Annual variation in diet of Japanesethreadfin bream, ( Nemipterus japonicus ) from Deylam coasts of the Persian Gulf

This study was investigated to determine the annual diet of threadfin bream from Deylam coast of Boushehr Province. Sampling was done seasonally from autumn 1389 to end of summer in 1390. Total length and weight of samples were 18.5 to 28.5 cm and 88.81 to 231.18 g, respectively. Gastrointestinal emptiness index, mean relative length of the intestine and mean feeding rate were 19.4, 1.07±0.18 and 99.50±16.97 respectively. Results showed that food preference of threadfin bream is related to season which feeding more on fish in autumn and winter but in spring, more feeding on gastropods. In autumn and winter, fish and in spring, gastropods were main food items of threadfin bream. Also, with increase in length of fish, their diet leads to ingest more crustaceans as in length of 25-29 cm, 22-25 cm and 18-22 cm crustaceans, fishes, and gastropods and fishes were the most ingested prey, respectively. This study show that threadfin bream is carnivorous species and fishes are the main diet of this species in Deylam coast.