A review on the status of some major fish species in Lake Victoria and possible conservation strategies

摘要

AbstractLake Victoria, the second largest freshwater lake in the world, supports an enormous flora and fauna biomass, with a large human population around the Lake. The lake is a source of food (fish), water for domestic use and crop and livestock production, transportation and tourism, among other uses. As a result of these varied uses, human intervention within the lake and its catchment has resulted in several ecological changes in the lake in recent years, with profound effects on its fish resources. One of the most notable changes is the reduction and risk of extinction of some fish species, including the endemic tilapiine species (Oreochromis esculentus and Oreochromis variabilis), catfishes (Xenoclarias eupogon), haplochromines and cyprinids (Labeo victorianus and Barbus altinialis) in the lake. The reduced biodiversity, as well as extinctions within the lake, has been attributed to the introduction of alien fish species (e.g. Nile perch (Lates niloticus) and Nile tilapia (Oreochromis niloticus) into the lake, habitat loss and cultural eutrophication. If left unchecked, these changes will have devastating effects on the lake's resources, as well as to people living around the lake and beyond who depend on the lake fisheries for their livelihood. Thus, there is an urgent need for management measures based on sound scientific research to be implemented in order to curb the loss of ichthyodiversity within the lake, as well as to save the livelihoods of those stakeholders who are either directly or indirectly dependent on the lake.