 Cephalophus
rufilatus
Red-flanked duiker |
Taxonomy | Description
| Reproduction | Ecology
| Behavior | Distribution
| Conservation | Remarks
| Literature |
| Taxonomy
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Cephalophus rufilatus [Gray, 1846].
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Citation: Ann. Mag. Nat. Hist., [ser. 1], 18:166
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Type locality: Sierra Leone, Waterloo Village.
The taxonomic record (above) is taken from Wilson and Reeder (1993).
C. rufilatus is included in the subgenus Cephalophorus
[Gray, 1842] (Nowak, 1991). This duiker was placed by Heyden
(1963) into a superspecies with C. nigrifrons due to similarities
in skull structure, but the two are generally considered to be distinct species
on the basis of coloration and sympatry in ranges (Wilson, 1987; Kingdon,
1982). Two subspecies of the red-flanked duiker are currently recognized;
C. r. rufilatus (Senegal to the Chari and Benue valleys) and C.
r. rubidior (Chari to Nile valleys) (Kingdon, 1997). Invalid synonyms
for Cephalophus rufilatus include C. rubidior and C.
cuvieri (Wilson and Reeder, 1993).
General Characteristics
Adult weights have been reported from 6-14 kg (Kingdon, 1997), but the majority
of sources list the weight towards the upper end of this range, giving an
average of 11.4 kg. Head and body length measurements average 70 cm.
Shoulder height values encompass the range of 30-40 cm (Walther, 1990),
and average just over 35 cm.
Reported measurements for red-flanked duiker (Cephalophus
rufilatus) |
| Source |
Adult Weight |
Head & Body Length |
Shoulder Height
|
Tail Length |
| Happold, 1987 |
11 - 13.5 kg |
66 cm |
36 cm |
10 cm |
| Kingdon, 1982 |
12-14 kg |
75-80 cm |
35-38 cm |
8-9 cm |
| Kingdon, 1997 |
6-14 kg |
60-80 cm |
30-38 cm |
7-10 cm |
| Walther, 1990 |
9-12 kg |
60-70 cm |
30-40 cm |
7-10 cm |
| Wilson, 1987 |
9-12 kg |
60-70 cm |
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7-10 cm |
The coat is generally an orange-rufous, with no marked difference in coloration
on the ventral surface (Happold, 1987). A broad bluish-gray strip is
located along the mid-dorsal line, which gradually merges with the rufous
pelage on the upper flanks (Happold, 1987). This dorsal band is darker
in the eastern subspecies (C. r. rubidior) than in the western race
(C. r. rufilatus) (Kingdon, 1982). The lower legs are dark blue-gray
in color, giving C. rufilatus the impression of wearing
stockings (Kingdon, 1982). The narrow tail is 7-10 cm long and ends
with a black tuft (Happold, 1987).
The profile of the nose is straight, and the skull is narrow (Kingdon, 1982).
A blue-black stripe runs down front of face, ending at the black
muzzle (Happold, 1987). The dark nose and black lower lip contrast
sharply with the white upper lip and underside of the jaw (Kingdon, 1982).
Large dark slits on the cheek ventral and rostral to each eye mark
the locations of the preorbital (or suborbital) glands (Happold, 1987).
The ears are wide and relatively large, approximately 7 cm long
(Kingdon, 1982). The back sides of the ears are dark brown to black,
while the inner borders have white 'flashes' (Happold, 1973; Happold, 1987;
Kindgon, 1982). There is a prominent vertical tuft of dark hair
on the forehead [see remarks at bottom] (Happold, 1987; Kingdon, 1982).
On either side of the forehead tuft grow the horns, which may be found in
both sexes, but, while always being present in males, are regularly lacking
in females (Happold, 1987; Wilson, 1987). Additionally, the forehead
tuft may hide the horns from view (Walther, 1990). The horns are
simple spikes, being smooth and pointed in the same plane as the forehead
(Happold, 1987). Reported horn lengths vary, but representative values
of 6-9.5 cm for males and 3-4 cm for females are given by Walther (1990).
