Structural Diversity of Fish Communities in the North Part of Shatt Al-Arab River North of Basrah off Al-Qurna.

The study was conducted from December 3013 to November 2014, at Al-Qurna North of Basrah. The study aimed to investigate the diversity structure of fish communities in the North part of Shatt Al-Arab river. Three stations were selected, North Qurna, confluence of Al-Sweeb river in Shatt Al-Arab river and at Al-Shaffi area. Samples were collected by using seine net, fixed net, draft net, cost net and electrofishing. A total of 18342 fish belonging to 32 species of Osteichthyes relate to 13 families were captured. Cyprinidae is the dominant family, represented by 13 species. The total number of individuals were collected from North of Qurna 2870 fish consisted of 22 species, 6983 fish fauna from Al-Sweeb comprising 27 species and 8489 from Al-Shaffi belong to 27 species. The highest abundance species in the collected area were Liza abu, Carassius auratus, Tilapia zillii and Oreochromis aureus (36.71, 31.55, 9.84 and 5,63% respectively). Diversity index (H) ranged 0.92-1.89, Richness (D) 0.95-2.59 and Evenness (J) 0.39-0.78 for study area, the entire similarity 52.91% according to Jaccared similarity index. [ABSTRACT FROM AUTHOR]