An assessment on the catch efficiency of gillnets for Talang queenfish (Scomberoides commersonnianus, Lacepède, 1801) stocks using selectivity model in coastal waters of Hormozgan province

In this study, the catch efficiency of Talang queenfish (Scomberoides commersonnianus) was examined for the surface, mid-water and bottom drift gillnets using cumulative probability distributions of retention in coastal waters of Bandar Abbas and in the western part of Hormozgan province during the years 2014-2015. For this, the transverse morphometric data for girths in three positions of the fish body such as Opercular girth (OP), girth at the beginning of first dorsal fin (D1) and girth at the beginning of second dorsal fin (D2) along with fork length have been collected for four gillnets in different stretched mesh sizes of 101, 114, 165 and 171 mm. Results from the analysis of covariance (ANCOVA) showed that girth at D1 is considered to be the maximum girth of the species (P<0.05). Fish were tangled in the nets depending on meh size. Unlike the 165 and 171 mm nets, in mesh sizes of 101 and 114 mm the selectivity curves were not fitted to the length frequency distribution. Base on the selectivity curve, the optimal length of S. commersonnianus for the nets of 101, 114, 165 and 171 mm was obtained as 44, 52, 66 and 76 cm respectively. It seems that nets with meshes of 165 and 171 mm are suitable to harvest S. commersonnianus stocks aimed at capturing mature fish in order to approach to sustainable exploitation level, whereas it is needed to do further study on filed for any suggestion on the nets of 101 and 114 mm.