NACO

National Association of Charterboat Operators

Great Hammerhead Shark Petitioned for Listing as Threatened or Endangered

We, NMFS, announce a 90-day finding on two petitions to list the great hammerhead shark range-wide or, in the alternative, the Northwest Atlantic distinct population segment (DPS) or any other identified DPSs as threatened or endangered under the endangered Species Act (ESA), and to designate critical habitat. 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 June 25, 2013.

 

ADDRESSES: You may submit comments, information, or data on this 

 

document, identified by the code NOAA-NMFS-2013-0046, by any of the 

following methods:

     Electronic Submissions: Submit all electronic comments via 

the Federal eRulemaking Portal. Go to www.regulations.gov/#!docketDetail;D=NOAA-NMFS-2013-0046, click the ``Comment Now!'' icon, 

complete the required fields, and enter or attach your comments.

     Mail: Submit written comments to Office of Protected 

Resources, NMFS, 1315 East-West Highway, Silver Spring, MD 20910.

     Fax: 301-713-4060, Attn: Maggie Miller.

Instructions: 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 by NMFS. All comments received are a part of the 

public record and will generally be posted for public viewing on 

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. NMFS 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: Maggie Miller, NMFS, Office of 

Protected Resources, (301) 427-8403.

 SUPPLEMENTARY INFORMATION: 

 Background

     On December 21, 2012, we received a petition from WildEarth 

Guardians (WEG) to list the great hammerhead shark (Sphyrna mokarran) 

as threatened or endangered under the ESA throughout its entire range, 

or, as an alternative, to list any identified DPSs as threatened or 

endangered. The petitioners also requested that critical habitat be 

designated for the great hammerhead under the ESA. On March 19, 2013, 

we received a petition from Natural Resources Defense Council (NRDC) to 

list the northwest Atlantic DPS of great hammerhead shark as 

threatened, or, as an alternative, to list the great hammerhead shark 

range-wide as threatened, and to designate critical habitat. The joint 

U.S. Fish and Wildlife Service (USFWS)/NMFS Endangered Species Act 

Petition Management Guidance (1996) states that if we receive two 

petitions for the same species, the requests only differ in the 

requested status of the species, and a 90-day finding has not yet been 

made on the earlier petition, then the later petition will be combined 

with the earlier petition and a combined 90-day finding will be 

prepared. Since the initial petition requested listing of the species 

as threatened or endangered and the second petition only requested a 

threatened listing, and a finding has not been made on the initial 

petition, we have combined the WEG and NRDC petitions and this 90-day 

finding will address both. 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 that 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 review with a 

finding as to whether, in fact, 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 more thorough review of the available 

information, as compared to the narrow scope of review at the 90-day 

stage, a finding that the ``petition presents substantial scientific or 

commercial information that the action may be warranted'' at this point 

does not predetermine 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-USFWS (jointly, ``the Services'') policy (DPS 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 

(ESA sections 3(6) and 3(20), respectively, 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 five section 4(a)(1) factors: (1) The 

present or threatened destruction, modification, or curtailment of 

habitat or range; (2) overutilization for commercial, recreational, 

scientific, or educational purposes; (3) disease or predation; (4) 

inadequacy of existing regulatory mechanisms; and (5) 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 the Services (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. 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 petition presents substantial 

information indicating the 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 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 it supports the 

petitioners' assertions. In other words, conclusive information 

indicating that 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 that 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 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.

Distribution and Life History of the Great Hammerhead Shark

    The great hammerhead shark is a circumtropical species that lives 

in coastal-pelagic and semi-oceanic waters from latitudes of 40[deg] N 

to 35[deg] S (Compagno, 1984; Denham et al., 2007). It occurs over 

continental shelves as well as adjacent deep waters, and may also be 

found in coral reefs and lagoons (Compagno, 1984; Denham et al., 2007; 

Bester, n.d.). Great hammerhead sharks are highly mobile and seasonally 

migratory (Compagno, 1984; Denham et al., 2007; Hammerschlag et al., 

2011; Bester, n.d.). In the western Atlantic Ocean, the great 

hammerhead range extends from Massachusetts (although the species is 

rare north of North Carolina), in the United States, to Uruguay, 

including the Gulf of Mexico and Caribbean Sea. In the eastern 

Atlantic, it can be found from Morocco to Senegal, including in the 

Mediterranean Sea. The great hammerhead shark can also be found 

throughout the Indian Ocean and the Red Sea and in the Indo-Pacific 

region from Ryukyu Island south to New Caledonia and east to French 

Polynesia (Bester, n.d.). Distribution in the eastern Pacific Ocean 

extends from southern Baja California, including the Gulf of 

California, to Peru (Compagno, 1984).

    The general life history pattern of the great hammerhead shark is 

that of a long lived (oldest observed maximum age = 44 years; Piercy et 

al., 2010), large, and relatively slow growing species. The great 

hammerhead shark has a laterally expanded head that resembles a hammer, 

hence the common name ``hammerhead,'' and belongs to the Sphyrnidae 

family. The great hammerhead shark is the largest of the hammerheads, 

characterized by a nearly straight anterior margin of the head and 

median indentation in the center in adults, strongly serrated teeth, 

strongly falcate first dorsal and pelvic fins, and a high second dorsal 

fin with a concave rear margin (Compagno, 1984; Bester, n.d.). The body 

of the great hammerhead is fusiform, with the dorsal side colored dark 

brown to light grey or olive that shades to white on the ventral side 

(Compagno, 1984; Bester, n.d.). Fins of adult great hammerheads are 

uniform in color, while the tip of the second dorsal fin of juveniles 

may appear dusky (Bester, n.d.).

    The oldest aged great hammerhead sharks had lengths of 398 cm total 

length (TL) (female--44 years) and 379 cm TL (male--42 years) (Piercy 

et al., 2010), but they can reach lengths of over 610 cm TL (Compagno, 

1984). However, individuals greater than 400 cm TL are rare (Compagno, 

1984; Stevens and Lyle 1989), which Piercy et al. (2010) suggest may be 

attributed to growth overfishing. Estimates for size at maturity range 

from 234 to 269 cm TL for males and 210 to 300 cm TL for females 

(Compagno, 1984; Stevens and Lyle 1989). Male great hammerhead sharks 

have also been shown to grow faster than females (with a growth 

coefficient, k, of 0.16/year for males and 0.11/year for females) but 

reach a smaller asymptotic size (335 cm TL for males versus 389 cm TL 

for females) (Piercy et al., 2010).

    The great hammerhead shark is viviparous (i.e., give birth to live 

young), with a gestation period of 10-11 months, and likely breeds 

every other year (Stevens and Lyle, 1989). Litter sizes range from 6 to 

42 live pups (Compagno, 1984; Stevens and Lyle, 1989). Length at birth 

estimates for great hammerheads range from 50-70 cm TL (Compagno, 1984; 

Stevens and Lyle, 1989).

    The great hammerhead shark is a high trophic level predator 

(Cort[eacute]s, 1999) and opportunistic feeder, with a diet that 

includes a wide variety of teleosts, cephalopods, and crustaceans, with 

a preference for stingrays (Compagno, 1984; Denham et al., 2007).

 

Analysis of Petition and Information Readily Available in NMFS Files

 

    We evaluated the information provided in the petition and readily 

available in our files to determine if the petitions presented 

substantial scientific or commercial information indicating that the 

petitioned actions may be warranted. The petitions contain information 

on the species, including the taxonomy, species description, geographic 

distribution, and habitat, with some information on population status 

and trends in certain locations, and factors contributing to the 

species' decline. The petitions state that commercial fishing, both 

targeted and bycatch, is the primary threat to the great hammerhead 

shark. The petitioners also assert that current habitat destruction, 

deposition of pollutants, lack of adequate regulatory mechanisms 

nationally and worldwide, global climate warming, as well the species' 

biological constraints, increase the susceptibility of the great 

hammerhead shark to extinction.

    According to the WEG petition, all five causal factors in section 

4(a)(1) of the ESA are adversely affecting the continued existence of 

the great hammerhead shark: (A) The present or threatened destruction, 

modification, or curtailment of its habitat or range; (B) 

overutilization for commercial, recreational, scientific, or 

educational purposes; (C) disease or predation; (D) inadequacy of 

existing regulatory mechanisms; and (E) other natural or manmade 

factors affecting its continued existence. The focus of the NRDC 

petition is mainly on the northwest Atlantic population and it 

identified the threats of: (B) overutilization for commercial, 

recreational, scientific, or educational purposes; (D) inadequacy of 

existing regulatory mechanisms; and (E) other natural or manmade 

factors affecting its continued existence. In the following sections, 

we use the information presented in the petition and in our files to 

determine whether the petitioned action may be warranted. If requested 

to list a global population and, alternatively, a DPS, we first 

determine if the petition presents substantial information that the 

petitioned action is warranted for the global population. If it does, 

then we make a positive finding on the petition and will revisit the 

question of DPSs during a status review, if necessary. If the petition 

does not present substantial information that the global population may 

warrant listing, and it has requested that we list any populations of 

the species as threatened or endangered, then we consider whether the 

petition provides substantial information that the requested 

population(s) may qualify as DPSs under the discreteness and 

significance criteria of our joint DPS Policy, and if listing any of 

those DPSs may be warranted. We summarize our analysis and conclusions 

regarding the information presented by the petitioners and in our files 

on the specific ESA section 4(a)(1) factors that we find may be 

affecting the species' risk of global extinction below.

 

Overutilization for Commercial, Recreational, Scientific, or 

Educational Purposes

 

    Information from the petitions and in our files suggests that the 

primary threat to the great hammerhead shark is from fisheries. Great 

hammerhead sharks are both targeted and taken as bycatch in many global 

fisheries (e.g., bottom and pelagic longlines, coastal gillnet 

fisheries, artisanal fisheries). Because of their large fins with high 

fin needle

 

[[Page 24704]]

 

content (a gelatinous product used to make shark fin soup), hammerheads 

fetch a high commercial value in the Asian shark fin trade (Abercrombie 

et al., 2005). However, the WEG petition overstates the contribution of 

great hammerheads in the Hong Kong fin trade market by presenting 

information on the trade of scalloped, smooth, and great hammerhead 

fins together. According to a genetic study that examined the 

concordance between assigned Hong Kong market categories and the 

corresponding fins, the great hammerhead market category ``Gu pian'' 

had an 88 percent concordance rate, indicating that traders are able to 

accurately identify and separate great hammerhead fins from the other 

hammerhead species (Abercrombie et al., 2005; Clarke et al., 2006a). As 

such, here we provide the information on a finer scale level (down to 

the species level) to evaluate the extent that the fin trade may 

contribute to the overutilization of the great hammerhead shark. 

According to Clarke et al. (2006a), S. mokarran is estimated to 

comprise approximately 1.5 percent of the total fins traded annually in 

the Hong Kong fin market. As mentioned above, great hammerhead fins are 

primarily traded under the ``Gu pian'' market category, where the 

market value for the average, wholesale, unprocessed fin is around 

$135/kg, the most for any of the hammerhead fins (Abercrombie et al., 

2005). Extrapolating the fin data to numbers of sharks, Clarke et al. 

(2006b) estimates that around 375,000 (95 percent confidence interval = 

130,000-1.1 million) individuals of this species (equivalent to a 

biomass of around 21,000 metric tons, (mt)) are traded annually in the 

Hong Kong fin market. Given their high price in the Hong Kong market, 

there is concern that many great hammerheads caught as incidental catch 

may be kept for the fin trade as opposed to released alive.

    In the United States, great hammerhead sharks are mainly caught as 

bycatch in commercial longline and net fisheries and by recreational 

fishers using rod and reel. A recent stock assessment by Jiao et al. 

(2011) used a Bayesian hierarchical approach to assess the data-poor 

hammerhead species and found that the northwestern Atlantic and Gulf of 

Mexico great hammerhead population likely became overfished in the mid-

1980s and experienced overfishing periodically from 1983 to 1997. 

However, after 2001, the models showed that the risk of overfishing was 

very low and that this population is probably still overfished but no 

longer experiencing overfishing (Jiao et al., 2011), likely a result of 

the implementation of stronger fishery management regulations since the 

early 1990s. Under the Magnuson-Stevens Fishery Conservation and 

Management Act (MSA), the term ``overfishing'' is defined as occurring 

when a stock experiences ``a level of fishing mortality that 

jeopardizes the capacity of a stock or stock complex to produce MSY 

[maximum sustainable yield] on a continuing basis'' (50 CFR 600.310). 

An ``overfished'' stock is defined as a stock whose biomass has 

declined below a level that jeopardizes the capacity of the stock to 

produce MSY on a continuing basis (50 CFR 600.310). However, it is 

important to note that these MSA classifications are based on different 

criteria (i.e., achieving MSY) than threatened or endangered statuses 

under the ESA. As such, ``overfished'' and ``overfishing'' 

classifications do not necessarily indicate that a species may warrant 

listing because they do not evaluate a species' extinction risk. 

However, they are relevant considerations for us to consider when we 

evaluate potential threats to the species from overutilization for 

commercial or recreational purposes.

    In Central America and the Caribbean, there are very little data on 

great hammerhead catches. The WEG petition references Denham et al. 

(2007) which states that hammerheads were heavily fished by longlines 

off the coast of Belize in the 1980s and early 1990s, leading to an 

observed decline in the abundance and size of hammerheads and prompting 

a halt in the Belize-based shark fishery. Fishing pressure on 

hammerheads still continues as a result of Guatemalan fishermen 

entering Belizean waters (Denham et al., 2007). However, catch records 

from the Cuban directed shark fishery show a small increase in the mean 

size of great hammerheads since 1992, suggesting partial recovery of 

the species in this region (Denham et al. 2007).

    The WEG petition also references a study (Feretti et al., 2008) 

that indicated that the population of smooth, scalloped, and great 

hammerheads in the Mediterranean Sea has experienced a greater than 99 

percent decline in abundance and biomass; however, the authors of this 

study note that only Sphyrna zygaena (smooth hammerhead) was assessed 

because the other hammerhead species occurred only sporadically in 

historical records. As such, this is not an appropriate index of the 

abundance of the other hammerhead species in the Mediterranean Sea and 

does not indicate overutilization of the great hammerhead shark in this 

region.

    In the Eastern Atlantic, off West Africa, the WEG petition states 

that the ``great hammerhead population is believed to have fallen 80 

percent as a result of unmanaged and unmonitored fisheries,'' but we 

could not verify the original source of this statistic. Data from the 

European pelagic freezer-trawler fishery that operates off Mauritania 

shows hammerhead species, including S. mokarran, constitute a 

significant component of the fishery's bycatch. Between 2001 and 2005, 

42 percent of the retained pelagic megafauna bycatch from over 1,400 

freezer-trawl sets consisted of hammerhead species, with around 75 

percent of the hammerhead catch juveniles of 0.50-1.40 m in length 

(Zeeberg et al., 2006). According to Denham et al. (2007), the sub-

regional plan of action for sharks of West Africa identified S. 

mokarran as particularly threatened in the region, with a noticeable 

decline in the population and collapse of landings. Citing unpublished 

data and anecdotal evidence, Denham et al. (2007) suggests that S. 

mokarran is ``almost extirpated'' from waters off Mauritania to Angola 

after previously being abundant in these areas in the early 1980s. The 

growth of fisheries targeting sharks in this region for the lucrative 

fin trade has likely contributed to the great hammerhead decline. By 

the 1980s, many fishers were specializing in catching sharks (Denham et 

al., 2007), with some artisanal fisheries in West Africa specifically 

specializing in catching sphyrnid species (CITES, 2010).

    In the Indian Ocean, pelagic sharks, including the great 

hammerhead, are targeted in various fisheries, including semi-

industrial, artisanal, and recreational fisheries. Countries that fish 

for sharks include: Egypt, India, Iran, Oman, Saudi Arabia, Sudan, 

United Arab Emirates, and Yemen, where the probable or actual status of 

shark populations is unknown, and Maldives, Kenya, Mauritius, 

Seychelles, South Africa, and United Republic of Tanzania, where the 

actual status of shark population is presumed to be fully to 

overexploited (de Young, 2006). Analysis of fishery-independent data 

from the KwaZulu-Natal beach protection program off South Africa 

revealed declines in the catch rates of S. mokarran since the late 

1970s. Specifically, from 1978-2003, annual catch per unit effort 

(CPUE; in number of sharks per km net year) of S. mokarran declined by 

79 percent, from 0.44 to 0.09 (Dudley and Simpfendorfer, 2006). The 

results were statistically significant, with the slope of the linear

 

[[Page 24705]]

 

regression = -0.014, and the majority of the catch (greater than 64 

percent) being immature great hammerhead sharks (Dudley and 

Simpfendorfer, 2006).

    In Australian waters, sharks are caught by commercial, recreational 

and traditional fishers as targeted catch, retained catch, and bycatch. 

Almost all sharks landed in Australia are used for domestic 

consumption. According to Bensley et al. (2010), the annual commercial 

Australian shark catch from 1996 to 2006 ranged from about 8,600 mt to 

11,500 mt; however, the reporting of catch weights varied due to the 

state of processing (e.g., whole weight, processed weight, landed 

weight, etc.). Data from protective shark meshing programs off beaches 

in New South Wales (NSW) and Queensland suggest declines in hammerhead 

populations off the east coast of Australia. Over a 35-year period, the 

number of hammerheads caught per year in NSW beach nets decreased by 

more than 90 percent, from over 300 individuals in 1973 to less than 30 

in 2008, although the majority of the hammerhead catch was likely S. 

zygaena (Williamson, 2011). Similarly, data from the Queensland shark 

control program indicate declines of around 79 percent in hammerhead 

shark abundance between 1986 and 2010 (although it was estimated that 

S. lewini made up the majority of this catch) (Queensland Department of 

Employment, Economic Development and Innovation (QLD DEEDI), 2011). S. 

mokarran abundance in the nets fluctuated over the years, but remained 

below 20 individuals per year, until 2008/2009 when a peak of 33 

individuals was caught in the net (QLD DEEDI, 2011). Abundance has 

since declined by around 48 percent to 17 individuals in 2011/2012 (QLD 

DEEDI, 2011). In Australia's northwest marine region, Heupel and 

McAuley (2007) analyzed CPUE data from the northern shark fisheries for 

the period of 1996-2005 and reported hammerhead abundance declines of 

58-76 percent.

