Roloway Guenon ( Cercopithecus diana roloway ) and White-Naped Mangabey ( Cercocebus atys lunulatus ) Prefer Mangrove Habitats in Tanoé Forest, South-Eastern Ivory Coast

Abstract

There are three primate taxa which have the same range in West Africa (eastern Ivory Coast and western Ghana): Miss Waldron’s red colobus Piliocolobus badius waldronae, the Roloway guenon Cercopithecus diana roloway and the white-naped mangabey Cercocebus atys lunulatus. They were previously listed as critically endangered; however, Cercocebus atys lunulatus was recently downgraded to endanger. A series of surveys have been conducted since the early 1990s in the tropical forests of Ghana and Ivory Coast to survey thesee taxa. In 2006, these studies led to the conclusion that the Tanoe forest, south eastern Ivory Coast should be considered a top priority site for primate conservation in West Africa. From February 2008 to March 2008; and in March 2009, we carried out field surveys in the Tanoe Forest over 22 days to gather updated distribution information to assess the conservation status of all diurnal primate taxa occurring in that forest, with special focus on the red colobus, Roloway guenons and white-naped mangabeys. During walk surveys of 429.3 km by three teams, we failed to observe any red colobus monkey. Diana roloway guenons were encountered at 0.10 groups/Km in the flooded forest vs 0.65 groups/ km in mangroves and white-naped mangabeys were encountered at 0.07 groups/km in the flooded forest vs 0.50 groups/Km in mangroves. Both these taxa were significantly more frequently encountered in mangroves compared to flooded forests. The high observation rate of Roloway monkey and white-naped mangabey in mangroves seems to indicate an adaptive strategy developed by these taxa to avoid hunting pressure. In addition, with its abundant foliage and the permanent presence of water throughout the year, mangrove offers food for monkeys.