Size: 260 sq km (172 sq miles).
Location: Northern Tanzania, 300 km (190 miles) northwest of Arusha.
Lake Natron is a saline lake located in Northern Tanzania, close to the Kenyan border, in Tanzania's Great Rift Valley. The lake is quite shallow, less than three meters (10 feet) deep, and varies in width depending on its water level. Lake Natron is a fascinating, almost surreal location. Due to salt-loving microorganisms that live in the alkali salt crust of the lake's surface, the lake is often red or pink in colour. The lake is also the only breeding site for 2.5 million Lesser Flamingoes, because the caustic environment is a barrier against predators trying to reach the flamingoes' nests.
The color of the lake is characteristic of those where very high evaporation rates occur. As water evaporates during the dry season, salinity levels increase to the point that salt-loving microoranisms begin to thrive. These salt-loving organisms include some cyanobacteria - tiny bacteria that grow in water and make their own food with photosynthesis as plants do. The red pigment in the cyanobacteria produces the deep reds of the open water of the lake, and orange colors of the shallow parts of the lake. As salinity increases, so do the number of cyanobacteria, and the lake can support more Lesser Famingo nests. These flamingoes flock along saline lakes in the region, where they feed on Spirulina (a blue-green algae with red pigments).