Growth, Mortality and Exploitation Rates of Sarotherodon melanotheron in the Dominli Lagoon of Ghana
Abstract
Sarotherodon melanotheron population of Dominli Lagoon in the Western Region of Ghana was studied for its growth and mortality parameters as well as exploitation rate. The study generally aimed at providing basic information necessary for the assessment and management of the fish stock in the lagoon. Using FiSAT programme, estimates of the prominent growth and mortality parameters of S. melanotheron were: L∞ = 20.48 cm, SL and K = 0.97yr‾¹. Total, natural and fishing mortalities of the population were determined as 3.86 y‾¹, 2.02 y‾¹ and 1.84 y‾¹, respectively. The growth estimates and the maturity-length ratio (≈ 0.7) suggested that the S. melanotheron population was not stunted. The fast growth rate and continuous recruitment exhibited by S. melanotheron were indicative of its suitability for culture. The present exploitation rate (0.48) indicates that the black-chinned population is not overexploited. The Y′/R and B′/R curves as well as all-year-round recruitment show that the current exploitation rate could be maintained for sustainable and rational exploitation of the black-chinned tilapia stock.
