Cephalophus nigrifrons, Gray, 1871

Don E. Wilson & Russell A. Mittermeier, 2011, Bovidae, Handbook of the Mammals of the World – Volume 2 Hoofed Mammals, Barcelona: Lynx Edicions, pp. 444-779 : 730-731

264.

Black-fronted Duiker

Cephalophus nigrifrons

French: Céphalophe a front noir / German: Schwarzstirnducker / Spanish: Duiker de frente negra

Taxonomy. Cephalophus nigrifrons Gray, 1871 ,

Gabon.

C. hypoxanthus , C. rubidus , C. foster , and C. hooki , which were formerly classified as subspecies of C. nigrifons, are here considered full species. Two subspecies recognized.

Subspecies and Distribution.

C.n.nigrifronsGray,1871—SENigeriaandfromSCameroontoNAngola,EtoEDRCongo.

C. n. kivuensis Lonnberg, 1919 — Virunga Volcanoes in Uganda, Rwanda, Burundi, and E DR Congo.

Descriptive notes. Head-body 85-107 cm, tail 10-16 cm, shoulder height 53.5-57. 8 cm; weight 13-16 kg. Females are slightly larger than males. Subspecies nigrifrons is generally larger than kivuensis. Overall color is a deep, glossy chestnut; each hair has a brown base and reddish tip. The pelage is thick, especially in kivuensis. Underparts are scarcely paler than the back in some individuals, but are significantly paler in some populations (e.g. in Republic of the Congo). There is no dark dorsal stripe as seen in many duikers, but a large dark spot or line is present on the chest. The legs are noticeably long; their coloration is dark, becoming almost black at the hooves. In subspecies nigrifrons , the blackish coloration begins at the carpal and tarsal joints; in kivuensis, the entire leg is grayish-black. The shoulders may be darker in some animals. Hooves are elongated and narrow. The tail is long, blackish in color, and has a tuft of dark hair with scattered white hairs at the tip. The face is colored similarly to the body, with a distinctive black blaze that runs continuously from nose to crest, expanding to encompass the entire forehead. The forehead is very black in kivuensis, but is occasionally mixed with chestnut in nigrifrons . A rufousstripe borders each side of the blaze as it passes the eyes. The chin varies from pale reddish or yellow to white, being paler in animals from higher elevations. The well-developed coronal crest is black or reddish. The ears are black, with a white spot on the inside. The horns are 6.5-9. 5 cm long in males (record length is 11-5 cm) and 1:3.5-2 cm in females. Dental formula is 1 0/3, C0/1,P 3/3, M3/5 (x2) =32.

Habitat. [Lowland swampy forests, marshy areas, or forests nearrivers or streams. Long legs and elongated hooves likely adaptations to moving through wet terrain. This species’ range expands during wet seasons when seasonally inundated forests become flooded. Refuge is sought in marshy areas, which may reduce depredation by Leopards (Panthera pardus). Densities of the Black-fronted Duikerin the Ituri Forest, DR Congo, are approximately 1-6 ind/km?.

Food and Feeding. Primarily frugivorous, but consumes more vegetation (leaves and stems) than other sympatric duikers. Stomach content analyses in Gabon revealed a dietary composition of 71-6% fruit, 27-8% leaves and stems, 0-62% fungi, and trace amounts of flowers and animal matter. Most fruits consumed are 1-3 cm in diameter; these are typically eaten whole. Preferred fruit species include Plagiostyles africana, Klainedoxa gabonensis, and Ongokea gore. Leaf stems and animal matter are eaten at greater frequency during wet seasons. In the mountains of Rwanda, preferred food species include Impatiens spp., Cerastium spp., Stellaria sennii, Geranium spp., Droguetia iners, Mentha aquatica, Viola eminii, Tylophoropsis heterophylla, Trifolium spp., and Plantago lanceolata . Lichens such as Usnea sp. and mosses are also consumed; the duikers may stand on their hindlegs to pull down hanging lichens. Black-fronted Duikers have been observed consuming ants by licking the ground crossed by ant columns. This species rarely enters agricultural areas.

Breeding. There is very little specific information available for this species. Maximum life span (as recorded in captivity) is over 17 years.

Activity patterns. Diurnal, butlittle other specific information available for this species.

Movements, Home range and Social organization. Black-fronted Duikers frequently use pathways in dense vegetation alongside marshy areas. They may disperse far into swamps during the day to forage, especially in the dry seasons (January-February and June-July), and return to the shelter of forests at night. When startled into flight, they make loud thumping noises (it is not known whether these are vocalizations or from the large inguinal glands). The Black-fronted Duiker has been observed swimming across rivers. This species is typically solitary, but is occasionally seen in pairs (suggested to be stable associations). Home ranges are marked with preorbital gland secretions and loud whistle-like calls;it is not known whether territoriality is involved.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Blackfronted Duiker continues to thrive in remote and inaccessible areas, but is threatened by bushmeat hunting in regions of human habitation. The total number of Blackfronted Duikers (including populations of the Mount Kenya Duiker, C. hooki, the Itombwe Duiker, C. hypoxanthus, the Mount Elgon Duiker, C. foster, and the Rwenzori Duiker, C. rubidus ) is estimated at 300,000 animals.

Bibliography. Dubost (1984), East (1999), Grubb & Groves (2001), IUCN/SSC Antelope Specialist Group (2008h), Lydekker (1914), Plumptre (2001), Powell & Grubb (2002), Thomas (1892b), Weigl (2005), Wilson (1987, 2001).

Figures

On following pages: 259. Western White-bellied Duiker (Cephalophus leucogaster); 260. Uele White-bellied Duiker (Cephalophus arrhenii); 261. Red-flanked Duiker (Cephalophus rufilatus); 262. Natal Red Duiker (Cephalophus natalensis); 263. Harvey's Duiker (Cephalophus harveyi); 264. Black-fronted Duiker (Cephalophus nigrifrons); 265. ltombwe Duiker (Cephalophus hypoxanthus); 266. Rwenzori Duiker (Cephalophus rubidus); 267. Mount Elgon Duiker (Cephalophus fosteri); 268. Mount Kenya Duiker (Cephalophus hooki)

Subspecies and Distribution. C.n.nigrifronsGray,1871—SENigeriaandfromSCameroontoNAngola,EtoEDRCongo. C. n. kivuensis Lonnberg, 1919 — Virunga Volcanoes in Uganda , Rwanda , Burundi , and E DR Congo .