qualifies as a DPS, because it is both a discrete and significant
population segment of the species, as defined in the NMFS and USFWS
policy on DPSs (61 FR 4722; February 7, 1996). First, the petitions
state that the NEP population is discrete based on both genetic and
spatial separation from other populations of white shark. Genetic analyses
indicate that the NEP population of white sharks is similar to and
descended from the Australian/New Zealand (ANZ) population (Jorgensen
et al., 2010; Gubili et al., 2012). The NEP population was likely
established during the Late Pleistocene, from a limited number of
founders from the ANZ population, but has since had little gene flow
with the ANZ population (Jorgensen et al., 2010). Thus, although the
two populations can interbreed, they are thought to be largely
reproductively isolated (Jorgensen et al., 2010).
In addition to genetic separation, the NEP population is
geographically separated from other populations, adheres to predictable
seasonal migratory routes, and exhibits strong site fidelity within the
NEP. As discussed above, white sharks in the NEP population range from
Baja California to the Bering Sea, and out to Hawaii. Tagged white
sharks from the NEP population consistently used three core areas
within the northeastern and central Pacific ocean: (a) The coastal
shelf waters of North America (primarily from central California to
Baja California); (b) the slope and offshore waters of the Hawaiian
archipelago; and (c) offshore waters between California and Hawaii,
including an offshore habitat approximately halfway between California
and Hawaii referred to as the SOFA/white shark caf[eacute], used
primarily by adults (Boustany et al., 2002; Jorgensen et al., 2010;
Domeier, 2012). The individuals followed seasonal migratory patterns,
generally moving offshore starting in winter and returning to the
California and Baja California coast in the late summer (Jorgensen et
al., 2010; Domeier, 2012). Tagged individuals from the NEP population
did not show any straying or spatial overlap with the ANZ population
(Jorgensen et al., 2010). YOY and juvenile white sharks also stay
within the geographic boundaries of the NEP population, likely using
nearshore, shallow waters of the Southern California Bight and Baja
California as nursery habitats, with adults likely aggregating at sites
off central California and at Guadalupe Island (off Baja California) to
mate (Domeier, 2012). Thus, the available information on migratory
behavior and habitat use indicates that the NEP population is
geographically separated from other white shark populations.
Second, the petitions state that the NEP population is discrete
because of international governmental boundaries within which
differences in control of exploitation, management of habitat,
conservation status, or regulatory mechanisms exist that are
significant in light of section 4(a)(1)(D) of the ESA (i.e., the
inadequacy of existing regulatory mechanisms as a factor to consider in
determining whether a species is endangered or threatened). The
petitions state that a large portion of the NEP population's habitat is
within U.S. waters, highlighting the importance of U.S. protections for
the species. The petitions also argue that the NEP population is
discrete because it ranges internationally into waters with differing
management regimes, particularly when occupying offshore habitats and
visiting aggregation sites off Baja California, where it may be subject
to exploitation by non-U.S. entities. However, the Services' DPS policy
states that a population may be considered discrete if it is separated
from other populations by international boundaries within which
significant differences in regulatory mechanisms exist. That the NEP
population crosses these international boundaries actually argues
against considering this population as discrete from other white shark
populations. Thus, the NEP population is not considered discrete based
on this factor. Nevertheless, the information available in the
petitions and in our files provides evidence suggesting the NEP
population may be discrete based on both genetic and spatial separation
from other populations.
