[Federal Register Volume 80, Number 41 (Tuesday, March 3, 2015)]
[Proposed Rules]
[Pages 11379-11386]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-04409]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Parts 223 and 224

[Docket No. 141219999-5132-01]
RIN 0648-XD680


Endangered and Threatened Wildlife; 90-Day Finding on a Petition 
To List the Common Thresher Shark as Threatened or Endangered Under the 
Endangered Species Act

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

ACTION: Notice of 90-day petition finding, request for information, and 
initiation of status review.

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SUMMARY: We, NMFS, announce the 90-day finding for a petition to list 
the common thresher shark (Alopias vulpinus) as either endangered or 
threatened under the U.S. Endangered Species Act (ESA) either worldwide 
or as one or more distinct population segments (DPSs) identified by the 
petitioners. We find that the petition presents substantial scientific 
or commercial information indicating that the petitioned action may be 
warranted for the species worldwide. We find that the petition fails to 
present substantial scientific or commercial information to support the 
identification of DPSs of the common thresher suggested by the 
petitioners, and, as such, we find that the petitioned action of 
listing one or more of these DPSs is not warranted. Accordingly, we 
will initiate a review of the status of the common thresher shark at 
this time. To ensure that the status review is comprehensive, we are 
soliciting scientific and commercial information regarding this 
species.

DATES: Information and comments on the subject action must be received 
by May 4, 2015.

ADDRESSES: You may submit comments, information, or data, identified by 
``NOAA-NMFS-2015-0025'' by either of the following methods:
    <bullet> Electronic Submissions: Submit all electronic public 
comments via the Federal eRulemaking Portal. Go to www.regulations.gov/#!docketDetail;D=NOAA-NMFS-2015-0025. Click the ``Comment Now'' icon, 
complete the required fields, and enter or attach your comments.
    <bullet> Mail or hand-delivery: Office of Protected Resources, 
NMFS, 1315 East-West Highway, Silver Spring, MD 20910.
    Instructions: You must submit comments by one of the above methods 
to ensure that we receive, document, and consider them. Comments sent 
by any other method, to any other address or individual, or received 
after the end of the comment period, may not be considered. All 
comments received are a part of the public record and will generally be 
posted for public viewing on http://www.regulations.gov without change. 
All personal identifying information (e.g., name, address, etc.), 
confidential business information, or otherwise sensitive information 
submitted voluntarily by the sender will be publicly accessible. We 
will accept anonymous comments (enter ``N/A'' in the required fields if 
you wish to remain anonymous). Attachments to electronic comments will 
be accepted in Microsoft Word, Excel, or Adobe PDF file formats only.

FOR FURTHER INFORMATION CONTACT: Chelsey Young, NMFS, Office of 
Protected Resources (OPR), (301) 427-8491 or Marta Nammack, NMFS, OPR, 
(301) 427-8469.

SUPPLEMENTARY INFORMATION:

Background

    On August 26, 2014, we received a petition from Friends of Animals 
requesting that we list the common thresher shark (Alopias vulpinus) as 
endangered or threatened under the ESA, or, in the alternative, 
delineate six distinct population segments (DPSs) of the common 
thresher shark, as described in the petition, and list them as 
endangered or threatened. Friends of Animals also requested that 
critical habitat be designated for this species in U.S. waters 
concurrent with final ESA listing.
    The petitioner states that the common thresher shark merits listing 
as an endangered or threatened species under the ESA because of the 
following: (1) The species faces threats from historical and continued 
fishing for both commercial and recreational purposes; (2) life history 
characteristics and limited ability to recover from fishing pressure 
makes the species particularly vulnerable to overexploitation; and (3) 
there is a lack of regulations that specifically protect the common 
thresher shark.

ESA Statutory Provisions and Policy Considerations

    Section 4(b)(3)(A) of the ESA of 1973, as amended (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 promptly publish the 
finding in the Federal Register (16 U.S.C. 1533(b)(3)(A)). When we find 
that substantial scientific or commercial information in a petition and 
in our files 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, which includes 
conducting a comprehensive review of the best available scientific and 
commercial information. Within 12 months of receiving the petition, we 
must conclude the review with a finding as to whether, in fact, the 
petitioned

