Fishery of sciaenids with some observations on the biology and stock assessment of Johnieops sina (Cuvier, 1830) exploited along the Malabar coast

Abstract

Sciaenids form an important demersal finfish resource exploited off Malabar coast. They are caught by trawls, gillnets and ringseines and are landed throughout the year. The average annual catch was 2452 t during 2001-2008. The landings fluctuated but showed a decline. Though several species supported the sciaenid fishery, Johnieops sina was the dominant species contributing more than 58% to the catch. In the fishery, the length of J. sina ranged from 62 to 229 mm. The length at first maturity was 114 mm for males and 122 mm for females. The spawning period is prolonged with two peaks, one in September-November and another in February-April. The male – female sex ratio was almost equal in the catch. The length-weight relationship was estimated as W=0.000046658 L 2.8313. The estimated asymptotic length (L∞) and annual growth coefficient (K) of J. sina were 268 mm and 0.45, respectively. The respective annual total, natural and fishing mortalities were 3.63, 1.10 and 2.31. The spawning stock biomass is more than 30% of the stock at its unexploited level.