Guereza Colobus (Colobus guereza)
- Type: Mammal
- Family: Cercopithecidae
- Habitat: Deciduous and evergreen forests
- Location: Across central Africa
- Diet: Leaves and fruit
- Average lifespan in the wild: 20 years
- Size: Head and body 20.5-27.5 in (52.1-69.9 cm); tail 20.5-39.4 in (52.1-100 cm)
- Weight: 17.2-20.3 lbs (7.8-9.2 kg) for females; 20.5-29.8 lbs (9.3-13.5 kg) for males
Also known as the eastern black-and-white colobus, or the white-mantled colobus, guereza monkeys have a glossy black coat with beautiful white markings. A mantle of long white hairs adorns their back in a U-shape from their shoulders to the base of their tail. Guerezas have a hairless gray face that is also surrounded by white. Their long tail can be either white or yellowish in color, with a large tuft of white fur at the end. This distinctly marked tail is as long as their head and body combined.
Guerezas have a specialized stomach with two different regions, similar to a cow’s stomach, which helps them digest plant cell walls and fibers from their leafy diet. The upper region of the stomach also contains strains of anaerobic bacteria that aid in digestion. This complex stomach allows guerezas and other colobus monkey species to feed on large quantities of leaves. They also eat fruit. Guerezas live in various habitats across equatorial Africa and as a result their diet can be diverse. Their tough stomachs allow them to digest this variety of food.
Guerezas live in small cohesive groups of 8 to 15 individuals. They spend half their day traveling and feeding. Individual guerezas take turns leading the group to different feeding sites, using quadrupedal motion to travel through the trees. Their hands and feet are adapted especially well for this kind of motion through the forest, grasping and walking on tree limbs. Guerezas also run through tree tops, bounding up and galloping across branches, though they usually make only short leaps across horizontal distances.
Guerezas spend the other half of their day at rest. Between feedings, the group takes breaks to relax and groom each other, and after traveling and feeding during the day, a guereza group will congregate each night before sunset in several adjacent sleeping trees. Most groups consist of one male, several adult females, adolescents, and young. Guereza groups often live close to each other or in overlapping territories, though each group is very territorial. At dawn and dusk, males will “roar” as a way of signaling their territory to other groups.
Did you know: The guereza’s genus name colobus comes from the Greek kolobos, meaning “curtailed” or “mutilated,” appropriate because the animal has only four digits on each hand. Its lack of a thumb may be an adaptation to allow for rapid movement through trees.
Photo by Yoky, Creative Commons license.