Biomass and CPUA Estimation and Distribution Pattern of Saurida tumbil from Northwest of the Persian Gulf

This paper reports on the results of a trawls survey in 2011 to assess the amount of biomass and Catch Per Unit of Area (CPUA) as well as to determine the distribution pattern of Synodontidae family of demersal fishes (with emphasize on great lizardfish, Saurida tumbil) as one of the most important and commercial fish species in the northwest of the Persian Gulf.  Samples were collected from 65 trawl stations selected at stratified random procedure. The study area was stratified to five strata (A to E) covering the depth layers of 10-20, 20-30 and 30-50 m. The catch rates of CPUA and biomass of lizardfishes were estimated 316.20 kg/nm2, and 2902.1 tons, respectively. The highest value of biomass for  synodontids was recorded in Bordkhoon to Dayer (D and E strata, 1310.6 tones) and in depth layer of 30-50 m in the east of the study area, and the lowest value was estimated for stratum A (west of Khuzestan province) and in depth layer of 10-20 m. On the other hand, the highest CPUA was recorded in stratum D and depth layer of 20-30 m; and the lowest CPUA was recorded in stratum A and depth layer of 10-20 m. It was concluded that stratum D (namely from Bordkhoon to Dayer) harbors the best fishing area as per higher density and distribution of Synodontidae and depth of distribution deeper than 30 m.