The Eastern Arc chain of mountains contains extraordinarily high biodiversity with more than 100 endemic amphibians, reptiles, mammal and birds, and perhaps as many as 1,500 endemic plants. The East Usambara Mountains are on block within the Eastern Arc and are of exceptional importance for the conservation of biological diversity, generally ranked among the top 5 forest sites on the African continent in terms their biological values.
More than 100 species of plants and animals are endemic to the 413 km2 of remaining forests in the East Usambaras. In the vertebrates 78 endemic and near-endemic species are present.
The Amani Nature Reserve and the Nilo Forest Reserve have been demonstrated as having the highest biodiversity values within the East Usambaras, but all the remaining forests are extremely as rare and endemic species are found at all altitudes.
The Derema corridor area of forest has not been surveyed in detail for its biodiversity values, but is likely to possess many of the East Usambara endemic species as it ranges in altitude from lowland (c.300 m) to sub-montane (around 1,000 m).
Five villages, Kisiwani, Msasa IBC, Kwezitu, Kwemdimu and Kambai, lie around the edges of the Derema corridor and in 2002 there was 1,567 farmers with cardamom plantations within the Derema forest.
Villages have also used the land within the forest for cultivation of black pepper and banana, and they extracted firewood and non-timber forest products. Actions by the Forestry and Beekeeping Division (FBD) stopped cultivation within the Derema forest in 2002 and a process of compensation and provision of alternative livelihoods and farmland has been going on ever since. More than $2.5 million has been paid to the affected farmers over the past 5 years, from the Tanzanian Government, Finnish Government, Global Conservation Fund and the World Bank.
This process is being concluded in 2008 – and farmers are being assisted with income generating projects and alterantive farming land on the Misozwe Sisal Estate in the lowlands. The final gazettment process will lead to the Derema forest becoming either a separate Forest Reserve, or a part of the Amani Nature Reserve. This has still to be concluded.
Resettlement Action Plan for Farm Plots Displaced for Biodiversity Conservation in the Derema Forest Corridor (2006). Ministry of Natural Resources and Tourism, Forestry and Beekeeping Division.
Newmark W.D. (1992) Recommendations for wildlife corridors and the extension and management of forest reserves in the Eastern Usambara Mountains, Tanzania. Final Report, East Usambara Catchment Forest Project.