Stock assessment and estimation of biological parameters of Tigertooth croaker (Otolithes ruber) in the northern Persian Gulf, Bushehr and Khozestan

In the Persian Gulf waters, the sciaenid species, Otolithes ruber, plays an important role in the commercial fishery and to this reason, the resources are under catch pressure. Stock assessment and population dynamics parameters of this species were studied in Bushehr and Khozestan waters from April 2012 to March 2013. In the present study, 4203 of specimens obtained from gillnet landing places and length frequency data (fork length) were recorded. Length frequency ranging from 11 to 50 cm. The parameters of the von Bertalanffy growth equation (males and females combined) for asymptotic length (L∞) was 52.5 cm and instantaneous growth coefficient (K) was 1.1 year−1. The instantaneous rates of total mortality (Z), fishing mortality (F) and natural mortality (M) were 3.42, 1.85 and 1.57 per year, respectively. Estimated parameters of precautionary target (Fopt) and limit (Flimit) biological reference points were 0.79 and 1.04 respectively. The values of two parameters Fopt and Flimit were lower than fishing mortality (F) that showed this species is over exploited in the Bushehr and Khozestan waters by gillnet fishery.