Chlorocebus aethiops (Linnaeus, 1758)

Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Cercopithecidae, Handbook of the Mammals of the World – Volume 3 Primates, Barcelona: Lynx Edicions, pp. 550-755 : 672

50.

Grivet Monkey

Chlorocebus aethiops

French: Grivet d'Ethiopie / German: Athiopien-Griinmeerkatze / Spanish: Mono tota

Other common names: Grivet, Vervet Monkey

Taxonomy. Simia aethiops Linnaeus, 1758 ,

Sudan, Sennaar.

C. aethiops intergrades with C. pygerythrus in south-western Ethiopia; it is unclear if the resulting hybrids are the form originally described as C. a. zavattari. Some authors recognize the form matschiei from the western highlands of Ethiopia as a distinct subspecies. It is said to have a more fawn-to-russet back than typical C. aethiops , with the internal aspects of the limbs more gray. Its tail is also shorter, with a reduced terminal tuft and reduced tufts at the base. A more likely possibility is that it is merely a population of C. aethiops that has hybridized extensively with C. djamdjamensis . Monotypic.

Distribution. NE Africa E of the White Nile, in Eritrea, Ethiopia (S to the Omo River and E as far as the Rift Valley), Djibouti, SE Sudan (from Khartoum in the N to Mongalla in the S), and E South Sudan; possibly in S Egypt.

Descriptive notes. Head-body 42-60 cm (males) and 30-50 cm (females), tail 46-76 cm (males) and 41-66 cm (females); weight 3.1-6.4 kg (males) and 1.5-4.9 kg (females). The Grivet Monkey is grizzled-olive above with a white underside, grayish limbs, and a yellowish-grizzled-olive crown. Face is black, with a fine white moustache and fluffy, elongated cheek fringes, the latter continuous with a narrow white brow band. Hands and feet are pale, with light brown digits. There is a white tuft at the base of the tail. Scrotum is sky-blue.

Habitat. Savanna and open woodland and often forest-grassland mosaic habitats. Grivet Monkeys are normally in close proximity to rivers. They are extremely adaptable and are found in rural and urban environments; the latter may increase risk of problems arising from human-wildlife conflict in cultivated areas.

Food and Feeding. Grivet Monkeys eat mainly grasses, fruits, flowers, bulbs, roots, young leaves, eggs, and animal prey. The latter category includes invertebrates, chameleons, fledgling birds, and small mammals such as rodents and even galagos ( Galagidae ). They are especially fond offigs and other fruiting trees, and in some areas, they are heavily dependent on parts of thorn trees ( Acacia , Fabaceae ), including seeds, gums, thorns, and bark. Grivet Monkeys raid crops and are considered a major pest in some parts of their distribution. If not hunted, they become habituated to humans and even take handouts from tourists.

Breeding. Female Grivet Monkeys show no sexual swelling. A single offspring is born after a 6month gestation. Individuals may live more than 30 years.

Activity patterns. Grivet Monkeys are diurnal and mainly terrestrial.

Movements, Home range and Social organization. Grivet Monkeys live in groups of 6-20 individuals, averaging a dozen. Behavioral and genetic studies indicate that males transfer among groups, while females tend to remain in their natal groups. Like other members of this genus, Grivet Monkeys have a complex social structure; most groups have multiple adult males that are usually outnumbered by adult females.

Status and Conservation. CITES Appendix II. Classified as Least Concern on The [UCN Red List. Grivet Monkeys are listed as Class B in the African Convention on the Conservation of Nature and Natural Resources. They are often common and are able to adapt to a wide variety of habitats throughout their distribution. There are presumed to be no major threats. It is known to occur in one protected area: Awash National Park in Ethiopia. Genetic analyses of some populations in Ethiopia indicate a low level of variability compared with many other cercopithecines, suggesting the possibility that populations of Grivet Monkeys have undergone fluctuations in size in recent times as a result of climate change.

Bibliography. Butynski (2002b), Dandelot & Prévost (1972), Dorst & Dandelot (1970), Groves (2001), Kingdon (1997), Kingdon & Butynski (2008b), Oates (2011), Shimada (2000), Shimada & Shotake (1997), Turner (1981), Zinner, Pelaez & Torkler (2002).

Figures

49. Patas Monkey (Erythrocebus patas), 50. Grivet Monkey (Chlorocebus aethiops), 51. Tantalus Monkey (Chlorocebus tantalus), 52. Green Monkey (Chlorocebus sabaeus), 53. Malbrouck Monkey (Chlorocebus cynosuros), 54. Vervet Monkey (Chlorocebus pygerythrus), 55. Bale Mountains Monkey (Chlorocebus djamdjamensis), 56. L’Hoest’s Monkey (Allochrocebus lhoesti), 57. Preuss’s 9 Monkey Allochrocebus (null), 58. Sun-tailed Monkey (Allochrocebus solatus)

Distribution. NE Africa E of the White Nile, in Eritrea, Ethiopia (S to the Omo River and E as far as the Rift Valley), Djibouti, SE Sudan (from Khartoum in the N to Mongalla in the S), and E South Sudan; possibly in S Egypt.