• W. O. ABDUL
Keywords: Recruitment pattern, stock assessment, Tilapia zillii, Ogun state.


A study was carried out on the stock parameters, recruitment pattern, and probability of capture of T. zillii in Ogun estuary, Ogun State, Nigeria using length-frequency and catch-at-length data. The fish stock was assessed using the methods of ELEFAN 0- III of the FiSAT II software. Results showed that the stock has a continuous recruitment pattern. L25, L50 and L75 were 13.82cm, 15.50cm and 17.19cm respectively. Fish population decreased with increase length class. Average mortality rate was 1.16/year, and exploitation rates were lower in length class 11-12cm to 26-27cm and large size, 34-35cm, and equal or greater than optimum in others. Steady biomass also increased with length class until 24-25cm. The fishery would attain MSY if the present effort level is raised by 1.6.



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