2015 Shark Finning

Report to Congress
 

 


 


 


 


 

2015 Shark Finning Report to Congress 

Pursuant to the 

Shark Finning Prohibition Act 

(Public Law 106-557) 

U.S. Department of Commerce
 

National Oceanic and Atmospheric Administration
 

Prepared by the
 

National Marine Fisheries Service
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 

Introduction 

This report describes the efforts of the National Oceanic and Atmospheric Administration’s 

(NOAA) National Marine Fisheries Service (NMFS) during calendar year 2014 to implement the 

Shark Finning Prohibition Act and more recent shark conservation legislation. The 2000 Shark 

Finning Prohibition Act amended the Magnuson-Stevens Fishery Conservation and Management 

Act (MSA) to prohibit the practice of shark finning by any person under U.S. jurisdiction. 

The 2000 Shark Finning Prohibition Act requires NMFS to promulgate regulations to implement 

its provisions, initiate discussion with other nations to develop international agreements on shark 

finning and data collection, provide Congress with annual reports describing efforts to carry out 

the Shark Finning Prohibition Act, and establish research programs. 

Background 

The practice of shark finning and shark bycatch in some fisheries can affect the status of shark 

stocks and the sustainability of their exploitation in world fisheries. By 2000, global shark 

catches reported to the Food and Agriculture Organization of the United Nations (FAO) had 

tripled since 1950, reaching an all-time high of 888,000 tons. Since then, there has been about a 

15 percent decrease in catches, to 765,000 tons in 2012. However, research suggests the actual 

number of sharks landed internationally each year is underestimated (Clarke et al. 2006 ). For 

2013, global imports of shark fins were approximately 27,000 metric tons (mt), the largest 

volume since 2009. In 2013, the average value of shark fin imports decreased to $7,230/mt, 

while the average value of exports decreased to $12,637/mt. Malaysia was the largest importer 

and Thailand the largest exporter of shark fins for 2013. In response to concerns about growing 

shark harvests internationally, many countries have banned shark fishing in their waters in favor 

of promoting tourism opportunities. In addition, many other nations have adopted finning bans, 

including: Bahamas, Belize, Costa Rica, Dominican Republic, El Salvador, Guatemala, 

Honduras, Maldives, Nicaragua, Palau, Panama, and Taiwan. 

The MSA, as amended by the Shark Finning Prohibition Act and the Shark Conservation Act, is 

the Federal law governing the conservation and management of Federal fisheries in the United 

States. The suite of conservation and management measures required of all Federal fisheries 

under the MSA makes the United States a leader in the sustainable management of domestic 

shark fisheries. In 2014, three out of 34 U.S. shark stocks or stock complexes (8 percent) were 

listed as subject to overfishing, and five shark stocks (15 percent) were listed as overfished. 

Fifteen stocks or stock complexes (45 percent) had an unknown overfishing status, and 17 shark 

stocks or stock complexes (50 percent) had an unknown overfished status (Table 1). 

In the United States, shark finning has been prohibited since 2000. In 2011, President Obama 

signed the Shark Conservation Act of 2010, which amended the High Seas Driftnet Fishing 

Moratorium Protection Act and the 2000 Shark Finning Prohibition Act provisions of the MSA 

1 Clarke, S., M.K. McAllister, E.J. Milner-Gulland, G.P. Kirkwood, C.G.J. Michielsens, D.J. Agnew, E.K. Pikitch, 

H. Nakano, and M.S. Shivji. 2006. Global estimates of shark catches using trade records from commercial markets. 

Ecology Letters 10:1115–1126. 

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to further improve domestic and international shark conservation measures, including even 

stronger prohibitions against shark finning. In addition, many U.S. States and territories have 

passed laws addressing the possession, sale, trade, or distribution of shark fins, including Hawaii 

(2010), California (2011), Oregon (2011), Washington (2011), the Commonwealth of the 

Northern Mariana Islands (2011), Guam (2011), American Samoa (2012), Illinois (2012), 

Maryland (2013), Delaware (2013), New York (2013), and Massachusetts (2014). 

Domestically, the Shark Conservation Act states that it is illegal “to remove any of the fins of a 

shark (including the tail) at sea; to have custody, control, or possession of any such fin aboard a 

fishing vessel unless it is naturally attached to the corresponding carcass; to transfer any such fin 

from one vessel to another vessel at sea, or to receive any such fin in such transfer, without the 

fin naturally attached to the corresponding carcass; or to land any such fin that is not naturally 

attached to the corresponding carcass, or to land any shark carcass without such fins naturally 

attached.” These provisions improved the United States’ ability to enforce shark finning 

prohibitions in domestic shark fisheries. The 2010 Act also created an exemption for smooth 

dogfish (Mutelis canis) in the Atlantic “if the individual holds a valid State commercial fishing 

license, unless the total weight of smooth dogfish fins landed or found on board a vessel to which 

this subsection applies exceeds 12 percent of the total weight of smooth dogfish carcasses landed 

or found on board.” 

The Shark Conservation Act amended the High Seas Driftnet Fishing Moratorium Protection Act 

in two important ways. First, it requires the Secretary of Commerce to identify a nation if two or 

more fishing vessels of that nation have been engaged in fishing activities or practices in 

international waters that target or incidentally catch sharks and if that nation has not adopted a 

regulatory program to provide for the conservation of sharks, including measures to prohibit 

removal of shark fins at sea. Second, it directs the United States to urge international fishery 

management organizations to which the United States is a member to adopt shark conservation 

measures, such as prohibiting removal of shark fins at sea. It also directs the United States to 

enter into international agreements that require measures for the conservation of sharks. These 

approaches, along with our strong domestic shark fishery management, have made the United 

States a leader in the conservation and management of sharks globally. 

Table 1 

Status of Shark Stocks and Stock Complexes 

in U.S. Fisheries in 2014 

Fishery 

Management 

Council (FMC) 

Fishery Management 

Plan (FMP) or 

Fishery Ecosystem 

Plan (FEP) 

Stock or Stock Complex Overfishing Overfished 

New England 

FMC & MidAtlantic FMC Spiny Dogfish FMP Spiny dogfish – Atlantic coast No No 

NMFS Highly 

Migratory 

Species 

Division 

Consolidated Atlantic 

Highly Migratory 

Species FMP 

Atlantic large coastal shark complex* Unknown Unknown 

Atlantic pelagic shark complex** Unknown Unknown 

Atlantic sharpnose shark-Atlantic No No 

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Atlantic sharpnose shark- Gulf of 

Mexico No No 

Blacknose shark – Atlantic Yes Yes 

Blacknose shark – Gulf of Mexico Unknown Unknown 

Blacktip shark – Gulf of Mexico No No 

Blacktip shark –Atlantic Unknown Unknown 

Blue shark – Atlantic and Gulf of 

Mexico No No 

Bonnethead – Atlantic Unknown Unknown 

Dusky shark – Atlantic and Gulf of 

Mexico Yes Yes 

Finetooth shark – Atlantic and Gulf 

of Mexico No No 

Porbeagle – Atlantic and Gulf of 

Mexico No Yes 

Sandbar shark – Atlantic and Gulf of 

Mexico No Yes 

Scalloped hammerhead shark – 

Atlantic and Gulf of Mexico Yes Yes 

Shortfin mako – Atlantic No No 

Pacific FMC Pacific Coast Groundfish 

FMP 

Leopard shark – Pacific Coast No No 

Spiny dogfish – Pacific Coast No No 

Soupfin (Tope) – Pacific Coast No No 

Pacific FMC & 

Western 

Pacific FMC 

U.S. West Coast 

Fisheries for Highly 

Migratory Species & 

Pacific Pelagic FEP 

Thresher shark – North Pacific No No 

Shortfin mako shark – North Pacific Unknown Unknown 

Blue shark – North Pacific No No 

Western 

Pacific FMC 

FEP for Pelagic 

Fisheries of the Western 

Pacific Region (Pacific 

Pelagic FEP) 

Longfin mako shark – North Pacific Unknown Unknown 

Oceanic whitetip shark – Tropical 

Pacific Unknown Unknown 

Salmon shark – North Pacific Unknown Unknown 

Silky shark – Tropical Pacific Unknown Unknown 

Western 

Pacific FMC 

American Samoa 

FEP 

American Samoa Coral Reef 

Ecosystem Multi-Species Complex Unknown Unknown 

Western 

Pacific FMC 

Mariana Archipelago 

FEP 

Guam Coral Reef Ecosystem MultiSpecies Complex Unknown Unknown 

Northern Mariana Islands Coral Reef 

Ecosystem Multi-Species Complex Unknown Unknown 

Western 

Pacific FMC 

Pacific Remote Islands 

Areas FEP 

Pacific Island Remote Areas Coral 

Reef Ecosystem Multi-Species 

Complex 

Unknown Unknown 

North Pacific 

FMC 

Gulf of Alaska 

Groundfish FMP Gulf of Alaska Shark Complex No Unknown 

North Pacific 

FMC 

Bering Sea/Aleutian 

Islands Groundfish FMP 

Bering Sea/Aleutian Islands Shark 

Complex No Unknown 

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Western 

Pacific FMC Hawaiian Archipelago 

FEP 

Hawaiian Archipelago Coral Reef 

Ecosystem Multi-Species Complex Unknown Unknown 

Totals: 

3 “yes”

16 “no”

15 “unknown”

5 “yes”

12 “no”

17 “unknown”

* LCS complex assessed in 2006. Since then, species-specific assessments have been performed only on individual 

species.
 

** Pelagic sharks are now being assessed individually. The only pelagic sharks that have not had a species-specific 

assessment are common thresher and oceanic whitetip sharks.
 

2014 Accomplishments in Response to Requirements of the Shark Finning Prohibition Act 

Report to Congress 

Section 6 of the Shark Finning Prohibition Act requires the Secretary of Commerce, in 

consultation with the Secretary of State, to provide to Congress an annual report describing 

efforts to carry out the Act. Report requirements are: 

1.	 Include a list that identifies nations whose vessels conduct shark finning and detail the 

extent of the international trade in shark fins, including estimates of value and 

information on harvesting, landings, or transshipment of shark fins. 

2.	 Describe and evaluate the progress taken to carry out this Act. 

3.	 Set forth a plan of action to adopt international measures for the conservation of sharks. 

4.	 Include recommendations for measures to ensure that the actions of the United States are 

consistent with national, international, and regional obligations relating to shark 

populations, including those listed under the Convention on International Trade in 

Endangered Species of Wild Flora and Fauna (CITES). 

NMFS’ accomplishments to carry out the Act are discussed below. An appendix including 

detailed information on U.S. shark management and enforcement (section 1), imports and 

exports of shark fins (section 2), international shark efforts (section 3), 2014 NOAA research on 

sharks (section 4), ongoing NOAA shark research (section 5), and references (section 6) has been 

posted online. A copy of this report and the appendix are available online at: 

http://www.nmfs.noaa.gov/sfa/laws_policies/sca/shark_finning_reports.html. 

Regarding the first requirement for this report, no reliable information exists to determine 

whether a nation’s vessels caught sharks on the high seas or conducted finning. However, data 

on the international trade of shark fins are available from the FAO, and data on U.S. imports and 

exports of shark fins are available from the U.S. Census Bureau. It is important to note that, due 

to the complexity of the shark fin trade, fins are not necessarily harvested by the same country 

from which they are exported. During 2014, shark fins were imported through the following 

U.S. Customs and Border Protection districts: Los Angeles, Miami, and New York. In 2014, 

countries of origin were New Zealand and Hong Kong (see table 2.1.1 in section 2 of the 

appendix). The mean value of imports per metric ton has consistently declined since 2010, with 

a more pronounced drop between 2011 and 2012. The unit price of $13,000 per metric ton in 

2014 was well below the mean value in 2008 of $59,000/mt. The majority of shark fins exported 

in 2014 were sent from the United States to Hong Kong, with smaller amounts going to China 

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(Taipei), China, and South Korea (Table 2.2.1). The mean value of exports per metric ton has 

decreased from $93,000/mt in 2010 to $52,000/mt in 2014, the lowest value since 2012, which 

was the year with the largest weight of exports, at 51 mt. Detailed information regarding imports 

and exports of shark fins can be found in section 2 of the appendix associated with this report. 

Consistent with the second requirement for this report to Congress, all recent shark-related 

management, enforcement, international, and research activities in support of the Shark Finning 

Prohibition Act are summarized in the appendix. Sharks in Federal waters are managed under 11 

fishery management plans under the authority of the MSA. The New England, Mid-Atlantic, 

Pacific, North Pacific, and Western Pacific fishery management councils have developed 10 of 

those plans. The Secretary of Commerce has developed the fishery management plan for 

oceanic sharks and other highly migratory species of the Atlantic Ocean, Gulf of Mexico, and 

Caribbean Sea as required by the MSA. 

During calendar year 2014, shark-related research took place at all six NOAA fisheries science 

centers and included research on data collection, stock assessments, biological information, 

incidental catch reduction, and post-release survival. Major management actions took place both 

domestically and internationally. Domestically, a final rule to list two populations of scalloped 

hammerhead sharks as threatened and two populations as endangered under the Endangered 

Species Act (ESA) was published in 2014. NMFS also issued two 12-month findings in 

response to petitions to list great hammerhead and dusky sharks under the ESA. In addition, 

violations of the Shark Finning Prohibition Act, and noncompliance with regulations designed to 

protect sharks, were detected, investigated, and referred for administrative prosecution in the 

Southeast and West Coast Enforcement Divisions. Details on specific shark management, 

enforcement, and education activities can be found in section 1 of the appendix, and information 

on 2014 shark research activities can be found in sections 4 and 5 of the appendix. 

In 2014, work continued to implement the requirements of the Shark Conservation Act of 2010 

through three separate rulemakings. NMFS published a final rule in January 2013, which 

amended the identification and certification procedures under the High Seas Driftnet Fishing 

Moratorium Protection Act and amended the definition of illegal, unreported, or unregulated 

fishing, consistent with the Shark Conservation Act. NMFS published a proposed rule in May 

2013 to implement provisions of the Shark Conservation Act that prohibit any person from 

removing any of the fins of a shark at sea, possessing shark fins on board a fishing vessel unless 

they are naturally attached to the corresponding carcass, transferring or receiving fins from one 

vessel to another at sea unless the fins are naturally attached to the corresponding carcass, 

landing shark fins unless they are naturally attached to the corresponding carcass, or landing 

shark carcasses without their fins naturally attached. NMFS is working to finalize that 

rulemaking. The Shark Conservation Act included a provision that allowed for limited at-sea fin 

removal of smooth dogfish caught in the Atlantic within 50 nautical miles of shore. On August 

7, 2014, NMFS published a proposed rule (79 FR 46217) to, among other things, implement this 

limited smooth dogfish exception. The comment period closed on November 14, 2014, and 

more than 500 comments were received. 

Regarding the third requirement for this report, the United States participated in the development 

of and endorsed the FAO International Plan of Action (IPOA) for the Conservation and 

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Management of Sharks (IPOA-Sharks). The IPOA-Sharks calls on all FAO members to adopt a 

corresponding National Plan of Action if their vessels conduct directed fisheries for sharks or if 

their vessels regularly catch sharks in non-directed fisheries. In addition to meeting the statutory 

requirement of the Shark Finning Prohibition Act, this annual Report to Congress serves as a 

periodic update of information called for in both the International and National Plans of Action 

for sharks. Consistent with the IPOA-Sharks, the United States developed a National Plan of 

Action for the Conservation and Management of Sharks in February 2001. Eleven other FAO 

members have developed national plans of action, and a regional plan of action for the 

Mediterranean Sea has been developed. 

Regarding the fourth report requirement, NMFS continues to work with the Department of State 

to promote the development of international agreements consistent with the Shark Finning 

Prohibition Act. The United States brings forward recommendations through bilateral, 

multilateral, and regional efforts. As agreements are developed, the United States implements 

those agreements. 

Throughout 2014, NMFS participated in meetings of international regional fishery management 

organizations. At many of these meetings, the U.S. delegations supported or introduced 

proposals to strengthen international shark management. International 2014 actions included 

supporting regional CITES workshops in Brazil and Senegal covering topics including CITES 

requirements, chain of custody, species identification using several visual guides, morphological 

tools (iSharkFin), and genetic techniques. The International Commission for the Conservation of 

Atlantic Tunas (ICCAT) recommendation for Atlantic shortfin mako requires parties to improve 

domestic data reporting systems and provide additional information to ICCAT about how they 

monitor and manage catches of shortfin mako sharks. The U.S. delegations to the International 

Scientific Committee for Tuna and Tuna-like Species in the North Pacific Ocean (ISC) and its 

Shark Working Group contributed to an updated stock assessment of blue shark in the North 

Pacific Ocean using two stock assessment approaches. The United States also contributed to the 

ISC’s progress on the first stock assessment for shortfin mako shark in the North Pacific Ocean, 

which is expected to be completed in 2015. The Western and Central Pacific Fisheries 

Commission adopted a conservation and management measure (CMM) 2014-05 for sharks that 

regulates the kind of fishing gear carried by longline vessels to reduce unintentional shark take. 

Also in 2014, the ISC and the Secretariat of the Pacific Commission conducted a stock 

assessment for North Pacific blue shark. Oceanic whitetip sharks, three species of hammerhead 

sharks, porbeagle sharks, and manta rays were also added to Appendix II of the Convention on 

International Trade in Endangered Species of Wild Fauna and Flora during 2013 and became 

effective in 2014. Also, at the 11th Meeting of the Conference of Parties of the Convention on 

the Conservation of Migratory Species of Wild Animals (CMS), a record number of 21 shark, 

ray, and sawfish species were listed on one or both of the CMS appendices. Detailed 

information on international shark-related efforts during calendar year 2014 is provided in 

section 3 of the appendix. 

References and internet sources used to compile this report can be found in section 6 of the 

appendix, available online at 

http://www.nmfs.noaa.gov/sfa/laws_policies/sca/shark_finning_reports.html 

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2015 Shark Finning Report to Congress 

Appendix 

Pursuant to the 

Shark Finning Prohibition Act 

(Public Law 106-557) 

U.S. Department of Commerce
 

National Oceanic and Atmospheric Administration
 

Prepared by the
 

National Marine Fisheries Service
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table of Contents 

Section 1: Management and Enforcement ...................................................................................... 1
 

1.1 Management Authority in the United States......................................................................... 1
 

1.2 2013 Conservation and Management Actions in the Atlantic Ocean................................... 2
 

Atlantic Highly Migratory Species Management ................................................................... 2
 

Shark Management by the Regional Fishery Management Councils and States.................... 5
 

1.3 Current Management of Sharks in the Pacific Ocean........................................................... 7
 

Pacific Fishery Management Council (PFMC)....................................................................... 7
 

North Pacific Fishery Management Council (NPFMC) ....................................................... 10
 

Western Pacific Fishery Management Council (WPFMC)................................................... 13
 

1.4 NOAA Enforcement of the Shark Finning Prohibition Act ............................................... 15
 

1.5 Education and Outreach...................................................................................................... 17
 

Section 2: Imports and Exports of Shark Fins ............................................................................ 19
 

2.1 U.S. Imports of Shark Fins ................................................................................................. 19
 

2.2 U.S. Exports of Shark Fins ................................................................................................. 20
 

2.3 International Trade of Shark Fins ....................................................................................... 20
 

Section 3: International Efforts to Advance the Goals of the Shark Finning Prohibition Act..... 27
 

3.1 Bilateral Efforts................................................................................................................... 27
 

3.2 Regional Efforts.................................................................................................................. 28
 

Northwest Atlantic Fisheries Organization (NAFO) ............................................................ 29
 

Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) ...... 29
 

Inter-American Tropical Tuna Commission (IATTC).......................................................... 30
 

International Commission for the Conservation of Atlantic Tunas (ICCAT) ...................... 30
 

Western and Central Pacific Fisheries Commission (WCPFC)............................................ 31
 

International Scientific Committee for Tuna and Tuna-like Species in the North Pacific 

Ocean (ISC) .......................................................................................................................... 31
 

3.3 Multilateral Efforts ............................................................................................................. 32
 

............................................................................................................................................... 32
 

Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)
 

World Customs Organization ............................................................................................... 33
 

Food and Agriculture Organization of the United Nations (FAO) ....................................... 33
 

United Nations (UN)) ........................................................................................................... 33
 

Convention on the Conservation of Migratory Species of Wild Animals (CMS)................ 33
 

Section 4: 2013 NOAA Research on Sharks ............................................................................... 34
 

4.1 Data Collection and Quality Control, Biological Research, and Stock Assessments......... 34
 

Pacific Islands Fisheries Science Center (PIFSC) ................................................................ 34
 

Southwest Fisheries Science Center (SWFSC)..................................................................... 37
 

Northwest Fisheries Science Center (NWFSC).................................................................... 40
 

Alaska Fisheries Science Center (AFSC, Auke Bay Laboratory) ........................................ 41
 

Northeast Fisheries Science Center (NEFSC) ...................................................................... 44
 

Southeast Fisheries Science Center (SEFSC) ....................................................................... 46
 

4.2 Incidental Catch Reduction................................................................................................. 48
 

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Pacific Islands Fisheries Science Center (PIFSC) ................................................................ 48
 

Southwest Fisheries Science Center (SWFSC)..................................................................... 49
 

4.3 Post-Release Survival ......................................................................................................... 50
 

Southwest Fisheries Science Center (SWFSC)..................................................................... 50
 

Northeast Fisheries Science Center (NEFSC) ...................................................................... 51
 

Southeast Fisheries Science Center (SEFSC) ....................................................................... 52
 

Section 5: Additional Information About Ongoing NOAA Shark Research............................... 54
 

Alaska Fishery Science Center (AFSC, Auke Bay Laboratory)........................................... 54
 

Northwest Fisheries Science Center (NWFSC).................................................................... 56
 

Southwest Fisheries Science Center (SWFSC).....................................................53
 

Pacific Islands Fisheries Science Center (PIFSC) ................................................................ 60
 

Southeast Fisheries Science Center (SEFSC) ....................................................................... 75
 

Northeast Fisheries Science Center (NEFSC) ...................................................................... 83
 

Section 6: References & Internet Information Sources ............................................................... 84
 

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Section 1: Management and 

Enforcement 

1.1 Management Authority in the United States 

The Magnuson-Stevens Fishery Conservation and Management Act (MSA) provides the legal 

authority for fisheries conservation and management in Federal waters and requires NMFS and 

the eight regional fishery management councils to take specific actions. State agencies and 

interstate fishery management commissions are bound by State regulators and, in the Atlantic 

region, by the Atlantic Coast Fisheries Cooperative Management Act. 

Development of fishery management plans (FMPs) is the responsibility of one or more of the 

eight regional fishery management councils, established under the MSA, as well as, the 

responsibility of the Secretary of Commerce in the case of Atlantic highly migratory species. 

Since 1990, shark fishery management in Federal waters of the Atlantic Ocean, Gulf of Mexico, 

and Caribbean Sea, excluding spiny dogfish, has been the responsibility of the Secretary of 

Commerce. Spiny dogfish in the Atlantic Ocean are managed by the New England Fishery 

Management Council (NEFMC) and the Mid-Atlantic Fishery Management Council (MAFMC). 

In the Pacific, three regional councils are responsible for developing fishery management plans 

for sharks: The Pacific Fishery Management Council (PFMC), the North Pacific Fishery 

Management Council (NPFMC), and the Western Pacific Fishery Management Council 

(WPFMC). The PFMC’s area of jurisdiction is the exclusive economic zone (EEZ) off 

California, Oregon, and Washington; the NPFMC covers Federal waters off Alaska, including 

the Gulf of Alaska and the Bering Sea/Aleutian Islands; and the WPFMC’s jurisdiction covers 

Federal waters around Hawaii, Guam, American Samoa, the Northern Mariana Islands, and other 

U.S. non-self-governing insular areas of the Pacific. 

In general, waters under the jurisdiction of the individual States extend from the shoreline out to 

3 miles (9 nautical miles off Texas, the west coast of Florida, and Puerto Rico); while U.S. 

waters under Federal management continue from the seaward boundary of each of the coastal 

States out to 200 nautical miles offshore except where intercepted by the EEZ of another nation. 

Management of elasmobranchs in State waters usually falls under the authority of State 

regulatory agencies, which are typically the marine division of the State fish and wildlife 

departments. Each State develops and enforces its own fishing regulations for waters under its 

jurisdiction, though federally permitted commercial fishermen in the Atlantic are required to 

follow Federal regulations regardless of where they are fishing, as a condition of the permit. 

While States set fishery regulations in their own waters, they are encouraged to adopt compatible 

regulations between State and Federal jurisdictions. Many coastal States promulgate regulations 

for shark fishing in State waters that complement or are more restrictive than Federal shark 

regulations for the U.S. EEZ. Given that many shark nursery areas are located in waters under 

State jurisdiction, States play a critical role in effective shark conservation and management. 

Cooperative management of the fisheries that occur in the jurisdiction of two or more States and 

Federal waters may be coordinated by an interstate fishery management commission. These 

commissions are interstate compacts that work closely with NMFS. Three interstate 

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commissions exist: the Pacific States Marine Fisheries Commission (PSMFC), the Atlantic 

States Marine Fisheries Commission (ASMFC), and the Gulf States Marine Fisheries 

Commission (GSMFC). The Atlantic Coast Fisheries Cooperative Management Act (ACFCMA) 

established a special management program between NMFS, the Atlantic coast States, and the 

ASMFC. Under this legislation, Atlantic States must comply with the management measures 

approved by this Commission, or risk a Federally-mandated closure by NMFS of the subject 

fishery (50 CFR part 697). NMFS is addressing the requirements of the Shark Conservation Act 

(SCA) of 2010 through three separate rulemakings. Two of these address domestic provisions of 

the SCA. A third rule, finalized in 2013, amended the identification and certification procedures 

under the High Seas Driftnet Fishing Moratorium Protection Act and amended the definition of 

illegal, unreported, and unregulated fishing. 

Rulemaking to Implement Domestic Provisions of the Shark Conservation Act of 2010 

On May 2, 2013, NMFS published a proposed rule (78 FR 25685) to implement provisions of the 

SCA that prohibit any person from removing any of the fins of a shark at sea, possessing shark 

fins on board a fishing vessel unless they are naturally attached to the corresponding carcass, 

transferring or receiving fins from one vessel to another at sea unless the fins are naturally 

attached to the corresponding carcass, landing shark fins unless they are naturally attached to the 

corresponding carcass, or landing shark carcasses without their fins naturally attached. NMFS 

proposed this action to amend existing regulations to make them consistent with the SCA. The 

public comment period was open for 91 days, and over 180,000 comments were received. 

Twelve states and territories have passed laws that prohibit some combination of the possession, 

sale, offering for sale, trade, or distribution of shark fins. In the proposed rule, NMFS noted that 

state or territorial shark fin laws may be preempted if they are inconsistent with the MagnusonStevens Act, as amended by the Shark Conservation Act. Since the publication of the proposed 

rule, NMFS has been engaged in discussions with states and territories with shark fin laws to 

determine whether the state’s or territory’s fin ban undermines federal shark management. These 

conversations are ongoing, and NMFS is working to finalize that rulemaking. 

The SCA included a provision that allowed for limited at-sea fin removal of smooth dogfish 

caught in the Atlantic within 50 nautical miles of shore. On August 7, 2014, NMFS published a 

proposed rule (79 FR 46217) to, among other things, implement this limited smooth dogfish 

exception. The comment period closed on November 14, 2014, and over 500 comments were 

received. 

1.2 2014 Conservation and Management Actions in the Atlantic Ocean 

Atlantic Highly Migratory Species Management 

On October 2, 2006, the 1999 FMP for Sharks of the Atlantic Ocean was replaced with the final 

Consolidated Atlantic Highly Migratory Species (HMS) FMP, which consolidated management 

of all Atlantic HMS under one plan, reviewed current information on shark essential fish habitat, 

required the second dorsal and anal fin to remain on shark carcasses through landing, required 

shark dealers to attend shark identification workshops, and included measures to address 

overfishing of finetooth sharks (71 FR 58058). This FMP manages several species of sharks 

(Table 1.2.1). The 2007–2014 commercial shark landings and the 2014 preliminary commercial 

shark landings are shown in Tables 1.2.2 and 1.2.3, respectively. In 2014, catch of Porbeagle in 

the Atlantic and catch of species in the aggregated large coastal sharks complex in the Gulf of 

Mexico exceeded the annual catch limits set for the stocks. 

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Table 1.2.1 U.S. Atlantic shark management units, shark species for which retention is 

prohibited, and data-collection-only species. 

Sharks in the Consolidated Atlantic HMS FMP 

Large Coastal Sharks (LCS) Small Coastal Sharks (SCS) 

Spinner 

Silky* 

Bull 

Blacktip 

Sandbar** 

Tiger 

Carcharhinus brevipinna 

Carcharhinus falciformis 

Carcharhinus leucas 

Carcharhinus limbatus 

Carcharhinus plumbeus 

Galeocerdo cuvier 

Finetooth 

Blacknose 

Atlantic sharpnose 

Bonnethead 

Carcharhinus isodon 

Carcharhinus acronotus 

Rhizoprionodon terraenovae 

Sphyrna tiburo 

Pelagic Sharks 

Common thresher Alopias vulpinus 

Nurse Ginglymostoma cirratum Oceanic whitetip Carcharhinus longimanus 

Lemon Negaprion brevirostris Shortfin mako Isurus oxyrinchus 

Scalloped hammerhead Sphyrna lewini Porbeagle Lamna nasus 

Great hammerhead 

Smooth hammerhead 

Sphyrna mokarran 

Sphyrna zygaena 

Blue Prionace glauca 

Smoothhound Sharks 

Smooth dogfish 

Florida smoothhound 

Gulf smoothhound 

Mustelus canis 

Mustelus norrisi 

Mustelus sinusmexicanus 

Prohibited Species 

Bignose Carcharhinus altimus Bigeye thresher Alopias superciliosus 

Galapagos Carcharhinus galapagensis Narrowtooth Carcharhinus brachyurus 

Dusky Carcharhinus obscurus Caribbean reef Carcharhinus perezii 

Night Carcharhinus signatus Smalltail Carcharhinus porosus 

Sand tiger Carcharias taurus Sevengill Heptranchias perlo 

White Carcharodon carcharias Sixgill Hexanchus griseus 

Basking Cetorhinus maximus Bigeye sixgill Hexanchus nakamurai 

Bigeye sand tiger Odontaspis noronhai Longfin mako Isurus paucus 

Whale Rhincodon typus Caribbean sharpnose 

Atlantic angel 

Rhizoprionodon porosus 

Squatina dumeril 

Deepwater and Other Species (Data Collection Only) 

Iceland catshark Apristurus laurussoni Green lanternshark Etmopterus virens 

Smallfin catshark Apristurus parvipinnis Marbled catshark Galeus arae 

Deepwater catshark Apristurus profundorum Cookiecutter shark Isistius brasiliensis 

Broadgill catshark Apristurus riveri Bigtooth cookiecutter Isistius plutodus 

Japanese gulper shark Centrophorus acus American sawshark Pristiophorus schroederi 

Gulper shark Centrophorus granulosus Blotched catshark Scyliorhinus meadi 

Little gulper shark Centrophorus uyato Chain dogfish Scyliorhinus retifer 

Portuguese shark Centroscymnus coelolepis Dwarf catshark Scyliorhinus torrei 

Kitefin shark Dalatias licha Smallmouth velvet Scymnodon obscures 

Flatnose gulper shark Deania profundorum dogfish 

Bramble shark Echinorhinus brucus Greenland shark Somniosus microcephalus 

Lined lanternshark Etmopterus bullisi Pygmy shark Squaliolus laticaudus 

Broadband dogfish Etmopterus gracilispinnis Roughskin spiny Squalus asper 

Caribbean lanternshark Etmopterus hillianus dogfish 

Great lanternshark Etmopterus princeps Blainville's dogfish Squalus blainvillei 

Smooth lanternshark Etmopterus pusillus Cuban dogfish Squalus cubensis 

Fringefin lanternshark Etmopterus schultzi 

*Not allowed for recreational harvest.
 

**Can only be harvested within a shark research fishery, and not allowed for recreational harvest.
 

3 
 

 

Table 1.2.2 Commercial landings for Atlantic large coastal, small coastal and pelagic 

sharks in metric tons dressed weight, 2007–2014. 

Source: Cortés pers. comm. (2014) and HMS eDealer database. 

Commercial Shark Landings (mt) 

Species Group 2007 2008 2009 2010 2011 2012 2013 2014 

Large Coastal 

Sharks 1,056 618 686 689 674 629 640 619 

Small Coastal 

Sharks 280 283 303 162 265 281 215 197 

Pelagic 

Sharks 118 106 91 141 141 142 118 163 

Total 1,454 1,007 1,080 992 1,080 1,052 973 979 

Table 1.2.3 Preliminary landings estimates in metric tons (mt) and pounds (lb) dressed 

weight (dw) for the 2014 Atlantic shark commercial fisheries. 

Landings are based on dealer data provided through the MHS eDealer databse. 

2014 Landings Estimates 

Management Groups 

Region 2014 Quota 

Estimated 

Landings in 

2014 

% of 2014 

Quota 

Blacktip Sharks 

Gulf of 

Mexico 

274.3 mt dw 

(604,626 lb dw) 

200.9 mt dw 

(442,882 lb dw) 73% 

Aggregated Large 

Coastal SharksA 

151.2 mt dw 

(333,828 lb dw) 

152.7 mt dw 

(336,631 lb dw) 101% 

Hammerhead Sharks 25.3 mt dw 

(55,722 lb dw) 

13.8 mt dw 

(30,447 lb dw) 55% 

Non-Blacknose Small 

Coastal SharksB 

68.3 mt dw 

(150,476 lb dw) 

73.5 mt dw 

(162,088 lb dw) 108% 

Blacknose sharks 1.8 mt dw 

(4,076 lb dw) 

1.4 mt dw 

(3,160 lb dw) 78% 

Aggregated Large 

Coastal SharksC 

Atlantic 

168.9 mt dw 

(372,552 lb dw) 

158.2 mt dw 

(348,733 lb dw) 94% 

Hammerhead Sharks 27.1 mt dw 

(59,736 lb dw) 

12.5 mt dw 

(27,586 lb dw) 46% 

Non-Blacknose Small 

Coastal SharksB 

264.1 mt dw 

(582,333 lb dw) 

104.7 mt dw 

(230,815 lb dw) 40% 

Blacknose sharks 17.5 mt dw 

(38,638 lb dw) 

17.4 mt dw 

(38,437 lb dw) 99% 

Shark Research Fishery 

(Aggregated LCS) No 

Regional 

Quotas 

50.0 mt dw 

(110,230 lb dw) 

26.5 mt dw 

(58,367 lb dw) 53% 

Shark Research Fishery 

(Sandbar only) 

116.6 mt dw 

(257,056 lb dw) 

54.2 mt dw 

(119,527 lb dw) 46% 

Blue Sharks No 273.0 mt dw 8.1 mt dw 3% 

4
 
 

 

 

 

 

 

 

 

 

Regional 

Quotas 

(601,856 lb dw) (17,806 lb dw) 

Porbeagle Sharks 1.2 mt dw 

(2,820 lb dw) 

2.9 mt dw 

(6,414 lb dw) 227% 

Pelagic Sharks Other 

Than Porbeagle or BlueD 

488 mt dw 

(1,075,856 lb dw) 

151.7 mt dw 

(334,329 lb dw) 31% AAggregated Large Coastal Sharks (LCS) in the Gulf of Mexico includes the following: silky, tiger, spinner, bull,
 

lemon, and nurse. B Non-blacknose small coastal sharks (SCS) include the following: Atlantic sharpnose, finetooth, and bonnethead
 C Aggregated Large Coastal Sharks (LCS) in the Atlantic includes the following: silky, tiger, blacktip, spinner, bull,
 

lemon, and nurse.

D Pelagic sharks other than porbeagle and blues include the following: shortfin mako, thresher, and
 

oceanic whitetip
 

Shark Stock Assessments and Overfishing/Overfished Status 

In 2014, stock assessments for Atlantic and Gulf of Mexico smoothhound sharks were begun 

under the 39th Southeast Data, Assessment, and Review (SEDAR 34) stock assessment. These 

stock assessments were not finalized until 2015. 

Observer Coverage 

Since 2002, observer coverage has been mandatory for selected bottom longline and gillnet 

vessels to monitor bycatch in the shark fishery and compliance with the 2000 Shark Finning 

Prohibition Act and requirements under the Marine Mammal Protection Act (MMPA) and 

Endangered Species Act (ESA). The data collected through the observer program is critical for 

monitoring takes and estimating mortality of protected sea turtles, seabirds, marine mammals, 

Atlantic sturgeon, and smalltooth sawfish. Data obtained through the observer program are also 

vital for conducting stock assessments of sharks and for use in the development of fishery 

management measures for Atlantic sharks. Gillnet observer coverage is also necessary to 

comply with the requirements of the 2007 Atlantic Large Whale Take Reduction Plan 

(ALWTRP) (72 FR 34632, 72 FR 57104). 

Atlantic Shark Endangered Species Act Updates 

In response to petitions from WildEarth Guardians (WEG) and the Natural Resources Defense 

Council (NRDC) to list the entire population of great hammerhead sharks (Sphyrna mokarran), 

the northwest Atlantic population, or any distinct population segments (DPSs) of great 

hammerhead sharks, as threatened or endangered under the ESA, NMFS published a positive 90­

day finding (78 FR 24701) on April 26, 2013, announcing that listing the species may be 

warranted. On June 11, 2014, NMFS announced a 12-month finding (79 FR 33509) and 

determined that the species is not comprised of DPSs and does not warrant listing at this time. 

NMFS concluded that the great hammerhead shark is not currently in danger of extinction 

throughout all or a significant portion of its range and is not likely to become so within the 

foreseeable future. 

On July 3, 2014, in response to a petition submitted by WEG and Friends of Animals, NMFS 

issued a final determination (79 FR 38213) to list the Central and Southwest (SW) Atlantic DPS 

and the Indo-West Pacific DPS of scalloped hammerhead shark (Sphyrna lewini) as threatened 

species under the Endangered Species Act (ESA). The determination also listed the Eastern 

Atlantic DPS and Eastern Pacific DPS of scalloped hammerhead sharks as endangered under the 

ESA. 

5
 
 

 

 

NMFS received a petition from Wild Earth Guardians (WEG) dated January 20, 2010, requesting 

that we list porbeagle sharks (Lamna nasus) throughout their entire range, or as Northwest 

Atlantic, Northeast Atlantic, and Mediterranean Distinct Population Segments (DPS) under the 

ESA, as well as designate critical habitat for the species. NMFS also received a petition from the 

Humane Society of the United States (HSUS), dated January 21, 2010, requesting that we list a 

Northwest Atlantic DPS of porbeagle sharks as endangered in the North Atlantic under the ESA. 

Information contained in the petitions focused on the species’ imperilment due to historical and 

continued overfishing; modification of habitat through pollution, climate change, and ocean 

acidification; failure of regulatory mechanisms; and low productivity of the species. On July 12, 

2010, we published a 90-day finding in the Federal Register (75 FR 39656) stating that neither 

petition presented substantial information indicating that listing porbeagle sharks may be 

warranted. Accordingly, a status review of the species was not initiated. In August 2011, the 

petitioners filed complaints in the U.S. District Court for the District of Columbia challenging 

our denial of the petitions (Case 1:11–cv–01414–BJR HUMANE SOCIETY OF THE UNITED 

STATES v. BLANK et al.). On November 14, 2014, the court published a Memorandum 

Opinion vacating the 2010 90-day finding for porbeagle shark, and ordering NMFS to prepare a 

new 90-day finding. The court entered final judgment on December 12, 2014. 

On December 15, 2014, in response to petitions from WEG and NRDC, NMFS determined that 

the Northwest Atlantic and Gulf of Mexico population of dusky shark constitutes a DPS, but 

does not warrant listing at this time (79 FR 74684). The finding concluded that the Northwest 

Atlantic and Gulf of Mexico DPS is not currently in danger of extinction throughout all or a 

significant portion of its range and is not likely to become so within the foreseeable future. 