Both petitions make the case that the NEP population is significant
to the taxon. As described above, the NEP population does not appear to
overlap spatially with other populations (Jorgensen et al., 2010;
Domeier, 2012; Gubili et al., 2012). The petitions reason that loss of
this population would result in a significant gap in the range of the
species because it is unlikely, given the geographic separation of the
NEP population from other populations, that sharks from other
populations would expand their distribution into the NEP's current
habitats. The petitions also state that the NEP population is
genetically differentiated from other white shark populations, as
described above. In addition, the Oceana et al. petition contends that
the NEP population occupies an ecological setting that is unique to
this species, because they are the only population to occupy coastal
waters off California and the SOFA. Overall, the information available
in the petitions and in our files suggests that the NEP population of
white shark may be significant to the species. The Oceana et al.
petition also argues that great white sharks play an important
ecological role that is essential for the health of the NEP ecosystem,
as a top predator that regulates prey populations (e.g., fish, other
sharks, and pinnipeds). We do not comment on the merit of this
statement, but note that in determining whether a discrete population
segment is significant, the NMFS and USFWS policy focuses on the
biological and ecological significance of the population segment to the
taxon, not to the ecosystem.
Based on the above analysis, we conclude that the information in
the two petitions and in our files suggests that the NEP population of
white shark may qualify as a DPS under the discreteness and
significance requirements.
The Present or Threatened Destruction, Modification, or Curtailment of the Species' Habitat or Range
Both petitions assert that habitat degradation, largely associated
with increasing human activity, poses a threat to the NEP population of
white shark, although the two petitions focus on different sources of
habitat degradation. The Oceana et al. petition briefly mentions that
pollutant discharge can degrade coastal aggregation and nursery
habitats, whereas the WildEarth Guardians petition goes into more
detail on this potential threat. The WildEarth Guardians petition cites
urban stormwater runoff and point source discharge as important sources
of pollutants (e.g., pesticides, fertilizers, trace metals, synthetic
organic compounds, petroleum, and pathogens) into the Southern
California Bight (DiGiacomo et al., 2004). The petition states that
these pollutants threaten predators like white sharks, primarily
through effects on their prey. For example, historical discharges of
organochlorines, such as DDT and PCBs, into the Southern California
Bight have resulted in high levels of these contaminants in local
populations of pinnipeds (Blasius and Goodmanlowe, 2008), one of the
prey resources for white sharks. Both petitions cite a recent finding
that young white sharks sampled off California have high levels of
mercury, DDT, PCBs, and chlordanes that could result in physiological
impairment (Mull et al., 2012). The WildEarth Guardians petition
briefly states that water quality in areas off Mexico where the NEP
population occurs may also be affected by contaminants (Parks Watch,
2004).
The WildEarth Guardians petition also suggests that the
concentration of marine debris in the North Pacific Gyre (the ``Great
Pacific Garbage Patch'') mayhave deleterious effects on offshore habitats, including the SOFA. The
main concern expressed in the petition is the concentration of plastic
of various sizes in the ``Garbage Patch'' (Algalita, 2009) which could
be ingested by white sharks in the area either directly or ingested by
their prey. The petition also suggests that accumulation of persistent
organic pollutants on the plastic (Algalita, 2009) may pose another
threat to the health of white sharks. We note, however, that it appears
to be unclear exactly what the adults (primarily males) are preying on
in the SOFA (Jorgensen et al., 2010; Domeier, 2012) because the area is
devoid of the small marine mammals typically preyed upon by adult white
sharks (Domeier, 2012). Adults in the SOFA may be feeding on squid or
other species that target squid (Domeier, 2012). Without specific
information about the extent to which adults in the SOFA are feeding
and what they are feeding on, it is difficult to evaluate the potential
effects of plastic marine debris on the NEP population's feeding
habitat and prey resources.
The Oceana et al. petition focuses on two sources of habitat
degradation: (1) Decreased prey resources due to human exploitation;
and (2) the effects of ocean acidification on the California Current
ecosystem. The WildEarth Guardians petition briefly mentions that
fisheries activities in coastal areas may deplete important prey
resources for the NEP population (CITES, 2004). The Oceana et al.
