
This geological history of Lake Victoria probably contributed to the dramatic cichlid speciation that characterizes its ecology, as well as that of other African Great Lakes. However, the introduction of exotic fish species, especially the Nile perch, has altered the freshwater ecosystem of the lake and driven several hundred species of native cichlids to near or total extinction. In the 1950s, a proposal to increase fish catches in the lake by introducing the Nile perch (mbutta or Sangara) was adamantly opposed by scientists who feared that the lack of a natural predator for the non-native species would result in the imminent destruction of the lake’s bountiful ecosystem. They were right, and along with the consequences of overfishing as well as pollution caused by rapid human expansion around the shores, Lake Victoria has suffered.
However, Lake Victoria still has more than 200 species of fish, of which the Tilapia is the most economically important. Tanzania’s part of the lake includes Rubondo Island National Park, a beautiful little island that’s home to hippos, alligators and more than 400 bird species. Saa Nane Island’s craggy landscape teems with monkeys, clawless otters, impala, hyrax and rock rabbits. Uganda’s Ngamba Island provides the opportunity to meet chimpanzees brought to the 100-acre island after being orphaned by the bushmeat trade.