CRS Report for Congress
Management of U.S. Fisheries for Highly
Migratory Species
April 21, 2000
Eugene H. Buck
Senior Analyst in Natural Resources Policy
Resources, Science, and Industry Division

Congressional Research Service ˜ The Library of Congress

This document provides general background and identifies current issues of concern
in the domestic and international management of highly migratory fish species (e.g.,
billfish, shark, and tuna). Also discussed are differences among species management
in various U.S. coastal regions. Current legislation and related issues are summarized
for proposals to modify management of sharks, to restrict finning and to ban or
restrict pelagic longline fisheries. This document will be updated periodically as these
issues evolve. Legislation on these issues is tracked in CRS Report IB10010, Fishery,th
Aquaculture, and Marine Mammal Legislation in the 106 Congress.

Management of U.S. Fisheries for Highly Migratory Species
Domestic and international management of highly migratory fish species (e.g.,
marlin, sailfish, swordfish, shark, and tuna) is complex and controversial because these
species migrate across many jurisdictions and are caught in various fisheries where
commercial and sport fishermen compete for harvests. Increasing environmental
concern and user competition for a shrinking resource have led groups to ask
Congress to consider several initiatives that would modify how the United States
manages these fisheries.
Domestically, the National Marine Fisheries Service and regional fishery
management councils have developed management measures for highly migratory
species (HMS) fisheries under the authority of the Magnuson-Stevens Fishery
Conservation and Management Act. Internationally, the United States participates
as a Party to several agreements for managing these species cooperatively. In
addition, a Multilateral High-Level Conference on Conservation and Management of
Highly Migratory Fish Stocks in the Central and Western Pacific is in the final stages
of negotiation.
Swordfish management concerns include overfishing in the Atlantic, with
proposals seeking to prohibit pelagic longline fishing in certain areas of the Atlantic
and Gulf of Mexico and to finance a buyout of longline vessel permits. Legislation
has been introduced in the 106th Congress to implement these proposals (H.R. 3331,
H.R. 3390, S. 1911) or to prohibit all pelagic longline fishing in U.S. Atlantic waters
(H.R. 3516). Shark finning (i.e., removal of fins and discarding of the rest of the
shark carcass) is controversial and currently is prohibited in the Atlantic but allowed
in the Pacific. Legislation (H.R. 3535) in the 106th Congress proposes to prohibit this
practice in the Pacific.
General management issues relate to establishing better means of monitoring the
far-ranging fisheries for HMS, using a combination of satellite technology (e.g., vessel
monitoring systems) and onboard observers, and to minimizing incidental bycatch of
non-target species, such as sea turtles and marine mammals, by HMS fishing gear.
This document will be updated periodically as these issues evolve.

Background ................................................ 1
HMS Management Issues.....................................3
Monitoring ............................................. 3
Bycatch and Protected Species Interactions....................4
Individual Fishery Concerns....................................5
Billfish ................................................ 5
Sharks ................................................ 6
Tuna ................................................. 7
Additional General Considerations...............................7
Congressional Focus.........................................8
List of Tables
Table 1: 1998 U.S. Commercial Landings of
Highly Migratory Fish Species (metric tons).......................1

