INVESTIGADORES
BELLEGGIA Mauro
congresos y reuniones científicas
Título:
The diet of the narrowmouthed catshark Schroederichthys bivius in Argentine sea.
Autor/es:
BELLEGGIA MAURO; ZENONI-LUFRANO M; VILLA A.; COLONELLO JORGE; FIGUEROA DANIEL E.; MASSA ANA; GIBERTO DIEGO; BREMEC CLAUDIA
Lugar:
Joao Pessoa
Reunión:
Congreso; Sharks International Conference; 2018
Institución organizadora:
AES, SBELL, SQUALUS
Resumen:
The narrowmouthed catshark Schroederichthys bivius is an endemicspecies of the southwest Atlantic and southwest Pacific continental shelf. Itis distributed from Brazil to Argentina and Chile. In Argentina occurs from 50 to360 m depth. Food habits of S. biviuswere studied based on analysis of stomach contents. Specimens were collectedfrom three research cruises carried out by (INIDEP) during winter 2016 andsummer 2017 on the southern Argentinean continental shelf (ACS, 41oS? 48oS), and during spring 2016 on the northern ACS (35°S ? 41°S).Prey items were identified to the lowest possible taxon, counted and weighted.The percentage of the index of relative importance (%IRI) was used to evaluatethe contribution of each prey. The hypothesis that the consumption of each preygroup is influenced by total length, sex, maturity stage or season was assessedby fitting generalized linear models (GLM). From the 452 catcharks analyzed,all stomachs (100%) contained food. On the southern ACS the species fed mostlyon cephalopods (36.90%) and crustaceans (33.18% IRI), followed by fish (20.36% IRI)and polychaets (24% IRI). On the northern ACS S. bivius fed mainly on crustaceans (56.60% IRI), followed bypolychaets (18.65% IRI), fish (18.09% IRI) and cephalopods (4.71%). Theconsumption of polychaets and crustaceans decrease as the narrowmouthedcatshark grew in size, and they were more consumed during winter than summer.On the other hand, the consumption of cephalopods increased with the totallength of S. bivius and they weremore consumed in summer than in winter. The trophic level was estimated 3.94and 3.57 on the southern and northern ACS, respectively. The traditional IRI and thenew PSIRI indexes are compared and discussed.