    Given the value and contribution of great hammerhead fins in the 

international fin trade and the evidence of historical and current 

fishing pressure and subsequent population declines, we conclude that 

the information in the petitions and in our files suggests that global 

fisheries are impacting great hammerhead shark populations to a degree 

that raises concerns of a risk of extinction.

 

 Inadequacy of Existing Regulatory Mechanisms

 

    The petitions assert that the existing international and domestic 

management measures of several nations have failed to adequately 

protect the great hammerhead or stop ongoing population declines and 

present information on some of the current national and international 

shark regulations. Although the WEG petition mentions the International 

Convention for the Conservation of Atlantic Tunas (ICCAT) 

Recommendation 10-08, prohibiting the retention, transshipment, 

landing, storing, or offering for sale any part or carcass of 

hammerhead sharks of the family Sphyrnidae (except for bonnethead 

shark), the petition states that ``these are merely recommendations and 

do not do enough to bind the relevant actors.'' On the contrary, the 

``relevant actors,'' of which we assume the petitioner is referring to 

ICCAT Contracting Parties, are bound to implement management measures 

consistent with achieving ICCAT recommendations under Article VIII of 

the ICCAT Convention. On August 29, 2011, we finalized the 

implementation of Recommendation 10-08 through passage of a final rule 

that prohibits the retention, possession, transshipment, landing, 

storing, selling or purchasing of oceanic whitetip sharks or scalloped, 

smooth, or great hammerheads by U.S. commercial highly migratory 

species (HMS) pelagic longline fishery and recreational fisheries for 

tunas, swordfish, and billfish in the Atlantic Ocean, including the 

Caribbean Sea and Gulf of Mexico (76 FR 53652; August 29, 2011). 

However, the exemption available to developing coastal States in this 

ICCAT recommendation, which allows them to retain hammerhead sharks for 

local consumption as long as no hammerhead parts enter international 

trade, is troubling. As this exception provides a lesser degree of 

protection for hammerhead sharks in some developing coastal States, it 

may be a cause for concern for great hammerhead populations in the 

Atlantic Ocean.

    In addition, the petitions note that there is limited international 

management of the great hammerhead shark, which is generally allowed to 

be harvested outside of U.S. waters and ICCAT fisheries. The other 

regional fishery management organizations (RFMOs) do not have any 

species-specific regulations for great hammerhead sharks, but have 

addressed the controversial practice of shark finning (which involves 

harvesting sharks, severing their fins and returning their remaining 

carcasses to the sea) by adopting shark finning bans to reduce the 

number of sharks killed solely for their fins. However, as the WEG 

petition points out, these finning bans are enforced by monitoring the 

fin-to-carcass weight ratio, with this ratio set at 5 percent (i.e., 

onboard fins cannot weigh more than 5 percent of the weight of sharks 

onboard, up to the first point of landing). In a study that looked at 

species-specific shark-fin-to-body-mass ratios, the great hammerhead 

shark had an average wet-fin-to-round-mass ratio of 1.96 percent (Biery 

and Pauly, 2012), much lower than the designated 5 percent. These 

results suggest that fishers of great hammerhead sharks would be able 

to land more fins than bodies and still pass inspection, essentially 

allowing them to continue the wasteful practice of shark finning at sea 

in these RFMO convention areas.

    Domestic laws and regulations for other nations may also be lacking 

in certain areas of the great hammerhead range. For example, in Central 

America and the Caribbean, Kyne et al. (2012) notes that due in large 

part to the number of autonomous countries found in this region, the 

management of shark species remains largely disjointed, with some 

countries lacking basic fisheries regulations, and weak enforcement of 

those they do have. Off West Africa, weak fisheries management has led 

to many of their fish stocks being declared fully exploited to 

overexploited (FAO, 2012). Environmental Justice Foundation (EJF) 

(2012) notes that even countries with stricter fishing regulations in 

this region lack the resources to provide effective or, for that 

matter, any enforcement, with some countries lacking basic monitoring 

systems. In addition, reports of illegal, unregulated, and unreported 

fishing are prevalent in the waters off West Africa and account for 

around 37 percent of the region's catch, the highest regional estimate 

of illegal fishing worldwide (Agnew et al., 2009; EJF, 2012). Illegal 

fishing is also common in the western central Pacific and eastern 

Indian Ocean (Agnew et al., 2009), with many reports of vessels being 

caught with illegal shark carcasses and fins onboard (Paul, 2009). As 

the NRDC petition notes, ``as recently as 2011, illegal fishing and 

finning of hammerhead sharks was documented in the Galapagos Marine 

Reserve,'' suggesting that illegal shark fishing may still be an 

impediment to conservation despite increasing international efforts to 

protect sharks. Without stricter fishery regulations or enforcement, 

there is concern that captures of great hammerhead sharks, both legal 

and illegal, may be kept, especially considering the high price that 

great hammerhead fins fetch in the international fin trade market. The 

information in the petitions and in our

 

[[Page 24706]]

 

files suggests that while there is increasing support for national and 

international shark conservation and regulation, the existing 

regulatory mechanisms in some portions of the S. mokarran range may be 

inadequate to address threats to the global great hammerhead 

population.

 

Other Natural or Manmade Factors

 

    The WEG petition contends that ``biological vulnerability'' in the 

form of long gestation periods, late maturity, and large size makes 

great hammerheads especially susceptible to overutilization. The 

species has low productivity (intrinsic rate of population increase per 

year = 0.070; Cort[eacute]s et al., 2012), which makes it generally 

vulnerable to depletion and slow to recover from overexploitation. In 

addition, both petitions mention the great hammerhead sharks' high 

capture mortality rate on bottom longline (BLL) gear. This high at-

vessel mortality makes the shark vulnerable to fishing pressure, with 

any capture of this species, regardless of whether the fishing is 

targeted or incidental, contributing to its fishing mortality. In the 

northwest Atlantic, at-vessel fishing mortality on BLL gear (averaged 

for all age groups) was estimated to be 93.8 percent for great 

hammerhead sharks (Morgan and Burgess, 2007). However, in an ecological 

risk assessment of 20 shark stocks, Cortes et al. (2012) found that the 

great hammerhead ranked 14th in terms of its susceptibility to pelagic 

longline fisheries in the Atlantic Ocean. This information suggests 

that the species' biological vulnerability (low productivity and high 

at-vessel mortality) may be a threat in certain fisheries, possibly 

contributing to an increased risk of extinction, but may not be a cause 

for concern in other fisheries.

 

Conclusion

 

    We conclude that the information in the petition and in our files 

suggests that fisheries, inadequate existing regulatory mechanisms, and 

other natural factors may be impacting great hammerhead shark 

populations to a degree that raises concerns of a risk of extinction, 

with evidence of population depletions throughout the entire range of 

the great hammerhead shark. We find that the WEG petition's discussion 

of the present and threatened destruction, modification, and 

curtailment of the great hammerhead's habitat and range due to growing 

human populations and both petitions' discussions of climate change 

threats to habitats do not constitute substantial information 

indicating that listing may be warranted. The petitioners fail to show 

if the great hammerhead shark is responding in a negative fashion to 

those specific threats. For example, neither petition provides 

evidence, nor is there information in our files, to indicate that 

hypoxic occurrences and dead zones, a result of growing human 

populations, urban pollution, and climate warming, negatively impact 

shark populations. In fact, shark abundance can be very high in dead 

zones (Driggers and Hoffmayer, personal communication, 2013). In 

addition, both petitions assert that the loss of coral reef habitat due 

to climate change puts great hammerheads at risk of extinction; 

however, great hammerhead sharks are highly migratory species and are 

not limited to reef habitats. Additionally, another interpretation of 

the information could be that as ocean temperatures warm, more adequate 

habitat for great hammerheads would become available as they are a 

tropical species. The WEG petition also does not provide substantial 

information indicating that listing may be warranted due to the 

presence of mercury, PCBs, and arsenic in the great hammerhead shark's 

environment. The WEG petition references studies that examined the 

concentrations of these metals and organic compounds in different shark 

species, but it does not provide information, nor is there information 

in the references or in our files, on the effects of these substances 

and concentrations on great hammerhead sharks. In fact, the petition 

quotes a reference, stating that ``scientists found that `[a]ll life-

history stages [of the great white shark] may be vulnerable to high 

body burdens of anthropogenic toxins; how these may impact the 

population is not known.' '' In addition, one of the petition's 

references, Storelli et al. (2003), states ``[i]t is hypothesed [sic] 

that the large size of elasmobranch liver provides a greater ability to 

eliminate organic toxicants than in other fishes.'' The reference also 

mentions that in marine mammals selenium has a detoxifying effect 

against mercury intoxication when the molar ratio between the two 

metals is close to one, and observed similar ratios in shark liver 

``indicating that this particular mechanism may also be valid for 

sharks'' (Storelli et al., 2003). We conclude that given the 

information in the petition, references, and in our files, the petition 

fails to show that the great hammerhead may be responding in a negative 

fashion to these proposed threats.

 

Summary of ESA Section 4(a)(1) Factors

 

    We conclude that the petitions present substantial scientific or 

commercial information indicating that the petitioned action may be 

warranted due to a combination of the following three ESA section 

4(a)(1) factors that may be causing or contributing to an increased 

risk of extinction for the great hammerhead shark: Overutilization for 

commercial, recreational, scientific, or educational purposes, 

inadequate existing regulatory mechanisms, and other natural factors. 

However, we conclude that the WEG petition does not present substantial 

scientific or commercial information indicating that the petitioned 

action may be warranted based on the remaining two ESA section 4(a)(1) 

factors: The present or threatened destruction, modification, or 

curtailment of its habitat or range; or disease or predation.

 

Petition Finding

 

    After reviewing the information contained in the petitions, as well 

as information readily available in our files, and based on the above 

analysis, we conclude that the petitions present substantial scientific 

information indicating that the petitioned action of listing the great 

hammerhead shark range-wide as threatened or endangered may be 

warranted. Therefore, in accordance with section 4(b)(3)(B) of the ESA 

and NMFS' implementing regulations (50 CFR 424.14(b)(2)), we will 

commence a status review of the species. During our status review, we 

will first determine whether the species is in danger of extinction 

(endangered) or likely to become so (threatened) throughout all or a 

significant portion of its range. If it is not, then we will consider 

whether any populations meet the DPS policy criteria, and if so, 

whether any of these are threatened or endangered throughout all or a 

significant portion of their ranges. We now initiate this review, and 

thus, the great hammerhead shark is considered to be a candidate 

species (69 FR 19975; April 15, 2004). Within 12 months of the receipt 

of the petition (December 21, 2013), we will make a finding as to 

whether listing the species (or any identified DPSs) as endangered or 

threatened is warranted as required by section 4(b)(3)(B) of the ESA. 

If listing the species (or any identified DPSs) 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 on 

whether the great hammerhead shark is endangered or

 

[[Page 24707]]

 

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 great 

hammerhead shark bycatch and retention in industrial, commercial, 

artisanal, and recreational fisheries worldwide; (5) historical and 

current data on great hammerhead shark discards in global fisheries; 

(6) data on the trade of great hammerhead 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 their 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.

 

We, NMFS, announce a 90-day finding on two petitions to list 

the great hammerhead shark (Sphyrna mokarran) range-wide or, in the 

alternative, the Northwest Atlantic distinct population segment (DPS) 

or any other identified DPSs as threatened or endangered under the 

Endangered Species Act (ESA), and to designate critical habitat. 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.

 

DATES: Information and comments on the subject action must be received 

by June 25, 2013.

 

ADDRESSES: You may submit comments, information, or data on this 

document, identified by the code NOAA-NMFS-2013-0046, by any of the 

following methods:

     Electronic Submissions: Submit all electronic comments via 

the Federal eRulemaking Portal. Go to www.regulations.gov/#!docketDetail;D=NOAA-NMFS-2013-0046, click the ``Comment Now!'' icon, 

complete the required fields, and enter or attach your comments.

     Mail: Submit written comments to Office of Protected 

Resources, NMFS, 1315 East-West Highway, Silver Spring, MD 20910.

     Fax: 301-713-4060, Attn: Maggie Miller.

    Instructions: 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 by NMFS. All comments received are a part of the 

public record and will generally be posted for public viewing on 

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. NMFS 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: Maggie Miller, NMFS, Office of 

Protected Resources, (301) 427-8403.

 

SUPPLEMENTARY INFORMATION: 

 

Background

 

    On December 21, 2012, we received a petition from WildEarth 

Guardians (WEG) to list the great hammerhead shark (Sphyrna mokarran) 

as threatened or endangered under the ESA throughout its entire range, 

or, as an alternative, to list any identified DPSs as threatened or 

endangered. The petitioners also requested that critical habitat be 

designated for the great hammerhead under the ESA. On March 19, 2013, 

we received a petition from Natural Resources Defense Council (NRDC) to 

list the northwest Atlantic DPS of great hammerhead shark as 

threatened, or, as an alternative, to list the great hammerhead shark 

range-wide as threatened, and to designate critical habitat. The joint 

U.S. Fish and Wildlife Service (USFWS)/NMFS Endangered Species Act 

Petition Management Guidance (1996) states that if we receive two 

petitions for the same species, the requests only differ in the 

requested status of the species, and a 90-day finding has not yet been 

made on the earlier petition, then the later petition will be combined 

with the earlier petition and a combined 90-day finding will be 

prepared. Since the initial petition requested listing of the species 

as threatened or endangered and the second petition only requested a 

threatened listing, and a finding has not been made on the initial 

petition, we have combined the WEG and NRDC petitions and this 90-day 

finding will address both. 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 that 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

 

[[Page 24702]]

 

conduct a comprehensive review of the best available scientific and 

commercial information. In such cases, we conclude the review with a 

finding as to whether, in fact, 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 more thorough review of the available 

information, as compared to the narrow scope of review at the 90-day 

stage, a finding that the ``petition presents substantial scientific or 

commercial information that the action may be warranted'' at this point 

does not predetermine 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-USFWS (jointly, ``the Services'') policy (DPS 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 

(ESA sections 3(6) and 3(20), respectively, 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 five section 4(a)(1) factors: (1) The 

present or threatened destruction, modification, or curtailment of 

habitat or range; (2) overutilization for commercial, recreational, 

scientific, or educational purposes; (3) disease or predation; (4) 

inadequacy of existing regulatory mechanisms; and (5) 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 the Services (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. 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 petition presents substantial 

information indicating the 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 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 it supports the 

petitioners' assertions. In other words, conclusive information 

indicating that 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 that 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 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

 

[[Page 24703]]

 

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 Hammerhead Shark

 

    The great hammerhead shark is a circumtropical species that lives 

in coastal-pelagic and semi-oceanic waters from latitudes of 40[deg] N 

to 35[deg] S (Compagno, 1984; Denham et al., 2007). It occurs over 

continental shelves as well as adjacent deep waters, and may also be 

found in coral reefs and lagoons (Compagno, 1984; Denham et al., 2007; 

Bester, n.d.). Great hammerhead sharks are highly mobile and seasonally 

migratory (Compagno, 1984; Denham et al., 2007; Hammerschlag et al., 

2011; Bester, n.d.). In the western Atlantic Ocean, the great 

hammerhead range extends from Massachusetts (although the species is 

rare north of North Carolina), in the United States, to Uruguay, 

including the Gulf of Mexico and Caribbean Sea. In the eastern 

Atlantic, it can be found from Morocco to Senegal, including in the 

Mediterranean Sea. The great hammerhead shark can also be found 

throughout the Indian Ocean and the Red Sea and in the Indo-Pacific 

region from Ryukyu Island south to New Caledonia and east to French 

Polynesia (Bester, n.d.). Distribution in the eastern Pacific Ocean 

extends from southern Baja California, including the Gulf of 

California, to Peru (Compagno, 1984).

    The general life history pattern of the great hammerhead shark is 

that of a long lived (oldest observed maximum age = 44 years; Piercy et 

al., 2010), large, and relatively slow growing species. The great 

hammerhead shark has a laterally expanded head that resembles a hammer, 

hence the common name ``hammerhead,'' and belongs to the Sphyrnidae 

family. The great hammerhead shark is the largest of the hammerheads, 

characterized by a nearly straight anterior margin of the head and 

median indentation in the center in adults, strongly serrated teeth, 

strongly falcate first dorsal and pelvic fins, and a high second dorsal 

fin with a concave rear margin (Compagno, 1984; Bester, n.d.). The body 

of the great hammerhead is fusiform, with the dorsal side colored dark 

brown to light grey or olive that shades to white on the ventral side 

(Compagno, 1984; Bester, n.d.). Fins of adult great hammerheads are 

uniform in color, while the tip of the second dorsal fin of juveniles 

may appear dusky (Bester, n.d.).

    The oldest aged great hammerhead sharks had lengths of 398 cm total 

length (TL) (female--44 years) and 379 cm TL (male--42 years) (Piercy 

et al., 2010), but they can reach lengths of over 610 cm TL (Compagno, 

1984). However, individuals greater than 400 cm TL are rare (Compagno, 

1984; Stevens and Lyle 1989), which Piercy et al. (2010) suggest may be 

attributed to growth overfishing. Estimates for size at maturity range 

from 234 to 269 cm TL for males and 210 to 300 cm TL for females 

(Compagno, 1984; Stevens and Lyle 1989). Male great hammerhead sharks 

have also been shown to grow faster than females (with a growth 

coefficient, k, of 0.16/year for males and 0.11/year for females) but 

reach a smaller asymptotic size (335 cm TL for males versus 389 cm TL 

for females) (Piercy et al., 2010).

    The great hammerhead shark is viviparous (i.e., give birth to live 

young), with a gestation period of 10-11 months, and likely breeds 

every other year (Stevens and Lyle, 1989). Litter sizes range from 6 to 

42 live pups (Compagno, 1984; Stevens and Lyle, 1989). Length at birth 

estimates for great hammerheads range from 50-70 cm TL (Compagno, 1984; 

Stevens and Lyle, 1989).

    The great hammerhead shark is a high trophic level predator 

(Cort[eacute]s, 1999) and opportunistic feeder, with a diet that 

includes a wide variety of teleosts, cephalopods, and crustaceans, with 

a preference for stingrays (Compagno, 1984; Denham et al., 2007).

