By James Wolstencroft (2006)
The following is a substantially modified and updated account based on Bird Life International’s information for the West Usambara IBA (Important Bird Area – Tanzania 071). This brief account will form the foundation for a new birder’s resource for the Usambaras, to be stored on maweni.com which is physically housed at Maweni Farm, near Soni, a birder-friendly tourist lodge in the heart of the West Usambaras.
The West Usambaras are a steep-sided mountain block, oriented from south-east to north-west and rising from the margins of the coastal lowland and central plateau at 400–800 m. They have one main internal drainage system via the Umba river which flows eastwards from the north-eastern edge of the mountains. There are a few high ridges that approach an altitude of 2000 – 2200m; the highest peak is Sungwi at 2327m.
To the north lies Mkomazi Game Reserve to the north-west the Pare mountains, to the south-east the East Usambara and to the south the Pangani river valley which separates the mountains from the dry Acacia–Commiphora woodland of the Maasai steppe.
The western scarp is characterized by very impressive sheer cliffs, often with remnant forest along the rim and extending down the many stream-eroded valleys into drier woodland at the base of the hills.
The plateau has been extensively cultivated, especially around Lushoto, the district capital. Cultivation has increased significantly during the last few decades, especially noticeable in marginal land and along river valleys.
The surviving forest is very fragmented into many small blocks; typically clinging to rocky hill tops or on the steepest slopes. Only two extensive swathes remain: firstly Shume – Magamba (11,567 ha) and secondly Shagayu (6,223 ha), both of which are under considerable pressure from a rapidly increasing human population at their perimeters.
The Forest Division has listed 27 Forest Reserves for Lushoto District. However, many of these reserves are very small and others remain production forests.
Those that are significant, or are thought to be so, are Shagayu (6,223 ha protected), Shume – Magamba (11,567 ha protected), Balangai West (1,074 ha), Kisimagonja (1,440 ha, badly degraded), Mjusu (3,670 ha, badly degraded), Ndelemai (3,554 ha), Bombo West (3,565 ha), Bumba Mavumbi (1,056 ha), Lutindi (2,176 ha), Mafi Hill (2,671 ha) and Ndolwa (1,173 ha). Only for Shagayu, Shume-Magamba and Mafi is there anything like a complete bird inventory.
In addition, there are two privately-owned forests of major ornithological importance, included in the Important Bird Area: Ambangulu Tea Estate, which is virtually all that remains of the lower altitude forest; and Mazumbai which protects ca 600 ha of near pristine montane and upper montane forest. A little-used earthen road contours through the forest at an elevation of between 1500 – 1600 m providing superb opportunities for birding.
The most localized bird, occurring mainly at higher elevations for example along the ridge in Mazumbai forest, is a shy ground-haunting robin known as the Usambara Akalat, Sheppardia montana which is endemic to the West Usambaras. However the rarest and most threatened bird is almost certainly the Usambara Weaver Ploceus nicolli which seems to occur only at very low density and chiefly along the lower margins of the remaining forests – precisely those that are under the greatest pressure from an inexorable rise in local human needs.
From a base at Maweni Farm lodge visits can be made to the Shume-Magamba forest reserve, to the nearby Ndelemai FR and to the magnificent and well-protected forest at Mazumbai. To the latter Maweni Farm can arrange both transport and excellent value overnight accommodation undertaken in conjunction with the Sokoine University of Agriculture forest research station which is situated there.