Shark Management by the Regional Fishery Management Councils and States 

The Mid-Atlantic and New England Fishery Management Councils and NMFS manage spiny 

dogfish (Squalus acanthias), the only shark species managed by the Regional Fishery 

Management Councils in Federal waters off the Atlantic. These Councils manage spiny dogfish 

fisheries under the 2000 Spiny Dogfish FMP. Spiny dogfish products landed in the United States 

are almost entirely exported to Europe (meat) and Asia (fins). Most product is landed whole 

with fins attached, and dock prices average $0.20 per pound. The commercial quota for the 2014 

fishing year was 49 million pounds, but only about 23 million pounds were landed due to 

demand limitations. Spiny dogfish is not overfished or experiencing overfishing and was above 

its biomass target in 2014. 

A significant decline in spiny dogfish landings and exports occurred during 2013 (Figure 1.2.1), 

due to the detection of high concentrations of polychlorinated biphenyls (PCBs) in spiny dogfish 

meat at points of entry into the European Union (EU). The EU subsequently adjusted its PCB 

tolerances for US dogfish, and landings rebounded during the 2014 fishing year. 

6
 
 

 

 

 

 

 

 

 

 

Figure 1.2.1. History of US Atlantic spiny dogfish landings from 1989 – 2013. 

Coordinated State management of sharks is vital to ensuring healthy populations of Atlantic 

coastal sharks. The Atlantic States Marine Fisheries Commission developed and individual 

States implemented an Interstate Coastal Shark FMP in 2008. One goal of this FMP was to 

improve consistency between Federal and State management of sharks in the Atlantic Ocean. 

Complementary quotas were set in both State and Federal waters from 2010-2014. Amendment 

3 to the Spiny Dogfish FMP, which was implemented by NMFS in 2014, made further 

improvements in consistency by removing the seasonal allocation of the commercial quota, 

which effectively allows the states to take the lead on quota allocation. Amendment 3 also 

updated EFH for spiny dogfish, and made other administrative improvements to the FMP. 

1.3 Current Management of Sharks in the Pacific Ocean 

Pacific Fishery Management Council (PFMC) 

The PFMC’s area of jurisdiction is the EEZ off the coasts of California, Oregon, and 

Washington. The Pacific Fishery Management Council and NMFS manage sharks under the 

2004 U.S. West Coast HMS Fisheries FMP and the Pacific Coast Groundfish FMP which was 

approved in 1982 and most recently amended in 2010. Species included under the West Coast 

HMS FMP, are the common thresher and shortfin mako (sharks commercially valued but not 

primarily targeted in the West Coast–based fisheries), as well as blue sharks (Table 1.3.1). 

Amendment 2 to the West Coast HMS FMP and its supporting regulations (76 FR 56327) 

reclassified bigeye thresher and pelagic thresher sharks as ecosystem component species that do 

not require management. The West Coast HMS FMP also designates three shark species as 

prohibited (Table 1.3.1). If intercepted during HMS fishing operations, these species—great 

white, megamouth, and basking sharks—must be released immediately, unless other provisions 

for their disposition are established consistent with State and Federal regulations. 

7
 
 

 

 

 

 

 

 

 

 

 

 

Table 1.3.1 Shark species in the West Coast Highly Migratory Species Fishery 

Management Plan. 

West Coast Highly Migratory Species FMP 

Group Common name Scientific name 

Sharks Listed as 

Management Unit 

Species 

Common thresher 

Shortfin mako 

Blue shark 

Alopias vulpinus 

Isurus oxyrinchus 

Prionace glauca 

Sharks Included 

in the FMP as 

Ecosystem 

Component 

Species 

Pelagic thresher 

Bigeye thresher 

Alopias pelagicus 

Alopias superciliosus 

Prohibited 

Species 

Great white 

Basking shark 

Megamouth 

Carcharodon carcharias 

Cetorhinus maximus 

Megachasma pelagios 

Sharks within the West Coast HMS FMP are managed to achieve optimum yield (OY) set at a 

precautionary level of 75 percent of maximum sustainable yield (MSY). The precautionary 

approach is meant to prevent localized depletion of these vulnerable species. Blue, thresher and 

shortfin mako sharks are managed under the West Coast HMS FMP, and while blue and 

common thresher sharks are not overfished, the status of the shortfin mako sharks is unknown. 

The FMP proposed annual harvest guidelines for common thresher and shortfin mako sharks 

given the level of exploitation in HMS fisheries at the time the FMP was adopted (e.g., large 

mesh drift gillnet), and accounting for the uncertainty about catch in Mexico of these straddling 

stocks. High exploitation rates and their impact on HMS shark stocks, if not checked, could take 

decades to correct given the vulnerable life history characteristics of the species. In 2014, the 

International Scientific Committee for Tuna and Tuna-like Species in the North Pacific Ocean 

(ISC) produced a reassessment of blue sharks in the North Pacific Ocean (ISC 2014). The main 

differences between the 2014 assessment and the 2013 assessment were: 1) inclusion of revised 

CPUE series; 2) some time-series data was updated through 2012; 3) further examination of the 

effect of the Bayesian priors on the BSP model outcomes; and 4) use of the SS model to provide 

an alternative approach that could be compared to the production modeling. While uncertainties 

remain, results indicate that stock biomass and spawning biomass in 2011 (B2011 and SSB2011) 

were 65% and 62% higher than at MSY, respectively, and the annual fishing mortality in 2011 

(F2011) was estimated to be well below FMSY. 

In 2014, the ISC SHARKWG also began an assessment of the stock status of shortfin mako 

sharks for review at the 2015 ISC Plenary and the Western and Central Pacific Fisheries 

Commission (WCPFC) Science Committee (SC) meetings. The SHARKWG met in late 2014 

and early 2015 to compile data, and developed a fishery indicator analysis approach to use for 

the first assessment of this species in the North Pacific. The SWFSC is also involved in shark 

assessments outside of the ISC. In order to promote data collection for shark research in Mexico, 

the SWFSC and WCR are collaborating on multiyear efforts with Centro de Investigación 

8
 
 

 

 

Científica y de Educación Superior de Ensenada (CICESE), led by Dr. Oscar Sosa-Nishizaki. 

This collaboration is intended to coordinate artisanal fishing camp monitoring and sampling in 

Baja California, Mexico, and help advance cooperative stock assessment efforts with Mexico, 

U.S., and IATTC scientists. As a result of the sampling program, fishery data for pelagic sharks 

now includes some size and sex sampling as well as several years of species-specific catch 

information. Fishery data for common thresher sharks have been compiled and the first joint 

U.S.-Mexico stock assessment will be completed by SWFSC and Mexico scientists in 2015. 

The Pacific Coast Groundfish FMP, last amended in 2015, includes three shark species: leopard, 

soupfin, and spiny dogfish, in the groundfish management unit (Table 1.3.2). These shark 

species are mainly caught incidentally in groundfish fisheries and discarded at sea. In 2013, 

spiny dogfish were not overfished, but the status was unknown for soupfin and leopard sharks. 

As part of the PFMC’s biennial specifications process for 2015-16, soupfin shark was 

reclassified as an Ecosystem Component species, as it is not targeted, is not subject to 

overfishing or being overfished in the absence of conservation measures, and is not generally 

retained for sale or personal use. A separate OFL and ACL were also established for spiny 

dogfish, beginning in 2015. From 2006 through 2010, NMFS managed spiny dogfish using twomonth cumulative trip limits for both open access and limited entry fisheries. Since 2011, most 

of the limited-entry trawl fishery for groundfish has been managed under an individual quota 

program, in which vessels are held accountable for their total catch of all species managed with 

quota shares. However, landings of spiny dogfish by trawlers continue to be managed through a 

cumulative trip limit, now of 1-month duration. Landing limits for non-trawl vessels remain at 

two months. 

Table 1.3.2 Shark species in the groundfish management unit of the Pacific Coast 

Groundfish Fishery Management Plan. 

Pacific Coast Groundfish FMP 

Sharks Listed as Management Unit Species 

Common name Scientific name 

Soupfin shark (Tope) 

Spiny dogfish 

Leopard shark 

Galeorhinus galeus 

Squalus suckleyi 

Triakis semifasciata 

Shark catch data are obtained from commercial landings receipts, observer programs, and 

recreational fishery surveys. Landings data for the U.S. West Coast are submitted by the States 

to the Pacific Fisheries Information Network (PacFIN) and Recreational Fisheries Information 

Network (RecFIN) data repositories. Table 1.3.3 shows commercial shark landings for the West 

Coast from 2005 to 2014. Estimates of commercial discards, as well as catch in the at-sea hake 

fishery, are developed by the West Coast Groundfish Observer Program, at the NMFS Northwest 

Fisheries Science Center. Additional recreational data collection and estimation of recreational 

catch are also conducted by NMFS. Data from all of these sources are used for monitoring and 

management by the PFMC. Recreational shark fishing, primarily for common thresher and 

shortfin mako shark, is popular among anglers seasonally in Southern California waters. Data 

collected formerly through the Marine Recreational Fisheries Statistics Survey (MRFSS) and 

9
 
 

 

 

 

 

 

 

 

now through the California Recreational Fisheries Survey (CRFS) is used as the best available 

information regarding shark catch and effort in Southern California Waters. 

Table 1.3.3 Commercial Shark landings (round weight equivalent in metric tons) for 

California, Oregon, and Washington, 2005–2014. Source: PacFIN Database, data for 

the Pacific Fishery Management Council area extracted using the “Explorer” tool on 

August 26, 2015. 

Commercial Shark Landings (mt) for California, Oregon, and 

Washington 

Species Name 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 

Bigeye thresher shark 10 4 5 6 7 1 1 <1 1 1 

Blue shark 1 <1 10 <1 1 <1 <1 <1 <1 0 

Brown catshark -­ -­ -­ -­ -­ 11 4 14 1 1 

Common thresher 

shark 

179 160 204 147 107 96 76 68 66 40 

Leopard shark 13 11 11 3 2 3 2 3 1 3 

Pacific angel shark 12 15 8 12 12 9 10 10 11 8 

Pelagic thresher shark <1 <1 2 <1 <1 <1 -­ 1 6 6 

Shortfin mako 33 45 44 35 29 20 17 22 29 18 

Soupfin shark 26 30 17 8 5 3 3 2 1 2 

Spiny dogfish 468 394 425 638 264 230 393 215 160 150 

Other shark 5 4 2 2 2 3 1 2 1 2 

Unspecified shark 5 5 5 2 2 20 4 3 2 4 

Total 752 668 733 853 431 396 510 350 273 235 AThis extraction includes all commercial landings, in West Coast U.S. ports, of sharks caught in areas managed by 

the PFMC. This is a change from some prior years, in which West Coast landings of sharks caught in Alaska, 

Canada, and Puget Sound were included (via the use of PacFIN Report #307). This summary does not include 

estimates of commercial discards or any recreational catch. 

North Pacific Fishery Management Council (NPFMC) 

The NPFMC and NMFS manage fisheries in Federal waters off Alaska. Eleven shark species are 

found in the Alaskan waters (Table 1.3.4; Goldman 2012). NMFS monitors shark catch in 

season for Pacific sleeper, salmon, and spiny dogfish sharks and the remaining species of sharks 

are grouped into the “other/unidentified sharks”. Pacific sleeper, salmon, and spiny dogfish 

sharks are taken incidentally in Federal groundfish fisheries, while the other eight species are 

very rarely taken in any sport or commercial fishery. 

Table 1.3.4 North Pacific shark species. 

North Pacific shark species 

Common name Scientific name 

Pacific sleeper shark Somniosus pacificus 

Salmon shark Lamna ditropis 

10
 
 

 

 

 

 

 

 

 

 

Spiny dogfish shark Squalus suckleyi 

Brown cat shark Apristurus brunneus 

Basking shark Cetorhinus maximus 

Sixgill shark Hexanchus griseus 

Blue shark Prionace glauca 

Pacific angel shark Squatina californica 

White shark Carcharodon carcharias 

Common thresher shark Alopias vulpinus 

Soupfin shark Galeorhinus glaeus 

In Federal waters sharks are currently in a “bycatch only” status, which prohibits directed fishing 

for the species. In the Bering Sea/ Aleutian Islands (BSAI), most of the shark incidental catch 

occurs in the midwater trawl pollock fishery and in the hook-and-line fisheries for sablefish, 

Greenland turbot, and Pacific cod along the outer continental shelf and upper slope areas. In the 

Gulf of Alaska (GOA), most of the shark incidental catch occurs in the midwater trawl pollock 

fishery, non-pelagic trawl fisheries, and hook-and-line Pacific cod, sablefish, and halibut 

fisheries. The most recent estimates of the incidental catch of sharks in the BSAI and GOA are 

from 2014. These data are included in Chapter 20 in the 2014 BSAI and GOA Stock Assessment 

and Fishery Evaluation (SAFE) reports and the NMFS catch accounting system. Estimates of 

the incidental catch of sharks in the groundfish fisheries from 2004 through 2014 have ranged 

from 522 to 2,169 mt in the GOA and from 61 to 689 mt in the BSAI (Table 1.3.5). Very few 

sharks incidentally taken in the groundfish fisheries in the GOA and BSAI are retained. There 

has been no effort targeting sharks in the BSAI or GOA since 2006. 

Table 1.3.5	 Incidental catch and utilization (in metric tons) of sharks in the Gulf of Alaska 

and Bering Sea/Aleutian Islands commercial groundfish fisheries, 2004-2014. 

(Values are rounded to nearest metric ton)
 

Source: NMFS Catch Accounting System Data
 

Incidental Catch of Sharks (mt) - Gulf of Alaska 

Species 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 

Spiny dogfish 183 443 1,188 797 533 1,653 404 484 458 2,066 1,330 

Pacific 

sleeper shark 282 482 252 295 66 56 168 26 142 95 71 

Salmon shark 41 60 34 141 7 9 107 7 50 3 145 

Unidentified 

shark 39 69 83 107 12 24 9 5 10 6 6 

Total 545 1,054 1,557 1,340 618 1,742 688 522 660 2,169 1552 

% Retained 2.1 3.3 4.2 3.4 6.8 3.3 5.7 2.9 2.6 0.6 0.9 

Incidental Catch of Sharks (mt) - Bering Sea/Aleutian Islands 

Spiny dogfish 9 11 7 3 17 20 15 8 20 24 19 

Pacific 

sleeper shark 420 333 313 257 127 51 28 48 47 69 63 

Salmon shark 26 47 63 44 41 71 12 47 26 23 52 

11
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Unidentified 

shark 60 26 305 28 7 10 6 5 3 1 2 

Total 515 417 688 332 192 152 61 108 96 117 136 

% Retained 2.6 4.9 3.9 9.8 6.7 4.1 6.3 6.4 3.6 1.9 2.9 

In October 2010, NMFS issued a final rule to implement Amendments 95 and 96 to the BSAI 

FMP and Amendment 87 to the GOA FMP (75 FR 61639) to comply with statutory requirements 

for annual catch limits and accountability measures (under National Standard 1), and to rebuild 

overfished stocks. NMFS specified the NPFMC recommended overfishing levels (OFLs), 

acceptable biological catch (ABCs), and total allowable catch (TAC) amounts. Due to 

conservation concerns, the final rules to implement groundfish harvest specifications in the BSAI 

and GOA in 2014 and 2015 prohibited directed fishing for sharks in both management areas. In 

other groundfish fisheries open to directed fishing, the retention of sharks taken as incidental 

catch is limited to no more than 20 percent of the aggregated amount of sharks, skates, 

octopuses, and sculpins in the BSAI, and 20 percent of the aggregated amount of sharks, 

octopuses, squids, and sculpins in the GOA. 

At its December 2013 meeting, the NPFMC recommended OFLs, ABCs, and TACs for sharks in 

both the BSAI and GOA for the 2014 and 2015 fishing years. The GOA TAC was based in large 

part on the natural mortality and biomass estimates for spiny dogfish combined with an average 

historical catch (1997-2007) of other shark species, while the BSAI TAC was set at a value of 

100 mt, substantially less than that recommended ABC which was based on historical maximum 

catch (1997-2007) of all the shark species. Table 1.3.5 lists the recent historical catch of sharks 

in the BSAI and GOA. In 2014 the BSAI TAC was 225 t, and catch was 136 t. The 2014 GOA 

TAC was 5,989 t, and catch was 1,552 t. The most recent assessments for sharks are in Chapter 

20 to the 2014 SAFE reports for the BSAI and GOA, which is currently available online. 

The shark complexes in the BSAI and GOA are assessed biennially, with update only 

assessments in the off years, to coincide with the availability of new survey data. Thus, the most 

recent BSAI SAFE report was completed in 2013 and the most recent GOA SAFE report was 

completed in 2011 (a full assessment was not conducted in 2013 due to the government 

shutdown). In the BSAI, NMFS conducts surveys annually in the Eastern Bering Sea and 

triennially along the deeper slope area in the BSAI for all groundfish, including sharks. In the 

GOA, NMFS conducts surveys biennially for groundfish, including sharks. The most recent 

surveys were conducted in 2014 in the BSAI and in 2013 in the GOA, with the results 

incorporated into the SAFE reports for sharks. The next NMFS surveys are scheduled for 2015 

in the BSAI and GOA. 

The North Pacific Observer Program was restructured in 2013. As a result, observers are now 

deployed on smaller vessels and vessels fishing in the Pacific halibut Individual Fishing Quota 

fishery, which were previously unobserved. Details of the restructuring are provided in Faunce 

et al. (2014). The restructuring in essences created a new time series of catch, which more 

accurately reflects catch of sharks in both the GOA and BSAI. Analyses are ongoing to 

determine the overall impact of the new catch time series and how it effects the stock 

assessments. 

12
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Recreational shark fisheries 

The Alaska Department of Fish and Game (ADF&G) manages the recreational shark fishery in 

State and Federal waters under the Statewide Sport Shark Fishery Management Plan (5 AAC 

75.012), in effect since 1998. 

Recreational harvest of all shark species combined is estimated through a mail survey of sport 

fishing license holders. In 2014, an estimated 2,101 sharks of all species were harvested by the 

sport fishery in state and federal waters of Alaska (most recent estimate). The estimate is quite 

imprecise, with a coefficient of variation of about 35 percent. The Southcentral Region 

accounted for 64 percent of the harvest. The catch typically consists almost entirely of spiny 

dogfish and salmon shark. Although the vast majority of spiny dogfish are released, they are 

believed to be the primary species harvested. Salmon sharks are also taken occasionally by 

anglers targeting halibut. Catches of all other shark species are rare. 

Commercial shark fishing in State waters 

State of Alaska regulation 5 AAC 28.084 prohibits directed commercial fishing of sharks 

statewide, except for a spiny dogfish permit fishery (5 AAC 28.379) adopted by the Alaska 

Board of Fisheries for the Cook Inlet area in 2005. Sharks taken incidentally to commercial 

groundfish and salmon fisheries may be retained and sold provided that the fish are fully utilized 

as described in 5 AAC 28.084. The State limits the amount of incidentally taken sharks that may 

be retained to 20 percent of the round weight of the target species on board a vessel except in the 

Southeast District, where a vessel using longline or troll gear may retain up to a 35 percent 

bycatch of spiny dogfish (5AAC 28.174 (1) and (2)). In addition, in the East Yakutat Section 

and the Icy Bay Subdistrict salmon gillnetters may retain all spiny dogfish taken as bycatch 

during salmon gillnet operations (5AAC 28.174 (3)). All sharks landed must be recorded on an 

ADF&G fish ticket. No permits have been issued for the Cook Inlet spiny dogfish fishery since 

2006. 

Western Pacific Fishery Management Council (WPFMC) 

The WPFMC’s area of jurisdiction includes the EEZ around Hawaii, American Samoa, Guam, 

the Northern Mariana Islands, and the Pacific Remote Islands Areas (PRIA). The Western 

Pacific Fishery Management Council and NMFS conserve and manage sharks through five 

fishery ecosystem plans. The WPFMC’s Fishery Ecosystem Plan for Pacific Pelagic Fisheries of 

the Western Pacific Region identifies nine sharks as management unit species (Table 1.3.6). 

Five species of coastal sharks are listed in the fishery ecosystem plans for American Samoa, 

Hawaii, the Mariana Archipelago, and the Pacific Remote Islands Areas (Table 1.3.7) as 

currently harvested. 

The longline fisheries in the western Pacific, mostly in Hawaii and American Samoa, landed the 

vast majority of the sharks. Shark landings (estimated whole weight) by the Hawaii-based 

longline fisheries peaked at about 2,870 mt in 1999, largely due to the finning of blue sharks, 

which is now prohibited. A State of Hawaii law prohibiting landing shark fins without an 

associated carcass was passed in mid-2000 (Hawaii Revised Statutes 188.40-5). Shark landings 

have since decreased by almost 50 percent to 1,450 mt in 2000. With the subsequent enactment 

of the Federal Shark Finning Prohibition Act, shark landings since 2001 have been less than 200 

mt (Table 1.3.8). Landings in 2015 were approximately 58 mt, down from 105 mt in 2012, and 

13
 
 

 

 

 

 

 

 

 

were the lowest landings in recent history. Today, sharks are marketed as fresh shark fillets and 

steaks in Hawaii supermarkets and restaurants and are also exported to the U.S. mainland. 

Table 1.3.6 Sharks in the management unit of the Fishery Ecosystem Plan for Western 

Pacific Pelagic Fisheries (as amended December 2009). 

Western Pacific Pelagic Fisheries FEP 

Common name Scientific name 

Common thresher shark Alopias vulpinus 

Pelagic thresher shark Alopias pelagicus 

Bigeye thresher shark Alopias superciliosus 

Silky shark Carcharhinus falciformis 

Oceanic whitetip shark Carcharhinus longimanus 

Shortfin mako shark Isurus oxyrinchus 

Longfin mako shark Isurus paucus 

Salmon shark Lamna ditropis 

Blue shark Prionace glauca 

Table 1.3.7 Coastal sharks listed as management unit species and designated as currently 

harvested coral reef taxa in the four Western Pacific Fishery Ecosystem Plans. 

Other coastal sharks in the management unit of the FEP belonging to the families 

Carcharhinidae and Sphyrnidae are designated as potentially harvested coral reef taxa. 

Western Pacific Fishery Ecosystem Plans 

Sharks Listed as Management Unit Species and Designated as Currently 

Harvested Coral Reef Taxa 

Common Name Scientific Name 

American 

Samoa 

FEP 

Hawaii 

FEP 

Marianas 

FEP 

PRIA 

FEP 

Silvertip shark Carcharhinus albimarginatus X - X X 

Grey reef shark Carcharhinus amblyrhynchos X X X X 

Galapagos shark Carcharhinus galapagenis X X X X 

Blacktip reef shark Carcharhinus melanopterus X X X X 

Whitetip reef shark Triaenodon obesus X X X X 

The American Samoa longline fishery lands a small amount of sharks compared to Hawaii’s 

longline fisheries (Table 1.3.8). The pattern of shark landings by the American Samoa longline 

14 
 

 

 

 

 

 

 

 

fishery was similar to shark landings by the Hawaii-based longline fisheries and has remained 

low since 2011. The decline in shark landings by the American Samoa longline fishery is 

attributed to the Shark Finning Prohibition Act. 

Table 1.3.8	 Shark landings (in metric tons) from the Hawaii-based and American Samoabased pelagic longline fisheries, 2003–2014. 

Source: Pacific Islands Fisheries Science Center, Fisheries Research and 

Monitoring Division. Species 2004 2005

200620072008200920102011201220132014 

Hawaii- Blue shark 59 30 11 6 8 10 9 16 19 1 0 

based 

Longline 

Mako 

shark 66 106 95 127 130 119 92 65 66 51 50 

Fisheries Thresher 

shark 56 34 33 44 42 31 17 19 14 5 6 

Misc. 

shark 7 7 11 8 5 6 4 3 2 0 0 

Total 

shark 

landings 

188 177 151 186 186 166 122 102 101 57 56 

American 

Samoa 

Total 

shark 

landings 

1 <1 1 2 1 1 2 4 4 4 1 

1 2013 metric tons American Samoa sharks “estimated weight landed” (zero lbs registered/estimated as sold) 

Pacific Islands Region Endangered Species Act Scalloped Hammerhead Shark Listing 

On July 3, 2014, NMFS listed the Central and Southwest Atlantic DPS and the Indo-West 

Pacific DPS of scalloped hammered shark as threatened, and the Eastern Atlantic DPS and 

Eastern Pacific DPS of scalloped hammerhead sharks as endangered under the ESA (7 FR 

38214). 

1.4 NOAA Enforcement of the Shark Finning Prohibition Act 

The NOAA Office of Law Enforcement (OLE) has responsibility for enforcing the Shark 

Finning Prohibition Act of 2000 and implementing regulations. During calendar year 2014, 

violations of the SFPA, and noncompliance with regulations designed to protect sharks, were 

detected, investigated, and referred for administrative prosecution in the Southeast and West 

Coast Enforcement Divisions. Violations which were investigated included finning by U.S. 

domestic fishing vessels and illegal use of shark as bait. 

•	 In 2014, the owner and operator of the F/V Honey Bee were charged under the 

Magnuson-Stevens Act for failing to maintain sharks intact through offloading ashore. 

15
 
 

 

 

 

 

 

 

 

 

 

During a federal fisheries patrol in November of 2012, officers from the Florida Fish and 

Wildlife Conservation Commission (FWC) conducted an inspection of the F/V Honey 

Bee after it was located actively retrieving longline fishing gear from the water, 

approximately 100 miles from shore in the U.S. Exclusive Economic Zone (EEZ). FWC 

officers boarded the F/V Honey Bee and determined that the longline gear had been 

illegally baited with federally regulated species, including finfish and shark, which are 

required to be maintained intact through offloading ashore. The NOAA Office of the 

General Counsel – Enforcement Section (GCES) issued a Notice of Violation and 

Assessment (NOVA) penalty in the amount of $8,000.00 to the respondents. 

•	 A boarding team from the U.S. Coast Guard Cutter Staten Island conducted an inspection 

of a commercial fishing vessel in January of 2014. The vessel was located in the EEZ 

approximately thirty miles offshore of Oregon Inlet, NC. The USCG boarding team 

located three (3) pelagic sharks that had been harvested; one (1) thresher, and two (2) 

mako sharks. The thresher shark had been finned and all five fins were present, as well 

as the carcass. The vessel did not possess either a directed or incidental shark permit. In 

addition, numerous safety violations were discovered and the vessel’s voyage was 

terminated by the USCG. After consulting with GCES, the NOAA OLE issued a Written 

Warning to the vessel operator. A Written Warning is a citation that serves as official 

notice to the respondent, and affirms the violation. It does not assess a monetary penalty, 

but may be viewed by the GCES as a prior offense when prosecuting future violations. 

•	 NOAA GCES charged the owner and operator of the F/V Watersport under the 

Magnuson-Stevens Act for failing to maintain a shark in its proper form through 

offloading, by removing shark fins from the shark carcasses at sea. This investigation 

was initiated in December of 2011 after OLE had received a complaint through the 

NOAA Enforcement Hotline concerning a photograph that was found on the internet. 

The image detailed an individual aboard a commercial fishing vessel that was holding the 

tail section of a large swordfish that was positioned on the deck. Also on the deck, were 

what appeared to be, and later confirmed as mako shark fins that were harvested from 

several animals. A Notice of Violation and Assessment (NOVA) civil penalty in the 

amount of $5,015.00 was issued to the respondent. 

•	 The NOAA Office of the General Counsel – Enforcement Section (GCES) charged the 

owner and operator of the F/V Lucky Diamond, a commercial shrimp fishing vessel, for 

catching sharks, removing their fins, and returning the illegally finned carcasses to the 

sea. This violation was detected in August of 2011 when officers from the Louisiana 

Department of Wildlife and Fisheries (LDWF) were on a federal fisheries compliance 

patrol under OLE’s Joint Enforcement Agreement (JEA) program, and conducted a 

boarding of the F/V Lucky Diamond in the U.S. Exclusive Economic Zone (EEZ). 

During the course of the inspection, 146 individual shark fins were located onboard. 

There were no corresponding shark carcasses. In addition, the vessel operator did not 

possess a Highly Migratory Species (HMS) shark angling permit. The shark fins were 

seized as evidence and the vessel operator was cited by LDWF officers for illegally 

finning sharks and for failing to possess a required federal permit. A Notice of Violation 

and Assessment (NOVA) penalty in the amount of $15,000.00 was issued by NOAA 

GCES to the respondents for violating the Magnuson-Stevens Act. 

16
 
 

 

 

 

 

 

 

 

•	 A NOAA OLE special agent assisted officers from the California Department of Fish and 

Wildlife (CDFW) with the seizure of over 2,000 pounds of shark fins. On January 29, 

2014, wildlife officers from CDFW conducted a fish business inspection in San 

Francisco, and found shark fins for sale on the premises. The fins were possessed and 

also offered for sale in violation of California law. As part of the investigation, CDFW 

wildlife officers seized 2,138pounds of product and cited the owner for the violation. 

The California law that prohibits possession of shark fin for sale, went into effect in 

2011, but included a phase-in period to allow restaurants and other businesses to sell off 

remaining stock. As of July 1, 2013, no person may possess shark fins for sale in 

California. Wildlife officers from the CDFW are federally deputized under NOAA 

OLE’s Joint Enforcement Agreement (JEA) program in order to enforce federal fisheries 

laws. 

•	 NOAA GCES charged the owner and operator of the commercial fishing vessel F/V No 

Bull under the Magnuson-Stevens Act for illegally using shark bycatch as bait while 

fishing with longline gear in the EEZ. This concludes a joint investigation by the NOAA 

OLE and the Florida Fish and Wildlife Conservation Commission (FWC) that was 

initiated in 2010. In December of that year, officers from the FWC, while operating 

under OLE’s Joint Enforcement Agreement (JEA) Program, conducted an at-sea 

boarding and inspection of the F/V No Bull. The fishing vessel was observed hauling 

longline gear approximately 40 nautical miles offshore. During the inspection, FWC 

officers observed hooks baited with red grouper and shark. Numerous pieces of 

identifiable bait were seized as evidence. Federal regulations require finfish and shark in 

or from the Gulf Exclusive Economic Zone to be maintained intact through offloading 

ashore. The NOAA GCES issued a Notice of Violation and Assessment (NOVA) penalty 

in the amount of $8,000 to the respondents. This violation was eventually settled in the 

final amount of $7,200. 

1.5 Education and Outreach 

The U.S. National Plan of Action for the Conservation and Management of Sharks states that 

each U.S. management entity (i.e., NMFS, Regional Fishery Management Councils, Interstate 

Marine Fisheries Commissions, and States) should cooperate with regard to education and 

outreach activities associated with shark conservation and management. As part of the effort to 

implement the U.S. National Plan of Action, NMFS, OLE, and other U.S. shark management 

entities have completed the following actions: 

•	 In March of 2014, a NOAA enforcement officer traveled to Venice, LA to conduct 

education and outreach with area shark dealers. This was in response to a U.S. Coast 

Guard boarding and inspection of a bottom longline shark fishing vessel wherein multiple 

gear violations and sea turtle disentangling equipment deficiencies were documented. 

OLE provided guidance to industry members concerning specific regulations pertaining 

to sharks, as well as legal requirements for fishing gear, protected resources mitigation 

equipment, and permitting. 

17
 
 

 

 

 

 

 

 

•	 In October of 2014, a NOAA enforcement officer conducted education and outreach at a 

fishing tournament that was held in Destin, FL, with shark conservation highlighted. In 

addition, OLE worked with officers from the Florida Fish and Wildlife Conservation 

Commission (FWCC) to address a tournament complaint alleging that a tiger shark had 

been illegally caught in state waters. Further investigation disclosed that the tiger shark 

was legally harvested by a federally permitted vessel in the U.S. EEZ and eligible for 

entry in the Destin tournament. 

•	 To facilitate identification of Atlantic sharks, the HMS Management Division requires 

that all Federal Atlantic shark dealers attend a mandatory Atlantic Shark Identification 

Workshop at least once every three years. These free, monthly workshops provide 

hands-on training to help identify both processed and whole sharks to the species level. 

State and Federal fish and wildlife law enforcement officers also frequently attend these 

workshops, which are conducted throughout the entire Atlantic and Gulf of Mexico 

coasts. A total of 12 Atlantic Shark Identification Workshops were held in 2014. 

•	 The Greater Atlantic Regional Fisheries Office (GARFO) and the Northeast Fisheries 

Science Center (NEFSC) work together to provide the public with information about 

shark and skate species found in the Northwest Atlantic Ocean. This includes 

collaborating and coordinating media interviews with shark experts to highlight recent 

research as well as offering updated information about shark-related (i.e., spiny dogfish 

and skates) management actions. 

•	 In June 2014, the results of the collaborative GARFO, NEFSC, SEFSC, Massachusetts 

Division of Marine Fisheries, and University of Florida study on the distribution and 

increasing relative abundance of northwest Atlantic white sharks was published (Curtis et 

al. 2014) and received intense popular media coverage. The results were featured by over 

200 news outlets worldwide, and the contributing NMFS scientists were interviewed on 

national and regional television programs and numerous newspapers and internet news 

sites. 

•	 Staff from NMFS NEFSC regularly attend Northeast U.S. recreational shark fishing 

tournaments, captains meetings, and local sport fishing shows to inform participants on 

current shark management regulations and discuss and answer questions on current 

research. Annually, the NEFSC tagging booklet is updated, detailing tagging and 

recapture instructions, catch and release guidelines, research results, length and weight 

information, management regulations, and contact websites and telephone numbers. This 

booklet along with tags and identification guides and placards are made available to the 

fishing public and is also mailed to NMFS Cooperative Shark Tagging Program 

participants. Feedback is given to tournament officials on historic tournament landings to 

encourage further shark conservation measures and to facilitate better catch and release 

practices. 

•	 In 2014, NEFSC staff worked with a variety of partners (Concerned Citizens of Montauk, 

Montauk Chamber of Commerce, researchers from MADMF, Mote, OCEARCH, 

18
 
 

 

 

 

 

 

 

 

 

 

 

recreational sport fishermen, charter boat captains, marina owner, and the Guy Harvey 

Ocean Foundation) for an all-release, satellite tag shark tournament in Montauk, LI, NY 

called ‘Shark’s Eye’. Additionally, there was a 2-day public outreach event where much 

information was given out on NOAA Fisheries research. 

•	 Toby Curtis, staff at GARFO participated in a Twitter question and answer session during 

2014 Discovery shark week. This session gave the public the opportunity to interact with 

NMFS shark biologists in real time. 

•	 Drs. McCandless and Natanson, staff at NMFS NEFSC participated in a live online 

segment of io9’s “Ask the Expert” series in August 2014 regarding shark biology and 

behavior. This session gave the public an opportunity to interact with NMFS shark 

biologists in real time. 

•	 Dr. John Carlson participated in an informational video regarding shark attacks and 

sharks and their interactions with people. The video was posted on NOAA Fisheries 

Service YouTube channel. 

•	 Drs. Enric Cortés, John Carlson, and Simon Gulak participated in an informational video 

regarding the Northwest Atlantic Shark Cooperative Research Fishery. The video was 

posted on NOAA Fisheries Service YouTube channel. 

•	 The NMFS Office of Communications coordinates a national Shark Week campaign to 

which each Region and Science Center can contribute. 

Section 2: Imports and 

Exports of Shark Fins
 

The summaries of annual U.S. imports and exports of shark fins in Tables 2.1.1 and 2.2.1 are 

based on information submitted by importers and exporters to the U.S. Customs and Border 

Protection and to the U.S. Census Bureau as reported in the NMFS Trade database. 

2.1 U.S. Imports of Shark Fins 

During 2014, shark fins were imported through the following U.S. Customs and Border 

Protection districts: Los Angeles, Miami, and New York. In 2014, countries of origin (in order 

of importance based on quantity) were New Zealand and Hong Kong (Table 2.1.1). The mean 

value of imports per metric ton has consistently declined since 2010, with a more pronounced 

drop between 2011 and 2012. The unit price of $13,000.00 per metric ton in 2014 was well 

19
 
 

 

 

 

 

 

 

below the mean value in 2008 of $59,000.00 per metric ton. It should be noted that, due to the 

complexity of the shark fin trade, fins are not necessarily produced in the same country from 

which they are exported. In the United States, factors like availability of labor, overseas 

contacts, and astute trading can play a role in determining the locale from which exports are sent. 

2.2 U.S. Exports of Shark Fins 

The majority of shark fins exported in 2014 were sent from the United States to Hong Kong, 

with smaller amounts going to China, and Thailand (Table 2.2.1). The mean value of exports per 

metric ton has decreased from $80,000/mt in 2010 to $52,000/mt in 2014, the lowest value since 

2012 with the largest weight of 51 mt. Values continue to fluctuate in recent years with the 

2014 average at $52,000 mt compared to the 2013 average of $66,000/mt. 

2.3 International Trade of Shark Fins 

The Food and Agriculture Organization of the United Nations (FAO) compiles data on the 

international trade of fish. The summaries of imports, exports, and production of shark fins in 

tables 2.3.1, 2.3.2, and 2.3.3 are based on information provided in FAO’s FishStat database. The 

quantities and values in those tables are totals for all dried, dried and salted, fresh, or frozen 

shark fins. For 2013, global imports of shark fins were approximately 27,000 metric tons, the 

largest volume since 2009. In 2013, the average value of imports decreased to $7,230.00 per 

metric ton, while the average value of exports decreased to $12,637.00 per metric ton. Malaysia 

is the largest importer and Thailand is the largest exporter of shark fins for 2013. 

20
 
Table 2.1.1 Weight and value of dried shark fins imported into the United States, by country of origin.
 

Note: Weight is rounded to the nearest metric ton and value is rounded to thousands of dollars. (1) means that the
 

weight was less than 500 kilograms.
 

Source: U.S. Census Bureau 

Country 

2010 2011 2012 2013 2014 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Australia 0 0 7 85 0 0 0 0 0 0 

Canada 0 0 0 0 0 0 0 0 0 0 

China 21 422 12 732 16 131 10 75 0 0 

China, 

Hong Kong 11 695 15 700 2 39 3 89 1 43 

India 0 0 (1) 3 0 0 0 0 0 0 

Indonesia 0 0 0 0 0 0 (1) 8 0 0 

Japan (1) 3 0 0 0 0 0 0 0 0 

New Zealand 1 37 24 275 26 595 50 551 34 406 

South Africa 0 0 0 0 0 0 (1) 3 0 0 

Spain (1) 3 0 0 (1) 8 (1) 12 0 0 

Total 34 1800 58 1795 44 773 63 739 35 449 

Mean value $35,00/mt $31,000/mt $18,000/mt $12,000/mt $13,000/mt 

21
 
 

 

Table 2.2.1 Weight and value of dried shark fins exported from the United States, by country of destination.
 

Note: Data in table are “total exports” which is a combination of domestic exports (may include products of both 

domestic and foreign origin) and re-exports (commodities that have entered the United States as imports and not sold, 

which, at the time of re-export, are in substantially the same condition as when imported). (1) means that the weight was
 

less than 500 kilograms.
 

Source: U.S. Census Bureau
 

Country 

2010 2011 2012 2013 2014 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Metric 

Ton 

Value 

($1000) 

Canada 1 206 1 199 0 0 0 0 0 0 

China 2 335 5 895 (1) 60 1 71 1 130 

China, Hong Kong 39 2785 29 1,738 51 2,790 7 572 10 565 

China, Taipei (1) 6 0 0 0 0 4 135 7 193 

Egypt 0 0 0 0 0 0 0 0 0 0 

Germany 0 0 (1) 3 0 0 0 0 0 0 

Indonesia 0 0 0 0 0 0 0 0 0 0 

Japan 0 0 (1) 4 0 0 0 0 0 0 

Panama 0 0 0 0 0 0 0 0 0 0 

Poland (1) 22 3 86 0 0 0 0 0 0 

Portugal 0 0 0 0 0 0 0 0 0 0 

Thailand 0 0 0 0 0 0 0 0 0 0 

South Korea 0 0 0 0 0 0 0 0 1 91 

Turkey 0 0 0 0 0 0 (1) 10 0 0 

Total 42 3354 38 2925 51 2850 12 788 19 979 

Mean value $93,000/mt $77,000/mt $56,000/mt $66,000/mt $52,000/mt 

22
 
 

Table 2.3.1 Weight and value of shark fins imported by countries other than the United States.
 