 

Analysis of Petition and Information Readily Available in NMFS Files

 

    We evaluated the information provided in the petition and readily 

available in our files to determine if the petitions presented 

substantial scientific or commercial information indicating that the 

petitioned actions may be warranted. The petitions contain information 

on the species, including the taxonomy, species description, geographic 

distribution, and habitat, with some information on population status 

and trends in certain locations, and factors contributing to the 

species' decline. The petitions state that commercial fishing, both 

targeted and bycatch, is the primary threat to the great hammerhead 

shark. The petitioners also assert that current habitat destruction, 

deposition of pollutants, lack of adequate regulatory mechanisms 

nationally and worldwide, global climate warming, as well the species' 

biological constraints, increase the susceptibility of the great 

hammerhead shark to extinction.

    According to the WEG petition, all five causal factors in section 

4(a)(1) of the ESA are adversely affecting the continued existence of 

the great hammerhead shark: (A) The present or threatened destruction, 

modification, or curtailment of its habitat or range; (B) 

overutilization for commercial, recreational, scientific, or 

educational purposes; (C) disease or predation; (D) inadequacy of 

existing regulatory mechanisms; and (E) other natural or manmade 

factors affecting its continued existence. The focus of the NRDC 

petition is mainly on the northwest Atlantic population and it 

identified the threats of: (B) overutilization for commercial, 

recreational, scientific, or educational purposes; (D) inadequacy of 

existing regulatory mechanisms; and (E) other natural or manmade 

factors affecting its continued existence. In the following sections, 

we use the information presented in the petition and in our files to 

determine whether the petitioned action may be warranted. If requested 

to list a global population and, alternatively, a DPS, we first 

determine if the petition presents substantial information that the 

petitioned action is warranted for the global population. If it does, 

then we make a positive finding on the petition and will revisit the 

question of DPSs during a status review, if necessary. If the petition 

does not present substantial information that the global population may 

warrant listing, and it has requested that we list any populations of 

the species as threatened or endangered, then we consider whether the 

petition provides substantial information that the requested 

population(s) may qualify as DPSs under the discreteness and 

significance criteria of our joint DPS Policy, and if listing any of 

those DPSs may be warranted. We summarize our analysis and conclusions 

regarding the information presented by the petitioners and in our files 

on the specific ESA section 4(a)(1) factors that we find may be 

affecting the species' risk of global extinction below.

 

Overutilization for Commercial, Recreational, Scientific, or 

Educational Purposes

 

    Information from the petitions and in our files suggests that the 

primary threat to the great hammerhead shark is from fisheries. Great 

hammerhead sharks are both targeted and taken as bycatch in many global 

fisheries (e.g., bottom and pelagic longlines, coastal gillnet 

fisheries, artisanal fisheries). Because of their large fins with high 

fin needle

 

[[Page 24704]]

 

content (a gelatinous product used to make shark fin soup), hammerheads 

fetch a high commercial value in the Asian shark fin trade (Abercrombie 

et al., 2005). However, the WEG petition overstates the contribution of 

great hammerheads in the Hong Kong fin trade market by presenting 

information on the trade of scalloped, smooth, and great hammerhead 

fins together. According to a genetic study that examined the 

concordance between assigned Hong Kong market categories and the 

corresponding fins, the great hammerhead market category ``Gu pian'' 

had an 88 percent concordance rate, indicating that traders are able to 

accurately identify and separate great hammerhead fins from the other 

hammerhead species (Abercrombie et al., 2005; Clarke et al., 2006a). As 

such, here we provide the information on a finer scale level (down to 

the species level) to evaluate the extent that the fin trade may 

contribute to the overutilization of the great hammerhead shark. 

According to Clarke et al. (2006a), S. mokarran is estimated to 

comprise approximately 1.5 percent of the total fins traded annually in 

the Hong Kong fin market. As mentioned above, great hammerhead fins are 

primarily traded under the ``Gu pian'' market category, where the 

market value for the average, wholesale, unprocessed fin is around 

$135/kg, the most for any of the hammerhead fins (Abercrombie et al., 

2005). Extrapolating the fin data to numbers of sharks, Clarke et al. 

(2006b) estimates that around 375,000 (95 percent confidence interval = 

130,000-1.1 million) individuals of this species (equivalent to a 

biomass of around 21,000 metric tons, (mt)) are traded annually in the 

Hong Kong fin market. Given their high price in the Hong Kong market, 

there is concern that many great hammerheads caught as incidental catch 

may be kept for the fin trade as opposed to released alive.

    In the United States, great hammerhead sharks are mainly caught as 

bycatch in commercial longline and net fisheries and by recreational 

fishers using rod and reel. A recent stock assessment by Jiao et al. 

(2011) used a Bayesian hierarchical approach to assess the data-poor 

hammerhead species and found that the northwestern Atlantic and Gulf of 

Mexico great hammerhead population likely became overfished in the mid-

1980s and experienced overfishing periodically from 1983 to 1997. 

However, after 2001, the models showed that the risk of overfishing was 

very low and that this population is probably still overfished but no 

longer experiencing overfishing (Jiao et al., 2011), likely a result of 

the implementation of stronger fishery management regulations since the 

early 1990s. Under the Magnuson-Stevens Fishery Conservation and 

Management Act (MSA), the term ``overfishing'' is defined as occurring 

when a stock experiences ``a level of fishing mortality that 

jeopardizes the capacity of a stock or stock complex to produce MSY 

[maximum sustainable yield] on a continuing basis'' (50 CFR 600.310). 

An ``overfished'' stock is defined as a stock whose biomass has 

declined below a level that jeopardizes the capacity of the stock to 

produce MSY on a continuing basis (50 CFR 600.310). However, it is 

important to note that these MSA classifications are based on different 

criteria (i.e., achieving MSY) than threatened or endangered statuses 

under the ESA. As such, ``overfished'' and ``overfishing'' 

classifications do not necessarily indicate that a species may warrant 

listing because they do not evaluate a species' extinction risk. 

However, they are relevant considerations for us to consider when we 

evaluate potential threats to the species from overutilization for 

commercial or recreational purposes.

    In Central America and the Caribbean, there are very little data on 

great hammerhead catches. The WEG petition references Denham et al. 

(2007) which states that hammerheads were heavily fished by longlines 

off the coast of Belize in the 1980s and early 1990s, leading to an 

observed decline in the abundance and size of hammerheads and prompting 

a halt in the Belize-based shark fishery. Fishing pressure on 

hammerheads still continues as a result of Guatemalan fishermen 

entering Belizean waters (Denham et al., 2007). However, catch records 

from the Cuban directed shark fishery show a small increase in the mean 

size of great hammerheads since 1992, suggesting partial recovery of 

the species in this region (Denham et al. 2007).

    The WEG petition also references a study (Feretti et al., 2008) 

that indicated that the population of smooth, scalloped, and great 

hammerheads in the Mediterranean Sea has experienced a greater than 99 

percent decline in abundance and biomass; however, the authors of this 

study note that only Sphyrna zygaena (smooth hammerhead) was assessed 

because the other hammerhead species occurred only sporadically in 

historical records. As such, this is not an appropriate index of the 

abundance of the other hammerhead species in the Mediterranean Sea and 

does not indicate overutilization of the great hammerhead shark in this 

region.

    In the Eastern Atlantic, off West Africa, the WEG petition states 

that the ``great hammerhead population is believed to have fallen 80 

percent as a result of unmanaged and unmonitored fisheries,'' but we 

could not verify the original source of this statistic. Data from the 

European pelagic freezer-trawler fishery that operates off Mauritania 

shows hammerhead species, including S. mokarran, constitute a 

significant component of the fishery's bycatch. Between 2001 and 2005, 

42 percent of the retained pelagic megafauna bycatch from over 1,400 

freezer-trawl sets consisted of hammerhead species, with around 75 

percent of the hammerhead catch juveniles of 0.50-1.40 m in length 

(Zeeberg et al., 2006). According to Denham et al. (2007), the sub-

regional plan of action for sharks of West Africa identified S. 

mokarran as particularly threatened in the region, with a noticeable 

decline in the population and collapse of landings. Citing unpublished 

data and anecdotal evidence, Denham et al. (2007) suggests that S. 

mokarran is ``almost extirpated'' from waters off Mauritania to Angola 

after previously being abundant in these areas in the early 1980s. The 

growth of fisheries targeting sharks in this region for the lucrative 

fin trade has likely contributed to the great hammerhead decline. By 

the 1980s, many fishers were specializing in catching sharks (Denham et 

al., 2007), with some artisanal fisheries in West Africa specifically 

specializing in catching sphyrnid species (CITES, 2010).

    In the Indian Ocean, pelagic sharks, including the great 

hammerhead, are targeted in various fisheries, including semi-

industrial, artisanal, and recreational fisheries. Countries that fish 

for sharks include: Egypt, India, Iran, Oman, Saudi Arabia, Sudan, 

United Arab Emirates, and Yemen, where the probable or actual status of 

shark populations is unknown, and Maldives, Kenya, Mauritius, 

Seychelles, South Africa, and United Republic of Tanzania, where the 

actual status of shark population is presumed to be fully to 

overexploited (de Young, 2006). Analysis of fishery-independent data 

from the KwaZulu-Natal beach protection program off South Africa 

revealed declines in the catch rates of S. mokarran since the late 

1970s. Specifically, from 1978-2003, annual catch per unit effort 

(CPUE; in number of sharks per km net year) of S. mokarran declined by 

79 percent, from 0.44 to 0.09 (Dudley and Simpfendorfer, 2006). The 

results were statistically significant, with the slope of the linear

 

[[Page 24705]]

 

regression = -0.014, and the majority of the catch (greater than 64 

percent) being immature great hammerhead sharks (Dudley and 

Simpfendorfer, 2006).

    In Australian waters, sharks are caught by commercial, recreational 

and traditional fishers as targeted catch, retained catch, and bycatch. 

Almost all sharks landed in Australia are used for domestic 

consumption. According to Bensley et al. (2010), the annual commercial 

Australian shark catch from 1996 to 2006 ranged from about 8,600 mt to 

11,500 mt; however, the reporting of catch weights varied due to the 

state of processing (e.g., whole weight, processed weight, landed 

weight, etc.). Data from protective shark meshing programs off beaches 

in New South Wales (NSW) and Queensland suggest declines in hammerhead 

populations off the east coast of Australia. Over a 35-year period, the 

number of hammerheads caught per year in NSW beach nets decreased by 

more than 90 percent, from over 300 individuals in 1973 to less than 30 

in 2008, although the majority of the hammerhead catch was likely S. 

zygaena (Williamson, 2011). Similarly, data from the Queensland shark 

control program indicate declines of around 79 percent in hammerhead 

shark abundance between 1986 and 2010 (although it was estimated that 

S. lewini made up the majority of this catch) (Queensland Department of 

Employment, Economic Development and Innovation (QLD DEEDI), 2011). S. 

mokarran abundance in the nets fluctuated over the years, but remained 

below 20 individuals per year, until 2008/2009 when a peak of 33 

individuals was caught in the net (QLD DEEDI, 2011). Abundance has 

since declined by around 48 percent to 17 individuals in 2011/2012 (QLD 

DEEDI, 2011). In Australia's northwest marine region, Heupel and 

McAuley (2007) analyzed CPUE data from the northern shark fisheries for 

the period of 1996-2005 and reported hammerhead abundance declines of 

58-76 percent.

    Given the value and contribution of great hammerhead fins in the 

international fin trade and the evidence of historical and current 

fishing pressure and subsequent population declines, we conclude that 

the information in the petitions and in our files suggests that global 

fisheries are impacting great hammerhead shark populations to a degree 

that raises concerns of a risk of extinction.

 

 Inadequacy of Existing Regulatory Mechanisms

 

    The petitions assert that the existing international and domestic 

management measures of several nations have failed to adequately 

protect the great hammerhead or stop ongoing population declines and 

present information on some of the current national and international 

shark regulations. Although the WEG petition mentions the International 

Convention for the Conservation of Atlantic Tunas (ICCAT) 

Recommendation 10-08, prohibiting the retention, transshipment, 

landing, storing, or offering for sale any part or carcass of 

hammerhead sharks of the family Sphyrnidae (except for bonnethead 

shark), the petition states that ``these are merely recommendations and 

do not do enough to bind the relevant actors.'' On the contrary, the 

``relevant actors,'' of which we assume the petitioner is referring to 

ICCAT Contracting Parties, are bound to implement management measures 

consistent with achieving ICCAT recommendations under Article VIII of 

the ICCAT Convention. On August 29, 2011, we finalized the 

implementation of Recommendation 10-08 through passage of a final rule 

that prohibits the retention, possession, transshipment, landing, 

storing, selling or purchasing of oceanic whitetip sharks or scalloped, 

smooth, or great hammerheads by U.S. commercial highly migratory 

species (HMS) pelagic longline fishery and recreational fisheries for 

tunas, swordfish, and billfish in the Atlantic Ocean, including the 

Caribbean Sea and Gulf of Mexico (76 FR 53652; August 29, 2011). 

However, the exemption available to developing coastal States in this 

ICCAT recommendation, which allows them to retain hammerhead sharks for 

local consumption as long as no hammerhead parts enter international 

trade, is troubling. As this exception provides a lesser degree of 

protection for hammerhead sharks in some developing coastal States, it 

may be a cause for concern for great hammerhead populations in the 

Atlantic Ocean.

    In addition, the petitions note that there is limited international 

management of the great hammerhead shark, which is generally allowed to 

be harvested outside of U.S. waters and ICCAT fisheries. The other 

regional fishery management organizations (RFMOs) do not have any 

species-specific regulations for great hammerhead sharks, but have 

addressed the controversial practice of shark finning (which involves 

harvesting sharks, severing their fins and returning their remaining 

carcasses to the sea) by adopting shark finning bans to reduce the 

number of sharks killed solely for their fins. However, as the WEG 

petition points out, these finning bans are enforced by monitoring the 

fin-to-carcass weight ratio, with this ratio set at 5 percent (i.e., 

onboard fins cannot weigh more than 5 percent of the weight of sharks 

onboard, up to the first point of landing). In a study that looked at 

species-specific shark-fin-to-body-mass ratios, the great hammerhead 

shark had an average wet-fin-to-round-mass ratio of 1.96 percent (Biery 

and Pauly, 2012), much lower than the designated 5 percent. These 

results suggest that fishers of great hammerhead sharks would be able 

to land more fins than bodies and still pass inspection, essentially 

allowing them to continue the wasteful practice of shark finning at sea 

in these RFMO convention areas.

    Domestic laws and regulations for other nations may also be lacking 

in certain areas of the great hammerhead range. For example, in Central 

America and the Caribbean, Kyne et al. (2012) notes that due in large 

part to the number of autonomous countries found in this region, the 

management of shark species remains largely disjointed, with some 

countries lacking basic fisheries regulations, and weak enforcement of 

those they do have. Off West Africa, weak fisheries management has led 

to many of their fish stocks being declared fully exploited to 

overexploited (FAO, 2012). Environmental Justice Foundation (EJF) 

(2012) notes that even countries with stricter fishing regulations in 

this region lack the resources to provide effective or, for that 

matter, any enforcement, with some countries lacking basic monitoring 

systems. In addition, reports of illegal, unregulated, and unreported 

fishing are prevalent in the waters off West Africa and account for 

around 37 percent of the region's catch, the highest regional estimate 

of illegal fishing worldwide (Agnew et al., 2009; EJF, 2012). Illegal 

fishing is also common in the western central Pacific and eastern 

Indian Ocean (Agnew et al., 2009), with many reports of vessels being 

caught with illegal shark carcasses and fins onboard (Paul, 2009). As 

the NRDC petition notes, ``as recently as 2011, illegal fishing and 

finning of hammerhead sharks was documented in the Galapagos Marine 

Reserve,'' suggesting that illegal shark fishing may still be an 

impediment to conservation despite increasing international efforts to 

protect sharks. Without stricter fishery regulations or enforcement, 

there is concern that captures of great hammerhead sharks, both legal 

and illegal, may be kept, especially considering the high price that 

great hammerhead fins fetch in the international fin trade market. The 

information in the petitions and in our

 

[[Page 24706]]

 

files suggests that while there is increasing support for national and 

international shark conservation and regulation, the existing 

regulatory mechanisms in some portions of the S. mokarran range may be 

inadequate to address threats to the global great hammerhead 

population.

 

Other Natural or Manmade Factors

 

    The WEG petition contends that ``biological vulnerability'' in the 

form of long gestation periods, late maturity, and large size makes 

great hammerheads especially susceptible to overutilization. The 

species has low productivity (intrinsic rate of population increase per 

year = 0.070; Cort[eacute]s et al., 2012), which makes it generally 

vulnerable to depletion and slow to recover from overexploitation. In 

addition, both petitions mention the great hammerhead sharks' high 

capture mortality rate on bottom longline (BLL) gear. This high at-

vessel mortality makes the shark vulnerable to fishing pressure, with 

any capture of this species, regardless of whether the fishing is 

targeted or incidental, contributing to its fishing mortality. In the 

northwest Atlantic, at-vessel fishing mortality on BLL gear (averaged 

for all age groups) was estimated to be 93.8 percent for great 

hammerhead sharks (Morgan and Burgess, 2007). However, in an ecological 

risk assessment of 20 shark stocks, Cortes et al. (2012) found that the 

great hammerhead ranked 14th in terms of its susceptibility to pelagic 

longline fisheries in the Atlantic Ocean. This information suggests 

that the species' biological vulnerability (low productivity and high 

at-vessel mortality) may be a threat in certain fisheries, possibly 

contributing to an increased risk of extinction, but may not be a cause 

for concern in other fisheries.

