Fish species diversity and relative abundance in Lake Albert—Uganda

Abstract

Lake Albert is located towards the tip of the western arm of the African Great Rift Valley, between Uganda and the Democratic Republic of Congo. Despite the presence of several predatory fishes, including the Nile perch (Lates niloticus), Lake Albert supports the most diverse commercial fisheries in Uganda with at least 55 species that vary markedly in size. The lake contributes at least 30% of the national fish production. Increased human activity around and within Lake Albert, especially oil and gas exploration, may pose threats to the well being of the lake, its diverse fish communities and its fishery. During 2007, fishery surveys were undertaken using gill-nets and seines in the Uganda part of the lake to identify existing fish species and their critical habitats and provide management recommendations for sustaining the fisheries. Six main habitat types for fishes were identified: shallow river-associated waters; open sandy shorelines; lagoons; large bays; rocky escarpments; and, open-water habitats. Together, these habitats harboured 40 fish species belonging to 12 families. Lagoons, large bays and rocky shores had higher numbers of fish species. Some species rare in most parts of the lake were recovered from the rocky habitats. The shoreline waters contained mostly juvenile fishes. These habitats were considered as natural refugia to fishes in the lake and effort should be made to protect them in order to sustain species diversity in the lake.