Note: Weight is rounded to the nearest metric ton and value is rounded to thousands of dollars. (1) means that the weight 

was less than 500 kilograms.
 

Source: Food and Agriculture Organization of the United Nations, FishStat database, www.fao.org
 

Country 

2009 2010 2011 2012 2013 

Metric 

Ton 

Value 

($1000) 

Metric 

Ton 

Value 

($1000) 

Metric 

Ton 

Value 

($1000) 

Metric 

Ton 

Value 

($1000) 

Metric 

Ton 

Value 

($1000) 

Australia 7 902 6 1,128 16 915 27 1,074 23 947 

Brunei Darussalam 0 0 2 26 0 0 0 0 0 

Canada 184 6,217 107 6,487 104 6,351 275 3,347 243 3,541 

Chile 0 0 0 0 0 0 0 0 0 0 

China 732 4,490 183 968 160 1,065 113 1,434 39 339 

China, Hong Kong 9,395 247,087 9,891 296,167 10,332 345,469 8.283 219.391 5,408 121,136 

China, Macao 132 6,149 119 7,124 116 7,570 120 6,998 103 6,047 

China, Taipei 988 7,400 1,157 10,315 1262 - - - - -

Indonesia 150 1,120 237 970 101 1,762 53 1,029 41 349 

Laos (1) (1) 0 0 0 0 0 0 0 0 

Malaysia 1,331 3,809 3,676 10,369 3,489 10,248 3,013 9,833 18,048 17,612 

Myanmar 119 372 813 2,173 601 1,635 0 2 0 0 

North Korea (1) 24 69 267 (1) 8 - 0 0 2 

Peru 54 246 77 546 71 688 30 680 94 967 

Singapore 557 27,576 591 36,690 595 43,863 2,708 61,195 2,695 41,580 

South Korea 2 119 3 233 6 602 8 570 2 391 

Thailand 44 651 63 761 96 1,021 105 1,047 51 469 

Timor-Leste 112 29 96 24 131 29 0 0 0 0 

United Arab Emirates - - - - 26 1,209 16 330 16 113 

Total 13,807 306,191 17,090 374,238 17,096 422,435 14,751 306,930 26,763 193,493 

Mean value $22,171/mt $21,898/mt $24,710/mt $20,807/mt $7,230/mt 

23
 
 

Table 2.3.2 Weight and value of shark fins exported by countries other than the United States. 

Note: Data are for “total exports,” which is a combination of domestic exports (may include products of both domestic 

and foreign origin) and re-exports (commodities that have entered into a country as imports and not sold, which, at the 

time of re-export, are in substantially the same conditions as when imported). Weight is rounded to the nearest metric 

ton and value is rounded to thousands of dollars. (1) indicates that the weight < 500 kilograms. 

Source: Food and Agriculture Organization of the United Nations, FishStat database, www.fao.org 

Country 

2009 2010 2011 2012 2013 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Angola 4 282 7 527 19 873 15 797 6 439 

Argentina 84 3,376 63 2,766 70 2,312 3 87 6 49 

Bangladesh - - - - - - 24 196 6 41 

Brazil 85 2,338 49 1,376 59 2,109 39 1,777 31 1,294 

Brunei Darussalam - - - - 1 14 0 0 0 0 

Chile 5 194 1 46 3 167 4 223 3 115 

China 382 8,474 314 6,971 489 12,218 339 11,731 350 15,464 

China, Hong Kong 4,93 80,316 5,06 73,198 3,362 88,918 2,427 58,942 2,004 31,412 

China, Macao - - - - 8 444 31 1480 5 315 

Colombia 19 600 11 509 10 724 18 601 17 444 

Congo, Dem. Rep. of the - - - - 5 287 5 299 3 112 

Congo, Republic of 17 410 15 410 17 800 6 350 6 200 

Costa Rica 75 282 66 251 112 628 17 257 39 2851 

Cuba - - - - 4 204 4 182 4 118 

Ecuador 131 2,627 184 3,388 226 4,399 123 2,662 76 656 

Gabon - - 3 189 3 322 1 97 0 0 

Guinea 40 2,228 51 3,290 56 3,288 50 2,300 12 1,000 

Guinea-Bissau 2 160 - - - - 2 107 - -

India 107 12,504 98 8,946 135 8,310 168 13,211 51 3,086 

Indonesia 1,43 10,833 2,37 13,563 1,607 13,570 514 8,654 367 4,391 

Japan 164 6,824 164 8,591 131 8,759 116 5,081 103 2,434 

Kiribati 2 170 1 26 3 50 2 80 1 8 

Kuwait - - - - 1 23 (1) 17 0 0 

Liberia 4 415 8 679 3 317 1 50 1 59 

24
 
 

 

Table 2.3.2 Continued 

Country 

2009 2010 2011 2012 2013 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Metric 

ton 

Value 

($1000) 

Malaysia 347 1,394 260 1,614 417 1,981 298 1,542 687 3,563 

Maldives 9 57 4 22 0 0 0 0 0 0 

Marshall Islands 16 495 11 539 24 1,717 23 564 3 113 

Panama 47 3,310 37 1,457 24 1,481 43 906 58 458 

Papua New Guinea 12 1,288 17 1,220 25 2,200 1 268 8 658 

Peru 155 6,945 202 10,990 206 13,648 134 6,379 146 4,153 

Philippines 59 418 168 731 154 1125 83 740 213 1503 

Saudi Arabia 6 133 4 140 11 644 5 210 5 200 

Senegal 54 1500 35 1000 96 2870 63 2100 69 1300 

Seychelles 7 167 5 157 4 218 11 589 11 280 

Sierra Leone (1) 15 3 61 2 44 3 51 0 0 

Singapore 296 15,901 390 23,088 238 20,295 2260 42,199 2583 37,557 

Somalia - - - - - - - - 3 74 

South Korea 34 1,063 80 3,137 93 4,491 95 3,568 28 621 

Suriname 93 192 54 539 178 561 5 63 33 118 

Thailand 5,00 

5 24,795 7,14 1 32,545 7,72 3 40,245 5,45 5 27,008 3,89 2 20,868 

Togo 31 2,900 38 4,100 33 3,600 36 2,900 18 1,100 

Trinidad and Tobago 186 1,600 129 740 364 2,281 538 2,672 421 2,062 

United Arab Emirates 460 13,242 501 17,912 479 14,823 306 11,842 302 7,764 

Uruguay 16 269 12 188 10 87 9 94 5 32 

Venezuela 7 113 13 46 16 77 0 0 0 0 

Vietnam 347 1,540 98 504 223 1,105 (1) 20 8 295 

Yemen 260 10,736 431 13,942 347 12,428 54 369 90 322 

Total 14,940 220,106 18,106 239,398 16,991 274,657 13,331 213,265 11,674 147,529 

Mean value $14,733/mt $13,222/mt $16165/mt $15,998/mt $12,637 

25
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 2.3.3 Production of shark fins in metric tons by country other than the United 

States. 

Note: The production of shark fins represents the amount that a country processed 

at the fin level (not the whole animal level). NA = data not available. 

Source: Food and Agriculture Organization of the United Nations, FishStat 

database, www.fao.org 

Country 2009 2010 2011 2012 2013 

Bangladesh 276 955 - - 1 

Brazil 85 50 60 40 31 

Ecuador 131 184 226 118 75 

El Salvador 19 - - 11 9 

Guyana 132 126 75 208 209 

India 1,624 933 425 116 130 

Indonesia 1,367 2,320 1,395 500 310 

Maldives 9 4 - - -

Pakistan 80 83 91 96 99 

Senegal 27 18 35 91 54 

Singapore 218 192 210 220 210 

South Korea 34 80 93 95 28 

Sri Lanka 70 70 90 60 30 

Uruguay - 14 8 12 5 

Yemen 260 431 347 54 90 

TOTAL (mt) 4,332 5,460 3,055 1,621 1,281 

26
 
 

 

 

 

 

 

 

 

 

Section 3: International 

Efforts to Advance the 

Goals of the Shark Finning 

Prohibition Act 

The key components of a comprehensive framework for international shark conservation and 

management have already been established in global and regional agreements, as well as through 

resolutions and measures adopted by international organizations. These relevant mechanisms 

and fora have identified, adopted, and/or published detailed language, provisions, or guidance to 

assist States and regional fisheries management organizations (RFMOs) in the development of 

conservation and management measures for the conservation and sustainable management of 

sharks. Some of these mechanisms have created international legal obligations with regard to 

shark conservation and management, while others are voluntary. To that end, the United States 

continues to promote shark conservation and management by having ongoing consultations 

regarding the development of international agreements consistent with the Shark Finning 

Prohibition Act. Discussions have focused on possible bilateral, multilateral, and regional work 

with other nations. The Act calls for the United States to pursue an international ban on shark 

finning and to advocate improved data collection, including biological data, stock abundance, 

bycatch levels, and information on the nature and extent of shark finning and trade. Determining 

the nature and extent of shark finning is the key step toward reaching agreements to decrease the 

incidence of finning worldwide. To learn more about the United States’ international shark 

conservation activities go here. 

3.1 Bilateral Efforts 

The United States continues to participate in bilateral discussions with a number of States and 

entities to address issues relating to international shark conservation and management. Emphasis 

in these bilateral consultations has been on the collection and exchange of information, including 

requests for shark fin landings, transshipping activities, catch and trade data, stock assessments, 

and life history data collection. In addition, the United States continues to encourage other 

countries to implement the FAO’s International Plan of Action (IPOA) for the Conservation and 

Management of Sharks by finalizing, implementing and periodically updating their own National 

Plans of Action and to adopt a policy that requires all sharks to be landed with their fins 

naturally-attached. 

For example, in an effort to better identify and monitor shark product trade in light of new 

additions of several shark species to CITES Appendix II, NMFS in partnership with the U.S. 

Fish and Wildlife Service and several NGO partners have been working to build capacity in 

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Latin America, the Caribbean, and West Africa. These efforts have been broad covering topics 

from CITES requirements, chain of custody, and species identification using several visual 

guides, morphological tools (iSharkFin), and genetic techniques. With support from NMFS, the 

first regional CITES shark workshop was held in Brazil in December 2013. NMFS also 

supported a regional CITES shark workshop in Dakar, Senegal. The NMFS Office of 

International Affairs also awarded a grant to WWF for a pilot project to establish genetic 

identification labs in Ecuador and provide training on the use of genetic equipment. Ecuador 

was chosen due to their already well-established fishery monitoring program which will facilitate 

a more seamless implementation. Planning of the labs and training workshops is underway. 

In order to promote data collection in Mexico, the SWFSC and SWR are collaborating on 

multiyear efforts with Centro de Investigación Científica y de Educación Superior de Ensenada 

(CICESE) to coordinate artisanal fish camp monitoring and sampling in Baja California, Mexico 

and help advance cooperative stock assessment efforts with Mexico, U.S. and IATTC scientists. 

Sampling has provided valuable data for international assessment efforts through the 

International Scientific Committee for Tuna and Tuna-like Species in the North Pacific Ocean 

(ISC), as well as for a USA-Mexico partnership to assess the status of common thresher sharks. 

As a result of the sampling program, fishery data for pelagic sharks now includes some size and 

sex sampling as well as several years of species specific catch information. 

3.2 Regional Efforts 

The U.S. Government continues to prioritize shark conservation and management globally and 

work within RFMOs and other regional entities to facilitate shark research, data collection, 

monitoring, and management initiatives, as appropriate. In recent years, the United States has 

successfully led efforts to ban shark finning and implement shark conservation and management 

measures within a number of such organizations. Table 3.2.1 lists RFMOs and 

regional/multilateral programs in which the United States has worked to address shark 

conservation and management. Of the list in Table 3.2.1, The United States is a party to ICCAT, 

NAFO, CCAMLR,1

, WCPFC, IATTC, ISC, and the South Pacific Tuna Treaty. Eight of the 

organizations or programs listed have adopted finning prohibitions: ICCAT, NAFO, WCPFC, 

IATTC, IOTC, GFCM, SEAFO, and NEAFC. Recent activities or planning of the RFMOs to 

which the United States is a Party are discussed below as a supplement to last year’s Report to 

Congress. 

Table 3.2.1 Regional Fishery Management Organizations and Programs. 

1 CCAMLR is a conservation organization with an ability to manage fisheries within the area under its Convention 

and thus is included here as one of the regional fishery management programs. 

28
 
 

 

 

 

 

 

 

Regional Fishery Management Organizations and Programs 

•

•

•

•

•

•

•

•

•

•

•

•

•

Northwest Atlantic Fisheries Organization (NAFO) 

Commission for the Conservation of Antarctic Marine Living Resources 

(CCAMLR) 

Inter-American Tropical Tuna Commission (IATTC) 

International Commission for the Conservation of Atlantic Tunas (ICCAT) 

Western and Central Pacific Fisheries Commission (WCPFC) 

Indian Ocean Tuna Commission (IOTC) 

South East Atlantic Fisheries Organization (SEAFO) 

General Fisheries Commission for the Mediterranean (GFCM) 

North East Atlantic Fisheries Commission (NEAFC) 

Commission for the Conservation of Southern Bluefin Tuna (CCSBT) 

Treaty on Fisheries Between the Governments of Certain Pacific Island 

States and the Government of the United States of America (South 

Pacific Tuna Treaty) 

International Scientific Committee for Tuna and Tuna-like Species in the 

North Pacific Ocean (ISC) 

South Pacific Fisheries Commission (SPRFMO) 

Northwest Atlantic Fisheries Organization (NAFO) 

The NAFO Fisheries Commissions maintains a ban on shark finning in all NAFO-managed 

fisheries and mandated the collection of information on shark catches. The NAFO Fisheries 

Commission was the first regional fisheries management organization to establish a total 

allowable catch (TAC) for a directed elasmobranch fishery, but the first TAC was too high. The 

United States successfully negotiated a series of reductions since 2010 and the TAC (at 7,000 

metric tons) is now consistent with scientific advice. 

Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) 

Since 2006, CCAMLR has prohibited directed fishing on shark species in the Convention Area, 

other than for scientific research purposes. CCAMLR requires that any bycatch of shark, 

especially juveniles and gravid females, taken accidentally in other fisheries, shall, as far as 

possible, be released alive. The conservation measure with these requirements is silent on shark 

finning. 

In 2011 and 2013, the United States proposed a revision of the conservation measure to require 

that any sharks retained be landed with fins naturally attached to discourage the finning of sharks 

incidentally caught and improve the opportunities to collect data of such sharks. In 2014, the 

United States was joined by Brazil, Chile, and the European Union in making the proposal. The 

proposal has been met with strong support from many members but consensus has yet to be 

29
 
 

 

 

 

 

 

 

 

 

 

reached. The United States re-tabled the proposal, modified with an explicit prohibition of shark 

finning, for the 2015 annual meeting with Australia, Brazil, Chile, and European Union as cosponsors. 

Inter-American Tropical Tuna Commission (IATTC) 

In 2005, the IATTC adopted Resolution C-05-03, which placed controls on shark finning by 

applying a five percent fin-to-carcass weight ratio requirement. For several years, IATTC 

proposals have been submitted to replace current controls on shark finning in Resolution C-05­

03 with a prohibition on the retention of shark fins that are not naturally attached to the carcass 

until the first point of landing. The United States supported such a proposal, sponsored by the 

EU in 2014, but the Commission could not reach consensus. 

In 2013, the IATTC adopted a United States sponsored Resolution that prohibited, among other 

things, the intentional setting of purse seine nets on whale sharks. These prohibitions went into 

effect on July 1, 2014. The IATTC scientific staff presented summary information for 

hammerhead shark at the 2014 meeting of the Scientific Advisory Committee, but did not have 

enough data to complete the stock assessment. A summary of available information on 

hammerhead sharks caught in the eastern Pacific Ocean (EPO) indicated that there is not enough 

data to conduct statistical analyses for the artisanal fisheries, and there is scarce information on 

the longline fisheries. The purse seine bycatch data shows an overall declining trend in catch for 

hammerhead sharks in the EPO. 

Similarly, the IATTC scientific staff has been unable to conduct a stock assessment for silky 

shark in the EPO due to a lack of historical catch data. Updated stock status indicators for silky 

shark, presented during the 2014 meeting of the IATTC Scientific Advisory Committee suggest 

that the northern and southern stocks in the EPO are in decline. A silky shark management 

measure, similar to that adopted by the WCPFC in 2013 and ICCAT in 2011, has been proposed 

at IATTC meetings since 2012. The EU sponsored a silky shark proposal in 2014 to prohibit 

retention of silky shark. Although the United States strongly supported the proposal, the IATTC 

could not achieve consensus. 

International Commission for the Conservation of Atlantic Tunas (ICCAT) 

At the 2014 ICCAT Annual meeting, the United States co-sponsored a proposal to require that 

all sharks be landed with their fins naturally attached. The list of co-sponsors was expanded to 

include: Belize, Brazil, Ghana, EU, Panama, Sao Tome & Principe, Senegal, South Africa, 

Trinidad & Tobago, Guatemala, Egypt, Cote d’Ivoire, Gabon and the United States. As in past 

years, no consensus could be reached, but the increasing number of co-sponsors indicates 

growing support among some other ICCAT parties for a fins-attached approach. The issue is 

expected to be reconsidered at ICCAT’s 2015 Annual Meeting. Proposals relating to porbeagle 

sharks were also circulated, but were not adopted by the Commission. 

A recommendation for Atlantic shortfin mako requires parties to improve domestic data 

reporting systems and provide additional information to ICCAT about how they monitor and 

manage catches of shortfin mako sharks. 

30
 
 

 

 

 

 

 

 

Western and Central Pacific Fisheries Commission (WCPFC) 

At its 8th Regular Session of the Commission in March 2012, the Commission added the whale 

shark to the list of key species. In 2012, based on a U.S proposal, the WCPFC adopted a 

conservation and management measure (CMM) for oceanic whitetip sharks, prohibiting retention 

on board, transshipment, and landing of the species. At its 9th Regular Session of the 

Commission in December 2012, the Commission adopted a CMM prohibiting intentional sets by 

purse seine vessels in the vicinity of whale sharks. In 2013, WCPFC adopted a CMM that 

prohibits retaining on board, transshipping, storing on a fishing vessel, or landing any silky shark 

caught in the Convention Area, in whole or in part, in the fisheries covered by the Convention. 

In addition, the measure requires the release of any silky shark as soon as possible after it is 

brought alongside the vessel, and to do so in a manner that results in as little harm to the shark as 

possible. The measure is very similar to one adopted in 2012 for oceanic whitetip shark. In 

2014, NMFS issued a proposed rule for domestic implementation of the oceanic whitetip shark, 

whale shark, and silky shark CMMs and solicited public comment. 

Stock assessments for the North Pacific blue shark were completed in 2014. The Scientific 

Committee 10 (SC10) recommended that though it was not likely that the North Pacific blue 

shark was overfished or experiencing overfishing, that catch and effort data should be closely 

monitored for this species. SC10 also recommended that the Commission consider the analysis 

of longline shark mitigation methods to reduce catch rates and mortality of all sharks, and called 

for SC11 to review the development of whale shark safe release guidelines for longliners and 

purse seiners. 

At SC10, Secretariat of the Pacific Community Oceanic Fisheries Program issued a report on the 

progress implementing the Shark Research Plan (SRP), announcing that the SRP had 

successfully completed five stock assessments on WCPFC key shark species, planned a six stock 

assessment, an indicator analysis for all key shark species, and catch history estimations for 

several key species. WCPFC contractors also presented their development of Limit Reference 

Points for elasmobranchs at SC10. 

International Scientific Committee for Tuna and Tuna-like Species in the North Pacific 

Ocean (ISC) 

The 14th ISC Plenary, held in Taipei, Chinese-Taipei from 16-21 July 2014, was attended by 

members from Canada, Chinese Taipei, Japan, Korea, and the United States, as well as the 

Western and Central Pacific Fisheries Management Commission and the North Pacific Marine 

Science Organization. The Plenary reviewed results, conclusions, new data and updated 

analyses of the Shark Working Group. The Plenary endorsed the findings that the North Pacific 

blue shark is not overfished nor experiencing overfishing based on an updated assessment 

conducted using both a Bayesian surplus production model and an age-structured fully-integrated 

model (Stock Synthesis). The Plenary noted the strides the SHARKWG had made in 

incorporating best available scientific information into stock assessment work, enhanced stock 

assessment reports and the increased transparency in the Working Group’s efforts. The ISC 

SHARKWG’s work plan for 2015 includes completing the first shortfin mako shark (Isurus 

31
 
 

 

 

 

 

oxyrinchus) assessment and advancing research on fishery data, assessment methods and shortfin 

mako and blue shark life history. The SHARKWG held three meetings in 2014 to work on the 

updated North Pacific blue shark stock assessment and to advance shortfin mako fishery and life 

history data compilation. The SHARKWG also sponsored its second Shark Age and Growth 

Workshop. The Age and Growth Workshop and final blue shark assessment data preparatory 

meeting were held in January 2014 in La Jolla, United States. The blue shark assessment 

meeting was held in June 2014 in Keelung, Chinese-Taipei. The shortfin mako data preparatory 

meeting was held in November 2014 in Puerto Vallarta, Mexico. Active participants in the 

meetings have included Chinese Taipei, Japan, Mexico, the United States, IATTC, WCPFC and 

the Secretariat of the Pacific Community (SPC). 

3.3 Multilateral Efforts 

The U.S. Government continues to work within other multilateral fora to facilitate shark 

research, data collection, monitoring, and management initiatives, as appropriate. Table 4.3.1 

lists these multilateral fora. Of the list in Table 4.3.1, the recent activities for five organizations 

are discussed below as a supplement to last year’s Report to Congress. 

Table 3.3.1 Other multilateral fora. 

Other Multilateral Fora 

• Convention on International Trade in Endangered Species of Wild Fauna and 

Flora (CITES) 

• World Customs Organization (WCO) 

• Food and Agriculture Organization of the United Nations (FAO) 

• United Nations General Assembly (UNGA) 

• Convention on the Conservation of Migratory Species of Wild Animals (CMS) 

• International Union for Conservation of Nature (IUCN) 

• World Summit on Sustainable Development 

• International Council for the Exploration of the Sea (ICES) 

• Asia Pacific Economic Cooperation Forum and the Convention on Migratory 

Species (APEC) 

Convention on International Trade in Endangered Species of Wild Fauna and Flora 

(CITES) 

CITES has taken a number of actions to address the international trade of sharks and rays and 

help ensure that it is sustainable. Most recently, at the 16th Meeting of the Conference of the 

Parties (CoP16) to CITES, which was held in Bangkok, Thailand in March 2013, several 

commercially harvested shark and ray species were listed in Appendix II of CITES. The newly 

listed shark species include: oceanic whitetip shark, three species of hammerhead sharks 

(scalloped, great, and smooth), porbeagle shark, and manta rays. The effective date for these 

32
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

listings was September 14, 2014. Shark species already listed in Appendix II of CITES include 

the basking shark, whale shark, and great white shark. 

Prior to CoP16, all sawfishes (Pristidae) were listed in Appendix I of CITES, with the exception 

of Pristis microdon. At CoP16, CITES Parties adopted a proposal submitted by Australia to 

transfer this species from Appendix II to Appendix I. The proposal was put forward to provide 

the same protection to freshwater sawfish provided to other species of the Pristidae family and 

help facilitate enforcement due to look-alike issues. 

World Customs Organization (WCO) 

Related to actions taken in CITES and RFMOs to increase protection and enhance the 

monitoring and trade of commercially-exploited shark species, the WCO’s Harmonized System 

Review Subcommittee considered a Food and Agriculture Organization (FAO) proposal 

supported by the United States that would assist countries in tracking international trade in shark 

fins of several commercially-important species, including porbeagle shark, oceanic whitetip 

shark, hammerhead sharks, and blue shark. The FAO proposal would have established global 

harmonized system tariff codes to permit the monitoring of trade in shark fins for these 

commercially significant shark species. However, the proposal for species-specific codes did not 

receive sufficient support among WCO members to advance during the current 2017 review 

cycle. Although the proposed species-specific codes were not adopted, aspects of the FAO 

proposal that were successful at the WCO will help improve the monitoring of shark products in 

trade by establishing separate codes for fresh, frozen, prepared, and preserved forms of shark 

fins, among other changes. The next opportunity for WCO consideration of this proposal may 

take place during the upcoming 2022 review cycle. 

Food and Agriculture Organization of the United Nations (FAO) 

The FAO maintains it’s International Plan of Action for the Conservation and Management of 

Sharks (IPOA-Sharks), which is understood to include all species of sharks, skates, rays, and 

chimaeras of the class Chondrichthyes. The IPOA-Sharks calls on all FAO members to adopt a 

corresponding National Plan of Action if their vessels conduct directed fisheries for sharks or if 

their vessels regularly catch sharks in non-directed fisheries. Twelve FAO members have 

developed national plans of action, including the United States, and a regional plan of action for 

the Mediterranean Sea has been developed. 

United Nations (UN) 

The United States continues to work within the United Nations system (UN) process to develop 

specific calls to States and RFMOs to strengthen conservation and management measures for 

sharks. The United States has worked with other countries to propose and successfully adopt 

language and recommendations specific to sharks in the annual UN General Assembly (UNGA) 

sustainable fisheries resolutions, including some aimed at reducing bycatch and improving data 

collection. Since 2005, provisions have been adopted every year that call on States and RFMOs 

to significantly improve the conservation and management of sharks, including a call for sharks 

to be landed with their fins naturally attached. 

Convention on the Conservation of Migratory Species of Wild Animals (CMS) 

33
 
 

 

 

 

 

 

The 11th Meeting of the Conference of Parties was held November 4-9, 2014, in Quito, Ecuador. 

A record number of 21 shark, ray, and sawfish species (proposed by Kenya, Egypt, Fiji, Costa 

Rica and Ecuador) were listed on one or both of the CMS appendices. The United States was 

active in the expansion of CMS work on shark conservation. Also, an adopted resolution on 

shark and ray conservation urges all Parties to enact legislation or regulations requiring that 

sharks be landed with all fins naturally attached, in order to combat the practice of removing 

shark fins and discarding the remainder of the shark carcass at sea. It also urges Parties to 

develop National Plans of Action for Sharks which apply to a nation’s fishing fleet on the high 

seas, as well as in national waters. The documents from the meeting can be found at: 

http://www.cms.int/en/meeting/eleventh-meeting-conference-parties-cms#cop11-documents. 

In February 2010, the United States, along with 10 other States signed a global Memorandum of 

Understanding (MOU) for Migratory Sharks under the auspices of the Convention on Migratory 

Species. The United States is one of 36 Signatories, including 35 national governments and the 

European Union. The MOU aims to coordinate international action on the threats faced by 

sharks and works to improve their species conservation status. The MOU came into effect 

March 1, 2010 and it initially covers great white, basking, whale, porbeagle, shortfin mako, 

longfin mako, and the Northern Hemisphere population of spiny dogfish, but more species can 

be added later. 

Section 4: 2013 NOAA 

Research on Sharks 

Large predators such as sharks are a valuable part of marine ecosystems. Many shark species are 

vulnerable to overfishing because they are long-lived, take many years to mature, and only have 

a few young at a time. To manage sharks sustainably, we need information about their biology 

and the numbers caught (either as target species, incidentally, or as bycatch) to make sure their 

populations are not depleted. NMFS Fisheries Science Centers are investigating shark catch, 

abundance, age, growth, diet, migration, fecundity, and requirements for habitat. Additional 

research aims to identify fishing methods that minimize the incidental catch of sharks and/or 

maximize the survival of captured sharks after release. A summary of the research completed in 

2013 is presented here, but more complete descriptions of ongoing research taking place in each 

region is found in Appendix 5. 

4.1 Data Collection and Quality Control, Biological Research, and Stock 

Assessments 

Pacific Islands Fisheries Science Center (PIFSC) 

Insular Shark Surveys 

Densities of insular sharks have been estimated at most of the U.S. island possessions within the 

Tropical Central, Northern, and Equatorial Pacific on mostly biennial (now triennial) surveys 

34
 
 

 

 

 

 

 

 

 

 

 

 

 

conducted by the PIFSC Coral Reef Ecosystem Division since 2000. These estimates include 

surveys of major shallow reefs in the Northwestern Hawaiian Islands, the main Hawaiian 

Islands, and the Pacific remote island areas, American Samoa, Guam and the Commonwealth of 

the Northern Marianas Islands, Johnston Atoll, and Wake Atoll. 

Although 11 species of shark have been observed during Coral Reef Ecosystem Division surveys 

only four species are typically recorded by towed divers in sufficient frequency to allow 

meaningful analyses: grey reef shark (Carcharhinus amblyrhynchos), Galapagos shark 

(Carcharhinus galapagensis), whitetip reef shark (Triaenodon obesus), and blacktip reef shark 

(Carcharhinus melanopterus). 

Spatial analyses of data up to 2011 showed a highly significant negative relationship between 

gray reef and Galapagos shark densities and proximity to human population centers (e.g., proxy 

for potential fishing pressure and other human impacts). Even around islands with no human 

habitation but within reach of populated areas, gray reef and Galapagos shark densities are 

significantly lower. Trends in whitetip and blacktip reef shark numbers are similar but less 

dramatic (I.D. Williams et al., 2011; Nadon et al., 2012). More recent data is entirely consistent 

with those findings. In 2013 and 2014, deployment of baited and un-baited remote underwater 

video cameras to measure fish and shark abundance levels, including extending surveys into 

deeper waters (30-100m) may help add to the understanding of these population trends. Possible 

explanations for these patterns are currently being investigated. 

Growth rates of Tiger Shark in Hawaii 

PIFSC, in collaboration with the University of Hawai’i, Hawai’i Institute of Marine Biology, 

used mark/recapture data to estimate growth rates and maximum size for tiger sharks 

(Galeocerdo cuvier) in Hawai’i. Results found that tiger sharks in Hawaii grow twice as fast as 

previously thought, on average reaching 340 centimeters total length (TL) by age 5, and attaining 

a maximum size of 403 centimeters TL. The maximum likelihood growth model indicated that 

the fastest growing individuals attain 400 centimeters TL by age 5, and the largest reach a 

maximum size of 444 centimeters TL. The largest shark captured during the study was 464 

centimeters TL but individuals greater than 450 centimeters TL were extremely rare (0.005% of 

sharks captured). It was concluded that tiger shark growth rates and maximum sizes in Hawai’i 

are generally consistent with those in other regions, and hypothesized that a broad diet may help 

them to achieve this rapid growth by maximizing prey consumption rates (Meyer et al., 2014). 

Maximum age and missing time in shark vertebrae: the limits and validity of age estimates 

using bomb radiocarbon dating 

The aim of this work was to provide an overview of how bomb radiocarbon dating can work for 

shark vertebrae with some insight on how the method can fall short of expectations (Andrews et 

al., 2014). Bomb radiocarbon dating has become a common tool in determining valid measures 

of age for large shark species. In most cases, estimates of age were made by counting growthband pairs in vertebrae and usually in the corpus calcareum of vertebral cross-sections. These 

estimates of age have been either supported or refuted using measured radiocarbon values 

(reported as ∆14C) that are equated to a year-of-formation, and subsequently compared to an 

appropriate ∆14C reference record. While the approach seems straightforward, the application is 

not, and an effective ageing project may require some significant assumptions that are sometimes 

35
 
 

 

 

 

 

 

 

 

 

 

 

 

 

overlooked. Two of the most important considerations are the sources of carbon available to the 

vertebrae and the use of a valid ∆14C reference to provide validated age estimates. Recent 

findings for some species indicate the vertebrae cease growth, and as a consequence, ages have 

been underestimated by decades (i.e. sand tiger shark, Carcharias taurus). However, proper 

alignment of the ∆14C measurements from vertebral samples to the ∆14C reference record does 

not always provide well-defined ages and many are still considered estimates that require some 

assumptions (i.e. white shark, Carcharodon carcharias). 

Validated lifespan of sand tiger shark Carcharias taurus from bomb radiocarbon dating in the 

western North Atlantic and southwestern Indian Oceans 

Bomb radiocarbon analysis of vertebral growth bands was used to validate lifespan for sand tiger 

sharks, Carcharias taurus, from the western North Atlantic (WNA) and southwestern Indian 

Oceans (SIO). Visual counts of vertebral growth bands were used to assign age and estimate 

year of formation (YOF) for sampled growth bands in eight sharks from the WNA and two 

sharks from the SIO. Carbon-14 results were plotted relative to YOF for comparison with 

regional Δ14C reference chronologies to assess the accuracy of age estimates. Results from the 

WNA validated vertebral age estimates up to 12 years, but indicated ages of large adult sharks 

were underestimated by 11-12 years. Age was also underestimated for adult sharks from the SIO 

by 14-18 years. Validated lifespan for C. taurus individuals in this study reached at least 40 

years for females and 34 years for males. Findings indicate the current age-reading methodology 

is not suitable for estimating the age of C. taurus beyond approximately 12 years. Future work 

will investigate alternate ageing methods to determine whether vertebrae of C. taurus record age 

throughout ontogeny, or cease to be a reliable indicator at some point in time. This work was the 

first to report the Δ14C values for marine vertebrates from the SIO and the first to report vertebral 

age estimates for C. taurus outside of the Atlantic Ocean (Passerotti et al., 2014). 

White Shark in NE Pacific 

Age validation studies of large shark species using bomb radiocarbon (Δ14C) dating have 

revealed that the growth of vertebrae can cease in adults. In a previous study of white sharks 

(Carcharodon carcharias) of the northeastern Pacific Ocean the latest growth material (leading 

edge of the corpus calcareum) was assigned a known date of formation assumed to coincide with 

the individual’s date of capture. This perspective prevented the assignment of older years of 

formation (a shift in age) to this material, leading to complicated results and no validated age 

estimates. A reanalysis of the Δ14C data, in light of the recent findings for other species, has led 

to a validated lifespan estimate exceeding 30 years for white sharks of the northeastern Pacific 

Ocean (Andrews and Kerr, 2014). 

Deep water dogfish finspines 

Vertebrae of most deep-water sharks are too poorly calcified to record visible growth bands and 

therefore are not useful for age determination. Most dogfish species (Order Squaliformes) 

possess dorsal finspines and several recent studies have shown that these structures offer 

potential for age determination. Age validation should be central to any age determination study, 

yet to date no age and growth study of deep-water sharks has included a complete validation of 

age estimates. In this study, PIFSC sought to age two deep-water dogfish species by analyzing 

210Pb and 226Ra incorporated into the internal dentin of the finspines. These radiometric age 

estimates were compared with counts of internal growth bands observed in the finspines. A pilot 

36
 
 

 

 

 

 

 

 

 

 

 

 

study indicated that dorsal finspines of Centroselachus crepidater are too small and thus offer 

insufficient mass for the radiometric techniques employed in this study. For ageing larger 

finspines of Centrophorus squamosus, the lead–radium disequilibria method (ingrowth of 

210Pb from 226Ra) was found to be inapplicable due to exogenous uptake of 210Pb in the 

finspine. Therefore, to approximate age, we measured the decay of 210Pb within the dentin 

material at the tip of the finspine, which is formed in utero, relative to the terminal material at the 

base of the finspine. Results with this method proved to be inconsistent and did not yield reliable 

age estimates. Hence the use of 210Pb and 226Ra for radiometric age determination and 

validation using dorsal finspines from these deep-water dogfishes was deemed unsuccessful. 

This outcome was likely due to violations of the consistent, life-long isotopic uptake assumption 

as well as the provision that the finspine must function as a closed system for these 

radioisotopes. Future improvements in analytical precision will allow for smaller samples to be 

analyzed, potentially yielding a better understanding of the fate of these radioisotopes within 

finspine dentin throughout the life of the shark (Cotton et al., 2014). 

Southwest Fisheries Science Center (SWFSC) 

Abundance Surveys 

Juvenile Shortfin Mako (Isurus oxyrinchus) and Blue Shark (Prionace glauca) Survey 

In 2014, the SWFSC conducted its twenty first juvenile shark survey for mako and blue sharks 

since 1994. The 2014 annual abundance survey was completed between 25 June and 14 July 

aboard F/V Ventura II. 28 survey sets were completed and a total of 5,719 hooks were deployed 

during survey sets. Average surface water temperature recorded at the beginning of each survey 

set was 69.8 °F (21.03 °C), which is the third highest in survey history. Preliminary data indicate 

that the nominal survey catch rate was 0.03 per 100 hook-hours for blue sharks and 0.429 per 

100 hook-hours for shortfin mako. Survey catch totaled 124 fish; four (4) different species were 

caught including shortfin mako shark, blue shark, pelagic ray, and opah. 

Neonate Common Thresher Shark (Alopias vulpinus) Survey 

The common thresher shark pre-recruit index and nursery ground survey was initiated in 2003 to 

develop a fisheries-independent index of pre-recruit abundance and has been conducted in each 

year since. In 2014, SWFSC scientists and volunteers conducted the survey aboard the F/V 

Outer Banks. 49 longline sets were made in relatively shallow, nearshore waters and a total of 

4,900 hooks were fished during the 18-day cruise. A total of 247 fish across a range of species 

were sampled during the survey. 285 thresher sharks were captured. Most of these sharks were 

injected with oxytetracycline and tagged with a combination of conventional tags for movement 

and stock structure, and plastic dorsal tags containing return information for the age and growth 

study. The preliminary survey data indicate that the average nominal catch rate by set was 1.58 

thresher sharks per 100 hook-hours, which is down from the previous year. The nominal catch 

rate in 2014 was the second lowest since the survey began in 2006 and the recent five-year trend 

is downward. 

Electronic Tagging Studies 

Since 1999, SWFSC scientists have used data logging tags and satellite technology to 

characterize the essential habitats of large pelagic fish to better understand how populations 

might shift in response to changes in environmental conditions on short or long time scales; 

37
 
 

 

 

 

 

 

sharks tagged are primarily blue sharks, shortfin mako, and common thresher sharks, while other 

species are tagged opportunistically. In recent years, the SWFSC has collaborated with Mexican 

colleagues at Centro de Investigación Científica y de Educación Superior de Ensenada 

(CICESE), Canadian colleagues at the Department of Fisheries and Oceans Pacific Biological 

Station in Nanaimo, British Columbia, and the Tagging of Pelagic Predators program on shark 

tagging. 

In 2014, a number of sharks were released with electronic tags in support of several collaborative 

projects. Four shortfin mako and two blue sharks were tagged with satellite-linked radio position 

tags (SPOTs). In addition, in collaboration with Guy Harvey Institute and a recreational angler 

in the SCB, one 215 centimeters TL mako was tagged with a SPOT in October 2014. Of the tags 

deployed since 2012, 7 were still reporting in late 2014 (Figure 1). 

Figure 4.1.1 Tracks of seven shortfin mako sharks tagged since 2012 that were still 

reporting at the end of 2014. Different colors represent different animals. 

All SPOT and PSAT data for mako sharks tagged in the Southern California Bight between 2002 

and 2013 are currently being analyzed and a manuscript is being drafted. Preliminary analysis of 

SPOT tagged sharks with tracks longer than 6 months indicates that mako sharks frequented the 

waters of the Southern California Bight from July to October followed by dispersion to the north, 

south and offshore. Tags which recorded data for more than 12 months showed that 77% of 

tracked makos returned to the Southern California Bight the following summer. 

Age Validation Studies 

Age and growth of mako, common thresher, and blue sharks are being estimated from band 

formation in vertebrae. In addition to being important for studying basic biology, accurate age 

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and growth curves are needed in stock assessments. SWFSC scientists are validating ageing 

methods for these three species based on band deposition periodicity determined using 

oxytetracycline (OTC). Annual research surveys provide an opportunity to tag animals with 

OTC. When the shark is recaptured and the vertebrae recovered, the number of bands laid down 

since the known date of OTC injection can be used to determine band deposition periodicity. 

Since the beginning of the program in 1997, more than 3,500 individuals have been injected with 

OTC. During the 2014 SWFSC shark surveys, 109 shortfin makos, 134 thresher, and 35 blue 

sharks were injected with OTC and released. 