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action is warranted. Because the finding at the 12-month stage is based 
on a significantly more thorough review of the available information, a 
``may be warranted'' finding at the 90-day stage 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 subspecies and, for any vertebrate 
species, any DPS that interbreeds when mature (16 U.S.C. 1532(16)). A 
joint NMFS-U.S. Fish and Wildlife Service (USFWS) policy clarifies the 
agencies' interpretation of the phrase ``distinct population segment'' 
for the purposes of listing, delisting, and reclassifying a species 
under the ESA (``DPS Policy''; 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 
(ESA sections 3(6) and 3(20), respectively; 16 U.S.C. 1532(6) and 
(20)). Pursuant to the ESA and our implementing regulations, the 
determination of whether a species is threatened or endangered shall be 
based on any one or a combination of the following five section 4(a)(1) 
factors: The present or threatened destruction, modification, or 
curtailment of habitat or range; overutilization for commercial, 
recreational, scientific, or educational purposes; disease or 
predation; inadequacy of existing regulatory mechanisms; and any other 
natural or manmade factors affecting the species' existence (16 U.S.C. 
1533(a)(1), 50 CFR 424.11(c)).
    ESA-implementing regulations issued jointly by NMFS and USFWS (50 
CFR 424.14(b)) 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. When 
evaluating whether substantial information is contained in a petition, 
we 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)).
    At the 90-day stage, we evaluate the petitioner's 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 petitioner's 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 
that indicates 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 that it supports the petitioner's assertions. 
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 alone 
negates a positive 90-day finding, if a reasonable person would 
conclude that the unknown information itself 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 at issue faces 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 at 
issue (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 ESA 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 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 for 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 such classification alone may 
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.

Species Description

Distribution

    The common thresher shark (Alopias vulpinus) is a large highly 
migratory pelagic species of shark found throughout the world in 
temperate and tropical seas. In the North Atlantic, common thresher 
sharks occur from Newfoundland, Canada, to Cuba in the

[[Page 11381]]

west and from Norway and the British Isles to the African coast in the 
east (Gervelis, 2013). Landings along the South Atlantic coast of the 
United States and in the Gulf of Mexico are rare. Common thresher 
sharks also occur along the Atlantic coast of South America from 
Venezuela to southern Argentina. In the eastern Atlantic, A. vulpinus 
ranges from the central coast of Norway south to, and including, the 
Mediterranean Sea and down the African coast to the Ivory Coast. They 
appear to be most abundant along the Iberian coastline, particularly 
during spring and fall. Specimens have also been recorded at Cape 
Province, South Africa (Goldman, 2009). In the Indian Ocean, A. 
vulpinus is found along the east coast of Somalia, and in waters 
adjacent to the Maldive Islands and Chagos archipelago. They are also 
present off Australia (Tasmania to central Western Australia), Sumatra, 
Pakistan, India, Sri Lanka, Oman, Kenya, the northwestern coast of 
Madagascar and South Africa. A few specimens have been taken from 
southwest of the Chagos archipelago, the Gulf of Aden, and northwest 
Red Sea. In the western Pacific Ocean, the range of A. vulpinus 
includes southern Japan, Korea, China, parts of Australia and New 
Zealand. They are also present around several Pacific Islands, 
including New Caledonia, Society Islands, Fanning Islands and Hawaii. 
In the Northeast Pacific Ocean, the geographic range of common thresher 
sharks extends from Goose Bay, British Columbia, Canada to the Baja 
Peninsula, Mexico and out to about 200 miles from the coast (Goldman, 
2009). Additionally, they are found off Chile and records exist from 
Panama (Campagno, 1984).

Physical Characteristics

    The common thresher shark possesses an elongated upper caudal lobe 
almost equal to its body length, which is unique to this family. It has 
a moderately large eye, a broad head, short snout, narrow tipped 
pectoral fins, no grooves on the head above the gills, and lateral 
teeth without distinct cusplets. The origin of the pelvic fins is well 
behind the insertion of the first dorsal fin. While some of the above 
characteristics may be shared by other thresher shark species, 
diagnostic features separating this species from the other two thresher 
shark species (bigeye thresher, A. superciliosus, and pelagic thresher, 
A. pelagicus) are the presence of labial furrows, the origin of the 
second dorsal fin posterior to the end of the pelvic fin free rear tip, 
and the white color of the abdomen extending upward over the pectoral 
fin bases, and again rearward of the pelvic fins. In living specimens, 
dorsal coloration may vary from brown, blue slate, slate gray, blue 
gray, and dark lead to nearly black, with a metallic, often purplish, 
luster. The lower surface of the snout (forward of the nostrils) and 
pectoral fin bases are generally not white and may be the same color as 
the dorsal surface (Goldman, 2009).

Habitat

    Surveys of the common thresher shark from our Southwest Fisheries 
Science Center (SWFSC) demonstrate habitat separation between juveniles 
and adults (PMFC, 2003; Smith et al., 2008). Juveniles occupy 
relatively shallow water over the continental shelf, while adults are 
found in deeper water, but rarely range beyond 200 miles (321.87 km) 
from the coast (PMFC, 2003; Smith et al., 2008). Both adults and 
juveniles are associated with highly biologically productive waters, 
found in regions of upwelling or intense mixing.

Feeding Ecology

    Common thresher sharks feed at mid-trophic levels on small pelagic 
fish and squid. Given their more specialized diet compared to other 
local pelagic sharks, they are more likely to exert top-down effects on 
their prey, although this remains to be demonstrated. Based on studies 
at the SWFSC, the top six prey species, in order, are northern anchovy, 
Pacific sardine, Pacific hake, Pacific mackerel, jack mackerel, and 
market squid (Preti et al., 2001, 2004). Thresher sharks are unique, in 
that they use their tail in a whip-like fashion to disorient and 
incapacitate their prey (Oliver, 2013).

