Black colobus  (Colobus satanas)

The black colobus is one of the ten most threatened primate species in Africa (3). It is a large, heavily built monkey, with a glossy black coat and longer hair around the face and shoulders (2) (4). The hairs on its crown are semi-erect and point forward on the forehead (2). A unique feature of all Colobus monkeys is the lack of thumbs, in fact Colobus means ‘docked' in Greek. As they leap through their forest habitat, the vulnerability of the thumb to injury is thought to outweigh the advantages of retention (2). Unlike all other species from the Colobus genus, in which the infant is born with a pure white coat, black colobus infants have brown coats (3).

Occurs in central western Africa. There are two subspecies of the black colobus; the Gabon black colobus (C. s. anthracinus) occurs in Equatorial Guinea, east and south-west Cameroon; south-west Gabon and probably west Congo; the Bioko black colobus (C. s. satanas) is found only on Bioko Island, Equatorial Guinea (1).

The black colobus inhabits forests in coastal, mountainous and swampy regions (4).

Black colobuses are tree-dwelling monkeys that live in small troops of 6 to 15 individuals, including one or more adult male (4). The majority of their diet consists of seeds and unripe fruits, but they also consume leaves (5), as all colobus monkeys possess an unusual stomach that enables them to digest leaves more efficiently than other primates (2). Their distinct high-pitched roar can be heard across the forest as dawn breaks (3), and troops can also be heard calling to each other as they prepare to move or as they arrange their night time sleeping positions (2).

Numbers of black colobus monkeys are declining; the result of both hunting and habitat destruction (3). The black colobus is a popular target for hunters, and is widely hunted with shotguns or bows and arrows (5). On Bioko Island, where bushmeat is a vital source of protein and cash for the locals, surveys indicate that the black colobus is becoming scarcer and is probably being hunted to dangerously low numbers (6). The black colobus appears to be more sensitive to habitat disturbance than other Colobus species and is rare or absent in forests that have been logged (3). This has resulted in the black colobus disappearing from many areas (7). Even protected areas in which the black colobus occurs are not safe from habitat degradation; for example, the Gamba Reserve complex is being impacted by unsustainable logging, agriculture and oil exploration (3) (8).

The Bioko black colobus population is found entirely within two protected areas on Bioko Island (9) (10), and the Gabon black colobus has been recorded in three protected areas; Dja Reserve, Cameroon; Lopé Reserve, Gabon and Gamba Reserve complex, Gabon (3) (10). In 1986, the IUCN/SSC Primate Specialist Group compiled an Action Plan for African Primate Conservation in which a number of measures were outlined for the conservation of the black colobus. This plan was revised and the conservation recommendations reviewed in a 1996 publication. Some progress has been made since 1986, but further actions were suggested. This included continued efforts to survey and develop the Dja Reserve and fully protect a core area of the Lopé Reserve. In addition, it was recommended that a management plan was developed for the Gamba Reserve complex, which included measures to reduce the impact of oil exploration occurring in the area (3). Working with local people in Bioko Island to find alternatives to bushmeat is also an urgent priority (6), to ensure the continued survival of the endangered Bioko black colobus.

For further information on conservation on Bioko Island see:

• Bioko Biodiversity Protection Program:
  www.bioko.org

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
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