266.

Rwenzori Duiker

Cephalophus rubidus

French: Céphalophe du Rwenzori / German: Ruwenzori-Schwarzstirnducker / Spanish: Duiker del Ruwenzori

Other common names: Ruwenzori Red Duiker

Taxonomy. Cephalophus rubidus Thomas, 1901,

Ruwenzori district, E. Africa.

Treated by some authors as a subspecies of C. mgrifrons (and formerly of C. natalensis). This affinity with C. nigrifrons is generally accepted, although genetic material extracted from a museum specimen tooth indicates an affinity with C. ogilbyi, C. weynsi, and C. callipygus. Monotypic.

Distribution. Endemic to the Rwenzori Mountains in W Uganda. Distribution is not believed to overlap with other duikers in the C. nigrifrons group as once thought; records of C. rubidus from Rwanda likely refer to the Black-fronted Duiker subspecies (C. maigrifrons kivuensis); this latter species is absent from the Rwenzoris.

Descriptive notes. Head—body 75 cm, tail 10 cm, shoulder height 45 cm; weight 15 kg. The rich rufous fur is thick, dense, and “slightly woolly” over most of the body; the hair on the neck is long and coarse. The underparts are much paler than the back, with a zone of gradual transition between the colors; the axillary and inguinal regions are white. An indistinct grayish-brown dorsal stripe is present from the neck to the base of the tail, created by a zone of red-tipped but basally gray hairs. Elsewhere on the body the underfur is white. The sides of the neck are particularly bright rufous, and the hairs on the neck do not show any reversal in growth patterns. The hindlegs are almost black in color (including the hocks); the forelegs are the same reddish color as the body, but possess dark brown markings at the joints, giving them a similar dark appearance. The tail is bushy and mostly black on the dorsal surface; the underside and tip are white. The head color is not significantly different from the rufous of the body, except for a black or dark brown blaze that stretches from muzzle to crown. The chin is bright white. The horns, presumably present in both sexes, measure 8-9 cm in length. Dental formulais10/3,C0/1,P 3/3,M 3/3 (x2) = 32.

Habitat. Afro-alpine and subalpine zones in the Rwenzori Mountains, recorded at elevations of 1300-4200 m. The montane forest habitat is characterized by Hagenia woodland and bamboo zones at lower elevations. Dense herbaceous vegetation is avoided. The Rwenzori Duiker is reported to feed in boggy, densely overgrown, or wooded areas, but is sometimes seen in open meadows or on rocky slopes. It is often seen close to the snow line. Densities have been estimated at 5-22 ind/km®.

Food and Feeding. There is no specific information available for this species. Diet likely resembles that of the Black-fronted Duiker in the Rwandan mountains.

Breeding. There is no information available for this species.

Activity patterns. Reported as primarily diurnal, but weather conditions (especially rain) may cause activity to shift to night. Activity patterns may thus vary with seasons. Foraging forays into open meadows typically occur around dawn and dusk.

Movements, Home range and Social organization. There is little specific information available for this species. Believed to be territorial, with boundaries marked with feces. Presumably solitary like other similar duikers.

Status and Conservation. Classified as Endangered on The IUCN Red List (as C. nignfrons rubidus). The Rwenzori Duiker was subjected to extreme hunting pressure from the 1960s to the 1990s, but now receives some protection within Rwenzori Mountains National Park. The total population is estimated to be a few thousand individuals.

Bibliography. East (1999), Grubb & Groves (2001), IUCN/SSC Antelope Specialist Group (2008h), Kingdon (1982, 1997), Thomas (1901), Wilson (1987, 2001).