The Shark Working Group (SHARKWG) of the International Scientific Committee for Tuna and 

Tuna-like Species in the North Pacific Ocean (ISC) has developed a collaborative research plan 

to address uncertainties about age and growth of pelagic sharks. As part of the plan, 

participating national scientists have collected and shared samples from blue and shortfin mako 

sharks for a reference collection covering a large range of size classes for both species. The plan 

to conduct an ISC SHARKWG assessment of North Pacific shortfin makos in 2015 led to a focus 

on mako age and growth during 2014. Published reports of differing growth and band pair 

deposition rates between member labs have led participating scientists to examine the 

consistency of their counts on a sample of validated mako vertebrae. Images of OTC injected 

vertebrae from Wells et al. (2013) were chosen as the vertebrae to be used in this inter-laboratory 

count review. Once potential sources of counting error have been mitigated, participating 

national scientists will move forward with the ageing of mako shark vertebrae from the reference 

collection. Ultimately these efforts will lead to an improved growth model for shortfin makos in 

the North Pacific. 

In July of 2014, a large adult male mako which had been injected with OTC in 2008 was 

recaptured after more than 6 years at liberty (2,196 days). This represents the first recapture of a 

large adult male mako injected with OTC and subsequently recaptured in the northeastern Pacific 

after an extended period at liberty. Originally measured at 194 centimeters fork length (FL), the 

animal measured 217 centimeters (FL) upon recapture, indicating that over a six year period the 

animal had grown 23 centimeters, an average of 3.8 centimeters per year. This is well below 

estimated growth rates for juvenile makos (27-36 centimeters between their first and second 

summer and 20-29 centimeters in the following year). Previous ageing work on makos in the 

northeastern Pacific has indicated that juveniles deposit band pairs on their vertebrae at a rate of 

two band pairs per year (Wells et al., 2013). The band pair count from this adult animal clearly 

indicates that, post OTC injection, the shark displayed annual band pair deposition (5+ bands in 

six years). Based on the juvenile age validation work done by Wells et al. (2013), the results 

from this animal indicate that male makos experience a shift in deposition rates from two band 

pairs per year as juveniles, to one band pair per year as adults. Proper age determination and 

accurate growth models are important components of a stock assessment. A shift in band pair 

deposition rates will affect growth models (length-at-age) for shortfin mako in the northeast 

Pacific and consequently, estimates of age-at-maturity and longevity. More research will be 

needed to corroborate the timing of this shift in band pair deposition in males, and determine if 

the same shift occurs in females. 

Work continued on age validation of common thresher sharks. During 2014, 134 common 

threshers were injected with OTC. Since 1998, a total of 1,594 common thresher sharks ranging 

39
 
 

 

 

 

 

 

 

 

 

in size from 45 to 240 centimeters FL have been injected with OTC. Vertebrae from 60 of these 

sharks (size range at tagging: 63-145 centimeters FL) have been returned with an average timeat-liberty of 352 days. Of those, 26 of these samples were from individuals at liberty for over 10 

months with a maximum time-at-liberty of 1,389 days (3.8 years). An abstract describing the 

preliminary results and conclusion that common thresher deposit one vertebral band pair per year 

was presented at the ICES 5th International Otolith Symposium in October 2014. 

Record Shortfin Mako Shark Studied 

Predatory sharks can be difficult to study, especially for the larger size classes which are 

infrequently encountered and rarely landed in commercial and recreational fisheries. In the 

Northeastern Pacific Ocean, shortfin mako sharks are important predators, and while data are 

increasing for smaller size classes, there is a paucity of data regarding large adults. On 3 June 

2013, a record-breaking female shortfin mako shark (total length = 373 centimeters, mass = 

600.1 kilograms) was captured by a recreational angler off Huntington Beach, California, and 

was subsequently donated to the SWFSC and California State University Long Beach for 

research. Samples of various tissue types were collected and analyzed to gain more information 

about the shark’s anatomy, physiology, ecology, and life history. This rare opportunity allowed 

for the collection of important data and contributes to our knowledge about the life history 

characteristics of large shortfin mako sharks. In 2014 the results from the dissection and 

subsequent analyses were prepared for publication. Analyses of tissue isotopes, contaminants 

and stomach contents suggest a high trophic level and a significant reliance on coastal waters in 

and around the Southern California Bight. Mercury and contaminant concentrations were far 

above FDA limits for consumption (Lyons et al 2014). 

Population Genetics Studies 

An understanding of stock structure is important in order to make accurate assumptions for stock 

assessments and to develop effective management objectives that take the population range, 

distribution, and life history into account. Various genetic analyses are useful to help identify 

differentiation between and within presumed stocks. DNA samples were collected during 

research cruises in 2014 from 116 shortfin makos, 104 blue sharks, 139 common threshers, 5 

soupfins (Galeorhinus galeus), 4 leopard sharks (Triakis semifasciata), one brown smoothhound 

(Mustelus henlei) and 5 pelagic stingrays (Pteroplatytrygon violacea). Additional samples were 

obtained by fishery observers on commercial drift gillnet trips. Sample processing continued to 

examine stock structure for a number of shark species including shortfin mako, common 

thresher, silky (Carcharhinus falciformis), and pelagic thresher sharks. 

A study of pelagic thresher sharks throughout the Pacific identified strong genetic heterogeneity 

among populations (Cardeñosa et al. 2014). Two distinct populations were identified on either 

side of the Pacific with a high degree of spatial overlap in the central Pacific and near complete 

segregation of groups on either side. Analyses of nuclear data suggest there is little to no gene 

flow between these populations. Given the discrete geographic range of these populations and 

their reproductive isolation, it’s possible that this may represent the early stages of speciation. 

Northwest Fisheries Science Center (NWFSC) 

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Monitoring and Assessment Activities 

The NWFSC conducts and supports several activities addressing the monitoring and assessment 

of sharks along the West Coast of the United States and in Puget Sound. The Pacific Fishery 

Information Network (PacFIN) serves as a clearinghouse for commercial landings data, 

including sharks. In addition, the At-Sea Hake and West Coast Groundfish Observer Programs 

collect data on shark species caught on vessels selected for observer coverage. 

The NWFSC conducts annual trawl surveys of the West Coast, designed primarily to acquire 

abundance data for West Coast groundfish stocks. The tonnages of all shark species collected 

during these surveys are documented. In the past, the survey program conducted numerous 

special projects in recent years to help researchers acquire data and samples necessary for 

research on various shark species. Since 2002, the survey has collected biological data and 

tissue samples from spiny dogfish, including dorsal spines, which can be used to age the fish. 

Movement Research 

Through 2012, the NWFSC conducted extensive research on localized movements and seasonal 

migrations of three West Coast sharks: the bluntnose sixgill (Hexanchus griseus), broadnose 

sevengill (Notorynchus cepedianus), and northern spiny dogfish (Squalus suckleyi) (Andrews et 

al. 2007, 2009, 2010; Levin et al. 2012; Williams et al. 2011, 2012). These studies suggested 

that the population of sixgill sharks in Puget Sound is largely juveniles that remain resident for 

several years, while mature females appear to enter Puget Sound to pup. Active tracking 

methods revealed individual sixgill shark home range sizes and regular diel vertical migration 

patterns. Sevengill sharks made extensive use of coastal estuaries and shelf waters along the 

West Coast, and their movements and habitat use were related to season, sex, and size. Sevengill 

sharks appeared to display site fidelity, returning to the same areas of the same estuaries in 

several consecutive years. Puget Sound dogfish appear to undergo seasonal migrations, 

departing to waters along the West Coast in winter and spring months. 

Ongoing Sample Collection and Methods Development for Molecular Shark Species 

Identification 

The Marine Forensics Laboratory, currently uses mitochondrial DNA sequencing to identify the 

species of suspected sharks seized by agents of Federal and State law enforcement agencies, and 

continues to develop morphological methods to triage which fins need more costly genetic 

analysis. Sample collection and research to expand the number and range of shark species 

sequenced for a diagnostic DNA fragment is continuing. In 2014, several shark and ray species 

were added to the marine forensics archive of vouchers, and the NOAA Office of Law 

Enforcement submitted several shark fin cases to the NWFSC Forensics Laboratory for 

identifications. 

Alaska Fisheries Science Center (AFSC, Auke Bay Laboratory) 

Stock Assessments of Shark Species Subject to Incidental Harvest in Alaskan Waters 

Stock assessments are currently completed on the shark species most commonly encountered as 

incidental catch: Pacific sleeper sharks (Somniosus pacificus), spiny dogfish (Squalus suckleyi), 

and salmon sharks (Lamna ditropis). In both the Gulf of Alaska (GOA) and Bering Sea/Aleutian 

Islands (BSAI) fishery management plans, sharks are managed as a complex. Directed fishing 

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for all sharks is prohibited. In the BSAI, the shark complex is managed with catch limits based 

on historical maximum catch. In the GOA, catch limits for the complex are the sum of 

individual species recommendations: spiny dogfish catch limits are based on survey biomass 

estimates and the remaining species are based on historical average catch. Stock assessments are 

summarized annually and are available online (see Tribuzio et al. 2014a and 2014b, or the most 

recent North Pacific Groundfish Stock Assessment and Fishery Evaluation Reports. 

Migration and Habitat Use of Spiny Dogfish 

Spiny dogfish (Squalus suckleyi) are a small species of shark, common in coastal waters of the 

eastern North Pacific Ocean. Previous tagging studies have shown that they have the potential to 

undertake large scale migration and that there are seasonal patterns to movement. This study 

aims to investigate movement on an even finer scale. The miniaturization of pop-off satellite 

archival tags (PSATs) has enabled smaller species to be tagged. Since 2009, we have deployed 

173 PSATs on spiny dogfish at locations across the Gulf of Alaska, British Columbia (Canada), 

and Puget Sound (Washington, USA) waters. To date, 151 tags have been recovered, (6 of 

which were physical recoveries, resulting in high resolution data). As well, 6 spiny dogfish were 

double tagged with acoustic tags and deployed in Puget Sound. Data analysis is ongoing; 

however, preliminary results, such as pop-off location are already elucidating surprising 

movement patterns. Many spiny dogfish tagged in the Gulf of Alaska remained in the Gulf of 

Alaska, but a surprising number of fish moved as far south as Southern California and some 

crossed over to Russian and Japanese waters. Further, the fish that undertook the large scale 

migrations, tended to have a different daily movement pattern from those that remained. A great 

deal of analysis remains on this project, but early results are intriguing and suggest that spiny 

dogfish are more highly mobile than previously believed. 

Age and Growth Methods 

Scientists at Auke Bay Laboratory and AFSC’s Resource Ecology and Fisheries Management 

Division age and growth lab are investigating a potential new method for ageing of spiny dogfish. 

The new method, which uses the vertebrae and histological staining, has been applied to spiny 

dogfish from the U.S. East Coast in efforts to reduce the uncertainty of age estimates. The 

historical method resulted in low precision of age estimates, particularly for older fish exhibiting 

spine erosion. This prompted a search for improved methods of ageing. Spiny dogfish were aged 

by historical methods using dorsal fin spines and by a proposed new method involving vertebral 

thin sections. Centrum edge analysis confirmed an annual banding pattern on vertebrae. Ages 

were determined by multiple readers using both fin spines and vertebrae thin sections obtained 

from the same specimens. We estimated inter-reader precision and variance associated with each 

structure. The two structures yielded similar ages for younger animals, while for older animals 

age agreement depended on the quality of the thin sections. Similar to other ageing structures, 

individual variability can impact thin section quality, particularly in larger older animals. We 

were unable to fully validate vertebral thin section ages of larger, older animals because of 

variability in thin section quality and limited sample size. Each method has advantages and 

disadvantages. The dorsal fin spine method was validated previously by both oxytetracycline 

and bomb radio carbon dating, but between-reader agreement is poor. Moreover, worn or broken 

dorsal fin spines, common in older animals, require another step, where lost annuli are estimated 

through regression methods, which introduce an additional source of error into age estimation. 

In comparison, the vertebral thin section method substantially improved between-reader 

42
 
 

 

 

 

 

 

 

 

 

agreement and does not require the additional regression step, but processing of vertebrae is time 

consuming, the quality of the thin section impacts the age estimates, and validation of ages for 

larger animals has not yet been realized. In summary, the vertebrae thin section method is 

promising, but more work is required to examine individual variability in thin sections (i.e. 

quality) and ages need to be compared among the two methods from a larger sample size of 

large, old fish that have been age validated by bomb radio carbon dating. 

The second purpose of this study is to establish a method for ageing Pacific sleeper sharks. This 

new method has been successful on deep water Squaloid sharks in the North Atlantic, and there was 

some suggestion that it will work for Pacific sleeper sharks. Unfortunately, no banding patterns 

were visible on vertebrae of Pacific sleeper sharks. We are preparing to investigate other structures, 

such as the eye lens or the nueral arch. 

Population Genetics of Pacific sleeper shark 

Two species of the subgenus Somniosus are considered valid in the northern hemisphere: S. 

microcephalus, or Greenland shark, found in the North Atlantic and Arctic, and S. pacificus, or 

Pacific sleeper shark, found in the North Pacific and Bering Sea. The purpose of this study was 

to investigate the population structure of sleeper sharks in Alaskan waters. Tissue samples were 

opportunistically collected from 141 sharks from British Columbia, the Gulf of Alaska, and the 

Bering Sea. Sequences from three regions of the mitochondrial DNA, cytochrome oxidase csubunit 1 (CO1), control region (CR), and cytochrome b (cytb), were evaluated. A minimum 

spanning haplotype network separated the sleeper sharks into two divergent groups, at all three 

mtDNA regions. Percent divergence between the two North Pacific sleeper shark groups at 

CO1, cytb, and CR, respectively were all approximately 0.5 percent. Greenland sharks were 

found to diverge from the two groups by 0.6 percent and 0.8 percent at CO1, and 1.5% and 1.8 

percent at cytb. No Greenland shark data was available for CR. The consistent divergence from 

multiple sites within the mtDNA between the two groups of Pacific sleeper sharks indicates a 

historical physical separation. There appears to be no phylogeographic pattern, as both types 

were found throughout the North Pacific and Bering Sea. Development of nuclear markers 

(microsatellites) is currently underway and will allow for a better understanding of the level of 

introgression, if any, between these two ‘populations’ of sharks. 

Managing large sharks by numbers instead of weight, when observers cannot sample large fish 

The Pacific sleeper shark (Somniosus pacificus) is a common bycatch species in the Gulf of 

Alaska and Bering Sea, currently managed as part of the “Shark Complex” with harvest limits 

specified in tons. Management of the species is reliant on using estimates of total catch weight 

that are dependent on observed weight data. Sleeper sharks are difficult to handle onboard most 

vessels; they get tangled in fishing gear, their large size either precludes bringing them onboard 

or poses safety hazards to crew and observers, and they are difficult to weigh or incorporate into 

random catch sampling plans. Thus, they are uniquely challenging to manage. Conversely, 

observers are generally able to obtain accurate counts, either because the species is often presorted by vessel crew and set aside for sampling or they are tallied at the rail as gear is retrieved. 

The goal of this study is to investigate if managing by numbers would be an improvement for 

sleeper sharks. Current catch estimates show that most of the sleeper shark catches occurs in 

longline fisheries, where observed weight data is likely biased low because of the difficulty 

bringing large animals onboard. Overall, count data may provide a better estimate of total 

sleeper shark catch than currently used weight estimates. We discuss how counts could be 

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incorporated into the existing harvest specification process and associated issues with a change 

in management methods. 

Using tag data to inform biomass estimates for spiny dogfish. 

In the Gulf of Alaska (GOA) many data-poor stocks are managed using Tier 5 approach, where 

the product of the biomass and a fishing mortality rate is used to determine harvest 

specifications. This method requires that a reliable biomass is available. The biennial GOA 

trawl survey is considered “unreliable” or “at best an index of relative abundance” for this 

species, therefore the species does not qualify for Tier 5 designation. In this study we are using 

archival tag data to examine if the reliability the bottom trawl survey biomass for this species can 

be improved. The goals of this study are to 1) examine if the trawl survey overlaps with spiny 

dogfish distribution, both horizontally and vertically; 2) determine if a catchability (q) parameter 

can be estimated for the species to apply to the trawl survey biomass; and 3) investigate if the 

trawl survey biomass can be adjusted to be considered “reliable”. Temperature and depth data 

was recovered from 121 tags, where the release and/or recovery locations were in the GOA 

during the same time frame as the trawl survey. A preliminary analysis of a subset of the tags 

showed that average depth by time of day in the summer was less than 50 meters for all hours, 

with 95 percent confidence intervals ranging from the surface to 200 meters. Based on the 

tagging data and trawl survey haul data, the tagged spiny dogfish spent approximately 9 percent 

of the time within the depth range of the trawl survey gear. 

Northeast Fisheries Science Center (NEFSC) 

Biology of the White Shark (Carcharodon carcharias) 

Descriptive statistics and GIS analyses of a 210-year database were used to quantify the seasonal 

distribution and habitat use of WNA white sharks. Relative indices of abundance from historical 

NEFSC surveys and tournament data, the directed shark longline observer program, and visual 

records of white sharks in WNA were analyzed to determine temporal trends of white shark 

abundance. Study results provide an optimistic outlook for their recovery (Curtis et al. 2014). 

Age and Growth of the Bull Shark (Carcharhinus leucas) 

Age and growth of the WNA bull shark was completed using 121 vertebral samples collected 

between 1966 and 2010 (Natanson et al. 2014). Maximum age based on vertebral band pair 

counts was 25 (184 centimeters fork length (FL)) and 27 (196 centimeters FL) years for males 

and females, respectively. Based on published length at maturity estimates, males and females 

mature at 15-17 (176 - 185 centimeters FL) and 15 (189 centimeters FL) years, respectively. 

Age validation in Sand Tiger Shark, Carcharias taurus, using bomb radiocarbon analysis 

Archival vertebrae of sand tigers from both the north Atlantic and south Indian Oceans were 

processed for bomb radiocarbon analysis to validate growth band periodicity and longevity 

(Passerotti et al. 2014). Results from the WNA validated vertebral age estimates up to 12 years, 

but indicated large adult ages were underestimated by 11-12 years. Validated lifespan for 

females and males reached at least 40 and 34 years, respectively. 

Biology of the Spiny Dogfish (Squalus acanthias) 

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As part of the NEFSC spiny dogfish tagging study in the Gulf of Maine, Southern New England, 

and Georges Bank regions, 34,604 sharks were tagged and 891 were recaptured. 150 fish were 

injected with oxytetracycline (OTC) and returned for age validation through 2014. Research on 

the seasonality of pupping and gestation period continued; a year and a half of the two year 

sampling plan is complete. 

Smooth Dogfish (Mustelus canis) Movement Patterns 

Smooth dogfish mark and recapture data between 1963 and 2013, from the Cooperative Shark 

Tagging Program (CSTP) were summarized with 1134 tags and 37 recaptures (Kohler et al. 

2014). Maximum displacement distance was 460 nautical miles with distance traveled 

increasing with increasing FL. A north-south seasonal migration pattern was evident with 

movements between MA and NC. There was no movement between the Atlantic and Gulf of 

Mexico. 

Sand Tiger Movement Patterns 

NEFSC collaborative research funded by a Species of Concern grant contributed to a study using 

satellite telemetry on sand tigers in the WNA. Results showed that juveniles undergo extensive 

seasonal coastal migrations, traveling distances of approximately 2,500 kilometers over a 4-5 

month period from October to February; from as far north as northern New England south to 

central Florida before returning north the following spring (April – May) (Kneebone et al. 2014). 

Recreational Shark Fishing Data and Samples 

In 2014, biological samples and catch data for more than150 pelagic sharks from nine recreational 

fishing tournaments were added to the NEFSC historic recreational shark fishing tournament 

database. Staff also worked with multiple partners to stage an all-release, satellite tag 

tournament in NY; 2014 results included deployment of SPOT tags on two tiger sharks, three 

shortfin makos and one blue shark, as well as numerous conventional tags on shortfin makos and 

blue sharks. 

Southeast Data, Assessment, and Review (SEDAR) Process 

Staff participated in the SEDAR 39 Data Workshop for Atlantic smooth dogfish and the Gulf of 

Mexico smoothhound complex and presented multiple working papers, including: Kohler et al. 

2014, McCandless 2014a, McCandless 2014b, McCandless 2014c, McCandless and Frazier 

2014, McCandless and Greco 2014, McCandless and Gottschall 2014, McCandless and Grahn 

2014, McCandless and Mello 2014, McCandless and Olsewski 2014, McCandless et al. 2014b, 

McCandless et al 2014c, McCandless et al. 2014d. 

Endangered Species Act (ESA) 

Staff contributed to and led the Status Review Team for the WNA dusky shark. A Status Review 

Report (McCandless et al. 2014a) was provided to NMFS Protected Resources indicating that the 

WNA dusky shark was at low risk for extinction. This report was released to the public in 

December 2014 with a negative 12-month finding that listing under the ESA is unwarranted. 

Essential Fish Habitat (EFH) Designations 

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Staff provided updates to the Cooperative Atlantic States Shark Pupping and Nursery 

(COASTSPAN) and the Cooperative Shark Tagging Program (CSTP) data and results from 

ongoing research for the Stock Assessment and Fisheries Evaluation Report and the NMFS HMS 

Management Division 5-year review of EFH designations for all managed shark species, and 

provided reviews of the draft document. 

Southeast Fisheries Science Center (SEFSC) 

Observer Programs 

The shark longline observer program was created to obtain better data on catch, bycatch, and 

discards in the shark bottom longline fishery. Recent amendments to the Consolidated Atlantic 

HMS Fishery Management Plan have significantly modified the major directed shark fishery and 

implemented a shark research fishery. NMFS selects a limited number of commercial shark 

vessels (five in 2012) on an annual basis to collect life history data and catch data for future 

stock assessments. Outside the research fishery, vessels targeting shark and possessing valid 

directed shark fishing permits were randomly selected for coverage with a target coverage level 

of 4 to 6 percent. In 2014, a total of 94 trips, with a total of 126 bottom longline hauls, were 

observed. Sharks comprised 99 percent of the catch, teleosts, 0.5 percent, and batoids, 0.5 

percent. Sandbar and blacktip sharks comprised most of the shark catch. Small coastal shark 

species (e.g. Atlantic sharpnose shark) were also caught. Prohibited shark species were also 

caught, including the dusky shark, sand tiger shark, Caribbean reef shark, and white shark but in 

low numbers. Since 1993, an observer program has been underway to estimate catch and 

bycatch in the direct and indirect shark gillnet fisheries along the southeastern Atlantic coast. A 

total of 237 sets comprising various gillnet fisheries were observed in 2014. Set locations ranged 

from North Carolina to the Florida Keys in the Atlantic Ocean and the Gulf of Mexico. 

Distribution, Community Structure and Characterizing and Predicting Essential Habitat 

Features for Juvenile Coastal Sharks 

Coastal shark abundance and community structure was quantified across 10 geographic areas in 

the northeastern Gulf of Mexico using fishery-independent gillnet data from 2003 to 2011. A 

total of 3,205 sets were made in which 14,244 carcharhiniform sharks, primarily juveniles, were 

caught comprising 11 species from three families. The three most abundant species, Atlantic 

sharpnose, bonnethead, and blacktip sharks, were consistently captured over all sampling sites 

regardless of environmental conditions; however, some species (e.g., bull, blacknose, finetooth, 

and sandbar sharks) were restricted to a specific area or a range of areas. Two-way crossed 

analysis of similarity found geographic area to significantly influence shark species-life stage 

assemblages, while season did not. Resemblance matrices between environmental data and 

shark community assemblage found the two were weakly but significantly correlated, with the 

combination of salinity and water clarity producing the highest Spearman rank correlation value. 

Species diversity varied by geographic area, but was generally highest in areas with the greatest 

amount of fresh and saltwater fluctuations. Results suggest that estuarine conditions adjacent to 

river mouths may affect juvenile shark assemblages across similar latitudes and some areas of 

the northeastern Gulf of Mexico may be considered important nursery areas for select shark 

species. This study provides important insight into the habitat use of a variety of coastal shark 

species and can be used to better manage these species through the determination of critical 

habitat (Bethea et al. 2014). 

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Electronic Tagging Studies and Movement Patterns of Large Pelagic Sharks 

SEFSC scientists are using fin-mounted smart position tags (SPOT) to study the horizontal 

movement patterns of tiger (Galeocerdo cuvier), scalloped (Sphyrna lewini) and great (S. 

mokarran) hammerheads in the Gulf of Mexico (tiger, scalloped, and great hammerhead). This 

work is part of a collaborative effort with Louisiana Department of Wildlife and Fisheries and 

the University of Southern Mississippi. The information collected in this study is intended to 

address fisheries interactions and improve the management and conservation of these 

ecologically important sharks in the Gulf of Mexico. In 2014, fin-mounted SPOT tags were 

deployed on 23 sharks; 18 scalloped hammerheads, 5 tiger sharks, and 3 great hammerheads. 

Tags from 18 of the 23 sharks (15 scalloped hammerhead, 5 tiger, and 1 great hammerhead) 

reported location data with a mean reporting duration of approximately 90 days, with one tiger 

shark reporting locations over a one year. The lone reporting great hammerhead spent the 

majority of its time nearshore, while both scalloped hammerheads and tiger sharks traversed 

continental shelf and slope waters. Data are being analyzed to investigate any possible season, 

sex, and size differences in movement patterns. 

Electronic Tagging of Whale Sharks (Rhincodon typus) 

The SEFSC, in collaboration with Louisiana Department of Wildlife and Fisheries and the 

University of Southern Mississippi, has been deploying popup satellite archival tags (PSAT) and 

towable smart position tags (SPOT) for the past several years on whale sharks in the northern 

Gulf of Mexico to describe their vertical and horizontal movements. In 2014, ten PSAT and two 

SPOT tags were deployed on whale sharks during a large aggregation encounter on July 10th at 

Ewing Bank, a topographic feature off the coast of Louisiana. All PSAT tags reported data. Six 

of the tags remained on the sharks for longer than seven months and three were retained for a full 

year. The sharks spent the majority of their time in the northern Gulf of Mexico, however, 

several individuals utilized the southwest Gulf of Mexico during the fall and winter. None of the 

sharks left the Gulf of Mexico. With the addition of the 2014 tags, nearly 35 tags have been 

deployed on whale sharks in the northern Gulf of Mexico and a detailed analysis of the data is 

currently underway. 

Elasmobranch Feeding Ecology 

Studies are currently underway describing the diet and foraging ecology, habitat use, and 

predator–prey interactions of elasmobranchs. The diets of multiple shark species caught by 

commercial longline gear, including Atlantic sharpnose (Rhizoprionodon terraenovae), dusky 

(Carcharhinus obscurus), sandbar (C. plumbeus), silky (C. falciformis), and tiger (Galeocerdo 

cuvier) sharks, are currently being investigated. Along with basic diet analysis, stomach contents 

will be examined for evidence of line feeding, or depredation, on longline gear. This study will 

help to test the hypothesis that diet studies based on longline-caught animals could be biased due 

to longline depredation. Additional data are being collected during SEFSC bottom longline 

surveys to examine spatial variability in the diets and feeding behaviors of various shark species. 

Cooperative Gulf of Mexico States Shark Pupping and Nursery Survey (GULFSPAN) and 

Tagging Database 

The SEFSC Shark Population Assessment Group manages and coordinates a survey of coastal 

bays and estuaries from Florida to Louisiana. Surveys identify the presence or absence of 

neonate (newborn) and juvenile sharks and attempt to quantify the relative importance of each 

47
 
 

 

 

 

 

 

 

 

 

 

 

area as it pertains to essential fish habitat. A database currently includes over 10,000 tagged 

animals and 205 recaptured animals from 1993 to the present for both the Gulf of Mexico and 

U.S. southeast Atlantic Ocean. This fully searchable database is current through spring 2010 

with hopes to have it online in 2016. 

Monitoring the Recovery of Smalltooth Sawfish (Pristis pectinata) 

The smalltooth sawfish was the first marine fish listed as endangered under the Endangered 

Species Act (ESA). Smalltooth sawfish has been listed under the ESA since 2005, and the 

completion of the Smalltooth Sawfish Recovery Plan in early 2009 identified new research and 

monitoring priorities that are currently being implemented. Surveys identify the presence or 

absence of neonates, young-of-the-year, and juveniles in southwest Florida and research in the 

Florida Keys and Florida examines the distribution and abundance of adult animals. 

Life History Studies of Elasmobranchs 

In collaboration with Florida State University, scientists are examining age, growth, and 

reproduction of Cuban dogfish. In addition, research is also being conducted with the Bimini 

Biological Station on the life history of the lemon shark. Studies on the life history of Atlantic 

blacktip shark, finetooth, blacknose shark, smoothhound sharks, and various species of 

deepwater sharks, including gulper and lantern sharks continued in 2014. 

Cooperative Research: Uruguay–U.S. Pelagic Shark Research Project 

An ongoing collaborative project with Uruguay’s fisheries agency (DINARA) aims to advance 

knowledge on movement patterns, habitat use, and susceptibility of pelagic sharks to longline 

fisheries in the western South Atlantic. By the end of 2014, twelve satellite tags had been 

deployed on blue sharks to date, and five tags were providing real time data, which, along with 

data for Ecological Risk Assessments, are used as outreach to promote the collaboration between 

NOAA and DINARA. 

Shark Assessment Research Surveys 

The SEFSC has conducted annual bottom longline surveys in the northern Gulf of Mexico and 

off the east coast of the United States since 1995 (31 surveys have been completed through 

2014). The primary objective is to utilize standardized gear to assess the distribution and 

abundance of large and small coastal sharks across their known ranges to provide fisheriesindependent time series data for trend analysis. The survey is the largest of its kind and is 

considered essential for accurate stock assessments of sharks occurring off the East Coast of the 

United States and throughout the northern Gulf of Mexico. This survey also provides a platform 

for other shark research activities including identification of essential habitats, reproductive 

biology, feeding behavior, gear selectivity, movement patterns, and effects of deleterious 

anthropogenic impacts. To date, over 38,000 fishes have been collected during the survey of 

which approximately 85 percent were sharks. 

4.2 Incidental Catch Reduction 

Pacific Islands Fisheries Science Center (PIFSC) 

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Redistribution of longline hooks to reduce shark bycatch – The interspecific preferences of 

fishes for different depths and habitats suggest fishers could avoid unwanted catches of some 

species while still effectively targeting other species. In pelagic longline fisheries, albacore 

(Thunnus alalunga) are often caught in relatively cooler, deeper water ( greater than100 meters) 

than many species of conservation concern (e.g., sea turtles, billfishes, and some sharks) that are 

caught in shallower water ( less than 100 meters). From 2007 to 2011, this study examined the 

depth distributions of hooks for 1154 longline sets, a total of 3,406,946 hooks, and recorded 

captures by hook position on 2642 sets, a total of 7,829,498 hooks, in the American Samoa 

longline fishery (Watson and Bigelow, 2014). 23 percent of hooks had a settled depth less than 

100 meters. Individuals captured in the three shallowest hook positions accounted for 18.3 

percent of all bycatch. The study analyzed hypothetical impacts for 25 of the most abundant 

species caught in the fishery by eliminating the three shallowest hook positions under scenarios 

with and without redistribution of these hooks to deeper depths. Distributions varied by species: 

45.5 percent (of a sample size of 10 individuals) of green sea turtle (Chelonia mydas), 59.5 

percent (of a sample size of 626 individuals) of shortbill spearfish (Tetrapturus angustirostris), 

37.3 percent (of a sample size of 435 individuals) of silky shark (Carcharhinus falciformis), and 

42.6 percent (of a sample size of 150 individuals) of oceanic whitetip shark (C. longimanus) 

were caught on the three shallowest hooks. Eleven percent (of a sample size of 20,435 

individuals) of all tuna and 8.5 percent (of a sample size of 10,374 individuals) of albacore were 

caught on the three shallowest hooks. Hook elimination reduced landed value by 1.6–9.2 percent 

and redistribution of hooks increased average annual landed value relative to the status quo by 5– 

11.7 percent. Based on these scenarios, redistribution of hooks to deeper depths may provide an 

economically feasible modification to longline gear that could substantially reduce bycatch for a 

suite of vulnerable species. The results suggest that this method may be applicable to deep-set 

pelagic longline fisheries worldwide (Watson and Bigelow, 2014). 

Using net illumination to reduce elsamobranch bycatch. 

PIFSC has been involved in the development of shark bycatch reduction technologies for other 

fisheries, in particular, coastal gillnet fisheries. Net illumination through the use of LED lights 

have been tested in small scale coastal gillnet fishery 

based in Baja California, MX. Experiments using short 

wavelength (UV range), mid length (green wavelengths) 

and long wavelengths (orange/red) have been conducted 

to understand the effects on catch composition. 

Analysis of results show that UV illumination of gillnets 

significantly reduces the catch rates of elasmobranchs, 

in particular guitarfish and scalloped hammerhead 

sharks (S. lewini). In addition, experiments with orange 

(605 nautical miles wavelength) net illumination suggest 

that elasmobranch interaction rates can also be reduced. 

Both types of net illumination do not affect the target 

catch rates or significantly change the market value. 

This suggests that net illumination may be a useful 

strategy to reduce shark interactions in coastal gillnet 

fisheries. 

Southwest Fisheries Science Center (SWFSC) 

Figure 4.2.1: Orange LEDs attached 

to experimental gillnet. 

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Testing Deep-set Longline Gear 

In the California pelagic drift gillnet fishery that targets swordfish, blue sharks have historically 

been one of the main bycatch species. The majority (approximately 63 percent) of the blue 

sharks entangled are discarded dead. To reduce the bycatch and/or post-release mortality of 

multiple species, the SWFSC has been conducting tests since 2011 to target swordfish using 

deep-set longline gear (DSLL) off California at depths below 200 meters. These deeper depths 

coincide with the daytime distribution of swordfish, putting hooks below the epipelagic waters 

inhabited by sea turtles and many mako sharks. On four cruises from 2011-2014, SWFSC 

collaborated with longline fishers aboard the chartered F/V Ventura II off central and southern 

California to target swordfish during the day. Over all four cruises and 54 sets, a total of 149 

marketable fish were landed (including 9 swordfish, 97 opah, and 31 Pomfret). Of the 449 nonmarketable fish caught, 417 were blue sharks. A deep-set longline fishery off southern and 

central California would likely be a mixed fishery including some tunas and opah in their 

marketable catch. This study concluded that it is possible to catch swordfish and other 

marketable species below turtle and shortfin mako habitat with a DSLL however, swordfish 

catch was low and blue shark catch was high. Fishing conditions during these cruises were 

probably impacted by anomalous oceanographic conditions; swordfish catch for the drift gillnet 

fleet was very low over the same time periods. Given the experimental and small-scale nature of 

this research, these results are promising, but should not be projected beyond the study and 

warrant more research. Additional efforts by commercial fisheries with fewer constraints on the 

timing and location of fishing are needed to truly assess the potential for this fishery. 

West Coast Region (WCR) and PIER Testing Swordfish Deep-set Buoy Gear 

The Pfleger Institute of Environmental Research (PIER), in collaboration with NMFS WCR, is 

conducting research into use of novel deep-set buoy gear (DSBG) to test the efficacy of 

capturing swordfish at depth (300 meters and deeper) during the day while avoiding both 

unwanted finfish bycatch (including blue sharks) and bycatch of species of concern. As with the 

deep-set longline research being conducted by the SWFSC, targeting deeper depths coincides 

with known day time habitat preference of swordfish and puts hooks below the upper water 

column habitat preferred by leatherback turtles and several shark species. A description of the 

development of DSBG and initial gear experiments was published in early 2015 (Sepulveda et 

al., 2015). DSBG trials performed in 2014 focused on assessing catch and non-target catch rates 

and assessing potential market dynamics. DSBG deployments from research and cooperative 

vessels resulted in the capture of over 90 swordfish in 2014. The collective marketable catch 

rate was over 94 percent suggesting high selectivity and very low catch of blue sharks. Per 

vessel catch rates ranged from 0.6 to 1.70 fish per 8 hour soak period. Initial market analyses 

revealed DSBG swordfish price-point to be similar to harpoon caught product and nearly double 

that of the existing net fishery. In 2015 the team has petitioned the Pacific Council for exempted 

status in an attempt to move the DSBG experiment towards future implementation off the U.S. 

West Coast. 

4.3 Post-Release Survival 

Southwest Fisheries Science Center (SWFSC) 

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Common thresher, shortfin mako, and blue sharks are captured in both commercial and 

recreational fisheries in the California Current. The California drift gillnet fishery is the 

commercial fishery that catches the greatest number of each of these species. While thresher and 

mako sharks are landed, almost all blue sharks are discarded. For thresher and mako sharks, 

regional recreational fisheries are growing in popularity. Recreational fishermen are often 

interested only in the challenge of the fight and will frequently release their catch. The survival 

rate of sharks released both from the California drift gillnet fishery and by recreational anglers is 

unknown. Reliable estimates of mortality are necessary in order to adequately assess the status 

of the stocks and determine the effects of the fisheries on their abundance. 

Thresher Sharks Released from the Recreational Fishery 

Researchers from the SWFSC, WCR, and PIER have completed a three-phase study to assess the 

post-release survival of thresher sharks caught by recreational anglers. The first phase of the 

study, which was published in 2010, involved releasing sharks which had been captured using 

tail-hooking techniques, which are common practice in the southern California fishery. The 

results from this work revealed that survivorship is low for large sharks (greater than 185 

centimeters FL) that endure fight times that exceed 85 minutes (Heberer et al., 2010). The 

second and third phases of the research effort were analyzed and submitted to Fisheries Research 

in 2014 and published in early 2015 (Sepulveda et al. 2015). The study compared the 

survivorship of sharks that are tail-hooked but break away, trailing the tackle, including a one 

pound trolling lure commonly used when angling for sharks, with the survivorship of sharks 

caught by mouth hooking. For the trailing gear investigation the overall survivorship rate was 22 

percent. It is likely that the trailing weight interfered with movement and/or feeding. For the 

mouth-based trials, all common thresher sharks survived the acute effects of capture (100 percent 

survivorship). Overall, the results from all phases of this study indicate that methods which 

maximize mouth-based capture and reduced fight times should be adopted as best fishing 

practices by the fishery to reduce the mortality of released thresher sharks. 

Blue Sharks Released from the Experimental Deep-set Longline Gear 

Given the large numbers of blue sharks caught during the deep-set longline experiment and 

concerns about associated mortality, a second objective of the deep-set longline 2014 cruise was 

to conduct a study of the post-release mortality of blue sharks. This study included the 

measurement of a number of previously established condition factors (i.e. eye reflex, body 

movements), measures of blood lactate, and the use of satellite tags to actually document 

mortality. Lactate levels were measured in 47 sharks, 15 satellite tags were deployed and 

condition factors were determined for 85 individuals. The condition factors most closely linked 

to higher lactate levels had to do with full body movements, sharks that were moving had lower 

lactic acid levels. Of the 14 tags that reported, 4 tags indicated that the sharks had died within a 

day of release. The 4 mortalities had the 4 lowest condition scores and 4 of the 5 highest lactate 

levels. Soak time was not a factor. While additional work is needed, these results show promise 

for estimating post-release mortality based on a condition factor and blood lactate levels. 

Northeast Fisheries Science Center (NEFSC) 

Post-release Recovery and Survivorship Studies in Sharks: Physiological Effects of Capture 

Stress 

51
 
 

 

This ongoing cooperative research is directed toward coastal and pelagic shark species caught on 

recreational and commercial fishing gear. This work is collaborative with researchers from 

Massachusetts Division of Marine Fisheries (MDMF) and many other state and academic 

institutions. These studies use blood and muscle sampling methods, including hematocrit, 

plasma ion levels, and red blood cell counts, coupled with acoustic tracking and pop-up satellite 

archival tags (PSAT) data to quantify the magnitude and impacts of capture stress. The primary 

objectives of the new technology tag studies are to examine shark migratory routes, potential 

nursery areas, swimming behavior, and environmental associations. Secondarily, these studies 

can assess the physiological effects of capture stress and post-release recovery in commerciallyand recreationally-captured sharks. These electronic tagging studies include: 1) acoustic tagging 

and bottom monitoring studies for coastal shark species in Delaware Bay and the USVI as part of 

COASTSPAN; 2) tracking of porbeagle sharks with acoustic and PSATs in conjunction with the 

MDMF; 3) placing real-time satellite (SPOT) and PSAT tags on shortfin makos and blue sharks 

in the Northeast U.S. and on their pelagic nursery grounds; 4) placing PSAT tags on sand tigers in 

Delaware Bay and Plymouth Bay (MA) as part of a fishery independent survey and habitat study; 

and 5) placing PSAT and SPOT tags on dusky and tiger sharks in conjunction with Monterey 

Bay Aquarium, University of California Long Beach, and MDMF. Integration of data from newtechnology tags and conventional tags from the CSTP is necessary to provide a comprehensive 

picture of the movements and migrations of sharks along with possible reasons for the use of 

particular migratory routes, swimming behavior, and environmental associations. In addition, 

the results of this research will be critical to evaluate the extensive current catch-and-release 

management strategies for sharks. 

