Impacts of Anthropogenic Activities on Fish Diversity of the Ethiopian Rift Valley Lakes: A Review

Abstract

Ethiopia, being a landlocked country since 1993, is fortunate in being blessed with a number of inland water bodies, such as, lakes, rivers, reservoirs, ponds and wetlands including marshes, floodpSain and swamps. These aquatic habitats provide many socioeconomic and a wide range of ecological services. The Ethiopian Rift Valley is part of the Great East African Rift Valley and its floor contains many lakes which arc home for about 30 different fish species. The Rift Valley is also the region where relatively many alien fish species were introduced. Some of the Rift Valley lakes arc used for commercial fisheries, irrigation, recreation, renewable energy supplies and for some industrial purposes. However, many anthropogenic activities like deforestation, habitat destruction, poor soil and water conservation practices, pollution by organic and inorganic chemicals from different sources, introduction of alien species and over fishing arc considered as the major challenges of the area. These activities are directly or indirectly affect the water quality and quantity of the lakes, as well as, water supplying rivers and thereby threatening the fish diversity. Therefore, executing environmental impact assessment before approving any investment projects', -'and enforcing industries to have waste treatment plants (like constructed wetlands) as integral part of the production system, and developing and encouraging ecotourism activities should be taken as an intervention measures to sustain the ecological and socioeconomic benefit of the resource for both the present and future generations.