Ontogeny and Reproduction
Young animals have been reported in the dry season or early wet season (Happold,
1987). Gestation times may vary from 223-245 days, with two of three
reported values being above 240 days (Dittrich, 1970, 1972; in Schweers,
1984). After birth, the single young is concealed by its mother in
dense vegetation, where it stays still, even if approached closely (Happold,
1987). Recorded birth weights vary from 760 g - 1,335 g, with an average
of just over 1,000 grams (n=5, with two measurements being taken the second
day after birth) (Dittrich, 1969; Dittrich 1979). Fecundity is likely
high due to the observed maintenance of population numbers despite heavy
hunting (Happold, 1987). A captive individual at the Los Angeles Zoo
is currently (January 2003) over 15 years old (ISIS, 2003).
Ecology
Cephalophus rufilatus inhabits riverrine/ riparian forests and savanna
areas near vegetative cover (Agbelusi, 1992). Although discussed by
some authors as a forest-edge species, usable habitat requires only dense
vegetation growth, and as a result the red-flanked duiker may be found far
from true forest along drainage lines (Kingdon, 1982). The red-flanked
duiker rarely leave areas with cover (Happold, 1987).
C. rufilatus lives singly or in pairs, and is very sedentary (Happold,
1987; Henshaw & Ayeni, 1971). Animals occupy small home ranges,
which may be maintained for many months provided there is no disturbance
(Happold, 1987). Although these home ranges do not usually overlap
between individuals, it is not agreed whether they constitute true territories,
although Agbelusi (1992) states that C. rufilatus is highly
territorial (Happold, 1987). These home ranges are marked with
secretions from the preorbital gland, which is relatively large compared
to other red duiker (Happold, 1987; Kingdon, 1982). Active marking
behavior in itself does not imply territoriality, as stated by Kingdon (1982).
The red-flanked duiker is primarily a browser, feeding on mostly on leaves
(60% of diet) but also on twigs, flowers, and fruits (Agbelusi, 1992).
Preferred plant food species include Piliostigma thonningii
(leaf tips), Combretum sp. (twigs and leaves), Mucuna flagellipes
(twigs and leaves, especially in March), and Spondias mombin (fruit)
(Agbelusi, 1992). Leaves of Pterocarpus erinaceous, Bridelia
micrantha, Vitex domiana, Annoa senegalensis, and
Phyllanthus muellerianus are also taken, as are fruits of Cola
milleni, Fiscus capensis, Blighia sapida, and Gmellina
aborea (Agbelusi, 1992). C. rufilatus does not appear to
eat roots, bark of trees, or grasses, and seldom visits mineral licks (Agbelusi,
1992; Happold, 1987; Henshaw & Ayeni, 1971). When feeding, the
red-flanked duiker moves slowly from plant to plant nibbling small leaves,
then moves a meter or so and begins browsing again (Happold, 1987).
Behavior
Reports regarding the primary time of activity vary from primarily diurnal
(Agbelusi, 1992), through crepuscular to nocturnal, with some activity occuring
in the early mornings and late afternoon (Happold, 1987). The
red-flanked duiker is shy and wary, when disturbed rushing with a bouncing
gait to nearest cover, keeping the head low [see remarks at bottom]
(Happold, 1987). The alarm call is a shrill bark (Happold, 1987)
Distribution
Gallery forests in western and central Africa. Dowsett (1993) argues
that C. rufilatus is likely restricted to savanna-forest transition
zones north of the equator, suggesting that reports of this species
in Congo and Gabon are likely due to the mentioning of red-flanked duiker
in the countries' legislation, rather than due to evidence or reputable sightings
(Dowsett, 1993).
Countries: Benin, Burkina Faso, Cameroon, Central African Republic,
Chad, Côte d'Ivoire, Gambia, Ghana, Guinea [?], Guinea-Bissau,
Mali, Niger, Nigeria, Senegal, Sierra Leone, Sudan, Togo, Uganda [Regionally
extinct?] (IUCN, 2002).
