About the Area
The Eastern Arc Mountains consist of a complex of ranges and peaks that are among the oldest in Africa, as are the forest communities of the region. This ecoregion has experienced relatively moist conditions for a very long time because of its close proximity to the Indian Ocean, even as periodic drying trends affected much of Africa.
As is true with most mountainous regions in Africa, this
forest system is isolated from other similar areas by great expanses of lowland habitats. Isolation has produced a high level of endemism with many local species of plants and animals restricted to single mountain ranges.
Altitude, age, soils, rainfall, and distance from the coast all contribute to the unique environment. The current climate of these mountains is much wetter than the surrounding lands, with perhumid (rain every month) conditions and rainfall up to 3,000 mm per year recorded in the eastern Uluguru Mountains.
Many locally endemic species of plants and animals are restricted to single mountain ranges, for e.g. the Usambara Mountains of northeast Tanzania alone have some 50 endemic tree species.