A large tract of near-pristine
Afromontane forest has been found in Angola’s
Namba Mountains,
tripling the amount of this habitat that was thought to survive in Angola. The
site meets the criteria for a new Important Bird Area (IBA), holding one
globally threatened species, and assemblages of restricted range and
biome-restricted bird species.
Afromontane forest is the most
localised and threatened habitat type in Angola. By the early 1970s, only
200 ha was estimated to remain, mainly at the Mount Moco IBA (85 ha), and
perhaps in the Namba
Mountains, where most
forest was thought to be degraded by logging.
Mount Moco
and the Namba Mountains lie within the Western Angola
Endemic Bird Area, which includes four restricted-range species associated with
Afromontane vegetation. Two Afromontane endemics of global conservation
concern, Endangered Swierstra’s Francolin Pternistis
swierstrai and Near Threatened Angola Cave-chat Xenocopsychus ansorgei, are
found at Mount Moco, but the francolin is now uncommon there. The Data
Deficient endemic Grimwood’s Longclaw Macronyx
grimwoodi is also found at Moco. Several other Afromontane
specialists have been found only there or at one or two other sites in Angola, and
face a serious threat of extirpation from the country.
Angola’s Afromontane forest and
thicket holds 20 species, subspecies or populations of conservation
significance, isolated and distinct from other Afromontane “centres of
endemism”, the nearest of which is over 2000 km away. All 20 were recorded at
Moco prior to 1970, but several are now rare or absent.
A team including members of the University of Jos,
Nigeria, and Percy
FitzPatrick Institute of African Ornithology, South
Africa, travelled to the Namba Mountains
in July 2010, to establish the extent and condition of forest, and to conduct
bird surveys. Due to the difficulty of traversing the terrain (dense
undergrowth, steep slopes, an abundance of large boulders, and limited trail
access) they were confined to exploring a single forest patch and surrounding
grasslands and mountain slopes, an area of 24 ha.
They recorded 89 bird species, 56
of them in or adjacent to forest, including a significant population of
Swierstra’s Francolin, and the other Afromontane specialists that are now hard
to find at Mount Moco.
On their return, they examined
satellite images from Google Earth, which indicated that there is currently
around 590 ha of forest in the Namba mountains, more than trebling the previous
national estimate.