petition provides more detail, stating that human exploitation depleted
populations of pinnipeds, an important prey resource for adult white
sharks. The petition contends that although pinniped populations are
currently increasing, they were depleted for a long period of time and
remain below historical levels. We note that the most recent stock
assessments estimate that harbor seals may be at carrying capacity
(NMFS, 2011a) and that northern elephant seals have almost reached
their carrying capacity for pups per year (NMFS, 2007). Population
trends have generally been increasing since the 1980s or earlier for
harbor seals, California sea lions, and northern elephant seals in
California (NMFS, 2007; 2011a; 2011b). Thus, although these prey
resources may have been limited in the past when pinniped populations
were at historical lows, the populations have been increasing over the
last 30 years or more and may not currently be limiting. For example,
an increased frequency of observed shark attacks on prey off the South
Farallon Islands from 1983 to 1993 indicated a potential increase in
the white shark population at the islands, which may be explained by
increased recruitment of younger white sharks supported by the increase
and stabilization of pinniped prey resources over the 1970s and 1980s
(Pyle et al., 1996). Further analysis is needed to evaluate what effect
changes in pinniped populations have had on the status of white shark
populations over time. The petition also states that there have been
and continue to be major commercial fisheries for most of the other
prey resources supporting various life stages of white sharks (e.g.,
fish species, crustaceans, cephalopods; Klimley, 1985; Ellis and
McCosker, 1995). Again, further analysis is needed to specifically
evaluate the impacts of these fisheries on prey resources for white
sharks.
The Oceana et al. petition also contends that the effects of ocean
acidification could have negative impacts on the marine food web within
the California Current ecosystem, including on the NEP population of
white shark. The petition cites a model simulation study which predicts
that by 2050, the oceanic uptake of increased atmospheric
CO2 will lower the pH and the saturation state of aragonite
(a mineral form of calcium carbonate, used by calcifying organisms) in
nearshore waters of the California Current system to levels well below
the natural range for this area (Gruber et al., 2012). The petition
states that these effects of ocean acidification will have negative
impacts on fish species, referencing recent studies showing that high
CO2 and low pH levels impair olfactory responses and homing
ability in clownfish (Munday et al., 2009) and can lead to cardiac
failure in some fish species (Ishimatsu et al., 2004). The petition
readily admits, however, that the severity of effects on specific
species is uncertain. Some fish species may experience metabolic
responses to elevated CO2 levels at the cellular level, but
are able to compensate for those responses at the whole animal level,
making them less sensitive to the effects of ocean acidification
(Portner, 2008). In addition, extrapolating specific effects at the
species levels to the overall ecosystem (e.g., effects on prey
availability and predator-prey interactions for top predators like
white sharks) is highly uncertain. The petition also states that ocean
acidification can potentially affect marine mammals and other marine
life by reducing the sound absorption of seawater and allowing sound to
travel further (Hester et al., 2008). However, the petition does not
explain what the potential effects on marine mammals and other marine
life may be or how any such effects relate to the degradation of white
shark habitat (e.g., the availability or abundance of prey resources).
The available information is not sufficient to determine if ocean
acidification may be threatening the habitat of the NEP population of
white shark such that listing may be warranted.
We conclude that the information in the petitions and in our files
suggests that habitat degradation associated with pollutant discharge
in the Southern California Bight may be impacting the health of the NEP
population of white shark. Human exploitation may have impacted prey
resources (e.g., pinnipeds and fish and invertebrate species) in the
past; however, further analyses are needed to evaluate the recent and
current impacts on prey resources. In addition, the information
provided on the effects of marine debris in the North Pacific Gyre or
ocean acidification is insufficient to evaluate whether these factors
may be threatening the habitat of the NEP population of white shark
such that listing may be warranted.