 

Conclusion

 

    We conclude that the information in the petition and in our files 

suggests that fisheries, inadequate existing regulatory mechanisms, and 

other natural factors may be impacting great hammerhead shark 

populations to a degree that raises concerns of a risk of extinction, 

with evidence of population depletions throughout the entire range of 

the great hammerhead shark. We find that the WEG petition's discussion 

of the present and threatened destruction, modification, and 

curtailment of the great hammerhead's habitat and range due to growing 

human populations and both petitions' discussions of climate change 

threats to habitats do not constitute substantial information 

indicating that listing may be warranted. The petitioners fail to show 

if the great hammerhead shark is responding in a negative fashion to 

those specific threats. For example, neither petition provides 

evidence, nor is there information in our files, to indicate that 

hypoxic occurrences and dead zones, a result of growing human 

populations, urban pollution, and climate warming, negatively impact 

shark populations. In fact, shark abundance can be very high in dead 

zones (Driggers and Hoffmayer, personal communication, 2013). In 

addition, both petitions assert that the loss of coral reef habitat due 

to climate change puts great hammerheads at risk of extinction; 

however, great hammerhead sharks are highly migratory species and are 

not limited to reef habitats. Additionally, another interpretation of 

the information could be that as ocean temperatures warm, more adequate 

habitat for great hammerheads would become available as they are a 

tropical species. The WEG petition also does not provide substantial 

information indicating that listing may be warranted due to the 

presence of mercury, PCBs, and arsenic in the great hammerhead shark's 

environment. The WEG petition references studies that examined the 

concentrations of these metals and organic compounds in different shark 

species, but it does not provide information, nor is there information 

in the references or in our files, on the effects of these substances 

and concentrations on great hammerhead sharks. In fact, the petition 

quotes a reference, stating that ``scientists found that `[a]ll life-

history stages [of the great white shark] may be vulnerable to high 

body burdens of anthropogenic toxins; how these may impact the 

population is not known.' '' In addition, one of the petition's 

references, Storelli et al. (2003), states ``[i]t is hypothesed [sic] 

that the large size of elasmobranch liver provides a greater ability to 

eliminate organic toxicants than in other fishes.'' The reference also 

mentions that in marine mammals selenium has a detoxifying effect 

against mercury intoxication when the molar ratio between the two 

metals is close to one, and observed similar ratios in shark liver 

``indicating that this particular mechanism may also be valid for 

sharks'' (Storelli et al., 2003). We conclude that given the 

information in the petition, references, and in our files, the petition 

fails to show that the great hammerhead may be responding in a negative 

fashion to these proposed threats.

 

Summary of ESA Section 4(a)(1) Factors

 

    We conclude that the petitions present substantial scientific or 

commercial information indicating that the petitioned action may be 

warranted due to a combination of the following three ESA section 

4(a)(1) factors that may be causing or contributing to an increased 

risk of extinction for the great hammerhead shark: Overutilization for 

commercial, recreational, scientific, or educational purposes, 

inadequate existing regulatory mechanisms, and other natural factors. 

However, we conclude that the WEG petition does not present substantial 

scientific or commercial information indicating that the petitioned 

action may be warranted based on the remaining two ESA section 4(a)(1) 

factors: The present or threatened destruction, modification, or 

curtailment of its habitat or range; or disease or predation.

 

Petition Finding

 

    After reviewing the information contained in the petitions, as well 

as information readily available in our files, and based on the above 

analysis, we conclude that the petitions present substantial scientific 

information indicating that the petitioned action of listing the great 

hammerhead shark range-wide as threatened or endangered may be 

warranted. Therefore, in accordance with section 4(b)(3)(B) of the ESA 

and NMFS' implementing regulations (50 CFR 424.14(b)(2)), we will 

commence a status review of the species. During our status review, we 

will first determine whether the species is in danger of extinction 

(endangered) or likely to become so (threatened) throughout all or a 

significant portion of its range. If it is not, then we will consider 

whether any populations meet the DPS policy criteria, and if so, 

whether any of these are threatened or endangered throughout all or a 

significant portion of their ranges. We now initiate this review, and 

thus, the great hammerhead shark is considered to be a candidate 

species (69 FR 19975; April 15, 2004). Within 12 months of the receipt 

of the petition (December 21, 2013), we will make a finding as to 

whether listing the species (or any identified DPSs) as endangered or 

threatened is warranted as required by section 4(b)(3)(B) of the ESA. 

If listing the species (or any identified DPSs) 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 on 

whether the great hammerhead shark is endangered or

 

[[Page 24707]]

 

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 great 

hammerhead shark bycatch and retention in industrial, commercial, 

artisanal, and recreational fisheries worldwide; (5) historical and 

current data on great hammerhead shark discards in global fisheries; 

(6) data on the trade of great hammerhead 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 their 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.

 

We, NMFS, announce a 90-day finding on two petitions to list 

the great hammerhead shark (Sphyrna mokarran) range-wide or, in the 

alternative, the Northwest Atlantic distinct population segment (DPS) 

or any other identified DPSs as threatened or endangered under the 

Endangered Species Act (ESA), and to designate critical habitat. 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.

 

DATES: Information and comments on the subject action must be received 

by June 25, 2013.

 

ADDRESSES: You may submit comments, information, or data on this 

document, identified by the code NOAA-NMFS-2013-0046, by any of the 

following methods:

     Electronic Submissions: Submit all electronic comments via 

the Federal eRulemaking Portal. Go to www.regulations.gov/#!docketDetail;D=NOAA-NMFS-2013-0046, click the ``Comment Now!'' icon, 

complete the required fields, and enter or attach your comments.

     Mail: Submit written comments to Office of Protected 

Resources, NMFS, 1315 East-West Highway, Silver Spring, MD 20910.

     Fax: 301-713-4060, Attn: Maggie Miller.

    Instructions: 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 by NMFS. All comments received are a part of the 

public record and will generally be posted for public viewing on 

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. NMFS 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: Maggie Miller, NMFS, Office of 

Protected Resources, (301) 427-8403.

 

SUPPLEMENTARY INFORMATION: 

 

Background

 

    On December 21, 2012, we received a petition from WildEarth 

Guardians (WEG) to list the great hammerhead shark (Sphyrna mokarran) 

as threatened or endangered under the ESA throughout its entire range, 

or, as an alternative, to list any identified DPSs as threatened or 

endangered. The petitioners also requested that critical habitat be 

designated for the great hammerhead under the ESA. On March 19, 2013, 

we received a petition from Natural Resources Defense Council (NRDC) to 

list the northwest Atlantic DPS of great hammerhead shark as 

threatened, or, as an alternative, to list the great hammerhead shark 

range-wide as threatened, and to designate critical habitat. The joint 

U.S. Fish and Wildlife Service (USFWS)/NMFS Endangered Species Act 

Petition Management Guidance (1996) states that if we receive two 

petitions for the same species, the requests only differ in the 

requested status of the species, and a 90-day finding has not yet been 

made on the earlier petition, then the later petition will be combined 

with the earlier petition and a combined 90-day finding will be 

prepared. Since the initial petition requested listing of the species 

as threatened or endangered and the second petition only requested a 

threatened listing, and a finding has not been made on the initial 

petition, we have combined the WEG and NRDC petitions and this 90-day 

finding will address both. 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 that 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

 

[[Page 24702]]

 

conduct a comprehensive review of the best available scientific and 

commercial information. In such cases, we conclude the review with a 

finding as to whether, in fact, 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 more thorough review of the available 

information, as compared to the narrow scope of review at the 90-day 

stage, a finding that the ``petition presents substantial scientific or 

commercial information that the action may be warranted'' at this point 

does not predetermine 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-USFWS (jointly, ``the Services'') policy (DPS 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 

(ESA sections 3(6) and 3(20), respectively, 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 five section 4(a)(1) factors: (1) The 

present or threatened destruction, modification, or curtailment of 

habitat or range; (2) overutilization for commercial, recreational, 

scientific, or educational purposes; (3) disease or predation; (4) 

inadequacy of existing regulatory mechanisms; and (5) 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 the Services (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. 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 petition presents substantial 

information indicating the 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 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 it supports the 

petitioners' assertions. In other words, conclusive information 

indicating that 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 that 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 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

 

[[Page 24703]]

 

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 Hammerhead Shark

 

    The great hammerhead shark is a circumtropical species that lives 

in coastal-pelagic and semi-oceanic waters from latitudes of 40[deg] N 

to 35[deg] S (Compagno, 1984; Denham et al., 2007). It occurs over 

continental shelves as well as adjacent deep waters, and may also be 

found in coral reefs and lagoons (Compagno, 1984; Denham et al., 2007; 

Bester, n.d.). Great hammerhead sharks are highly mobile and seasonally 

migratory (Compagno, 1984; Denham et al., 2007; Hammerschlag et al., 

2011; Bester, n.d.). In the western Atlantic Ocean, the great 

hammerhead range extends from Massachusetts (although the species is 

rare north of North Carolina), in the United States, to Uruguay, 

including the Gulf of Mexico and Caribbean Sea. In the eastern 

Atlantic, it can be found from Morocco to Senegal, including in the 

Mediterranean Sea. The great hammerhead shark can also be found 

throughout the Indian Ocean and the Red Sea and in the Indo-Pacific 

region from Ryukyu Island south to New Caledonia and east to French 

Polynesia (Bester, n.d.). Distribution in the eastern Pacific Ocean 

extends from southern Baja California, including the Gulf of 

California, to Peru (Compagno, 1984).

    The general life history pattern of the great hammerhead shark is 

that of a long lived (oldest observed maximum age = 44 years; Piercy et 

al., 2010), large, and relatively slow growing species. The great 

hammerhead shark has a laterally expanded head that resembles a hammer, 

hence the common name ``hammerhead,'' and belongs to the Sphyrnidae 

family. The great hammerhead shark is the largest of the hammerheads, 

characterized by a nearly straight anterior margin of the head and 

median indentation in the center in adults, strongly serrated teeth, 

strongly falcate first dorsal and pelvic fins, and a high second dorsal 

fin with a concave rear margin (Compagno, 1984; Bester, n.d.). The body 

of the great hammerhead is fusiform, with the dorsal side colored dark 

brown to light grey or olive that shades to white on the ventral side 

(Compagno, 1984; Bester, n.d.). Fins of adult great hammerheads are 

uniform in color, while the tip of the second dorsal fin of juveniles 

may appear dusky (Bester, n.d.).

    The oldest aged great hammerhead sharks had lengths of 398 cm total 

length (TL) (female--44 years) and 379 cm TL (male--42 years) (Piercy 

et al., 2010), but they can reach lengths of over 610 cm TL (Compagno, 

1984). However, individuals greater than 400 cm TL are rare (Compagno, 

1984; Stevens and Lyle 1989), which Piercy et al. (2010) suggest may be 

attributed to growth overfishing. Estimates for size at maturity range 

from 234 to 269 cm TL for males and 210 to 300 cm TL for females 

(Compagno, 1984; Stevens and Lyle 1989). Male great hammerhead sharks 

have also been shown to grow faster than females (with a growth 

coefficient, k, of 0.16/year for males and 0.11/year for females) but 

reach a smaller asymptotic size (335 cm TL for males versus 389 cm TL 

for females) (Piercy et al., 2010).

    The great hammerhead shark is viviparous (i.e., give birth to live 

young), with a gestation period of 10-11 months, and likely breeds 

every other year (Stevens and Lyle, 1989). Litter sizes range from 6 to 

42 live pups (Compagno, 1984; Stevens and Lyle, 1989). Length at birth 

estimates for great hammerheads range from 50-70 cm TL (Compagno, 1984; 

Stevens and Lyle, 1989).

    The great hammerhead shark is a high trophic level predator 

(Cort[eacute]s, 1999) and opportunistic feeder, with a diet that 

includes a wide variety of teleosts, cephalopods, and crustaceans, with 

a preference for stingrays (Compagno, 1984; Denham et al., 2007).

 

Analysis of Petition and Information Readily Available in NMFS Files

 

    We evaluated the information provided in the petition and readily 

available in our files to determine if the petitions presented 

substantial scientific or commercial information indicating that the 

petitioned actions may be warranted. The petitions contain information 

on the species, including the taxonomy, species description, geographic 

distribution, and habitat, with some information on population status 

and trends in certain locations, and factors contributing to the 

species' decline. The petitions state that commercial fishing, both 

targeted and bycatch, is the primary threat to the great hammerhead 

shark. The petitioners also assert that current habitat destruction, 

deposition of pollutants, lack of adequate regulatory mechanisms 

nationally and worldwide, global climate warming, as well the species' 

biological constraints, increase the susceptibility of the great 

hammerhead shark to extinction.

    According to the WEG petition, all five causal factors in section 

4(a)(1) of the ESA are adversely affecting the continued existence of 

the great hammerhead shark: (A) The present or threatened destruction, 

modification, or curtailment of its habitat or range; (B) 

overutilization for commercial, recreational, scientific, or 

educational purposes; (C) disease or predation; (D) inadequacy of 

existing regulatory mechanisms; and (E) other natural or manmade 

factors affecting its continued existence. The focus of the NRDC 

petition is mainly on the northwest Atlantic population and it 

identified the threats of: (B) overutilization for commercial, 

recreational, scientific, or educational purposes; (D) inadequacy of 

existing regulatory mechanisms; and (E) other natural or manmade 

factors affecting its continued existence. In the following sections, 

we use the information presented in the petition and in our files to 

determine whether the petitioned action may be warranted. If requested 

to list a global population and, alternatively, a DPS, we first 

determine if the petition presents substantial information that the 

petitioned action is warranted for the global population. If it does, 

then we make a positive finding on the petition and will revisit the 

question of DPSs during a status review, if necessary. If the petition 

does not present substantial information that the global population may 

warrant listing, and it has requested that we list any populations of 

the species as threatened or endangered, then we consider whether the 

petition provides substantial information that the requested 

population(s) may qualify as DPSs under the discreteness and 

significance criteria of our joint DPS Policy, and if listing any of 

those DPSs may be warranted. We summarize our analysis and conclusions 

regarding the information presented by the petitioners and in our files 

on the specific ESA section 4(a)(1) factors that we find may be 

affecting the species' risk of global extinction below.

 

Overutilization for Commercial, Recreational, Scientific, or 

Educational Purposes

 

    Information from the petitions and in our files suggests that the 

primary threat to the great hammerhead shark is from fisheries. Great 

hammerhead sharks are both targeted and taken as bycatch in many global 

fisheries (e.g., bottom and pelagic longlines, coastal gillnet 

fisheries, artisanal fisheries). Because of their large fins with high 

fin needle

 

[[Page 24704]]

 

content (a gelatinous product used to make shark fin soup), hammerheads 

fetch a high commercial value in the Asian shark fin trade (Abercrombie 

et al., 2005). However, the WEG petition overstates the contribution of 

great hammerheads in the Hong Kong fin trade market by presenting 

information on the trade of scalloped, smooth, and great hammerhead 

fins together. According to a genetic study that examined the 

concordance between assigned Hong Kong market categories and the 

corresponding fins, the great hammerhead market category ``Gu pian'' 

had an 88 percent concordance rate, indicating that traders are able to 

accurately identify and separate great hammerhead fins from the other 

hammerhead species (Abercrombie et al., 2005; Clarke et al., 2006a). As 

such, here we provide the information on a finer scale level (down to 

the species level) to evaluate the extent that the fin trade may 

contribute to the overutilization of the great hammerhead shark. 

According to Clarke et al. (2006a), S. mokarran is estimated to 

comprise approximately 1.5 percent of the total fins traded annually in 

the Hong Kong fin market. As mentioned above, great hammerhead fins are 

primarily traded under the ``Gu pian'' market category, where the 

market value for the average, wholesale, unprocessed fin is around 

$135/kg, the most for any of the hammerhead fins (Abercrombie et al., 

2005). Extrapolating the fin data to numbers of sharks, Clarke et al. 

(2006b) estimates that around 375,000 (95 percent confidence interval = 

130,000-1.1 million) individuals of this species (equivalent to a 

biomass of around 21,000 metric tons, (mt)) are traded annually in the 

Hong Kong fin market. Given their high price in the Hong Kong market, 

there is concern that many great hammerheads caught as incidental catch 

may be kept for the fin trade as opposed to released alive.

    In the United States, great hammerhead sharks are mainly caught as 

bycatch in commercial longline and net fisheries and by recreational 

fishers using rod and reel. A recent stock assessment by Jiao et al. 

(2011) used a Bayesian hierarchical approach to assess the data-poor 

hammerhead species and found that the northwestern Atlantic and Gulf of 

Mexico great hammerhead population likely became overfished in the mid-

1980s and experienced overfishing periodically from 1983 to 1997. 

However, after 2001, the models showed that the risk of overfishing was 

very low and that this population is probably still overfished but no 

longer experiencing overfishing (Jiao et al., 2011), likely a result of 

the implementation of stronger fishery management regulations since the 

early 1990s. Under the Magnuson-Stevens Fishery Conservation and 

Management Act (MSA), the term ``overfishing'' is defined as occurring 

when a stock experiences ``a level of fishing mortality that 

jeopardizes the capacity of a stock or stock complex to produce MSY 

[maximum sustainable yield] on a continuing basis'' (50 CFR 600.310). 

An ``overfished'' stock is defined as a stock whose biomass has 

declined below a level that jeopardizes the capacity of the stock to 

produce MSY on a continuing basis (50 CFR 600.310). However, it is 

important to note that these MSA classifications are based on different 

criteria (i.e., achieving MSY) than threatened or endangered statuses 

under the ESA. As such, ``overfished'' and ``overfishing'' 

classifications do not necessarily indicate that a species may warrant 

listing because they do not evaluate a species' extinction risk. 

However, they are relevant considerations for us to consider when we 

evaluate potential threats to the species from overutilization for 

commercial or recreational purposes.

    In Central America and the Caribbean, there are very little data on 

great hammerhead catches. The WEG petition references Denham et al. 

(2007) which states that hammerheads were heavily fished by longlines 

off the coast of Belize in the 1980s and early 1990s, leading to an 

observed decline in the abundance and size of hammerheads and prompting 

a halt in the Belize-based shark fishery. Fishing pressure on 

hammerheads still continues as a result of Guatemalan fishermen 

entering Belizean waters (Denham et al., 2007). However, catch records 

from the Cuban directed shark fishery show a small increase in the mean 

size of great hammerheads since 1992, suggesting partial recovery of 

the species in this region (Denham et al. 2007).

    The WEG petition also references a study (Feretti et al., 2008) 

that indicated that the population of smooth, scalloped, and great 

hammerheads in the Mediterranean Sea has experienced a greater than 99 

percent decline in abundance and biomass; however, the authors of this 

study note that only Sphyrna zygaena (smooth hammerhead) was assessed 

because the other hammerhead species occurred only sporadically in 

historical records. As such, this is not an appropriate index of the 

abundance of the other hammerhead species in the Mediterranean Sea and 

does not indicate overutilization of the great hammerhead shark in this 

region.

