Dietary ecology of the Portunus segnis (Forskal, 1775) in the coastal waters of Hormozgan Province, Iran

In this study, the feeding habits of blue swimming crab (Portunus segnis) in the Northeast Persian Gulf were investigated. A total of 722 specimens were collected using bottom trawl. The samples were transferred to the laboratory in order to further analysis after freezing. All individuals were dissected and their stomach was removed. The results showed the vacancy index of stomach (CV) was 34.5. This finding indicated that this species is a gluttonous crab. Also the analysis of their feeding habits showed that this species is carnivorous. The main items included crustaceans, fishes and mollusks. Their diet varied seasonally. Crustaceans were more important in summer whereas fishes and mollusks were more important during autumn and winter, respectively. The crustaceans included shrimps and other crabs. The dominant mollusks were the bivalves such as common name Marcina hiantina, Circentia callipyga, Tellina sp., Cardita bicolor and gastropods Cerithium erythraeonese, Atys sp. There were significant differences in feed items occurrence frequency between sexes.