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The black-chinned tilapia (Sarotherodon melanotheron) is a member of the cichlid family, which can be cultured to complement the output from a predominantly catfish aquaculture industry in Nigeria. In order to achieve this objective, it is important to study the bio-ecology of the fish to ascertain the exploitation status and the potential for culture. Fish were collected monthly from February to November 2018 from three sampling sites (Topo, Akarakumo and Ajido) in Badagry Creek, Lagos, Nigeria using gears like cast net, gill nets and traps. The samples were analysed for length-weight relationship, population parameters and feeding preference. The population dynamics of the stock was assessed by the Von Bertalanffy growth model (VBGM) using Electronic Length Frequency Analysis. The parameters of VBGM; asymptomatic length (L∞) and growth coefficient (K) were 20.46 cm and 0.62 year−1, respectively. The growth performance index (Ǿ) was 2.41 and the potential longevity (tmax) was 4.84 years. The total, natural and fishing mortalities were 1.06, 0.68 and 0.38 year−1, respectively. The exploitation rate was estimated as 0.36. The length at first maturity (L50) was 13.79 cm and the length at first capture (Lc) was 12.27 cm. E0.1, E0.5 and Emax are 0.60, 0.38 and 0.70, respectively. The dominant food items in the gut of the fish belong to the algae phylum, Chlorophyta. The study showed that S. melanotheron from Badagry Creek are planktivores and the exploitation rate of the fish is currently close to optimum and should be sustained at this level to prevent overexploitation.

A study was conducted to determine the comparative reproductive, growth performances and nutrient utilization of Clarias gariepinus and its hybrid "heteroclarias" using ovaprim and pituitary extract of male and female C. gariepinus. The experimental broodstocks consisted of 6 female C. gariepinus (2 each were induced separately with ovaprim, male pituitary of C. gariepinus and female pituitary of C. gariepinus), 3 male C. gariepinus and 3 male Heterobranchus bidorsalis. 2 female C. gariepinus induced with synthetic hormone were crossed separately with male C. gariepinus and male H. bidorsalis. A similar crossing was done for the other two sets of female C. gariepinus induced with male and female pituitary glands. The result shows that there was significant difference (P