Feeding habits and selectivity of the wide-eyed flounder, Bothus podas (Delaroche, 1809) (Bothidae) from the southern Tyrrhenian sea

Abstract

In order to assess the diet composition of the wide-eyed flounder Bothus podas, we analysed the stomach contents of 388 specimens collected seasonally on sandy bottoms of the north-western coast of Sicily (central Mediterranean). The benthic communities in the same area were also studied in order to investigate the feeding selectivity of B. podas. The prey items found in the stomach contents analysed were mostly benthic organisms. The diet composition of B. podas was dominated by Gammaridea, Apseudidae and Cumacea that were also the most abundant categories in the benthic community. Active prey, such as benthic and epibenthic crustaceans, were highly selected, whereas molluscs and polychaetes were only occasionally ingested. Significant differences found in prey abundance by site were related to the different benthic compositions in the sites examined rather than to changes in the feeding behaviour of B. podas. Significant differences in diet by seasons were explained by the highest abundance of Caprellidea, Gammaridea and Cumacea in spring and summer. The observed feeding patterns were related to spatial and temporal variation of prey abundance in the benthos. As a result, B. podas can be considered an active opportunistic predator.