    In the Eastern Atlantic, off West Africa, the WEG petition states 

that the ``great hammerhead population is believed to have fallen 80 

percent as a result of unmanaged and unmonitored fisheries,'' but we 

could not verify the original source of this statistic. Data from the 

European pelagic freezer-trawler fishery that operates off Mauritania 

shows hammerhead species, including S. mokarran, constitute a 

significant component of the fishery's bycatch. Between 2001 and 2005, 

42 percent of the retained pelagic megafauna bycatch from over 1,400 

freezer-trawl sets consisted of hammerhead species, with around 75 

percent of the hammerhead catch juveniles of 0.50-1.40 m in length 

(Zeeberg et al., 2006). According to Denham et al. (2007), the sub-

regional plan of action for sharks of West Africa identified S. 

mokarran as particularly threatened in the region, with a noticeable 

decline in the population and collapse of landings. Citing unpublished 

data and anecdotal evidence, Denham et al. (2007) suggests that S. 

mokarran is ``almost extirpated'' from waters off Mauritania to Angola 

after previously being abundant in these areas in the early 1980s. The 

growth of fisheries targeting sharks in this region for the lucrative 

fin trade has likely contributed to the great hammerhead decline. By 

the 1980s, many fishers were specializing in catching sharks (Denham et 

al., 2007), with some artisanal fisheries in West Africa specifically 

specializing in catching sphyrnid species (CITES, 2010).

    In the Indian Ocean, pelagic sharks, including the great 

hammerhead, are targeted in various fisheries, including semi-

industrial, artisanal, and recreational fisheries. Countries that fish 

for sharks include: Egypt, India, Iran, Oman, Saudi Arabia, Sudan, 

United Arab Emirates, and Yemen, where the probable or actual status of 

shark populations is unknown, and Maldives, Kenya, Mauritius, 

Seychelles, South Africa, and United Republic of Tanzania, where the 

actual status of shark population is presumed to be fully to 

overexploited (de Young, 2006). Analysis of fishery-independent data 

from the KwaZulu-Natal beach protection program off South Africa 

revealed declines in the catch rates of S. mokarran since the late 

1970s. Specifically, from 1978-2003, annual catch per unit effort 

(CPUE; in number of sharks per km net year) of S. mokarran declined by 

79 percent, from 0.44 to 0.09 (Dudley and Simpfendorfer, 2006). The 

results were statistically significant, with the slope of the linear

 

[[Page 24705]]

 

regression = -0.014, and the majority of the catch (greater than 64 

percent) being immature great hammerhead sharks (Dudley and 

Simpfendorfer, 2006).

    In Australian waters, sharks are caught by commercial, recreational 

and traditional fishers as targeted catch, retained catch, and bycatch. 

Almost all sharks landed in Australia are used for domestic 

consumption. According to Bensley et al. (2010), the annual commercial 

Australian shark catch from 1996 to 2006 ranged from about 8,600 mt to 

11,500 mt; however, the reporting of catch weights varied due to the 

state of processing (e.g., whole weight, processed weight, landed 

weight, etc.). Data from protective shark meshing programs off beaches 

in New South Wales (NSW) and Queensland suggest declines in hammerhead 

populations off the east coast of Australia. Over a 35-year period, the 

number of hammerheads caught per year in NSW beach nets decreased by 

more than 90 percent, from over 300 individuals in 1973 to less than 30 

in 2008, although the majority of the hammerhead catch was likely S. 

zygaena (Williamson, 2011). Similarly, data from the Queensland shark 

control program indicate declines of around 79 percent in hammerhead 

shark abundance between 1986 and 2010 (although it was estimated that 

S. lewini made up the majority of this catch) (Queensland Department of 

Employment, Economic Development and Innovation (QLD DEEDI), 2011). S. 

mokarran abundance in the nets fluctuated over the years, but remained 

below 20 individuals per year, until 2008/2009 when a peak of 33 

individuals was caught in the net (QLD DEEDI, 2011). Abundance has 

since declined by around 48 percent to 17 individuals in 2011/2012 (QLD 

DEEDI, 2011). In Australia's northwest marine region, Heupel and 

McAuley (2007) analyzed CPUE data from the northern shark fisheries for 

the period of 1996-2005 and reported hammerhead abundance declines of 

58-76 percent.

    Given the value and contribution of great hammerhead fins in the 

international fin trade and the evidence of historical and current 

fishing pressure and subsequent population declines, we conclude that 

the information in the petitions and in our files suggests that global 

fisheries are impacting great hammerhead shark populations to a degree 

that raises concerns of a risk of extinction.

 

 Inadequacy of Existing Regulatory Mechanisms

 

    The petitions assert that the existing international and domestic 

management measures of several nations have failed to adequately 

protect the great hammerhead or stop ongoing population declines and 

present information on some of the current national and international 

shark regulations. Although the WEG petition mentions the International 

Convention for the Conservation of Atlantic Tunas (ICCAT) 

Recommendation 10-08, prohibiting the retention, transshipment, 

landing, storing, or offering for sale any part or carcass of 

hammerhead sharks of the family Sphyrnidae (except for bonnethead 

shark), the petition states that ``these are merely recommendations and 

do not do enough to bind the relevant actors.'' On the contrary, the 

``relevant actors,'' of which we assume the petitioner is referring to 

ICCAT Contracting Parties, are bound to implement management measures 

consistent with achieving ICCAT recommendations under Article VIII of 

the ICCAT Convention. On August 29, 2011, we finalized the 

implementation of Recommendation 10-08 through passage of a final rule 

that prohibits the retention, possession, transshipment, landing, 

storing, selling or purchasing of oceanic whitetip sharks or scalloped, 

smooth, or great hammerheads by U.S. commercial highly migratory 

species (HMS) pelagic longline fishery and recreational fisheries for 

tunas, swordfish, and billfish in the Atlantic Ocean, including the 

Caribbean Sea and Gulf of Mexico (76 FR 53652; August 29, 2011). 

However, the exemption available to developing coastal States in this 

ICCAT recommendation, which allows them to retain hammerhead sharks for 

local consumption as long as no hammerhead parts enter international 

trade, is troubling. As this exception provides a lesser degree of 

protection for hammerhead sharks in some developing coastal States, it 

may be a cause for concern for great hammerhead populations in the 

Atlantic Ocean.

    In addition, the petitions note that there is limited international 

management of the great hammerhead shark, which is generally allowed to 

be harvested outside of U.S. waters and ICCAT fisheries. The other 

regional fishery management organizations (RFMOs) do not have any 

species-specific regulations for great hammerhead sharks, but have 

addressed the controversial practice of shark finning (which involves 

harvesting sharks, severing their fins and returning their remaining 

carcasses to the sea) by adopting shark finning bans to reduce the 

number of sharks killed solely for their fins. However, as the WEG 

petition points out, these finning bans are enforced by monitoring the 

fin-to-carcass weight ratio, with this ratio set at 5 percent (i.e., 

onboard fins cannot weigh more than 5 percent of the weight of sharks 

onboard, up to the first point of landing). In a study that looked at 

species-specific shark-fin-to-body-mass ratios, the great hammerhead 

shark had an average wet-fin-to-round-mass ratio of 1.96 percent (Biery 

and Pauly, 2012), much lower than the designated 5 percent. These 

results suggest that fishers of great hammerhead sharks would be able 

to land more fins than bodies and still pass inspection, essentially 

allowing them to continue the wasteful practice of shark finning at sea 

in these RFMO convention areas.

    Domestic laws and regulations for other nations may also be lacking 

in certain areas of the great hammerhead range. For example, in Central 

America and the Caribbean, Kyne et al. (2012) notes that due in large 

part to the number of autonomous countries found in this region, the 

management of shark species remains largely disjointed, with some 

countries lacking basic fisheries regulations, and weak enforcement of 

those they do have. Off West Africa, weak fisheries management has led 

to many of their fish stocks being declared fully exploited to 

overexploited (FAO, 2012). Environmental Justice Foundation (EJF) 

(2012) notes that even countries with stricter fishing regulations in 

this region lack the resources to provide effective or, for that 

matter, any enforcement, with some countries lacking basic monitoring 

systems. In addition, reports of illegal, unregulated, and unreported 

fishing are prevalent in the waters off West Africa and account for 

around 37 percent of the region's catch, the highest regional estimate 

of illegal fishing worldwide (Agnew et al., 2009; EJF, 2012). Illegal 

fishing is also common in the western central Pacific and eastern 

Indian Ocean (Agnew et al., 2009), with many reports of vessels being 

caught with illegal shark carcasses and fins onboard (Paul, 2009). As 

the NRDC petition notes, ``as recently as 2011, illegal fishing and 

finning of hammerhead sharks was documented in the Galapagos Marine 

Reserve,'' suggesting that illegal shark fishing may still be an 

impediment to conservation despite increasing international efforts to 

protect sharks. Without stricter fishery regulations or enforcement, 

there is concern that captures of great hammerhead sharks, both legal 

and illegal, may be kept, especially considering the high price that 

great hammerhead fins fetch in the international fin trade market. The 

information in the petitions and in our

 

[[Page 24706]]

 

files suggests that while there is increasing support for national and 

international shark conservation and regulation, the existing 

regulatory mechanisms in some portions of the S. mokarran range may be 

inadequate to address threats to the global great hammerhead 

population.

 

Other Natural or Manmade Factors

 

    The WEG petition contends that ``biological vulnerability'' in the 

form of long gestation periods, late maturity, and large size makes 

great hammerheads especially susceptible to overutilization. The 

species has low productivity (intrinsic rate of population increase per 

year = 0.070; Cort[eacute]s et al., 2012), which makes it generally 

vulnerable to depletion and slow to recover from overexploitation. In 

addition, both petitions mention the great hammerhead sharks' high 

capture mortality rate on bottom longline (BLL) gear. This high at-

vessel mortality makes the shark vulnerable to fishing pressure, with 

any capture of this species, regardless of whether the fishing is 

targeted or incidental, contributing to its fishing mortality. In the 

northwest Atlantic, at-vessel fishing mortality on BLL gear (averaged 

for all age groups) was estimated to be 93.8 percent for great 

hammerhead sharks (Morgan and Burgess, 2007). However, in an ecological 

risk assessment of 20 shark stocks, Cortes et al. (2012) found that the 

great hammerhead ranked 14th in terms of its susceptibility to pelagic 

longline fisheries in the Atlantic Ocean. This information suggests 

that the species' biological vulnerability (low productivity and high 

at-vessel mortality) may be a threat in certain fisheries, possibly 

contributing to an increased risk of extinction, but may not be a cause 

for concern in other fisheries.

 

Conclusion

 

    We conclude that the information in the petition and in our files 

suggests that fisheries, inadequate existing regulatory mechanisms, and 

other natural factors may be impacting great hammerhead shark 

populations to a degree that raises concerns of a risk of extinction, 

with evidence of population depletions throughout the entire range of 

the great hammerhead shark. We find that the WEG petition's discussion 

of the present and threatened destruction, modification, and 

curtailment of the great hammerhead's habitat and range due to growing 

human populations and both petitions' discussions of climate change 

threats to habitats do not constitute substantial information 

indicating that listing may be warranted. The petitioners fail to show 

if the great hammerhead shark is responding in a negative fashion to 

those specific threats. For example, neither petition provides 

evidence, nor is there information in our files, to indicate that 

hypoxic occurrences and dead zones, a result of growing human 

populations, urban pollution, and climate warming, negatively impact 

shark populations. In fact, shark abundance can be very high in dead 

zones (Driggers and Hoffmayer, personal communication, 2013). In 

addition, both petitions assert that the loss of coral reef habitat due 

to climate change puts great hammerheads at risk of extinction; 

however, great hammerhead sharks are highly migratory species and are 

not limited to reef habitats. Additionally, another interpretation of 

the information could be that as ocean temperatures warm, more adequate 

habitat for great hammerheads would become available as they are a 

tropical species. The WEG petition also does not provide substantial 

information indicating that listing may be warranted due to the 

presence of mercury, PCBs, and arsenic in the great hammerhead shark's 

environment. The WEG petition references studies that examined the 

concentrations of these metals and organic compounds in different shark 

species, but it does not provide information, nor is there information 

in the references or in our files, on the effects of these substances 

and concentrations on great hammerhead sharks. In fact, the petition 

quotes a reference, stating that ``scientists found that `[a]ll life-

history stages [of the great white shark] may be vulnerable to high 

body burdens of anthropogenic toxins; how these may impact the 

population is not known.' '' In addition, one of the petition's 

references, Storelli et al. (2003), states ``[i]t is hypothesed [sic] 

that the large size of elasmobranch liver provides a greater ability to 

eliminate organic toxicants than in other fishes.'' The reference also 

mentions that in marine mammals selenium has a detoxifying effect 

against mercury intoxication when the molar ratio between the two 

metals is close to one, and observed similar ratios in shark liver 

``indicating that this particular mechanism may also be valid for 

sharks'' (Storelli et al., 2003). We conclude that given the 

information in the petition, references, and in our files, the petition 

fails to show that the great hammerhead may be responding in a negative 

fashion to these proposed threats.

 

Summary of ESA Section 4(a)(1) Factors

 

    We conclude that the petitions present substantial scientific or 

commercial information indicating that the petitioned action may be 

warranted due to a combination of the following three ESA section 

4(a)(1) factors that may be causing or contributing to an increased 

risk of extinction for the great hammerhead shark: Overutilization for 

commercial, recreational, scientific, or educational purposes, 

inadequate existing regulatory mechanisms, and other natural factors. 

However, we conclude that the WEG petition does not present substantial 

scientific or commercial information indicating that the petitioned 

action may be warranted based on the remaining two ESA section 4(a)(1) 

factors: The present or threatened destruction, modification, or 

curtailment of its habitat or range; or disease or predation.

 

Petition Finding

 

    After reviewing the information contained in the petitions, as well 

as information readily available in our files, and based on the above 

analysis, we conclude that the petitions present substantial scientific 

information indicating that the petitioned action of listing the great 

hammerhead shark range-wide as threatened or endangered may be 

warranted. Therefore, in accordance with section 4(b)(3)(B) of the ESA 

and NMFS' implementing regulations (50 CFR 424.14(b)(2)), we will 

commence a status review of the species. During our status review, we 

will first determine whether the species is in danger of extinction 

(endangered) or likely to become so (threatened) throughout all or a 

significant portion of its range. If it is not, then we will consider 

whether any populations meet the DPS policy criteria, and if so, 

whether any of these are threatened or endangered throughout all or a 

significant portion of their ranges. We now initiate this review, and 

thus, the great hammerhead shark is considered to be a candidate 

species (69 FR 19975; April 15, 2004). Within 12 months of the receipt 

of the petition (December 21, 2013), we will make a finding as to 

whether listing the species (or any identified DPSs) as endangered or 

threatened is warranted as required by section 4(b)(3)(B) of the ESA. 

If listing the species (or any identified DPSs) 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 on 

whether the great hammerhead shark is endangered or

 

[[Page 24707]]

 

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 great 

hammerhead shark bycatch and retention in industrial, commercial, 

artisanal, and recreational fisheries worldwide; (5) historical and 

current data on great hammerhead shark discards in global fisheries; 

(6) data on the trade of great hammerhead 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 their 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.

 

We, NMFS, announce a 90-day finding on two petitions to list 

the great hammerhead shark (Sphyrna mokarran) range-wide or, in the 

alternative, the Northwest Atlantic distinct population segment (DPS) 

or any other identified DPSs as threatened or endangered under the 

Endangered Species Act (ESA), and to designate critical habitat. 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.

 

DATES: Information and comments on the subject action must be received 

by June 25, 2013.

 

ADDRESSES: You may submit comments, information, or data on this 

document, identified by the code NOAA-NMFS-2013-0046, by any of the 

following methods:

     Electronic Submissions: Submit all electronic comments via 

the Federal eRulemaking Portal. Go to www.regulations.gov/#!docketDetail;D=NOAA-NMFS-2013-0046, click the ``Comment Now!'' icon, 

complete the required fields, and enter or attach your comments.

     Mail: Submit written comments to Office of Protected 

Resources, NMFS, 1315 East-West Highway, Silver Spring, MD 20910.

     Fax: 301-713-4060, Attn: Maggie Miller.

    Instructions: 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 by NMFS. All comments received are a part of the 

public record and will generally be posted for public viewing on 

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. NMFS 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: Maggie Miller, NMFS, Office of 

Protected Resources, (301) 427-8403.

 

SUPPLEMENTARY INFORMATION: 

 

Background

 

    On December 21, 2012, we received a petition from WildEarth 

Guardians (WEG) to list the great hammerhead shark (Sphyrna mokarran) 

as threatened or endangered under the ESA throughout its entire range, 

or, as an alternative, to list any identified DPSs as threatened or 

endangered. The petitioners also requested that critical habitat be 

designated for the great hammerhead under the ESA. On March 19, 2013, 

we received a petition from Natural Resources Defense Council (NRDC) to 

list the northwest Atlantic DPS of great hammerhead shark as 

threatened, or, as an alternative, to list the great hammerhead shark 

range-wide as threatened, and to designate critical habitat. The joint 

U.S. Fish and Wildlife Service (USFWS)/NMFS Endangered Species Act 

Petition Management Guidance (1996) states that if we receive two 

petitions for the same species, the requests only differ in the 

requested status of the species, and a 90-day finding has not yet been 

made on the earlier petition, then the later petition will be combined 

with the earlier petition and a combined 90-day finding will be 

prepared. Since the initial petition requested listing of the species 

as threatened or endangered and the second petition only requested a 

threatened listing, and a finding has not been made on the initial 

petition, we have combined the WEG and NRDC petitions and this 90-day 

finding will address both. 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 that 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

 

[[Page 24702]]

 

conduct a comprehensive review of the best available scientific and 

commercial information. In such cases, we conclude the review with a 

finding as to whether, in fact, 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 more thorough review of the available 

information, as compared to the narrow scope of review at the 90-day 

stage, a finding that the ``petition presents substantial scientific or 

commercial information that the action may be warranted'' at this point 

does not predetermine 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-USFWS (jointly, ``the Services'') policy (DPS 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 

(ESA sections 3(6) and 3(20), respectively, 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 five section 4(a)(1) factors: (1) The 

present or threatened destruction, modification, or curtailment of 

habitat or range; (2) overutilization for commercial, recreational, 

scientific, or educational purposes; (3) disease or predation; (4) 

inadequacy of existing regulatory mechanisms; and (5) 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 the Services (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. 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 petition presents substantial 

information indicating the 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 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 it supports the 

petitioners' assertions. In other words, conclusive information 

indicating that 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 that 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 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

 

[[Page 24703]]

 

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 Hammerhead Shark

 

    The great hammerhead shark is a circumtropical species that lives 

in coastal-pelagic and semi-oceanic waters from latitudes of 40[deg] N 

to 35[deg] S (Compagno, 1984; Denham et al., 2007). It occurs over 

continental shelves as well as adjacent deep waters, and may also be 

found in coral reefs and lagoons (Compagno, 1984; Denham et al., 2007; 

Bester, n.d.). Great hammerhead sharks are highly mobile and seasonally 

migratory (Compagno, 1984; Denham et al., 2007; Hammerschlag et al., 

2011; Bester, n.d.). In the western Atlantic Ocean, the great 

hammerhead range extends from Massachusetts (although the species is 

rare north of North Carolina), in the United States, to Uruguay, 

including the Gulf of Mexico and Caribbean Sea. In the eastern 

Atlantic, it can be found from Morocco to Senegal, including in the 

Mediterranean Sea. The great hammerhead shark can also be found 

throughout the Indian Ocean and the Red Sea and in the Indo-Pacific 

region from Ryukyu Island south to New Caledonia and east to French 

Polynesia (Bester, n.d.). Distribution in the eastern Pacific Ocean 

extends from southern Baja California, including the Gulf of 

California, to Peru (Compagno, 1984).

