Food and feeding habit of Chirocentrus nudus (Swainson, 1839) in Khuzestan coastal waters (Persian Gulf).

摘要

During April to October 2007, a large number of Chirocentrus nudus species were caught in main fishing area of Khuzestan province, namely, Busafe-Liphe and Bahrakan, North of Persian Gulf. The stomach contents of 542 individuals were analysed, in which 324 individuals contained (trace-full) stomachs and 218 individuals empty stomachs. The results of CV index (both sexes) showed monthly random fluctuations in the values. The results of Fp index (both sexes) showed (from 324 prey stomach content) 98% for fish (Sardinella spp. 58%, Ilisha melastoma 16%, Thryssa hamiltonii 14%, Liza klunzingeri 5%, Leioganthus lineolatus 4%) followed by squide (Loligo duvauceli) 2% and crab 1%. The results showed that fish is the main food source for C. nudus followed by sardines. Secondary food source were also fishes (Ilisha melastoma and Thryssa hamiltonii), Liza klunzingeri, Leioganthus lineolatus; Loligo duvauceli and crab is accidental food source. Similar pattern of feeding for C. nudus was observed using CN index. It showed 95% for fish followed by squids (3%) and crabs (2%). Condition factor in both sexes had same pattern from April to July and also in September and October but in August and November were conversed together. Throphic level for C. nudus was obtained 4.7 of 12-100 cm.