Population size of the black colobus monkey Colobus satanas and the impact of logging in the Lope Reserve, Central Gabon

The black colobus monkey Colobus satanas is a threatened species from the central African forests suspected to be vulnerable to habitat disturbance and thus thought to be mainly restricted to primary forest. A survey was carried out in 1995-1996 to estimate the density of black calobus in the primary forest of the Lope Reserve, central Gabon. Combined with the available data on density in the logged part of the reserve, a population of ca. 55,900 colobus was estimated for the whole reserve. No significant differences were found between densities in logged and unlogged forests. Using data on the logging activity that occurred in the reserve, this result was mainly explained by a low rate of extraction (1-2 trees ha(-1)) which did not induce a major change in the forest composition and structure. This suggests that hunting is currently a more important threat to the survival of the species than habitat disturbance. The Lope Reserve is of prime importance for the conservation of this species since it holds the largest population of black colobus known in any protected area. (C) 1998 Elsevier Science Ltd. All rights reserved.