The Itombwe Mountains, Eastern Zaire
Few people have ever heard of the Itombwe Mountains. Yet, this massif
supports the largest area of montane forest and bamboo along the Albertine
(Western) Rift Valley, as well as an extremely rich diversity of plant
and animal species, many of which are rare, poorly known and endemic to
the region. Although Itombwe is obviously of considerable conservation
importance, it is a relatively unstudied area. This is a reflection of
its large size, isolation and the problems of gaining access.
From February to June, 1996, a team of biologists conducted a survey of
the larger vertebrates of Itombwe, with a focus on assessing the distribution
and conservation status of the gorilla and chimpanzee. This survey was
lead by Omari Ilambu and funded by the Wildlife Conservation Society
(WCS). I joined the survey team in April for 1 month of field work during
which I focused on the avifauna and primates, particularly the nocturnal
primates. My participation in this survey was supported by Berggorilla
& Regenwald Direkthilfe and Zoo Atlanta. We are now in the process
of analyzing the data and writing up the results. Once this is completed,
some of our more interesting findings as well as an overview of the conservation
situation at Itombwe will be presented in the Gorilla Journal.
Here I provide background information on Itombwe and a brief review of
what was known about the region and its wildlife prior to this survey.
The Itombwe Mountains (1,500-3,475 m) lie on the western side of the
Albertine Rift just off the northwest corner of Lake Tanganyika in eastern
Zaire. About 16,200 km² of Itombwe is above 1,500 m in elevation. Within
this area there are roughly 8,000 km² of montane forest, 1,500 km² of
bamboo forest and 500 km² of montane gallery forest.
The vast interior of Itombwe is largely uninhabited and the few villages
that do exist are along roads and near the edges of the forest. Although
the soils are poor for agriculture, this activity, together with cattle
grazing and mining, continues to expand and damage the forest.
Itombwe is, without doubt, the single richest forest for its birds in
Africa. With 83 montane forest species, it holds about half of the montane
forest bird species in Africa. Of the 36 montane and transition forest
bird species and subspecies endemic to the Albertine Rift, 32 (89%) occur
in Itombwe. Two species of bird are known only from this forest; the Congo
bay owl and Schouteden's swift. The owl is known only from one specimen
obtained 45 years ago. In addition, five Red Data Book birds occur
and nine species which are of special conservation concern. At this time,
Itombwe is considered "preeminent amongst the forests of Africa for
its avifauna" according to Wilson and Catsis and is recognized as
Continental Africa's most important forest for bird conservation.
No detailed mammal surveys have been conducted in Itombwe. The present
list contains seven species of primates, including the eastern lowland
gorilla and the chimpanzee. The type specimen of the eastern lowland gorilla
was obtained from Itombwe in 1908 but the species has never been studied
here at the southern extreme of its range.
Itombwe is one of the key sites for conservation in Africa, yet no part
of it is officially protected. As such, Itombwe is of very high priority
in the protected area needs of the continent.
Thomas M. Butynski
Dr. Thomas Butynski has conducted wildlife research in Africa since 1971. From 1978 to 1993 he studied primates and worked on rain forest conservation in Uganda. Now he works for Conservation International and in addition for the IUCN/SSC Primate Specialist Group. Since 1995 he has made surveys in endangered montane forests in eastern Zaire/Democratic Republic of the Congo.
The survey team