Size structure, size-weight relationship and condition factor of Coptodon dageti and Sarotherodon galilaeus, two Cichlids from Lake Selingue, Mali

Abstract

The present contribution aims to study the size and weight structures, the size-weight relationship and the condition factor of Coptodon dageti and Sarotherodon galilaeus from Lake Sélingué. Fish samples, collected during the rainy season, were measured and weighed. The relationship between the standard length (Ls) and the total length (Lt) is given by the equation of the line Lt = 1.267Ls + 3.025 for Coptodon dageti and Lt= 1.301Ls - 0.720 for Sarotherodon galilaeus. That between the eviscerated weight (Pe) and total weight (Pt) is Pe = 0.869Pt+0.047 for Coptodon dageti and Pe = 0.892Pt-1.117 for Sarotherodon galilaeus. The allometric growth decreases both for Coptodon dageti (b=2.84) and for Sarotherodon galilaeus (b=2.98). The values of the condition factor are 4.90±0.49 for Coptodon dageti and 2.31±0.19 for Sarotherodon galilaeus, reflecting good body condition in both species. The results can be used as reference data in fisheries development programs for Lake Sélingué.