Cephalophus spadix [True, 1890].

Citation: Proc. U.S. Natl. Mus., 13:227.

Type locality: Tanzania, Mt. Kilimanjaro.

The taxonomic record (above) is taken from Wilson and Reeder (1993). Cephalophus spadix is placed in the subgenus Cephalophus [Hamilton-Smith, 1827] along with the other "giant" duikers (C. silvicultor and C. jentinki) and the bay duiker (Cephalophus dorsalis) (Nowak, 1991). Some authors have suggested that Abbott's duiker represents a subspecies, relict ancestral population, or local form of C. silvicultor (see Kingdon, 1982; Wilson, 1987).

Abbott's duiker is a "giant" duiker, weighing 50-60 kg and measuring 100-140 cm in length. Shoulder height is approximately 65-75 cm, and tail length averages between 8 and 13 cm.

Abbott's duiker is a large, stocky duiker with relatively short legs and a thick neck (Kingdon, 1997). The pelage is glossy and dark chestnut brown to black over most of the body, although the underside of the neck and face are paler (Kingdon, 1997; Wilson, 1987; Wilson, 2001). The belly, lower flanks, and insides of the legs are paler brown, and often have a reddish hue (Dorst and Dandelot, 1970; Kingdon, 1982). On the back, just above the root of the tail, some individuals may have a small patch of gray hair; it has been suggested that this may be an ancestral form of the wedge of yellow hairs seen on the back of the yellow-backed duiker (C. silvicultor) (Kingdon, 1982). The untufted tail is tipped with white (Dorst and Dandelot, 1970).

The face is wedge-shaped, with a broad, flat-fronted nostril pad (rhinarium) which hangs slightly over the mouth (Kingdon, 1997). Conspicuous facial markings are absent, but the face is generally pale grey save for the dark brown forehead (Dorst and Dandelot, 1970; Kingdon, 1997; Wilson, 2001). The upper lip is white (Wilson, 2001). Topping the head is a prominent bushy tuft of long hairs; this crest may range in color from pale gray to maroon or chestnut, and often has a strong rufous tone (Dorst and Dandelot, 1970; Kingdon, 1997; Walther, 1990; Wilson, 2001). The ears are relatively short and rounded at the tips, measuring about 10 cm in length; their interior surfaces are pale brown ((Kingdon, 1982; Wilson, 2001).

Both sexes possess a pair of horns (Walther, 1990; Kingdon, 1997). In one female examined by Wilson (2001), the horns were almost buried in the forehead crest such that their tips were only barely visible. Well-developed compared to those of smaller duikers, the horns are long, thin, and slender without any conspicuous thickening at their base (Dorst and Dandelot, 1970; Walther, 1990). Reported horn lengths vary, but encompass the range of 8-12 cm (Walther, 1990; Kingdon, 1997). A male specimen measured by Wilson (2001) had horns 11.2 and 12.1 cm long, with a tip-to-tip distance of 9.0 cm.

Nothing is known on the reproduction of this species, and although Kingdon (1982) reports that no evidence of young offspring was found in September, Wilson (2001) reports a female giving birth shortly after her capture at the beginnging of September, and observing a juvenile in October. Wilson (2001) suggests that, given their rainforest habitat, Abbott's duiker is probably able to breed year-round. Other reproductive parameters are presumably similar to those of the yellow-backed duiker (C. silvicultor).

Prime habitat for this species is dense montane forest and high-altitude swamp, although individuals are also occasionally sighted in higher-altitude scrub and moorland (Kingdon, 1997; Wilson, 1987; Wilson, 2001). In Kilimanjaro National Park, this species is most common at altitudes of 1,300 and 2,700 meters, although sightings have occured at altitudes up to 4,000 meters and (in the Udzungwa mountains) as low as 300 m (Kingdon, 1997; Moyer, Jones, and Rovero, 2008). In the Udzungwa Mountains, records of Abbott's duiker come from forests predominated by Parinari excelsa, Celtis gomphophylla, Bombax rodhagnaphalon, Lettowianthus stellatus, Tabernaemontana pachysiphon, Tarenna pavettoides, Ficus sp., Dracaena manni, Anthocleista grandiflora, and Macaranga capensis (Rovero et al., 2005). This species was photographed in only one of four camera traps set by Rovero et al. (2005), set along a steep northeast-facing slope with low ground cover (grasses and ferns no higher than 40 cm), in a mosaic of open areas and small patches of forest. Kingdon (1982) suggests that the species appears to be restricted to wetter, swampier regions of habitat, most often found on eastern facing slopes.

