Feeding ecology of two sciaenid species (Johnius belangerii and Johnius dussumieri) in the Shatt Al-Arab River, Iraq

Abstract

The food and feeding habits of two sciaenid fish species Johnius belangerii and Johnius dussumieri in the Shatt Al-Arab river, Iraq were studied from November 2015 to October 2016. Fish were caught by gill nets, cast net and electro-fishing. The stomach contents of 220 J. belangerii specimens (122-235 mm total length) and 227 J. dussumeiri (92-225 mm total length) were examined. Results from the stomach contents analysed using the index of relative importance (IRI %) of food items showed that both species were carnivores. The main food items of J. belangeriiwere shrimps (52.9%), crabs (37.9%) and fish (9.2%). The diet of J. dussumeiri composed mainly of shrimps (77.4%), followed by fish (18.4%) and crabs (7.3%). The diet breadth (Bi) values indicate that J. dussumeiri is a high specialist feeder (Bi = 0.196) while J. belangerii was considered non-specialized feeder (Bi = 0.635).