    The general life history pattern of the great hammerhead shark is 

that of a long lived (oldest observed maximum age = 44 years; Piercy et 

al., 2010), large, and relatively slow growing species. The great 

hammerhead shark has a laterally expanded head that resembles a hammer, 

hence the common name ``hammerhead,'' and belongs to the Sphyrnidae 

family. The great hammerhead shark is the largest of the hammerheads, 

characterized by a nearly straight anterior margin of the head and 

median indentation in the center in adults, strongly serrated teeth, 

strongly falcate first dorsal and pelvic fins, and a high second dorsal 

fin with a concave rear margin (Compagno, 1984; Bester, n.d.). The body 

of the great hammerhead is fusiform, with the dorsal side colored dark 

brown to light grey or olive that shades to white on the ventral side 

(Compagno, 1984; Bester, n.d.). Fins of adult great hammerheads are 

uniform in color, while the tip of the second dorsal fin of juveniles 

may appear dusky (Bester, n.d.).

    The oldest aged great hammerhead sharks had lengths of 398 cm total 

length (TL) (female--44 years) and 379 cm TL (male--42 years) (Piercy 

et al., 2010), but they can reach lengths of over 610 cm TL (Compagno, 

1984). However, individuals greater than 400 cm TL are rare (Compagno, 

1984; Stevens and Lyle 1989), which Piercy et al. (2010) suggest may be 

attributed to growth overfishing. Estimates for size at maturity range 

from 234 to 269 cm TL for males and 210 to 300 cm TL for females 

(Compagno, 1984; Stevens and Lyle 1989). Male great hammerhead sharks 

have also been shown to grow faster than females (with a growth 

coefficient, k, of 0.16/year for males and 0.11/year for females) but 

reach a smaller asymptotic size (335 cm TL for males versus 389 cm TL 

for females) (Piercy et al., 2010).

    The great hammerhead shark is viviparous (i.e., give birth to live 

young), with a gestation period of 10-11 months, and likely breeds 

every other year (Stevens and Lyle, 1989). Litter sizes range from 6 to 

42 live pups (Compagno, 1984; Stevens and Lyle, 1989). Length at birth 

estimates for great hammerheads range from 50-70 cm TL (Compagno, 1984; 

Stevens and Lyle, 1989).

    The great hammerhead shark is a high trophic level predator 

(Cort[eacute]s, 1999) and opportunistic feeder, with a diet that 

includes a wide variety of teleosts, cephalopods, and crustaceans, with 

a preference for stingrays (Compagno, 1984; Denham et al., 2007).

 

Analysis of Petition and Information Readily Available in NMFS Files

 

    We evaluated the information provided in the petition and readily 

available in our files to determine if the petitions presented 

substantial scientific or commercial information indicating that the 

petitioned actions may be warranted. The petitions contain information 

on the species, including the taxonomy, species description, geographic 

distribution, and habitat, with some information on population status 

and trends in certain locations, and factors contributing to the 

species' decline. The petitions state that commercial fishing, both 

targeted and bycatch, is the primary threat to the great hammerhead 

shark. The petitioners also assert that current habitat destruction, 

deposition of pollutants, lack of adequate regulatory mechanisms 

nationally and worldwide, global climate warming, as well the species' 

biological constraints, increase the susceptibility of the great 

hammerhead shark to extinction.

    According to the WEG petition, all five causal factors in section 

4(a)(1) of the ESA are adversely affecting the continued existence of 

the great hammerhead shark: (A) The present or threatened destruction, 

modification, or curtailment of its habitat or range; (B) 

overutilization for commercial, recreational, scientific, or 

educational purposes; (C) disease or predation; (D) inadequacy of 

existing regulatory mechanisms; and (E) other natural or manmade 

factors affecting its continued existence. The focus of the NRDC 

petition is mainly on the northwest Atlantic population and it 

identified the threats of: (B) overutilization for commercial, 

recreational, scientific, or educational purposes; (D) inadequacy of 

existing regulatory mechanisms; and (E) other natural or manmade 

factors affecting its continued existence. In the following sections, 

we use the information presented in the petition and in our files to 

determine whether the petitioned action may be warranted. If requested 

to list a global population and, alternatively, a DPS, we first 

determine if the petition presents substantial information that the 

petitioned action is warranted for the global population. If it does, 

then we make a positive finding on the petition and will revisit the 

question of DPSs during a status review, if necessary. If the petition 

does not present substantial information that the global population may 

warrant listing, and it has requested that we list any populations of 

the species as threatened or endangered, then we consider whether the 

petition provides substantial information that the requested 

population(s) may qualify as DPSs under the discreteness and 

significance criteria of our joint DPS Policy, and if listing any of 

those DPSs may be warranted. We summarize our analysis and conclusions 

regarding the information presented by the petitioners and in our files 

on the specific ESA section 4(a)(1) factors that we find may be 

affecting the species' risk of global extinction below.

 

Overutilization for Commercial, Recreational, Scientific, or 

Educational Purposes

 

    Information from the petitions and in our files suggests that the 

primary threat to the great hammerhead shark is from fisheries. Great 

hammerhead sharks are both targeted and taken as bycatch in many global 

fisheries (e.g., bottom and pelagic longlines, coastal gillnet 

fisheries, artisanal fisheries). Because of their large fins with high 

fin needle

 

[[Page 24704]]

 

content (a gelatinous product used to make shark fin soup), hammerheads 

fetch a high commercial value in the Asian shark fin trade (Abercrombie 

et al., 2005). However, the WEG petition overstates the contribution of 

great hammerheads in the Hong Kong fin trade market by presenting 

information on the trade of scalloped, smooth, and great hammerhead 

fins together. According to a genetic study that examined the 

concordance between assigned Hong Kong market categories and the 

corresponding fins, the great hammerhead market category ``Gu pian'' 

had an 88 percent concordance rate, indicating that traders are able to 

accurately identify and separate great hammerhead fins from the other 

hammerhead species (Abercrombie et al., 2005; Clarke et al., 2006a). As 

such, here we provide the information on a finer scale level (down to 

the species level) to evaluate the extent that the fin trade may 

contribute to the overutilization of the great hammerhead shark. 

According to Clarke et al. (2006a), S. mokarran is estimated to 

comprise approximately 1.5 percent of the total fins traded annually in 

the Hong Kong fin market. As mentioned above, great hammerhead fins are 

primarily traded under the ``Gu pian'' market category, where the 

market value for the average, wholesale, unprocessed fin is around 

$135/kg, the most for any of the hammerhead fins (Abercrombie et al., 

2005). Extrapolating the fin data to numbers of sharks, Clarke et al. 

(2006b) estimates that around 375,000 (95 percent confidence interval = 

130,000-1.1 million) individuals of this species (equivalent to a 

biomass of around 21,000 metric tons, (mt)) are traded annually in the 

Hong Kong fin market. Given their high price in the Hong Kong market, 

there is concern that many great hammerheads caught as incidental catch 

may be kept for the fin trade as opposed to released alive.

    In the United States, great hammerhead sharks are mainly caught as 

bycatch in commercial longline and net fisheries and by recreational 

fishers using rod and reel. A recent stock assessment by Jiao et al. 

(2011) used a Bayesian hierarchical approach to assess the data-poor 

hammerhead species and found that the northwestern Atlantic and Gulf of 

Mexico great hammerhead population likely became overfished in the mid-

1980s and experienced overfishing periodically from 1983 to 1997. 

However, after 2001, the models showed that the risk of overfishing was 

very low and that this population is probably still overfished but no 

longer experiencing overfishing (Jiao et al., 2011), likely a result of 

the implementation of stronger fishery management regulations since the 

early 1990s. Under the Magnuson-Stevens Fishery Conservation and 

Management Act (MSA), the term ``overfishing'' is defined as occurring 

when a stock experiences ``a level of fishing mortality that 

jeopardizes the capacity of a stock or stock complex to produce MSY 

[maximum sustainable yield] on a continuing basis'' (50 CFR 600.310). 

An ``overfished'' stock is defined as a stock whose biomass has 

declined below a level that jeopardizes the capacity of the stock to 

produce MSY on a continuing basis (50 CFR 600.310). However, it is 

important to note that these MSA classifications are based on different 

criteria (i.e., achieving MSY) than threatened or endangered statuses 

under the ESA. As such, ``overfished'' and ``overfishing'' 

classifications do not necessarily indicate that a species may warrant 

listing because they do not evaluate a species' extinction risk. 

However, they are relevant considerations for us to consider when we 

evaluate potential threats to the species from overutilization for 

commercial or recreational purposes.

    In Central America and the Caribbean, there are very little data on 

great hammerhead catches. The WEG petition references Denham et al. 

(2007) which states that hammerheads were heavily fished by longlines 

off the coast of Belize in the 1980s and early 1990s, leading to an 

observed decline in the abundance and size of hammerheads and prompting 

a halt in the Belize-based shark fishery. Fishing pressure on 

hammerheads still continues as a result of Guatemalan fishermen 

entering Belizean waters (Denham et al., 2007). However, catch records 

from the Cuban directed shark fishery show a small increase in the mean 

size of great hammerheads since 1992, suggesting partial recovery of 

the species in this region (Denham et al. 2007).

    The WEG petition also references a study (Feretti et al., 2008) 

that indicated that the population of smooth, scalloped, and great 

hammerheads in the Mediterranean Sea has experienced a greater than 99 

percent decline in abundance and biomass; however, the authors of this 

study note that only Sphyrna zygaena (smooth hammerhead) was assessed 

because the other hammerhead species occurred only sporadically in 

historical records. As such, this is not an appropriate index of the 

abundance of the other hammerhead species in the Mediterranean Sea and 

does not indicate overutilization of the great hammerhead shark in this 

region.

    In the Eastern Atlantic, off West Africa, the WEG petition states 

that the ``great hammerhead population is believed to have fallen 80 

percent as a result of unmanaged and unmonitored fisheries,'' but we 

could not verify the original source of this statistic. Data from the 

European pelagic freezer-trawler fishery that operates off Mauritania 

shows hammerhead species, including S. mokarran, constitute a 

significant component of the fishery's bycatch. Between 2001 and 2005, 

42 percent of the retained pelagic megafauna bycatch from over 1,400 

freezer-trawl sets consisted of hammerhead species, with around 75 

percent of the hammerhead catch juveniles of 0.50-1.40 m in length 

(Zeeberg et al., 2006). According to Denham et al. (2007), the sub-

regional plan of action for sharks of West Africa identified S. 

mokarran as particularly threatened in the region, with a noticeable 

decline in the population and collapse of landings. Citing unpublished 

data and anecdotal evidence, Denham et al. (2007) suggests that S. 

mokarran is ``almost extirpated'' from waters off Mauritania to Angola 

after previously being abundant in these areas in the early 1980s. The 

growth of fisheries targeting sharks in this region for the lucrative 

fin trade has likely contributed to the great hammerhead decline. By 

the 1980s, many fishers were specializing in catching sharks (Denham et 

al., 2007), with some artisanal fisheries in West Africa specifically 

specializing in catching sphyrnid species (CITES, 2010).

    In the Indian Ocean, pelagic sharks, including the great 

hammerhead, are targeted in various fisheries, including semi-

industrial, artisanal, and recreational fisheries. Countries that fish 

for sharks include: Egypt, India, Iran, Oman, Saudi Arabia, Sudan, 

United Arab Emirates, and Yemen, where the probable or actual status of 

shark populations is unknown, and Maldives, Kenya, Mauritius, 

Seychelles, South Africa, and United Republic of Tanzania, where the 

actual status of shark population is presumed to be fully to 

overexploited (de Young, 2006). Analysis of fishery-independent data 

from the KwaZulu-Natal beach protection program off South Africa 

revealed declines in the catch rates of S. mokarran since the late 

1970s. Specifically, from 1978-2003, annual catch per unit effort 

(CPUE; in number of sharks per km net year) of S. mokarran declined by 

79 percent, from 0.44 to 0.09 (Dudley and Simpfendorfer, 2006). The 

results were statistically significant, with the slope of the linear

 

[[Page 24705]]

 

regression = -0.014, and the majority of the catch (greater than 64 

percent) being immature great hammerhead sharks (Dudley and 

Simpfendorfer, 2006).

    In Australian waters, sharks are caught by commercial, recreational 

and traditional fishers as targeted catch, retained catch, and bycatch. 

Almost all sharks landed in Australia are used for domestic 

consumption. According to Bensley et al. (2010), the annual commercial 

Australian shark catch from 1996 to 2006 ranged from about 8,600 mt to 

11,500 mt; however, the reporting of catch weights varied due to the 

state of processing (e.g., whole weight, processed weight, landed 

weight, etc.). Data from protective shark meshing programs off beaches 

in New South Wales (NSW) and Queensland suggest declines in hammerhead 

populations off the east coast of Australia. Over a 35-year period, the 

number of hammerheads caught per year in NSW beach nets decreased by 

more than 90 percent, from over 300 individuals in 1973 to less than 30 

in 2008, although the majority of the hammerhead catch was likely S. 

zygaena (Williamson, 2011). Similarly, data from the Queensland shark 

control program indicate declines of around 79 percent in hammerhead 

shark abundance between 1986 and 2010 (although it was estimated that 

S. lewini made up the majority of this catch) (Queensland Department of 

Employment, Economic Development and Innovation (QLD DEEDI), 2011). S. 

mokarran abundance in the nets fluctuated over the years, but remained 

below 20 individuals per year, until 2008/2009 when a peak of 33 

individuals was caught in the net (QLD DEEDI, 2011). Abundance has 

since declined by around 48 percent to 17 individuals in 2011/2012 (QLD 

DEEDI, 2011). In Australia's northwest marine region, Heupel and 

McAuley (2007) analyzed CPUE data from the northern shark fisheries for 

the period of 1996-2005 and reported hammerhead abundance declines of 

58-76 percent.

    Given the value and contribution of great hammerhead fins in the 

international fin trade and the evidence of historical and current 

fishing pressure and subsequent population declines, we conclude that 

the information in the petitions and in our files suggests that global 

fisheries are impacting great hammerhead shark populations to a degree 

that raises concerns of a risk of extinction.

 

 Inadequacy of Existing Regulatory Mechanisms

 

    The petitions assert that the existing international and domestic 

management measures of several nations have failed to adequately 

protect the great hammerhead or stop ongoing population declines and 

present information on some of the current national and international 

shark regulations. Although the WEG petition mentions the International 

Convention for the Conservation of Atlantic Tunas (ICCAT) 

Recommendation 10-08, prohibiting the retention, transshipment, 

landing, storing, or offering for sale any part or carcass of 

hammerhead sharks of the family Sphyrnidae (except for bonnethead 

shark), the petition states that ``these are merely recommendations and 

do not do enough to bind the relevant actors.'' On the contrary, the 

``relevant actors,'' of which we assume the petitioner is referring to 

ICCAT Contracting Parties, are bound to implement management measures 

consistent with achieving ICCAT recommendations under Article VIII of 

the ICCAT Convention. On August 29, 2011, we finalized the 

implementation of Recommendation 10-08 through passage of a final rule 

that prohibits the retention, possession, transshipment, landing, 

storing, selling or purchasing of oceanic whitetip sharks or scalloped, 

smooth, or great hammerheads by U.S. commercial highly migratory 

species (HMS) pelagic longline fishery and recreational fisheries for 

tunas, swordfish, and billfish in the Atlantic Ocean, including the 

Caribbean Sea and Gulf of Mexico (76 FR 53652; August 29, 2011). 

However, the exemption available to developing coastal States in this 

ICCAT recommendation, which allows them to retain hammerhead sharks for 

local consumption as long as no hammerhead parts enter international 

trade, is troubling. As this exception provides a lesser degree of 

protection for hammerhead sharks in some developing coastal States, it 

may be a cause for concern for great hammerhead populations in the 

Atlantic Ocean.

    In addition, the petitions note that there is limited international 

management of the great hammerhead shark, which is generally allowed to 

be harvested outside of U.S. waters and ICCAT fisheries. The other 

regional fishery management organizations (RFMOs) do not have any 

species-specific regulations for great hammerhead sharks, but have 

addressed the controversial practice of shark finning (which involves 

harvesting sharks, severing their fins and returning their remaining 

carcasses to the sea) by adopting shark finning bans to reduce the 

number of sharks killed solely for their fins. However, as the WEG 

petition points out, these finning bans are enforced by monitoring the 

fin-to-carcass weight ratio, with this ratio set at 5 percent (i.e., 

onboard fins cannot weigh more than 5 percent of the weight of sharks 

onboard, up to the first point of landing). In a study that looked at 

species-specific shark-fin-to-body-mass ratios, the great hammerhead 

shark had an average wet-fin-to-round-mass ratio of 1.96 percent (Biery 

and Pauly, 2012), much lower than the designated 5 percent. These 

results suggest that fishers of great hammerhead sharks would be able 

to land more fins than bodies and still pass inspection, essentially 

allowing them to continue the wasteful practice of shark finning at sea 

in these RFMO convention areas.

