The Role of Tilapia Species (Family Cichlidae) in the Fishery of Three Upland, Deep Reservoirs of Sri Lanka

Abstract

The fish catches of three upland reservoirs, namely, Kotmale, Victoria and Randenigala reservoirs, were studied for periods of 8, 18 and 9 months, respectively. Tilapia species formed 60-70 % of the catch of all three Reservoirs. Three species of tilapia, namely, Oreochromis mossambicus, O. niloticus and Tilapia rendalli were present in Victoria and Randenigala reservoirs but the last species was not caught in Kotmale reservoir. The three species formed, respectively, 50.8 %. 49.2 % and 0 % of the tilapia catch of Kotmale reservoir, 71.5% 26.6% and 1.9% of that of Victoria reservoir and 96.2%, 2.6% and 1.2% of that of Randenigala; reservoir. The relative abundance of the three species in the three reservoirs is discussed in relation to that of the three species in other reservoirs in Sri Lanka.