The Effect of Boat Size on Fish Catches in the Gillnet Fishery of Lake Victoria

The study investigated how the size offishing boat was related to the number and composition of gill nets, fishing grounds and the quantity and composition offish catches. The overall number ofgill nets per boat increased with boat size from 20.9 ± 2.3 nets in 5.0-5 .9 m long boats to 88.6 ± 11.8 nets in 11.0 -11.9 m long boats. The proportion oflarge mesh sizes >127 mm also increased with increase in boat size from 40.4% in 5.0-5 .9 m long boats to 100% in boats >10 m long. The majority oflarge boats 8.0 long fished in offshore waters targeting Nile perch. Their Catches were composed of97.7-100% Nile perch by weight. Boats <8.0 m fished in inshore waters targeting Nile tilapia. Nile tilapia and other fish species excluding Nile perch contributed 31 .0-59.9% oftheir catch by weight. The overall mean fish catch rates increased with boat size from 12.6 ± 1.9 kg in 5.0-5.9 m long boats to 78.2 ± 16.4 kg in 11.0-11.9 m long boats. 73 .6-89% ofNile perch caught by boats <8.0 m long were <50 cm TL, smaller than the legal minimum size allowed for harvest, whereas <17% of ile perch in larger boats were <50 cm TL. The size ofboat has an effect on fish catches and this could be an additional guideline to management ofthe lake' s fishery