Trends in Shark Abundance from 1974 to 1991 for the Chesapeake Bight Region of the U.S. Mid-Atlantic Coast

Abstract

Recent stock assessments indicate that the shark stock of the western North Atlantic is exploited at a rate twice the maximum sustainable yield. This finding is supported by data generated by the Virginia Institute of Marine Science longline program for sharks of the. Chesapeake Bay and adjacent coastal waters. Trends in catch per unit of effort since 1974 indicate 60-80% reductions in population size for the common species - sandbar (Carcharhinus plumbeus) , dusky (C. obscurus) , sand tiger (Odontaspis taurus), and tiger (Galeocerdo cuvier) sharks. Declines include numbers of individuals for all species, size classes within species, and in one case a strong decline in relative abundance. Given the limited ability of sharks to increase their population size, these results suggest that stock recovery will probably require decades.