Management of U.S. Fisheries for Highly
Migratory Species
Under the Magnuson-Stevens Fishery Conservation and Management Act
(MSFCMA; 16 U.S.C. 1802(20)), highly migratory species (HMS) are defined as
tunas, oceanic sharks, and billfishes — marlins (Tetrapturus spp. and Makaira spp.),
sailfishes (Istiophorus spp.), and swordfish (Xiphias gladius). HMS are managed
differently from most fish because their extensive migrations necessitate coordinated
management across many jurisdictions. These fish are caught by U.S. sport and
commercial fishermen in inshore state-managed waters, within the U.S. Exclusive
Economic Zone (EEZ), in the EEZs of central and western Pacific island nations
under treaty agreement, and in international waters. Most of the U.S. commercial
catch of swordfish and sharks is taken within the U.S. EEZ. However, in the Pacific,
the majority of tuna, sharks, and swordfish caught by U.S. commercial fishermen is
taken in international or foreign waters.
Table 1: 1998 U.S. Commercial Landings of
Highly Migratory Fish Species (metric tons)1
Species/Distance from shore0-3 miles3-200 milesHigh seas or foreign
Swordfish 25 5,108 1,713
Tuna 221 21,486 195,769
Sharks (other than dogfish)6185,2561,135
Because of concerns about coordination and logistics, HMS in the Atlantic
Ocean, Gulf of Mexico, and Caribbean Sea are managed by the National Marine
Fisheries Service (NMFS), within the National Oceanic and Atmospheric
Administration, U.S. Department of Commerce, rather than by individual regional
fishery management councils.2 On May 28, 1999, NMFS published a final rule to
begin implementing a new coordinated HMS fishery management plan (FMP) for

1National Marine Fisheries Service. Fisheries of the United States, 1998. Washington, DC:
National Oceanic and Atmospheric Administration, Department of Commerce, Current
Fishery Statistics No. 9800, July 1999. p. 14-19.
2Under the MSFCMA, eight regional fishery management councils generally develop plans
and recommendations for regional fisheries, which NMFS then implements.

tuna, sharks, and swordfish in the Atlantic Ocean and Gulf of Mexico.3 Regulations
implementing amendments to a separate FMP governing billfish management in the
Atlantic and Gulf were published at the same time. More recently, NMFS completed
a Stock Assessment and Fishery Evaluation for Atlantic Highly Migratory Species
(SAFE 2000)4 providing updated background information for managing all Atlantic
HMS fisheries.
In the central and western Pacific (e.g., Hawaii and U.S. Pacific islands), the
Western Pacific Fishery Management Council has a “pelagic” (i.e., open ocean) FMP
for managing HMS, while the Pacific Fisheries Management Council is in the process
of developing an FMP for HMS fisheries along the U.S. west coast. The Pacific
Council’s FMP will likely bring together Washington, Oregon, and California state
regulations relevant to HMS, and may consider limiting entry to control capacity and
effort in west coast HMS fisheries to enhance the economic position of the existing
fleet.5 The Pacific Council’s plan has raised concerns about possible capacity shifts6
among HMS fishermen.
The International Commission for the Conservation of Atlantic Tunas (ICCAT)
coordinates international management of tuna and swordfish in the Atlantic.7 In theo
eastern tropical Pacific (east of 150W longitude), the long-established Inter-American
Tropical Tuna Commission (IATTC) sets quotas for two tuna species (yellowfin and
bigeye), has work groups dealing with important management issues (e.g., fleet
capacity, bycatch, management of fisheries on fish aggregating devices), and is
addressing major administrative concerns (e.g., financing, compliance, renegotiation
of its convention). Renegotiating its convention will bring the IATTC into line with
the provisions of the United Nations Convention on Law of the Sea and its
Implementing Agreement (Agreement on Conservation and Management of8
Straddling Fish Stocks and Highly Migratory Fish Stocks). If the renegotiated
IATTC convention involves major changes and is signed by the United States, the
Senate may consider its consent to ratification.
In the central and western Pacific (west of 150oW longitude), the Multilateral
High-Level Conference (MHLC) on Conservation and Management of Highly
Migratory Fish Stocks in the Central and Western Pacific9 is in the last stages of its

