Species Composition of Trawl Shrimp by-Catch in the Fishing Grounds of Northern Persian Gulf (Hormuzgan Province)

The present study aims to recognize dhow shrimp trawl by-catch from Hormuzgan coastal waters (Northeast Persian Gulf). Sampling was performed of 36 hauls among shrimp fishing season in 2012 by using traditionally wooden dhow. The catch composition consisted of 31.64% target species (shrimp, mainly Penaeusmerguiensis) and 68.36% by-catch. The total by-catch was 4622.77kg, which comprised 56 species belonging to 38 families. Species composition of by-catch was 81.08% Teleostei, 0.1% Elasmobranchs and 18.8% Invertebrates.Ulmaridae, leiognathidaeand Mullidaewere the most abundance families with 10.06, 9.97 and 7.73 mean CPUE (Catch Per Unit Effort), respectively. CPUE and Occurrence indexes and catch percentage of species (based on W %) were calculated. By-catch-to-shrimp ratio was computed 2.15:1. Shrimp trawling in t sub-tropical and tropical zones, has huge by-catch and important impacts on fish stocks. Also, we estimated 5728.12 tons of by-catch occurred annually in dhow shrimp trawls in Hormuzgan coastal waters. The investigation of the by-catch showed the large pressure on stocking density of commercial and non-commercial species in the fishing grounds of northern Persian Gulf; which with respect to decrease in stocking density of demersal fishes of Persian Gulf in recent years, has caused increasing concerns.