Overutilization for Commercial, Recreational, Scientific, or Educational Purposes
Information from both petitions suggests that a primary threat to
the NEP population of white shark is from fisheries. The petitions cite
information on the effects of fisheries on white sharks worldwide and
within the NEP. White sharks are harvested in targeted fisheries and as
bycatch and are highly prized for their teeth, jaws, and fins. White
sharks are primarily caught incidentally in commercial fisheries using
longlines, setlines, gillnets, trawls, fish traps, and other gear
(Compagno, 2001; Fowler et al., 2005; Lowe et al., 2012; Santana-
Morales et al., 2012). The curious nature of white sharks makes them
more vulnerable to incidental capture, and their high value and
negative reputation may contribute to the killing of incidentally
caught individuals rather than being released alive (Fowler et al.,
2005). CITES (2004a) estimated that low to mid hundreds of white sharks
are killed annually as bycatch within each major region of the species'
range. Targeted sport and commercial fisheries for white sharks also
exist worldwide. Targeted sports fisheries may either kill or release
sharks alive, but post-release mortality is unknown. It is estimated
that tens to low hundreds of white sharks are killed in sports
fisheries worldwide each year (CITES, 2004). Targeted commercial
fisheries for white sharks are thought to be uncommon and opportunistic
when aggregations are found, but the species' site fidelity and tendency to
aggregate in predictable areas make it vulnerable to over-exploitation
(CITES, 2004). Targeted commercial fisheries worldwide may also kill
tens to low hundreds of white sharks each year (CITES, 2004).
In the NEP Ocean, there is little commercial fishing activity in
the SOFA, providing a potential refuge from incidental capture for
individuals when they occupy this offshore area (Domeier, 2012).
However, the lack of international laws to protect great white sharks
in international waters is a potential threat to the species (Domeier,
2012; discussed further under ``Inadequacy of existing regulatory
mechanisms''). White sharks are most vulnerable to fisheries capture
when occupying nearshore aggregation or nursery habitats, especially
YOY and juvenile stages (Domeier, 2012). Off California, there have
been no directed fisheries for white sharks, but incidental and
targeted catch has occurred (Lowe et al., 2012). An analysis of
fishery-dependent catch records for the Southern California Bight from
1936 to 2009 found that the majority of the reported white shark
captures (where size was indicated) were of YOY sharks (60 percent),
followed by juveniles (32 percent) and subadults/adults (8 percent);
however, the proportion of YOY sharks in the reported catch increased
to 77 percent after the nearshore gillnet ban was implemented in 1994
(Lowe et al., 2012). Commercial entangling nets (81 percent) and
recreational hook-and-line fishing (8 percent) accounted for the
majority of the reported white shark captures (Lowe et al., 2012). The
number of reported white shark captures in commercial entangling nets
has been 20 or less from 1985 through 2009, except in 1985 when 25
captures were reported (Lowe et al., 2012). The analysis suggests that
the effects of incidental capture in gillnet fisheries off California
have decreased compared to historical effects. As gillnet fishing
effort decreased from the mid-1980s to mid-1990s, so did reports of
white shark captures (Lowe et al., 2012). However, although gillnet
fishing effort remained stable or decreased from the mid-1990s through
2009, reports of white shark captures increased from 2005 through 2009
(Lowe et al., 2012). Increases in the number of reported captures in
the gillnet fisheries since 2005, despite stable or decreased effort,
may be the result of increased reporting of captures and/or an increase
in the abundance of white sharks due to the nearshore gillnet ban and
changes in offshore gillnet regulations (Lowe et al., 2012). Also, data
from the Monterey Bay Aquarium's Juvenile White Shark Tagging Program
indicate that YOY and juvenile white sharks have relatively high post-
release survival after being caught in gillnet gear (Lowe et al.,
2012).
Incidental catch of white sharks also continues to occur off Baja
California. Incidental catch of 111 great white sharks was reported
from 1999 through 2010, consisting of YOY (79.8 percent) and juvenile
(20.2 percent) sharks (Santana-Morales et al., 2012). Incidental catch
primarily occurred in bottom gillnet gear (74.7 percent), but also in
drift gillnet (18 percent) and artisanal seine net (4.5 percent) gear
(Santana-Morales et al., 2012).