Southeast Fisheries Science Center (SEFSC) 

Determination of Alternate Fishing Practices to Reduce Mortality of Prohibited Dusky Shark 

in Commercial Longline Fisheries 

SEFSC continues to conduct a series of fishing experiments using commercial fishing vessels 

participating in the Shark Research Fishery to investigate methods to reduce at-vessel mortality 

of dusky shark, a prohibited species. Pop-off archival satellite tags have also been deployed on 

select individuals to aid in determining the efficacy of closed areas for dusky shark. Preliminary 

logistic modeling analysis indicates median mortality occurs after 6.6 hours of being hooked, and 

13.5 hours of soak time. Water temperature was not a significant factor in analysis. The 

difference in the mortality rates of hooking time versus soak time suggest that soak time is longer 

than the tolerance of dusky sharks to longline fishing. These preliminary results reflect the 

potential of bycatch mortality rates to influence already depleted populations, and these results 

could be used to propose regulations on longline soak time that could aid in population recovery 

of this species 

Hooking mortality of scalloped hammerhead, Sphyrna lewini, and great hammerhead, 

Sphyrna mokarran, sharks caught on bottom longlines 

The scalloped hammerhead and the great hammerhead are typically caught as bycatch in a 

variety of fisheries and are listed as globally Endangered by the International Union for the 

Conservation of Nature. Due to very high at-vessel mortality for these species, research is 

needed on fishing methods to reduce mortality for longline-captured sharks. A series of fishing 

experiments were conducted employing hook timers and temperature–depth recorders on 

52
 
 

 

 

 

 

 

 

 

contracted commercial vessels fishing with bottom-longline gear to assess factors related to 

mortality. A total of 273 sets were deployed with fifty-four 485 hook timers. Scalloped and 

great hammerheads had at-vessel mortality rates of 62.9 percent and 56.0 percent, respectively. 

Median hooking times for scalloped and great hammerheads were 3.5 h and 3.4 h, respectively, 

and 50 percent mortality was predicted at 3.5 hours and 3.8 hours. When these data are 

considered for potential management strategies to reduce the mortality of hammerhead sharks, a 

limitation on gear soak time would probably improve hammerhead shark survivorship. 

However, it may prove to be difficult for a fishery to remain economically viable if the soak time 

is limited to less than the median hooking time for the target species. Additional management 

options, such as time/area closures, may need to be explored to reduce bycatch mortality of 

scalloped and great hammerheads. Results of this research were presented at the Sharks 

International 2014 conference, held 2–6 June 2014, in Durban, South Africa, and are part of a 

special issue on ‘Advances in Shark Research’ in the African Journal of Marine Science. 

The effect of circle hooks on shark catchability, at-vessel mortality and post-release survival 

rates in bottom longline fisheries 

Over the last few years, a growing number of studies have investigated the use of circle hooks 

and their effects on a range of species, including sharks. However, for sharks, managers and 

scientists are confronted with multiple studies of small sample sizes with either conflicting 

results or no statistical significance and no clear conclusions. Controlled experiments are being 

conducted comparing catchability, at-vessel mortality, and post-release survivorship in longline 

sets using J style hooks and those using circle hooks. A contracted fishing vessel is deploying 

300 hooks per set and with the exception of hook type, all other factors remain constant. Soak 

time is limited to the average rate observed for the fishery. All gangions are two m long and 

constructed of a snap, 363 kilogram test monofilament line and a swivel, to which the leader and 

hook are attached. The two experimental treatments are Lindgren-Pitman Inc. 0° offset 18/0 

circle hooks and Mustad 12/0 J hooks. Post-release survivorship will be assessed tagging 

sandbar sharks with a satellite pop-up archival transmitting (PAT) tag. Survival of post-captured 

PAT tagged animals (of a sample size of 20 individuals) will be inferred from data provided by 

the PAT tag. Data from six tags has been analyzed and preliminary results suggest that two 

animals suffered mortality, one tag pulled, and three animals survived. Overall, preliminary 

results find no significant differences between hook types in catch rates, little or no significant 

differences in at-vessel mortality, and no significant differences in post-release mortality by hook 

type. However, post-release mortality may be higher than expected. 

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Section 5: Additional 

Information About Ongoing 

NOAA Shark Research 

Alaska Fisheries Science Center (AFSC, Auke Bay Laboratory) 

The AFSC conducts a variety of surveys which provide data for the stock assessments. In the 

Gulf of Alaska (GOA) there is a biennial trawl and annual longline survey. The trawl survey 

provides an estimate of biomass for spiny dogfish and the longline survey provide a relative 

index of abundance for spiny dogfish and Pacific sleeper sharks. The trawl surveys in the Bering 

Sea/Aleutian Islands (BSAI) do not sample sharks well and are not used in the stock assessment. 

The International Pacific Halibut Commission also conducts an annual longline survey in the 

GOA and BSAI, which samples a large number of stations each year and provides a relative 

index of abundance for both spiny dogfish and Pacific sleeper shark. The IPHC survey likely 

provides the most informative index because it samples both species of sharks across the full 

range of the survey and regularly at most of the stations. 

Stock assessment and research efforts at the Alaska Fisheries Science Center’s Auke Bay 

Laboratory (not described above) are focused on: 

•	 Improving stock assessments and collection of data to support stock assessments of shark 

species subject to incidental harvest in waters off Alaska. 

•	 Migration and habitat use of Pacific sleeper sharks. 

•	 Migration and habitat use of spiny dogfish. 

•	 Development and validation of improved ageing methods for spiny dogfish and Pacific 

sleeper sharks. 

•	 Investigations into life history characteristics and population demography. 

•	 Examining the effect of observer coverage on catch estimates. 

Stock Assessments of Shark Species Subject to Incidental Harvest in Alaskan Waters 

Species currently assessed in Alaskan waters include Pacific sleeper sharks (Somniosus 

pacificus), spiny dogfish (Squalus suckleyi, note that this was formerly referred to as S. 

acanthias; see Ebert et al. 2010 for details of the species description), and salmon sharks (Lamna 

ditropis). These are the shark species most commonly encountered as incidental catch in 

Alaskan waters. In both the Gulf of Alaska (GOA) and Bering Sea/Aleutian Islands (BSAI) 

fishery management plans, sharks are managed as a complex. There are no directed fisheries for 

sharks in either area and directed fishing for all sharks is prohibited. Most shark species are 

considered Tier 6, where annual catch limits are based on estimated historical incidental catch in 

the groundfish fisheries. In the GOA, spiny dogfish is currently Tier 5, with annual catch limits 

54
 
 

 

 

 

 

 

based on biomass and natural mortality. Biomass is currently estimated from the NMFS fisheryindependent bottom trawl survey; however, it is thought that other surveys may better reflect the 

populations. Efforts are underway to develop a model to estimate biomass for spiny dogfish that 

would include data such as the NMFS and International Pacific Halibut Commission annual 

longline surveys. Stock assessments are summarized annually in the North Pacific Fishery 

Management Council’s Stock Assessment and Fishery Evaluation Report (see Tribuzio et al. 

2013a and 2013b). 

Trophic Ecology of Pacific Sleeper Sharks in the Eastern North Pacific Ocean 

Stable isotope ratios of nitrogen (reported in δ15N) and lipid normalized carbon (reported in δ 

13C’) were used to examine geographic and ontogenetic variability in the trophic ecology of 

Pacific sleeper sharks in the eastern North Pacific Ocean (Courtney and Foy 2012). Mean 

muscle tissue δ 13C’ values of Pacific sleeper sharks differed significantly among geographic 

regions of the eastern North Pacific. Linear models identified significant ontogenetic and 

geographic variability in muscle tissue δ 15N values. The trophic position of Pacific sleeper 

sharks in the eastern North Pacific, estimated from previously published stomach content data, 

was within the range of Pacific sleeper shark trophic position predicted from a linear model of 

muscle tissue δ 15N (3.3–5.7) for sharks of the same mean total length (LT; 201.5 centimeters). 

However, uncertainty in predicted trophic position was very high (95 percent prediction intervals 

ranged from 2.9–6.4). The relative trophic position of Pacific sleeper sharks determined from a 

literature review of δ 15N by taxa in the eastern North Pacific was lower than would be expected 

based on stomach content data alone when compared to fish, squid, and filter feeding whales. 

Stable isotope analysis revealed wider variability in the feeding ecology of Pacific sleeper sharks 

in the eastern North Pacific than shown by diet data alone, and expanded previous conclusions 

drawn from analyses of stomach content data to regional and temporal scales meaningful for 

fisheries management. 

Migration and Habitat Use of Pacific Sleeper Sharks 

During the summers of 2003–2006, scientists from Auke Bay Laboratory deployed 138 

numerical Floy tags, 91 electronic archival tags, 24 electronic acoustic tags, and 17 electronic 

satellite popup tags on Pacific sleeper sharks in the upper Chatham Strait region of Southeast 

Alaska (Courtney and Hulbert 2007). Two numerical tags and ten satellite tags have been 

recovered. The recovery of temperature, depth, and movement data from the electronic archival 

and acoustic tags will aid in the identification of Pacific sleeper shark habitat utilization and 

distribution in Southeast Alaska, and identify the potential for interactions between Pacific 

sleeper sharks and other species in this region. Analysis of tagging data is ongoing. 

Reproduction in salmon shark 

Little is known about the reproductive biology of the salmon shark, Lamna ditropis, from the 

eastern North Pacific Ocean. Female salmon shark specimens were collected from Alaska 

waters in the summer, autumn, and winter to examine reproductive timing, periodicity, and 

fecundity. Results suggest that female salmon sharks ovulate during the autumn months of 

September and October. Further, those animals captured in July were either in a resting or postpartum state indicating a short gestation time of nine to ten months. The presence of two 

maturity stages in both the summer and autumn months indicates a resting period of at least 14 

months between parturition and ovulation. This study found mean fecundity was 3.88 (n = 8, SE 

55
 
 

 

 

 

 

 

= 0.13) with the majority of pregnant salmon sharks having a fecundity of four sharks per litter. 

These results provide new information on the reproductive biology of salmon sharks and will aid 

in the development of stock assessments for this species. 

Northwest Fisheries Science Center (NWFSC) 

Monitoring and Assessment Activities 

The NWFSC conducts and supports several activities addressing the monitoring and assessment 

of sharks along the West Coast of the United States and in Puget Sound. The PacFIN serves as a 

clearinghouse for commercial landings data, including sharks. In addition, the At-Sea Hake and 

West Coast Groundfish Observer Programs collect data on shark species caught on vessels 

selected for observer coverage. 

The NWFSC conducts annual trawl surveys of the West Coast, designed primarily to acquire 

abundance data for West Coast groundfish stocks. The tonnages of all shark species collected 

during these surveys are documented. In addition, the survey program has conducted numerous 

special projects in recent years to help researchers acquire data and samples necessary for 

research on various shark species. 

In addition to these monitoring activities, the NWFSC conducted the first assessment for 

longnose skate in 2007. This assessment was reviewed during the 2007 stock assessment review 

(STAR) process, and was adopted by the PFMC for use in management. The NWFSC last 

conducted an assessment of spiny dogfish along the Pacific coast of the United States in 2011 

(see section 2.3 of the 2014 Shark Finning Report to Congress). 

Southwest Fisheries Science Center (SWFSC) 

Shark research 

The NOAA Fisheries Southwest Fisheries Science Center (SWFSC) shark research program 

focuses on pelagic sharks that occur along the U.S. Pacific Coast, including blue sharks 

(Prionace glauca), basking sharks (Cetorhinus maximus), shortfin mako (Isurus oxyrinchus), and 

three species of thresher sharks: bigeye, common, and pelagic threshers (Alopias superciliosus, 

A. vulpinus, and A. pelagicus, respectively). Center scientists are studying the sharks’ biology, 

distribution, movements, stock structure, population status, and potential vulnerability to fishing 

pressure. This information is provided to international, national, and regional fisheries 

conservation and management bodies having stewardship for sharks. In addition to the work 

discussed above, the sections below describe other research also being carried out at the center. 

Electronic tagging data analyses 

Since 2004, scientists at the SWFSC have been opportunistically tagging common thresher 

sharks with electronic tags during the annual shark surveys. To date twenty-nine common 

thresher sharks have been tagged with either PSAT3, SPOT4, or both. Of the 27 PSAT3 tags 

released, four were recovered and 16 transmitted data. Of the SPOT4 tags deployed, all failed to 

report, despite confirmation of survivorship from paired PSAT tags, showing that this technology 

is not useful tags for tracking common thresher sharks. Tagged threshers ranged in size from 89­

200 centimeters fork length, 127 ± 30 centimeters (mean ± SD), with the majority under the 

56
 
 

 

 

 

 

 

estimated size at maturity (160 centimeters) for this species (Smith et al. 2008). Preliminary 

analyses indicate that threshers spend much more time near the surface in the mixed layer than 

they do at greater depths, and that vertical excursions below the mixed layer primarily occur 

during the day (Figure 2), potentially due to their unique hunting strategy which relies on visual 

prey detection. Data from stomach contents and coastal pelagic prey densities are being 

analyzed to further investigate their movements relative to their preferred prey. 

Figure 5.1. Swimming depth histogram of tagged common thresher sharks during night 

(black bars) and day (white bars). Depth bins are labeled by the upper bounds of the bin, 

i.e. 10 indicates 0-10 meters. 

The horizontal movements of these animals are harder to characterize than vertical movements, 

because the light-based geolocation estimates determined from PSATs are less accurate than the 

locations from the SPOT tags. Despite this difficulty, data from tags are being analyzed using a 

Bayesian approach and then integrated with commercial catch data to improve our understanding 

of the long distance horizontal movements of threshers. A manuscript on the movement of 

thresher sharks is currently being drafted. 

Basking shark electronic tag data analyses 

The SWFSC has an ongoing basking shark research program. During 2014, data from four 

sharks tagged with satellite tags in 2010 and 2011 were analyzed and the results prepared for 

publication. The four sharks showed impressive plasticity in geographic movements and vertical 

behaviors depending upon the region and distance from shore, as has been shown in the Atlantic. 

Of the two tracks that progressed into winter months, one shark went south along the Baja 

Peninsula while the other shark moved southwest to waters just north of Hawaii (Figure 3). A 

comparison of vertical movements with acoustic back-scatter data in the Central Pacific reveals 

that basking sharks track a consistent scattering layer as they move between 450-470 meters 

during the day and 250-300 meters at night. Scatter data reveal the presence of small crustaceans 

57
 
 

 

 

 

 

and gelatinous zooplankton in this layer. The potential presence of smaller prey such as 

copepods cannot be resolved with the frequencies used in this study. Interestingly, basking 

sharks appear to leave daytime depths a few hours prior to sunset which is uncommon for most 

deep scattering layer (DSL) predators but has been observed in copepods. This suggests that 

copepods may still be important prey offshore, as they are in nearshore waters, however 

additional data are still needed. 

Figure 5.2. (Top) The track of a basking shark tagged on 6/7/2011 off San Diego. The tag 

released as programmed on 2/2/2012. (Bottom) The track of a basking shark tagged on 

8/2/2011 off Monterey. The tag released as programmed on 1/29/2012. Green circles 

indicate tagging location; red triangles are pop off locations. 

Population Genetics Studies 

Continuing work on shortfin mako genetics has provided new insight into possible sex-biased 

gene flow. Earlier work using mitochondrial control region DNA sequences detected population 

heterogeneity between the north and south Pacific as well as between the southeast and 

southwest Pacific. Unlike the mitochondrial data, recently completed nuclear microsatellite 

studies have yielded no significant signals for population heterogeneity. As mitochondrial DNA 

is inherited maternally this suggests that there is a degree of female philopatry to nursery 

grounds in these separate regions. The lack of heterogeneity using the nuclear markers suggests 

that there is sufficient male-mediated geneflow among these regions to genetically homogenize 

populations. 

Foraging Ecology of Pelagic Sharks 

The California Current is a productive eastern boundary current that is an important nursery and 

foraging ground for a number of highly migratory predator species. To better understand niche 

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separation and the ecological role of spatially overlapping species, SWFSC researchers have 

been analyzing the stomach contents of pelagic sharks since 1999. Stomachs are obtained 

primarily from the CADGN observer program. 

Stomach content Analysis 

Stomach content analysis of blue, shortfin mako and thresher sharks is ongoing. Interannual 

variation provides insight into the relative abundance of mid trophic level prey. The stomachs of 

several species of pelagic sharks caught during the 2013 fishing season were analyzed in 2014. 

For the 2013 season, shortfin mako stomachs (n=54) contained Pacific saury (F=28; 

F=Frequency of prey occurrence), market squid (F=9), paper nautilus (Argonauta sp.) and 

Gonatus spp. squid (F=5). Jumbo squid (Dosidicus gigas) was found only in one stomach in 

contrast to prior seasons when it was dominant. Blue shark stomachs (n=5) contained Gonatus 

spp. squid (F=5), octopus squid (F=5), and Histioteuthis spp. (n=3). Common prey in thresher 

shark stomachs (n=16) was market squid (F=5) and Pacific saury (F=2). 

Stable isotope analysis of Pelagic Sharks, Swordfish and their prey 

In addition to the ongoing analysis of stomach contents, researchers at the SWFSC have been 

collecting stable isotope samples from highly migratory predators, as well as prey found in their 

stomachs. Collected tissue samples are being analyzed for both δ14C and δ15N in order to further 

our understanding of the trophic ecology of these mobile species across a wider time frame then 

stomach content analysis alone can provide. So far, 90 predator muscle samples and 86 prey 

samples have been processed and results are currently being compiled. 

Blue and Thresher Shark Spiral Valve Parasite Analysis 

The basic principle underlying the use of parasites as tags in shark population studies is that 

sharks may become infected with a parasite only when they come within the endemic area of that 

parasite. The endemic area is the geographical region in which conditions are suitable for the 

transmission of the parasite (MacKenzie and Abaunza 1998). In addition, different parasites can 

be associated with different prey. 

A preliminary study on the spiral valve parasite content of blue and thresher sharks was started in 

2011. These species co-occur along the U.S. and Mexico West Coasts during certain times of 

the year. While they are both caught in the CADGN fishery, a prior study showed that their diet 

and ecological differ (Preti et al. 2012). The contents of 20 blue and 20 thresher shark spiral 

valves were analyzed for parasite loads in order to determine if there are differences in parasite 

loads between these two shark species, and how parasites are associated with different prey and 

the areas where these predators forage. Preliminary results show that blue and thresher sharks 

have different parasites in their spiral valves suggesting that the two predator species spend time 

in different areas and/or eat different prey (Table 5.1). 

Table 5.1 Parasites found in the spiral valves of blue and thresher sharks. 

Parasite species Host Parasite Class 

Prosobothrium armigerum Blue Cestoda 

Anthobothrium laciniatum Blue Cestoda 

Paraorygmatobothrium prionacis Blue Cestoda 

Platybothrium auriculatum Blue Cestoda 

59
 
 

 

 

 

 

 

 

 

 

Unid. Phyllobothriid Blue Cestoda 

Gymnorhynchus sp. Blue / Thresher Cestoda 

Acanthocelius sp. Blue 

Cestode fragments Blue 

Gymnorhynchus sp. Blue 

Paraorygmatobothrium exiguum Thresher Cestoda 

Lacistorhynchus tenuis Thresher Cestoda 

Anisakis sp. larvae Thresher Nematoda 

Hysterothylacium incurvum Thresher Nematoda 

Piscicapillaria sp. Thresher Spirurid Nematod 

Rhadinorhynchus cololabis Thresher Acanthocephala 

Pennella remains Thresher Subclass (Copepoda) 

Blue Sharks Released from the California Drift Gillnet Fishery (CADGN) 

The CADGN fishery targets swordfish in the California Current. With the exception of ocean 

sunfish, blue sharks have historically been caught in greater numbers than any other fish species 

taken in this fishery. Nearly all blue sharks are discarded at sea due to lack of market value. A 

2009 analysis of the 1990-2008 observer data reveals that 32percent of blue sharks captured were 

released alive. In 2007, researchers from the SWFSC and the WCR began deploying PSAT tags 

on sharks released from the CADGN fishery to assess survivorship in order to determine more 

accurate estimates of fishery removals for use in a blue shark stock assessment. As part of the 

study, a set of criteria was developed to document the condition of all live blue sharks released: 

“good,” “fair,” or “poor”. 

Prior to the 2013-2014 season, 15 blue sharks (100 to 200 centimeters FL) had been tagged by 

fishery observers. Three of the 15 sharks were released in “good” condition; ten were released in 

“fair” condition; and two in “poor” condition. The two sharks that were released in “poor” 

condition as well as one released in “fair” condition did not survive the acute effects of capture 

in the CADGN fishery. These results, suggest that sharks that are released in “good” condition 

are likely to survive, whereas those released in “poor” condition are likely to die. However, the 

number of tagged sharks is low and we hope to tag three more sharks in “poor” condition in 

order to strengthen the findings. In general, when sharks are brought to the vessel alive, most are 

in “good” or “fair” condition. No tags have been released during the past two seasons due to low 

effort and few “poor” condition candidate blue sharks caught, but SWFSC scientists hope to 

complete the study during the 2015-2016 season. 

Pacific Islands Fisheries Science Center (PIFSC) 

Age Validation using Bomb Radiocarbon Dating 

PIFSC scientists in collaboration with Northeast Fisheries Science Center led a recent study to 

validate age estimates for the sandbar shark (Carcharhinus plumbeus), a cosmopolitan species of 

subtropical and tropical seas. The sandbar shark was the cornerstone species of western North 

Atlantic and Gulf of Mexico coastal bottom longline fisheries until 2008, when they were 

60
 
 

 

 

allocated to a research-only fishery. Despite decades of fishing on this species, important life 

history parameters, such as age and growth, have not been well known. Results from both tagrecapture data and bomb radiocarbon dating show longevity to exceed 30 years for this species 

(Andrews et al., 2011). The findings of this study indicated there was missing time in the growth 

structure of the vertebrae for this species, leading to an underestimation of longevity by more 

than ten years. 

Fishery Data Collection 

Market data from the PIFSC shoreside sampling program contain detailed biological and 

economic information on sharks in the Hawaii-based longline fishery dating from 1987. These 

data are primarily collected from fish dealers who are required to submit sales/transaction data to 

the State of Hawaii. The Western Pacific Fishery Information Network (WPacFIN) is a Federal– 

State partnership collecting, processing, analyzing, and sharing, fisheries data on sharks and 

other species from U.S. island territories and states in the Central and Western Pacific(Hamm et 

al. 2011). The WPacFIN program has assisted other U.S. islands’ fisheries agencies in American 

Samoa, Guam, and the Commonwealth of the Northern Mariana Islands in modifying their datacollection procedures to include bycatch information. These modifications have improved the 

documentation of shark interactions with fishing gear. Shark catches in the Hawaii-based 

longline fishery have been monitored by a logbook program since 1990 and by an observer 

program since 1994. American Samoa has had a federal logbook program since 1996, and an 

observer program since 2006. 

Biometrics Research on Catch Statistics 

Biometrics research on shark longline bycatch issues funded by the Pelagic Fisheries Research 

Program (University of Hawaii) was documented in Walsh et al. (2009). This work was based 

on analyses of shark catch data from the Pacific Islands Regional Office (PIRO) Observer 

Program. The results included a detailed description of the taxonomic composition of the shark 

catch, as well as additional information pertinent to either the management (e.g., nominal catch 

rates, disposition of caught sharks, distributions of shark catches relative to those of target 

species) or basic biology (e.g., mean sizes, sex ratios) of the common species. The results 

indicated that blue shark in particular, which historically has comprised approximately 85 

percent of the shark bycatch from the Hawaii longline fishery, exhibits a high rate of survival 

(about 95 percent) to the time of release. On the basis of these very low mortality estimates if 

released, it was concluded that the Hawaii longline fishery has made substantial progress in 

reducing bycatch mortality compared to the period before the shark finning ban. 

Shark Catch Per Unit Effort (CPUE) Data Analysis from Longline Observer Program Data 

NMFS produced standardized CPUE time series for use as input for stock assessments for blue, 

whitetip, and silky shark in the Hawaii longline fishery using the Pacific Islands Regional 

Observer Program data (1995–2010) (Walsh and Clarke, 2011). This work is important because 

these species are taken in large but unknown numbers, primarily as bycatch, in many Pacific 

Ocean fisheries. The standardized CPUE for blue shark was adjusted for the effects of extrinsic 

factors (e.g., geographic position, sea surface temperature, and gear configuration), and will be 

used in an International Scientific Committee for Tuna and Tuna-like Species in the North 

Pacific Ocean (ISC) stock assessment for this species in 2013. 

61
 
 

Insular Shark Surveys 

Densities of insular sharks (Table 5.1) have been estimated at most of the U.S. island possessions
 

within the Tropical Central, Northern, and Equatorial Pacific on annual or biennial surveys
 

conducted by the PIFSC Coral Reef Ecosystem Division (CRED) since 2000.
 

These estimates include surveys of:
 

•	 10 major shallow reefs in the Northwestern Hawaiian Islands (2000, 2001, 2002, 2003, 

2004, 2006, 2008, 2010). 

•	 The Main Hawaiian Islands (2005, 2006, 2008, 2010, 2013, 2015). 

•	 The Pacific Remote Island Areas of Howland and Baker in the U.S. Phoenix Islands and 

Jarvis Island, and Palmyra and Kingman Atolls in the U.S. Line Islands (2000, 2001, 

2002, 2004, 2006, 2008, 2010, 2012, 2015). 

•	 American Samoa, including Rose Atoll and Swains Island (2002, 2004, 2006, 2008, 

2010, 2012, 2015). 

•	 Guam the Commonwealth of the Northern Marianas Islands (2003, 2005, 2007, 2009, 

2011), Johnston Atoll (2004, 2006, 2008, 2010), and Wake Atoll (2005, 2007, 2009, 

2011, 2012, 2015). 

Table 5.2	 Shark species observed in PIFSC-CRED Reef Assessment and Monitoring 

Program surveys around U.S. Pacific Islands. 

Shark species observed 

Common Name Species 

Grey reef shark Carcharhinus amblyrhynchos 

Galapagos shark Carcharhinus galapagensis 

Whitetip reef shark Triaenodon obesus 

Blacktip reef shark Carcharhinus melanopterus 

Silvertip shark Carcharhinus albimarginatus 

Tiger shark Galeocerdo cuvier 

Tawny nurse shark Nebrius ferrugineus 

Whale shark Rhincodon typus 

Scalloped hammerhead shark Sphyrna lewini 

Great hammerhead shark Sphyrna mokarran 

Zebra shark Stegostoma varium 

Although 11 species of shark have been observed during CRED surveys (see Table 5.2), only 

four species are typically recorded in sufficient frequency by towed divers to allow meaningful 

statistical analyses: grey reef shark (Carcharhinus amblyrhynchos), Galapagos shark 

(Carcharhinus galapagensis), whitetip reef shark (Triaenodon obesus), and blacktip reef 

shark(Carcharhinus melanopterus). Analyses show a highly significant negative relationship 

between grey reef and Galapagos shark densities and proximity to human population centers 

(e.g., proxy for potential fishing pressure and other human impacts). Average combined 

numerical density for these two species near population centers is less than 10 percent of 

62
 
 

 

 

 

 

 

 

 

 

densities recorded at the most isolated islands (e.g., no human population, very low present or 

historical fishing pressure or other human activity). Even around islands with no human 

habitation, but within reach of populated areas, grey reef and Galapagos shark densities are only 

between 15 and 40 percent of the population densities around the most isolated near-pristine 

reefs. Patterns in whitetip and blacktip reef shark numbers are similar, but less dramatic. 

Recent analysis of data from 2008 to 2010, also indicated significantly higher biomass of all 

sharks combined at remote islands (i.e., islands at least 100 kilometers from the nearest human 

population center) compared to populated islands, with remote islands having, on average, 40 or 

more times the biomass of sharks than was recorded at populated islands in both the Hawaiian 

and Mariana Archipelagos (I.D. Williams et al. 2011). Differences between remote and 

populated portions of American Samoa were not statistically significant, reflecting low counts of 

sharks at all locations in that region. Because all CRED shark data were gathered by SCUBA 

divers: (1) safe diving practices limited surveys to reefs areas of 30 meters or shallower, which 

is the upper end of reef sharks’ potential depth distribution; and (2) surveys by SCUBA divers 

are potentially biased by acquired behavioral differences of sharks in the presence of divers 

between isolated and fished locations. For those reasons, CRED is pursuing opportunities for 

diver-independent assessments of shark populations, such as by deploying remote video systems. 

Insular Shark Population Model 

PIFSC scientists study the status of reef shark populations in the central-western Pacific Ocean. 

During PIFSC coral reef assessment and monitoring surveys conducted between 2004 and 2010, 

shark observations were recorded around 46 individual U.S. islands, atolls, and banks. PIFSC 

scientists analyzed shark count data from 1,607 towed-diver surveys conducted on fore reefs 

(seaward slope of a reef) using techniques developed specifically to survey large-bodied species 

of reef fishes. 

The shark count data were used to build a computer model capable of explaining observed reef 

shark abundances at various reefs by examining the effects of variables related to human 

impacts, oceanic productivity, sea surface temperature, and reef habitat physical complexity. 

This model was used to predict reef shark densities in the absence of humans (i.e., baseline or 

pristine abundance) and found that current reef shark numbers around populated islands in 

Hawaii, the Mariana Archipelago, and American Samoa are down to about three to ten percent of 

their baseline values (Figure 6.3). These results show the extent of the detrimental effect of 

human activities on reef shark population. However, the exact cause of the decline is not known. 

The likely causes are probably related to prey population depletion (i.e., reef fish biomass around 

populated islands is about 50-80 percent lower than on pristine reefs) and direct removal through 

fishing (bycatch, recreational, or targeted) (Nadon et al. 2012). 

63
 
 

 

Figure 5.3: Mean (SE) observed densities of reef sharks in the U.S. Pacific. Colors represent actual 
 

densities; gray rectangles represent model predictions in the absence of humans.
 

Mitigation of Shark Predation on Hawaiian Monk Seal Pups at French Frigate Shoals 

Shark predation on Hawaiian monk seal pups (Monachus schauinslandi) has become unusually 

common at one breeding site, French Frigate Shoals (FFS) in the Northwestern Hawaiian Islands 

(NWHI). Since 1997, NMFS has frequently observed Galapagos sharks (Carcharhinus 

galapagensis) patrolling and attacking monk seal pups. Tiger sharks (Galeorcerdo cuvier) also 

prey on monk seals and are abundant at FFS; however, Tiger sharks have not been observed to 

attack pups (Gobush 2010, unpublished data). For these reasons, monitoring and mitigation 

efforts at FFS continue to be focused on Galapagos sharks. Shark tagging studies at FFS indicate 

that, although Galapagos sharks are the most abudant shark species, they generally prefer deeper 

water and only a small fraction of the population, equating to a few tens of individuals, likely 

frequents the shallow areas around monk seal pupping islets (Dale et al. 2011). 

Reducing shark predation on pups at FFS is one of several key activities identified in the 

Hawaiian Monk Seal Recovery Plan (NMFS 2007). Since 2000, NMFS has attempted to 

mitigate shark predation through harassment and culling of sharks, shark deterrents, and 

translocation of weaned pups to islets in the atoll with low incidence of shark attacks (Baker et 

al. 2011; Gobush 2010). NMFS implemented a highly selective shark removal project to 

mitigate predation on monk seal pups from 2000-2013, with the exception of 2008–2009 when 

deterrents were tested (see appendix for more details). A total of 14 Galapagos sharks 

frequenting the nearshore areas of pupping islets have been lethally removed to date. In 2009, 

the number of shark sightings and predation incidents at two pupping islets did not differ 

significantly between the control and two experimental treatments: (1) acoustic playback and a 

moored boat, and (2) continuous human presence, versus a control (Gobush and Farry 2012). No 

sharks were removed at French Frigate Shoals in 2013. 

64
 
 

 

 

 

Stock Assessment of Blue Shark 

In 2000, as a collaborative effort with scientists at the National Research Institute for Far Seas 

Fisheries (NRIFSF) in Shimizu, Japan, analyses indicated that the blue shark stock was not being 

overfished (Kleiber et al. 2001). PIFSC and NRIFSF subsequently renewed this collaboration, 

along with scientists from Japan’s Fisheries Research Agency, to update the blue shark 

assessment with the latest data from Japanese and Hawaii based longline fisheries, as well as 

with better estimates of Taiwanese and Korean catch and effort data. 

Objectives were to determine the degree to which the blue shark population has been affected by 

fishing activity and whether current fishing practices need to be managed to ensure continued 

viability and utilization of the resource. In addition to re-estimating catch and effort data based 

on a longer time series of data (Nakano and Clarke 2005, 2006), this study incorporated several 

new features: (1) effort data were obtained from the Fisheries Administration of Taiwan, (2) 

catches for the Japanese inshore longline fleet were included, (3) catch estimates were contrasted 

with estimates from the shark fin trade, (4) catch per unit effort was standardized using both a 

generalized linear model and a statistical habitat model, and (5) two different stock assessment 

models were applied. 

Detailed records from daily fin auctions in the world's largest trading center, Hong Kong, and 

national customs statistics were used to estimate the number of blue sharks caught in the North 

Pacific from 1980 to 2002. This was achieved by estimating the number of blue sharks used in 

the global fin trade (Clarke 2004; Clarke et al. 2004, 2006) and partitioning these estimates to 

represent blue shark catches in the North Pacific only. Despite considerable uncertainty in this 

extrapolation algorithm, the North Pacific blue shark catch estimates based on the shark fin trade 

are very similar to estimates from Kleiber et al. (2001). 

The two shark assessment models—a surplus production model and an integrated age and 

spatially structured model—were found to be in general agreement even though they represent 

opposite ends of the spectrum in terms of data needs (Kleiber et al. 2009). The trends in 

abundance in the production model and all alternate runs of the integrated model show the same 

pattern of stock decline in the 1980s followed by recovery to a biomass that was greater than that 

at the start of the time series. One of the several alternate analyses indicated some probability 

(around 30 percent) that the population is overfished and a lower probability that overfishing 

may be occurring. There was an increasing trend in total effort expended by longline fisheries 

toward the end of the time series, and this trend may have continued thereafter. The uncertainty 

could well be reduced by a vigorous campaign of tagging and by continuous, faithful reporting of 

catches and details of fishing gear. 

Electronic Tagging Studies and Movement Patterns 

PIFSC scientists are using acoustic, archival, and pop-up satellite archival tags (PSATs) to study 

vertical and horizontal movement patterns in commercially and ecologically important tuna, 

billfish, and shark species, as well as sea turtles. The work is part of a larger effort to determine 

the relationship of oceanographic conditions to fish and sea turtle behavior patterns. This 

information is intended for incorporation into population assessments, addressing fisheries 

interactions and allocation issues, as well as improving the overall management and conservation 

of commercially and recreationally important tuna and billfish species, sharks, and sea turtles. 

65
 
 

 

 

 

 

 

 

 

 

PIFSC is finishing manuscripts detailing the movements of pelagic sharks in relation to 

oceanographic conditions (Musyl et al. 2011a). In a review paper, Bernal et al. (2009) 

summarizes the eco-physiology of large pelagic sharks while Sibert et al. (2009) report on the 

error structure of light-based geolocation estimates afforded by PSATs and Nielsen et al. (2009) 

show how reconstructed PSAT tracks can be optimized. 

The research, sponsored by the Pelagic Fisheries Research Program (University of Hawaii) and 

PIFSC, has shown that some large pelagic fishes have much greater vertical mobility than others. 

Pelagic sharks displayed species-specific depth and temperature ranges, although with significant 

individual temporal and spatial variability in vertical movement patterns, which were also 

punctuated by stochastic events, like theEl Niño-Southern Oscillation (ENSO). Pelagic species, 

including some other species that have been PSAT tagged (swordfish, bigeye tuna, and marlins) 

can be separated into three broad groups (Figure 6.4) based on daytime temperatures occupied 

using a clustering algorithm. These groups and the temperatures occupied by the sharks are 

characterized as: 

(1) Epipelagic species (including silky and oceanic whitetip sharks) which spent more than 

95 percent of their time at temperatures within 2°C of sea surface temperature; 

(2) Mesopelagic I species (including blue and shortfin mako sharks) which spent 95 percent 

of the time at temperatures from 9.7–26.9°C and 9.4–25.0°C, respectively; and 

(3) Mesopelagic II species (including bigeye thresher shark) which spent 95 percent of the 

time at temperatures from 6.7–21.2°C. 

For the most part, the topology of clusters did not appear to correlate with ENSO variability, 

phylogeny, life history characteristics, ecomorphotypes, neural anatomy, relative eye size, 

physiology, or the presence of regional endothermy—indicating other factors (e.g., ontogeny, 

latitude, locomotion, diet, and dimensionality of the environment) influence the structure as well 

as the spatial and temporal stability of thermal habitats. The results suggest that habitat structure 

for the epipelagic silky and oceanic whitetip sharks can be adequately estimated from two 

dimensions given that these species spend most of their time in the warmest available water. In 

contrast, three dimensions will be required to describe the extended vertical habitat of the species 

that we classified as mesopelagic I (blue shark, shortfin mako shark) and mesopelagic II (bigeye 

thresher shark) (Musyl et al. 2011a). 

66
 
 

 

 

 

 

Figure 5.4: Clustered relationships among pelagic animals using daytime temperature preferences from
 

pop-up satellite archival tags (PSATs). B = blue shark, SF = shortfin mako, T = bigeye thresher, E =
 

bigeye tuna, R = swordfish, S = silky shark, O = oceanic whitetip shark, K = black marlin, L = blue
 

marlin, M = male, and F = female. Inset maps show the horizontal movement patterns.
 

Mesopelagic II species remain in the vicinity of prey organisms comprising the deep Sound 

Scattering Layer (SSL) during their extensive diel vertical migrations. The SSL comprises 

various species of squids, mesopelagic fish, and euphausiids that undertake extensive diurnal 

vertical migrations. This composition of organisms is referred to as the SSL because the 

migration of these organisms was first discovered by the sound waves that reflect off gas-filled 

swim bladders or fat droplets within the migrating organisms. PIFSC scientists have also found 

one of the most ubiquitous large-vertebrate species in the pelagic environment—the blue shark— 

occasionally displays vertical movement behaviors similar to those of swordfish, bigeye tuna, 

and bigeye thresher sharks. 

Electronic Tagging of Whale Sharks (Rhincodon typus) 

The PIFSC, in collaboration with Australian Institute for Marine Science and the Commonwealth 

Scientific and Industrial Research Organization, has for the past several years been deploying 

electronic tags on whale sharks at Ningaloo Reef, Western Australia, to describe their vertical 

and horizontal movements. The work has documented that whale sharks dive below 1,000 

meters, deeper than previously thought. After the whale sharks leave Ningaloo Reef, some travel 

to Indonesia while others head across the Indian Ocean (Wilson et al. 2006, 2007). 

