Cercopithecus roloway (Schreber, 1774)

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 : 680

61.

Roloway Monkey

Cercopithecus roloway

French: Cercopitheque roloway / German: Roloway-Meerkatze / Spanish: Cercopiteco roloway

Other common names: Roloway Guenon

Taxonomy. Simia roloway Schreber, 1774 ,

Guinea (West Africa).

Intermediate features between C. roloway and C. diana have been found near the Sassandra River, there the orange tones of the buttocks and inner thighs become deeper, but there is no intermediacy in the beard or brow band. C. rloway and C. diana comprise the diana species group. Monotypic.

Distribution. SE Ivory Coast and SW Ghana, possibly Togo.

Descriptive notes. Head-body 50-60 cm (males) and 42-45 cm (females), tail 85 cm (males) and 70 cm (females); weight 5-2 kg (males) and 3-9 kg (females). The Roloway Monkey closely resembles the Diana Monkey (C. diana ) in appearance. Four main differences distinguish them: length and shape of beard (a much longer, pointed, and entirely white beard c.75 mm in length on the Roloway Monkey ); color of inner thighs and pubic region (creamy-white to orangey-yellow on the Roloway Monkey vs. orangered on the Diana Monkey ); prominence of a band of white hair across brow (more prominent and extending further on sides on the Roloway Monkey ); and thickness of the white thigh stripe ( the Roloway Monkey's is narrower than Diana Monkey's).

Habitat. Primary and some secondary rainforest, gallery forest, and semi-deciduous forest near rivers. The Roloway Monkey has been much less intensively studied than the Diana Monkey , so fewer details of its habitat preferences (as well as ecology and behavior) are known, but they are presumed to have similar adaptations. The reported distribution of the Roloway Monkey also suggests that it may be able to occupy slightly drier and more seasonal forests than the Diana Monkey. The Roloway Monkey is a high-canopy specialist like the Diana Monkey.

Food and Feeding. The only field study of the diet of the Roloway Monkey was done by S. Curtin in Bia National Park, western Ghana, in 1976-1977. The diet comprised pulp ofripe fruits (31%), insects (25%), seeds of ripe fruits (22%), leaf buds (7%), flower buds and flowers (6%), and unripe fruit (5%); seeds of unripe fruits, mature leaves, root nodes, and bulbs were eaten occasionally (less than 1%). In the dry season, the pulp of mature fruit (especially of lianas and vines) was the most important food, followed by insects and the seeds of ripe fruits. In the wet season, ripe fruits and insects were equally important. During the study, seeds (large and black with a red aril and especially rich in oils) of Pycnanthus angolensis (Myristicaceae) and small immobile insects on branches and foliage, most particularly in the large legume Piptadeniastrum africanum ( Fabaceae ), were the most important food items in terms of the time dedicated to eating them. Both trees were common at Bia . Diets of Roloway and Diana monkeys can vary greatly among populations, years, and even neighboring groups. Diets of Roloway Monkeys at Bia contained 24-3% ripe and unripe seeds (77% of them from Pycnanthus and Funtumia elastica, Apocynaceae ) in contrast to the diets of Diana Monkeys from three field studies that contained only 0-11-6% seeds. Pycnanthus , like figs, produces fruits asynchronously, but it provides small quantities of fruits and seeds piecemeal over many months, unlike the mast fruiting of figs. The insect portion of the diet of Roloway Monkeys was similar to that of Diana Monkeys.

Breeding. There is no information available for this species.

Activity patterns. Like the Diana Monkey, Roloway Monkeys are active, high canopy specialists. They are extraordinarily agile, foraging among terminal branches of emergent canopy trees and making acrobatic leaps to catch insect prey.

Movements, Home range and Social organization. Projected similarities between Roloway and Diana Monkeys suggest that groups of Roloway Monkeys contain one adult male, several adult females, and young. Only one social group of the Roloway Monkey has been carefully studied: the group had 14-15 individuals (one adult male, six adult females, and young). It traveled 1-3 km/day in a home range of 190 ha. The group traveled further per day in the dry season than the wet season. Groups of Roloway Monkeys probably defend territories, although no specific information on territorial behavioris available.

Status and Conservation. CITES Appendix I. Classified as Endangered on The IUCN Red List (as C. diana roloway ). The Roloway Monkey is listed as Class A in the African Convention on the Conservation of Nature and Natural Resources. It originally occupied forests from the Sassandra River in western Ivory Coast to the Pra River in Ghana, and possibly extending into Togo. It was not found in Togo in recent primate surveys there. The most recent surveys indicate that it is more threatened than has been previously recognized; individuals have been reported at only one site, Tanoé Forest in Ivory Coast. If this is correct, the Roloway Monkey should be recognized as one of Africa’s most endangered primates, and it should accordingly be updated to critically endangered. Unconfirmed reports suggest that it might still hang on in very small numbers at Ankasa in Ghana; a thorough survey of Ankasa should be a high priority. The main threats to the Roloway Monkey include hunting and habitat degradation and loss. The loss of tall mature forest to logging and agriculture has not only degraded preferred habitat but also opened the forest up to commercial hunting for bushmeat. The relatively large size of the Roloway Monkey and the value ofits meat and skin make it a preferred game species. A couple of decades ago, the Roloway Monkey inhabited several parts of West Africa, including Krokosua Hills, Yoyo River, Boin River, and Draw River forest reserves, Ankasa Game Reserve, and Foret Classée de Yaya in Ivory Coast, and Dadieso Forest Reserve and Tanoé Forest in Ghana. Because of high human density around these areas, the Roloway Monkey's habitat has suffered one of the highest recent rates of deforestation in the world. Prior to this, Ghana's 300km* Bia National Park (the only site where Roloway Monkeys have been studied) was downgraded to a game production reserve. Logging concessions were granted in 1977, and the small remaining park area did not receive adequate protection; no Roloway Monkeys occur there anymore. The Roloway Monkey has been steadily extirpated from both unprotected and protected areas, and it is nearing extinction.

Bibliography. Curtin (2002), Curtin & Olson (1984), Gatti (2010), Gonedelé Bi et al. (2008), Groves (2001, 2005b), Grubb et al. (2003), Kingdon (1997), Magnuson (2002), McGraw (1998a, 2007), McGraw & Oates (2007), Napier (1981), Oates (1988b, 1999, 2011).

Figures

59. Dryas Monkey (Cercopithecus dryas), 60. Diana Monkey (Cercopithecus diana), 61. Roloway Monkey (Cercopithecus roloway), 62. De Brazza’s Monkey (Cercopithecus neglectus), 63. Mona Monkey (Cercopithecus mona), 64. Campbell's Monkey (Cercopithecus campbelli), 65. Lowe's Monkey (Cercopithecus lowei), 66. Crowned Monkey (Cercopithecus pogonias), 67. Wolf's Monkey (Cercopithecus wolf), 68. Dent's Monkey (Cercopithecus dent)

Distribution. SE Ivory Coast and SW Ghana, possibly Togo.