As is common in other forest monkeys, predators are likely to include leopards, snakes, and birds of prey.
Known Predators:
Cercopithecus diana ranges from 40 to 55 cm in length, with a long tail 50 to 75 cm long. The coloration is extremely variable. These primates are generally black, with a white throat, ruff, pointed beard, and anterior side of arms. A white stripe runs down the thighs (Kingdon 1989). The posterior back and thighs are red-brown to orange (Grzimek 1990). Cercopithecus diana is catarrhine, with the nostrils close together and facing downward. The nail on each digit is flattened. The hallux and pollex are opposable. Prominant calluses, or ischial callosities, are present on the rump. The dental formula is 2/2, 1/1. 2/2, 3/3=32 (Vaughan 1986).
Range mass: 4 to 7 kg.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
These animals are thought to reach a maximum age of about 20 years.
Average lifespan
Status: wild: 20 years.
Typical lifespan
Status: wild: 20 (high) years.
Average lifespan
Status: captivity: 19.0 years.
Average lifespan
Sex: female
Status: captivity: 37.3 years.
Average lifespan
Sex: female
Status: captivity: 30.0 years.
Average lifespan
Status: captivity: 34.8 years.
Diana monkeys dwell in upper levels of primeval forest trees. They sleep in trees in closed forest canopies, and never make nests.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: forest ; rainforest
Cercopithecus diana is distributed from Sierra Leone to Ghana, in Western Africa.
Biogeographic Regions: ethiopian (Native )
The life span of C. diana may exceed two decades.
As in all primates, communication is likely to be varied and complex. Facial expression and body postures are some of the visual cues primates use to communicate mood and intent. Vocalizations are common in primates. Tactile communication is important in social bonding and maintenance of relationships. Grooming, mating, and caring for young are all very tactile.
Communication Channels: visual ; tactile ; acoustic
Perception Channels: visual ; tactile ; acoustic ; chemical
The current status of C. diana is CITES-Appendix I; US ESA- Endangered, IUCN- vulnerable (Wilson and Reeder 1993). Diana monkeys are seriously threatened by hunting and by destruction of forests (Grzimck 1990). One subspecies, C. diana roloway, is recognized; it lives in the Ivory Coast and Ghana.
US Federal List: endangered
CITES: appendix i
IUCN Red List of Threatened Species: vulnerable
Diana monkeys can carry and spread diseases like yellow fever and tuberculosis (Macdonald 1984).
Diana monkeys are used for food, pets, and in medical research (Macdonald 1984, Lawlor 1979).
As a prey species, these monkeys are likely to have an impact on predator populations. As fruit eaters, they are likely to help disperse seeds.
Ecosystem Impact: disperses seeds
Diana monkeys are omnivorous, eating fruits, flowers, young leaves, insects and invertebrates (Grzimck 1990, Macdonald 1984).
Animal Foods: insects; terrestrial non-insect arthropods
Plant Foods: leaves; fruit; flowers
Primary Diet: omnivore
Diana monkeys have a polygynous mating system. Courtship is short, since mates are usually familiar with each other. The female presents her rump prior to copulation in an appeasement gesture to signal readiness and vulnerability (Vaughan 1986).
Mating System: polygynous
Diana monkeys breed seasonally. They are polyestrus, with an approximately 31 day cycle. The gestation period lasts 5 months (Cockrum 1962). Females give birth to one or rarely two young at a time. The young are weaned at about six months and reach sexual maturity at about three years (Grzimek 1990).
Breeding interval: Because these animals breed seasonally, and given the long period of infant dependence, it is likely that females are only bale to produce once per year.
Breeding season: Copulations are probably times so that the young are born at the period of maximum food availability.
Range number of offspring: 1 to 2.
Average gestation period: 5 months.
Average weaning age: 6 months.
Average age at sexual or reproductive maturity (female): 3 years.
Average age at sexual or reproductive maturity (male): 3 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
Average birth mass: 475 g.
Average number of offspring: 1.
Average age at sexual or reproductive maturity (female)
Sex: female: 1962 days.
The young are relatively well developed at birth, with open eyes and the capability to grasp the mother and support their own weight (Macdonald 1984). Females nurse and care for their offspring for about six months. Daughters stay with their mothers as long as they live, whereas males leave the natal group near the time of adolescence (Macdonald 1984).
