Usambaras, West

Region: Tanga
Type: E - Potential connectivity of important habitats.
Threat: Critical - probably less than 3 years remaining.
An example Forest Restoration Scenario for the West Usambara Mountains
An example Forest Restoration Scenario for the West Usambara Mountains

An example Forest Restoration Scenario for the West Usambara Mountains

An example Forest Restoration Scenario for the West Usambara Mountains (modified from Halperin, 2002, p. 74).

Description

The West Usambaras (2,200 km2) is one of the most important mountain ranges in the highly species-diverse Eastern Arc Mountains. Only 13% of the land area remains forested and this forest is highly fragmented owing to severe logging.

Two FRs in this area, the Baga FR and the adjacent Mazumbai Forest lie only 2-3 kms from the Kisima-Gonja FR. They are separated by the Mkolo River catchment with Sagera and Mayo village boundaries that lie in between them.

Increased connectivity of forest patches would greatly enhance sustainability of the ecological services and biodiversity values of this landscape. A study by J.J. Halperin developed a number of potential forest restoration scenarios, taking into account data on ecological potential, environmental need, and social acceptability of different interventions among communities.

Wildlife

Home to many endemic African violets and 10 new species of lichen, and 29% of tree species are endemic.

There is great endemism of amphibians and reptiles, 8 out of 15, and 14 out of 37 species respectively. Of 81 bird species, 5 have very restricted ranges and 1 or 2 strictly endemic. One species of hyrax is believed to be endemic.

Many of the larger mammals have been hunted out of the West Usambaras, leaving only squirrel species, black and white colobus, Sykes monkeys, and very few duikers.

Threats

Small scale subsistence agriculture converting forest to maize, beans, cassava and banana fields and cash crops for local towns.

The increased area of forest edge resulting from fragmentation of forest also introduces pathways for invasion of exotic species which may reduce indigenous plant diversity. The invasive exotic Lantana sp. is frequently seen along forest patch edges in the West Usambaras.

Trial areas for community forest development exist within the watershed, and people’s attitudes to reforestation is positive as indicated by questionnaires, but these areas are mostly for fast growing exotics.

References

Halperin J. (2002) Reforestation planning in the West Usambara Mountains. Unpublished M.Sc. thesis, North Carolina State University.