Diet composition of the sicklefin smooth-hound shark Mustelus lunulatus caught off El Pardito Island, Baja California Sur, Mexico

Elasmobranchs are frequently apex predators in marine ecosystems, and information on their diet is essential for understanding trophic relationships in these systems. The diet of the sicklefin smooth-hound, Mustelus lunulatus, was investigated through analysis of gut contents. The diet was relatively homogeneous and was dominated by crustaceans, consisting mostly of the anomuran crab Munida tenella (percentage of the prey-specific index of relative importance (%PSIRI) = 30.5) and the bigtooth rock crab Cancer amphioetus (%PSIRI = 9.9). Use of cumulative prey curves as a measure of precision indicated that data were sufficient to fully describe the diet of M. lunulatus. Further studies are necessary to fully characterize diet across sexes and successive age-classes.