Gray Cheeked Mangabey

Maximum longevity: 36 years (captivity) Observations: One wild born female of the *aterrimus* subspecies was still living in captivity at an estimated age of 36 (Richard Weigl 2005).

The grey-cheeked crested mangabey usually feeds high in the forest canopy, on a diet of fruit, seeds and nuts, as well as buds, shoots, leaves and flowers (2) (7) (11). Invertebrates, such as ants, ant larvae and caterpillars, are also taken, with individuals often breaking open hollow branches or rotten wood in search of this prey, and adult males have also occasionally been recorded preying on small mammals (11) (12). Large incisors allow the grey-cheeked crested mangabey to crack open hard nuts, and cheek pouches enable food to be collected to be eaten later (4) (7). Grey-cheeked crested mangabey troops typically average around 15 individuals (5) (8), led by a dominant male (2). Breeding appears to occur year-round (2) (6), with a single young born after a gestation period of nearly six months (2) (4) (5). Female grey-cheeked crested mangabeys show a conspicuous pink sexual swelling when they are ready to mate (2) (7). The lifespan of the grey-cheeked crested mangabey varies according to diet; groups that consistently feed on hard nuts wear their teeth down faster and die sooner than those with softer diets (2). In captivity the grey-cheeked crested mangabey may live for over 32 years (6).

The grey-cheeked crested mangabey is listed under Appendix II of the Convention on International Trade in Endangered Species (CITES), meaning that international trade in this species should be carefully monitored and controlled (3), and is also listed under Class B of the African Convention on the Conservation of Nature and Natural Resources, which only permits the grey-cheeked crested mangabey to be killed or captured with special authorisation (14). The species also occurs in some protected areas, including Dja Faunal Reserve in Cameroon, a World Heritage Site (13) (15). However, hunting pressure and habitat loss may be resulting in local declines, and the likely upgrading of the subspecies to full species level means that the status and conservation of each form of grey-cheeked crested mangabey needs urgent reassessment (1) (10).

The grey-cheeked crested mangabey is a large, tree-dwelling monkey, with long limbs, a long, ruffled tail which is longer than its body, and a distinctive mantle of longer, lighter-coloured hair over the neck and shoulders (2) (4) (5). The body is black, with a browner underside (5) (6) (7), while the shoulder mantle varies in colour both between individuals and between locations, ranging from grey to fawn or brown (2) (7). As the common name suggests, the cheeks are usually grey, and the face is black and only very thinly haired. The top of the head bears a tufted crest of longer fur (2) (5) (7). Females are slightly smaller and more slender than males (2) (4), though less noticeably so than in other mangabey species (7) (8). Since facial and visual displays are of limited use in the dense forest canopy, the grey-cheeked crested mangabey relies less on these than other mangabey species, and also lacks the pale upper eyelids which other mangabeys use to enhance facial signals. Instead, the grey-cheeked crested mangabey is highly vocal, communicating with a range of grunts, barks, chuckles, screams, and a distinctive “whoop-gobble” call given by the adult male. This loud call is amplified by specialised air sacs in the male's throat and clearly advertises the presence and location of his troop (2) (7). To date, three subspecies of grey-cheeked crested mangabey have been recognised (1) (7), which vary greatly in body and mantle colour, and in the crest of fur on the head (2) (7) (9). However, the taxonomy of the species is currently being revised, and it is likely that the subspecies will be elevated to full species status in the near future, with those in Uganda constituting a fourth species, Lophocebus ugandae (9) (10).

Both primary and secondary rainforest, as well as riverine and swamp forest (1) (2) (5). Although mainly a lowland species, the grey-cheeked crested mangabey can also be found in montane forest, at elevations of up to 1,600 metres (1) (2).

The grey-cheeked crested mangabey is found in central Africa, from Nigeria south to Angola, and east to Uganda, Rwanda and Burundi (1) (2) (7). Lophocebus albigena albigena occurs in southern Cameroon, east to the Central African Republic, and south to northeastern Angola. Lophocebus albigena osmani is found further north, in Cameroon and southeastern Nigeria, and Lophocebus albigena johnstoni is found in Burundi, Democratic Republic of the Congo and Rwanda. The proposed species Lophocebus ugandae is confined to western Uganda (2) (7) (10).

Classified as Least Concern (LC) on the IUCN Red List (1) and listed on Appendix II of CITES (3).

The grey-cheeked crested mangabey is threatened by habitat loss due to logging and clearing of forests for agriculture (1) (13). Although this species can use secondary forest, it is thought to be mainly dependent on intact primary forest, and may be less adaptable to habitat changes than other forest monkeys (13). Grey-cheeked crested mangabeys are also hunted for bushmeat, particularly in Equatorial Guinea and Cameroon (1) (13), and in Uganda are killed for raiding crops, although this behaviour is only thought to happen in areas where forests have recently been felled (13).

The grey-cheeked mangabey (Lophocebus albigena), also known as the white-cheeked mangabey, is an Old World monkey found in the forests of Central Africa. It ranges from Cameroon down to Gabon. The grey-cheeked mangabey is a dark monkey, looking in shape overall like a small, hairy baboon. Its thick brown fur is almost black in its forest home, with a slightly rufus/golden mane around the neck. The sexes are similar, with the males slightly larger than the females.

The grey-cheeked mangabey lives in a variety of habitats with the forests of Central Africa, it is generally thought to live in either swamp or primary forests, in some areas it has also been found in secondary forest as well. Some authors in the past have considered the species to be restricted to the forest canopy, however more recently habituated troops have been observed on the forest floor collecting food. It feeds primarily on fruit, particularly figs, taking other fruits seasonally, as well as shoots, flowers and insects.

The grey-cheeked mangabey lives in groups of between 5 and 30 individuals. The groups have either a single male or (more usually) several, without a single dominant male. Young males leave the troop once they are adult and join other troops, whereas the females stay in the troop of their birth. If troops become too large they may split. Confrontations between troops are rare, as this mangabey will usually avoid other troops. Their territories cover several square miles of forest, and can both overlap with other troops and shift over time.

Three subspecies of this mangabey were previously recognized. In 2007, Colin Groves elevated them all to species level, splitting one (johnstoni) into two species.