Lake Tana - Fauna

Fauna

Since there are no inflows that link the lake to other large waterways and the main outflow, the Blue Nile, is obstructed by the Blue Nile Falls, the lake supports a highly distinctive fish fauna, which generally is related to species from the Nile Basin. About 70% of the fish species in the lake are endemic. This includes one of only two known cyprinid species flocks (the other, from Lake Lanao in the Philippines, has been decimated by introduced species), which consists of fifteen relatively large, up to 1 m (3 ft 3 in) long, Labeobarbus barbs. Eight of these are piscivorous and an important prey is the small Barbus tanapelagius, another endemic of the lake (B. humilis and B. pleurogramma also occur in Lake Tana, but neither is endemic). Other noteworthy endemics are Afronemacheilus abyssinicus, which is the only African hillstream loach, and the tana subspecies of the Nile tilapia.

Lake Tana supports a large fishing industry, mainly involving the Labeobarbus barbs (formerly in genus Barbus), Nile tilapia and sharptooth catfish (a large catfish that is widespread in Africa). According to the Ethiopian Department of Fisheries and Aquaculture, 1,454 tonnes of fish are landed each year at Bahir Dar, which the department estimates is 15% of its sustainable amount.

Among other fauna, the lake supports relatively few invertebrates: There are fifteen species of molluscs, including one endemic, and also an endemic freshwater sponge. Numerous wetland birds, such as great white pelican and African darter, reside at Lake Tana, and it is an important resting ground for many Palearctic migrant waterbirds. There are no crocodiles, but the African softshell turtle has been recorded near the Blue Nile outflow from the lake.