The vervet is a medium to large-sized, black-faced monkey common in East Africa. There are several subspecies of vervet monkeys, but generally, the body is greenish-olive or silvery-grey. Its face, ears, hands, feet, and tail tip are black, but a conspicuous white band on the forehead blends in with the short whiskers. 

The males are slightly larger than the females and easily recognized by turquoise-blue genital balls and red penis. Combined with their underside white fur, this striking colouration is referred to as the “red, white, and blue display”.

Associated with a wide variety of habitats, it is the only guenon you’re likely to see outside of Uganda’s forests, and it is the most numerous monkey species in the world.

Vervet Monkey Behaviours

Vervets build stable complex social troops of about 10 to 50 individuals, mainly adult females and their offspring, and the troop follows a strict social hierarchy among its troop members. Males leave their troops at least once in their life when they mature into adults, but the transition process can be dangerous because troops dislike immigrants.

The hierarchical social system maintains feeding, mating, fighting, friendships, and survival cohesion but is also essential for grooming and leisure. A vervet monkey will spend several hours each day removing parasites, dirt, and other materials from one another’s fur. In the hierarchy, dominant monkeys get the most grooming.

Newborns will spend their first week clinging to their mother’s stomach, and after the third week, begin to move about by themselves and play with other young monkeys. 

Subadult females are very interested in the troop’s infants, babysitting and grooming them every chance. Researchers have observed female vervets getting unrestricted access to the babies.

Vervet monkeys are primarily vegetarian, feeding on leaves, young shoots, bark, fruit, flowers, bulbs, grass, roots, and seeds. They supplement their vegetarian diet with insects, eggs, grubs, birds, and sometimes rodents and hares. 

These monkeys have the characteristic cheek pouches like other members of the superfamily Cercopithecoidea, allowing them to forage and store food later.

Vervet monkeys move quadrupedally (on all fours) and are equally as comfortable on the ground as in the trees. 

They are semi-terrestrial and semi-arboreal, spending time feeding and travelling on the ground during the day and retreating to the trees to sleep at night. 

Vervet Species Found in Uganda

The vervet monkey is also known as the green, tantalus, savanna and grivet monkey. More than 20 races are recognized, and some authorities group these races into four distinct species.

At least four Vervet monkey races are found in Uganda:

1. The black-faced vervet (C. a. centralis),
2. Naivasha vervet (C. a. callidus),
3. Jebel Mara tantalus (C. a. marrensis) and
4. Stuhlmann’s green monkey (C. a. stuhlmanni).

Vervet monkeys are widespread in Uganda, even outside national parks, but they are absent from forest interiors and Afro-alpine habitats.