Moustached guenon  (Cercopithecus cephus)

Classified as Least Concern (LC) on the IUCN Red List (1) and listed on Appendix II of CITES (3). Subspecies: Cercopithecus cephus cephus is classified as Least Concern (LC); Cercopithecus cephus ngottoensis (Ngotto moustached guenon) is classified as Data Deficient (DD); and Cercopithecus cephus cephodes is Not Evaluated on the IUCN Red List (1).

A diminutive species of African forest monkey, the moustached guenon’s name derives from the crescent-shaped, bright coloured patch located between its nose and upper lip. The contrast of this “moustache” with the yellowish-orange cheek tufts and the bare, dark blue skin of the face, gives this species a truly striking appearance. The coat is finely speckled reddish-brown and grey, becoming uniform dark grey towards the extremities, while the throat and belly are whitish grey (2) (4). The tail is considerably longer than the body, and in Cercopithecus cephus cephus and Cercopithecus cephus ngottoensis, mostly coloured blackish-grey, except for the lower part, which is red (2), while in Cercopithecus cephus cephodes it is brown and grey (5).

Occupying western Central Africa, the moustached guenon’s range is bounded to the north by the Sanaga River in Cameroon and to the south and east by the Congo River, except at the south-west corner of its range, where it can be found just south of the lower Congo River, in north-western Angola. There are three recognised subspecies of the moustached guenon, which mostly inhabit different areas. Cercopithecus cephus cephus is the most widespread, being absent only from coastal regions of Gabon and Congo between the Ogooué River and Kouilou-Niari Rivers, where the second subspecies Cercopithecus cephus cephodes occurs. The third subspecies, Cercopithecus cephus ngottoensis, is found in south-western Central African Republic and northern Congo (1)

The moustached guenon principally inhabits lowland tropical rainforest, although it will also tolerate secondary habitats, where scrub or forest is in the process of re-growing after logging, fire or some other major disturbance (1).

A tree-dwelling species, the moustached guenon lives in groups ranging from 4 to 35 individuals, commonly comprising a single male, multiple females and their young. This species is mostly active during the day, foraging in the tree canopy for fruits, seeds and leaves, with insects, eggs and fledglings also taken when available (1) (2). As one of the smaller guenon species, the moustached guenon is particularly vulnerable to predation by birds of prey, such as the crowned hawk-eagle (Stephanoaetus coronatus), and therefore tends to forage where there is dense forest cover (6).

Communication between moustached guenon groups is usually carried out by means of loud booming calls produced by the males (2) (7). These calls may also be useful in mediating the intermingling that frequently occurs between groups of moustached guenon and other guenon species, such as the greater spot-nosed guenon (Cercopithecus nictitans) and crowned guenon (Cercopithecus pogonias) (7). The resulting large, mixed-species groups provide this species with protection from predation, enabling it to utilise open areas where food supplies are more abundant. In return, the moustached guenon provides information to the other species about the location of the best foraging sites (6).

Moustached guenon mating systems are usually polygynous, with the lone male in each group having exclusive breeding access to all the females (2) (8). While breeding may occur all year round (8), in Gabon, births peak from December to February, with the females giving birth to a single young after a gestation period of around six months (4).

The main threats to the moustached guenon are habitat loss through deforestation, and hunting for meat (1) (9). At the present time, these factors do not seem to be having a significant impact on this species, as it remains widespread and, in some parts of its range, is considered common (1). Nevertheless, as deforestation rates and the bushmeat trade continue to grow (10), the moustached guenon may begin to undergo a substantial decline.

The moustached guenon subspecies Cercopithecus cephus cephus and Cercopithecus cephus cephodes are both found in a number of protected areas, and are therefore safeguarded to some extent from habitat loss. Unfortunately, Cercopithecus cephus ngottoensis has not been discovered in any existing protected areas within its range. It is, however, found within the boundaries of the proposed Mbaere-Bodingue Park in the Central African Republic, which will hopefully provide a valuable refuge for this subspecies in the near future (1).

The moustached guenon is listed on Appendix II of the Convention on International Trade in Endangered Species (CITES), which means that all international trade is strictly controlled through maximum export quotas (3). In addition, this species is listed on Class B of the African Convention on the Conservation of Nature and Natural Resources, and therefore legal hunting requires authorisation (1) (11). Despite these controls, the bushmeat trade for the moustached guenon—along with many other species—continues to grow. In order to combat this, a consortium of conservation organisations called the Bushmeat Crisis Task Force has been established. By working with governments, organisations and the general public, they aim to eliminate unsustainable and illegal bushmeat hunting practices worldwide (10).

View information on this species at the UNEP World Conservation Monitoring Centre.

To learn more about conservation issues surrounding the bushmeat trade visit:

• The Bushmeat Crisis Task Force:
  www.bushmeat.org