engleski

Feeding habits of brown ray (Raja miraletus Linnaeus, 1758) from the eastern central Adriatic Sea

The diet and feeding strategy of brown ray, Raja miraletus, from the eastern central Adriatic Sea, were investigated. Stomach contents of 418 specimens, total length (TL) of 13.5 - 40.0 cm, collected from commercial bottom trawls from January to December 2010. were analysed. The prey items identified in the stomachs belong to six major groups: Cephalopoda, Polychaeta, Decapoda (Natantia and Reptantia), Mysidacea, Amphipoda and Teleostei. Decapods were the most important prey (%IRI = 88.2), whereas other prey groups were only occasionally ingested. The fish size was the most important factor affecting diet. According to the observed ontogenetic shift, small sized individuals (< 20 cm TL) fed primarily on small crustaceans (mysids and amphipods), whereas large size specimens consumed bigger prey, such as decapods, cephalopods and teleosts. Diet composition showed little seasonal variation ; decapods were the most important prey in all season. There was high dietary similarity between sampling locations. The percentage of empty stomachs did not differ significantly among size classes and seasons. In terms of composition by species, the diet of brown ray was characterized by variety of rare or unimportant prey. As a result, brown ray could be a considered as generalistic predator.

Adriatic Sea; feeding habits; Raja miraletus

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