364 Federal Register, p. 29089-29160, May 28, 1999.
4NMFS documents are available at [].
5The west coast states already limit entry to most fisheries, including the driftnet fishery for
swordfish and sharks off California and Oregon.
6Continued restrictions on groundfish could prompt fishermen to shift to the albacore fishery.
Such a move might exacerbate existing economic concerns arising from too much product
being available without added markets for this seasonal fishery.
7See: [].
8The Department of State’s Bureau of Oceans and International Environmental and Scientific
Affairs is coordinating U.S. involvement in these renegotiations.
9Material related to negotiation of the MHLC are available at

negotiations, focusing primarily on tunas.10 The MHLC likely will implement a vessel
monitoring system (VMS) and national quotas as well as limiting both effort and
capital investment by nation. Since the late 1980s, U.S. purse seine vessels have been
authorized to fish in the exclusive economic zones of many Pacific Island nations
under a treaty between those nations and the United States.11 Many of the principles
and measures (e.g., VMS, observers, and regional vessel registry) of the South Pacific
Tuna Treaty are being adopted into the MHLC, reflecting the favorable experience
with the United States under this Treaty. If the MHLC convention is signed by the
United States, the Senate may consider its consent to ratification.
The United States has ratified the Agreement on Conservation and Management12
of Straddling Fish Stocks and Highly Migratory Fish Stocks. When this Agreement
comes into force, the United States and its flag fishing vessels will be bound by the
decisions of ICCAT and IATTC as well as any MHLC Convention or similar
agreement which enters into force, even if the United States does not sign the MHLC
Convention or even join the international organization.
HMS Management Issues
Monitoring. Monitoring of fleet activities is necessary for good data collection
and effective enforcement over the extensive range of HMS fisheries. Due to the
multi-jurisdictional and far-ranging nature of HMS fisheries, there is increasing
interest in using satellite technology and naval/coast guard resources to regulate HMS
fisheries and apprehend “flag of convenience” vessels catching HMS fish illegally. To
better manage the pelagic longline fishery in the Atlantic and identify where individual
vessels are fishing, NMFS is implementing a vessel monitoring system (VMS) for U.S.
pelagic longliners in the Atlantic beginning September 1, 2000.13 In the Pacific,
NMFS conducted a Hawaii longline pilot VMS study between January 1, 1996, and
March 15, 1997. VMS is seen by many as the most effective way to enforce the
closing of fishing areas and monitor where vessels fish. However, issues such as
proprietary interests (since fisherman make their living by knowing where to fish) and
who should pay (since VMS is fairly expensive) make VMS implementation
controversial. Indeed, a lawsuit challenging the VMS requirement in the Atlantic is

9 (...continued)
10The Western Pacific Fishery Management Council has coordinated U.S. involvement in the
negotiation process along with the Department of State’s Bureau of Oceans and International
Environmental and Scientific Affairs.
11Treaty on Fisheries Between the Governments of Certain Pacific Island States and the
Government of the United States of America, Port Moresby, 1987.
12See: []. The Senate approved a
resolution of ratification for this agreement (Treaty Doc. 104-24) on June 26, 1996.
1364 Federal Register, p. 29089-29160, May 28, 1999, with several subsequent delays in
VMS implementation announced by NMFS.

pending in the courts.14 The minimal guidance and apparent lack of authority in the
Magnuson-Stevens Act has impeded the development of monitoring programs such
as onboard observers and VMS, especially regarding the use of industry assessments
to cover program costs so that an entire fleet bears the cost instead of only the vessels
in the fleet that participate in the monitoring program.
Bycatch and Protected Species Interactions. Minimizing interactions with
protected species (e.g., marine turtles) is a concern in the management of fishing gear
for several HMS fisheries. On November 23, 1999, a U.S. District Court judge
ordered NMFS to close a large area off Midway Island to Hawaiian longline
fishermen, to protect sea turtles. Since most of the affected waters are outside the
U.S. EEZ, fishermen from other countries and even other U.S. states (particularly
California) are allowed to fish in the area. Only Hawaiian fishermen are directly
affected by regulations implementing this order.15 The Atlantic longline fishery for
swordfish has a similar problem with sea turtle interactions.
In the eastern tropical Pacific Ocean (ETP), changes to U.S. tuna/dolphin
regulations16 in response to the International Dolphin Conservation Program Act
(IDCPA; P.L. 105-42) have modified the definition of “dolphin-safe,” allowing
yellowfin tuna caught using purse seine nets to be imported into the United States if1718
no dolphins were observed to have been killed or severely injured. The IDCPA
mandates that parties cooperate in the conservation and management of the fish
stocks and deal with such issues as bycatch in the purse seine fisheries. Despite the
continued relatively low mortality of dolphins in the ETP,19 the new NMFS
regulations are highly controversial and were challenged in federal courts by a
coalition of animal protection groups as being insufficiently protective of dolphins.
On Apr. 11, 2000, U.S. District Court Judge Thelton Henderson blocked NMFS
implementation of more relaxed standards for what tuna might qualify to be labeled
as “dolphin-safe,” saying that NMFS had failed to assess whether the proposed
labeling change would cause harm to dolphin populations. Judge Henderson
concluded that NMFS failed to complete critical stress research testing of dolphins
that were repeatedly captured and released.