67
 
 

 

 

 

 

 

 

 

 

Chemical and Electromagnetic Deterrents to Bycatch 

One study funded by the NMFS National Bycatch Program since 2005 seeks to test the use of 

chemical and electromagnetic deterrents to reduce shark bycatch. Previous research by Eric 

Stroud of Shark Defense, LLC, was conducted to identify and isolate possible semiochemical 

compounds from decayed shark carcasses. Semiochemicals are chemical messengers that sharks 

use to orient, survive, and reproduce in their specific environments. Certain semiochemicals 

have the ability to trigger a flight reaction in sharks. Initial tests showed that chemical repellents 

administered by dosing a “cloud” of the repellent into a feeding school of sharks caused 

favorable behavioral shifts, and teleost fishes such as pilot fish and remora accompanying the 

sharks were not repelled and continued to feed. This suggested other teleosts, such as longline 

target species like tunas or billfish, would not be repelled. Longline field testing of these 

chemicals and magnets was conducted in early 2006 with demersal longline sets in South Bimini 

and were quite successful. 

Beginning in early 2007, the PIFSC began testing the ability of electropositive metals (lanthanide 

series) to repel sharks from longline hooks. Electropositive metals release electrons and generate 

large oxidation potentials when placed in seawater. It is thought that these large oxidation 

reactions perturb the electrosensory system in sharks and rays, causing the animals to exhibit 

aversion behaviors. Since commercially targeted pelagic teleosts do not have an electrosensory 

sense, this method of perturbing the electric field around baited hooks may selectively reduce the 

bycatch of sharks and other elasmobranchs. 

Feeding behavior experiments were conducted to determine whether the presence of these metals 

would deter sharks from biting fish bait. Experiments were conducted with Galapagos sharks 

and sandbar sharks off the coast of the North Shore of Oahu. Results indicate that sharks 

significantly reduced their biting of bait associated with electropositive metals. In addition, 

sharks exhibited significantly more aversion behaviors as they approached bait associated with 

these metals. Further studies on captive sandbar sharks in tanks indicated sharks would not get 

any closer than 40 centimeters to bait in the presence of the metal, with the metal approximately 

the size of a 60 gram lead fishing weight. 

Initial experiments to examine the effects on shark catch rates of modified longlines are also 

being conducted. This is being accomplished through collaboration with Dr. Kim Holland of the 

University of Hawaii’s Hawaii Institute of Marine Biology (HIMB). Two experiments were 

initiated, one focusing on the effects of peodymiun/praseodymium (Nd/Pr) alloy on the catch 

rates of sharks on bottom set longline gear and the other examining the effects of Nd/Pr alloy and 

other lanthanide alloys on the feeding and swimming behavior of scalloped hammerhead 

(Sphyrna lewini) and sandbar (Carcharhinus plumbeus) sharks. Preliminary results from 

longline field trials in Kaneohe Bay, Hawaii, suggest that catch rates of juvenile scalloped 

hammerhead sharks are reduced by 63 percent on branch lines with the Nd/Pr alloy attached as 

compared to lead weight controls (Figure 6.5). Initial behavioral experiments examining effects 

on swimming behavior have been initiated (Wang et al. 2009, Brill et al. 2009). 

68
 
 

 

 

 

 

 

 

CPUE of scalloped hammerhead sharks 

(Sphyrna lewini) 

8.0E-02 

7.0E-02 

6.0E-02 

5.0E-02 

4.0E-02 

3.0E-02 

2.0E-02 

1.0E-02 

0.0E+00 

2.2E-02 

6.2E-02 

Control Hooks Hooks w/ Nd-Pr 

Hook Treatment 

Figure 5.5: Catch per unit effort of scalloped
 

hammerhead sharks on longlines with Nd/Pr
 

alloy attached versus control hooks.
 

In addition, field trials on pelagic sharks were initiated via collaboration with the Southwest 

Fisheries Science Center (SWFSC). 13 sets were completed for the experiment during the 2010 

cruise in addition to the 25 sets completed in 2009. Preliminary results indicate that the rare 

earth metals did not affect the catch rate of shortfin mako or blue sharks, as they were caught on 

the experimental hooks and control hooks in almost equal numbers. These results differ from 

those found on some coastal shark species where the deterrents proved effective at lowering 

catch rates. The data are being further examined based on size, sex, and other potential factors 

before drawing final conclusions. 

A collaborative pilot study in the Ecuadorian mahi-mahi longline fisheries was also conducted. 

Branch lines with lead weight were alternated with branch lines with Nd/Pr metal weight. 

However, analysis of catch data indicated no difference in the catch rates of thresher sharks, 

silky sharks, and scalloped hammerhead sharks between control branch lines and branch lines 

with Nd/Pr metal (Wang et al. 2010, Hutchinson et al. 2012). 

While electropositive metal deterrents have been tested experimentally as a potential bycatch 

solution on pelagic longline fisheries (Hutchinson et al., 2012), trials conducted in commercial 

fishing conditions are still needed. PIFSC in collaboration with Dalhousie University completed 

a study in the northwest Atlantic with the Canadian pelagic longline swordfish fishery where 

blue sharks comprise a significant proportion of unwanted bycatch. A total of seven sets (6,300 

hooks) with three hook treatments—standard hooks, hooks with rare-earth alloys (Nd/Pr), and 

hooks with lead weights—were deployed off a commercial longliner near Sambro, Nova Scotia. 

Results suggest that rare-earth metals do not have any significant deterrent effect on the most 

common shark bycatch species and as such do not appear to be a practical bycatch mitigation 

option in the Canadian fishery (Godin et al., 2013). 

Bycatch of sharks in longline fisheries has contributed to declines in shark populations and 

prompted the need for exploring novel technologies to reduce the incidental capture of sharks. 

One potential strategy is to exploit the unique electrosensory system of sharks, which are capable 

69
 
 

 

 

 

 

 

of detecting weak electric fields. Several shark species have been shown to be repulsed by 

powerful magnets and rare earth metals such as the electropositive metals from the lanthanide 

series, made up of neodymium (Nd) and praseodymium (Pr). For this reason, electromagnetic 

deterrents have become a potential bycatch solution on pelagic longline fisheries, as they may 

selectively reduce the bycatch of sharks and other elasmobranchs without affecting the catch of 

commercially targeted pelagic teleosts. 

Longline Hook Effects on Shark Bycatch 

To explore operational differences in the longline fishery that might reduce shark bycatch, the 

observer database is being used to compare bycatch rates under different operational factors 

(e.g., hook type, branch line material, bait type, the presence of light sticks, soak time, etc.). A 

preliminary analysis was completed that compared the catches of vessels using traditional tuna 

hooks to vessels voluntarily using size 14/0 to 16/0 circle hooks in the Hawaii-based tuna fleet. 

The study was inconclusive due to the small number of vessels using the circle hooks. 

Subsequently, 16 contracted vessels were used to test large (size 18/0) circle hooks versus 

traditional Japanese-style tuna hooks (size 3.6 sun) in controlled comparisons. Preliminary 

analysis does not indicate these large circle hooks increase the catch rate of sharks, in contrast to 

findings of increased shark catch on circle hooks in studies comparing smaller circle hooks with 

J hooks in other fisheries. The 18 most caught species were analyzed, representing 97.6 percent 

of the total catch by number. Catch rates on large 18/0 circle hooks were significantly reduced— 

by 17 percent for blue shark, 27 percent for bigeye thresher shark, and 69 percent for pelagic 

stingray. Bycatch rates for other incidental species such as billfish, opah (Lampris guttatus), and 

mahimahi (Coryphaena hippurus) were also reduced compared to traditional tuna hooks. There 

was no significant difference in the catch rate of the target species, bigeye tuna, by hook type. In 

contrast to tuna hooks, large circle hooks have conservation potential for use in the world’s 

pelagic tuna longline fleets for some highly migratory species based on demonstrated catch rate 

reductions (Curran and Bigelow 2010, 2011). 

Testing Deeper Sets 

An experiment with deeper set longline gear conducted in 2006 altered current commercial tuna 

longline setting techniques by eliminating all shallow set hooks (less than 100 meters depth) 

from tuna longline sets (Beverley et al. 2009). The objective was to maximize target catch of 

deeper dwelling species such as bigeye tuna, and reduce incidental catch of many marketable but 

less desired species (e.g., billfish and sharks). The deep setting technique was easily integrated 

into daily fishing activities with only minor adjustments in methodology. The main drawback 

for the crew was increased time to deploy and retrieve the gear. Catch totals of bigeye tuna and 

sickle pomfret were greater on the deep set gear than on the controlled sets; but the bigeye results 

were not statistically significant. Catch of several less valuable incidental fish (e.g., blue marlin, 

striped marlin, shortbill spearfish, dolphinfish, and wahoo) was significantly lower on the deep 

set gear than the controlled sets. Unfortunately, no significant results were found for sharks. 

Results from several of the bycatch studies suggest combining methods to avoid bycatch. 

Perhaps a combination of electropositive metals fashioned into weights attached to longline gear 

and setting the gear deeper might avoid bycatch of sharks and marlins. Research is also being 

initiated to develop safer weights, including weights that do not spring back toward fishermen 

when branch lines break. 

70
 
 

 

 

 

 

Improved Release Technology 

The recently resumed Hawaii-based swordfish longline fishery, as well as the tuna longline 

fishery, is required to carry and use dehookers for removing hooks from sea turtles. These 

dehookers can also be used to remove external hooks and ingested hooks from the mouth and 

upper digestive tract of fish, and could improve post-release survival and condition of released 

sharks. Sharks are generally released from the gear by one of the following methods: (1) 

severing the branch line; (2) hauling the shark to the vessel to slice the hook free; or (3) dragging 

the shark from the stern until the hook pulls free. Fishermen are encouraged to use dehooking 

devices to minimize trauma and stress of bycatch by reducing handling time and to mitigate posthooking mortality. 

Testing of the dehookers on sharks during research cruises has indicated that removal of circle 

hooks from shark jaws with the dehookers can be quite difficult. PIFSC is looking into the 

feasibility of barbless circle hooks for use on longlines, which would make it easier to dehook 

unwanted catch with less harm. Preliminary research in the Hawaii shore fishery has indicated 

that barbless circle hooks catch as much as barbed hooks, but the situation could be different 

with more passive gear such as longlines, where bait must soak unattended for much of the day 

and fish have an extended period in which to try to throw the hook. Initial results from very 

limited longline testing of barbless hooks on research cruises in American Samoa, and in 

collaboration with NMFS Narragansett Laboratory, indicated a substantial increase in bait loss 

using barbless hooks. Subsequent testing used rubber retainers to prevent bait loss. Summary 

information from before and after the use of bait retainers showed no difference between barbed 

and barbless hooks in the catch and catch rates of targeted species and sharks, although catches 

have so far been too few to provide much statistical power. Also in this study, the efficacy of the 

pigtail dehooker (the device required by U.S. regulations for releasing sea turtles) showed a 67 

percent success rate in dehooking and releasing live sharks on barbless hooks, compared to a 0 

percent success rate when used with sharks caught on barbed hooks. In 2007, PIFSC and Pacific 

Islands Regional Office (PIRO) personnel conducted longline trials along the eastern shore of 

Virginia to compare catches of sharks and rays on barbed and barbless circle hooks. In a 

randomization test, difference in the catches between the hook types was not significant. Circle 

hook removal trials were also conducted simultaneously and resulting effectiveness of removing 

hooks from sharks were 27 percent with barbed hooks and 72 percent with barbless hooks. 

During the study a new dehooker was developed and tested. Preliminary results were more than 

90 percent effective in removing both barbed and barbless circle hooks from sharks; however, 

the prototype appears to be more efficient on smaller animals. 

Post-release Survival and Biochemical Profiling 

Successful management strategies in both sport and commercial fisheries require information 

about long-term survival of released fish. Catch-and-release sport fishing and non-retention of 

commercially caught fish are justifiable management options only if there is a reasonable 

likelihood that released fish will survive for long periods. All recreational anglers and 

commercial fisherman who practice catch-and-release fishing hope the released fish will survive, 

but it is often not known what proportion of released fish will survive. Many factors, like fish 

size, water temperature, fight time, and fishing gear could influence survival. 

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Post-release survival is typically estimated using tagging programs. Historically, large-scale 

conventional tagging programs were used. These programs yielded low return rates, consistent 

with a high post-release mortality. For example, in a 30-year study of Atlantic blue sharks, only 

5 percent of tags were recovered. Short-duration studies using ultrasonic telemetry have shown 

that large pelagic fish usually survive for at least 24 to 48 hours following release from sport 

fishing or longline gear. PIFSC researchers and collaborators from other agencies, academia, 

and industry have been developing alternative tools to study longer-term post-release mortality. 

Whereas tagging studies assess how many fish survive, new approaches are being used to 

understand why fish die. A set of diagnostic tools is being developed to assess the biochemical 

and physiological status of fish captured on various gear. These diagnostics are being examined 

in relation to survival data obtained from a comprehensive PSAT program. Once established as 

an indicator of survival probability, such biochemical and physiological profiling could provide 

an alternative means of assessing consequences of fishery release practices. 

PIFSC scientists have been developing biochemical and physiological profiling techniques for 

use in estimating post-release survival of blue sharks, which are frequently caught as bycatch by 

Pacific longliners. Using NOAA research vessels, they captured 211 sharks, of which 172 were 

blue sharks. Using blue sharks, PIFSC scientists and collaborators developed a model to predict 

long-term survival of released animals (verified by PSAT data) based on analysis of small blood 

samples. Five parameters distinguished survivors from moribund sharks: plasma Mg2+, plasma 

lactate, erythrocyte Hsp70 mRNA, plasma Ca2+, and plasma K+. A logistic regression model 

incorporating a combination of Mg2+ and lactate successfully categorized 19 of 20 (95 percent) 

fish of known fate and predicted that 21 of 22 (96 percent) sharks of unknown fate would have 

survived upon release. These data suggest that a shark captured without obvious physical 

damage or physiological stress (the condition of 95 percent of the sharks they captured) would 

have a high probability of surviving upon release (Moyes et al. 2006). 

In the second approach PIFSC and colleagues deployed 71 PSATs on the five most commonly 

caught species of pelagic shark in the Hawaii-based commercial longline fishery (blue shark 

(Prionace glauca), shortfin mako (Isurus oxyrinchus), silky shark (Carcharhinus falciformes), 

oceanic whitetip (C. longimanus), and bigeye thresher (Alopias superciliosus)) to determine 

species-specific horizontal and vertical movement patterns and survival after release from 

longline fishing gear. All five species have life-history characteristics that make populations 

vulnerable to exploitation, and there is little or no information about their movement patterns and 

habitats. Results indicated that only a single post-release mortality could be unequivocally 

documented: male blue shark that succumbed seven days post-release. The depth and 

temperature data suggest that this one mortality was due to injuries sustained during capture and 

handling, rather than predation. Meta-analysis on blue shark mortality from published and 

ongoing research (n=78 reporting PSATs) indicated the summary effect for post-release 

mortality from longline gear was 15 percent (95 percent CI, 9 – 25 percent). 

Antecedent stress variables to explain mortality have been examined (i.e., capture temperature, 

soak time, etc.) but NMFS could not conclusively demonstrate association with any of the 

variables and mortality in these two instances. These combined biochemical and PSAT analyses 

suggest that sharks landed in an apparently healthy condition are likely to survive long term if 

released (95 percent survival based on biochemical analyses for blue shark; greater than 95 

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percent based on PSATs for all sharks studied). In summary, studies demonstrate a high rate of 

post-release survival of pelagic sharks captured and released from longline gear fished with 

circle hooks. These tagging results are also used to chronicle these pelagic species in terms of 

migration routes, distribution patterns, and habitat association as well as developing bycatch 

mitigation methods (Musyl et al. 2009, Beverley et al. 2009, Hoolihan et al. 2011). 

Pop-up Satellite Archival Tags (PSAT) Studies on Horizontal and Vertical Movement Patterns 

Management strategies for mitigating bycatch in large-scale commercial fisheries require 

estimates of post-release survival as well as information about habitats and movement patterns in 

captured teleosts, elasmobranchs, and sea turtles. Large pelagic sharks (particularly blue shark 

(Prionace glauca)) are the majority of the bycatch in pelagic gill nets and longline fisheries 

targeting swordfish (Xiphias gladius). Pop-up satellite archival tags (PSATs) deployed on 

pelagic sharks caught in commercial longline fisheries can be used to determine species-specific 

horizontal and vertical movement patterns and survival after release from longline fishing gear. 

Analysis of PSATs deployed on pelagic sharks released in the Hawaii-based longline fishery in 

the central Pacific Ocean revealed sharks displayed species-specific depth and temperature 

ranges, although with significant individual temporal and spatial variability in vertical movement 

patterns. Distinct thermal niche partitioning based on daytime temperature preferences was 

evident: 

(1) Epipelagic species (silky and oceanic whitetip sharks), which spent more than 95 percent 

of their time at temperatures within 2°C of sea surface temperature; 

(2) Mesopelagic-I species (blue sharks and shortfin makos), which spent 95 percent of their 

time at temperatures from 9.7° to 26.9°C and from 9.4° to 25.0°C, respectively; and 

(3) Mesopelagic-II species (bigeye threshers), which spent 95 percent of their time at
 

temperatures from 6.7° to 21.2°C (Musyl et al. 2011a). 

This knowledge could allow targeting of longline gear to create mismatches between hook depth 

and the sharks’ habitat (i.e., minimize vulnerability of the species to be avoided) (Beverly et al. 

2009). 

Pop-up Satellite Archival Tags (PSAT) Performance and Metadata Analysis Project 

Satellite tagging studies have been used to investigate post-release mortality of animals, either as 

indicated by signal failure, early pop-up, or depth data indicating rapid descent to abnormal 

depth before pop-up. However, these signals, or the lack thereof, may have other origins besides 

mortality. The purpose of this study is to explore failure (or success) scenarios in PSATs 

attached to pelagic fish, sharks, and turtles. We quantify these issues by analyzing reporting 

rates, retention times, and data return from 27 pelagic species from 2,164 deployments (731 

PSAT deployments from 19 species in the authors’ database, and in 1,433 PSAT deployments 

from 24 species summarized from 53 published articles). Shark species in the database include 

bigeye thresher, blue, shortfin mako, silky, oceanic whitetip, great white, and basking sharks. 

Other species include: black, blue, and striped marlins; broadbill swordfish; bigeye, yellowfin, 

and bluefin tunas; tarpon; and green, loggerhead, and olive ridley turtles. To date, of 731 PSATs 

attached to sharks, billfish, tunas, and turtles, 577 (79 percent) reported data. Of the tags that 

recorded data, 106 (18 percent) hit their programmed pop-off date and 471 tags popped off 

earlier than their program date. The 154 (21 percent) non-reporting tags are not assumed to 

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reflect fish mortality. The metadata study is designed to look for explanatory variables related to 

tag performance by analyzing PSAT retention rates, percentage of satellite data (i.e., depth, 

temperature, geolocations) retrieved, and tag failure. By examining these factors and other 

information about PSATs attached to vastly different pelagic species, it is anticipated certain 

patterns/commonalties may emerge to help improve attachment methodologies, selection of 

target species, and experimental designs, particularly with respect to post-release survival 

studies. PSATs in the database had an overall reporting rate of 0.79, which was not significantly 

different (p=0.13) from the PSAT reporting rate of 0.76 in the meta-analysis. Logistic regression 

models showed that reporting rates have improved significantly over recent years and are lower 

in species undertaking large vertical excursions, with a significant interaction between species’ 

depth class (i.e., littoral, epi-pelagic, meso-pelagic, bathy-pelagic) and tag manufacturer. 

Of all the PSATs attached to sharks, 80 percent reported and 65 percent detached before the 

programmed pop-up date. Shark PSAT reporting rates were highest in species such as oceanic 

whitetip (81 percent), which were epipelagic and remained near the ocean surface. Reporting 

rates were lowest in species undertaking large (~1,000 meters) vertical excursions, such as 

bigeye thresher (37 percent) and shortfin mako (40 percent). Tag retention for the three shark 

species averaged 155 days for oceanic whitetip, 220 days for bigeye thresher, and 164 days for 

shortfin mako. Species-specific reporting rates were used to make recommendations for future 

PSAT sampling designs for fisheries researchers. Information derived from this study should 

allow an unprecedented and critical appraisal of the overall efficacy of the technology (Musyl et 

al., 2011b). 

Pop-up Satellite Archival Tags (PSAT) and Post-release Survival 

Successful management strategies in both sport and commercial fisheries require information 

about long-term survival of released fish. Satellite tagging studies have been used to investigate 

post-release mortality of animals, either as indicated by signal failure, early pop-up, or depth data 

indicating rapid descent to abnormal depth before pop-up. Shark PSAT reporting rates were 

highest in species such as oceanic whitetip (81 percent) that were epipelagic and remained near 

the ocean surface. Reporting rates were lowest in species undertaking large (~1,000 m) vertical 

excursions, such as bigeye thresher (37 percent) and shortfin mako (40 percent). Meta-analysis 

on blue shark mortality from published reports and the current study (n=78 reporting PSATs) 

indicated the summary effect of post-release mortality from longline gear was 15 percent (95 

percent CI, 9 – 25 percent), and suggested that catch-and-release in longline fisheries can be a 

viable management tool to protect parental biomass in shark populations (Musyl et al., 2011a). 

PIFSC studies also demonstrated a high rate of post-release survival of pelagic sharks captured 

and released from longline gear fished with circle hooks. 

Reducing Longline Shark Bycatch 

The resumption of the previously closed Hawaii shallow-set longline fishery for swordfish in late 

2004 and continuing through 2007 was anticipated to increase blue shark catches, as in the past 

blue sharks made up about 50 percent of the total catch in this fishery. With the ban on shark 

finning, these sharks are not retained and are categorized as regulatory bycatch. Although the 

anticipated increase in shark bycatch has been less than expected (perhaps due to the requirement 

to use fish bait instead of squid, or because of a shift toward an earlier fishing season in the 

reopened swordfish fishery), researchers at PIFSC have undertaken several projects to address 

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shark bycatch on longlines (Huang et al. 2013; Hutchinson et al. 2012; Swimmer et al. 2008, 

2011). The use of large circle hooks instead of conventional tuna hooks in the world’s pelagic 

tuna longline fleets has displayed conservation potential for some highly migratory species 

(Curran and Bigelow 2010, 2011). However, recent collaborative research on capture rates of 

species caught on Japanese tuna hooks vs. relatively large circle hooks conducted on a 

Taiwanese commercial longline vessel indicated significantly higher catch rates of blue sharks 

caught on circle hooks (Huang et al. 2013). Additionally, research in the South Atlantic Ocean 

conducted on a Uruguayan longline vessel found higher rates of capture of shortfin mako sharks 

on circle hooks compared to J hooks (Domingos et al. 2012). 

Southeast Fisheries Science Center (SEFSC) 

Shark Longline Program 

This program is designed to meet the intent of the ESA and the Consolidated Atlantic HMS 

Fishery Management Plan (FMP). It was created to obtain better data on catch, bycatch, and 

discards in the shark bottom longline fishery. While on board the vessel, the observer records 

information on gear characteristics and all species caught, condition of the catch (e.g., alive, 

dead, damaged, or unknown), and the final disposition of the catch (e.g., kept, released, finned, 

etc.). Recent amendments to the Consolidated Atlantic HMS FMP based on updated stock 

assessments have significantly modified the major directed shark fishery in the U.S. Atlantic. 

The amendments implement a shark research fishery, which allows NMFS to select a limited 

number of commercial shark vessels on an annual basis to collect life history data and catch data 

for future stock assessments. Furthermore, the revised measures drastically reduce quotas and 

retention limits, and modify the authorized species in commercial shark fisheries. Specifically, 

commercial shark fishers not participating in the research fishery are no longer allowed to land 

sandbar sharks (Carcharhinus plumbeus), which have been the main target species. Outside the 

research fishery, fishers are permitted to land 36 non-sandbar large coastal sharks. In 2008, 

NMFS announced its request for applications for the shark research fishery from commercial 

shark fishers with a directed or incidental permit. Based on the temporal and spatial needs of the 

research objectives, and the available quota, 11 qualified applicants were selected for observer 

coverage in 2008, seven in 2009, nine in 2010 and 2011, and six in 2012, 2013, and 2014. These 

vessels carried observers on 100 percent of trips. Outside the research fishery, vessels targeting 

shark and possessing current valid directed shark fishing permits were randomly selected for 

coverage with a target coverage level of 4 to 6 percent. 

Shark Gillnet Program 

Since 1993, an observer program has been in place to estimate catch and bycatch in the directed 

shark gillnet fisheries along the southeastern U.S. Atlantic coast. This program was designed to 

meet the intent of the Marine Mammal Protection Act (MMPA), the ESA, and the 1999 revised 

FMP for HMS. It was also created to obtain better data on catch, bycatch, and discards in the 

shark fishery. Historically, the Atlantic Large Whale Take Reduction Plan and the Biological 

Opinion issued under Section 7 of the Endangered Species Act mandated 100 percent observer 

coverage during the right whale calving season (November 15 to April 1). Outside the right 

whale calving season, observer coverage equivalent to 38 percent of all trips was maintained. In 

2007, the regulations implementing the Atlantic Large Whale Take Reduction Plan were 

amended and included the removal of the mandatory 100 percent observer coverage for drift 

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gillnet vessels during the right whale calving season, but now prohibit all gillnets in an expanded 

southeast United States restricted area that covers an area from Cape Canaveral, Florida, to the 

North Carolina-South Carolina border, from November 15 through April 15. The rule has 

limited exemptions, only in waters south of 29 degrees N latitude, for shark strike net fishing2 

during this same period, and for Spanish mackerel gillnet fishing in December and March. 

Based on these regulations and on current funding levels, the shark gillnet observer program now 

covers a portion of all anchored (sink, stab, set), strike, or drift gillnet fishing by vessels that fish 

from Florida to the North Carolina year-round. All observers must record information on all 

gear characteristics, species caught, condition of the catch, and the final disposition of the catch. 

A total of 237 sets comprising various gillnet fisheries were observed in 2014. Set locations 

ranged from North Carolina to the Florida Keys in the Atlantic Ocean and the Gulf of Mexico. 

Trips were made targeting one or more of the following: mixed shark species, king mackerel 

(Scomberomorus cavalla), smooth dogfish (Mustelus canis), Spanish mackerel (Scomberomorus 

maculates), southern kingfish (Menticirrhus americanus), and mixed teleosts, including Atlantic 

croaker (Micropogonias undulates), bluefish (Pomatomus saltatrix), and mixed teleost species). 

Determination of critical habitat for the conservation of dusky shark (Carcharhinus obscurus) 

using satellite archival tags 

In an attempt to improve the conservation status of dusky shark, NMFS established a time-area 

closure off North Carolina from January to July to reduce bycatch of neonate and juvenile dusky 

sharks. To better evaluate the closed area and determine critical habitat of dusky shark, we are 

deploying PSATs. Based on geolocation data, sharks generally traveled about 21 kilometers per 

day with an average of 433 kilometers in total. Overall, mean proportions of time at depth 

revealed dusky sharks spent the majority of their time in waters 20–40 meters deep, but did dive 

to depths of 440 meters. Tagged sharks had varied movement patterns. One shark tagged off 

Key Largo, Florida, in January moved north along the east coast of the United States to the North 

Carolina/Virginia border in June. A second shark tagged off Key Largo in March traveled south 

toward Cuba. The third shark, tagged off North Carolina in March, moved little from where it 

was initially tagged, but problems with estimating the geolocation precluded researchers from 

fully determining its movement patterns in and around the closed area. Four dusky sharks were 

tagged in 2014; the tag pulled early on one animal, one animal traveled 311 kilometers onto the 

Blake Plateau before it died near Jacksonville, Florida after 126 days; the remaining two animals 

died within 76 and 85 days of release, respectively. 

Habitat use and movement patterns of dusky sharks (Carcharhinus obscurus) in the northern 

Gulf of Mexico. 

The dusky shark (Carcharhinus obscurus) is the largest member of the genus Carcharhinus and 

inhabits coastal and pelagic ecosystems circumglobally in temperate, subtropical and tropical 

marine waters. In the western North Atlantic Ocean (WNA), dusky sharks are overfished and 

considered vulnerable by the International Union for the Conservation of Nature. As a result, 

retention of dusky sharks in commercial and recreational fisheries off the east coast of the United 

States (US) and in the northern Gulf of Mexico is prohibited. Despite the concerns regarding the 

status of dusky sharks in the WNA, little is known about their habitat utilization. During the 

2 When a vessel fishes for sharks with strike nets, the vessel encircles a school of sharks with a gillnet. This is 

usually done during daylight hours, to allow visual observation of schooling sharks from the vessel or by using a 

spotter plane. 

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summers of 2008 and 2009, pop-up satellite archival tags were attached to ten dusky sharks (one 

male, nine females) at a location where they have been observed to aggregate in the north central 

Gulf of Mexico southwest of the Mississippi River Delta to examine their movement patterns 

and habitat utilization. All tags successfully transmitted data with deployment durations ranging 

from 6 to 124 days. Tag data revealed shark movements in excess of 200 kilometers from initial 

tagging locations, with sharks primarily utilizing offshore waters associated with the continental 

shelf edge from Desoto Canyon to the Texas/Mexican border. While most sharks remained in 

US waters, one individual moved from the northern Gulf of Mexico into the Bay of Campeche 

off the coast of Mexico. Sharks spent 87 percent of their time between 20 and 125 m and 83 

percent of their time in waters between 23 and 30 °C. Since dusky sharks are among the most 

vulnerable shark species to fishing mortality, there is a recovery plan in place for US waters; 

however, since they have been shown to make long-distance migrations, a multi-national 

management plan within the WNA may be needed to ensure the successful recovery of this 

population. 

Electronic Tagging Studies and Movement Patterns of Large Pelagic Sharks 

SEFSC scientists are using fin-mounted smart position tags (SPOT) to study the horizontal 

movement patterns of tiger (Galeocerdo cuvier), scalloped (Sphyrna lewini) and great (S. 

mokarran) hammerheads in the Gulf of Mexico (tiger, scalloped, and great hammerhead). This 

work is part of a collaborative effort with Louisiana Department of Wildlife and Fisheries and 

the University of Southern Mississippi. The information collected in this study is intended to 

address fisheries interactions, and improve the management and conservation of these 

ecologically important sharks in the Gulf of Mexico. In 2014, fin-mounted SPOT tags were 

deployed on 23 sharks; 18 scalloped hammerheads, 5 tiger sharks, and 3 great hammerheads. 

Tags from 18 of the 23 sharks (15 scalloped hammerhead, 5 tiger, and 1 great hammerhead) 

reported location data with a mean reporting duration of approximately 90 days, with one tiger 

shark reporting locations over a one year. The lone reporting great hammerhead spent the 

majority of its time nearshore, while both scalloped hammerheads and tiger sharks traversed 

continental shelf and slope waters. Data are being analyzed to investigate any possible season, 

sex, and size differences in movement patterns. 

Electronic Tagging of Whale Sharks (Rhincodon typus) 

The SEFSC, in collaboration with Louisiana Department of Wildlife and Fisheries and the 

University of Southern Mississippi, has been deploying pop-up satellite archival tags (PSAT) 

and towable smart position tags (SPOT) for the past several years on whale sharks in the 

northern Gulf of Mexico to describe their vertical and horizontal movements. In 2014, 10 PSAT 

and 2 SPOT tags were deployed on whale sharks during a large aggregation encounter on July 

10th at Ewing Bank, a topographic feature off the coast of Louisiana. All PSAT tags reported 

data. Six of the tags remained on the sharks for longer than seven months and three were 

retained for a full year. The sharks spent the majority of their time in the northern Gulf of 

Mexico; however, several individuals utilized the southwest Gulf of Mexico during the fall and 

winter. None of the sharks left the Gulf of Mexico. With the addition of the 2014 tags, nearly 

35 tags have been deployed on whale sharks in the northern Gulf of Mexico and a detailed 

analysis of the data is currently underway. 

New record of a goblin shark Mitsukurina owstoni (Lamniformes: Mitsukurinidae) in 

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the western North Atlantic Ocean 

On 19 April 2014, a female goblin shark, Mitsukurina owstoni, was captured in a commercial 

shrimp trawl in the northern Gulf of Mexico. The shark, estimated to be approximately 5 meters 

in length, was captured at a depth of approximately 490 meters and released alive shortly after 

capture. This specimen represents the second goblin shark ever recorded in the Gulf of Mexico. 

Do Vertebral Chemical Signatures Distinguish Juvenile Blacktip Shark (Carcharhinus 

limbatus) Nursery Regions in the Northern Gulf of Mexico? 

Identifying and protecting shark nurseries is a common management strategy used to help 

rebuild overfished stocks yet we know little about connectivity between juvenile and adult 

populations. By analyzing trace metals incorporated into vertebral cartilage, it may be possible 

to infer natal origin based on nursery-specific chemical signatures. To assess the efficacy of this 

approach, we collected juvenile blacktip sharks, Carcharhinus limbatus, (n = 93) from four 

regions in the Gulf of Mexico in 2012 and 2013 and analyzed their vertebral centra with laser 

ablation–inductively coupled plasma–mass spectrometry (LA–ICP–MS). Changes in Sr:Ca, 

Ba:Ca, and Pb:Ca concurrent with birth were consistent with changes from a marine environment 

to one influenced by freshwater input. Multi–element chemical signatures were significantly 

different among regions and year-classes. Year–class specific linear discriminant function 

analysis (LDFA) yielded classification accuracies of 81 percent for 2012 and 85 percent for 

2013, though samples were not obtained from all four regions 2012. Combining year-classes 

resulted in an overall classification accuracy of 84 percent thus demonstrating the utility of this 

approach. Our results are encouraging yet highlight a need for more research to better evaluate 

the efficacy of vertebral chemistry to study elasmobranch population connectivity. 

Elasmobranch Feeding Ecology 

The current Consolidated Atlantic HMS FMP gives little consideration to ecosystem function 

because there are little quantitative species-specific data on diet, competition, predator-prey 

interactions, and habitat requirements of sharks. Therefore, several studies are currently 

underway describing the diet and foraging ecology, habitat use, and predator-prey interactions of 

elasmobranchs in various communities. 

Cooperative Gulf of Mexico States Shark Pupping and Nursery Survey (GULFSPAN) and 

Tagging Database 

The SEFSC Shark Population Assessment Group manages and coordinates a survey of coastal 

bays and estuaries from Cedar Key, Florida, to Terrebonne Bay, Louisiana. Surveys identify the 

presence or absence of neonate (newborn) and juvenile sharks and attempt to quantify the 

relative importance of each area as it pertains to essential fish habitat (EFH). The Group 

initiated a juvenile shark abundance index survey in 1996. The index is based on random, depthstratified gillnet sets conducted throughout coastal bays and estuaries in coastal areas of the Gulf 

of Mexico from April to October. The species targeted in the index of abundance survey are 

juvenile sharks in the large and small coastal management groups. This index has been used as 

an input to various stock assessment models. A database containing tag and recapture 

information on elasmobranchs tagged by GULFSPAN participants currently includes over 8,000 

tagged animals and 155 recaptured animals from 1993 to present for both the Gulf of Mexico and 

U.S. southeast Atlantic Ocean. This fully searchable database is current through spring 2013 

with hopes to have it online and searchable by all participants in FY 2016. 

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Monitoring the Recovery of Smalltooth Sawfish (Pristis pectinata) 

The smalltooth sawfish was listed as endangered under the ESA in 2003. Smalltooth sawfish are 

the first marine fish and first elasmobranch listed under the ESA. Smalltooth sawfish were once 

common in the Gulf of Mexico and off the southeast coast of the United States. Decades of 

fishing pressure, both commercial and recreational, and habitat loss caused the population to 

decline by up to 95 percent during the second half of the twentieth century. Today, they exist 

primarily in southern Florida. 

The completion of the Smalltooth Sawfish Recovery Plan in early 2009 brought about a new 

phase of research and management for the U.S. population of smalltooth sawfish. Research and 

monitoring priorities identified in the Recovery Plan are now being implemented. Field work is 

underway to gather information on determining critical habitat and monitoring the population. 

This information will evaluate the effectiveness of protective and recovery measures and help 

determine if the population is rebounding or, at the very least, stabilizing. 

One of the high-priority research areas is monitoring of the number of juvenile sawfish in 

various regions throughout Florida to provide a baseline and time series of abundance. One of 

the more important regions for smalltooth sawfish identified in previous research is the section of 

coast from Marco Island to Florida Bay, Florida. This region encompasses the coast of the Ten 

Thousand Islands National Wildlife Refuge and Everglades National Park. Scientists from the 

SEFSC conduct monthly surveys in southwest Florida to capture, collect biological information, 

tag, and then release smalltooth sawfish. Preliminary results indicate that juvenile sawfish 

exhibit a high degree of site fidelity. Genetic identification of recaptured individuals indicates 

that sawfish caught on the same mudflat, for example, are siblings and a single adult female 

sawfish may give birth on that same mudflat year after year. 

Determination of critical habitat and movement and migration corridors for larger juvenile and 

adult sawfish is being undertaken using acoustic tracking, PSAT and SPOT tags. Large sawfish 

generally remained in coastal waters within the region where they were initially tagged, 

travelling an average of 80.2 kilometers from deployment to pop-up location. The shortest 

distance moved was 4.6 kilometers and the greatest 279.1 kilometers, averaging 1.4 kilometers 

day-1 . Seasonal movement rates for females were significantly different with the greatest 

movements in autumn and winter. Smalltooth sawfish spent the majority of their time at shallow 

depths (96 percent of their time at depths less than 10 meters) and warm water temperatures (22– 

28°C). Over short time periods, movements appeared primarily tidal driven with some evidence 

that animals moved into shallow water during the ebbing or flooding tides. Adult sawfish 

sexually segregated seasonally with males found by mangrove-lined canals in the spring and 

females predominantly found in outer parts of the bay. Males migrated from canals starting in 

late May potentially as temperatures increased above 30° C. Some males and females migrated 

north during the summer, while others may have remained within deeper portions of Florida Bay. 

Male sawfish displayed site fidelity to Florida Bay as some individuals were recaptured 1–2 

years after originally being tagged. We hypothesize that mating occurs in Florida Bay based on 

aggregations of mature animals coinciding with the proposed mating period, initial sexual 

segregation of adults followed by some evidence of females moving through areas where males 

show seasonal residency, and a high percentage of animals showing evidence of rostrum inflicted 

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injuries. The combination of methods providing movement data over a range of spatial and 

temporal scales reveals that sub-tropical embayments serve as essential habitat for adult 

smalltooth sawfish. Given sawfish show a degree of site fidelity punctuated by limited 

migratory movements, emphasizes the need for conservation and management of existing coastal 

habitats throughout the species’ range. 

Successful recovery of sawfish populations requires juvenile recruitment success and initiatives 

now strive to include the protection of areas used by juveniles in order to promote survivorship. 

Initial studies have identified sheltered, shallow, mangrove areas as nursery habitat with 

subsequent studies finding warmer water temperatures and variable salinity associated with the 

capture of juvenile sawfish. However, further refinement is required to fully predict the essential 

features smalltooth sawfish require as juveniles. Since 2009, a fisheries-independent gillnet 

survey of smalltooth sawfish abundance has occurred in Everglades National Park, US. 

Variables collected with each sample include environmental characters such as temperature, 

salinity, and dissolved oxygen and, in later years, specific habitat features, such as mangrove 

prop root density. Using a bivariate generalized linear mixed modeling approach, we conducted 

exhaustive screening of all possible variable combinations including two-way interactions to 

construct habitat suitability models for young-of-the year and juvenile smalltooth sawfish. 

Variable selection was determined using a combination of Chi-square tests of significance and 

minimizing the Bayesian information criterion. Regardless of life stage, habitat suitability 

models suggest that salinity, red mangrove prop root and number of pneumatophores on black 

mangroves are the most important factors driving smalltooth sawfish occurrence. Coastal 

development and urbanization have caused mangrove habitats globally to be removed from many 

areas throughout the species’ current range. Given the importance of mangroves to the 

recruitment of juvenile sawfish, adequate protection of remaining areas will be essential for 

recovery of the species. 

