The fisheries of Escualosa thoracata have assumed importance in recent years due to its delivery and demand from the domestic consumers. Stock assessment studies pertaining to estimation of growth & mortality parameters and exploitation ratio gives an idea on the fishing intensity exerted on the species. This information proves useful in devising proper management measures. The study has been proposed to investigate the present status of fishing pressure on E. thoracata along Ratnagiri coast. Growth and mortality parameters of white sardine were estimated with length frequency data collected from Ratnagiri coast, India during February 2015 to January 2016 by ELEFAN-I software employing FiSAT. The asymptotic length (L∞) and growth coefficient (K) were estimated to be 135 mm and 1.2 per year respectively by scattergram and 114 mm and 1.0 per year respectively by ELEFAN-I. The value of t0 by von Bertalanffy plot was estimated to be - 0.000012 year. Escualosa thoracata attained a length of 65 mm, 94 mm and 114 mm at the end of 0.5, 1 and 1.5 years of its life respectively. The instantaneous rate of total mortality (Z), natural mortality (M) and fishing mortality (F) were estimated to be 3.56 year-1, 1.25 year-1 and 2.31 year-1 respectively. The exploitation rate (U) was calculated as 0.63 and exploitation ratio (E) was 0.64, clearly pointing toward over-fishing condition for E. thoracata along Ratnagiri coast.
Keywords: Escualosa thoracata, Stock assessment, Asymptotic length, Total mortality