Stock assessment of the big-eye grunt (Brachydeuterus auritus, Val.) fishery in Ghanaian coastal waters

摘要

Annual fishery catch statistics and length data series for Brachydeuterus auritus (Val.) in coastal waters off Ghana for the periods 1974-1997 and 1990-1991 were used to model the growth, mortality rates, indices of abundance and exploitation patterns. Mean population parameters were L-infinity = 23.1 cm (fork length), L-m = 13.7 cm, K = 0.73 yr(-1), Z = 2.67 yr(-1), M = 1.24 yr(-1) and F = 1.43 yr(-1). Yield per recruit analysis showed that excessive fishing effort was being exerted on stocks and a very low length at first capture was observed. Corrective measures are recommended with emphasis on co-operation between fishermen and the government in the decision-making process.