Rediscovery of Bouvier’s Red Colobus in the Southern Republic of Congo

Abstract

In 2016, we carried out a wildlife survey in the Lefini Reserve and the Lesio-Louna Reserve in the south of the Republic of Congo. The aim was to identify the relative abundance and distribution of large mammals, and the trends since the previous survey in 2009. The last time that Bouvier’s red colobus Piliocolobus bouvieri had been recorded in the area was in the early 1970s. All subsequent surveys had failed to find it, and the species was considered to have been locally extirpated. During the 2016 survey, whilst travelling along a river in the most remote area of the Lesio-Louna Reserve, we saw a group of them in a riparian forest. Hunting is by far the principal threat to these monkeys, and their persistence in this area of Congo is likely due to the combination of active protection of the Lesio-Louna Reserve and the inaccessibility of the area where they were found. Access is only possible on foot or along the rivers; the nearest roads and villages lie 45 km to the east and 65 km away to the south, and the main navigable rivers are patrolled by reserve staff. Maintenance of protection of the reserve is key to the continued survival of the species.