Feeding guilds among batoids in the northwest coast of the Baja California Sur, Mexico

Abstract

AbstractResearch on the feeding habits of batoids provides information of intra and interspecific interactions of this taxon in marine ecosystems. We analyzed 832 stomachs of nine ray species collected from the artisanal fishery on the Northwest coast of Baja California Sur (NBCS). We identified 79 prey items assembled in five trophic groups (crustaceans, fish, mollusks, polychaetes, and sipunculidae). Results indicated that the red crabPleuroncodes planipeswas the most important prey in the diet of the seven batoid species. A low dietary similarity of the rays was observed, which evidenced different feeding strategies. In this regard, we identified four well‐separated trophic guilds. Each guild was characterized by the consumption of specific prey: (1)Hypanus dipterurusandNarcine entemedorthat fed mostly on polychaetes; (2)Rostroraja veleziandGymnura marmoratafed mostly on fishes (Clupeidae and Batrachoididae); (3)Hypanus longus,Myliobatis californica, andPlatyrhinoidis triseriatafed on crustaceans (Munnidae) and Sipunculus worms; and (4)Pseudobatos productusandZapteryx exasperatafed on crustaceans (Portunidae) and fishes (Synodontidae and Batrachoididae). We concluded that batoids off the NBCS show prey sharing between the different species.