Population Age Structure and Stock Assessment of Reeve’s Croaker Chrysochir aurea (Richardson, 1846) Along West Bengal Coast of India

Abstract

The age structure, growth, mortality, and exploitation status of the Chrysochir aurea stock in West Bengal coast, India, were assessed. A sample of 618 specimens with total lengths ranging from 124 to 417 mm were collected from commercial trawlers between September 2021 and September 2022. The length-frequency distribution was analysed using the FiSAT II tool. The growth parameters asymptotic length (L_∞), catabolic coefficient (K), and initial condition factor (t₀) were determined to be 435.23 mm, 0.26 yr^-1, and -0.309 years, respectively. The total (Z), natural (M), and fishing (F) mortality rates were estimated at 1.09, 0.35, and 0.74 yr^-1, respectively. A consistent recruitment trend was seen throughout the year, with two peaks, one from February to May and the other from July to November, with a length at first capture (L_C) of 177.95 mm. The current exploitation level (E_now) and maximum exploitation level (E_max) were calculated at 0.68 and 0.60 indicating overexploitation of the stock along the coast. The yield was projected to be 160.826 t at the current fishing level (f = 1.0) and 164.866 t at the maximum fishing level (f = 0.9). To create a sustainable fishery in the future, a reduction in fishing effort is suggested.