Piliocolobus pennantii

92.

Pennant’s Red Colobus

Piliocolobus pennantii

French: Colobe de Pennant / German: Bioko-Stummelaffe / Spanish: Colobo rojo de Bioko

Other common names: Bioko Red Colobus

Taxonomy. Colobus pennantii Waterhouse, 1838,

Equatorial Guinea, Fernando Poo (Bioko) Island.

Modern taxonomic arrangements of the colobus monkeys either divide the red colobus and the Olive Colobus into two genera, Piliocolobus and Procolobus, respectively, or consider them to belong to one genus, Procolobus, with two subgenera (Procolobus for the Olive Colobus and Piliocolobus for the red colobus). We follow here C. P. Groves in his publications of 2001 and 2007 in using two genera. Monotypic.

Distribution. Bioko I (Equatorial Guinea), now mainly restricted to the SW.

Descriptive notes. Head-body c.62 cm (males) and c.64 cm (females), tail ¢.60 cm (males) and c.66 cm (females); weight 9 kg (males) and c.5-8 kg (females). Pennant’s Red Colobusis a rather large, short-tailed species. Photographs taken in the wild suggest that adult males are large and robustly built. In many respects, Pennant’s Red Colobusis similar to Bouvier’s Red Colobus (P. bouvieri), but it is darker, with speckled red and black, almost a solid black, on shoulders, becoming bright red on flanks. Underparts are pale reddish-white to white. Hands and feet are contrastingly black, this tone extending some way up on limbs. Tail is black above and deep red below. Cheek whiskers are white, and crown is black. There is a prominent tuft at the base of each ear. Face is black. Scrotum is not conspicuous, and the clitoris is prominent. Teeth are relatively small, skull is generally narrow, facial skeleton is long, and muzzle is broad. A mtDNA study placesit close to its mainland neighbor, Preuss’s Red Colobus (P. preussi), but its vocalizations are distinct.

Habitat. [.ow and montane forest from sea level to at least 1500 m, and perhaps even 1800 m. Southern forests on Bioko Island, where Pennant’s Red Colobus is most common, receive very abundant rainfall, some areas exceeding 10,000 mm/year.

Food and Feeding. Diets include young leaves and mature leaves, fruit, flowers, buds, and possibly seeds.

Breeding. There is no information available for this species.

Activity patterns. Pennant’s Red Colobusis diurnal and arboreal.

Movements, Home range and Social organization. Pennant’s Red Colobus has never been studied in the wild. Its ranging behavior is unknown. Groups contain 5-30 individuals, with 1-3 adult males. Females travel alone and are probably the sex that disperses from natal groups. Humans are the only predators on Bioko Island; potential predators of red colobus on the mainland, such as crowned eagles (Stephanoaetus coronatus), Leopards (Panthera pardus), and Chimpanzees (Pan troglodytes), do not occur on Bioko Island.

Status and Conservation. CITES Appendix II. Classified as Endangered on The IUCN Red List (as Procolobus pennantii). Pennant’s Red Colobusis listed as Class B in the African Convention on the Conservation of Nature and Natural Resources. Its total distribution is less than 500 km?®, and there are probably less than 5000 individuals remaining. In 2006, G. Hearn and colleagues estimated a 45% decline in numbers between 1986-2006 due mainly to heavy hunting. It was estimated that more than 550 individuals were killed in 2004 alone. Pennant’s Red Colobus occurs in Gran Caldera and Southern Highlands Scientific Reserve. It maystill occur in Basilé National Park, but it has not recorded there since 1980s. Shotgun hunting has been banned on Bioko Island, but the ban has not been strongly enforced.

Bibliography. Butynski & Koster (1994), Gonzalez-Kirchner (1997), Groves (2001, 2007b), Grubb et al. (2003), Hearn & Morra (2001), Hearn et al. (2006), Oates (2011), Struhsaker (2000, 2010), Ting (2008).