Bioko Pennant’s Red Colobus

Vital Stats

  • Latin Name: Procolobus pennantii
  • Bioko's Endemic Species: Procolobus pennantii
  • IUCN Status: Critically Endangered
  • Captive Population: None, according to ISIS.


Pennant's red colobus is a noisy, slow monkey with a small head, long legs and a round belly. It is covered in shaggy hair in shades of maroon, orange, white and black. The former species Procolobus pennantii remains in only a few small patches: in eastern Congo along Congo river (ssp. bouvieri); on Bioko Island (ssp. pennantii); and in the Niger Delta region (ssp. epieni). It's disappearance from the remainder of Central West Africa is a mystery. Some sort of species-specific disease is the most likely culprit, though climatic changes, competition by other primates, and past hunting by humans may have been the cause. Following Groves (2007), the three subspecies were raised to the species level and the Bioko Pennant's red colobus is recognized as the first strict Bioko endemic primate species (Procolobus pennantii).

Red colobus on Bioko Island typically live in large diffuse troops, easily located in the forest by their noisy vocalizations, a variety of barks, squawks, and other barnyard-like noises. Many people find the vocalizations of distraught red colobus very similar to chimpanzee vocalizations. Females tend to stay with the same group throughout their lives while males may travel from group to group. Acrobats in the trees, red colobus span wide gaps by leaping from one slim branch to another or by using the elasticity of a branch to catapult themselves between trees. Red colobus eat fruits, seeds, and foliage in two concentrated feeding sessions in the morning and evening.

The red colobus was first named to science by Waterhouse from a Bioko Island specimen in 1838. In 2006 it was named one of the World's 25 most endangered primate species by Conservation International. It's range on Bioko Island is probably limited to the south western corner of the island and the nearby Gran Caldera, although a few animals may remain on Pico Basile and in the south eastern corner. Red colobus are easy to kill by shotgun (for the bushmeat market in Malabo) and as a result they are rapidly declining in numbers on the island. Recent taxanomic evidence suggests that the Bioko Island red colobus is most closely related to Preuss's red colobus which inhabits the nearby Cameroonian mainland. However, the division between the two lineages may extend to well before Bioko Island's separation from the mainland.

Cronin, D. T., D. Bocuma Meñe, T. B. Butynski, J. M. E. Echube, G. W. Hearn, S. Honarvar, J. R. Owens, and C. P. Bohome. 2010. Opportunities Lost: The Rapidly Deteriorating Conservation Status of the Monkeys on Bioko Island, Equatorial Guinea (2010). A Report to the Government of Equatorial Guinea by the Bioko Biodiversity Protection Program, Drexel University, Philadelphia, PA. 40pp.

Groves, C. P., 2007: The taxonomic diversity of the Colobinae of Africa. Journal of Anthropological Sciences, 85: 7-34.