14Blue Water Fishermen’s Association, et al. v. Daley, Civil Action No. 99CV2846 (RWR)
(United States District Court for the District of Columbia).
1564 Federal Register, p. 72290-72291, December 27, 1999.
1665 Federal Register, p. 30-59, January 3, 2000.
17IATTC guidelines require all vessels harvesting tuna in the eastern tropical Pacific to carry
IATTC-certified observers.
18For additional information, see archived CRS Report IB96011, Dolphin Protection and
Tuna Seining.
19Combined U.S. and foreign dolphin mortality in 1999 was less than 1,500 animals, a
fraction of the estimated several hundred thousand dolphins killed annually in the early 1970s.

Individual Fishery Concerns
Billfish. Other than the commercial harvest of swordfish, billfish are taken
incidentally as bycatch in other commercial fisheries and are targeted and caught by
sport fishermen, many of whom practice catch-and-release and tagging to allow fish
to survive. The commercial catch of swordfish is landed primarily in California
(21.4% of 1998 landings), Florida (11.5%), Massachusetts (9.1%), Louisiana (4.9%),
and Hawaii (much of the remaining 53%).
In late August 1999, the Billfish Foundation, the Coastal Conservation
Association, the American Sportfishing Association, and the Blue Water Fishermen’s
Association signed a Memorandum of Understanding (MOU) wherein both sport and
commercial interests agreed to closing certain areas of the Atlantic Ocean and Gulf
of Mexico to commercial pelagic longline fishing for swordfish and to participating
in financing a buyout of permits for pelagic longline vessels that are responsible for
much of the incidental mortality to undersized swordfish and billfish (i.e., bycatch).
Legislation (H.R. 3331, H.R. 3390/S. 1911) introduced in the 106th Congress would20
implement this MOU.
On December 15, 1999, NMFS published a proposed rule, differing from the
MOU and the introduced bills, that would close different areas in the Gulf of Mexico21
to reduce billfish bycatch but would provide no permit buyout. Some question the
equity of both proposals because the closures in the South Atlantic leave few areas
open to domestic swordfishermen in Florida. In addition, seafood processors in
affected areas claim that, without commercial longlining in the winter months, they
might face bankruptcy. Others are concerned that, without a buyout, the NMFS
proposal might displace commercial vessels to other areas and fisheries. Some
suggest possible benefits from the proposed longline closures for related species,
recalling the improvements in the yellowfin tuna fishery after Japanese longline
fishermen departed from the Gulf of Mexico.
In March 1999, NMFS banned the import of undersized Atlantic swordfish.22
Those regulations assure accurate monitoring of swordfish imports by requiring the
identification of the catching vessel flag (i.e., country of vessel documentation),
certifying that pieces are not from undersized Atlantic fish, and increasing dealer
reporting requirements. Some question whether harvesting only larger swordfish
might raise problems with meeting the U.S. Food and Drug Administration’s
maximum allowable level of 1.0 ppm of methylmercury for these fish. In an effort to
address overfishing of Atlantic swordfish, SeaWeb and the Natural Resources Defense
Council instituted the “Give Swordfish a Break” campaign to discourage consumers
from eating swordfish.23

20See: [
2164 Federal Register, p. 69982-69987, December 15, 1999.
2264 Federal Register, p. 12903-12907, March 16, 1999.
23See: [].

