Sciences marines : recherche et développement

Abstrait

Environmental Impacts of Cage Culture in Lake Victoria, Kenya

Zadock Omach1 *, Winnie Owoko2 , Bruno Odhiambo2 and Taiwo Alare3

Cage farming has become a common practice of rearing fish in marine and freshwater systems worldwide. Fish farming in cages in most East African countries seems to be a new technology, and this came about as a result of the decline in catches of fish around the Lake Victoria basin and the growing demand for protein from fish, which has ultimately resulted in strengthening strategies of boosting aquaculture productions to fill the growing gap of productions from capture fisheries. We conducted an experimental cage culture study at Anyanga, Dunga, Kiwa, and Mulukhoba beaches, Lake Victoria, Kenya, to investigate the impacts of cage aquaculture on the environment. We identified three locations at each beach for sampling. Physio-chemical parameters: Dissolved Oxygen (DO), Temperature, pH, and conductivity were taken. The water samples were then analyzed for nutrients: Total Nitrogen, Total phosphorus, and Ammonium. There were no significant changes in both physio-chemical characteristics of the water and nutrient concentrations. Even though nutrient concentrations were within the recommended ranges, close monitoring of the basin should be encouraged since it is a hyper-trophic lake.