The petitions assert that the continued incidental catch of white
sharks poses a threat to the species, because the removal of just a few
individuals could have a substantive effect on the local population
(Pyle et al., 1996; Chapple, 2011). The petitions also highlight the
high value of white shark teeth, jaws, and fins as trophies, curios,
and food, stating that this provides a strong monetary incentive to
capture and keep white sharks (Clarke, 2004; Shivji et al., 2005;
Clarke et al., 2006).
We conclude that the petitions and information in our files present
evidence that fisheries impacts continue to affect white shark
populations worldwide and in the NEP, primarily due to incidental
capture in fisheries and the potential for the high value of great
white shark teeth, jaws, and fins to promote keeping incidentally
caught individuals rather than releasing them back into the water. This
information suggests that fisheries impacts may be affecting the
continued existence of the NEP population of white shark. To further
evaluate these effects, more information is needed on fisheries impacts
specifically within the range of the NEP population, particularly on
the capture of white sharks in fisheries in offshore waters and the
lethal and sublethal effects of catch and release.
Disease or Predation
The WildEarth Guardians petition asserts that the addition of
mercury, organochlorine contaminants, and other pollutants to the ocean
and the effects of these pollutants on the NEP population of white
sharks may be categorized as disease. The petition does not provide any
additional information to support that disease is a factor affecting
the NEP population's continued existence such that listing may be
warranted. Thus, the available information is insufficient to evaluate
if disease may be affecting the continued existence of the NEP
population of white shark. The petition more appropriately discusses
pollutants and their effects on the NEP population under the habitat
degradation and ``other natural or manmade'' factors.
Inadequacy of Existing Regulatory Mechanisms
The petitions assert that the inadequacy of existing Federal,
state, or international regulatory mechanisms require that the NEP
population of white shark be listed under the ESA. The petitions
contend that although Federal, state, and international regulations
exist to protect white sharks from targeted capture in some areas,
these regulations are insufficient because white sharks in the NEP
population are still vulnerable to incidental capture throughout its
range, and to exploitation when in international waters. In addition,
the WildEarth Guardians petition states that existing regulations do
not protect the NEP population's habitat and health from threats such
as habitat degradation, pollution, and overfishing of prey resources.
Within the United States, Federal and state regulations to protect
white sharks vary. Currently, the retention of white sharks in U.S.
Federal waters in the Pacific Ocean is prohibited under the Highly
Migratory Species Fishery Management Plan. In California, targeted
capture of white sharks is prohibited, but incidentally caught white
sharks may be retained under a permit from the California Department of
Fish and Game for scientific or educational purposes (14 CCR Sec.
28.06). In Oregon, all white sharks must be released immediately if
caught (ODFW, 2012). Washington and Hawaii do not have specific
fisheries regulations for white shark. However, both Hawaii and
California passed bans making it unlawful to possess, sell, offer for
sale, trade, or distribute shark fins, which may provide some
protection for white sharks. The petitions argue that despite these
protections, the continued incidental capture and mortality of even
small numbers of white sharks in U.S. waters, particularly off
California, can have a large impact on the local population, citing a
study off the Farallon Islands in which the removal of four white
sharks from the area in 1982 resulted in significantly fewer sightings
of shark attacks on pinnipeds than expected in 1983 to 1985 (Pyle et
al., 1996). The petitions also suggest that illegal fishing may be a
problem in the United States, citing cases of illegal fishing and sale of white shark teeth, jaws, and fins in 2003 (CITES,
2004).
Outside of the United States, protections for white sharks also
vary. In Mexico, catch and retention of white sharks and the landing of
shark fins without carcasses has been banned since 2006 (Lack and Sant,
2011), although incidental capture continues to occur (Galv[aacute]n-
Maga[ntilde]a et al., 2010; Santana-Morales et al., 2012). In Canada,
there are no specific regulations to protect white sharks, although a
ban on shark finning may provide some protection (DFO, 2007). In
international waters, white sharks are protected under CITES (Appendix
II) and other international agreements, including the Convention on
Migratory Species (Appendix I and II) and the United Nations Convention
on the Law of the Sea. However, the petitions contend that these
protections are not sufficient, given continued trade in white shark
products due to poaching and variable enforcement of regulations
(CITES, 2004; Clarke, 2004; Shivji et al., 2005; Clarke et al., 2006;
Galv[aacute]n-Maga[ntilde]a et al., 2010; Jorgensen et al., 2010;
Viegas, 2011).
