Comparison of fish species diversity in Dalaki and Helleh Rivers of the Persis basin in Bushehr Province

Fish species diversity in Dalaki and Helleh Rivers which are parts of the Persis basin of Bushehr Province, was investigated from January 2013 to February 2014. Twelve species belonging to 6 families (Cyprinidae, Sisoridae, Mastacembelidae, Gobiidae, Mugilidae and Sparidae) were identified. The results indicated that Cyprinidae has the most frequencies in Dalaki River and Mugilidae has the most frequencies in Helleh River. Mastacembelidae and Sisoridae families in Dalaki River have the least frequencies and Mastacembelidae and Cyprinidae families have the least frequencies in Helleh River. Capoeta saadii with 33% in Dalaki River and Planiliza abu with 36% in Helleh River have the most frequencies, Mastacembelus mastacembelus and Glyptothorax silviae with 2% in Dalaki River and finally M. mastacembelus and Cyprinus carpio with 1% in Helleh River have the least frequencies. Based on the Shannon species diversity index, the most diversity of species in Dalaki and Helleh Rivers was found to be in July and August 2013.