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Population characteristics from samples collected during bottom trawl surveys of 1998-2000 and 2004-2005 were compared to evaluate the success of the management strategies put in place for Nile perch, Lates niloticus and Nile tilapia, Oreochromis niloticus fisheries in Lake Victoria. Data were analysed using FAO-ICLARM stock assessment tool. Length at 50% maturity (Lm 50 ), asymptotic length (L ¥ ) and maximum age (t max ) attained have decreased whereas fishing mortality (F) and growth curvature (K) have increased between the two sampled period. Over 98% of L. niloticus and 60% of O. niloticus caught were immature and the commercial landings indicated a general decline especially in L. niloticus catches in the past few years.The observed changes in population characteristics and decline in catches can be attributed to failure in controlling increasing exploitation in the lake. The number of fishers, boats and gears are on the upward trend. Ban fishing gears like beach seines and small mesh sized gillnets are still prevalent in the lake. Active gillnetting and use of nets that fish the entire water column are increasing in the lake. To sustain the fishery of Lake Victoria, the current situation requires immediate action to be taken. There is a need to re-evaluate the effectiveness of the current management measures with the possibility of adopting new ones that can save the declining fishery. Enactment of new fishery policies should provide for and strengthen the current regulations and their enforcement structures especially in embracing principles of co-management to enhance the whole management process.

Length-frequency data collected from fish landings in the Kenya waters of Lake Victoria were used to estimate the growth parameters, total mortality rate and growth performance index in Oreochromis niloticus . The asymptotic length, (L,,, ) and the ratio of the total mortality rate (Z) to the growth constant (K), were estimated to be 64 .6 cm and 3.219 respectively . K was 0 .254 y -1 , Z was 0 .818 y -1 and the growth performance index (p' = Log lo K + 2 log lo Loo = 3.025, which is rather high as compared to other tilapia populations in natural waters .