Life History

    The life span of the common thresher shark is estimated between 15 
and 50 years, although additional research to confirm this is necessary 
(Gervalis, 2013). Thresher sharks reach maturity at approximately 5 
years of age and at around 166 cm fork length for both sexes. They grow 
approximately 30 cm per year for the first 5 years of their lives 
(Gervalis, 2013; Smith et al., 2008). Maximum size has been estimated 
for thresher sharks along the U.S. West Coast at 550 cm (Gervalis, 
2013; Smith et al., 2008). Their mode of reproduction is aplacental 
ovoviviparous and oophagous, and a typical litter size is 2-4 pups, 
with gestation thought to be around 9 months (NMFS Common Thresher 
Shark Fact Sheet; PMFC, 2003; Smith et al., 2008). Pupping is thought 
to occur in the springtime, with mating thought to occur in the summer, 
and nursery grounds for pups are in shallow continental shelf waters 90 
m deep or less (NMFS Common Thresher Shark Fact Sheet).

Analysis of DPS Information

    The petition requests that we list the common thresher shark 
throughout its range, or list the species as six DPSs. The petitioner 
identifies six subpopulations that it believes may qualify for listing: 
Eastern Central Pacific, Indo-West Pacific, Northwest and Western 
Central Atlantic, Southwest Atlantic, Mediterranean, and Northeast 
Atlantic. To meet the definition of a DPS, a population must be both 
discrete from other populations of the species and significant to the 
species as a whole (61 FR 4722; February 7, 1996).
    The petition does not provide biological evidence to support the 
existence of the six ``subpopulations'' identified; however, the 
petition states that six subpopulations of the common thresher shark 
are discrete. The petition goes on to define this discreteness 
according to the second discreteness factor listed in the NMFS/USFWS 
joint DPS policy, where a population can be considered discrete if it 
``is delimited by international governmental boundaries within which 
differences in control of exploitation, management of habitat, 
conservation status, or regulatory mechanisms exist that are 
significant in light of section 4(a)(1)(D) of the Act.'' The petitioner 
maintains that the ``broad and varied spectrum of harvest control, 
habitat management, conservation status, and regulatory mechanisms'' 
addressing the species may qualify different ``subpopulations'' as 
discrete under this discreteness factor, asserting that, ``due to broad 
differences in regulation of their management and capture, the 
subpopulations of common thresher sharks should be considered 
sufficiently discrete for protection as DPSs under the ESA.''
    The petition does not propose any boundaries for the six suggested 
DPSs, nor does the petition describe in any detail the ways in which 
different management relating to international governmental boundaries 
may delineate the species into boundaries aligning with the six 
suggested DPSs. Specific gaps in management or intergovernmental 
boundaries are not described as they relate to any of the six proposed 
DPSs. We were also unable to find information to define the six 
subpopulations as discrete on biological grounds. In our files, only a 
single preliminary study was available to suggest population structure 
of the

[[Page 11382]]

common thresher shark. This study examined mitochondrial control region 
DNA, which demonstrated significant population structure between most 
pairwise comparisons, but the sample sizes were extremely low, and thus 
the results could not be interpreted with confidence. The data support 
separate Atlantic vs. Pacific populations (or at least female 
philopatry) (Trejo, 2005). However, based on the preliminary nature of 
these data, and low sample size throughout the study, these results 
cannot be relied upon to divide the common thresher shark into the six 
subpopulations proposed by the petition.
    Based on information in the petition and readily available in our 
files, we were unable to find evidence to support the discreteness of 
any of the six DPSs proposed. Because of this, arguments made by the 
petitioner describing the potential significance of any suggested DPS 
are irrelevant. Thus, we conclude that the petition provides 
insufficient evidence to identify any DPSs of the common thresher shark 
at this time.

Analysis of Petition and Information Readily Available in NMFS Files

    The following sections contain information found in the petition 
and readily available in our files to determine whether a reasonable 
person would conclude that an endangered or threatened listing may be 
warranted as a result of any of the factors listed under section 
4(a)(1) of the ESA.

