Longitudinal patterns of fish community structure in the Shatt al-Arab River, Iraq

الملخص EN

The fish assemblage and some ecological variables for three sites in the Shatt Al-Arab River, Iraq during 2010 and 2011 was used to assess the effect of environmental conditions on longitudinal seasonal variations in fish species abundance and distribution patterns.

A total 1460 fishes belonging to 40 species and 19 families, all belonging to Osteichthyes, were captured using seine net.

The fish fauna consisted of nine native, 25 marine and six alien species.

Cyprinidae, the dominant family, was represented by ten species.

Carassius auratus was the most abundant species numerically comprising 20.3 %, followed by Tenualosa ilisha (13.3 %) and Liza subviridis (8.7 %).

Salinity gradient showed significant differences among the sites and ranged from 0.8 ‰ to 7.6 %.

Results suggested the present of three ecological fish guilds in Shatt Al-Arab River, each representing unique species associations, habitat characteristics, and spatial fish distributions.