The Tanoé Swamps Forest is located within the original distribution area of the Miss Waldron red colobus (Piliocolobus badius waldronae), the diana roloway (Cercopithecus diana roloway) and the white-napped mangabey (Cercocebus atys lunulatus), three monkey species that have been classified by IUCN (2002) among the 25 most threatened monkey of the world. These monkeys are the most threatened monkeys of West Africa. Surveys conducted in their supposed distribution area for more than a decade highlighted an advanced degradation of habitats, an intensive poaching and a subsequent decimation of the primate fauna illustrated by the local extinction of the above mentioned three monkey species from most of the surveyed forests including national parks. The Tanoé Swamps Forest is an exception in this dramatic context since this forest still houses the Diana roloway, the white-napped mangabey, and other monkeys of conservation concern such as the Geoffroy’s colobus (Colobus vellerosus) and the olive colobus (Procolobus verus).

During a recent survey (February-March 2008) a team from the Swiss Centre for Scientific Research (CSRS) in the Tanoé Swamps Forest, vocalizations of the Miss Waldron’s red colobus which has never been snapped alive were heard, despite having previously been suspected extinct. In addition, the RASAP-CI / CSRS team encountered at least 6O troops of diana roloway and 30 troops of white-napped mangabeys in the Tanoé Swamps Forest.

This is extraordinary since these monkeys are critically endangered with decimated or extinct populations elsewhere

The Tanoé Swamps Forest is no doubt the only forest on earth where important numbers of these monkeys can be found. The forest is certainly the only one on earth where there is a viable population of the Diana roloway and there is still a chance for rediscovering the Miss Waldron’s red colobus.

Colobe de Geoffroy (Colobus vellerosus) Copyright Anh Galat-Luong IRD

Off note is that except the Miss Waldron’s red colobus, all the above mentioned monkeys of conservation concern occur in most parts of the Tanoé Swamps Forest.