Common Thresher Shark Status and Trends

    The petition does not provide a population abundance estimate for 
common thresher sharks, but points to its ``vulnerable'' status on the 
IUCN Red List, and quotes extensively from the Encyclopedia of Life, an 
online collaborative database intended for documenting information on 
all species of life. The petition asserts that a global decline of 
common thresher sharks has been caused mainly by commercial and 
recreational fishing (both direct harvest and bycatch), particularly 
during the 1970s and early 1980s. The petition references high 
commercial catch rates for common threshers along the U.S. West Coast 
during the 1980s, and declines in catch by the mid-1990s, indicative of 
overexploitation (Goldman et al., 2009). In the Northwest and Western 
Central Atlantic, the petition cites the Encyclopedia of Life for 
asserting 50-80 percent declines in common thresher shark abundance 
occurring from 1986-2005. The petition describes likely declines of 
common thresher sharks in the Mediterranean due to high fishing 
pressure. In the Northeast Atlantic, the petition describes variable 
landings prior to 2000 and a decline in landings since 2002 (ICES, 
2006). Finally, the petition points to increased interest in 
recreational fishing of the common thresher shark, with the potential 
for high post-release mortality. The petition does not provide 
information on estimates of abundance across the range of the species.
    Although historical overfishing of the common thresher shark led to 
serious declines in population abundance, particularly during the 
1980s, regulations since the early 1990s have contributed to trends of 
rebuilding of the species over the past two decades in some portions of 
its range, particularly in the Eastern Pacific Ocean (PFMC, 2011; NMFS 
Common Thresher Shark Fact Sheet). However, in other portions of the 
species' global range, declines due to overutilization (bycatch, 
recreation, and directed catch) may be ongoing, leading to declines in 
abundance. The threat of commercial fishing is discussed in more detail 
below (see ``Overutilization'').
    The last IUCN assessment of the common thresher shark was completed 
in 2009 and since then several estimates of global and subpopulation 
trends and status have been made. Perhaps most heavily studied have 
been common thresher sharks in the Eastern Pacific Ocean, where the 
shark has historically been most heavily fished. Commercial fishing of 
thresher sharks in the U.S. was eliminated by gill net regulations by 
1990, and within a decade, the population began to slowly rebuild to 
just below 50 percent of the initial subpopulation size (Camhi et al., 
2007). A preliminary examination of trends in the catch-per-unit-effort 
and total catch of common thresher sharks in this region is consistent 
with earlier conclusions that the population is increasing from its 
decline in the late 1980s and early 1990s (PMFC, 2011). Efforts to 
conduct a full stock assessment have been initiated by NMFS. Based on 
preliminary stock assessment results, there appears to be an initial 
period of decline from 1981 to 1986, followed by a gradual recovery of 
the stock. The index is highly variable after 2000, which is possibly 
due to regulatory and operational changes in the fishery (SWFSC, 
unpublished data).
    In the Northwest Atlantic, declines in relative abundance cited by 
the petitioner were derived from analyses of logbook data, reported in 
Cort[eacute]s (2007). This study reported a 63 percent decline of 
thresher sharks (on the genus level) based on logbook data, occurring 
between 1986 and 2006 (Cort[eacute]s, 2007). The observer index data 
from the same study shows an opposite trend in relative abundance, with 
a 28 percent increase of threshers in the Northwest Atlantic since 
1992. Logbook data over the same period (1992-2006) showed a 50 percent 
decline in thresher sharks. The logbook dataset is the largest 
available for the western North Atlantic Ocean, but the observer 
dataset is generally more reliable in terms of consistent 
identification and reporting. According to observer data, relative 
abundance of thresher sharks (again, only at the genus level) in the 
western North Atlantic Ocean appears to have stabilized or even be 
increasing since the late 1990s (Cort[eacute]s, 2007). A more recent 
analysis using logbook data between 1996 and 2005 provides some 
supporting evidence that the abundance of thresher sharks has 
stabilized over this time period (Baum, 2010). However, the conflicting 
evidence between logbook and observer data showing opposite trends in 
thresher shark abundance cannot be fully resolved at this time. Data 
are not available in the petition or in our own files to assess the 
trend in population abundance in this region since 2006, or to assess 
the trend specific to the common thresher shark. Because the logbook 
data from this region shows consistent evidence of a significant and 
continued decline in thresher sharks, we must consider this information 
in our 90-day determination.
    For the Northeast Atlantic, there are no population abundance 
estimates available, but data indicate that the species is taken in 
driftnets and gillnets. In the Mediterranean Sea, estimates show 
significant declines in thresher shark abundance during the past two 
decades, reflecting data up to 2006; according to historical data 
compiled using a generalized linear model, thresher sharks have 
declined between 96 and 99 percent in abundance and biomass in the 
Mediterranean Sea (Ferretti et al., 2008).
    In other areas of the world, estimates of thresher shark abundance 
are limited. For the Indo-West Pacific, little information is currently 
available on common thresher sharks. Although pelagic fishing effort in 
this region is high, with reported increases in recent years, the 
common thresher shark is more characteristic of cooler waters, and 
further information needs to be collected on records and catches of the 
species in this region (IUCN assessment, 2009).
    In conclusion, trends throughout the Eastern Pacific Ocean portion 
of the species' range suggest that the population there is rebuilding 
from

[[Page 11383]]

historical overexploitation. However, across the rest of its global 
range, we find evidence suggesting that population abundance of common 
thresher sharks has continued to decline or, as in the Northwest 
Atlantic Ocean, may be stable at a diminished abundance. While data are 
still limited with respect to population size and trends, we find the 
petition and our files sufficient in presenting substantial information 
on common thresher shark abundance, trends, or status to indicate that 
the petitioned action may be warranted.

ESA Section 4(a)(1) Factors

    The petition indicated three main categories of threats to the 
common thresher shark: Overutilization for commercial, recreational, 
scientific, or educational purposes; the inadequacy of existing 
regulatory mechanisms; and other natural or manmade factors affecting 
its continued existence. We discuss each of these below, as well as an 
additional evaluation of other 4(a)(1) factors based on information in 
the petition, and the information readily available in our files.