Based on the information in the petition and in our files as
discussed above, we conclude that existing regulatory mechanisms may be
inadequate to address threats to the NEP population of white shark. To
further evaluate the adequacy of existing regulatory mechanisms, more
information is needed regarding the level of illegal fishing and
poaching in U.S. and international waters.
Other Natural or Manmade Factors
The two petitions assert that other natural or manmade factors may
be affecting the survival and recovery of the NEP population of white
shark, including contaminant loads, negative press, life history
factors, small population size, and the synergistic effects of all of
the threats facing the population. Both petitions cite a study
conducted in the Southern California Bight revealing mercury and
organochlorines (e.g., DDT, PCBs, and chlordanes) in the tissues of
juvenile white sharks at levels that may result in physiological
impairment (Mull et al., 2012). Young white sharks are likely
bioaccumulating these contaminants (likely from historical discharges
in the Southern California Bight) when feeding on prey resources in the
area (Blasius and Goodmanlowe, 2008; Mull et al., 2012). The WildEarth
Guardian petition also cites negative media attention as a threat to
white sharks, especially when shark attacks on humans occur, because
this generates general paranoia and encourages targeting of the species
for sport or trophy hunting (IUCN, 2009).
The WildEarth Guardians petition asserts that natural factors,
including the species' life history characteristics and small
population size, also increase the extinction risk of the NEP
population of white shark, particularly when considered in combination
with other threats to the species. The petition states that the
species' life history characteristics (e.g., slow growth, late
maturation, long-life, long generation time, small litter size, and low
reproductive capacity) make it susceptible to extinction when faced
with population declines and continuing threats (Withgott and Brennan,
2007). The petition also contends that the small estimated population
size (e.g., approximately 340 subadults and adults in the NEP
population; Chapple et al., 2011; Sosa-Nishizaki et al., 2012) makes
the population highly susceptible to extinction due to a stochastic
event (Brook et al., 2008). We note, however, that this estimate of
abundance is based on studies of individuals surveyed in aggregation
sites off central California and Guadalupe Island, and do not include
YOY and juveniles. Also, without information on the historical
abundance of the NEP population, it is difficult to assess what this
estimated population size means for the persistence of the population.
The low estimated abundance of the population may be the result of
anthropogenic pressures on the population or a naturally low carrying
capacity (the NEP population is thought to have been established by a
limited number of founders from the ANZ population; Jorgensen et al.,
2010) (Chapple et al., 2011). Catch ratios of white sharks to all shark
species off the U.S. west coast from 1965 (1:67) to 1983 (1:210)
suggest a potential decline in abundance (Casey and Pratt, 1985, cited
in Fowler et al., 2005). However, recent increases in the incidental
capture of white sharks in gillnet fisheries off California, despite
stable or decreasing fishing effort, suggest that the population may be
increasing (Lowe et al., 2012). In addition, an increased frequency of
observed white shark attacks on pinnipeds off the South Farallon
Islands over time indicates an increase in the shark population at the
islands (Pyle et al., 1996; Pyle et al., 2003). Thus, it is difficult
at this time to determine population trends and to evaluate how the
estimated size of the NEP population relates to the population's
extinction risk.
Overall, the petition and information in our files suggest that
effects from bioaccumulation of contaminants and negative media
attention, coupled with the life history characteristics of white
sharks, may be affecting the survival and recovery of the NEP
population. More specific information is needed, however, to assess
population trends and to evaluate the population's estimated abundance
in terms of the potential effects on the population's survival and
recovery.
