Estimation of fisheries reference points of the Largehead hairtail, Trichiurus lepturus (Teleostei: Trichiuridae) in Iranian waters of Persian Gulf and Oman Sea

The purpose of this study was to develop a framework to investigate the catch trend and estimation of the optimized catch limit of the Largehead hairtail, Trichiurus lepturus , stock by collecting catch data in the Iranian part of Persian Gulf and Oman Sea. In this research, catch data was collected for 20 years (1997-2018) and the optimized catch limit was estimated using data-limited approach and R Software. The average catch (Ct) for this period was 11550 tonnes (95% confidence interval 11500-11599 tonnes) and it has significantly increased over the past two decades (R=0.68, P <0.05). The intrinsic growth rate (r), carrying capacity (K), maximum sustainable yield (MSY), biomass of maximum sustainable yield (Bmsy), current biomass (B), fishing mortality of maximum sustainable yield (Fmsy) and present fishing mortality (F) were obtained by Catch-maximum sustainable yield (CMSY) models. The results showed that stock of the Largehead hairtail is suffering from over fishing and thereby, reduction of the fishing mortality and exploitation rate and bring back them to the MSY level are essential to save the stock.