Study Area

Lake Tanganyika is the largest (~34,000km2) and oldest (about 10 million years old) of the East African Rift Valley lakes. It is also the second deepest lake on the planet (1470m at its deepest point). The lake basin formed as a consequence of the rifting of the African plate. Many scientists have worked in recent years using Lake Tanganyika as a model for understanding a variety of geological processes that shape lakes and their history. The lake’s tectonics, sedimentary geology and paleoecology are all subjects under active research. The lake’s location, long history, and extensive sedimentary deposits (up to 5km thick in some places!) have the potential to provide us with a record of African climate and environmental change extending back through the entire episode of human evolution.

Over the course of its long and complex geological history, it has been a “hot spot” of evolution, with perhaps 600 species of invertebrates and vertebrates that have evolved in and are restricted to the lake. Cichlid fish, various crustacean,s and gastropods make up the bulk of these endemic species. Today the lake houses incredible species diversity, particularly along its rocky, steep coastlines, where literally hundreds of species of fish and invertebrates may be found at a single locality. Over 1500 species of animals and plants have been described from the lake, making it one of the biologically richest lakes on earth, and new species are being described each year. Superb visibility in these near shore rocky habitats (often over 20m) has allowed researchers to conduct extensive studies on the behavior and ecology of its fish fauna. Multicellular organisms are restricted to the upper 100-200 meters of the lake however, because the deep parts of the lake are devoid of oxygen.

Below Lake Tanganyika’s oxygen-rich surface layer lies a zone of nutrient-rich water. This water mass is periodically mixed by upwelling and turbulence during the windy season into the surface layer, generating very high algal productivity, which in turn supports large zooplankton and fish populations. Although the number of fish species in the open water, pelagic zone of the lake is small in comparison to the coastal rocky habitats, these species are periodically very abundant and form the basis of a very important fishery for the region. Considerable effort by various researchers has gone into understanding the various linkages between climate, the upwelling process, productivity, and the abundance of commercially important fish species.

In recent years Lake Tanganyika, like many other large lakes of the world, has begun to feel the effects of a variety of human impacts, including fishing pressures, an increased rate of sediment accumulation along rocky coasts caused by deforestation and soil erosion in the lake’s watersheds, and climate change. A major focus of current research on the lake (and an area of particular interest to several of the Nyanza Project faculty) is understanding the nature of these impacts and their severity.

As a member of the Nyanza Project team, you will have the opportunity to get involved in some very exciting and important research projects. Literally hundreds of scientific papers have been published on this lake, many of these by the program faculty. As a good starting point for understanding the natural history of this fascinating lake, We recommend the book Lake Tanganyika And Its Life by George Coulter (1991, Oxford Univ. Press) or the CD-ROM Biodiversity: The Great Lakes of Africa by A. Cohen and P. Reinthal (available through the Nyanza Project office).