Abstract

Increasing attention is now being paid to an ecosystem-based approach to fisheries management, requiring quantitative assessments of feeding habits of the fish species being managed, so that trophic linkages among species, and interactions among fisheries targeting different species within the same ecosystem may be considered. This study focuses on the diets of large pelagic species targeted by the Barbados longline fishery. Between August 2004 and March 2005, 113 large predators were sampled on commercial longline trips. Diet composition by numerical abundance was, for yellowfin tuna: 47% fishes, 37% squids and 17% crustaceans; for blue marlin: 94% fishes and 6% squids; for white marlin: 83% fishes, 17% squids; for Atlantic sailfish: 47% fishes, 53% squids. A wide range of prey species indicated opportunistic predation and overlap in the diet of these large oceanic predators, although blue marlin appeared to be slightly more selective, and only yellowfin tuna ate crustaceans. These data have important implications for the ecosystem model and suggest a close interrelationship among the commercial longline fisheries, offshore surface-trolling fleets and sport fisheries, since they target co-competitors in the pelagic food web of the Lesser Antilles.

PDF Preview