This duiker is rare across its range; maximum population density in the Udzungwa Mountains is estimated to be 1.3 individuals per km² (Moyer, Jones, and Rovero, 2008). Wilson (2001) provides estimated densities of 1.0 per km² in optimal habitat and only 0.1 per km² in less appropriate regions.

Leopards are known to be a principal predator of Abbott's duiker (Wilson, 2001). Other potential predators include lion and spotted hyena, while young are probably taken by African crowned eagles and pythons (Moyer, Jones, and Rovero, 2008).

Abbott's duiker is thought to be mainly frugivorous, although the diet may also include flowers, green shoots, and herbage (Kingdon, 1997). This species will consume cultivated crops such as sweet potato, bananas, cassava leaves, and cowpeas (Wilson, 2001). Kingdon (1982) records an observation of an Abbott's duiker feeding on the leaves of balsam (Impatiens elegantissima) in September, and Wilson (2001) watched a female feeding on moss growing on rocks near a waterfall in October. One of the first photographs of Abbott's duiker in the wild illustrates a duiker holding an amphibian - possibly a Tanzanian torrent frog (Arthroleptis yakusini) - in its mouth, suggesting that Abbott's duiker, like other duiker species, masy consume animal matter (Rovero et al., 2005).

Very little is known about the habits of this large but shy duiker. It appears to be primarily nocturnal, spending the day resting in dense forest undergrowth or among bracken (Kingdon, 1982). The camera-traps of Rovero et al. (2005) photographed Abbott's duikers primarily at night (19:00-06:00), although one crepuscular observation was also made.

Most observations of Abbott's duikers have been of solitary individuals, which is typical for duikers. Kingdon (1982) states that diagonal pathways along the side of hills are frequently used, with the result that Abbott's duikers may easily snared along these routes. A female observed by Wilson (2001) was seen to raise the hair on her rump when agitated, similar in fashion to the same behavior by the yellow-backed duiker. If pressed, Kingdon (1982) reports that individuals may take to water to escape threats, or may become aggressive if cornered with no chance of escape.

Abbott's duiker is limited in its distribution to Tanzania, where it is presently found on Mount Kilimanjaro, the west Usambara mountains and Udzungwa mountain range in the Eastern Arc mountains, and in the southern highlands (Moyer, Jones, and Rovero, 2008; Wilson, 2001). Small populations may still persist on Mount Rungwe and in Kitulo National Park (Moyer, Jones, and Rovero, 2008).

Countries: United Republic of Tanzania (Moyer, Jones, and Rovero, 2008).

Abbott's duiker is classified as Endangered by the IUCN (Moyer, Jones, and Rovero, 2008), and is not listed by CITES. With an extremely restricted range, Abbott's duiker is vulnerable to habitat loss and degradation as a result of logging and human settlement; hunting (snaring) is also a major threat (Moyer, Jones, and Rovero, 2008). This species, with a total population estimated to be less than 1,500 individuals fragmented into four principal subpopulations, is dependent on protected areas for its survival, notably Kilimanjaro National Park and Forest Reserve and Udzungwa Mountains National Park (East, 1999; Moyer, Jones, and Rovero, 2008).

This species is named after Dr. W.L. Abbott, who collected an adult male specimen on Kilimanjaro between 1888 and 1889; the name of this duiker is is sometimes incorrectly spelled with a single T ("Abbot's duiker") (Kingdon, 1997). The name duiker (pronounced "DIKE-er") is Afrikaans for "diver", describing the escape tactics of many duiker species which involves "diving" into the undergrowth when alarmed. Kephale (Greek) the head; lophus (Greek) a crest, a reference to the conspicuous tuft of hair on the forehead of many duiker species, including Abbott's duiker. The specific name spadix is a Latin word meaning reddish-brown.

Local names

Mende [Kichagga] (Kingdon, 1982)

Vinde or Muvinde [Kihehe] (Wilson, 2001)

Minde [Kiswahili] (Kingdon, 1982)

Binde [Kividunda] (Wilson, 2001)

 

French

Céphalophe d'Abbott (Kingdon, 1997)

 

German

Abbottducker (Kingdon, 1997)