Upper Guinea Rivers and Streams - A Global Ecoregion

Much of the original forest cover has been lost to agriculture

About the Area
Wet conditions have existed more or less permanently over evolutionary time in the Upper Guinea ecoregion, allowing species to survive here when dry conditions dominated other portions of West Africa.

The Guinean mountain range (> 1,500 meters elevation) and its many waterfalls and rapids further limited the dispersal of aquatic species in the coastal basins into other West African basins.

These isolated conditions have resulted in high species endemism; for example, this ecoregion has several fish species adapted to the turbulent, fast-flowing waters of the coastal rivers and streams.

Local Species
This ecoregion is distinguished by two endemic genera of crabs and dozens of endemic fish species. The many small river basins that drain into the Atlantic are also unique in their high fish richness by area.

The fish species especially adapted to turbulent waters include Epiplatys njalaensis, E. olbrechtsi, and West African catfish (Chrysichthys maurus).

The endemic Mount Nimba otter shrew (Micropotamogale lamottei), which inhabits montane streams on Mount Nimba, is endangered. The imperiled Pygmy hippo (Choeropsis liberiensis) inhabits the forested watercourses of the lower coastal basins. A number of frogs are restricted to this ecoregion, such as Astylosternus occidentalis, Hyperolius occidentalis, Cardioglossa aureoli, and Bufo cristiglans.

Threats
Serious problems from deforestation, mining of iron ore and diamonds, and the political instability in Liberia and Sierra Leone have had a huge impact on the natural state of this ecoregion.

Resources
• NationalGeographic.com