Present or Threatened Destruction, Modification or Curtailment of 
Habitat or Range

    The petition does not list threats to habitat as impacting the 
common thresher shark. In our files, we were also unable to find 
evidence that destruction, modification, or curtailment of habitat or 
range were negatively impacting the species. Supporting this 
conclusion, in our files, we found evidence demonstrating that habitat 
pollution has not resulted in high concentrations of pollutants in the 
bodies of common thresher sharks. For example, Suk et al. (2009) 
demonstrated that the level of mercury measured in the muscle of 
individual thresher sharks was quite low (mean 0.13 <plus-minus> 0.15 
[mu]g/g), with no traces of mercury detected in the liver. Mercury 
concentration increased with shark size to a maximum of 0.7 [mu]g/g for 
a 241 cm fork length (~ 425 lb) individual, still far lower than for 
other sharks examined in the study, including the shortfin mako and the 
sevengill shark (Suk et al., 2009). Although data are unavailable to 
assess the impact of these mercury levels on the health of the common 
thresher shark, low mercury levels exhibited by the common thresher 
shark likely relate to its tendency to feed on small schooling fish and 
cephalopods, at lower trophic levels than the prey consumed by other 
sharks studied.
    In summary, the petition, references cited, and information in our 
files do not comprise substantial information indicating there is 
present or threatened destruction, modification, or curtailment of the 
common thresher shark's habitat or range such that listing may be 
warranted.

Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    The petition states that ``historical and continued trends of 
fishing of this commercially and recreationally valuable shark remain a 
threat,'' listing commercial exploitation as the first threat of 
overutilization of the species. Historically, common thresher sharks 
were primarily caught in the drift gillnet fishery established off the 
West Coast of the United States, which targeted the species in the late 
1970s. The fishery had shifted its focus to a swordfish fishery by the 
mid-1980s due to economic drivers, but also to protect pupping female 
thresher sharks (PFMC, 2003). Since that time, common thresher sharks 
have only been targeted secondarily or caught incidentally in the drift 
gillnet fishery there. West Coast commercial landings are down from 
1,800 metric tons (mt) in the early 1980s to below 200 mt in 2008 and 
2009 (PFMC, 2010). As stated above, based on preliminary stock 
assessment results, there appears to be an initial period of decline 
from 1981 to 1986, followed by a gradual rebuilding of the stock (NMFS 
SWFSC, unpublished data). Average annual landings since 2004 have been 
about 200 mt (PFMC, 2011), well below an established sustainable and 
precautionary harvest level of 450 mt, and this level of landings has 
allowed the population to further rebuild. Regulations on commercial 
fishing operations (e.g., time and area closures) to protect gravid 
females during the pupping season (March through August), combined with 
a switch in the primary target of the driftnet fishery from thresher 
sharks to swordfish, have likely contributed to the rebuilding of the 
common thresher shark in the Eastern Pacific Ocean over the past 25 
years (PMFC, 2003).
    The petition states that in addition to broad commercial harvest of 
the species, direct catch related to the shark fin trade has resulted 
in population decline. No information connecting population declines as 
a result of this direct catch is provided in the petition. The petition 
states that common thresher shark fins are valuable due to their large 
size and longer fin needles. Evidence suggests that the three thresher 
shark species, collectively, may account for approximately 2.3 percent 
of the fins auctioned in Hong Kong, the world's largest fin-trading 
center (Clarke, 2006). This translates to 0.4 million to 3.9 million 
threshers that may enter the global fin trade each year (Clarke, 2006). 
However, information on the species-specific impact of this harvest on 
common thresher shark abundance is not provided by the petitioner, and 
is not available in our files. The bigeye thresher shark is of higher 
value and vulnerability to fishing than the common thresher shark 
(Cortez, 2010); however, the relative proportion of each thresher shark 
species comprising the shark-fin trade is not available in this genus-
level assessment. Overall, evidence that common thresher sharks (and 
threshers in general) are highly valued for their fins and comprise a 
portion of the Hong Kong fin-trading auction suggests that this threat 
may impact the species.
    Indirect catch is another category of overutilization identified by 
the petition, which states that post-release mortality may be high in 
the species. However, no information is provided in the petition to 
connect the effect of bycatch on population declines of the species. In 
our own files, we found evidence to support that adults and juveniles 
of common thresher shark are caught as bycatch in longline, purse seine 
and mid-water fisheries (IATTC, 2006). As stated in the petition, in 
the Northeast Atlantic Ocean prior to 2000, estimated landings 
fluctuated at 13-17 t, and in 2000-2001 they exceeded 100 t, after 
which they dropped to 4 t in 2002 and have not exceeded 7 t since 
(ICES, 2006). In the Mediterranean, there are no large-scale fisheries 
targeting pelagic sharks and rays, but these species are taken as 
bycatch in surface longline fisheries (Cahmi, 2009). In our files, we 
found evidence that, in the last two decades, common thresher sharks 
have declined between 96 and 99 percent in abundance and biomass in the 
Mediterranean Sea (Ferretti, 2008). Currently, there is no commercial 
fishery for common thresher sharks on the East Coast of the United 
States, but they are taken as bycatch on pelagic longlines and in 
gillnets; here, commercial bycatch landings averaged 19,958 kg (dressed 
weight) from 2003 to 2011, with landings peaking at 27,801 kg (dressed 
weight) in 2010 (NMFS, 2012; Gervalis et al., 2013). These landings may 
be linked to declines in the species across the Northwest Atlantic 
portion of its range; however, as discussed earlier, conflicting 
logbook and observer data decrease the certainty of these trends 
(Cort[eacute]s, 2007; Baum, 2010). In the Southwest Atlantic Ocean, off 
the coast of Brazil, big eye thresher

