Diet of the grey gurnard, Eutrigla gurnardus in the Adriatic Sea, north-eastern Mediterranean

A total of 449 individuals of grey gurnard Eutrigla gurnardus (Linnaeus, 1758) were collected between December 2007 and July 2008 by bottom trawl surveys in the Adriatic Sea, north-eastern Mediterranean. Stomach contents were investigated in order to analyse diet composition according to fish size and depth. The most important prey were Crustacea, mostly Mysidacea such as Lophogaster typicus and Decapoda such as Goneplax rhomboides and Phliocheras bispinosus, followed by Teleostei, mostly Perciformes as Gobius niger and Callionymus spp. Dietary differences were found in relation to a critical predator size of 120 mm (TL). Decapoda were more frequently found in the diet of juveniles and Teleostei in that of adults living at a greater depth. Feeding strategy analyses revealed trophic specialization towards reference prey, thus narrowing the trophic niche.