Temporal and Spatial Variations of Finfish Bycatch of Cutlassfish Trawl Fisheries in Bushehr and Hormozgan Waters, the Northern Persian Gulf

The spatial and temporal variations of finfish bycatch assemblages cutlassfish trawl were compered in two fishing area (Hormozgan and Bushehr waters). Data were collected on board of commercial vessels in the fishing grounds of Trichiurus lepturus since May 1st 2009 to November 2010. There was a significant difference in the bycatch assemblages between Bushehr and Hormozgan fishing grounds. SIMPER showed that six species contributed 65% of the biomass of the bycatch assemblages between two fishing areas: Nemipterus japonicus (30.5%), Ilisha melastoma (12.5%), Saurida tumbil (8.5%), Argyrops spinifer (6%), Dasyatis bennetti (4.5%) and Netoma thalassinus (4%). Differences appeared for the temporal structures of bycatch assemblages in fishing grounds of Bushehr. SIMPER showed that eight species contributed 69.3% to the dissimilarity of the biomass of the bycatch assemblages between fishing seasons. These species were S. tumbil (17.3%), I. melastoma (16.3%), N. japonicus (13.3%), Carangoides malabaricus (17.2%), Rachycentron canadun (6.3%), Upeneus sundaicus (3.5%) D. bennetti (3.5%) and Epinephelus coioides (3.2%).