[[Page 11384]]

sharks represent almost 100 percent of thresher sharks caught, and only 
occasionally are common thresher sharks caught in the longline fishery 
(Amorin, 1998).
    The petition identified recreational fishing as the fourth category 
of overutilization. In our files, we found evidence that common 
thresher sharks are valued by recreational sport fishermen throughout 
the species' U.S. East Coast and West Coast range, and those that are 
caught are generally landed; the common thresher shark is considered 
one of the better species for human consumption (Compagno, 2001). The 
species appears to be increasing in importance at shark tournaments in 
the Northeastern United States. As described in the petition, at one 
major tournament, common thresher shark numbers increased steadily such 
that the percent of total catch increased from 0.1 percent to 4.8 from 
1965 to 1995 and jumped to 27.8 percent of the total catch in 2004 
(Gervalis et al., 2013). Heberer (2010) identified the potential 
negative impact of recreational fishing on the survival of the common 
thresher shark by assessing post-release survivorship of sharks 
captured using the caudal-fin-based techniques used by most 
recreational fishermen. Since common thresher sharks use their elongate 
upper caudal lobe to immobilize prey before it is consumed, the 
majority of thresher sharks captured in the recreational fishery are 
hooked in the caudal fin and hauled-in backwards (Heberer, 2010). The 
common thresher is an obligate ram ventilator that requires forward 
motion to ventilate the gills (Heberer, 2010). The reduced ability to 
extract oxygen from the water during capture as well as the stress 
induced from these capture methods may influence recovery following 
release. The findings of Heberer (2010) demonstrate that large tail-
hooked common thresher sharks with prolonged fight times (>=85 min) 
exhibit a heightened stress response, which may contribute to an 
increased mortality rate. This work suggests, especially for larger 
thresher sharks, that recreational catch-and-release may not be an 
effective conservation-based strategy for the species. A recent paper 
by Sepulveda (2014) found similar evidence for high post-release 
mortality of recreationally caught common thresher sharks in the 
California recreational shark fishery. Their results demonstrated that 
caudal-fin-based angling techniques, which often result in trailing 
gear left embedded in the shark, can negatively affect post-release 
survivorship. This work suggests that mouth-based angling techniques 
can, when performed properly, result in a higher survivorship of 
released sharks. However, these techniques are not a common practice. 
Recreational catch varies widely from year to year but has averaged 
roughly 20 mt annually in recent years (CDFG, 2008). The estimated 
level of catch in this fishery may be imprecise because the fishery is 
patchy and sporadic. Although recreational catch rate data are 
unavailable or highly unreliable, evidence for high post-release 
mortality suggests that increases in recreational fishing may pose a 
threat to the common thresher shark.
    Overall, trends throughout the Eastern Pacific Ocean suggest that 
the species either may be rebuilding from historical overexploitation, 
or may be stable. Elsewhere across the species' range, information in 
the petition and in our files suggests that the species may continue to 
experience declines as a result of overutilization. While measures may 
be implemented to improve post-release mortality of a recreational 
common thresher shark fishery, and to reduce bycatch, we found no 
evidence that these measures have been incorporated into common 
practice. In summary, the petition, references cited, and information 
in our files comprise substantial information indicating that listing 
may be warranted because of overutilization for commercial, 
recreational, scientific or educational purposes.

Disease and Predation

    The petitioner does not identify predation and disease as a threat 
to the common thresher shark, and we were unable to find any 
information in our files to suggest that this factor is affecting the 
continued survival of the species.