Population structure of blacksnose sharks in the western North Atlantic Ocean 

Patterns of population structure and historical genetic demography of blacknose sharks in the 

western North Atlantic Ocean were assessed using variation in nuclearencoded microsatellites 

and sequences of mitochondrial DNA (mtDNA). Significant heterogeneity and/or inferred 

barriers to gene flow, based on microsatellites and/or mtDNA, revealed the occurrence of five 

genetic populations localized to five geographic regions: the southeastern U.S Atlantic coast, the 

eastern Gulf of Mexico, the western Gulf of Mexico, Bay of Campeche in the southern Gulf of 

Mexico and the Bahamas. Pairwise estimates of genetic divergence between sharks in the 

Bahamas and those in all other localities were more than an order of magnitude higher than 

between pairwise comparisons involving the other localities. Demographic modelling indicated 

that sharks in all five regions diverged after the last glacial maximum and, except for the 

Bahamas, experienced post-glacial, population expansion. The patterns of genetic variation also 

suggest that the southern Gulf of Mexico may have served as a glacial refuge and source for the 

expansion. Results of the study demonstrate that barriers to gene flow and historical genetic 

demography contributed to contemporary patterns of population structure in a coastal migratory 

species living in an otherwise continuous marine habitat. The results also indicate that for many 

marine species, failure to properly characterize barriers in terms of levels of contemporary gene 

80
 
 

 

 

 

 

 

 

 

 

 

 

 

flow could in part be due to inferences based solely on equilibrium assumptions. This could lead 

to erroneous conclusions regarding levels of connectivity in species of conservation concern. 

Life History Studies of Elasmobranchs 

Biological samples are obtained through research surveys and cruises, recreational and 

commercial fishermen, and collection by onboard observers on commercial fishing vessels. Age 

and growth rates and other life-history aspects of selected species are processed and analyzed 

following standard methodology. This information is vital as input to population models used to 

predict the productivity of the stocks and to ensure they are harvested at sustainable levels. 

An assessment of the diet and trophic level of Atlantic sharpnose shark Rhizoprionodon 

terraenovae 

A re-assessment of the diet of the Atlantic sharpnose shark was conducted to provide an update 

on their trophic level. Atlantic sharpnose shark primarily consume teleosts, but previously 

unreported loggerhead sea turtles (Caretta caretta) were also found in the diet. Analysis 

suggests that calculated trophic level may depend on diet and geographic area. 

Life history of bonnethead sharks in the western North Atlantic Ocean 

The age, growth and maturity of bonnetheads Sphyrna tiburo inhabiting the estuarine and coastal 

waters of the western North Atlantic Ocean (WNA) from Onslow Bay, North Carolina, south to 

West Palm Beach, Florida, were examined. Vertebrae were collected and aged from 329 females 

and 217 males ranging in size from 262 to 1,043 millimeters and 245 to 825 millimeters fork 

length, LF, respectively. Sex-specific von Bertalanffy growth curves were fitted to length-at-age 

data. Female von Bertalanffy parameters were L∞ =1036 millimeters LF, k =0⋅18, t0= −1⋅64 and 

L0 =272 millimeters LF. Males reached a smaller theoretical asymptotic length and had a higher 

growth coefficient (L∞ =782 millimeters LF, k =0⋅29, t0= −1⋅43 and L0 =266 millimeters LF). 

Maximum observed age was 17⋅9 years for females and 16⋅0 years for males. Annual deposition 

of growth increments was verified by marginal increment analysis and validated for age classes 

2⋅5+ to 10⋅5+ years through recapture of 13 oxytetracycline-injected specimens at liberty in the 

wild for 1–4 years. Length (LF50) and age (A50) at 50 percent maturity were 819 millimeters 

and 6⋅7 years for females, and 618 millimeters and 3⋅9 years for males. Both female and male S. 

tiburo in the WNA had a significantly higher maximum observed age, LF50, A50 and L∞, and a 

significantly lower k and estimated L0 than evident in the Gulf of Mexico (GOM). These 

significant differences in life-history parameters, as well as evidence from tagging and genetic 

studies, suggest that S. tiburo in the WNA and GOM should be considered separate stocks. 

Bonnethead (Sphyrna tiburo) site fidelity 

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To examine the migratory patterns, habitat utilization and residency of bonnethead sharks 

(Sphyrna tiburo) in estuarine systems within coastal South Carolina, a tag-recapture experiment 

was conducted from 1998 to 2012 during which 2,300 individuals were tagged. To assess the 

intra and inter-annual movements of tagged sharks, six estuaries within state waters were 

monitored using multiple gear types in addition to the cooperative efforts of recreational anglers 

throughout the southeastern United States. 

Over the course of the experiment 177 

bonnetheads were recaptured after 3 days to 

8.9 years at liberty, representing a recapture 

rate of approximately 8 percent. All 

bonnetheads were recaptured within the same 

estuary where they were originally tagged on 

intra and/or inter-annual scales, with the 

exception of six individuals, which were 

recaptured during migratory periods (i.e. late 

fall, winter and spring) in coastalwaters off 

Figure 5.6: Scalloped hammerhead 

captured in the Gulf of Mexico during a 

bottom longline survey. 

Source: NMFS SEFSC 

Florida, Georgia, North Carolina, and South 

Carolina. On 23 occasions, cohesion was 

demonstrated by groups ranging in size from 

2 to 5 individuals that were tagged together 

and recaptured together, with times at liberty 

ranging from12 days to 3.6 years. 

Additionally, 13 individuals were recaptured multiple times with times at liberty ranging from 12 

days to 8.9 years; all individuals were recaptured in the same estuary where they were initially 

tagged. We hypothesize that bonnetheads are using South Carolina's estuaries as summer feeding 

grounds due to the relatively high abundance of blue crabs (Callinectes sapidus), including 

ovigerous females during spring and summer months, and the location of these ephemeral yet 

predictable feeding areas is socially transmitted to relatively young, naïve sharks by experienced, 

elder individuals. 

Cooperative Research—Uruguay-U.S. pelagic shark research project 

The SEFSC continues to collaborate with Uruguay’s fisheries agency (DINARA) to advance 

knowledge on movement patterns, habitat use, the productivity and susceptibility of pelagic 

sharks to longline fisheries in the western South Atlantic Ocean; aspects of which are largely 

unknown for pelagic sharks in the southern hemisphere. To that end, 11 satellite tags have been 

deployed on blue sharks to date. Tags that are providing real time data, along with data for 

Ecological Risk Assessments are used as outreach to promote the collaboration between NOAA 

and DINARA. 

Shark Assessment Research Surveys 

The SEFSC has conducted bottom longline surveys in the Gulf of Mexico (see Figure 6.6), 

Caribbean, and Southern North Atlantic since 1995 (32 surveys have been completed through 

2014). The primary objective is assessment of the distribution and abundance of large and small 

coastal sharks across their known ranges in order to develop a time series for trend analysis. The 

surveys, which are conducted at depths between 9 and 366 fathoms, were designed specifically 

for stock assessment purposes. The bottom longline surveys are the only long-term, nearly 

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stock-wide, fishery-independent surveys of western North Atlantic Ocean sharks conducted in 

U.S. waters and neighboring waters. Recently, survey effort has been extended into depths 

shallower than 5 fathoms (9.1 meters) to examine seasonality and abundance of sharks in inshore 

waters of the northern Gulf of Mexico and to determine what species and size classes are outside 

of the range of the sampling regime of the long-term survey. This work is being done in 

cooperation with SEAMAP partner institutions. For all surveys, ancillary objectives are to 

collect biological and environmental data, and to tag and release sharks. The surveys continue to 

address expanding fisheries management requirements for both elasmobranchs and teleosts. 

Northeast Fisheries Science Center (NEFSC) 

Fishery Independent Surveys and Recreational Monitoring of Coastal and Pelagic Sharks 

Fishery Independent Coastal Shark Bottom Longline Survey 

The fishery independent survey of Atlantic large 

and small coastal sharks is conducted biannually in U.S. waters, depending on funding. 

Its primary objective is to conduct a 

standardized, systematic survey of the shark 

populations off the U.S. Atlantic coast to 

provide unbiased indices of relative abundance 

for species inhabiting the waters from Florida to 

the Mid-Atlantic (see Figure 6.7). This survey 

also provides an opportunity to tag sharks with 

conventional and electronic tags as part of the 

NEFSC Cooperative Shark Tagging Program, to 

inject with oxytetracycline for age validation 

studies, and to collect biological samples and 

determine life history characteristics (age, 

growth, reproductive biology, trophic ecology, 

etc.). In addition, the collection of 

morphometric information provides data needed to calculate length to length and length to 

weight conversions. The time series of abundance indices from this survey are critical to the 

evaluation of coastal Atlantic shark species. Results from the 2012 survey included 1,845 fish 

(1,831 sharks) representing 16 species. Sharks represented 99 percent of the total catch of which 

sandbar sharks were the most common, followed by dusky and tiger sharks. As part of this 

survey, bottom longline sets were conducted in the closed area off North Carolina. These results 

represent the highest catches of sharks from any previous survey to date. Staff analyzed the 

dusky shark catches from this survey through 2012 to update the index of abundance for use in 

the Status Review for the northwest Atlantic Dusky Shark in response to petitions to list the 

species under the Endangered Species Act (McCandless et al. 2014a). Also in 2014, staff 

prepared the contract for the fishing vessel in support of the next survey scheduled for spring of 

2015. 

Fishery Independent Pelagic Shark Longline Survey 

NMFS and its predecessor agencies, the Bureau of Commercial Fisheries and the Bureau of 

Sport Fish and Wildlife, conducted periodic longline surveys for swordfish, tunas, and sharks off 

Figure 5.7. Releasing a sandbar shark during the 

NEFSC Coastal Shark Bottom Longline Survey. 

Source: L.J. Natanson / NMFS photo. 

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the east coast of the United States starting in the early 1950’s. Surveys first targeted tunas and 

swordfish along the edge of the continental shelf, and subsequently focused on pelagic and 

coastal sharks over a variety of depths, including inshore bays and estuaries. The last large-scale 

pelagic fishing trip was conducted in 1985; however, the NEFSC Narragansett Laboratory 

completed a pilot survey in the spring of 2006 and conducted additional pelagic sets in 2007. 

The goal of this research is to initiate a standardized fishery independent pelagic shark survey in 

order to conduct research and monitor shark abundance and distribution. 

Juvenile Shark Survey for Monitoring and Assessing Delaware Bay Sandbar Sharks 

(Carcharhinus plumbeus) 

The juvenile sandbar shark population in Delaware Bay is surveyed by NEFSC staff as part of 

the Cooperative Atlantic States Shark Pupping and Nursery (COASTSPAN) program. A random 

stratified longline sampling plan, based on depth and geographic location, was developed in 

2001 to assess and monitor the juvenile sandbar shark population during the nursery season. In 

2014, a total of 473 sandbar sharks were caught with 95 percent of these sharks released with 

conventional tags. The mark-recapture data from this study has been used to examine the 

temporal and spatial relative abundance and distribution of sandbar sharks in Delaware Bay, and 

the juvenile index of abundance from this standardized survey has been used as an input into 

various stock assessment models in the SEDAR process. During the most recent SEDAR for 

sandbar sharks, catch per unit effort (CPUE) in number of sharks per 50-hook set per hour was 

used to examine the relative abundance of young of the year, age 1+, and total juvenile sandbar 

sharks between the summer nursery seasons in Delaware Bay from 2001 to 2009 (McCandless, 

2010). All three juvenile sandbar shark time series showed stability in relative abundance from 

2001 to 2005 with only a brief decrease in abundance in 2002, which may be attributed to a large 

storm (associated with a hurricane offshore) that passed through the Bay that year. There was a 

subsequent decreasing trend from 2005 to 2008 that ends with an increase in relative abundance 

in 2009. 

Delaware Bay Sand Tiger (Carcharias taurus) Survey 

A survey, initiated in 2006 targeting the sand tiger shark 

for identifying Essential Fish Habitat (EFH) and for 

future stock assessment purposes, continued in 2014 

(Figure 6.8). This study incorporates historical NEFSC 

sampling stations to allow for comparison between 

historic and current abundances. This survey is also used 

to monitor the Delaware Bay sand tiger population and to 

evaluate long-term changes in abundance and size 

composition. In 2014, a total of 45 sand tigers were Figure 5.8. Measuring a sand tiger during 

caught and released and 93 percent of these sharks were the NEFSC Delaware Bay Sand Tiger 

Survey. tagged with conventional tags bringing the total since the Source: Corey Eddy / NMFS photo. beginning of the survey to 283 sand tigers. 

Collection of Recreational Shark Fishing Data and Samples 

Historically, species-specific landings data from recreational fisheries is lacking for sharks. In 

an effort to augment these data, the NEFSC has been attending recreational shark tournaments 

continuously since 1961 collecting data on species, sex, and size composition from individual 

84
 
 

 

 

 

 

 

events; in some cases, for nearly 50 years. In addition, these tournaments provide a source of 

samples for pelagic and some coastal sharks to aid in our biological research. Analysis of these 

tournament landings data was initiated by creating a database of historic information (1961­

2014) and producing preliminary summaries of some long-term tournaments. These analyses 

have been used to provide advice on future minimum size catch requirements for these 

tournaments. The collection and analysis of these data are critical for input into species and age 

specific population and demographic models for shark management. In 2014, biological samples 

for life history studies and catch and morphometric data for more than 150 pelagic sharks were 

collected at nine recreational fishing tournaments in the northeastern United States. Participation 

at recreational shark tournaments and the resultant information is very valuable as a monitoring 

tool to provide long-term data that can detect trends in species and size composition, provide 

critical specimens and tissue for life history and genetic studies, provide outreach opportunities 

for recreational fishermen and the public, and finally, to provide additional information on 

movements that complement the NMFS Cooperative Shark Tagging Program (CSTP). 

Additionally, analysis of the white shark catches recorded from five long-term tournaments 

sampled by the NEFSC were used to develop a relative index of abundance for use in a recent 

publication on historical trends in abundance (Curtis et al. 2014). 

In 2014, NOAA Fisheries staff worked with a variety of partners (Concerned Citizens of 

Montauk, Montauk Chamber of Commerce, researchers from MADMF, Mote, OCEARCH, 

recreational sport fishermen, charter boat captains, marina owner, and the Guy Harvey Ocean 

Foundation) for an all-release, satellite tag shark tournament in Montauk, LI, NY called ‘Shark’s 

Eye.’ This is the second year for this only satellite tag, all-release shark tournament held in the 

Northeast US; rules required the mandatory use of circle hooks, heavy tackle and safe handling 

practices. Results from the second year included six electronic SPOT tags that were put on two 

tiger sharks, three shortfin makos and one blue shark, as well as numerous conventional tags on 

shortfin makos and blue sharks. Location data from the spot tags were made available on the 

OCEARCH website. Additionally, there was a two-day public outreach event where much 

information was given out on NOAA Fisheries research. 

NEFSC Historical Longline Survey Database 

The NEFSC recovered the shark species catch per set data from the exploratory shark longline 

surveys conducted by the Sandy Hook and Narragansett Laboratories from 1961 to 1991. In 

addition to the fishery-independent surveys conducted by the NEFSC, scientific staff has been 

working with the University of North Carolina (UNC) to electronically recover the data from an 

ongoing coastal shark survey in Onslow Bay that began in 1972. These surveys provide a 

valuable historical perspective for evaluating the stock status of Atlantic sharks. This data 

recovery process is part of a larger, systematic effort to electronically recover and archive 

historical longline surveys and biological observations of large marine predators (swordfish, 

sharks, tunas, and billfishes) in the North Atlantic. When completed, these efforts will include 

reconstructing the historic catch, size composition, and biological sampling data into a 

standardized format for time series analysis of CPUE and size. Standardized indices of 

abundance developed for sharks caught during these longline surveys have been and will 

continue to be used in stock assessments as part of the SEDAR process. Abundance indices 

were summarized for sandbar and dusky sharks caught during the NEFSC exploratory longline 

surveys (McCandless and Hoey 2010) and for smooth dogfish, Atlantic sharpnose, blacknose, 

85
 
 

 

 

sandbar, and dusky sharks caught during the UNC shark survey (Schwartz et al. 2010, Schwartz 

et al. 2013, McCandless et al 2014d). Additionally, white shark catches from the NEFSC 

exploratory longline surveys were used to develop an index of relative abundance for a recent 

publication on historical trends in abundance (Curtis et al. 2014). Work on the recovery of 

environmental data for both the NEFSC and the UNC time series, as well as the associated 

individual shark data, is ongoing to further refine these indices and to develop indices of 

abundance for other shark species, and for future use in shark EFH designations. Analyzing 

catch rates according to differences in time, space, or methods provide an opportunity to better 

understand seasonal distribution patterns and relative vulnerability of various species to different 

fishing practices. 

Southeast Data, Assessment, and Review (SEDAR) Process 

NEFSC Staff participated in the SEDAR 39 Data Workshop for the assessment of the Atlantic 

smooth dogfish population and the Gulf of Mexico smoothhound complex. A working paper for 

Atlantic smooth dogfish was presented during the workshop summarizing mark/recapture data 

from the Cooperative Shark Tagging Program (Kohler et al. 2014). In addition, five working 

papers detailing multiple indices of abundance for Atlantic smooth dogfish were developed using 

longline survey data from the Cooperative Atlantic States Shark Pupping and Nursery 

(COASTSPAN) survey (McCandless 2014b), the South Carolina Department of Natural 

Resources (McCandless and Frazier 2014), and the University of North Carolina (McCandless et 

al. 2014d); as well as, gillnet survey data from the North Carolina Division of Marine Fisheries 

(McCandless et al 2014c) and gillnet observer data from the Northeast Fisheries Observer 

Program (McCandless and Mello 2014). Multiple indices of abundance were also developed for 

six working papers using trawl survey data from the University of Rhode Island (McCandless 

2014c), Rhode Island Department of Environmental Management (McCandless and Olsewski 

2014), Connecticut Department of Energy and Environmental Protection (McCandless and 

Gottschall 2014), New York State Department of Environmental Conservation (McCandless and 

Grahn 2014), New Jersey Division of Fish and Wildlife (McCandless et al. 2014b), and 

Delaware Division of Fish and Wildlife (McCandless and Greco 2014). Additionally, staff cochaired the Indices Working Group for the SEDAR Data Workshop and produced Indices 

Working Group Reports summarizing working group recommendations for both the Atlantic 

smooth dogfish and smoothhound complex. Staff also developed a working paper for the 

SEDAR Assessment Workshop detailing the hierarchical analysis of the recommended indices of 

abundance to create a single index of abundance to use in sensitivity analyses during the SEDAR 

Assessment Workshop for both the Atlantic smooth dogfish and the Gulf of Mexico 

smoothhound complex (McCandless 2014a). 

Deepwater Horizon C252 Pelagic Fish Sampling 

Staff biologists participated in a pelagic longline cruise inside and adjacent to the area closed to 

fishing due to the Deepwater Horizon C252 oil spill. The objectives of this cruise were to collect 

highly migratory fish for food quality studies in the vicinity of the oil spill resulting from the 

sinking of the Deepwater Horizon oil platform; to monitor the distribution and abundance of 

highly migratory species in the Gulf of Mexico with reference to the oil sheen; and to collect 

salinity and temperature profile data and water samples for hydrocarbon analysis. All 

commercially and recreationally valuable and legal sized pelagics were saved for seafood 

sampling. 

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Endangered Species Act 

NEFSC staff contributed to and led the Status Review Team for the Northwest Atlantic dusky 

shark, in response to a positive 90-day finding indicating that petitions presented substantial 

information that listing under the Endangered Species Act as threatened or endangered may be 

warranted for this population. Multiple analyses were produced and data were summarize from 

all available resources for use by the Status Review Team to produce a comprehensive review 

and extinction risk analysis for the Northwest Atlantic dusky shark population. NEFSC staff 

provided NMFS Protected Resources with a Status Review Report (McCandless et al. 2014a) 

indicating that the Northwest Atlantic dusky shark distinct population segment was at low risk 

for extinction and this report was released to the public in December 2014 with a negative 12­

month finding indicating that listing under the Endangered Species Act was determined to be 

unwarranted. 

Pelagic Nursery Grounds 

Pelagic shark biology, movements, and abundance studies continued in 2014 with further 

investigations of pelagic nursery grounds in conjunction 

with the high seas commercial longline fleet. This 

collaborative work offers a unique opportunity to sample 

and tag blue sharks (Prionace glauca) and shortfin makos 

(Isurus oxyrinchus) in a potential nursery area on the 

Grand Banks, to collect length-frequency data and 

biological samples, and to conduct conventional and 

electronic tagging of these species (see Figure 6.9). In 

2007 and 2008, two real-time satellite (SPOT) tags and five 

pop-up satellite archival tags (PSAT) tags were deployed 

on shortfin makos and one PSAT tag was deployed on a 

blue shark. A total of 500 blue sharks have been double 

tagged using two different tag types to help evaluate tagshedding rates used in sensitivity analyses for population estimates and to calculate fishing 

mortality and movement rates for this pelagic shark species. In 2014, an additional 220 sharks 

were tagged bringing the total to over 3,600 with over 280 recaptured. These fish were primarily 

blue sharks that were recovered by commercial fishermen working in the mid-Atlantic Ocean. 

This research was featured as part of the Discovery Channel’s ‘Swords: Life on the Line,’ a 

series documenting the lives of commercial longline fishermen. 

Cooperative Atlantic States Shark Pupping and Nursery (COASTSPAN) Program 

The NEFSC manages and coordinates this 

program, which surveys Atlantic coastal waters 

from Florida to Massachusetts and in the U.S. 

Virgin Islands (USVI) by conducting cooperative, 

comprehensive, and standardized investigations of 

coastal shark nursery habitat. COASTSPAN 

surveys are used to describe habitat preferences, Figure 5.10. Tagging a juvenile sandbar shark 

and to determine the relative abundance, during the NEFSC COASTSPAN Program Survey. 

Source: W. David McElroy / NMFS photo. distribution, and migration of shark species 

Figure 5.9. Shortfin mako brought aboard 

during the NEFSC Pelagic Nursery Ground 

cruise. 

Source: Lisa Natanson / NMFS photo. 

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through longline and gillnet sampling and mark-recapture data (see Figure 6.10). In 2014, our 

COASTSPAN participants were the Massachusetts Division of Marine Fisheries (MDMF), 

Stony Brook University, Virginia Institute of Marine Science, North Carolina Division of Marine 

Fisheries, South Carolina Department of Natural Resources, Georgia Department of Natural 

Resources, and the University of North Florida. MDMF staff also conducts a survey in the U.S. 

Virgin Islands using COASTSPAN gear and methods. The NEFSC staff conducts the survey in 

Narragansett and Delaware Bays. Data from COASTSPAN surveys are used to update and 

refine EFH designations for multiple life stages of managed coastal shark species. Standardized 

indices of abundance from COASTPAN surveys are used in the stock assessments for large and 

small coastal sharks. In 2014, data from these COASTSPAN surveys were provided to NMFS 

Highly Migratory Species Management Division for use in a 5-year review of Essential Fish 

Habitat designations for all managed shark species. Additionally, data from the COASTSPAN 

survey conducted in Delaware Bay were used to produce indices of abundance for Atlantic 

smooth dogfish that were presented in a working paper at the SEDAR Data Workshop in May 

2014 (McCandless 2014b). 

In collaboration with MDMF and NMFS (Galveston, TX; Silver Spring, MD), a study was 

initiated in 2006 to investigate the spatial and temporal use of nursery habitat by neonatal 

blacktip (Carcharhinus limbatus) and lemon (Negaprion brevirostris) sharks in Fish Bay and 

Coral Bay on the island of St John, United States Virgin Islands using both active and passive 

acoustic telemetry. Acoustic transmitters were surgically implanted in blacktip and lemon sharks 

and their movements are currently being monitored using passive acoustic telemetry to determine 

site fidelity, residency and migration patterns. Only 8 percent of lemon sharks and14.5 percent 

of blacktip sharks exhibited long-term residency (> 180 days) within the bays while most of the 

sharks moved out by the fall and early winter months. Although several sharks were detected 

outside of Fish and Coral bays and a few (five blacktips) traveled between the two bays, each 

species exhibited strong site attachment to the bay in which they were tagged. Efforts to 

examine intra and inter-specific patterns of habitat use as they relate to the biotic and abiotic 

characteristics of each embayment are ongoing. A presentation summarizing these results 

(Legare et al. 2011) was given at the 2011 American Elasmobranch Society Meeting. 

Habitat Utilization and Essential Fish Habitat of Sand Tiger Sharks 

Funding was received in 2006 through the NOAA Living Marine Resources Cooperative Science 

Center to support a multi-year cooperative research project with staff from Delaware State 

University and the University of Rhode Island on habitat use, depth selection, and the timing of 

residency for sand tigers in Delaware Bay. Sand tigers were implanted with standard acoustic or 

depth-sensing transmitters to monitor their movements and habitat use of Delaware Bay during 

the summer months. Sand tiger movements continue to be monitored using passive acoustic 

telemetry. 

Funding was received through the NOAA NMFS Species of Concern Internal Grant Program to 

study the regional movements, habitat use, and site fidelity of sand tigers off the US east coast 

using satellite telemetry. PSATs were deployed on seven sand tigers; five caught in 

Massachusetts state waters and two caught in Rhode Island state waters. Despite their small size 

and young age, the available tagging data revealed that juvenile sand tigers undergo extensive 

seasonal coastal migrations along the US east coast. Individual tagged sharks were observed to 

88
 
 

 

 

 

 

 

 

 

 

 

travel distances of approximately2,500 kilometers over a 4 to 5 month period from October to 

February; migrating from as far north as northern New England south to central Florida before 

returning north the following spring (April to May). In general, two distinct migratory periods 

(northward: April to June; southward: October to January) were apparent throughout a calendar 

year, when sharks moved along the coastline (in less than 80 meters of water) between summer 

and winter habitat. Depth data obtained in this study suggest that juvenile sand tigers follow 

coastal bathymetric contours throughout their extensive coastal migration. Temperature 

preferences exhibited by juvenile sand tigers in this study were very similar to those reported for 

sub-adult and adult sand tigers throughout their range. Off the East Coast of the US, juvenile 

sand tigers experienced temperatures ranging from 9.8 to 24.2 ̊C, spending the majority of their 

time (91 to 99 percent) between 10.0 and 20.0 ̊C. The data from this study was contributed to a 

larger study conducted by our grant partner from Massachusetts Division of Marine Fisheries 

and the combined results led a publication on movement patterns of juvenile sand tigers along 

the east coast of the United States (Kneebone et al. 2014). 

Essential Fish Habitat (EFH) Designations 

NEFSC staff participates on a working group with others from the NMFS HMS Management 

Division and SEFSC to update and refine the EFH designations for managed shark species. This 

process was ongoing in 2014 and entailed providing summaries from COASTSPAN surveys and 

the CSTP databases to update EFH for coastal shark species and information for the EFH section 

of the annual Stock Assessment and Fisheries Evaluation Report. Additionally, staff provided 

updates to previously supplied data and results from ongoing research for the NMFS HMS 

Management Division 5-year review of Essential Fish Habitat Designations for all managed 

shark species, and provided reviews of the draft document. 

Elasmobranch Life History Studies 

NEFSC life history studies are conducted on Atlantic species of elasmobranchs to address 

priority knowledge gaps and focus on species with declines and management issues. Biological 

samples are obtained on research surveys and cruises, on commercial vessels, at recreational 

fishing tournaments, and opportunistically from strandings. In recent years, studies have 

concentrated on a complete life history for a species to obtain a total picture for management. 

This comprehensive life history approach encompasses studies 

on age and growth rates and validation, diet and trophic 

ecology, and reproductive biology essential to estimate 

parameters for demographic, fisheries, and ecosystem models. 

Atlantic Blue Shark (Prionace glauca) and Shortfin Mako 

(Isurus oxyrinchus) Life History and Assessment Studies 

Collaborative programs to examine the biology and population 

dynamics of the blue shark and shortfin mako in the North 

Atlantic are ongoing. Fisheries-independent published research 

on blue shark demographics has allowed for the construction of 

an age-structured population model. This model confirms the 

importance of juvenile survival for population growth. In 

addition, a risk analysis is proposed as a supplement to the dataFigure 5.11. Blue shark ready to be 

tagged and released. 

Source: Lisa J. Natanson / NMFS 

photo. 

limited stock assessment to better evaluate the probability that a 

89
 
 

 

 

 

 

 

 

 

 

 

 

given management strategy will put the population at risk of decline. 

Shortfin mako survival was estimated from NMFS Cooperative Shark Tagging Program markrecapture data. Estimates of survival (0.705–0.873 per year) were generated with the computer 

software MARK by analyzing tagged (n=6,309) and recaptured (n=730) animals. An estimate of 

survival is a key variable for stock assessments and subsequent demographic analyses, and is 

crucial when it comes to directly managing exploited or commercially viable species. 

From samples collected from recreational fishing tournaments and research cruises, a genetic 

approach for identifying pelagic shark tissues was streamlined by researchers at NOVA 

Southeastern University. The result is a rapid, accurate, and relatively inexpensive genetic assay 

for identifying tissues and body parts from the shortfin mako, as well silky, dusky, sandbar, and 

longfin mako shark species. 

Regional sizes, sex ratios, maturation, and movement patterns were analyzed for 91,450 blue 

sharks tagged by CSTP in the North Atlantic Ocean from 1962-2000. Of these, 5,410 were 

recaptured for an overall recapture rate of 5.9 percent. Blue sharks made frequent trans-Atlantic 

crossings from the western to eastern regions, and were shown to move between most areas; the 

mean distance traveled was 857 kilometers, and the mean time at liberty between tagging and 

recapture was 0.9 year. North Atlantic blue sharks are believed to constitute a single stock, and a 

better understanding of their complex movements, life-history strategies, and population 

structure is needed to develop informed management of this open ocean species. 

Utilizing this blue shark tag-recovery data from the NMFS CSTP (1965–2004), a spatially 

structured tagging model was used to estimate blue shark movement and fishing mortality rates 

in the North Atlantic Ocean (Aires-da-Silva et al. 2009). Four major geographical regions (two 

on each side of the ocean) were assumed with the blue shark fishing mortality rates (F) found to 

be heterogeneous across the four regions. While the estimates of F obtained for the western 

North Atlantic Ocean were historically lower than 0.1 year–1, the F estimates over the most 

recent decade (1990s) in the eastern side of the ocean are rapidly approaching 0.2 year–1 . 

Because of the particular life-history of the blue shark, these results suggest careful monitoring 

of the fishery as the juvenile and pregnant female segments of the stock are highly vulnerable to 

exploitation in the eastern North Atlantic Ocean. 

The blue shark has been subject to bycatch fishing mortality for almost a half-century and has 

even become the target species in pelagic longline fisheries in the North Atlantic Ocean. 

Nevertheless, stock status is ambiguous and improved input data are needed for stock 

assessments. It is particularly important to obtain reliable indices of abundance because of the 

uncertainty in estimates of bycatch. An index of relative abundance was developed for western 

North Atlantic blue sharks, starting from the mid-1950s, when industrial pelagic longline tuna 

fisheries began. Longline catch and effort records from recent observer programs (1980–1990s) 

were linked with longline survey records from both historical archives and recent cruises (1950– 

1990s). Generalized linear models were used to remove the effects of diverse fishing target 

practices, and geographical and seasonal variability that affect blue shark catch rates. The 

analysis revealed a decline in blue shark relative abundance of approximately 30 percent in the 

western North Atlantic from 1957 to 2000. The magnitude of this relative abundance decline 

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was less than other recently published estimates and seems reasonable in light of the high 

productivity of the blue shark revealed by life-history studies and preliminary stock assessments. 

Biology of the Spiny Dogfish (Squalus acanthias) 

The NEFSC Cooperative Research and Apex Predators Program began tagging spiny dogfish in 

the Gulf of Maine, Southern New England, and Georges Bank regions in 2011. This project 

aims to answer long-standing questions about stock structure, movement patterns, and life 

history to update and improve spiny dogfish stock assessments. Over a two-year period, dogfish 

were tagged during winter and summer using three commercial vessels. In 2012, an additional 

18,570 spiny dogfish were tagged, bringing the total tagged to 34,604 for the two year project. 

Of the total tagged, 891 have been recaptured through 2014. Some tagged dogfish were injected 

with oxytetracycline (OTC) for an age validation study. As of 2014, 150 fish that were OTC 

injected have been recaptured and returned to the NEFSC for age validation. 

A new initiative was launched to determine the seasonality of pupping and gestation period of 

female spiny dogfish in Southern New England. Many populations of spiny dogfish are known 

to have a two-year gestation period, however, this has never been comprehensively studied in the 

western North Atlantic. The primary purpose of this study is to determine the gestation period. 

Additional information on seasonality of mating and pupping and size at birth will also be 

obtained. 30 samples of mature females will be obtained and dissected each month and sampling 

will continue for two years. By the end of 2014, a year and a half of sampling was 

accomplished; all months except October were sampled for the first year. 

Biology of the White Shark (Carcharodon carcharias) 

The white shark is well documented in the western North Atlantic (WNA) from Newfoundland 

to the Gulf of Mexico, including the Bahamas and parts of the Caribbean. However, the species 

is relatively elusive in the WNA and efforts to study its life history and ecology have been 

hampered by the inability of researchers to predictably encounter these sharks. NEFSC staff in 

cooperation with staff from Greater Atlantic Regional Fisheries Office, Southeast Fisheries 

Science Center, Massachusetts Division of Marine Fisheries and the Florida Museum of Natural 

History published a study on white sharks in the Northwest Atlantic that provides an optimistic 

outlook for their recovery (Curtis et al. 2014). This study built upon previously published data 

combined with recent unpublished records to present a synthesis of 649 confirmed white shark 

records compiled over a 210-year period (1800-2010) and is the largest white shark dataset yet 

compiled for the Northwest Atlantic. Descriptive statistics and GIS analyses were used to 

quantify the seasonal distribution and habitat use of various subcomponents of the population. 

Relative indices of abundance from historical NEFSC surveys, NEFSC tournament data, the 

observer program for the directed shark longline fishery, and visual records of white sharks in 

New England waters were analyzed to determine temporal trends of white shark abundance in 

the Northwest Atlantic. 

Researchers from Stony Brook University, Field Museum of Chicago, Nova Southeastern 

University, and NEFSC are currently employing a multi-analytical approach to test the 

hypothesis that northwest Atlantic white sharks have experienced a recent loss of genetic 

diversity due to a population bottleneck. Results show that contemporary northwest Atlantic 

white sharks are genetically distinct from other populations and comprise a demographically 

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distinct unit. Ongoing work includes attempting to reconstruct the genetic diversity of white 

sharks in the 1960s and 1970s using DNA recovered from archived vertebrae. Historical genetic 

diversity will be directly compared to contemporary genetic diversity in this study, which could 

serve as a model for similar studies of other elasmobranchs. A manuscript for this study was 

submitted for publication in the Journal of Heredity in 2014. 

Vertebrae for age and growth have been collected by members of the Apex Predators Program 

since 1963. Since they are a prohibited species, new samples are not likely to be obtained in 

sufficient quantity and thus in 2011 an age study was undertaken with the archived samples in 

conjunction with MDMF. Vertebrae from 105 samples were processed and band pairs were 

counted. Preliminary data indicated higher counts than previously obtained for white sharks in 

other parts of the world. To validate these counts samples from five specimens were processed 

for bomb carbon analysis in conjunction with researchers at WHOI. In all but one case, these 

validated our age estimates. In the last case, the bomb carbon indicated a significant 

underestimation using band pair counts (Hamady et al. 2014). Age estimates were up to 40 years 

old for the largest female, fork length (FL): 526 centimeters, and 73 years old for the largest 

male (FL: 493 centimeter). These results dramatically extend the maximum age and longevity of 

white sharks compared to earlier studies, and hint at possible sexual dimorphism in growth rates. 

Using the validated work as a basis to age the species, the ageing work was completed in 2014 

and a manuscript was submitted for publication in Marine and Freshwater Research. 

Biology of the Thresher Shark (Alopias vulpinus) 

Life history studies of the thresher shark in the western North Atlantic continued with published 

accounts of reproductive and age parameters. Reproductive organs from 130 males and 256 

females were examined to describe the reproductive characteristics and determine size at 

maturity and reproductive seasonality for the species in the western North Atlantic Ocean 

(Natanson and Gervelis 2013). Males ranged in size from 78 to 237 centimeters FL and females 

ranged from 62 to 263 centimeters FL. The onset of maturity in males was best described by an 

inflection in the relationship of clasper length to FL in combination with the degree of clasper 

calcification. Males matured between 181 and 198 centimeters FL, and estimated median size at 

maturity was 188 centimeters FL. In females, changes in the relationship between ovary and 

uterus length and width with FL were used to estimate the size at maturity. Females matured 

between 208 and 224 centimeters FL; the estimated median size at maturity was 216 centimeters 

FL. Litter sizes averaged 3.7 young. The period of parturition is protracted, spanning late spring 

to late summer (May–August). As in other Lamniformes, young are nourished through oophagy. 

The proportion of mature females in the resting, pregnant, and postpartum stages provides 

evidence that indicates that the common thresher shark does not reproduce annually. 

Age and growth estimates were generated using vertebral centra from 173 females, 135 males, 

ranging in size from 56 to 264 centimeters fork length (Gervelis and Natanson 2013). Assuming 

that vertebral band pairs were deposited annually, ages were estimated up to 22 years (228 

centimeters FL) for males and 24 years (244 centimeters FL) for females. The growth of both 

sexes was similar until approximately age 8 (185 centimeters FL), after which male growth 

slowed. The growth of females slowed at a later age (approximately age 12) than that of males. 

Relative goodness of fit for all candidate models supported the separate modeling of sexes. For 

males, von Bertalanffy growth parameters generated from the vertebral data using a set size at 

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birth (81 centimeters FL) provided the best fit for the band counts (asymptotic length [L∞] = 

225.4 centimeters FL; growth coefficient [k] = 0.17). For females, the standard three-parameter 

von Bertalanffy growth model provided the best fit to the band counts (L∞ = 274.5 centimeters 

FL; k =0.09; theoretical age at a length of zero [t0] = −4.82). These are the first growth 

parameters generated for common thresher sharks in the WNA and can be used to make 

informed decisions for the management of this species. In 2013, a study on bomb carbon 

validation was initiated. Samples from two specimens were processed for bomb carbon analysis 

in conjunction with researchers at WHOI. In 2014, the results were obtained and used to re-age 

the common thresher shark. A draft manuscript detailing the results was produced for future 

publication. 

Biology of the Galapagos Shark (Carcharhinus galapagensis) 

The Galapagos shark is distributed worldwide in warm, temperate waters and is known to prefer 

oceanic islands. As such, it is the most common species in Bermuda, where commercial 

fishermen land approximately 200 sharks each year, primarily for their liver oil or as bait in 

lobster traps. Despite its ubiquitous presence, Bermuda's Department of Environmental 

Protection has only limited regulations in place to manage this species. This study was begun to 

investigate the life history and ecological role of these sharks. Size-at-maturity is being 

investigated by examining the reproductive system of sharks collected from landings of 

commercial fishermen. Size-at-age and age-at-maturity estimates will be derived from band 

pairs in the vertebral centra of these sharks. Elements of feeding ecology, such as trophic 

position and diet shifts, are being investigated via stable isotope analysis of muscle, liver, and 

vertebrae with stomach contents analysis to reinforce these results. This study is being done in 

conjunction with staff from the University of Massachusetts and Massachusetts Division of 

Marine Fisheries. A presentation summarizing these results (Eddy et al. 2011) was given at the 

2011 American Elasmobranch Society Meeting. 

Biology of the Atlantic Torpedo (Torpedo nobiliana) 

A Master’s Thesis was completed on the biology of the Atlantic torpedo (Mataronas 2010). The 

Life History of Torpedo cf. nobiliana Caught off the Coast of Southern New England will be the 

basis for a future publication. This research is ongoing due to a lack of large females for 

reproductive analysis. Samples for age and growth, reproduction, and food habits were obtained 

from the bycatch of bottom trawl, trap net and gillnet fisheries operating primarily out of Pt. 

