By Shark Info
The following article
is based on a summary of the AFS Policy Statements titled Management of Sharks and
their Relatives (Elasmobranchii) and is reprinted with the permission of J. A.
Musick*, G. Burgess**, G. Cailliet***, M. Cahmi**** and S. Fordham*****.
Regional institutions in the U.S. must give high priority to the management of sharks
and rays because these animals with their slow population growth rates are very
susceptible to overfishing and hence collapse of their populations, according to a
recommendation from the American Fisheries Society (AFS).
rays comprise approximately 1,000 species, whereby most of them have a slow growth
rate, late sexual maturity and a low number of eggs or offspring. Such characteristics
reflect a low increase in population size, combined with a strong susceptibility to
every type of fishing. Managing their populations is thus indispensable, but
unfortunately, the majority of the fisheries which have developed worldwide do not
give this any consideration. In addition, many of the large-sized shark and ray
species demonstrate very extensive migration behavior, making it just as imperative
that national and international agreements are established to regulate their
A basking shark
(Cetorhinus maximus), the second-largest species
of shark next to the whale shark.
© J. Stafford-Deitsch
Several cases of shark populations which collapsed
because of intense fishing practices are well-documented, e.g. the mackerel shark
(Lamna nasus) in the northern Atlantic, the soupfin shark (Galeorhinus galeus) in
California and Australia, the basking shark (Cetorhinus maximus) and the spiny dogfish
(Squalus acanthias) of the North Sea, and more recently the larger species living off
the Eastern Coast of the U.S. The greatest threat appears to come from the mixed
fishing industry which does not concentrate primarily on sharks or rays, but instead
usually catches all types of fish species. To these fishermen it makes no difference
if the sharks and rays caught have undergone noticeable population reductions because
they are not targeted by these industries. An additional problem arises when sharks
and rays are once found in statistics where they are not listed as single individuals
but rather summarized under the category of "sharks" or "rays" so that strong changes
in the respective populations can go on unnoticed. Several large shark and ray species
have a population dynamic which more resembles that of whales or sea turtles. Both of
the latter groups are widely recognized as endangered species and appropriate
protective measures have been taken. Although some of the large-sized rays are also
threatened by extinction, there is no corresponding international [Editor's note]
regulation. Such a regulation is also nonexistent for threatened shark species such as
the gray nurse sharks, dusky sharks and night sharks whose strong population
decimations due to overfishing only recently made them candidates for the List of
Endangered Species, as proposed by the National Marine Fisheries Service (NMFS, U.S.
Department of Commerce).
Even the recognition that a species is in
danger of extinction does not yet mean it will be protected accordingly from
continuous overfishing. The dusky shark (Carcharchinus obscurus), for example, is a
species with one of the slowest growth rates within the family of vertrebrates and
late sexual maturity (20 years). In the past few years its populations have shown an
80-percent decline in the northwestern Atlantic. Still, even though this species is
found on the respective lists, the animals can still be fished because legal
regulations are not yet in force.
Shortly, the FAO (Food and Agriculture Organization) also
joined the discussion on the
worldwide situation of shark populations and made appropriate suggestions for their
management based on an initiative from CITES (Convention on International Trade in
Endangered Species). A large part of the rapidly expanding shark fishery was
stimulated by the finning industry. In the mid-80s the demand for shark fins, used
mainly in soups, skyrocketed and their market value rose from one dollar per pound to
more than 30 dollars upwards. The finning industry only lands the fins ("finning") and
then throws the rest of the still living shark back into the ocean. Besides being
wasteful, this method is also unethical and extremely cruel, not to mention being in
sharp opposition to FAO recommendations. Some U.S. states and the fishing management
plan of the NMFS for Atlantic sharks have now declared "finning" along the Atlantic
coast and parts of the U.S. Pacific coast as illegal.
species living near U.S. coastal regions of the Atlantic undertake extended migrations
and swim to more southerly regions in the colder seasons. Species living in the open
seas, e.g. the shortfin mako (Isurus oxyrhynchus) and the blue shark (Prionace
glauca), even migrate across the entire Atlantic. It is thus logical that species
which migrate beyond national boundaries need to be managed by means of bilateral and
The following suggestions stem partly from
the AFS Policy Statement found in the Management of Sharks and their Relatives,
supplied by courtesy of J. A. Musick et al.
Management: Due to the limited growth
rates of many shark and ray species, high priority must be given to their management
in order to prevent their populations from collapsing through overfishing. Fishing
experts must pay special attention to shark and ray species who are less productive
and are caught in the mixed fishing industry, and by doing so the managers must
maintain the population's biomass above the level normally considered as sufficient.
Legal Regulations: Management means paying special attention that no young animals
are overfished. Thus the appropriate quota regulations and size limits must be
established and enforced in order to guarantee the survival of the necessary
offspring. Management also should mean using the entire shark's body and "finning" as
such should be generally prohibited on a worldwide basis [Editor's Note]. Living
sharks should be released from hooks and set free, and the procedure embodied in an
Agreements: Multilateral agreements should be signed between fishing
nations in connection with species which migrate long distances. The U.S. should
retain its leading role in applying international recommendations, helping other
nations to initiate local shark management plans through technical and financial
Scientific Research: Support must be given to research projects on fishing
practices which reduce shark and ray bycatch and increase their survival rate
following their release.
J. A. Musick is Manager of Vertebrate Ecology Programs
and Systematics at VIMS (Virginia Institute of Marine Science),
Gloucester Point, USA.
G. Burgess is Vice President of the IUCN/SSC Shark
Specialist Group, Florida
G. Cailliet is Professor at Moss Landing Marine
M. Camhi is Assistant Manager of the IUCN/SSC
Shark Specialist Group,
Living Oceans Program, Islip, New York.
S. Fordham is Project Manager, Fishing Industry, at the
Center for Marine Conservation, Washington DC.
Musick, J. A. (1999). Ecology and conservation of
long-lived marine animals. Page 1-10 in J. A. Musick, ed. Life in the slow lane:
ecology and conservation of long-lived marine animals. Am. Fish. Soc. Symp. 23.
Musick, J. A. (1999). Criteria to define extinction risk in marine fishes. The
American Fisheries Society initiatives. Fisheries 24(12): 6-14.
Additional references on this subject can be obtained from the Shark Info Office.
May be published only by indicating the source: Shark Info / Shark Info