Inadequacy of Existing Regulatory Mechanisms

    The petition states that ``the U.S. does not provide adequate 
protection for this species. Additionally, this global species lacks 
international protection under the Convention on International Trade in 
Endangered Species (CITES), and regional management mechanisms remain 
ineffective.''
    On the contrary, we found that national fishing regulations on 
common thresher shark fishing in the United States are precautionary, 
and have led to the rebuilding of the species in U.S. waters over the 
last two decades. The Fishery Management Plan for U.S. West Coast 
Fisheries for Highly Migratory Species includes an annual harvest 
guideline of 340 mt for thresher shark. This is a precautionary harvest 
guideline for commercial catch, which is estimated to be 75 percent of 
the regional maximum sustainable yield for this population. Time and 
area restrictions in the pelagic drift gillnet fishery were imposed off 
California in the mid-1980s to protect thresher sharks, and more 
regulations were added in 2000 to protect sea turtles, resulting in 
reduced effort. In the United States Atlantic Ocean, the species has 
been managed as part of the pelagic shark complex under the 2006 
Consolidated Atlantic Highly Migratory Species Fishery Management Plan. 
Management measures include the following: Commercial quotas, limited 
entry, time-area closures, and recreational bag limits. Sharks are 
required to be landed with fins naturally attached to the carcass. 
Overfishing and overfished status is currently unknown (NMFS HMS 3rd 
Qtr 2011 stock status), but preliminary stock assessment data suggest 
that the species is rebuilding in U.S. waters due to management 
measures to conserve the species (SWFSC, unpublished).
    Since we received the petition, the common thresher shark has been 
listed in Appendix II under the International Convention on the 
Conservation of Migratory Species of Wild Animals (CMS). The petitioner 
stated that there are no laws specifically addressing the needs of the 
common thresher shark; however, a CMS Appendix II listing now 
encourages international cooperation towards conservation of the 
species.
    We agree with the petition that the majority of other international 
regulations provide general protection for all sharks, and that 
includes the common thresher shark. The petition asserts that finning 
regulations are ``inadequate'' for protecting the common thresher shark 
species because common thresher sharks may still be caught, either 
directly or indirectly as bycatch. The petition also cites several 
regional fisheries management organizations (RFMOs) that implement a 5-
percent fin-to-carcass ratio regulation, describes what the petitioner 
contends are potential loopholes in those regulations, and states that 
these general regulations are inadequate for the common thresher shark, 
whose larger fins make it a more targeted species. We agree with the 
petitioner that the common thresher shark is highly valued for its 
fins, and can be identified in the shark fin market, although only to 
the genus level. However, we do not find that national and 
international regulations are inadequate for protecting the common 
thresher shark.

[[Page 11385]]

    Finning regulations are a common form of shark management 
regulation and have been adopted by far more countries and regional 
fishery management organizations than the petition lists (see HSI, 
2012). While the petitioner asserts that there may be some loopholes in 
regulations using a 5% fin-to-carcass ratio, we find that the common 
thresher shark is rebuilding in broad portions of its range and is of 
lower vulnerability due to its demographic characteristics, such that 
current regulations are not considered inadequate. In addition, a 
number of countries have also enacted complete shark fishing bans, with 
the Bahamas, Marshall Islands, Honduras, Sabah (Malaysia), and Tokelau 
(an island territory of New Zealand) added to the list in 2011, and an 
area of 1.9 million km off the Cook Islands added in 2012. The petition 
states that Tokelau and the Cook Islands have only partial fishing 
bans, but this statement appears to be based on incomplete information. 
Shark sanctuaries can also be found in the Eastern Tropical Pacific 
Seascape (which encompasses around 2,000,000 km\2\ and includes the 
Galapagos, Cocos, and Malpelo Islands), and in waters off the Maldives, 
Mauritania, Palau, and French Polynesia. Countries, states, and 
territories that prohibit the sale or trade of shark fins or products 
include the Bahamas, Commonwealth of the Northern Mariana Islands, 
American Samoa, Cook Islands, Egypt, French Polynesia, Guam, Republic 
of Marshall Islands, and Sabah. Several U.S. States prohibit the sale 
or trade of shark fins/products as well, including Hawaii, Oregon, 
Washington, California, Illinois, Maryland, Delaware, New York and 
Massachusetts. The U.S. Shark Conservation Act of 2010 protects all 
shark species, making it illegal to remove any of the fins of a shark 
(including the tail) at sea; to have custody, control, or possession of 
any such fin aboard a fishing vessel unless it is naturally attached to 
the corresponding carcass; to transfer any such fin from one vessel to 
another vessel at sea, or to receive any such fin in such transfer, 
without the fin naturally attached to the corresponding carcass; or to 
land any such fin that is not naturally attached to the corresponding 
carcass, or to land any shark carcass without such fins naturally 
attached. Additionally, many cities in Canada also prohibit the sale or 
trade of shark fins/products. All of these measures provide protections 
for the global common thresher shark population.
    The petition also mentions the lack of CITES protections for the 
common thresher shark. The common thresher shark is not a CITES listed 
species, however, a CITES listing would only address threats associated 
with the international trade of the species, and would not address such 
impacts as bycatch or recreational catch-and-release of the species. 
Although a CITES Appendix II listing or international reporting 
requirements would provide better data on the global catch and trade of 
the common thresher shark, the lack of a CITES listing or requirements 
would not suggest that current regulatory mechanisms are inadequate to 
protect the common thresher shark population from becoming endangered 
under the ESA.
    In summary, the petition, references cited, and information in our 
files do not comprise substantial information indicating that the 
species is impacted by inadequacy of regulatory mechanisms such that 
listing may be warranted.

