Bovidae
Author
Don E. Wilson
Author
Russell A. Mittermeier
text
2011
2011-08-31
Lynx Edicions
Barcelona
Handbook of the Mammals of the World – Volume 2 Hoofed Mammals
444
779
book chapter
58516
10.5281/zenodo.6512484
67b52095-db4b-43f8-a661-4aced0511111
978-84-96553-77-4
6512484
240.
Cape
Blue Duiker
Philantomba monticola
French:
Céphalophe bleu
/
German:
Kap-Blauducker
/
Spanish:
Duiker
azul de El
Cabo
Taxonomy.
Capra monticola Thunberg, 1789
,
Cape
Colony.
P. monticola
was formerly a parent taxon that included all blue duikers (all members of the genus
Philantomba
east of the
Cross River
,
Nigeria
) as subspecies. The present taxonomy has divided this group into ten distinct species, and the
Cape
Blue Duikeris now restricted to the southern coast of
South Africa
. Monotypic.
Distribution.
S
South Africa
(from the city of George,
Western Cape
, E through
Eastern Cape
).
Descriptive notes.
Few body measurements specific to the Cape Blue Duiker (as defined here) are available, but head-body c.
60 cm
, tail ¢.
8 cm
; weight c¢.4-5 kg. Skull size 1s similar to the
Zimbabwe
Blue Duiker (
P. bicolor
), and body size likely follows. In color, the Cape Blue Duiker is rather paler than the
Zimbabwe
Blue Duiker; the overall color is a pale gray or fawn. The rump is not particularly dark, and the haunches have only a slight reddish tinge; there is very little difference in color between these two areas (cf. the
Zimbabwe
Blue Duiker). The underparts are whitish. All four legs are bright rufous in color. The tail is only slightly darker than the dorsum. The face is colored similarly to the body; although the cheeks and underside of the jaw are paler. Simple, spiked horns may be present in both sexes; they are longer than in the
Zimbabwe
Blue Duiker, averaging 4-7 cm in males. Dental formula is 10/3, C0/1, P 3/3, M 3/3 (x2) = 32.
Habitat.
Evergreen forests and scrub, a habitat type now limited to fragmented forest patches along the southern
Cape
. The dominanttree species in areas inhabited by the
Cape
Blue Duiker in coastal
South Africa
is Trichocladus crinitus. Most foraging occurs in open forest glades, where vegetative ground coveris typically less than 10%. Denser cover is important for refuge, especially from aerial predators such as the crowned hawk-eagle (Stephanoaetus
coronatus
). Population densities are 14-28 ind/km?; this is significantly lower than the adjacent population of the
Zimbabwe
Blue Duiker in Kwa-Zulu-Natal, a discrepancy attributed to lower habitat quality (rather than to predation or competition).
Food and Feeding.
Folivorous, opportunistically frugivorous. Although most forest duikers rely on fruit, this is a highly variable and often limited food resource in
South Africa
. Fallen leaves and fruit are consumed from the ground. The
Cape
Blue Duiker is highly selective and appears to use scent in order to select the highest quality foods available. Stomach contents from a single individual indicate a strong preference for the leaves from Canthium obovatum; leaves from Canthium mundianum, Cassine papillosa, Apodytes dimidiata, Olea capensis macrocarpa, and Olinia ventosa were also present in small (but not trace) quantities. Fruit from C. mundianum, seed pods from Dietes iridioides, and traces of fungi were also identified.
Breeding.
There is no specific information available for this species from the wild. Reproduction in captivity in
South Africa
occurs year-round, with a distinct peak in births from September to November (over 50% of 49 recorded births). Other aspects of reproduction are likely similar to those of the
Zimbabwe
Blue Duiker.
Activity patterns.
Active throughout the day: transect counts show no significant difference in activity between morning, midday, and afternoon. No data are available on night-time activity.
Movements, Home range and Social organization.
Most field observations are of solitary individuals (73%), although pairs and groups of up to five individuals are sometimes seen. Sightings of groups are most frequent between October and February; these are most likely juveniles accompanying a parent. The
Cape
Blue Duiker uses regular pathways within forested habitats, including “game trails” created and used by larger species. The alarm call is a shrill whistle.
Status and Conservation.
CITES Appendix II. Classified as Least Concern on The [UCN Red List (combined with the other nine blue duiker species within the
P. monticola
complex). Habitat destruction has dramatically affected the
Cape
Blue Duiker, and the fragmented nature of the remaining forest pockets may lead to issues with long-term population viability. Viable populationsstill exist in several protected areas. Low populations have in the past been attributed to a rise in Caracal (Caracal caracal) numbers, although it now appears that habitat quality plays a significant role in determining population size.
Bibliography.
Crawford (1984), Grubb & Groves (2001), Hanekom (2001), Hanekom & Wilson (1991), IUCN/ SSC Antelope Specialist Group (2008as), Vernon (2001), Von Ketelhodt (1973).