    Domestic laws and regulations for other nations may also be lacking 

in certain areas of the great hammerhead range. For example, in Central 

America and the Caribbean, Kyne et al. (2012) notes that due in large 

part to the number of autonomous countries found in this region, the 

management of shark species remains largely disjointed, with some 

countries lacking basic fisheries regulations, and weak enforcement of 

those they do have. Off West Africa, weak fisheries management has led 

to many of their fish stocks being declared fully exploited to 

overexploited (FAO, 2012). Environmental Justice Foundation (EJF) 

(2012) notes that even countries with stricter fishing regulations in 

this region lack the resources to provide effective or, for that 

matter, any enforcement, with some countries lacking basic monitoring 

systems. In addition, reports of illegal, unregulated, and unreported 

fishing are prevalent in the waters off West Africa and account for 

around 37 percent of the region's catch, the highest regional estimate 

of illegal fishing worldwide (Agnew et al., 2009; EJF, 2012). Illegal 

fishing is also common in the western central Pacific and eastern 

Indian Ocean (Agnew et al., 2009), with many reports of vessels being 

caught with illegal shark carcasses and fins onboard (Paul, 2009). As 

the NRDC petition notes, ``as recently as 2011, illegal fishing and 

finning of hammerhead sharks was documented in the Galapagos Marine 

Reserve,'' suggesting that illegal shark fishing may still be an 

impediment to conservation despite increasing international efforts to 

protect sharks. Without stricter fishery regulations or enforcement, 

there is concern that captures of great hammerhead sharks, both legal 

and illegal, may be kept, especially considering the high price that 

great hammerhead fins fetch in the international fin trade market. The 

information in the petitions and in our

 

[[Page 24706]]

 

files suggests that while there is increasing support for national and 

international shark conservation and regulation, the existing 

regulatory mechanisms in some portions of the S. mokarran range may be 

inadequate to address threats to the global great hammerhead 

population.

 

Other Natural or Manmade Factors

 

    The WEG petition contends that ``biological vulnerability'' in the 

form of long gestation periods, late maturity, and large size makes 

great hammerheads especially susceptible to overutilization. The 

species has low productivity (intrinsic rate of population increase per 

year = 0.070; Cort[eacute]s et al., 2012), which makes it generally 

vulnerable to depletion and slow to recover from overexploitation. In 

addition, both petitions mention the great hammerhead sharks' high 

capture mortality rate on bottom longline (BLL) gear. This high at-

vessel mortality makes the shark vulnerable to fishing pressure, with 

any capture of this species, regardless of whether the fishing is 

targeted or incidental, contributing to its fishing mortality. In the 

northwest Atlantic, at-vessel fishing mortality on BLL gear (averaged 

for all age groups) was estimated to be 93.8 percent for great 

hammerhead sharks (Morgan and Burgess, 2007). However, in an ecological 

risk assessment of 20 shark stocks, Cortes et al. (2012) found that the 

great hammerhead ranked 14th in terms of its susceptibility to pelagic 

longline fisheries in the Atlantic Ocean. This information suggests 

that the species' biological vulnerability (low productivity and high 

at-vessel mortality) may be a threat in certain fisheries, possibly 

contributing to an increased risk of extinction, but may not be a cause 

for concern in other fisheries.

 

Conclusion

 

    We conclude that the information in the petition and in our files 

suggests that fisheries, inadequate existing regulatory mechanisms, and 

other natural factors may be impacting great hammerhead shark 

populations to a degree that raises concerns of a risk of extinction, 

with evidence of population depletions throughout the entire range of 

the great hammerhead shark. We find that the WEG petition's discussion 

of the present and threatened destruction, modification, and 

curtailment of the great hammerhead's habitat and range due to growing 

human populations and both petitions' discussions of climate change 

threats to habitats do not constitute substantial information 

indicating that listing may be warranted. The petitioners fail to show 

if the great hammerhead shark is responding in a negative fashion to 

those specific threats. For example, neither petition provides 

evidence, nor is there information in our files, to indicate that 

hypoxic occurrences and dead zones, a result of growing human 

populations, urban pollution, and climate warming, negatively impact 

shark populations. In fact, shark abundance can be very high in dead 

zones (Driggers and Hoffmayer, personal communication, 2013). In 

addition, both petitions assert that the loss of coral reef habitat due 

to climate change puts great hammerheads at risk of extinction; 

however, great hammerhead sharks are highly migratory species and are 

not limited to reef habitats. Additionally, another interpretation of 

the information could be that as ocean temperatures warm, more adequate 

habitat for great hammerheads would become available as they are a 

tropical species. The WEG petition also does not provide substantial 

information indicating that listing may be warranted due to the 

presence of mercury, PCBs, and arsenic in the great hammerhead shark's 

environment. The WEG petition references studies that examined the 

concentrations of these metals and organic compounds in different shark 

species, but it does not provide information, nor is there information 

in the references or in our files, on the effects of these substances 

and concentrations on great hammerhead sharks. In fact, the petition 

quotes a reference, stating that ``scientists found that `[a]ll life-

history stages [of the great white shark] may be vulnerable to high 

body burdens of anthropogenic toxins; how these may impact the 

population is not known.' '' In addition, one of the petition's 

references, Storelli et al. (2003), states ``[i]t is hypothesed [sic] 

that the large size of elasmobranch liver provides a greater ability to 

eliminate organic toxicants than in other fishes.'' The reference also 

mentions that in marine mammals selenium has a detoxifying effect 

against mercury intoxication when the molar ratio between the two 

metals is close to one, and observed similar ratios in shark liver 

``indicating that this particular mechanism may also be valid for 

sharks'' (Storelli et al., 2003). We conclude that given the 

information in the petition, references, and in our files, the petition 

fails to show that the great hammerhead may be responding in a negative 

fashion to these proposed threats.

 

Summary of ESA Section 4(a)(1) Factors

 

    We conclude that the petitions present substantial scientific or 

commercial information indicating that the petitioned action may be 

warranted due to a combination of the following three ESA section 

4(a)(1) factors that may be causing or contributing to an increased 

risk of extinction for the great hammerhead shark: Overutilization for 

commercial, recreational, scientific, or educational purposes, 

inadequate existing regulatory mechanisms, and other natural factors. 

However, we conclude that the WEG petition does not present substantial 

scientific or commercial information indicating that the petitioned 

action may be warranted based on the remaining two ESA section 4(a)(1) 

factors: The present or threatened destruction, modification, or 

curtailment of its habitat or range; or disease or predation.

 

Petition Finding

 

    After reviewing the information contained in the petitions, as well 

as information readily available in our files, and based on the above 

analysis, we conclude that the petitions present substantial scientific 

information indicating that the petitioned action of listing the great 

hammerhead shark range-wide as threatened or endangered may be 

warranted. Therefore, in accordance with section 4(b)(3)(B) of the ESA 

and NMFS' implementing regulations (50 CFR 424.14(b)(2)), we will 

commence a status review of the species. During our status review, we 

will first determine whether the species is in danger of extinction 

(endangered) or likely to become so (threatened) throughout all or a 

significant portion of its range. If it is not, then we will consider 

whether any populations meet the DPS policy criteria, and if so, 

whether any of these are threatened or endangered throughout all or a 

significant portion of their ranges. We now initiate this review, and 

thus, the great hammerhead shark is considered to be a candidate 

species (69 FR 19975; April 15, 2004). Within 12 months of the receipt 

of the petition (December 21, 2013), we will make a finding as to 

whether listing the species (or any identified DPSs) as endangered or 

threatened is warranted as required by section 4(b)(3)(B) of the ESA. 

If listing the species (or any identified DPSs) 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 on 

whether the great hammerhead shark is endangered or

 

[[Page 24707]]

 

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 great 

hammerhead shark bycatch and retention in industrial, commercial, 

artisanal, and recreational fisheries worldwide; (5) historical and 

current data on great hammerhead shark discards in global fisheries; 

(6) data on the trade of great hammerhead 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 their 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.

 

We, NMFS, announce a 90-day finding on two petitions to list 

the great hammerhead shark (Sphyrna mokarran) range-wide or, in the 

alternative, the Northwest Atlantic distinct population segment (DPS) 

or any other identified DPSs as threatened or endangered under the 

Endangered Species Act (ESA), and to designate critical habitat. 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.

 

DATES: Information and comments on the subject action must be received 

by June 25, 2013.

 

ADDRESSES: You may submit comments, information, or data on this 

document, identified by the code NOAA-NMFS-2013-0046, by any of the 

following methods:

     Electronic Submissions: Submit all electronic comments via 

the Federal eRulemaking Portal. Go to www.regulations.gov/#!docketDetail;D=NOAA-NMFS-2013-0046, click the ``Comment Now!'' icon, 

complete the required fields, and enter or attach your comments.

     Mail: Submit written comments to Office of Protected 

Resources, NMFS, 1315 East-West Highway, Silver Spring, MD 20910.

     Fax: 301-713-4060, Attn: Maggie Miller.

    Instructions: 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 by NMFS. All comments received are a part of the 

public record and will generally be posted for public viewing on 

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. NMFS 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: Maggie Miller, NMFS, Office of 

Protected Resources, (301) 427-8403.

 

SUPPLEMENTARY INFORMATION: 

 

Background

 

    On December 21, 2012, we received a petition from WildEarth 

Guardians (WEG) to list the great hammerhead shark (Sphyrna mokarran) 

as threatened or endangered under the ESA throughout its entire range, 

or, as an alternative, to list any identified DPSs as threatened or 

endangered. The petitioners also requested that critical habitat be 

designated for the great hammerhead under the ESA. On March 19, 2013, 

we received a petition from Natural Resources Defense Council (NRDC) to 

list the northwest Atlantic DPS of great hammerhead shark as 

threatened, or, as an alternative, to list the great hammerhead shark 

range-wide as threatened, and to designate critical habitat. The joint 

U.S. Fish and Wildlife Service (USFWS)/NMFS Endangered Species Act 

Petition Management Guidance (1996) states that if we receive two 

petitions for the same species, the requests only differ in the 

requested status of the species, and a 90-day finding has not yet been 

made on the earlier petition, then the later petition will be combined 

with the earlier petition and a combined 90-day finding will be 

prepared. Since the initial petition requested listing of the species 

as threatened or endangered and the second petition only requested a 

threatened listing, and a finding has not been made on the initial 

petition, we have combined the WEG and NRDC petitions and this 90-day 

finding will address both. 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 that 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

 

[[Page 24702]]

 

conduct a comprehensive review of the best available scientific and 

commercial information. In such cases, we conclude the review with a 

finding as to whether, in fact, 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 more thorough review of the available 

information, as compared to the narrow scope of review at the 90-day 

stage, a finding that the ``petition presents substantial scientific or 

commercial information that the action may be warranted'' at this point 

does not predetermine 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-USFWS (jointly, ``the Services'') policy (DPS 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 

(ESA sections 3(6) and 3(20), respectively, 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 five section 4(a)(1) factors: (1) The 

present or threatened destruction, modification, or curtailment of 

habitat or range; (2) overutilization for commercial, recreational, 

scientific, or educational purposes; (3) disease or predation; (4) 

inadequacy of existing regulatory mechanisms; and (5) 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 the Services (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. 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 petition presents substantial 

information indicating the 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 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 it supports the 

petitioners' assertions. In other words, conclusive information 

indicating that 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 that 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 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

 

[[Page 24703]]

 

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 Hammerhead Shark

 

    The great hammerhead shark is a circumtropical species that lives 

in coastal-pelagic and semi-oceanic waters from latitudes of 40[deg] N 

to 35[deg] S (Compagno, 1984; Denham et al., 2007). It occurs over 

continental shelves as well as adjacent deep waters, and may also be 

found in coral reefs and lagoons (Compagno, 1984; Denham et al., 2007; 

Bester, n.d.). Great hammerhead sharks are highly mobile and seasonally 

migratory (Compagno, 1984; Denham et al., 2007; Hammerschlag et al., 

2011; Bester, n.d.). In the western Atlantic Ocean, the great 

hammerhead range extends from Massachusetts (although the species is 

rare north of North Carolina), in the United States, to Uruguay, 

including the Gulf of Mexico and Caribbean Sea. In the eastern 

Atlantic, it can be found from Morocco to Senegal, including in the 

Mediterranean Sea. The great hammerhead shark can also be found 

throughout the Indian Ocean and the Red Sea and in the Indo-Pacific 

region from Ryukyu Island south to New Caledonia and east to French 

Polynesia (Bester, n.d.). Distribution in the eastern Pacific Ocean 

extends from southern Baja California, including the Gulf of 

California, to Peru (Compagno, 1984).

    The general life history pattern of the great hammerhead shark is 

that of a long lived (oldest observed maximum age = 44 years; Piercy et 

al., 2010), large, and relatively slow growing species. The great 

hammerhead shark has a laterally expanded head that resembles a hammer, 

hence the common name ``hammerhead,'' and belongs to the Sphyrnidae 

family. The great hammerhead shark is the largest of the hammerheads, 

characterized by a nearly straight anterior margin of the head and 

median indentation in the center in adults, strongly serrated teeth, 

strongly falcate first dorsal and pelvic fins, and a high second dorsal 

fin with a concave rear margin (Compagno, 1984; Bester, n.d.). The body 

of the great hammerhead is fusiform, with the dorsal side colored dark 

brown to light grey or olive that shades to white on the ventral side 

(Compagno, 1984; Bester, n.d.). Fins of adult great hammerheads are 

uniform in color, while the tip of the second dorsal fin of juveniles 

may appear dusky (Bester, n.d.).

    The oldest aged great hammerhead sharks had lengths of 398 cm total 

length (TL) (female--44 years) and 379 cm TL (male--42 years) (Piercy 

et al., 2010), but they can reach lengths of over 610 cm TL (Compagno, 

1984). However, individuals greater than 400 cm TL are rare (Compagno, 

1984; Stevens and Lyle 1989), which Piercy et al. (2010) suggest may be 

attributed to growth overfishing. Estimates for size at maturity range 

from 234 to 269 cm TL for males and 210 to 300 cm TL for females 

(Compagno, 1984; Stevens and Lyle 1989). Male great hammerhead sharks 

have also been shown to grow faster than females (with a growth 

coefficient, k, of 0.16/year for males and 0.11/year for females) but 

reach a smaller asymptotic size (335 cm TL for males versus 389 cm TL 

for females) (Piercy et al., 2010).

    The great hammerhead shark is viviparous (i.e., give birth to live 

young), with a gestation period of 10-11 months, and likely breeds 

every other year (Stevens and Lyle, 1989). Litter sizes range from 6 to 

42 live pups (Compagno, 1984; Stevens and Lyle, 1989). Length at birth 

estimates for great hammerheads range from 50-70 cm TL (Compagno, 1984; 

Stevens and Lyle, 1989).

    The great hammerhead shark is a high trophic level predator 

(Cort[eacute]s, 1999) and opportunistic feeder, with a diet that 

includes a wide variety of teleosts, cephalopods, and crustaceans, with 

a preference for stingrays (Compagno, 1984; Denham et al., 2007).

 

Analysis of Petition and Information Readily Available in NMFS Files

 

    We evaluated the information provided in the petition and readily 

available in our files to determine if the petitions presented 

substantial scientific or commercial information indicating that the 

petitioned actions may be warranted. The petitions contain information 

on the species, including the taxonomy, species description, geographic 

distribution, and habitat, with some information on population status 

and trends in certain locations, and factors contributing to the 

species' decline. The petitions state that commercial fishing, both 

targeted and bycatch, is the primary threat to the great hammerhead 

shark. The petitioners also assert that current habitat destruction, 

deposition of pollutants, lack of adequate regulatory mechanisms 

nationally and worldwide, global climate warming, as well the species' 

biological constraints, increase the susceptibility of the great 

hammerhead shark to extinction.

    According to the WEG petition, all five causal factors in section 

4(a)(1) of the ESA are adversely affecting the continued existence of 

the great hammerhead shark: (A) The present or threatened destruction, 

modification, or curtailment of its habitat or range; (B) 

overutilization for commercial, recreational, scientific, or 

educational purposes; (C) disease or predation; (D) inadequacy of 

existing regulatory mechanisms; and (E) other natural or manmade 

factors affecting its continued existence. The focus of the NRDC 

petition is mainly on the northwest Atlantic population and it 

identified the threats of: (B) overutilization for commercial, 

recreational, scientific, or educational purposes; (D) inadequacy of 

existing regulatory mechanisms; and (E) other natural or manmade 

factors affecting its continued existence. In the following sections, 

we use the information presented in the petition and in our files to 

determine whether the petitioned action may be warranted. If requested 

to list a global population and, alternatively, a DPS, we first 

determine if the petition presents substantial information that the 

petitioned action is warranted for the global population. If it does, 

then we make a positive finding on the petition and will revisit the 

question of DPSs during a status review, if necessary. If the petition 

does not present substantial information that the global population may 

warrant listing, and it has requested that we list any populations of 

the species as threatened or endangered, then we consider whether the 

petition provides substantial information that the requested 

population(s) may qualify as DPSs under the discreteness and 

significance criteria of our joint DPS Policy, and if listing any of 

those DPSs may be warranted. We summarize our analysis and conclusions 

regarding the information presented by the petitioners and in our files 

on the specific ESA section 4(a)(1) factors that we find may be 

affecting the species' risk of global extinction below.

 

Overutilization for Commercial, Recreational, Scientific, or 

Educational Purposes

 

    Information from the petitions and in our files suggests that the 

primary threat to the great hammerhead shark is from fisheries. Great 

hammerhead sharks are both targeted and taken as bycatch in many global 

fisheries (e.g., bottom and pelagic longlines, coastal gillnet 

fisheries, artisanal fisheries). Because of their large fins with high 

fin needle

 

[[Page 24704]]

 

content (a gelatinous product used to make shark fin soup), hammerheads 

fetch a high commercial value in the Asian shark fin trade (Abercrombie 

et al., 2005). However, the WEG petition overstates the contribution of 

great hammerheads in the Hong Kong fin trade market by presenting 

information on the trade of scalloped, smooth, and great hammerhead 

fins together. According to a genetic study that examined the 

concordance between assigned Hong Kong market categories and the 

corresponding fins, the great hammerhead market category ``Gu pian'' 

had an 88 percent concordance rate, indicating that traders are able to 

accurately identify and separate great hammerhead fins from the other 

hammerhead species (Abercrombie et al., 2005; Clarke et al., 2006a). As 

such, here we provide the information on a finer scale level (down to 

the species level) to evaluate the extent that the fin trade may 

contribute to the overutilization of the great hammerhead shark. 

According to Clarke et al. (2006a), S. mokarran is estimated to 

comprise approximately 1.5 percent of the total fins traded annually in 

the Hong Kong fin market. As mentioned above, great hammerhead fins are 

primarily traded under the ``Gu pian'' market category, where the 

market value for the average, wholesale, unprocessed fin is around 

$135/kg, the most for any of the hammerhead fins (Abercrombie et al., 

2005). Extrapolating the fin data to numbers of sharks, Clarke et al. 

