Lake Naivasha is situated at Latitude 0º 45′ S and Longitude 36º 25′ E, and it is approximately 1890 m.a.s.l. Lake Naivasha basin is among the notably important natural features dotting the floor of Eastern arm of the great rift valley in Kenya. It is a relatively shallow freshwater body and also recognized Ramsar wetlands of international status with a high biological diversity. Its area fluctuates between 120 to 160 km2 depending on rainfall regimes. Lake Naivasha is located in a water deficit area, and hence its water resources are highly valuable to the region. Its water sources support an expanding urban and agricultural population, known for its floriculture and horticulture production. The zone is also known for its great potential in generation of geothermal power on the south-western side of the basin.
Historically the lake is home to several introduced but commercially important fish species. The fishery of Lake Naivasha is based on exotic species namely; Blue spotted tilapia Oreochromis leucostictus, Nile tilapia Oreochromis niloticus, Red-belled tilapia Tilapia zillii, Largemouth bass Micropterus salmoides, Common carp Cyprinus carpio and catfish Clarias gariepinus, with the latter being the most recent invader .Others are riverine longfin barb Barbus paludinosus and Red Louisiana crayfish Procambarus clarkii.
The huge economic potential of the basin has resulted in a fragile ecosystem that faces increasing threats from irrigated agriculture, underground and lake water abstraction, fast expanding urban area with an equal population growth throughout the basin. Increasing sources of pollution and eutrophication of the lake are a concern to all stakeholders. Others include; uncontrolled fishing and bad fishing methods, raw urban effluents discharge into the lake, pesticides pollution, destruction of macrophytes, natural lake level fluctuations and managing introduced alien species.
The station has been involved in various research areas such as:-
- Validation of fish breeding and fishing ground maps through stakeholder’s participatory approach to mitigate resource use and user conflicts on Lake Naivasha;
- Demarcated 4 breeding areas in Lake Naivasha: Crescent Island, Oserian bay, Korongo and Malewa river mouth for fisheries sustainability;
- Determining fishing effort levels and effects on fisheries in Lake Naivasha;
- Monitoring physico chemical parameters in various habitats of the lake.
Current research involves
- Assessing the impact of protection on fisheries productivity;
- Monitoring physical chemical parameters on Lake Naivasha in order to assess levels of pollution;
- Assessing fish stock levels, distribution and abundances in relation to environmental influences on fisheries productivity and management in Lake Naivasha;
- Conducting suitability studies on cage culture of fish in lake Naivasha;
- Studies on fish post harvest management through technology transfers to reduce post harvest losses in lake Naivasha.
Fish Dynamics in Lake Naivasha
Ms. Ednah Waithaka
Kenya Marine and Fisheries Research Institute
Naivasha Research Station
P.O. Box 837 - 20117
Tel +254 (0) 721206953