The diet of the Narrowmouthed Catshark Schroederichthys bivius, from the Patagonian continental shelf.

BELLEGGIA MAURO; VILLA A.; COLONELLO JORGE; FIGUEROA DANIEL E.; MASSA ANA; GIBERTO DIEGO; BREMEC CLAUDIA

Austin, TX

Congreso; Joint Meeting of Ichthyologists and Herpetologists (JMIH); 2017

American Elasmobranch Society (AES), American Society of Ichthyologist and Herpertologists (ASIH)

The narrowmouthed catshark Schroederichthys bivius is an endemic species of the southwest Atlantic and southwest Pacific continental shelf. It is distributed from Brazil to Argentina and Chile. In Argentina occurs from 50 to 360 m depth. Food habits of S. bivius were studied based on analysis of stomach contents. Specimens were collected from two research cruises carried out by (INIDEP) during winter 2016 and summer 2017 on the southern Patagonian continental shelf (41oS ? 48oS). Prey items were identified to the lowest possible taxon, counted and weighted. The percentaje of the index of relative importance (%IRI) was used to evaluate the contribution of each prey. The hypothesis that the consumption of each prey group is influenced by total length, sex, maturity stage or season was assessed by fitting generalized linear models (GLM). From the 309 catcharks analyzed, all stomachs (100%) contained food. The %IRI revealed that the species fed mostly on cephalopods (36.90%) and crustaceans (33.18%), followed by fish (20.36%) and polychaets (24%). The consumption of polychaets and crustaceans decrease as the narrowmouthed catshark grew in size, and they were more consumed during winter than summer. On the other hand, the consumption of cephalopods increased with the total length of S. bivius and they were more consumed in summer than in winter. The trophic level was estimated 3.94.