Diet of elasmobranchs captured in the fishing of pink shrimp off souther of Brazil / Dieta de elasmobrânquios capturados na pesca de camarão-rosa no sudeste e sul do Brasil

Abstract

Some fish species compose the so-called bycatch caught by pink shrimp trawling, including elasmobranchs (sharks and rays). The objective of the study was to analyze the stomach contents of the captured and compare the items identified in the literature. The material was requested to the commercial vessels that landed in Guarujá, São Paulo, being the study area between Rio de Janeiro and Santa Catarina, from 5 to 75 meters deep. In the laboratory, total length-TL and sexing (shark and ray), fork length-FL (shark), disk width- DW (ray) in centimeters, and total weight- TW in kilograms (shark and ray). For the stomach contents, the Degree of Repletion adjusted (empty and full), the Degree of Digestion (undigested and unidentified), frequency of occurrence (%FO) and the numerical frequency (%FN). Sixty-two specimens were analyzed: 20 rays (seven Atlantoraja castelnaui , five A. cyclophora , five Dasyatis hypostigma , one Myliobatis freminvillei , one Gymnura altavela and one Sympterygia bonapartii ); and 42 sharks (29 Squatina guggenheim and 13 S. occulta ), between June 12 to September 19, 2015 and June 15 to December 29, 2016. Most of the food items had been mentioned in the literature, however others only in this study as : Sycionia sp. and Dactylopterus volitans ( D. hypostigma ); Polydactylus sp., Pogonias cromis and Dactylopterus volitans ( S. guggenheim ); and Porichthys porosissimus ( S. occulta ).