Range Map (Compiled from IEA, 1998; Kingdon, 1997; Walther, 1990)
Conservation Status
The red-flanked duiker is classified as a lower risk, conservation dependent
species by the IUCN (IUCN, 2002), and is not listed by CITES. C.
rufilatus appears to be more resilient to habitat loss than other duiker
species (Kingdon, 1982; Eves & Bakarr, 2001). Nevertheless, this
species is threatened outside of well-managed areas due to encroachment of
agricultural lands and increased hunting pressure (Eves & Bakarr, 2001;
IUCN, 2002). The total population is estimated at 170,000 individuals
(East, 1999).
Remarks
The genus Cephalophus is derived from kephale (Greek), the
head, and lophus (Greek), a crest, referring to the prominent tuft
of hair on the forehead of most duiker species. The red-flanked duiker's
specific name rufilatus translates literally to "red-flank"
(rufus (Latin) red; latus (Latin) side, flank).
The common name duiker ("DIKE-er") is Afrikaans for "diver" or "diving buck",
a reference to the species' characteristic flight into the undergrowth when
alarmed (Wilson, 1987).
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Local names (from Happold, 1973; Happold 1987; Kingdon, 1982)
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Tili [Madi]
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Gadan-Kurmi, Makurna [Hausa]
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Esuru, Esuro [Yoruba]
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Jabare [Fulani]
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Akogyei, Asebee [Twi]
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Konani [Dyula]
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French
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Céphalophe à flancs roux (Kingdon, 1997)
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German
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Rotflankenducker, Blaurückenducker (Kingdon, 1997; Walther,
1990).
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Spanish
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Duiker de flancos rojos
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Literature
Cited
Agbelusi, E. E. 1992. Habitat preference and food habits of red-flanked
duiker in Ifon Game Reserve: Ondo State, Nigeria. Ongules/Ungulates
91: 229-232
Dittrich, L. 1969. Birth weights and weight increases of African
antelopes born at Hanover Zoo. International Zoo Yearbook 9:
118-120
Dittrich, L. 1979. Some further birth weights of African
antelopes born at Hanover Zoo. International Zoo Yearbook 19:
201
Dowsett R. J. 1993. The red-flanked duiker Cephalophus rufilatus does
not occur in Congo and Gabon. Mammalia 57(3), 445-446.
East, R. [compiler]. 1999. African Antelope Database 1998. IUCN/SSC Antelope
Specialist Group. Gland, Switzerland and Cambridge, UK: IUCN.
Eves, H. E. and M. I. Bakarr 2001. Impacts of bushmeat hunting
on wildlife populations in West Africa's Upper Guinea forest ecosystem.
In Hunting and Bushmeat Utilization in the African Rain Forest.
Washington D.C.: Conservation International.
Happold, D. C. D. 1973. Large Mammals of West Africa. London:
Longman Group, Ltd.
Happold, D. C. D. 1987. The Mammals of Nigeria. Oxford: Clarendon Press.
Henshaw J. and J. Ayeni 1971. Some aspects of big-game utilization
of mineral licks in Yankari Game reserve, Nigeria. East African
Wildlife Journal 9: 73-82
IEA (Institute of Applied Ecology) 1998. Cephalophus rufilatus.
In African Mammals Databank - A Databank for the Conservation
and Management of the African Mammals Vol 1 and 2. Bruxelles: European
Commission Directorate. Available online at
http://gorilla.bio.uniroma1.it/amd/amd056b.html
ISIS (International Species Information System). 2003 Specimen
Records.
IUCN (International Union for Conservation of Nature and Natural Resources).
2002. 2002 IUCN Red List of Threatened Species. Available
online at http://www.redlist.org/
Kingdon, J. 1982. East African Mammals: An atlas of evolution in Africa.
London: Academic Press.
Kingdon, J. 1997. The Kingdon Field Guide to African Mammals. Academic
Press, London and New York: NaturalWorld.
Nowak, R. M. [editor]. 1991. Walker's Mammals of the World (Fifth Edition).
