Eastern black-and-white colobus, Magistrate colobus, Guereza, Abyssinian black-and-white colobus
The mantled guereza (Colobus guereza ), also known simply as the guereza, the eastern black-and-white colobus, or the Abyssinian black-and-white colobus, is a black-and-white colobus, a type of Old World monkey. It is native to much of west central and east Africa, including Cameroon, Equatorial Guinea, Nigeria, Ethiopia, Kenya, Tanzania, Uganda and Chad. The species consists of several subspecies that differ in appearance. It has a distinctive appearance, which is alluded to in its name; the long white fringes of hair that run along each side of its black trunk are known as a mantle. Its face is framed with white hair and it has a large white tail tuft.Show More
The mantled guereza is diurnal and arboreal, found in both deciduous and evergreen forests. It is an adaptable species that can cope with habitat disturbance and prefers secondary forest close to rivers or lakes. Although previously thought only to eat leaves, it also eats seeds, fruits, and arthropods. It is able to digest plant material with a high fibre content with its specialised stomach and may only eat from a few plant species at a time. It is preyed on by birds of prey and some mammals, such as the common chimpanzee and the leopard.
The mantled guereza lives in social groups of three to fifteen individuals. These groups normally include a dominant male, several females, and the offspring of the females. It has a polygynous mating system and copulation is initiated with vocal communication. After a gestation period of just over five months, infants are born with pink skin and white fur, which darkens to the adult coloration by three to four months. The mantled guereza is well known for its dawn chorus, the males' "roar" is a method of long-distance communication that reinforces territorial boundaries. It also makes other vocalization and uses body postures, movements, and facial expressions to communicate.
The mantled guereza is listed as Least Concern by the International Union for Conservation of Nature (IUCN) because it is widespread – although it is locally threatened in some areas, the decline is not great enough to list it in a higher category of threat. However, one subspecies found in Kenya is listed as Endangered. It can survive well in degraded forests and in some areas it is more common in logged areas than unlogged ones. The mantled guereza is also threatened by hunting for bushmeat and for its skin.Show Less
Mantled guerezas are divided into several subspecies, each of which exhibits a unique appearance. However, all of these sub-species have characteristic mantles - long, white colored fringe of fur, stretching across both sides of the trunk, giving these animals their common name, Mantled guerezas. These primates are black-and-white colobuses, belonging to the group of Old World monkeys. A frame of white colored hairs surrounds their face. On their tail, they display a conspicuous, white tuft. And finally, these animals differ from all other Old World monkeys by having a reduced thumb and lacking pouches on their cheeks.
The natural range of this species occupies Equatorial Africa, stretching from Nigeria and Cameroon eastwards to Ethiopia, Kenya, Uganda, and northern Tanzania. The Mantled guerezas are generally found in forest and savannah woodlands as well as highland and montane forests. Overall, they inhabit deciduous and evergreen forests of their range. Other suitable types of habitat include both primary and secondary forests, more precisely, gallery, upland forests as well as riparian forests. They are typically found close to fresh or brackish water bodies such as rivers and lakes.
As social primates, Mantled guerezas form units of 8-15 individuals, consisting of a single adult male as well as 3-4 breeding females with their infants and juveniles. From time to time, these groups may contain up to several males, which temporarily join the group. These primates spend most of their time in trees, occasionally climbing down to find food and travel. These monkeys lead a diurnal lifestyle, spending up to 50% of the day resting. Mantled guerezas leave their sleeping sites after dawn, returning only at dusk to sleep again. Along with resting, they spend a lot of time looking for food and traveling. However, even during the active daytime hours, they usually alternate feeding and traveling activities with long periods of resting. A small remaining amount of time is typically spent grooming, greeting, playing, and watching out for predators.
Mantled guerezas are herbivores (folivores, frugivores) and their diet is generally composed of leaves and fruits. However, they have a rather diverse diet and will consume bark, wood, seeds, flowers, petioles, lianas, aquatic plants, arthropods, soil as well as occasional concrete of buildings.
Mantled guerezas are polygynous animals. A single adult male mates with a group of females otherwise called 'harem'. They don't exhibit a certain mating season but are known to breed at intervals of 20-22 months. The gestation period lasts for 158 days, yielding one baby, which is cared for and handled by the members of its natal group (primarily - females) during the first few months of its life. During this stage of development, the infant travels clung to the chest of its mother. By 20 weeks old, the young monkey will begin moving on its own. And finally, it's totally independent and weaned at 50 weeks old. Males of this species are reproductively mature at 6 years old, whereas females are able to produce offspring of their own at 4 years old.
The Mantled guerezas are primarily threatened by the destruction of their habitat. These animals also suffer from large-scale hunting and capture for sale and trade: their skin serves as material for trimming coats, dresses, circular rugs, and wall hangings.
The Mantled guerezas are widespread and locally abundant. According to the New England Primate Conservancy, the total population size of the Mantled guerezas in the wild is around 2,000 individuals, including 400 monkeys in the Diani Beach area (Kenya). Currently, Mantled guereza monkeys are classified as Least Concern (LC) on the IUCN Red List.
Being herbivores, these monkeys may play an important role in the structuring of plant communities. They may also affect predator populations, as items of prey. The specially adapted stomach of these primates is sacculated and contains certain bacterial colonies, which help them digest cellulose, found in leaves, unripe fruit, and seeds that compose the major part of their daily diet. Due to this particular structure of their stomach, the Mantled guerezas occupy a unique ecological niche in the local ecosystem, which distinguishes them from many other primates.