Feeding ecology of black scorpion fish (Scorpaena porcus Linnaeus, 1758) in SE Black Sea region, (Ordu) Turkey

Abstract

Black scorpion fish (Scorpaena porcus) is an important species for both artisanal and industrial fisheries in the Turkish Black Sea, with 306 tonnes landed in 2017. The diet composition of this species was investigated through the examination of their stomach contents. A total of 621 S. porcus (ranging from 12.79-765.5 g) were caught by trammel net in the south-eastern Black Sea (Turkish waters) from December 2015 to November 2016. The importance of prey items in the diet of S. porcus was assessed using the Index of Relative Importance (%IRI). Overall, the dominant species was the isopod Idotea balthica (52.8%IRI) followed by decapods (38.5%IRI) and teleosts (8.7%IRI). Seasonal variations in the diets were observed, with isopods predominant in autumn (>85%IRI), teleosts in winter (>77%IRI) and decapod crustaceans (>78%IRI) in spring and summer. The modified Costello's graphical analysis evinced a specialist feeding strategy for S. porcus during winter, spring and autumn while a shift to generalistic feeding strategy was exhibited in summer by a limited number of S. porcus individuals.