In the Pacific, billfish are valuable for both commercial and recreational
fisheries. Striped marlin are a prized gamefish off California and cannot be sold in the
state. Blue marlin, wahoo, mahimahi, and the tunas are key gamefish in Hawaii and
in some other parts of the western Pacific; however, all of these species are also
valued as commercial products. Only one stock (blue marlin) is thought to be below
the maximum sustainable yield level, although it probably is not overfished as that
term is defined in the Magnuson-Stevens Act.
A major problem throughout the Pacific, including U.S. territories and Hawaii,
is the general dearth of recreational catch and effort data for billfish. While there are
some catch data from tournaments, there is a general lack of effort data, e.g., how
many boats are fishing on any day. Those data need to be linked to the catch data to
provide effective catch per unit effort to better monitor the stock status for individual
Sharks. U.S. commercial shark fisheries occur primarily off Louisiana (19.2%
of 1998 landings), Florida (19.0%), California (7.9%), North Carolina (7.5%), and
Hawaii (much of the remaining 46%). Most sharks caught by sport anglers are
While NMFS prohibits shark finning24 in the Atlantic and Gulf of Mexico, this
practice is still permitted in the Pacific, where blue shark populations (the primary
species finned) are considered to be robust. Shark finning is quite controversial, and
several conservation and animal welfare groups are seeking to prohibit this practiceth
in the Pacific. In the 106 Congress, HCon.Res. 189, H.R. 3078, and H.R. 3535 were
introduced to address these concerns by studying Pacific shark fisheries and/or
prohibiting shark finning. Early in 2000, the Hawaii legislature was also considering
passage of state law to prohibit shark finning. More recently, NMFS received a
petition for rulemaking to prohibit shark finning and require full utilization of sharks
harvested in fisheries managed by the Western Pacific Fishery Management Council.25
In May 1997, some commercial shark fishermen filed suit against NMFS,
challenging commercial harvest quotas for Atlantic sharks. A federal court injunction
resulted in NMFS foregoing its more restrictive management measures, including26
lower quotas slated to take effect on July 1, 1999. In June 1999, a coalition of sport
fishing groups also filed suit against NMFS, charging that shark management focused
inequitably on limiting recreational fishing. No final ruling has yet been made on
either case.
In March 1999, the United Nations Food and Agriculture Organization (FAO)
adopted a voluntary International Plan of Action for the Conservation and
Management of Sharks, requiring participating nations to adopt by 2001 a national
plan for reducing catch in shark fisheries as well as shark bycatch in other fisheries.

24The practice of catching sharks to harvest only the fins for the lucrative Asian shark fin
market, discarding the remainder of the shark carcass as waste.
2565 Federal Register, p. 19734, April 12, 2000.
26Southern Offshore Fishing Ass’n v. Daley, 995 F. Supp. 1411 (M.D. Fla. 1998).