Other Natural or Manmade Factors Affecting Its Existence

    The petition states that the biological constraints of the common 
thresher shark, such as its low reproduction rate (typically 2-4 pups a 
year), coupled with the time required to reach maturity (approximately 
5 years), contribute to the species' vulnerability to harvesting and 
its inability to recover rapidly. It is true that the common thresher 
shark and pelagic sharks, in general, exhibit relatively slow growth 
rates and low fecundity; however, not all species are equally 
vulnerable to fishing pressure due to these life history 
characteristics.
    An ecological risk assessment conducted to inform the International 
Commission for the Conservation of Atlantic Tunas (ICCAT) categorized 
the relative risk of overexploitation of the 11 major species of 
pelagic sharks, including the common thresher shark (Cort[eacute]s et 
al., 2010, 2012). The study derived an overall vulnerability ranking 
for each of the 11 species, which was defined as ``a measure of the 
extent to which the impact of a fishery [Atlantic long line] on a 
species will exceed its biological ability to renew itself'' 
(Cort[eacute]s et al., 2010, 2012). This robust assessment found that 
common thresher sharks, along with pelagic stingrays, are relatively 
productive species that show very low susceptibility to the combined 
pelagic longline fisheries in the Atlantic Ocean (Cort[eacute]s et al., 
2010, 2012). In fact, of 11 species examined, common thresher sharks 
exhibited one of the lowest vulnerability rankings. The relatively low 
vulnerability of the common thresher shark is further supported by a 
recent comparison of demographic models which ranked 26 pelagic sharks 
according to their potential growth rate and rebound potential (Chapple 
et al., 2013). The common thresher shark was found to rank 9 out of 26 
overall in terms of its egg production, rebound potential, potential 
for population increase, and for its stochastic growth rate; again 
ranking among the highest in productivity when compared with other 
pelagic sharks (Chapple et al., 2013). Even within the genus Alopiidae, 
the common thresher shark is considered the fastest-growing and 
earliest-maturing of the three species, and attains the largest size 
(Smith et al., 2008).
    In summary, the petition, references cited, and information in our 
files do not comprise substantial information indicating that the 
species is impacted by ``other natural or manmade factors,'' including 
the life history trait of slow productivity, such that listing of the 
species may be warranted.

Summary of Section 4(a)(1) Factors

    We conclude that the petition does not present substantial 
scientific or commercial information indicating that the ESA section 
(4)(a)(1) threats of ``other manmade or natural factors'' or 
``inadequacy of regulatory mechanisms'' may be causing or contributing 
to an increased risk of extinction for the global population of the 
common thresher shark. In addition, neither the petition nor 
information in our files indicated that the ``present or threatened 
destruction, modification, or curtailment of its habitat or range,'' or 
``disease or predation'' are threats to the species. However, we do 
conclude that the petition and information in our files present 
substantial scientific or commercial information indicating that the 
section 4(a)(1) factor ``overutilization for commercial, recreational, 
scientific, or educational purposes'' may be causing or contributing to 
an increased risk of extinction for the species.

Petition Finding

    Based on the above information and the criteria specified in 50 CFR 
424.14(b)(2), we find that the petition and information readily 
available in our files presents substantial scientific and commercial 
information indicating that the petitioned action of listing the common 
thresher shark worldwide as threatened or endangered may be warranted. 
Therefore, in accordance with section 4(b)(3)(B) of the ESA and NMFS' 
implementing regulations (50

[[Page 11386]]

CFR 424.14(b)(2)), we will commence a status review of the species. 
During the status review, we will determine whether the species 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, we consider the 
common thresher shark to be a candidate species (69 FR 19975; April 15, 
2004). Within 12 months of the receipt of the petition (August 26, 
2015), 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 found to be 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 common thresher shark is endangered or threatened. 
Specifically, we are soliciting information in the following areas: (1) 
Historical and current distribution and abundance of this species 
throughout its range; (2) historical and current population trends; (3) 
life history in marine environments, including identified nursery 
grounds; (4) historical and current data on common thresher shark 
bycatch and retention in industrial, commercial, artisanal, and 
recreational fisheries worldwide; (5) historical and current data on 
common thresher shark discards in global fisheries; (6) data on the 
trade of common thresher shark products, including fins, jaws, meat, 
and teeth; (7) any current or planned activities that may adversely 
impact the species; (8) ongoing or planned efforts to protect and 
restore the species and its habitats; (9) population structure 
information, such as genetics data; and (10) management, regulatory, 
and enforcement information. We request that all information be 
accompanied by: (1) Supporting documentation such as maps, 
bibliographic references, or reprints of pertinent publications; and 
(2) the submitter's name, address, and any association, institution, or 
business that the person represents.

References Cited

    A complete list of references is available upon request to the 
Office of Protected Resources (see ADDRESSES).

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

    Dated: February 25, 2015.
Samuel D. Rauch III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.
[FR Doc. 2015-04409 Filed 3-2-15; 8:45 am]
BILLING CODE 3510-22-P