Parental Investment: precocial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Provisioning: Female, Protecting: Female); post-independence association with parents; extended period of juvenile learning; maternal position in the dominance hierarchy affects status of young
The Diana monkey (Cercopithecus diana) is an Old World monkey found in the high canopy forests in Sierra Leone, Liberia, and western Côte d’Ivoire.[6] Named for its white brow which is said to resemble the bow of the Roman goddess Diana, this black-grey guenon has a white throat, crescent-shaped browband, ruff and beard.
Two taxa formerly considered subspecies of the Diana monkey have recently been elevated to full species status: the roloway monkey (C. roloway) is found in Côte d'Ivoire and Ghana, and the Dryas monkey (C. dryas) found in the DR Congo.
This species can be found in West Africa, from Sierra Leone to Côte d'Ivoire.
The Diana monkey is found in the primary forests, and does not thrive in secondary forests. The species is regarded as endangered by the IUCN as well as by the United States Fish and Wildlife Service, the chief dangers to them being habitat destruction (they are now virtually confined to coastal areas) and hunting for bushmeat.
The Diana monkey ranges from 40 to 55 cm in length, excluding its tail, which is of a uniform 3–4 cm diameter and 50–75 cm long. Adults weigh between 4–7 kg.
They are generally black or dark grey, but have a white throat, crescent-shaped browband, ruff and beard; the browband gave the species its common name, since it was held to resemble the crescent on the brow of the goddess Diana. The monkeys' underarms are also white, and they have a white stripe down their thighs, while the backs of their thighs, and their lower backs, are a chestnut colour. Apart from the browband, ruff and beard, and some fringes on their limbs, their fur is rough and tough.
Individual, healthy Diana monkeys may live for up to 20 years. This species of monkey is active during the day, and feeds at all levels of the canopy, rarely venturing down to the ground for fear of predation. Diana monkeys retreat to the upper levels of the trees at night, though they do not make nests, preferring to sleep on branches. They feed mainly on fruit, blossoms and leaves, as well as occasional insects and invertebrates. The monkeys, in turn, are hunted and preyed upon by various animals, including the crowned hawk-eagle, the African leopard, the common chimpanzee, and humans.
The Diana monkey is a noisy presence in the forest. Its marked coloration allows a wide range of visual social signals. Female Diana monkeys produce specific alarm calls, alert calls and greeting/contact calls, depending on the occasion; in moments of predatory threat, they utilise distinct calls based on the specific predator in question, with some research suggesting that the vocabulary of the females’ vocalisations is larger and more variable than that of the males.[7]
Other forest residents, such as the yellow-casqued hornbill (in addition to other birds) and other primates, are able to discriminate between these and use them to take appropriate action, should a mutual threat be present in the immediate area. A similar system is observed in India with the axis deer (or chital) on the ground and the Hanuman langur in the trees above them; the two species are seemingly inseparable, living in near-symbiosis as the forest’s carnivore “warning-system”. The deer make shrill barks and calls if they spot a tiger, leopard, dhole, or wolf; the monkeys (likewise) scream and alert the deer of any potential threat and, in turn, their commotion alerts every animal within the area.[8]
Diana Monkeys communicate both to local group members and distant competitors with different kind of alarm sounds. Diana Monkeys produce loud noises to make other monkeys aware of leopards or other competitors in their area.
Groups consist of a single male with a number of reproducing females and their infants. In good conditions, adult females reproduce annually. Gestation lasts about 5 months, and the young nurse for a further 6 months. Normally, only a single infant is born. Although the young are born in a fairly well-developed condition, with open eyes and able to grasp their mothers, at least in zoo conditions, Diana monkey mothers appear anxious and possessive, rarely letting young infants leave them. As infants grow, however, they become very playful. Juveniles reach sexual maturity at an age of about 3 years. Daughters remain in their mothers' social groups, while males leave their natal groups shortly before attaining sexual maturity.
Like most primates, Diana monkeys can carry diseases that can be communicated to humans, like yellow fever and tuberculosis.[9] Native tribes in the tropical forest of West Africa poach Diana monkeys, which are sold as luxury meat and seen as a commodity.[10]
Diana monkey at the Henry Doorly Zoo.
Exemplar in Munich Zoo.
Cercopithecus diana in Singapore Zoo. Video clip
The Diana monkey (Cercopithecus diana) is an Old World monkey found in the high canopy forests in Sierra Leone, Liberia, and western Côte d’Ivoire. Named for its white brow which is said to resemble the bow of the Roman goddess Diana, this black-grey guenon has a white throat, crescent-shaped browband, ruff and beard.