Judith, Rhode Island, USA. Males mature between 79 and 86 centimeters TL (50 percent 

maturity was estimated to be 83.6 centimeters TL). Females mature between 113 and 123 

centimeters TL (50 percent maturity was estimated to be 120.9 centimeters TL). The fecundity 

appears to be low, although it is higher than other torpedinid species, probably due to it being the 

largest of the torpedo rays. Seasonality in the reproductive cycle could not be defined due to the 

inability to obtain rays during all months of the year. However, based on the observed 

reproductive condition of the females, data support a biennial reproductive cycle, with a fall 

mating season and parturition occurring the following spring. Size at birth was estimated to be 

20-21 centimeters TL. The strong relationship of vertebral radius to total length suggests that 

vertebrae should be a useful ageing structure for this species. However, vertebral banding 

patterns vary widely among individuals; and thus, ageing has not been completed due to the 

inability to define a working criterion for the identification of band pairs. Work with researchers 

at other institutions is ongoing to determine if it is possible to develop a criterion for band 

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identification. There are approximately 21 validated species in the genus Torpedo, of which only 

the Atlantic torpedo, Torpedo nobiliana, is believed to be found in the Northwest Atlantic 

Ocean. The torpedo rays caught off New England were originally named T. occidentalis and 

were later synonymized as a junior synonymy of a Mediterranean species, Torpedo nobiliana. 

As a result of this study, the population of torpedo rays off the coast of Rhode Island is being 

more closely examined to determine if the species is actually distinct and should revert to the 

name T. occidentalis. Currently, an effort is being made to obtain samples from the eastern 

North Atlantic to compare with the samples from this study to validate the species. 

Biology of the Smooth Skate (Malacoraja senta) 

The smooth skate is one of the smallest (less than 70 centimeters TL; less than 2.0 kilograms 

wet weight) species of skate endemic to the western North Atlantic and has a relatively broad 

geographic distribution, ranging from Newfoundland and southern Gulf of St. Lawrence in 

Canada to New Jersey in the United States. Age and growth estimates for the smooth skate were 

derived from 306 vertebral centra from skates caught in the North Atlantic off the coast of New 

Hampshire and Massachusetts. Male and female growth diverged at both ends of the data range 

and the sexes required different growth functions to describe them. Males and females were 

aged to 15 and 14 years, respectively. 

Age and size at sexual maturity was determined for 185 male and 96 female smooth skates 

(ranging in size from 370 to 680 millimeters total length LT), collected from the western Gulf of 

Maine (Sulikowski et al. 2009). Fifty percent maturity occurs between 9 and 10 years and 560 

millimeters LT for males, and occurs at age 9 years and 540 millimeters LT for females. 

Northeast Skate Complex 

Skates caught off Rhode Island for use in the lobster bait industry were sampled from January 

through September 2009 in response to the FMP objectives to collect information critical for 

improving knowledge of the identification of these species, monitoring their status and 

improving management approaches. Data including date, catch location, species name, total 

length, disk width, and weight were collected from 2,213 skates from boats out of Point Judith 

and Little Compton, Rhode Island. Of the skates sampled, 2024 were identified as little skate 

(Leucoraja erinacea), and 189 were identified as winter skate (Leucoraja ocellata). Length 

frequency graphs were produced for both species and weight to length conversion equations 

were calculated. Reproductive measurements and vertebrae were also collected from 39 

individuals for future analysis. 

Angel Shark (Squatina spp.) 

The Atlantic angel shark (Squatina dumeril) is among 20 species of sharks that are prohibited 

from both commercial and recreational fisheries. However off the northeast coast of the U.S., 

this species is encountered in several commercial fisheries including the bottom otter trawl and 

gillnet fisheries. Staff from the NEFSC Observer Program and survey vessels has combined to 

collect 54 angel sharks to date. Dissections of these specimens have resulted in preliminary 

maturity estimates of greater than 1 meter fork length for both male and female angel sharks. 

Preliminary age determination estimates from the vertebrae are similar to results from angel 

sharks from the Gulf of Mexico and Pacific; there does not appear to be any correlation between 

band periodicity and time. Further work is required to determine band periodicity in this species. 

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DNA samples from the western North Atlantic population have also been collected to examine 

the angel shark evolutionary history and population structure using mitochondrial DNA control 

region sequences from the northwest Atlantic, and western and eastern populations from the Gulf 

of Mexico. Results from this collaborative study supports current US fisheries management 

banning all landings of the Atlantic angel shark, with management and conservation units 

established for a single genetic stock until further genetic and tagging programs can be 

conducted. 

Observations of growth and demography in captive-born Pacific Angel Sharks (Squatina 

californica), at Aquarium of the Bay in San Francisco, California were summarized for a 

presentation at the 2012 American Elasmobranch Society Meeting (Grassmann et al. 2012). The 

data collected on these specimens offer a unique opportunity to closely observe the early stages 

of age-related growth in Pacific angel sharks using over two and a half years of regularly 

collected data on each shark’s length, weight, average consumption, and the percentage body 

weight consumed. Initial analysis using standard growth curves did not adequately represent 

these data and the manuscript is currently under revision using other techniques. 

Smalltooth Sand Tiger (Odontaspis ferox) 

The smalltooth sand tiger, a large, deep-water shark species, has been reported as occurring in 

the western North Atlantic Ocean based on a single female caught off the North Carolina coast in 

September 1994 during a research vessel bottom trawl survey. Recently, certified NEFSC 

observers described and photographed two more captured specimens of this species during trawl 

trips targeting squid in waters off the eastern coast of the United States. The International Union 

for Conservation of Nature currently lists the smalltooth sand tiger as vulnerable for the 

following reasons: this species may be naturally rare, has an assumed low fecundity as seen in 

the closely related sand tiger shark, and developing deep-sea fisheries apply an increasing 

amount of pressure. However, as noted in previous accounts, it is only when an occasional 

individual of this deep water species comes onto the continental shelf that there is an opportunity 

for its capture, therefore the smalltooth sand tiger may be more common than suggested by the 

few documented captures. A presentation summarizing some results was given at the 2010 

American Elasmobranch Society Meeting. 

Dusky Shark (Carcharhinus obscurus) Genetics 

A collaborative study on the genetic stock structure of the dusky shark was conducted to 

delineate management units and monitor trade in sharks (Benavides et al. 2011). This is the first 

assessment of global stock structure of C. obscurus by analyzing part of the mitochondrial 

control region (mtCR) in 255 individuals sampled from 8 geographically dispersed locations 

These analyses suggest that replenishment of the collapsed US Atlantic management unit via 

immigration of females from elsewhere is unlikely. In addition, these mtCR sequences can be 

used to reconstruct the relative contributions of US Atlantic, South Africa, and Australia 

management units to the Asian fin trade. 

Age and Growth of Elasmobranchs 

Accurate age estimation is critical to population assessment and conservation strategies for 

sharks and rays as it allows for the calculation of important demographic information including 

longevity, growth rate, and age at sexual maturity; management decisions based on under ageing 

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can inadvertently lead to overexploitation. The primary method for estimating age of sharks 

relies on counting band pairs that are assumed to be annual in vertebrae. While it is widely 

acknowledged that the assumption of annual deposition should be tested by an independent 

method, most shark species lack this validation. Determining metabolic stability is also critical if 

vertebrae are to be used as lifetime chemical records. White sharks (Carcharodon carcharias), 

basking sharks (Cetorhinus maximus), and dusky sharks (Carcharhinus obscurus) are listed as 

vulnerable on the IUCN Red List of Threatened Species due to a history of overfishing, and all 

three currently lack age validation. A review chapter assessing the age and growth of 

Chondrichthyan fishes was published in 2012 (Goldman et al. 2012). This reported overviews 

on ageing structures, sampling and processing specimens, and methodologies of age 

determination and verification/validation. Implications of growth, longevity, and demography, 

as well as the use of various growth models were also discussed. 

Tiger Shark (Galeocerdo cuvier) 

Age and growth estimates for the tiger shark in the western North Atlantic were derived from 

band counts of 238 sectioned vertebral centra. Growth functions fit to length at age data 

demonstrated that growth rates were similar for males and females up to approximately 200 

centimeters fork length after which male growth slowed. Both sexes appear to reach maturity at 

age 10. Males and females were aged to 20 and 22 years, respectively, although longevity 

estimates predict maximum ages of 27 and 29 years, respectively. Bomb radiocarbon analysis of 

ten band pairs extracted from four vertebral sections suggested that band pairs are deposited 

annually up to age 20. This study provides a rigorous description of tiger shark age and growth 

in the western North Atlantic and further demonstrates the utility of bomb radiocarbon as an age 

validation tool for elasmobranch fishes. 

Sand Tiger (Carcharias taurus) 

There is a great deal of ambiguity in the age and growth data of sand tiger. Of particular concern 

is the observed maximum age based on vertebral band counts. To address this uncertainty, 

archival vertebrae of sand tiger sharks from both the north Atlantic and south Indian Oceans 

were processed for bomb radiocarbon analysis in an effort to validate growth band periodicity 

and longevity in the species (Passerotti et al. 2014). Results from the WNA validated vertebral 

age estimates up to 12 years, but indicated ages of large adult sharks were underestimated by 11­

12 years. Validated lifespan for C. taurus individuals in this study reached at least 40 years for 

females and 34 years for males. 

Basking Shark (Cetorhinus maximus) 

Age and growth of the basking shark was examined using vertebral samples from 13 females 

(261 to 856 centimeters TL), 16 males (311 to 840 centimeters TL) and 11 specimens of 

unknown sex (376 to 853 centimeters TL). Vertebral samples were obtained worldwide from 

museums and institutional and private collections. Examination of multiple vertebrae from along 

the vertebral column of 10 specimens indicated that vertebral morphology and band pair 

(alternating opaque and translucent bands) counts changed dramatically along an individual 

column. Smaller sharks had similar band pair counts along the length of the vertebral column 

while large sharks had a difference of up to 24 band pairs between the highest and lowest count 

along the column. Evidence indicates that band pair deposition may be related to growth and not 

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time in this species and thus the basking shark cannot be directly aged using vertebral band pair 

counts. 

Dusky Shark (Carcharhinus obscurus) 

A revision of the age and growth of the dusky shark in the Northwestern Atlantic Ocean was 

completed (Natanson et al. 2013) where sample collection spanned the years prior to and 

following the implementation of management measures (1963 to 2010). Growth was compared 

pre- and post-population depletion and pre- and post-management to investigate the possibility of 

density-mediated shifts in age and growth parameters over time. There was no evidence of 

difference between periods for either sex. Additionally, bomb radiocarbon dating was used to 

determine the periodicity of band pair formation. Results support the traditional interpretation of 

annual band pairs up to approximately 11 years of age. After this time, vertebral counts 

considerably underestimate true age. Maximum validated ages were estimated to be between 38 

and 42 years of age (an increase of 15 to 19 years over the band count estimates), confirming 

longevity to at least 42 years of age. Growth curves estimated using only validated data were 

compared to those generated using band pair counts. Logistic growth parameters derived from 

validated vertebral length-at-age data were L∞= 261.5 centimeters FL, Lo=85.5 centimeters, 

to=4.89 year and g= 0.15 year−1 for the sexes combined. Revised estimates of age at maturity 

were 17.4 years for males and 17.6 years for females. 

Bull Shark (Carcharhinus leucas) 

The bull shark is a common coastal carcharhinid that is widely distributed in tropical and 

subtropical areas of the world's oceans. Bull sharks can also travel into warm rivers and lagoons. 

In the western North Atlantic, the bull shark is distributed from Massachusetts to southern Brazil, 

including the Gulf of Mexico and Caribbean Sea and the Bahamas. It also occurs in the 

Mississippi and Atchafalaya Rivers in the Southwestern U.S. In conjunction with Doug Adams 

of the Florida Fish and Wildlife Conservation Commission, age and growth of the bull shark was 

completed (Natanson et al. 2014) using 121 vertebral samples collected between 1966 and 2010 

in the western North Atlantic Ocean. The maximum age based on vertebral band pair counts was 

25 (184 centimeters FL) and 27 (196 centimeters FL) years for males and females, respectively. 

The logistic (male: asymptotic FL = 204.8 centimeters, growth coefficient = 0.163 yr-1) and 

Gompertz (female: asymptotic FL = 215.1 centimeters, growth coefficient = 0.154 yr-1) growth 

models fitted the size-at-age data best for males and females, respectively. Based on previously 

published estimates of length at maturity, males mature at 15-17 years (176 - 185 centimeters 

FL) and females at 15 years (189 centimeters FL). 

Sandbar Shark (Carcharhinus plumbeus) 

A bomb radiocarbon and tag-recapture dating study was completed to determine valid ageestimation criteria and longevity estimates for the sandbar shark (Andrews et al. 2011). Results 

indicated that current age interpretations based on counts of growth bands in vertebrae are 

accurate to 10 or 12 years. Beyond these years, bomb radiocarbon and tag-recapture data 

indicated that large adult sharks were considerably older than the estimates derived from counts 

of growth bands. Three adult sandbar sharks were 20 to 26 years old based on bomb radiocarbon 

results; a 5- to 11-year increase over the previous age estimates for these sharks. The tagrecapture data provided results that were consistent with bomb radiocarbon dating and further 

supported a longevity that exceeds 30 years for this species. 

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Scalloped Hammerhead (Sphryna lewini) 

Scalloped hammerheads are apex predators with circumglobal distribution in tropical and warm 

temperate waters. Their role in the western North Atlantic ecosystem was explored by 

examining indices of standardized diet composition derived from stomach contents of sharks 

caught from research and commercial vessels, and in recreational tournaments. Impacts on the 

diet caused by biotic and abiotic factors were evaluated. Sample location had the strongest 

influence on diet with sharks occurring in inshore waters feeding primarily on inactive demersal 

fish and secondarily on pelagic fish. Cephalopods were by far the largest food group found in 

sharks caught offshore. There were fewer empty stomachs found in the offshore sample (33 

percent) than in the inshore sample (45 percent), but the volume of stomach contents in those 

with food was higher inshore (0.6 percent body weight (BW) versus 0.4 percent BW). Season 

also played a significant role in the diet. The lowest percentage empty (9.6 percent), the largest 

average stomach content volume (0.8 percent BW), and the largest number of prey items per 

stomach (8.1), occurred in the summer. The summer sample also had the largest number of 

different prey types (1.8), although this was not statistically different from the other seasons. 

Most of these seasonal differences were found in sharks caught both inshore and offshore. Shark 

sex, state of maturity, decade caught, and gear type or source had little or no significant influence 

on diet. 

Shortfin Mako (Isurus oxyrinchus) 

The diet and daily ration of the shortfin mako in the inshore waters of the western North Atlantic 

were re-examined to determine whether fluctuations in prey abundance and availability are 

reflected in these two biological variables. During the summers of 2001 and 2002, stomach 

content data were collected from fishing tournaments along the northeast coast of the United 

States. These data were quantified by using four diet indices and were compared to index 

calculations from historical diet data collected from 1972 through 1983. Bluefish (Pomatomus 

saltatrix) were the predominant prey in the 1972–83 and 2001–02 diets, accounting for 92.6 

percent of the current diet by weight and 86.9 percent of the historical diet by volume. From the 

2001– 02 diet data, daily ration was estimated and it indicated that shortfin makos must consume 

roughly 4.6 percent of their body weight per day to fulfill energetic demands. The daily 

energetic requirement was broken down by using calculated energy content for the current diet of 

4909 kilojoules per kilogram. Based on the proportional energy of bluefish in the diet by weight, 

an average shortfin mako could consume roughly 500 kilograms of bluefish per year off the 

northeast coast of the United States. 

Sandbar Shark (Carcharhinus plumbeus) 

Non-lethal diet sampling of juvenile sandbar sharks was conducted during summer months in 

Delaware Bay, one of the largest nurseries for the species in the western North Atlantic. Overall, 

sandbar sharks had a pattern characterized by a diverse diet, intermittent feeding, and occasional 

consumption of large meals. Significant ontogenetic changes in diet to progressively higher 

trophic-level prey were discovered. Sharks fed principally on teleosts, with crustaceans 

important to young sharks, and elasmobranchs an increasing dietary component for large 

juveniles. Small teleost prey, were consumed more frequently by small sharks; whereas large 

teleosts became more common in big sharks. Significant monthly changes in feeding patterns 

were exhibited by young of the year (YOY) where June YOY contained less total prey, ate 

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smaller meals, and consumed predominantly less mobile species. August 

YOY diet was similar in composition to small juvenile diet from June 

and July, and small juvenile diet in August was more consistent with the 

diet of large juvenile sharks. The dramatic monthly changes in feeding by 

YOY suggested improvement in hunting capability by late summer, with 

some shifts to larger or more mobile prey continuing in juveniles. 

Overall, monthly peaks in consumption of some prey were consistent 

with reported times of peak abundance for those species, and this 

suggested a generally opportunistic strategy of feeding on abundant 

species. 

Results from the non-lethal stomach eversion technique for sandbar 

sharks shows great promise for trophic ecology studies. The technique 

involves inserting PVC pipe appropriately sized to the mouth and 

pharynx into the throat and the stomach past the cardiac sphincter. The 

pipe is slowly removed generating negative pressure, which draws the 

stomach into the pipe and down into the mouth. In most cases, the 

stomach returned to its natural position when the shark was held upright; 

otherwise forceps were used. Only four sharks could not be everted and 

had to be sacrificed; all contained extremely large meals (greater than 3.3 percent BM) of either 

teleost or elasmobranch prey in the earliest stages of digestion. This technique was considered 

effective at limiting sampling mortality as 19 (1.8 percent) of 1,051 tagged and everted sharks 

were recaptured to date. Time at liberty (3 – 1,732 days) and straight line distance traveled (0 – 

506 kilometers) varied, though 68 percent of sharks were recaptured in Delaware Bay. The tag 

return rate and movements were similar to other studies on C. plumbeus in the region. 

Additionally, sharks kept in tanks for feeding experiments survived multiple eversions. 

Smooth Dogfish (Mustelus canis) 

Quantitative ontogenetic, sexual, and monthly differences in food habits and feeding patterns of 

smooth dogfish were examined in Delaware Bay with 98 percent of the stomachs containing 

food with an average of eight prey items in various digestive states per stomach, indicating a 

continuous feeding pattern. This shark species fed upon an array of invertebrate prey with 

significant ontogenetic shifts in prey composition. Young of the year consumed smaller and less 

mobile invertebrates; larger sharks had a diet of predominately benthic macro-invertebrates, 

including most common large crab species, several gastropods, and a few teleosts. Differences 

in meal size, diet diversity, prey number, and total biomass among size classes were limited, 

indicating limited ontogenetic changes in foraging patterns. Some changes in diet composition 

between months occurred but likely reflected shifts in prey availability or habitat usage. The 

continuous feeding pattern of this species may help compensate for the lower energetic value of 

many of the prey. The large number and mass of prey items per stomach, as well as the 

abundance of this species, indicate that this species plays an important role in the trophic 

relationships of the macro-invertebrate community in the bay. 

In collaboration with Massachusetts Division of Marine Fisheries, staff is also working to 

examine the feeding ecology of smooth dogfish in Massachusetts waters. This study was 

designed to characterize the diet of smooth dogfish where there is significant overlap with higher 

Figure 5.12. Juvenile 

sandbar shark on NEFSC 

COASTSPAN Survey 

bottom longline. 

Source: NMFS photo. 

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densities of American lobster (Homarus americanus). Consumption of lobster by predators such 

as smooth dogfish is thought to be extensive in this area, and may have led to the drastic decline 

in local abundance of the lobster over the last decade. Preliminary analysis found CPUE was 

greatest in the earlier months of the survey largely because of the abundance of male smooth 

dogfish. The sex ratio was dominated by males in May and June and then shifted toward females 

in the summer months. A dramatic decrease in the number of males occurred in July which 

coincided with peak water temperatures within the bay during the same period. Stomach 

contents of all dogfish were everted and analyzed. The diet of the smooth dogfish consisted 

mostly of crustaceans, with lobster, rock crab, common spider crab, and mantis shrimp among 

the most common prey items. Preliminary analysis suggest that smooth dogfish may be an 

underestimated predator of the American lobster population in Buzzards Bay, but the extent to 

which they impact the lobster population remains to be determined. 

Resource Partitioning Between Shark Species 

Comparative feeding ecology and size-specific resource partitioning was examined between two 

abundant shark species in Delaware Bay, the sandbar shark and smooth dogfish. Foraging 

patterns differed distinctly; the smooth dogfish exhibited continuous feeding with numerous 

small meals, whereas the sandbar shark consumed larger less frequent meals. Diet overlap 

between the species was restricted to adult smooth dogfish and young of the year (YOY) sandbar 

shark, which exhibited differences in temporal and spatial distribution within the Bay. Adult 

smooth dogfish were captured in deeper regions, especially after June, more often than YOY 

sandbar shark, which were principally captured in very shallow regions, particularly early in the 

summer. Thus, these two shark species partition resources by a combination of ontogenetic and 

monthly differences in diet and habitat use. 

Temporal Changes in Diet 

Using the food habits data collected by the NEFSC Apex Predators Program over the past 38 

years, we examined temporal changes in prey species, taxonomic and ecological prey groups, 

and overall trophic levels for the blue shark and the shortfin mako. Indices of standardized diet 

composition were analyzed to identify changes in the prey species consumed, and then related to 

temporal changes in the distribution and abundance of these prey items. The two shark species 

have dissimilar feeding strategies and respond differently to environmental changes and 

fluctuations in prey availability. The blue shark has a generalized diet and easily switches 

between prey types. Over the four-decade period, some prey categories showed dramatic 

increases in the diet (spiny dogfish, marine mammals), others declined (cephalopods, flatfishes, 

hakes), and others fluctuated (bluefish, herrings, mackerels). The shortfin mako is more 

specialized, consuming mainly bluefish, and appears resistant to dietary change when its 

preferred prey becomes less abundant. A presentation summarizing some results was given at 

the 2010 American Elasmobranch Society Meeting. 

Basking Shark Isotope Analysis 

Researchers at the Woods Hole Oceanographic Institution, Massachusetts Division of Marine 

Fisheries, and the NEFSC are using isotopic analysis on vertebrae to determine the trophic 

position of the basking shark as well as to learn more about their migratory behavior and ocean 

connectivity. This type of retrospective trophic-level reconstruction has broad applications in 

100
 
 

 

 

 

 

 

 

future studies on the ecology of this shark species to determine lifelong feeding and migratory 

patterns and to augment electronic tag data. 

Sable Island Seal Predation 

An investigation into shark predation on five species of seals on Sable Island, Nova Scotia, 

Canada, was completed in conjunction with Sable Island researcher Zoe Lucas (Lucas and 

Natanson 2010). Between 1993 and 2001, 4,906 seal corpses bearing wounds likely inflicted by 

sharks were examined on Sable Island, Canada. Five seal species were involved: grey 

(Halichoerus grypus), harp (Pagophilus groenlandica), harbor (Phoca vitulina), hooded 

(Cystophora cristata), and ringed (Phoca hispida) seals. Flesh wounds on seal corpses indicated 

that two or more shark species prey on seals in waters around Sable Island. Wounds were 

categorized as either slash or corkscrew, with different predators identified for each type. 

Wound patterns, tooth fragments, and marks on bones indicated that white sharks (Carcharodon 

carcharias) were involved in the slash wounds, which comprised a small proportion of attacks. 

98 percent of seal corpses, however, bore the corkscrew wounds that could not be attributed to 

shark species identified in attacks on pinnipeds in other regions and these wounds are previously 

unreported in the literature. Circumstantial evidence indicates that attacks by Greenland sharks 

(Somniosus microcephalus) were responsible for the clean-edged encircling corkscrew wounds 

seen on seal corpses washed ashore on Sable Island. This research was the basis of an episode of 

National Geographic Predator CSI entitled, ‘Corkscrew Killer.’ 

Cooperative Shark Tagging Program (CSTP) 

The CSTP provides information on distribution, movements, and essential fish habitat for shark 

species in U.S. Atlantic and Gulf of Mexico waters. This program has involved more than 7,000 

volunteer recreational and commercial fishermen, scientists, and fisheries observers since 1962. 

In 2014, information was received on 5,000 tagged and 600 recaptured fish bringing the total 

numbers tagged to 249,000 sharks of more than 50 species and 15,000 sharks recaptured of 33 

species. To improve the quality of data collected through the CSTP, the Guide to Sharks, Tunas, 

& Billfishes of the US Atlantic and Gulf of Mexico has been reprinted and made available to 

recreational and commercial fishermen through the Rhode Island Sea Grant. In addition, 

identification placards for coastal and pelagic shark species were distributed. A toll-free number 

has been established as well as online reporting to collect information on recaptures for all 

species. 

Alternative tag testing is underway utilizing recreational tag and release tournaments; the most 

recent in February of 2009. These events offer an opportunity to investigate the use of two new 

dart tags on coastal and pelagic sharks. Many of these events have 100 percent observer 

coverage on the recreational boats and observers alternatively using each tag type and recording 

tag data, release condition, and total catch and effort. This will allow an initial evaluation of 

these tags by getting feedback from the participants on how easy each tag is to handle, how well 

they stay on the tagging needle, and how easily the dart head penetrates the shark skin. This 

feedback on tag use and subsequent recaptures will enable us to begin to evaluate these tag types 

for future use. 

Integrated Mark-Recapture Database Management System (I-MARK) 

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The NEFSC Integrated Mark-Recapture Database System (I-MARK) provides a platform to keep 

multi-species tagging program data in a common format for management and analysis. Initiated 

by the Cooperative Research Program, the database design and application were developed 

collaboratively by the shark, yellowtail flounder, black sea bass, and scup tagging programs and 

Data Management Systems. A web application is used for data input and quality control. IMARK was designed to track fish and tags independently. It consists of several web application 

modules including inventory of tags, initial release events, subsequent recapture events, bulk 

data entry of cruise releases, contact name and address information, map display, reports and 

statistical queries. Fate of animal, fate of tag, double tags, and multiple recaptures can be 

accommodated within the database. Extensive quality control is achieved using the web 

application to enter and maintain the I-MARK data. These audits can be applied to data for all 

fisheries or a specific fishery and encompass standard audits such as checking data type, land 

locations, and allowable values as well as more complex validations which check relationships 

between the fate of animal, fate of tag and event type. A constituent release recapture letter is 

generated by the web application with a map, size, location, time at liberty and distance traveled 

information. To date, all scanned tag card images from the CSTP have been linked to the 

existing I-MARK system. 

Porbeagle (Lamna nasus) Movement Patterns 

A study on the movement patterns, habitat utilization, and post-release survivorship of 

porbeagles captured on longline gear in the North Atlantic is in conjunction with scientists from 

MDMF and the University of Massachusetts. The primary objective of this research is to deploy 

PSAT tags to examine the migratory routes, potential nursery areas, swimming behavior, and 

environmental associations that characterize habitat utilization by porbeagles. Information will 

be obtained to validate the assessment of the physiological effects of capture stress and postrelease recovery in longline-captured porbeagles. These efforts will potentially allow the 

quantification of the stress cascade for this shark species captured using commercial gear, 

thereby providing fishery managers with data showing the minimum standards for capturing 

(e.g., longline soak time) and releasing these fishes to ensure post-release survival. Based on 

known and derived geopositions, the porbeagles exhibited broad seasonally-dependent horizontal 

(77-870 kilometers) and vertical (surface to 1,300 meters) movements. All of the sharks 

remained in the western North Atlantic from the Gulf of St. Lawrence and the coast of Nova 

Scotia to Georges Bank and oceanic and shelf waters south to North Carolina. In general, the 

population appears to contract during the summer and fall with more expansive radiation in the 

winter and spring. Although sharks moved through temperatures ranging from 2-26°C, the bulk 

of their time was spent in water ranging from 8-16°C. In the spring and summer months, the 

sharks remained epipelagic in the upper 200 meters of the water column. In the late fall and 

winter months, some of the porbeagles moved to mesopelagic depths (200-1,000 meters). 

Temperature records indicate that these fish were likely associated with the Gulf Stream. 

Additional analyses, which include the integration of these data with those from the long-term 

conventional tag-recapture database, are ongoing. Since none of these fish moved to the NE 

Atlantic, this work also supports the two stock hypotheses for the North Atlantic. 

Atlantic Sharpnose Shark (Rhizoprionodon terranovae) Movement Patterns 

A total of 4,653 Atlantic sharpnose sharks were released with tags along the U.S. east coast and 

the Gulf of Mexico between 1969 and 2012 (Kohler et al. 2013a). Of the 4,370 fish of known 

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sex, 2,612 (60 percent) were males and 1,758 (40 percent) were females resulting in a 1:0.67 

male: female sex ratio. The largest measured male and female fish were 109.2centimeters and 

114centimeters FL, respectively. The mean fork length for both males and females and overall 

was 71 centimeters. A total of 77 sharks were recaptured from 1969 through 2012 with an 

overall recapture rate of 1.7 percent and mean distance traveled of 103 nautical miles. Young of 

the year had the highest displacement (187 nautical miles) relative to the other life-stages 

(juvenile, 140 nautical miles; mature, 83 nautical miles). The Atlantic sharpnose shark at liberty 

the longest was 7.3 years and was recaptured 70 nautical miles from its original tagging location. 

The longest distance traveled was 570 nautical miles from a fish that was originally tagged off 

Texas and recaptured in Mexican waters 4.8 months later. There was no movement between the 

Atlantic and Gulf of Mexico. The majority of the recaptured fish showed Atlantic coastal 

movements with some exchange between US Gulf and Mexican waters. Eight Atlantic 

sharpnose sharks that were tagged off Texas were recaptured off Mexico; this represents 0.2 

percent of the total number of sharks tagged. 

Bonnethead (Sphyrna tiburo) Movement Patterns 

A total of 4,123 bonnetheads were released with tags along the U.S. east coast and the Gulf of 

Mexico between 1965 and 2012 (Kohler et al. 2013b). Of the 3,938 fish of known sex, 934 (24 

percent) were males and 3,004 (76 percent) were females resulting in a 1:3.22 male: female sex 

ratio. The largest measured male and female bonnetheads were 122centimeters FL and 

135centimeters FL, respectively. The mean fork length for both 

males and females was 60.4 and 77.3centimeters FL, 

respectively and overall was 73.2centimeters FL. A total of 172 

sharks were recaptured from 1972 through 2012 with an overall 

recapture rate of 4.2 percent and mean distance traveled of 10.0 

nautical miles. Young of the year had the highest mean 

displacement (32 nautical miles) relative to the juvenile and 

mature sharks (11 nautical miles and 6 nautical miles, 

respectively). The bonnethead at liberty the longest was 7.0 

years (2,572 days) and was recaptured 1 nautical mile from its 

original tagging location off the coast of South Carolina. The longest 

distance traveled was 301 nautical miles from a fish that was 

originally tagged off Bulls Bay, South Carolina and recaptured off 

Melbourne Beach, FL, 7.9 months later. Both fish were released 

again after recapture. There was no movement between the Atlantic 

and Gulf of Mexico. The majority of the recaptured fish showed small Atlantic and Gulf coastal 

movements with only one bonnethead recovered just into Mexican waters. 

Blacktip Shark (Carcharhinus limbatus) Movement Patterns 

Mark/recapture data from the National Marine Fisheries Service (NMFS) Cooperative Shark 

Tagging Program (CSTP) were summarized for the blacktip shark in the Gulf of Mexico from 

1964 through 2011 (Swinsburg et al. 2012, Swinsburg 2013). Survival estimates based on age, 

sex, and geographic grouping were generated using the program MARK. Data on fork length, 

life stage, movement, time at large, and displacement were also provided. No blacktip sharks in 

this study moved between the Gulf of Mexico and the Atlantic or Caribbean. Similarly, there 

was no evidence of exchange between the eastern and western Gulf of Mexico. Blacktip sharks 

Figure 5.13. Tagged 

blacktip shark on NEFSC 

Coastal Shark Bottom 

Longline Survey. 

Source: NMFS photo. 

103
 
 

 

 

 

 

 

 

were distributed strictly within the 200 m depth contour. Some (sample size of 33 individuals) 

of these sharks migrated from the United States to Mexican waters within a time period of less 

than one year. These data were pivotal in determining the need for multiple (Gulf of Mexico and 

U.S. Atlantic) stock assessments for this species. 

Scalloped Hammerhead Shark (Sphyrna lewini) Movement Patterns 

The scalloped hammerhead shark is found circumglobally in temperate to tropical seas and range 

from shallow coastal waters to the continental shelf and beyond. In the northwest Atlantic 

Ocean, this species is found from New York to the Caribbean Sea, and throughout the Gulf of 

Mexico. Despite their worldwide range and encounters with both benthic and pelagic fisheries, 

very little is known of this species' habitat preferences or movement patterns. The objective of 

this study is to analyze mark/recapture data from the CSTP, to investigate movement patterns 

and habitat selection, as well as the possible role that gender and age may play in determining 

these characteristics. A poster summarizing these results (Eddy et al. 2011) was given at the 

2011 American Elasmobranch Society Meeting. 

Smooth Dogfish (Mustelus canis) Movement Patterns 

Off the US Atlantic coast, the smooth dogfish is an abundant coastal species, commonly 

distributed in bays and inshore waters from Massachusetts to Florida on the east coast of the US 

with Cape Cod and Nantucket Shoals as a boundary to their dispersal northward. This species 

has only been caught as an occasional stray in Massachusetts Bay, the Gulf of Maine, and 

Passamaquoddy Bay at the mouth of the Bay of Fundy. Smooth dogfish mark/recapture data 

from the Cooperative Shark Tagging Program were summarized with 1,134 sharks tagged and 37 

of these tagged sharks recaptured, yielding a total of 1,171 smooth dogfish capture locations 

between 1963 and 2013 (Kohler et al. 2014). Smooth dogfish were tagged from the Gulf of 

Maine to the Gulf of Mexico within 200 m depth throughout their range. Females were caught 

more often than males, resulting in a male to female sex ratio of 1:3.2. The largest smooth 

dogfish was estimated as a 130 centimeters FL female. Capture locations for mature females and 

YOY overlap off Long Island NY, in Delaware and Chesapeake Bay, and along coastal North 

Carolina. Maximum displacement distance was 460 nautical miles with distance traveled 

increasing with increasing FL for the 12 fish at liberty less than 1 year. Seasonal changes in 

tagging locations were evident. This north-south seasonal migration pattern is further revealed 

by recaptures at liberty for less than one year with movements between Cape Cod, MA and 

North Carolina. Overall, none of the smooth dogfish moved between the Atlantic and Gulf of 

Mexico. 

Post-release Recovery and Survivorship Studies in Sharks—Physiological Effects of Capture 

Stress 

This ongoing cooperative research is directed toward coastal and pelagic shark species caught on 

recreational and commercial fishing gear. This work is collaborative with researchers from 

Massachusetts Division of Marine Fisheries (MDMF) and many other state and academic 

institutions. These studies use blood and muscle sampling methods, including hematocrit, 

plasma ion levels, and red blood cell counts, coupled with acoustic tracking and pop-up satellite 

archival tags (PSAT) data to quantify the magnitude and impacts of capture stress. The primary 

objectives of the new technology tag studies are to examine shark migratory routes, potential 

nursery areas, swimming behavior, and environmental associations. Secondarily, these studies 

104
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

can assess the physiological effects of capture stress and post-release recovery in commerciallyand recreationally-captured sharks. These electronic tagging studies include: 

1) Acoustic tagging and bottom monitoring studies for coastal shark species in Delaware 

Bay and the USVI as part of COASTSPAN; 

2) Tracking of porbeagle sharks with acoustic and PSATs in conjunction with the MDMF; 

3) Placing real-time satellite (SPOT) and PSAT tags on shortfin makos and blue sharks in 

the Northeast U.S. and on their pelagic nursery grounds; 

4) Placing PSAT tags on sand tigers in Delaware Bay and Plymouth Bay (MA) as part of a 

fishery independent survey and habitat study; and 

5) Placing PSAT and SPOT tags on dusky and tiger sharks in conjunction with Monterey 

Bay Aquarium, University of California Long Beach, and MDMF. 

Integration of data from new-technology tags and conventional tags from the CSTP is necessary 

to provide a comprehensive picture of the movements and migrations of sharks along with 

possible reasons for the use of particular migratory routes, swimming behavior, and 

environmental associations. In addition, the results of this research will be critical to evaluate 

the extensive current catch-and-release management strategies for sharks. 

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Internet Sources and Information 

Federal Management 

2000 Shark Finning Prohibition Act 

http://www.gpo.gov/fdsys/pkg/BILLS-106hr5461enr/pdf/BILLS-106hr5461enr.pdf 

The 2010 Shark Conservation Act 

http://www.gpo.gov/fdsys/pkg/BILLS-111hr81enr/pdf/BILLS-111hr81enr.pdf 

The Office of Sustainable Fisheries 

http://www.nmfs.noaa.gov/sfa/ 

Atlantic Ocean Shark Management 

Copies of the 2006 Consolidated Atlantic HMS Fishery Management Plan (FMP) and its 

Amendments and Atlantic commercial and recreational shark fishing regulations and brochures 

can be found on the Highly Migratory Species (HMS) Management Division website at 

http://www.nmfs.noaa.gov/sfa/hms/. Information on Atlantic shark fisheries is updated annually 

in the Stock Assessment and Fishery Evaluation (SAFE) Report for Atlantic HMS, which are 

also available on the website. The website includes links to current fishery regulations (50 FR 

635), shark landings updates, and the U.S. National Plan of Action for Sharks. 

Domestic stock assessments under the SEDAR process are available online at 

http://www.sefsc.noaa.gov/sedar/. 

Pacific Ocean Shark Management 

The U.S. West Coast Highly Migratory Species FMP and the Pacific Coast Groundfish FMP and 

annual SAFE Reports are currently available on the Pacific Fishery Management Council 

website: http://www.pcouncil.org/. 

Data reported in Appendix 1, Table 1.3.3 (Shark landings (round weight equivalent in metric 

tons) for California, Oregon, and Washington, 2001–2010) was obtained from the Pacific States 

Marine Fisheries Commission’s PacFIN Database, which may be found on their website at: 

http://pacfin.psmfc.org/pacfin_pub/data.php. 

Information about pelagic fisheries of the Western Pacific Region FMP is available on the 

Western Pacific Fishery Management Council’s website: 

http://www.wpcouncil.org/fishery-plans-policies-reports/. 

Data reported in Table 1.3.8 (Shark landings (mt) from the Hawaii-based longline fishery and the 

American Samoa longline fishery, 2003-2013) was partially obtained from the Western Pacific 

Fisheries Information Network (WPacFIN). 

http://www.pifsc.noaa.gov/wpacfin/. 

The Bering Sea/Aleutian Islands Groundfish FMP and the Groundfish of the Gulf of Alaska 

FMP are available on the North Pacific Fishery Management Council’s (NPFMC) website: 

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http://www.npfmc.org/bering-seaaleutian-islands-groundfish/. 

Stock assessments and other scientific information for sharks are summarized annually in the 

NPFMC SAFE Reports that are available online: 

http://www.afsc.noaa.gov/REFM/stocks/assessments.htm. 

International Efforts to Advance the Goals of the Shark Finning Prohibition Act 

NOAA Fisheries Office of International Affairs 

http://www.nmfs.noaa.gov/ia/ 

FAO International Plan of Action for the Conservation and Management of Sharks 

http://www.fao.org/figis/servlet/static?dom=org&xml=ipoa_sharks.xml 

U.S. NPOA for the Conservation and Management of Sharks 

http://www.nmfs.noaa.gov/sfa/Final%20NPOA.February.2001.htm 

NAFO Conservation and Enforcement Measures 

http://www.nafo.int/fisheries/frames/cem.html 

IATTC: http://iattc.org/HomeENG.htm 

ICCAT: http://www.iccat.int/en/ 

International Scientific Committee for Tuna and Tuna-like Species in the North Pacific Ocean 

(ISC): http://isc.ac.affrc.go.jp/ 

WCPFC: https://www.wcpfc.int/ 

UNGA: http://www.un.org/en/law/ 

Memorandum of Understanding on the Conservation of Migratory Sharks 

http://sharksmou.org/ 

U.S. Imports and Exports of Shark Fins 

Summaries of U.S. imports and exports of shark fins are based on information submitted by 

importers and exporters to the U.S. Customs and Border Protection. This information is 

compiled by the U.S. Census Bureau and is reported in the NMFS Trade database: 

http://www.st.nmfs.noaa.gov/commercial-fisheries/foreign-trade/index 

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