NMFS is preparing, but has not yet published, a proposal for U.S. implementation of
the FAO shark initiative.
Tuna. Commercially, 67% of the world’s tuna harvest is taken in the Pacific.
Because of this, some of the top U.S. ports for tuna landings are in the Western
Pacific (e.g., American Samoa, Guam).27 However, Pacific tuna harvest statistics are
often omitted from NMFS reports because much of the U.S. harvest is caught outside
the U.S. EEZ and is landed in American ports in Samoa, Guam, and elsewhere, along
with sizeable foreign landings. Mainland states with significant commercial tuna
landings include California (7.5% of total 1998 U.S. tuna landings), Washington
(2.9%), Oregon (2.2%), and Louisiana (0.6%). Recreational harvest estimates are
available for yellowfin tuna, with 1998 catch primarily in the South Atlantic region
(62.2% of estimated number of sport-caught fish in 1998), Mid-Atlantic (20.5%), and
Southern California (15.3%).
The Atlantic bluefin tuna fishery is managed through the International28
Commission for the Conservation of Atlantic Tunas (ICCAT). Rebuilding the
population of this species is encouraged by strict harvest quotas. Current ICCAT
concerns focus on minimizing illegal, unreported, and unregulated (IUU) harvests as
well as ensuring that all parties to ICCAT abide by Commission guidelines and
quotas. Unilateral U.S. efforts to rebuild Atlantic bluefin tuna populations have been
frustrated by lax enforcement of ICCAT guidelines elsewhere.
Additional General Considerations
Additional general concerns relating to how NMFS and regional councils
manage HMS fisheries include (not in any particular order): 1) integrating pelagic
species fisheries management, especially when one fishery’s bycatch is the target
species of another fishery, and accounting for bycatch in quota calculations and
fishing effort estimates; 2) incorporating diversity (e.g., differences among commercial
gear types and between sport and commercial users) within and among various user
groups to achieve a sustainable fishery, maintain social equity, and estimate the effects
of proposed regulatory plans, particularly their economic effects; 3) evaluating the
need for a mandatory reporting system for economic data to adequately evaluate the
effects of proposed regulatory changes; 4) determining the cumulative impacts of
HMS regulations on the fishing industry; 5) improving the objectivity and
transparency of NMFS scientific assessment procedures (e.g., more field data
collection and analysis involving stakeholders and independent scientists; less reliance
on computer modeling) that support management and regulatory actions to enhance
agency credibility and forestall litigation; 6) making the role and responsibility of
NMFS’s Atlantic HMS Advisory Panel comparable to that of a regional council to
improve accountability for HMS management decisions; 7) assuring that U.S.
fishermen who abide by international management guidelines are not denied a
reasonable opportunity to harvest the shared resource; and 8) providing sufficient

27See: [].
28For additional information, see CRS Report 95-367 ENR, Atlantic Bluefin Tuna:
International Management of a Shared Resource.

resources to NMFS and the Department of State to allow the United States to make
a significant and lasting contribution to international organizations (e.g., IATTC,
MHLC, South Pacific Tuna Treaty) that are working to achieve compatible
management regimes throughout the ranges of HMS stocks in the Pacific.
Congressional Focus
Environmental concern for declining HMS populations as well as increased
competition between sport and commercial fishermen for preferential allocation of the
less-abundant stocks have brought HMS issues before Congress. The 106th Congress
may choose to address HMS issues when considering whether to close areas to
pelagic longline fishing (H.R. 3331, H.R. 3390, H.R. 3516, S. 1911), whether to take
action on shark finning in the Pacific (HCon.Res. 189, H.R. 3078, H.R. 3535), and
whether to modify management of HMS fisheries during reauthorization and
amendment of the Magnuson-Stevens Fishery Conservation and Management Act.
HCon.Res. 189, expressing the sense of Congress regarding shark finning in Pacific
waters, was the focus of a hearing by the House Subcommittee on Fisheries
Conservation, Wildlife, and Oceans on October 21, 1999. This measure was reported
(H.Rept. 106-428) and agreed to by the House on November 1, 1999. Pelagic
longlining was the subject of two hearings held by the House Resources
Subcommittee on Fisheries Conservation, Wildlife, and Oceans — a July 15, 1999
oversight hearing on NMFS’s regulations implementing the FMP for HMS of Atlantic
Tunas, Swordfish and Sharks, specifically as it affects yellowfin tuna; and a February

8, 2000 hearing on the three House bills addressing pelagic longline fishery issues.29

29For updated legislative action, see CRS Report IB10010, Fishery, Aquaculture, and Marine
Mammal Legislation in the 106th Congress.