This species ranges from northern Angola north to the Congo-Oubangui river system, and then eastwards (with a disjunct range) to the montane and coastal forests of Tanzania and Kenya. Recorded to 2,415 m asl in Kenya (Anderson et al. 2007).

There are six described subspecies.

C. a. angolensis ranges from Angola north to the great bend of the Congo River.

C. a. cottoni occurs from north-east of the River Congo, east to Lake Albert and north to the Uele-Oubangui river system (this subspecies forms a hybrid zone with C. a. ruwenzorii in the south of its range).

The subspecies C. a. ruwenzorii ranges along both sides of the western Rift, from the Semiliki Valley and the Rwenzori Mountains through south-eastern Uganda, Rwanda, Mount Kahuzi (Democratic Republic of the Congo) and Burundi to the eastern shores of Lake Tanganyika in Tanzania.

C. a. cordieri is present in the Democratic Republic of the Congo where it occurs between the Lowa and Luama rivers from the Lualaba River in the west to close to Lake Kivu in the east, where it forms a hybrid zone with C. a. ruwenzorii.

The subspecies C. a. prigoginei is endemic to Mount Kabobo, in the eastern Democratic Republic of the Congo.

The eastern subspecies, C. a. palliatus, is discontinously distributed in the Southern Highlands and coastal and gallery forests of southern and eastern Tanzania and south-eastern Kenya. Kenyan distribution of C. a. palliatus is solely restricted to the southern coastal forests of the Kwale District (Anderson et al. 2007).

An isolated, undescribed subspecies is present on Mount Nkungwe and adjacent uplands in the Mahale Mountains of western Tanzania.

Angolan colobus monkeys are found from eastern Nigeria through Cameroon, eastern Gabon, northern Congo, the central African Republic, northeastern Zaire, Uganda, Ruanda, Ethiopia, Kenya, and northern Tanzania (Grzimek, 1990).

Biogeographic Regions: ethiopian (Native )

Colobus monkeys are medium-sized, arboreal monkeys with slender bodies and long tails. The five recognized species of Colobus share the following characteristics: a reduced thumb, prominent rump callosities, and a complex stomach which aids in the digestion of cellulose. Angolan colobus monkeys have long, silky hair. They are black with a white brow band, cheeks, and throat. They have long-haired white epaulettes on the shoulders and the lower half of the tail is white. The tail length is 706 mm for females and 829 mm for males and head and body length ranges from 490 to 680 mm. Mass varies between 6 and 11.4 kg, with males slightly larger than females. Young are born completely white and begin changing to their adult pelage at about three months of age (Rowe, 1996; Grzimek, 1990; Wisconsin Primate Research Center, 2000).

Range mass: 6.1 to 11.7 kg.

Average mass: 8.90 kg.

Range length: 49 to 68 cm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: male larger

Habitat and Ecology

Systems

• Terrestrial

Angolan colobus monkeys are found in various habitat types such as gallery, montane, lowland, and bamboo forests. They are also found in savannas and swamp lands. This species inhabits primary and secondary lowland to montane forest up to 3000m (Rowe, 1996; Grzimek, 1990).

Range elevation: 3000 (high) m.

Habitat Regions: tropical ; terrestrial

Terrestrial Biomes: forest ; rainforest ; scrub forest

Wetlands: swamp

Angolan colobus monkeys are primarily folivorivous, although they also feed on stems, bark, flowers, buds, shoots, fruits, some aquatic plants' fruits and insects. They are also known to eat clay from termite mounds. In many parts of their range, young leaves of the hackberry tree are the food of choice. They can eat up to two to three kilograms of leaves a day and normally feed in the morning and evening (Rowe 1996, Estes 1991).

Animal Foods: insects

Plant Foods: leaves; wood, bark, or stems; fruit; flowers

Primary Diet: herbivore (Folivore )

This species provides food for some large predators, such as eagles and large cats. They may disperse seeds of the fruits they eat.

Angolan colobus monkeys are diurnal and highly arboreal, which may help avoid predators that feed at night. They are also able to avoid predators by maneuvering quickly through the trees and by group members joining together to defend themselves (Sanders 2000, Grzimek 1990).

Known Predators:

• eagles (Accipitridae)
• leopards (Panthera pardus)
• humans (Homo sapiens)

Colobus angolensis is prey of:
Accipitridae
Homo sapiens
Panthera pardus

This list may not be complete but is based on published studies.

Colobus angolensis preys on:
Insecta

This list may not be complete but is based on published studies.

Angolan colobus monkeys can live for 20 years in the wild and up to 30 years in captivity (Grzimek 1990).

Range lifespan

Status: wild: 20 (high) years.

Range lifespan

Status: captivity: 30 (high) years.

Maximum longevity: 35.3 years (captivity) Observations: One wild born specimen was still alive after nearly 35 years in captivity, making it around 35.3 years old (Richard Weigl 2005).

Colobus angolensis is polygynous. Dominant adult males control reproductive access to the females within their family group. Younger males from within the group or from other groups may periodically replace the dominant male. Females of the family group mate with the dominant male.

Mating System: polygynous

In most Angolan colobus social groups there is one adult male present with about 2 to 6 females. Larger groups generally have more than one resident male. A behavior called presenting is performed by the female to communicate to the male that she is ready for copulation (Estes, 1991; Nowak, 1999). The gestation period ranges from 147 to 178 days and a single offspring is generally born, though twins are possible. In this species, the infants are born all white and start changing color at about 3 months old. Young are not weaned until they are about 15 months of age. Males reach sexual maturity in four years, females in about two years (Grzimek, 1990).

Breeding interval: It is likely that females are capable of producing offspring ever two years.

Breeding season: There is no distinct breeding season.

Range number of offspring: 1 to 2.

Average number of offspring: 1.00.

Range gestation period: 147 to 178 days.

Average weaning age: 15 months.

Range age at sexual or reproductive maturity (female): 2 to 4 years.

Range age at sexual or reproductive maturity (male): 2 to 4 years.

Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous

Average number of offspring: 1.

Young Colobus monkeys are cared for by their mothers and by other members of the social group. The infants are weaned in about 15 months.

Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Male, Female); pre-independence (Provisioning: Female, Protecting: Male, Female); extended period of juvenile learning

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Species: 4
Species With Barcodes: 1

Angolan colobus monkeys are not considered endangered and may be fairly abundant in parts of their range. However, they are vulnerable to habitat destruction and have suffered extensively by hunting for bushmeat and skins, especially in highly populated areas. Populations are declining fairly rapidly in some areas such as the Kakamega forest in Kenya (Von Hippel 2000, Grzimek 1988).

CITES: appendix ii

IUCN Red List of Threatened Species: least concern

Population

Population Trend

Major Threats

Conservation Actions

Although all primate species may harbor diseases that can be passed to humans, Angolan colobus monkeys do not have significant negative impacts on humans.

Angolan colobus monkeys benefit the people of Africa by providing them with meat and skins. They also attract ecotourism activities and have been used in research (Von Hippel 2000).

Positive Impacts: food ; ecotourism ; research and education