The Angolan black and white colobus monkey has black hair with a white brow band, cheeks, and throat. Long haired white epaulettes stream from the shoulders.
The lower part of the tail is white as is the band on the buttocks. This subspecies, palliatus, is only found in the south eastern Kenya and Tanzania coastal forests and the Tanzanian eastern arc mountains of the East and West Usambaras, South Pares, Nguru, Nguu and Uluguru Mountains. Although the palliatus were previously found along the entire coast, deforestation and hunting in the northern parts have resulted in their restriction to isolated pockets of forests south of Mombasa. Travelling further inland, the Guereza black and white colobus occur. These are much bigger, have longer coats, have a full cape of white hair around their backs and full bushy white tail.
Here in Diani there are approximately 450 colobus monkeys identified from the annual census, carried out every October - the second highest known concentration of this subspecies in Kenya. Overall, there are an estimated 2000 remaining in Kenya. The Angolan Colobus is believed to be at risk from habitat loss and hunting. Its highly fragmented range suggests that we expect to see declining numbers in association with the further fragmentation and loss of habitat in both Kenya and Tanzania.
Colobus in Africa
Colobine monkeys (Family Cercopithecidae; Subfamily colobinae) are found in Africa and Asia. African species include the Olive, Red and Pied. The Pied colobus include the Black, Western Pied, Angola Pied, Geoffroy's Pied and the Guereza.
|Angolan Black and White Colobus||Abyssinian Black and White Colobus||Tana River Red Colobus||Zanzibar Red Colobus|
|Colobus angolensis ssp palliatus||Colobus guereza ssp occidentalis||Procolobus badius ssp tephrosceles||Procolobus badius ssp kirkii|
Note: Taxonomy of many primate species is disputed throughout the world. This is based on the World Conservation Union (ICUN) Status Survey and Conservation Primate Specialist Group.
As are all colobus, the Angolan colobus monkey is diurnal, they have flattened nails, pads on their buttocks, and their hind legs are longer than their fore limbs. These are typical characteristics of old world monkeys. However, the specific features of Colobines are due to their unique dietary adaptations.
Colobus eat mostly leaves (and some fruits and flowers), have no cheek pouches, are arboreal (live in the tree canopy and rarely come down to the ground) and have a light-weight bone structure and elongated limbs - making it easier to leap from branch to branch. Additionally, the Colobus have no thumbs though they retain an opposable big toe. "Colobus" in fact acquired their name from the Greek word "kolobos" meaning maimed or mutilated. The reduction of the thumb is an adaptation to arboreal living as the fingers have become aligned into a single, narrow curved arc that allows the hand to act as a flexible hook.
Their stomach is large and has three chambers, which carries specific bacteria that helps to ferment and digest leaves, similar to rumination of, for example, cows. The majority of their diet is made up of young and mature leaves - 46 species eaten but only five species make the greatest proportion of their diet. Because of the poor nutritional quality of their food, they browse intensively for many hours each day. They digest two to three kg of leaves per day (one third of their full body weight), and also eat seeds, unripe fruits and flowers. Some species of Colobus are known to eat soil, clay and charcoal which is thought to assist in the digestion of toxic leaves.
In Diani, Colobus are rarely a pest to tourists as they do not eat human food and remain in the tree canopy. Due to their dependence on forests they are a true "flagship" species in which the overall health of the forest can be gauged.
Babies and Families
Infants are born strikingly white, and then turn grey and black and then by three months of age, to the adult colouration of black and white. They are born throughout the year but a birth peak is seen in September and October. Colobine infants are known for their flamboyant colouration, which is remarkably different than the adult. This is considered an adaptation for encouraging 'aunting behaviour' where other females in the group are attracted to the newborn and spend time caring for the young. This supposedly frees up maternal time for feeding. As is known amongst the Colobines, the nutritional value to their diet is low and the stresses of rearing offspring puts enormous pressure on the female. Aunting behaviour thus counteracts the burden of nursing.
Females remain in their natal troops for life. The dominant male defends the territory and troop from predators whereas the dominant female leads the troop. Young males leave their natal troop to start bachelor groups or to travel alone until they are able to take over their own troop.