L'Hoest Monkey
Cercopithecus lhoestiSclater, 1899
Photo by Tim Knight
Photo by Tim Knight
Identification
The L'hoest monkey, also know as the mountain monkey, is a very dark, richly colored animal with a pure white chin ruff framing the face. The body is black with a grizzled mahogany back, the lips and nose are black on a pale grey face. The broad nose has a black heart-shaped "spot" of dense hair on it, which is visually obliterated by being incorporated within a black facial triangle. The males are larger that the females and have bright mauve testes (Kingdon, 1974).Geographic Range
Most of the East African populations occur in the montane areas of western Uganda, but the species is also found in Kibale, Kalinzu and Kayonza which are medium altitude forests. In these areas the species prefers the thick regenerating growth in felled compartments. The bamboo forest zone seems to define the upper altitudinal limits of the range (Kingdon, 1974).
Natural History
Photo by Tim Knight
Ground feeding is common and the species will venture a long way across open country, wooded savanna, heathland and cultivated fields. They eat the fruit of Podocarpus, Pygeum, Hagenia, Polyscias fulva, Myrianthus arboreus, Maesa lanceolata and other montane trees, also the leaves of various trees, shrubs and herbs. In the undergrowth they eat the fruit of Rubus, Aframomum, Eugenia and Cucurbitaceae; the sporangium of Pteridium aquilinum, bracken shoots and mushrooms are common foods. Albizzia resin is relished, insects and lichen are also eaten. Bananas, peas and cassava attract the mountain monkey to the fields and they have acquired a taste for the fruit of the Australian black wattle (Kingdon, 1974).
Group size ranges are generally not large and it was reckoned by Moller that 17 individuals constitute an average group. He found that solitary males were not infrequently met with in the vicinity of larger groups.In the Kayonza Forest, Moller found that one, or more rarely two adult males were found in a troop (Kingdon, 1974). Butynski found that group size in L'hoest monkeys averages around 17 individuals (N=25) in Kibale, Uganda.
The details of the reproduction and sexual life of this species are imperfectly known. There is some evidence that a limited birth peak may occur in February (Kingdon, 1974). Butynski reports a birth peak between December and February in Kibale, Uganda (Cords, 1986). No gestation length was reported, but other Cercopithecus spp. have a gestation period ranging from 140 to 187 days.
Predators might include the leopard and golden cat, as these carnivores are common in their habitat. The handsome skin of the mountain monkey is sought after as a shoulder bag by the Bakonjo and the Bakiga, and the former organize elaborate hunts with packs of dogs. The difficult terrain does not make these hunts an easy matter and the species is certainly not threatened by this practice, but it does perhaps explain why the animal is generally very wary (Kingdon, 1974).
Conservation Status
CITES - Appendix II; U.S. ESA - Endangered; IUCN - Vulnerable.
References:
Kingdon, J. 1974. East African Mammals Vol. 1, The University of Chicago Press, Chicago.Cords, M. 1986. Forest guenons and patas monkeys: male-male competition in one-male groups. Pp. 98-111 in: Smuts, B. B.; Cheney, D. L.; Seyfarth, R. M.; Wrangham, R. W.; Struhsaker, T . T. (eds.), Primate Societies. The University of Chicago Press, Chicago.
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