Genetic identification of sharks in the U.S. Atlantic large coastal shark fishery*
نویسندگان
چکیده
The U.S. Atlantic large coastal shark fishery grew rapidly during the 1980s when commercial landings increased from 135 metric tons (t) in 1979 to a high of 7122 t in 1989 (NMFS, 1993). In 1993, a quota of 2750 t was established; in 1997 this quota was halved to 1375 t in order to rebuild depleted shark stocks. This fishery targets several species of sharks that are valued for fins (exported to Asia) and meat (sold domestically). Because of the slow growth rate, high age at maturity, and low fecundity of most shark species (Pratt and Casey, 1990), commercial shark fisheries typically collapse after a brief period unless strict conservation measures are implemented (Holden, 1974, 1977; Hoenig and Gruber, 1990). The 1993 shark fishery management plan divided exploited species into three categories: large coastal sharks, small coastal sharks, and pelagic sharks (NMFS, 1993). The category that grew most rapidly was the large coastal shark fishery, which is dominated by several species of requiem sharks and two species of hammerhead sharks. Sound management of a multispecies fishery requires information on the vulnerability of each component of the fishery. Differences in life history characters, e.g. intrinsic growth rates, locations of nursery areas, or migration within or Genetic identification of sharks in the U.S. Atlantic large coastal shark fishery*
منابع مشابه
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