Baltimore: The Johns Hopkins University Press.
Schweers, V. S. 1984. Zur Fortpflanzungsbiologie des Zebraduckers
Cephalophus zebra (Gray, 1838) im Vergleich zu anderen
Cephalophus-Arten [On the reproductive biology of the Banded duiker
Cephalophus zebra (Gray, 1838) in comparison with other species of
duiker]. Zeitschrift fur Saugetierekunde 49: 21-36
Walther, F. R. 1990. Duikers and Dwarf Antelopes.
In Grzimek's Encyclopedia of Mammals, Volume 5. Edited
by S. P. Parker. New York: McGraw-Hill. pp. 325-343.
Wilson, D. E., and D. M. Reeder [editors]. 1993. Mammal Species of the World
(Second Edition). Washington: Smithsonian Institution Press.
Available online at
http://nmnhwww.si.edu/msw/
Wilson, V. J. [compiler] 1987. Action plan for duiker conservation -
IUCN/SSC Antelope Specialist Group and Chipangali Wildlife Trust.
Additional Resources
Dipeolu, O. O., and O. A. Akinboade. 1984. Studies on ticks of
veterinary importance in Nigeria. XI. Observations on the biology of ticks
detached from the red-flanked duiker (Cephamophys rufulatus) and parasites
encountered in their blood. Veterinary Parasitology 14(2): 87-93.
Dittrich, L. 1970. Beitrag zur Fortpflanzungsbiologie afrikanischer
Antilopen im Zoologischen Garten. Zool. Garten N. F.; 39: 16-40.
Dittrich, L. 1972. Beobachtungen bei der Haltung von
Cephalophus-Arten sowie zue Fortpflanzung und Jugendentwicklung von
C. dorsalis und C. rufilatus in Gefangenschaft. Zool.
Garten N. F.; 42: 1-6.
Dittrich, L. 1972. Gestation periods and age of sexual maturity
of some African antelopes. International Zoo Yearbook; 12: 184-187.
Dubost, G., and F. Feer. 1988. Variabiulite comportmentale a
l'interieur du genre Cephalophus (Ruminantia, Bovidae), par l'exemple
de C. rufilatus Gray, 1846 [Behavioral differences in the genus
Cephalophus (Ruminantia, Bovidae), as illustrated by C. rufilatus
Gray, 1846]. Zeitschrift fur Saugetierekunde. 53(1):31-47.
Eves, H. 2000. Duikers: A primary target for Africa's bushmeat trade.
Animal Keepers' Forum 27(11):497-505.
Esser, J. D. 1980. Grouping pattern of ungulates in Benoue National
Park and adjacent areas, Northern Cameroon. Spixiana 3(2): 179-192.
Fischer, F., and K. E. Linsenmair. 2001. Decreases in ungulate
population densities. Examples from the Comoe National Park, Ivory Coast.
Biological Conservation 101(2): 131-135.
Hofmann, T., and H. Roth. 2003. Feeding preferences of duiker
(Cephalophus maxwelli, C. rufilatus, and C. niger) in
Ivory Coast and Ghana. Mammalian Biology 68(2): 65-77
Meteyer, C. U., B. J. Gonzales, W. P. Heuschele, and E. B.Howard. 1989.
Epidemiologic and pathologic aspects of an epizootic of malignant catarrhal
fever in exotic hoofstock. Journal of Wildlife Diseases 25(2): 280-286.
Steinhauer, B. B. 1987. Count and distribution of large mammals
of Comoe National Park (Ivory Coast): Notes on the size of the troops and
their reproductive seasons. Mammalia 51(2): 283-304.
*Thomas, O. 1892. On the antelopes of the genus Cephalophus.
Proceedings of the Zoological Society of London; 1892: 413-430.
van Vuuren, B. J., and T. J. Robinson. 2001. Retrieval of four
adaptive lineages in duiker antelope: Evidence from mitochondrial DNA sequences
and fluorescence in situ hybridization. Molecular Phylogenetics and
Evolution 20(3): 409-425.
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