Summary of Section 4(a)(1) Factors
We conclude that the petition presents substantial scientific or
commercial information indicating that multiple section 4(a)(1)
factors, as discussed above, may be causing or contributing to an
increased risk of extinction for the NEP population of white shark.
Petition Finding
After reviewing the information contained in both petitions, as
well as information readily available in our files, we conclude the
petitions present substantial scientific information indicating the
petitioned action of listing the NEP population of white shark as a
threatened or endangered DPS may be warranted. Therefore, in accordance
with section 4(b)(3)(A) of the ESA and NMFS' implementing regulations
(50 CFR 424.14(b)(3)), we will commence a status review of the species.
During the status review, we will determine whether the population
identified by the petitioners meets the DPS policy's criteria, and if
so, whether the population is in danger of extinction (endangered) or
likely to become so within the foreseeable future (threatened)
throughout all or a significant portion of its range. We now initiate
this review, and thus, the northeastern Pacific Ocean population of
white shark is considered to be a candidate species (50 CFR 424.15(b)).
Within 12 months of the receipt of the WildEarth Guardians petition
(June 25, 2013), we will make a finding as to whether listing the
species as endangered or threatened is warranted as required by section
4(b)(3)(B) of the ESA. If listing the species is warranted, we will
publish a proposed rule and solicit public comments before developing
and publishing a final rule.
Information Solicited
To ensure that the status review is based on the best available
scientific and commercial data, we are soliciting information relevant
to whether the NEP Ocean population of white sharks is a DPS and
whether it is threatened or endangered. Specifically, we are soliciting
published and unpublished information in the following areas: (1) Population structure
information in the Pacific Ocean, such as genetics data; particularly
any unpublished information; (2) migratory and behavior patterns in the
NEP Ocean, particularly any unpublished information; (3) life history
and ecology, particularly any unpublished information; (4) historical
and current distribution and abundance of this species throughout the
NEP Ocean; (5) historical and current population trends in the NEP
Ocean; (6) historical and current data on commercial and recreational
fisheries directed at white sharks in the NEP Ocean, including Mexican
waters; (7) historical and current data on white shark bycatch and
retention in commercial and recreational fisheries in the NEP Ocean,
including Mexican waters; (8) data on the trade of white shark
products, including fins, jaws, and teeth in the NEP Ocean, including
Mexico; (9) data or other information on encounter rates with white
sharks through ecotourism operations and sightings data, and long-term
records of white shark attacks, wounds or scaring of marine mammals;
(10) adverse impacts related to coastal habitat degradation and the
health of white sharks, including, but not limited to, impacts related
to discharge of pollutants, marine debris, or ocean acidification; (11)
any current or planned activities that may adversely impact the
species; (12) ongoing or planned efforts to protect and restore the
species and their habitats; and (12) management, regulatory, and
enforcement information.
We also request information on critical habitat for the NEP Ocean
population of white sharks. Specifically, we request information on the
physical and biological habitat features that are essential to the
conservation of the species and identification of habitat areas that
include these essential physical and biological features. Essential
features include, but are not limited to: (1) Space for individual and
population growth and for normal behavior; (2) food, water, air, light,
minerals, or other nutritional or physiological requirements; (3) cover
or shelter; (4) sites for reproduction and development of offspring;
and (5) habitats that are protected from disturbance or are
representative of the historical, geographical, and ecological
distributions of the species (50 CFR 424.12). For habitat areas
potentially qualifying as critical habitat, we request information
describing: (1) The activities that affect the habitat areas or could
be affected by the designation; and (2) the economic impacts, impacts
to national security, or other relevant impacts of additional
requirements of management measures likely to result from the
designation.
We request that all information be accompanied by: (1) Supporting
documentation such as maps, raw data with associated documentation,
bibliographic references, or reprints of pertinent publications; and
(2) the submitter's name, mailing address, email address, and any
association, institution, or business that the person represents.