 Cephalophus
callipygus
Peters's duiker |
Taxonomy | Description
| Reproduction | Ecology
| Behavior | Distribution
| Conservation | Remarks
| Literature |
| Taxonomy
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Cephalophus callipygus [Peters, 1876].
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Citation: Monatsb. K. Preuss. Akad. Wiss. Berlin, 1876:483.
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Type locality: Gabon, Gabon River.
The taxonomic record (above) is taken from Wilson and Reeder (1993). As
with most of the other red duikers, the taxonomic position of Cephalophus
callipygus is a matter of debate. This species may be associated
with C. natalensis, C. adersi, and C. weynsi, potentially
as a superspecies (Wilson, 1987). Some authors consider Peters's duiker
to be conspecific with C. natalensis (see Wilson, 1987), while C.
weynsi, C. harveyi, and C. adersi have been described
as subspecies of C. callipygus by others (Walther, 1990; East, 1999).
Peters's duiker is monotypic with no synonyms (Wilson, 1987; Wilson
and Reeder, 1993).
General Characteristics
Cephalophus callipygus is a relatively large duiker, with a body weight
averaging 20.1 kg (Dubost, 1984; Kingdon, 1997). Head and body length
is 80-115 cm, and shoulder height is between 45 and 60 cm (Walther, 1990;
Kingdon, 1997).
Reported measurements for Peters's duiker (Cephalophus
callipygus) |
| Source |
Adult Weight |
Head & Body Length |
Shoulder Height
|
Tail Length |
| Feer, 1989 |
~20-21 kg |
- |
- |
- |
| Happold, 1973 |
16-20 kg |
89 cm |
56 cm |
10 cm |
| Kingdon, 1997 |
16-23 kg |
80-115 cm |
45-60 cm |
8-16 cm |
Noss, 1998
from Banyanga, CAR |
16.46 kg (n=36) |
- |
- |
- |
| Walther, 1990 |
12-23 kg |
80-115 cm |
45-60 cm |
10-16 cm |
| Wilson, 1987 |
15-24 kg |
80-115 cm |
- |
10-16 cm |
The general coloration of Peters's duiker is a reddish brown, although there
is considerable variation between individuals - from pale and tawny to a
rich russet or even dark brown (Happold, 1973; Kingdon, 1997). The
general trend in coloration is for Central African populations of C.
callipygus to be darker than western forms (Wilson, 1987). A fine
black dorsal line begins between shoulders and runs along the spine to the
rump, where it widens considerably, expanding over the rear flanks and ending
on the underside of the tail (Happold, 1973). The noticeably darker
hindquarters are one of the defining characteristics of this species (Walther,
1990). This darker coloration also accents the legs, shoulders, neck,
and face of some individuals (Kingdon, 1997). The underparts are paler
than the rest of the body (Happold, 1973).
The head is not distinctly marked, with the exception of a rich russet or
orange brown forehead tuft of hair (Happold, 1973; Kingdon, 1997). Both
sexes have horns, which are short, pointed, and in line with the face (Walther,
1990). The horns grow 5.5-14 cm long, averaging 10 cm in length (Happold,
1973; Walther, 1990). The forehead of C. callipygus is the most
heavily reinforced of any duiker species, with the frontal bone in males
up to 13 mm thick (Kingdon, 1997).
Ontogeny and Reproduction
Peters's duiker breeds continually throughout the year, with some seasonal
rhythm (Feer, 1989; Dubost and Feer, 1992). Two peaks in birth rates
have been noted by Dubost and Feer (1992) - one in May/June and another in
December. These birthing peaks occur in the early months of the two
dry seasons, when the quantity and quality (protein content) of fruits
eaten by this species are at their highest (Dubost and Feer, 1992).
Dubost and Feer (1992) estimated the gestation period for C. callipygus
to be approximately 240 days, the same as the similarly-sized bay duiker
(C. dorsalis). Infants
weigh about 1 kg at birth, and are darker in color than adults (Walther,
1990).
