The red-tailed guenon is a species of Old World monkey native to the tropical forests of east-central Africa.
Red-tailed guenons are exceptionally fast and active monkeys that call to each other with bird-like chirps and twitters. They also communicate through an extensive repertoire of visual cues.
They live together in family groups that range in number from about 7 to 35. These groups are comprised of one adult male and several females and juveniles. They feed together during the day and sleep together in one or two neighboring trees at night. Males living singly are most likely between groups, having been dismissed by one and awaiting an opportunity to lead another. At times, large numbers of red-tails may be seen together and this likely indicates several family groups coming together to share food where it is plentiful.
Red-tailed guenons are most active in the early morning and late evening. They prefer to stay in the mid-level tree canopy, where they feed on the leaves, shoots, fruit, and flowers of many different trees and shrubs. While moving through the trees, they use their exceptionally long tails for balance.
In areas where forest borders agricultural land, red-tailed guenons learn quickly how and when to raid nearby farms. In some places, they have learned that the best time to raid a farm is under cover of darkness. They sample many kinds of crops including banana, millet, maize, bean, pumpkin, pineapple and passion fruit, and they also dig up roots. When raiding, they stuff their cheek pouches and often stop to peer around to see if they’ve been spotted.
Like all species of guenon, red-tailed guenons have unique facial markings and, in forests full of other monkey species as well, they recognize their own kind by these markings. Red-tailed guenons have reddish fur and tails, and black faces with blue fur around the eyes and white cheek patches. Depending on the subspecies, the nose spot is either white, yellow, or black.
Leopards and crowned hawk-eagles are common predators of red-tailed guenons, as are human hunters. When a group of red-tailed guenons is disturbed or detects a predator nearby, the male of the group makes an explosive warning cough. The group may respond by crashing into thick vegetation, making as much noise as possible to alarm the predator, or by going silent, or by trying to descend to the ground and flee.
The male giving the warning usually continues to do so with a series of staccato chirps, alerting the group to the attacker’s every move. When threatened or excited, red-tailed guenons also bob their heads, raise their hind quarters, lash their tails over their heads, and chirp.
Red-tailed guenons mate during the dry season, between December and April. Females give birth to single offspring usually between May and September, after a gestation period of 4 to 5 months. At birth, infant red-tails are covered in woolly grey fur and have nose spots but do not yet have fully distinctive facial coloration. Within about 3 months, they are smaller, paler replicas of adults.
Red-tailed guenons are widespread throughout their range and are listed as a species of least concern by the IUCN, the world’s leading conservation organization. Nonetheless, they are threatened by habitat destruction from agriculture and logging, and by heavy hunting in some parts of their range.