(2006b) estimates that around 375,000 (95 percent confidence interval = 

130,000-1.1 million) individuals of this species (equivalent to a 

biomass of around 21,000 metric tons, (mt)) are traded annually in the 

Hong Kong fin market. Given their high price in the Hong Kong market, 

there is concern that many great hammerheads caught as incidental catch 

may be kept for the fin trade as opposed to released alive.

    In the United States, great hammerhead sharks are mainly caught as 

bycatch in commercial longline and net fisheries and by recreational 

fishers using rod and reel. A recent stock assessment by Jiao et al. 

(2011) used a Bayesian hierarchical approach to assess the data-poor 

hammerhead species and found that the northwestern Atlantic and Gulf of 

Mexico great hammerhead population likely became overfished in the mid-

1980s and experienced overfishing periodically from 1983 to 1997. 

However, after 2001, the models showed that the risk of overfishing was 

very low and that this population is probably still overfished but no 

longer experiencing overfishing (Jiao et al., 2011), likely a result of 

the implementation of stronger fishery management regulations since the 

early 1990s. Under the Magnuson-Stevens Fishery Conservation and 

Management Act (MSA), the term ``overfishing'' is defined as occurring 

when a stock experiences ``a level of fishing mortality that 

jeopardizes the capacity of a stock or stock complex to produce MSY 

[maximum sustainable yield] on a continuing basis'' (50 CFR 600.310). 

An ``overfished'' stock is defined as a stock whose biomass has 

declined below a level that jeopardizes the capacity of the stock to 

produce MSY on a continuing basis (50 CFR 600.310). However, it is 

important to note that these MSA classifications are based on different 

criteria (i.e., achieving MSY) than threatened or endangered statuses 

under the ESA. As such, ``overfished'' and ``overfishing'' 

classifications do not necessarily indicate that a species may warrant 

listing because they do not evaluate a species' extinction risk. 

However, they are relevant considerations for us to consider when we 

evaluate potential threats to the species from overutilization for 

commercial or recreational purposes.

    In Central America and the Caribbean, there are very little data on 

great hammerhead catches. The WEG petition references Denham et al. 

(2007) which states that hammerheads were heavily fished by longlines 

off the coast of Belize in the 1980s and early 1990s, leading to an 

observed decline in the abundance and size of hammerheads and prompting 

a halt in the Belize-based shark fishery. Fishing pressure on 

hammerheads still continues as a result of Guatemalan fishermen 

entering Belizean waters (Denham et al., 2007). However, catch records 

from the Cuban directed shark fishery show a small increase in the mean 

size of great hammerheads since 1992, suggesting partial recovery of 

the species in this region (Denham et al. 2007).

    The WEG petition also references a study (Feretti et al., 2008) 

that indicated that the population of smooth, scalloped, and great 

hammerheads in the Mediterranean Sea has experienced a greater than 99 

percent decline in abundance and biomass; however, the authors of this 

study note that only Sphyrna zygaena (smooth hammerhead) was assessed 

because the other hammerhead species occurred only sporadically in 

historical records. As such, this is not an appropriate index of the 

abundance of the other hammerhead species in the Mediterranean Sea and 

does not indicate overutilization of the great hammerhead shark in this 

region.

    In the Eastern Atlantic, off West Africa, the WEG petition states 

that the ``great hammerhead population is believed to have fallen 80 

percent as a result of unmanaged and unmonitored fisheries,'' but we 

could not verify the original source of this statistic. Data from the 

European pelagic freezer-trawler fishery that operates off Mauritania 

shows hammerhead species, including S. mokarran, constitute a 

significant component of the fishery's bycatch. Between 2001 and 2005, 

42 percent of the retained pelagic megafauna bycatch from over 1,400 

freezer-trawl sets consisted of hammerhead species, with around 75 

percent of the hammerhead catch juveniles of 0.50-1.40 m in length 

(Zeeberg et al., 2006). According to Denham et al. (2007), the sub-

regional plan of action for sharks of West Africa identified S. 

mokarran as particularly threatened in the region, with a noticeable 

decline in the population and collapse of landings. Citing unpublished 

data and anecdotal evidence, Denham et al. (2007) suggests that S. 

mokarran is ``almost extirpated'' from waters off Mauritania to Angola 

after previously being abundant in these areas in the early 1980s. The 

growth of fisheries targeting sharks in this region for the lucrative 

fin trade has likely contributed to the great hammerhead decline. By 

the 1980s, many fishers were specializing in catching sharks (Denham et 

al., 2007), with some artisanal fisheries in West Africa specifically 

specializing in catching sphyrnid species (CITES, 2010).

    In the Indian Ocean, pelagic sharks, including the great 

hammerhead, are targeted in various fisheries, including semi-

industrial, artisanal, and recreational fisheries. Countries that fish 

for sharks include: Egypt, India, Iran, Oman, Saudi Arabia, Sudan, 

United Arab Emirates, and Yemen, where the probable or actual status of 

shark populations is unknown, and Maldives, Kenya, Mauritius, 

Seychelles, South Africa, and United Republic of Tanzania, where the 

actual status of shark population is presumed to be fully to 

overexploited (de Young, 2006). Analysis of fishery-independent data 

from the KwaZulu-Natal beach protection program off South Africa 

revealed declines in the catch rates of S. mokarran since the late 

1970s. Specifically, from 1978-2003, annual catch per unit effort 

(CPUE; in number of sharks per km net year) of S. mokarran declined by 

79 percent, from 0.44 to 0.09 (Dudley and Simpfendorfer, 2006). The 

results were statistically significant, with the slope of the linear

 

[[Page 24705]]

 

regression = -0.014, and the majority of the catch (greater than 64 

percent) being immature great hammerhead sharks (Dudley and 

Simpfendorfer, 2006).

    In Australian waters, sharks are caught by commercial, recreational 

and traditional fishers as targeted catch, retained catch, and bycatch. 

Almost all sharks landed in Australia are used for domestic 

consumption. According to Bensley et al. (2010), the annual commercial 

Australian shark catch from 1996 to 2006 ranged from about 8,600 mt to 

11,500 mt; however, the reporting of catch weights varied due to the 

state of processing (e.g., whole weight, processed weight, landed 

weight, etc.). Data from protective shark meshing programs off beaches 

in New South Wales (NSW) and Queensland suggest declines in hammerhead 

populations off the east coast of Australia. Over a 35-year period, the 

number of hammerheads caught per year in NSW beach nets decreased by 

more than 90 percent, from over 300 individuals in 1973 to less than 30 

in 2008, although the majority of the hammerhead catch was likely S. 

zygaena (Williamson, 2011). Similarly, data from the Queensland shark 

control program indicate declines of around 79 percent in hammerhead 

shark abundance between 1986 and 2010 (although it was estimated that 

S. lewini made up the majority of this catch) (Queensland Department of 

Employment, Economic Development and Innovation (QLD DEEDI), 2011). S. 

mokarran abundance in the nets fluctuated over the years, but remained 

below 20 individuals per year, until 2008/2009 when a peak of 33 

individuals was caught in the net (QLD DEEDI, 2011). Abundance has 

since declined by around 48 percent to 17 individuals in 2011/2012 (QLD 

DEEDI, 2011). In Australia's northwest marine region, Heupel and 

McAuley (2007) analyzed CPUE data from the northern shark fisheries for 

the period of 1996-2005 and reported hammerhead abundance declines of 

58-76 percent.

    Given the value and contribution of great hammerhead fins in the 

international fin trade and the evidence of historical and current 

fishing pressure and subsequent population declines, we conclude that 

the information in the petitions and in our files suggests that global 

fisheries are impacting great hammerhead shark populations to a degree 

that raises concerns of a risk of extinction.

 

 Inadequacy of Existing Regulatory Mechanisms

 

    The petitions assert that the existing international and domestic 

management measures of several nations have failed to adequately 

protect the great hammerhead or stop ongoing population declines and 

present information on some of the current national and international 

shark regulations. Although the WEG petition mentions the International 

Convention for the Conservation of Atlantic Tunas (ICCAT) 

Recommendation 10-08, prohibiting the retention, transshipment, 

landing, storing, or offering for sale any part or carcass of 

hammerhead sharks of the family Sphyrnidae (except for bonnethead 

shark), the petition states that ``these are merely recommendations and 

do not do enough to bind the relevant actors.'' On the contrary, the 

``relevant actors,'' of which we assume the petitioner is referring to 

ICCAT Contracting Parties, are bound to implement management measures 

consistent with achieving ICCAT recommendations under Article VIII of 

the ICCAT Convention. On August 29, 2011, we finalized the 

implementation of Recommendation 10-08 through passage of a final rule 

that prohibits the retention, possession, transshipment, landing, 

storing, selling or purchasing of oceanic whitetip sharks or scalloped, 

smooth, or great hammerheads by U.S. commercial highly migratory 

species (HMS) pelagic longline fishery and recreational fisheries for 

tunas, swordfish, and billfish in the Atlantic Ocean, including the 

Caribbean Sea and Gulf of Mexico (76 FR 53652; August 29, 2011). 

However, the exemption available to developing coastal States in this 

ICCAT recommendation, which allows them to retain hammerhead sharks for 

local consumption as long as no hammerhead parts enter international 

trade, is troubling. As this exception provides a lesser degree of 

protection for hammerhead sharks in some developing coastal States, it 

may be a cause for concern for great hammerhead populations in the 

Atlantic Ocean.

    In addition, the petitions note that there is limited international 

management of the great hammerhead shark, which is generally allowed to 

be harvested outside of U.S. waters and ICCAT fisheries. The other 

regional fishery management organizations (RFMOs) do not have any 

species-specific regulations for great hammerhead sharks, but have 

addressed the controversial practice of shark finning (which involves 

harvesting sharks, severing their fins and returning their remaining 

carcasses to the sea) by adopting shark finning bans to reduce the 

number of sharks killed solely for their fins. However, as the WEG 

petition points out, these finning bans are enforced by monitoring the 

fin-to-carcass weight ratio, with this ratio set at 5 percent (i.e., 

onboard fins cannot weigh more than 5 percent of the weight of sharks 

onboard, up to the first point of landing). In a study that looked at 

species-specific shark-fin-to-body-mass ratios, the great hammerhead 

shark had an average wet-fin-to-round-mass ratio of 1.96 percent (Biery 

and Pauly, 2012), much lower than the designated 5 percent. These 

results suggest that fishers of great hammerhead sharks would be able 

to land more fins than bodies and still pass inspection, essentially 

allowing them to continue the wasteful practice of shark finning at sea 

in these RFMO convention areas.

    Domestic laws and regulations for other nations may also be lacking 

in certain areas of the great hammerhead range. For example, in Central 

America and the Caribbean, Kyne et al. (2012) notes that due in large 

part to the number of autonomous countries found in this region, the 

management of shark species remains largely disjointed, with some 

countries lacking basic fisheries regulations, and weak enforcement of 

those they do have. Off West Africa, weak fisheries management has led 

to many of their fish stocks being declared fully exploited to 

overexploited (FAO, 2012). Environmental Justice Foundation (EJF) 

(2012) notes that even countries with stricter fishing regulations in 

this region lack the resources to provide effective or, for that 

matter, any enforcement, with some countries lacking basic monitoring 

systems. In addition, reports of illegal, unregulated, and unreported 

fishing are prevalent in the waters off West Africa and account for 

around 37 percent of the region's catch, the highest regional estimate 

of illegal fishing worldwide (Agnew et al., 2009; EJF, 2012). Illegal 

fishing is also common in the western central Pacific and eastern 

Indian Ocean (Agnew et al., 2009), with many reports of vessels being 

caught with illegal shark carcasses and fins onboard (Paul, 2009). As 

the NRDC petition notes, ``as recently as 2011, illegal fishing and 

finning of hammerhead sharks was documented in the Galapagos Marine 

Reserve,'' suggesting that illegal shark fishing may still be an 

impediment to conservation despite increasing international efforts to 

protect sharks. Without stricter fishery regulations or enforcement, 

there is concern that captures of great hammerhead sharks, both legal 

and illegal, may be kept, especially considering the high price that 

great hammerhead fins fetch in the international fin trade market. The 

information in the petitions and in our

 

[[Page 24706]]

 

files suggests that while there is increasing support for national and 

international shark conservation and regulation, the existing 

regulatory mechanisms in some portions of the S. mokarran range may be 

inadequate to address threats to the global great hammerhead 

population.

 

Other Natural or Manmade Factors

 

    The WEG petition contends that ``biological vulnerability'' in the 

form of long gestation periods, late maturity, and large size makes 

great hammerheads especially susceptible to overutilization. The 

species has low productivity (intrinsic rate of population increase per 

year = 0.070; Cort[eacute]s et al., 2012), which makes it generally 

vulnerable to depletion and slow to recover from overexploitation. In 

addition, both petitions mention the great hammerhead sharks' high 

capture mortality rate on bottom longline (BLL) gear. This high at-

vessel mortality makes the shark vulnerable to fishing pressure, with 

any capture of this species, regardless of whether the fishing is 

targeted or incidental, contributing to its fishing mortality. In the 

northwest Atlantic, at-vessel fishing mortality on BLL gear (averaged 

for all age groups) was estimated to be 93.8 percent for great 

hammerhead sharks (Morgan and Burgess, 2007). However, in an ecological 

risk assessment of 20 shark stocks, Cortes et al. (2012) found that the 

great hammerhead ranked 14th in terms of its susceptibility to pelagic 

longline fisheries in the Atlantic Ocean. This information suggests 

that the species' biological vulnerability (low productivity and high 

at-vessel mortality) may be a threat in certain fisheries, possibly 

contributing to an increased risk of extinction, but may not be a cause 

for concern in other fisheries.

 

Conclusion

 

    We conclude that the information in the petition and in our files 

suggests that fisheries, inadequate existing regulatory mechanisms, and 

other natural factors may be impacting great hammerhead shark 

populations to a degree that raises concerns of a risk of extinction, 

with evidence of population depletions throughout the entire range of 

the great hammerhead shark. We find that the WEG petition's discussion 

of the present and threatened destruction, modification, and 

curtailment of the great hammerhead's habitat and range due to growing 

human populations and both petitions' discussions of climate change 

threats to habitats do not constitute substantial information 

indicating that listing may be warranted. The petitioners fail to show 

if the great hammerhead shark is responding in a negative fashion to 

those specific threats. For example, neither petition provides 

evidence, nor is there information in our files, to indicate that 

hypoxic occurrences and dead zones, a result of growing human 

populations, urban pollution, and climate warming, negatively impact 

shark populations. In fact, shark abundance can be very high in dead 

zones (Driggers and Hoffmayer, personal communication, 2013). In 

addition, both petitions assert that the loss of coral reef habitat due 

to climate change puts great hammerheads at risk of extinction; 

however, great hammerhead sharks are highly migratory species and are 

not limited to reef habitats. Additionally, another interpretation of 

the information could be that as ocean temperatures warm, more adequate 

habitat for great hammerheads would become available as they are a 

tropical species. The WEG petition also does not provide substantial 

information indicating that listing may be warranted due to the 

presence of mercury, PCBs, and arsenic in the great hammerhead shark's 

environment. The WEG petition references studies that examined the 

concentrations of these metals and organic compounds in different shark 

species, but it does not provide information, nor is there information 

in the references or in our files, on the effects of these substances 

and concentrations on great hammerhead sharks. In fact, the petition 

quotes a reference, stating that ``scientists found that `[a]ll life-

history stages [of the great white shark] may be vulnerable to high 

body burdens of anthropogenic toxins; how these may impact the 

population is not known.' '' In addition, one of the petition's 

references, Storelli et al. (2003), states ``[i]t is hypothesed [sic] 

that the large size of elasmobranch liver provides a greater ability to 

eliminate organic toxicants than in other fishes.'' The reference also 

mentions that in marine mammals selenium has a detoxifying effect 

against mercury intoxication when the molar ratio between the two 

metals is close to one, and observed similar ratios in shark liver 

``indicating that this particular mechanism may also be valid for 

sharks'' (Storelli et al., 2003). We conclude that given the 

information in the petition, references, and in our files, the petition 

fails to show that the great hammerhead may be responding in a negative 

fashion to these proposed threats.

 

Summary of ESA Section 4(a)(1) Factors

 

    We conclude that the petitions present substantial scientific or 

commercial information indicating that the petitioned action may be 

warranted due to a combination of the following three ESA section 

4(a)(1) factors that may be causing or contributing to an increased 

risk of extinction for the great hammerhead shark: Overutilization for 

commercial, recreational, scientific, or educational purposes, 

inadequate existing regulatory mechanisms, and other natural factors. 

However, we conclude that the WEG petition does not present substantial 

scientific or commercial information indicating that the petitioned 

action may be warranted based on the remaining two ESA section 4(a)(1) 

factors: The present or threatened destruction, modification, or 

curtailment of its habitat or range; or disease or predation.

 

Petition Finding

 

    After reviewing the information contained in the petitions, as well 

as information readily available in our files, and based on the above 

analysis, we conclude that the petitions present substantial scientific 

information indicating that the petitioned action of listing the great 

hammerhead shark range-wide as threatened or endangered may be 

warranted. Therefore, in accordance with section 4(b)(3)(B) of the ESA 

and NMFS' implementing regulations (50 CFR 424.14(b)(2)), we will 

commence a status review of the species. During our status review, we 

will first determine whether the species is in danger of extinction 

(endangered) or likely to become so (threatened) throughout all or a 

significant portion of its range. If it is not, then we will consider 

whether any populations meet the DPS policy criteria, and if so, 

whether any of these are threatened or endangered throughout all or a 

significant portion of their ranges. We now initiate this review, and 

thus, the great hammerhead shark is considered to be a candidate 

species (69 FR 19975; April 15, 2004). Within 12 months of the receipt 

of the petition (December 21, 2013), we will make a finding as to 

whether listing the species (or any identified DPSs) as endangered or 

threatened is warranted as required by section 4(b)(3)(B) of the ESA. 

If listing the species (or any identified DPSs) 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 on 

whether the great hammerhead shark is endangered or

 

[[Page 24707]]

 

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 great 

hammerhead shark bycatch and retention in industrial, commercial, 

artisanal, and recreational fisheries worldwide; (5) historical and 

current data on great hammerhead shark discards in global fisheries; 

(6) data on the trade of great hammerhead 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 their 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.

 

 

 

 

 

 

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