Lake Nakuru, Kenya Photograph by David Olson   Eastern Africa: Northern Tanzania, on the border with Kenya Flooded Grasslands and Savannas   1,000 square miles (2,600 square kilometers) -- about the size of Rhode Island Relatively Stable/Intact

· Salty Lakes in a Rift
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
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Salty Lakes in a Rift

If you were to descend into the eastern arm of the Rift Valley in Kenya and Tanzania, you might assume that this dry landscape would support little life. Yet this area includes extraordinary saline (salty) lakes that are home to endemic, salt-tolerant fish and provide important habitat for migratory and breeding birds. These are seasonal saline wetlands--and when it rains the dry "pan" landscape transforms into shallow lakes filled with specialized algae, invertebrates, and fish that are patrolled by waterfowl such as flamingoes and ducks.

Special Features

The unusual saline and soda lakes that make up this ecoregion are fed by hot and cold springs and underground seepage. Some of the hot springs are nutrient rich, adding salts to the lakes. Lakes fed by seepage may be made up of fresh and saline waters that form separate layers, with the lighter fresh water on top. This ecoregion is an important source of life-giving water in an area that receives little rainfall.

	Flamingoes are not born pink, but they acquire their unusual coloring from pigments in their food--small "sea-monkey"-like invertebrates. It takes one to two years for a juvenile to turn from a grayish color to the pink that we most associate with flamingoes.

Wild Side

The highly salty conditions in these lakes support very few submerged plants--only cyanobacteria, diatoms, and green algae seem to flourish. Salt marshes and freshwater wetlands are found where the lake edges are able to support a gradient of specialized salt-adapted plant communities. Vast flocks of lesser and greater flamingos congregate to feed and breed on these lakes. The water they take in is filtered through comb-like ridges lining the inside of their bills--and the invertebrates are then filtered out from the water. As many as 1.5 million migrant wetland birds can be found on one lake in particular--Lake Nakuru. This is quite impressive considering it is only a shallow soda lake.

Cause for Concern

Pollution from sewage, pesticides, and heavy metals threaten the water quality of several of the lakes. Grazing, mining, and logging have altered large portions of the landscape within the catchments of these lakes. Agriculture is also common, and in areas with less salt content the water used for irrigation competes with water needed for the natural functioning of the lakes.

For more information on this ecoregion, go to the World Wildlife Fund Scientific Report.