Ecology and Behavior
C. callipygus inhabits moist equatorial forests, primarily found
in lowland forest, but also utilizing thickets (Wilson, 1987; Kingdon,
1997). Avoiding outlying riverine strips and gallery forests, Peters's
duiker prefers areas with dense undergrowth for shelter (Kingdon, 1997).
Because of this preference for low vegetation, this species does well
in forests which are regenerating after logging (Kingdon, 1997).
Peters's duiker is strictly diurnal (Feer, 1989; Kingdon, 1997). Unusual
for duikers, there is an active social system and polygynous social structure
(Feer, 1989). Adult females inhabit home ranges of approximately 40
hectares in size (Feer, 1989). Males are believed to be territorial
(Kingdon, 1997), although no estimate of their home range size has been made.
C. callipygus is known for dense populations which regenerate
rapidly (Feer, 1989). Density estimates from line transects in the
Central African Republic were 0.9 animals per km2, while net
encounters indicated population densities of 0.9-4.4 animals per
km2 (Noss, 1998). Other authors have reported densities
as low as 0.6 per km2 to as high as 15.5 per km2 (see Noss,
1998).
This species forages primarily in mature forest and is one of the most completely
frugivorous duiker species (Dubost, 1984; Kingdon, 1997). In two different
studies (Dubost, 1984; Feer, 1989), fruit was found to comprise between 82.7%
and 89.6% of the diet by dry weight based on examination of stomach contents.
Leaves are the next largest dietary component, comprising between 7.9-10.0%
of the diet, with petioles and stems following close behind at
6.2% (Dubost, 1984; Feer, 1989). Fruits and leaves were found
in the stomachs of all Peters's duikers sampled in both studies (Dubost,
1984; Feer, 1989). Flowers, fungi, and animal matter (principally insects)
are found much less frequently (in fewer than 50% of animals sampled), and
comprise less than 1% of the diet (Dubost, 1984).
The fruit consumption of C. callipygus is the lowest from March to
May, during the short rainy season, at which point leaves are eaten significantly
more than throughout the rest of the year (Feer, 1989). This species
is not specialized in respect to the species of fruits eaten, but is adapted
to feeding on a specific size of fruit: 40.2 % of fruits consumed are 1.0
to 2.0 cm in diameter, and 77.2% of fruits are between 0.5 cm and 3.0 cm
(Dubost, 1984). Dubost (1984) identified 55 fruit species in 20 stomachs
analysed, and Feer (1989) found an average of 8.5 species in each stomach
(n=51). The favored species of fruit, as determined by Dubost (1984),
are Xylopia hypolampra (Annonaceae), Cylindropsis parvifolia
(Apocynaceae), Canarium schweinfurthii (Burseraceae), Klaindedoxa
gabonensis (Irvingiaceae), Coelocaryon preussii or Pycnanthus
angolensis (Myristicaceae), and Staudtia stipitata (Myristicaceae).
Unweaned animals eat much less fruit than adults (52.7% of diet by dry weight),
and significantly more leaves (37.0%), but similar amounts of stems (9.8%)
and fungi (0.47) (Dubost, 1984).
Distribution
C. callipygus inhabits the central African rainforest block between
the Atlantic Ocean to the Congo and Ubangi Rivers (Wilson and Reeder, 1993).
Countries: Cameroon, Central African Republic, Congo, Equatorial Guinea,
Gabon (East, 1999)
Range Map (Compiled from IEA, 1998; East 1999)
Conservation Status
Peters's duiker is classified as a low risk, near-threatened species by the
IUCN (2003), but is not listed by CITES. The total population of this
species is estimated at 382,000 (East, 1999). The primary threats to
the survival of this species are habitat loss due to human settlement and
hunting (IUCN, 2003). Peters's duiker is especially affected by
snare hunting; in the Central African Republic this species accounted for
29% of all animal captured in snares (36 out of 105) - and 56% of captures
by weight (Noss, 1998). Indeed, hunters in the Central African Republic
equate their total returns in C. callipygus units (Noss, 1998).
