Reproductive biology of Blackchin tilapia, Sarotherodon melanotheron (Pisces: Cichlidae) from Brimsu Reservoir, Cape Coast, Ghana

Abstract

This study described some aspects of the reproductive biology of Blackchin tilapia (Sarotherodon melanotheron, Cichlidae) from Brimsu reservoir. A total of 457 specimens were sampled using a monofilament gill net of mesh size 25 mm from September, 2009 to September, 2010. Standard length for the species ranged between 7.5 and 17.6 cm, with both males and females having a unimodal modal length of 10.0 to 10.9 cm. The length at sexual maturity (L50) was 11.26 and 11.34 cm for males and females, respectively. The pattern of fluctuation in gonadosomatic index indicates that the species had an extended spawning season starting from February to August. Key words: Sarotherodon melanotheron, reproductive biology, sexual maturity.