Insight into the trophic niche and prey contribution in the diet of Lutjanus griseus (Linnaeus, 1758) captured by artisanal fishing fleet in the central and southwest Gulf of Mexico

Abstract

Lutjanus griseus is a common species for fisheries of the Gulf of Mexico, and it is an effective vehicle to transport energy from low to top trophic levels in the ecosystem. The management of fish populations is based on the modeling and prediction of abundances. To accomplish this, trophic ecology results allow the understanding of habitat use and population expansions. To increase the knowledge in the trophic ecology of L. griseus, this study described its trophic niche, diet composition, and the prey contribution in the formation of muscle tissue. Results showed that the trophic niche in Veracruz was wider than in Campeche, this related to the consumption of prey in different habitats, coral reefs areas in Veracruz and seagrass beds in Campeche. According to the δ13C y δ15N values, in both regions the crustaceans were the most important group in the contribution of muscle tissue, however, it contrasted with the stomach content results, which suggested that the diet in Campeche was mainly composed of crustaceans, and in Veracruz of fishes. This difference could be related to the snapper’s movements, as they can be found in sea bottoms covered with seagrass, with high abundance of crustaceans, and sea bottoms composed of coral reefs with high diversity of fishes and other preys. Results highlight the generalist and opportunistic feeding strategy of L. griseus, this strategy allowed its population expansion to the north, consuming the available food source in the different habitats it occupied.