The vervet monkey (Chlorocebus pygerythrus), or simply vervet, is an Old World monkey of the family Cercopithecidae native to Africa. The term "vervet" is also used to refer to all the members of the genus Chlorocebus. The five distinct subspecies can be found mostly throughout Southern Africa, as well as some of the eastern countries. These mostly herbivorous monkeys have black faces and grey body hair color, ranging in body length from about 40 cm (16 in) for females, to about 50 cm (20 in) for males. These largely ground-dwelling monkeys are sometimes known collectively as savanna monkeys because they are found in open country or in woodland, as opposed to rainforest. Some vervet monkeys have also adapted to urban environments. Slight variations in appearance occur between species, and there is pronounced variation on coat coloration, from golden-green in green monkeys to darker brown in bale monkeys. Vervet monkeys have pale yellow or white underparts and black faces. The grivet has a white tuft on the tip of the tail and a thin white browband that continues into backswept white whiskers. The vervet has shorter whiskers and black hands, feet, and tail tip. The green monkey has yellow whiskers, grayish hands and feet, and a yellow and black tail. Males of all species possess bluish skin on the abdomen, bright light blue skin.
Breeding occurs from April to June in Africa and year-round in the Caribbean. A single offspring is born after a gestation period of five and a half months. In the wild, females become sexually mature at four years of age, but in captivity they can produce young as early as age two. Males, in contrast, become sexually mature at age five. Members of both sexes rarely live past 10–11 years. The oldest recorded captive individuals lived to 31 years. Vervet monkeys live in larger social groups consisting of several males and 10 or more females and their young. Each troop is led by a dominant male that restricts breeding and other social interactions of subordinate males. The female members of the troop are often related to one another; through their collective support of one male over another, the troop’s females may influence the outcome of a play for dominance. Offspring of different generations remain with one another for years, with elder females assisting their mother in the care of younger siblings of both sexes. Vervet societies are male-dominated, but an age-related dominance hierarchy exists among and between members of both sexes. The International Union for Conservation of Nature’s (IUCN’s) Red List of Threatened Species classifies the bale monkey as vulnerable to extinction but lists all other vervet monkeys as species of least concern (i.e., they are at low risk of extinction). Nevertheless, some vervet monkey populations are subject to intense hunting pressure in areas where people depend on bushmeat. In addition, farmers often regard these monkeys as nuisance animals, because they easily adapt to agricultural environments and raid crops.
