Stock Assessment Indicators for Sustainable Exploitation of Chrysichthys walkeri in Lake Volta, Ghana, West Africa

Abstract

The biological indicators of Chrysichthys walkeri (Claroteid catfishes) in lake Volta were investigated for their sustainable management. A total of 846 samples were collected from the lake from March to December 2020. The recorded total length of the fish samples was analyzed using TropFishR. The von Bertalanffy parameters including asymptotic length (L∞), growth rate (K), and growth performance index (Φ) were estimated as 28.88 cm, 0.42 per year, and 2.54 respectively. Mortality parameters were calculated as total mortality rate (Z) = 2.56 per year, natural mortality rate (M) = 0.91 per year and fishing mortality rate (F) = 1.65 per year. The exploitation rate (E) was 0.64. From the study, it was concluded that the population of the species C. walkeri from the Lake Volta is overexploited. There is the need to ensure continuous monitoring of fishing effort to ensure the sustainable exploitation and management of C. walkeri.