Blue monkeys are a social species. An interesting aspect of the interspecific relations of blue monkeys is their involvement in mixed groupings consisting of two or more primate species (Rudran, 1978). Blue monkey associations with redtails and red colobus sometimes last for six to seven hours within a day (Rudran, 1978). Often, blue monkeys will associate with other species to form coalitions against other groups, to help find food, and also for added protection against predators. With polyspecific associations groups are able to cover a larger area when foraging for food. They are also able to get a broader view of a large area and warn of an approaching predator by alarm calls.
As in other species of primates, communication in these monkeys is likely to be complex and varied. Because of their facial markings, facial expressions are extremely marked. Body postures add to the visual signals used in communication. Vocalizations are common in primates and are probably used by diademed monkeys. Tactile communication occurs between mates and rivals, as well as between mothers and their offspring. Grooming is an important physical activity which helps to solidify social bonds.
Communication Channels: visual ; tactile ; acoustic
Perception Channels: visual ; tactile ; acoustic ; chemical
Survival threats to blue monkeys include habitat destruction, such as the clearing of rain forests. Blue monkeys are also destroyed for eating cultivated crops or destroying exotic trees (Fleagle, 1988).
US Federal List: threatened
CITES: appendix ii
IUCN Red List of Threatened Species: least concern
Blue monkeys eat cultivated crops and destroy exotic trees.
Negative Impacts: crop pest
In Uganda, blue monkeys are hunted for their meat (Fleagle, 1988).
Positive Impacts: food
As a prey species, these monkeys probably have some impact on predator populations. In addition, they are likely to be important in seed dispersal because of their frugivory.
Blue monkeys are frugivorous and folivorous in nature, eating mainly fruits and leaves. In addition, blue monkeys tend to concentrate their invetebrate feeding on slow-moving slugs and worms (Rudran, 1978).
Animal Foods: mollusks; terrestrial worms
Plant Foods: leaves; fruit
Primary Diet: herbivore (Folivore , Frugivore )
Cercopithecus mitis is found in rain forests of central, eastern, and southern Africa. The species can also be found in the Congo basin.
Biogeographic Regions: ethiopian (Native )
Cercopithecus mitis is found in a variety of habitats. They are very dependent upon humid, shaded areas with abundant water and tall trees which provide both food and shelter.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: forest ; rainforest ; scrub forest
Longevity for this species has not been reported, but if C. mitis is like other members of the genus Cercopithecus, the maximum lifespan is probably around 20 years.
Average lifespan
Sex: female
Status: captivity: 25.0 years.
Average lifespan
Sex: female
Status: captivity: 27.1 years.
Blue monkeys are small (ranging in weight from 4 to 6 kg) and arboreal. The face is nearly naked, usually dark in color (infrequently blue), and has well-developed musculature (Lawlor, 1979). Cercopithecus mitis is also known as the diademed monkey because it has a prominent row of forward pointing white fur just above its brow line (Rudran, 1978).
White whiskers are well developed in males. Males are larger than females. Male canines are also slightly larger than the female canines (Rudran,1978).
These monkeys are catarrhine; the nostrils are close together and they face downward. They have cheek pouches to carry food while foraging (Rudran, 1978).
The dental formula of C. mitis is 2/2 1/1 3/3 2/2=32.
The nail on each digit is flattened, and the pollex is opposable (Lawlor, 1979).
The upper parts of the body are gray and the limbs are darker in appearance. Some young have indistinct russet-colored rump patches, which has not been seen in adults (Dorst and Dandelot, 1970).
Range mass: 4 to 6 kg.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger
Average basal metabolic rate: 19.276 W.
As is true for other forest dwelling monkeys, C. mitis likely falls prey to leopards. Other potential predators include snakes and birds of prey.
Known Predators:
Blue monkeys have a polygynous mating system, although promiscuous mating has been known to occur (Estes, 1991). Females solicit copulation from the males using body language (Estes, 1991). Females present their hindquarters to a male to indicate that they are ready to copulate. During copulation, females pout, looking over their shoulder at the male.
Mating System: polygynous ; polygynandrous (promiscuous)
Breeding occurs throughout the year. The gestation period lasts 5 months (Rudran, 1978). The female gives birth to a single offspring. The young are weaned at about six months and reach sexual maturity at about three years (Grzimck, 1990).
Breeding interval: Females are capable of producing young annually if food is available.
Breeding season: Breeding occurs throughout the year.
Average number of offspring: 1.
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 ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
Average birth mass: 366.4 g.
Average gestation period: 132 days.
Average number of offspring: 1.
Average age at sexual or reproductive maturity (male)
Sex: male: 1673 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 1673 days.
The young are relatively well developed at birth, with open eyes and the capability to grasp their mother and support their own weight (Macdonald, 1984). Females provide their young with milk for about six months. Allomaternal care does occur amongst the female troup members (Bourliere and Bertrand, 1970).
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); extended period of juvenile learning
