Release of the western subspecies of chimpanzee in Guinea, West Africa

Summary

The Western chimpanzee (Pan troglodytes verus), Endangered and found in Guinea in greater numbers than anywhere else in its range, was the subject of a rehabilitation-and-release program by the Chimpanzee Conservation Center (CCC), which chose a release site in the Mafou core area of High Niger National Park after screening candidates against habitat quality, distance from settlements, protection status and the presence of wild conspecifics. In June 2008, a socially bonded group of 12 rehabilitated, wild-born chimpanzees, screened for disease and genetically confirmed as the Western subspecies, was released after 7-11 years together at the CCC, supplemented by five more individuals in August 2011; most adults were fitted with VHF/GPS/ARGOS collars ahead of a deliberately minimal in-situ monitoring approach to encourage weaning from human contact. A bushfire destroyed the planned acclimatization enclosure before release, forcing an abbreviated soft-release, and initial scattering of individuals required retrieval missions, during which one male died from anesthesia complications and three uncollared chimpanzees went untracked for a year before being sighted alive among wild chimpanzees; some released animals also learned to cross the Niger River in the dry season, prompting seasonal recapture. By the time of writing, the core group of eight had settled into a stable home range showing wild-comparable reproduction, with new-born survival at 33% despite baboon predation killing two infants, and at least one female had integrated into a wild community. The project rates itself successful, crediting releasing a socially bonded group together, careful pre-release screening, and effective GPS/Argos tracking despite funding constraints.