Snare hunting does not appear to be sustainable for this species, even
under the most optimistic of circumstances, and unless mediatory actions
are taken, this species could decline drastically (Noss, 1998).
Remarks
The generic name Cephalophus is derived from kephale (Greek),
the head, and lophus (Greek), a crest, referring to the prominent
tuft of hair on the forehead of this, and most other, duiker species. The
specific name callipygus is likely from kalos (Greek) meaning
beautiful or fair and puge (Greek) the rump - the dark color of the
rump is the defining characteristic of this species (although whether it
is "beautiful" is up for debate!).
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French
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Céphalophe de Peter (Happold, 1973)
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Céphalophe de Peters (Walther, 1990; Kingdon, 1997)
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German
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Schönsteiss-Rotducker (Happold, 1973)
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Petersducker (Kingdon, 1997)
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Literature
Cited
Dubost, G. 1984. Comparison of the diets of frugivorous forest
mammals of Gabon. Journal of Mammalogy; 65(2): 298-316.
Dubost G., and F. Feer. 1992. Saisons de reproduction des petits
Ruminants dans le nord-est du Ghabon, en fonction des variations des ressources
alimentaires. Mammalia; 56(1): 25-43.
East, R. [compiler]. 1999. African Antelope Database 1998. IUCN/SSC Antelope
Specialist Group. Gland, Switzerland and Cambridge, UK: IUCN.
Feer, F. 1989. Comparaison des régimes alimentaires de
Cephalophus callipygus et C. dorsalis, Bovidés sympatriques
de la forêt sempervirente africaine. [Comparative diet of
Cephalophus callipygus and C. dorsalis, sympatric bovids of
the African sempervirent forest]. Mammalia; 53(4): 563-620.
Happold, D. C. D. 1973. Large Mammals of West Africa. London:
Longman Group, Ltd.
IEA (Institute of Applied Ecology) 1998. Cephalophus callipygus.
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://www.gisbau.uniroma1.it/amd/amd020b.html
IUCN (International Union for Conservation of Nature and Natural Resources).
2003. 2003 IUCN Red List of Threatened Species. Available
online at http://www.redlist.org/
Kingdon, J. 1997. The Kingdon Field Guide to African Mammals. Academic
Press, London and New York: NaturalWorld.
Noss, A. J. 1998. The impacts of cable snare hunting on wildlife
populations in the forests of the Central African Republic. Conservation
Biology; 12(2): 390-398.
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, V. J. [compiler] 1987. Action plan for duiker conservation -
IUCN/SSC Antelope Specialist Group and Chipangali Wildlife Trust.
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/
Additional Resources
Feer, F. 1989. The use of space by two sympatric duikers
(Cephalophus callipygus and Cephalophus dorsalis) in an African
rainforest - the role of activity rhythms. Revue d'Ecologie la Terre
et la Vie; 44(3): 225-248.
Feer, F. 1995. Seed dispersal in African forest ruminants.
Journal of Tropical Ecology; 11(4):
683-689..
Feiler A. 1990. Distribution of mammals in Angola and notes on
biogeography. In Vertebrates in the Tropics. Edited by G. Peters
and R. Hutter. Museum Alexander Koenig, Bonn. pp. 221-236.
Gautier-Hion, A., L. H. Emmons, and G.Dubost. 1980. A
comparison of the diets of three major groups of primary consumers of Gabon
(primates, squirrels and ruminants). Oecologia (Berlin); 45: 182-189.
Haltenorth, T., and H. Diller. 1980. A Field Guide to the Mammals
of Africa, including Madagascar. London: Collins.
Heymans, J., and J. Lejoly. 1981. Sur la répartition des
Cephalophinae en foret ombrophile. Revue de Zoologie Africaine; 95:
1-10.
Muchaal, P. K., and G. Ngandjui. 1999. Impact of village hunting
on wildlife populations in the western Dja Reserve, Cameroon. Conservation
Biology; 13(2): 385-396.
Noss, A. J. 1999. Censusing rainforest game species with communal
net hunts. African Journal of Ecology; 37(1): 1-11.
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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