Cercocebus agilis, A. Milne-Edwards, 1886

Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Cercopithecidae, Handbook of the Mammals of the World – Volume 3 Primates, Barcelona: Lynx Edicions, pp. 550-755 : 651-652

24.

Agile Mangabey

Cercocebus agilis

French: Mangabey agile / German: Olivmangabe / Spanish: Mangabey agil

Taxonomy. Cercocebus agilis Milne-Edwards, 1886 ,

Congo-Brazzaville, Poste des Ouaddas, Oubangui-Congo confluence.

There are fairly well separated dark and light morphs of C. agilis , with the former being much more common. Individuals tend to be larger in the western part ofits distribution. Albinism has been reported. Monotypic.

Distribution. SE Cameroon, SW Central African Republic, N DR Congo (N of the Congo River, from Ubangi River to the Ituri Forest and the Semliki River), NE Gabon (E of the Ivindo River), and the N of the Republic of Congo (across the Sangha River). A single record from Equatorial Guinea was possibly a misidentification.

Descriptive notes. Head-body 51-65 cm (males) and 44-55 cm (females), tail 56— 76 cm (males) and 45-60 cm (females); weight 8.8-10.2 kg (males) and 4.3-6.2 kg (females). The Agile Mangabeyis a large, slender mangabey, with relatively long limbs, a long muzzle, and a tail that is longer than its body. Fur is short and fine, being brownish-olive to gray-olive (speckled with yellow) above, but the median dorsal zone tends to be darker. Underside (as far as the chin and including inner surfaces of limbs) is pale grayish-white and not speckled. Hands and feet of the Agile Mangabey are very dark brown, almost black. Tail becomes lighter distally, is light below, and sometimes ends in a whitish tuft. Face is black with pale (not white) eyelids, and cheeks are white. Crown is somewhat dark, nearly always with a whorl of hair often exposing a pale patch of skin. Males are much larger than females. Adult males produce a loud, long-distance call, a “whoop” followed by a rumble that can be heard from up to a kilometer away.

Habitat. Mostly seasonally flooded forest and rainforest near rivers. In contrast, Agile Mangabeys in Dzanga-Sangha Forest Reserve, Central African Republic, spend most of their time in terra firma-mixed forest and are never observed along the Mondika River or in swampy forest along the Ndoki River. As.in other capped mangabey species, the Agile Mangabey spends most ofits time on the ground and in the lower forest strata (0—10 m).

Food and Feeding. Agile Mangabeys eat mainly fruits and seeds (up to 76%), supplemented with underground plant parts, herbs, pith, shoots, and some animal prey (including young duikers, Cephalophus).

Breeding. Female Agile Mangabeys have a menstrual cycle of ¢.30 days. A single young is born after a gestation of c¢.6 months. Interbirth intervals average 21 months if the infant survives. As in other mangabey species, females develop conspicuous perineal swellings when approaching ovulation. Post-conception swellings are also likely.

Activity patterns. Agile Mangabeys are diurnal and semi-terrestrial.

Movements, Home range and Social organization. The home range size of a group of Agile Mangabeys at Dzangha-Sangha was ¢.303 ha. Another group in Gabon used 198 ha. Daily movement at Dzanga-Sangha was 1155 m (range 390-1985 m). The group size was 8-22 individuals, but groups of 40 and more than 100 individuals have also been observed. Mean group size in the Gabon study was 10-5 individuals (7-18). Groups usually contain several adult males and females. Densities in Gabon were 6-7— 12-5 ind/km?, but lower densities have been recorded elsewhere.

Status and Conservation. CITES Appendix II. Classified as Least Concern on The [UCN Red List. The Agile Mangabeyislisted as Class B in the African Convention on the Conservation of Nature and Natural Resources. It is threatened by habitat loss caused by deforestation. It is also locally hunted for meat and persecuted for crop raiding. Studies are needed to assess the impact of hunting on the Agile Mangabey. It is known or presumed to occur in a number of protected areas: Minkebé National Park in Gabon; Dja Biosphere Reserve in Cameroon; Dzanga-Sangha Forest Reserve, Ngotto Classified Forest, and Dzanga-Ndoki and Mbaéré-Bodingueé national parks in the Central African Republic; Garamba National Park in DR Congo; and Nouabalé-Ndoki and Odzala national parks in the Republic of the Congo.

Bibliography. Arlet & Molleman (2010), Bermejo (1999), Blom et al. (1992), Boehm & Mayhew (2005), Booth (1958a), Brugiere et al. (2005), Carroll (1986), Chapman & Legge (2009), Colyn (1988, 1991, 1994), Colyn & Deleporte (2002), Daegling & McGraw (2007), Depierre & Ole (1976), Fleagle & McGraw (2002), Gautier-Hion (1975, 1978), Gautier-Hion & Brugiére (2005), Gautier-Hion & Gautier (1976), Gautier-Hion et al. (1999), Gautier & Gautier-Hion (1969), Gilbert et al. (2009), Groves (1978, 2001, 2005b), Grubb (2006), Grubb et al. (2003), Hart & Thomas (1986), Hart et al. (1996), Hill (1974), Jolly (2007), Kingdon (1997), Knights et al. (2008), McGraw & Fleagle, (2006), Mitani (1990), Muchaal & Ngandjui (1999), Quris (1973, 1975, 1976, 1980), Sabater Pi & Jones (1967), Shah (2003), Smith & Jungers (1997), Swedell (2011), Thomas (1991), Usongo & Fimbel (1995) Vanthomme et al. (2010), Wilkie & Finn (1990).

Figures

23. Tana River Mangabey (Cercocebus galeritus), 24. Agile Mangabey (Cercocebus agilis), 25. Golden-bellied Mangabey (Cercocebus chrysogaster), 26. Sanje River Mangabey (Cercocebus sanjer), 27. Sooty Mangabey (Cercocebus atys), 28. White-naped Mangabey (Cercocebus lunulatus), 29. Red-capped Mangabey (Cercocebus torquatus), 30. Mandrill (Mandnrillus sphinx), 31. Drill (Mandrillus leucophaeus), 32. Gray-cheeked Mangabey (Lophocebus albigena), 33. Rusty-mantled Mangabey (Lophocebus osmani), 34. Johnston's Mangabey (Lophocebus johnstoni), 35. Ugandan Crested Mangabey (Lophocebus ugandae), 36. Northern Black Crested Mangabey (Lophocebus aterrimus), 37. Southern Black Crested Mangabey (Lophocebus opdenboschi), 38. Kipunji (Rungwecebus kipunji)

Distribution. SE Cameroon, SW Central African Republic, N DR Congo (N of the Congo River, from Ubangi River to the Ituri Forest and the Semliki River), NE Gabon (E of the Ivindo River), and the N of the Republic of Congo (across the Sangha River). A single record from Equatorial Guinea was possibly a misidentification.