Bay Colobus

Forming large polyandrous groups of between 12 and 80 individuals (1), the red colobus is diurnal (6). It spends the day moving through the top of the canopy looking for leaves, shoots, fruits, and fungi. It has a complex stomach divided into sacs, due to its diet. In the upper chamber of the stomach, foliage is fermented by bacteria, and once in the lower chamber it can be digested by acid. The stomach is particularly large so that it can take the large quantities of this low value food that are needed to provide the red colobus with the necessary energy and nutrients to survive. More than a quarter of the body weight of an adult can be attributed to the food in its stomach (6). Although not territorial, larger groups tend to have dominance over smaller groups when interactions occur. Mixed-sex groups contain more females than males, leaving bachelor groups of between 8 and 40 males. When ready to mate, females develop swollen genitals and will present to males to encourage mating. Each female may mate with many males, producing just one offspring every two years. Infanticide can occur, but the reasons for this are not fully understood. Once weaned, both males and females will leave the group, but females will join another mixed-sex group, whereas males may join a bachelor group. A social monkey, the red colobus conforms to a hierarchy, crouching to communicate submission, which may lead to 'social' mounting, not to mate, but as a prelude to social grooming (5).

The larger issues of habitat loss and the bushmeat trade underscore the red colobus' fight to exist. Both these problems rely on wide-ranging social and political change for their solution, and much is being done to counter them. Miss Waldron's colobus was declared extinct in 2000, becoming the first primate to go extinct in at least 200 years. However, the scientists who announced its extinction obtained evidence in 2004 of its possible existence, consisting of a tail, a skin and a photograph from hunters, providing new hope. The IUCN continue to classify this subspecies as Critically Endangered, since it has not satisfied the criteria stating that it is beyond reasonable doubt that the last individual has died (8).

The red colobus, like other colobus species, has just a bump in place of the thumb, indeed, colobus means 'docked' in Greek, but the other fingers are particularly long. This monkey differs from other colobus species as the fur is of even length over the whole body, with no tufts of longer fur. Whilst the subspecies differ in size and colouration, they are mainly black, grey or brown above with red or chestnut arms, legs and head (2). Around the pubic area the fur is white, and juveniles of both sexes have female-like genital swellings, possibly to prevent mature males evicting young males before they have matured (5). The red colobus does not have cheek pouches (6). Taxonomic relationships within this species, and with other taxa of red colobus, are widely debated by experts and require clarification.

The red colobus is found in tropical and gallery rainforests in all levels of the canopy (5).

The red colobus is found across much of Africa but the subspecies are confined to certain areas, many of which overlap. The Lomami red colobus (P. b. parmentieri), the Kisangani red colobus (P. b. langi), the Foa red colobus (P. b. foai), and the Kahuzi red colobus (P. b. lulindicus) are all found only in the Democratic Republic of Congo. Elliot's red colobus (P. b. ellioti) is also found in the Democratic Republic of Congo, and is thought to be extinct in Uganda. Miss Waldron's red colobus (P. b. waldronae) was found in Côte d'Ivoire and Ghana but has not been seen alive since 1978 (3). However, recent evidence of a tail, a skin and a photograph suggest that a handful of individuals have remained undetected to this point in the extreme southeast of Ivory Coast (7). The bay colobus (P. b. badius) is found in the western Ivory Coast, Liberia and Sierra Leone (1). Temminck's red colobus (P. b. temminckii) is found in Gambia, northern Guinea, Guinea-Bissau and southern Senegal (1) (3).

The red colobus is classified as Endangered (EN A1cd + 2cd, B1 + 2abc) on the IUCN Red List 2004 (3) and is listed on Appendix II of CITES (4), both as Procolobus badius. Subspecies: the bay colobus (P. b. badius) and Temminck's red colobus (P. b. temminckii) are classified as Endangered (EN A2cd + 3cd + 4cd), and Miss Waldron's red colobus (P. b. waldronae) is classified as Critically Endangered (CR A1c, C2a, D) on the IUCN Red List 2004 (3). The IUCN also recognise a further five subspecies: the Lomami red colobus (P. b. parmentieri), Elliot's red colobus (P. b. ellioti), the Kisangani red colobus (P. b. langi), the Kahuzi red colobus (P. b. lulindicus), and the Foa red colobus (P. b. foai), all classified as Data Deficient (DD) (3). However, recent scientific thought is that these colobus do not belong to Piliocolobus badius, but should be included as subspecies of a different species, P. foai (1).

Although hunting of the red colobus is illegal, it is still very common, with red colobus forming a fair proportion of the bushmeat trade. Compounding this major threat is the loss of huge tracts of forest, particularly along the Ivory Coast, where 85% of original forest cover has been lost (8).