Chlorocebus djamdjamensis (Neumann, 1902)

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 : 674-675

55.

Bale Mountains Monkey

Chlorocebus djamdjamensis

French: Grivet des Balé / German: Bale-Griinmeerkatze / Spanish: Vervet de las Montanas Bale

Other common names: Bale Monkey, Bale Mountains Grivet, Djam-djam

Taxonomy. Cercopithecus djamdjamensis Neumann, 1902 ,

Ethiopia, bamboo forest near Abera, east of Lake Abaya, 3300 m.

C. djamdjamensis was formerly listed as a subspecies of C. aethiops and has also been considered a species of the genus Cercopithecus . There is photographic evidence to suggest that hybridization occurs with C. aethiops on the margins of its distribution. Monotypic.

Distribution. W Ethiopia, in the Bale Mts, E of the Rift Valley lakes of Abiata, Shalla, and Zway.

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 Bale Mountains Monkey is a relatively short-tailed species, with long thick fur. Its upper body is deep grizzled-brown, with a creamy-white underside (mixed with gray on chest), grayish limbs, and dark gray hands and feet. Tail is grayish, with an inconspicuous red-brown tuft at its base. Face is black except for a short but very bushy white beard and cheek ruff, and a fine white moustache. A vague white brow band is separated from the cheek ruff by a broad black band running from eye to ear. Scrotum is blue.

Habitat. High-elevation bamboo forest and forest edges at 2400-3000 m above sea level. Although previously described as living only in bamboo forests, new evidence suggests the Bale Mountains Monkey is more flexible in its habitat choice. Nevertheless, it does appear to have rather specialized and unusual habitat requirements, unlike other species of Chlorocebus .

Food and Feeding. The first behavioral and ecological study on the Bale Mountains Monkey was conducted as recently as 2007-2008. They eat primarily young leaves (80-2% in one study). They also eat fruits, seeds, and animal prey (including invertebrates, reptiles, birds, and small mammals). Unlike other species of Chlorocebus , they appear to be specialized for eating bamboo leaves.

Breeding. There is no information available for this species.

Activity patterns. The Bale Mountains Monkey is diurnal and somewhat less terrestrial than other species in Chlorocebus . Feeding accounts for 65-7% of their daily activity budget, with the remaining time spent moving (14-4%), resting (10-7%), and socializing (7-1%).

Movements, Home range and Social organization. The Bale Mountains Monkey lives in groups of up to 50-60 individuals. Their daily movement averages 928 m, and the entire home range is c.15 ha. These figures come from two neighboring groups in one short study. Data indicated that the larger group traveled further each day and occupied a larger home range—a pattern suggesting that scramble competition may have occurred. Vocalizations of the Bale Mountains Monkey are similar to those of the Grivet Monkey ( C. aethiops ).

Status and Conservation. CITES Appendix II. Classified as Vulnerable on The IUCN Red List. The Bale Mountains Monkey is listed as Class B in the African Convention on the Conservation of Nature and Natural Resources. It was presumably more widespread and abundant in historic times. It occurs at low densities and has recently been found in multiple forest fragments in southern Ethiopia, thus extending its distribution to the Guji and West Arsi zones of the Oromia Region and the Sidama Zone of the Southern Nations Nationalities and Peoples Region. Its main threats are ongoing habitat loss, fragmentation, and degradation. Harenna Forest in the Bale Mountains, where individuals are occasionally found, is under threat from encroaching human populations,fire, agriculture, and the removal of forest products. Of special concern is the removal of bamboo, a key resource for the Bale Mountains Monkey. Persecution for crop raiding may also be a problem. Bale Mountains Monkeys may be locally common in some areas (e.g. Odobullu Forest at 6° 87° N, 40° 17° E). Survey work in the Bale Mountains may eventually provide more information about its distribution and population status. It is known to occur in only one protected area, Bale Mountains National Park in Ethiopia, but it is also found in the proposed Harena-Kokosa National Forest Reserve. Although the Bale Mountains Monkey was first named in 1902, it has not been well studied. Until 2008, it waslisted as Data Deficient by ITUCN. This lack of information hampers our understanding of this species and prevents proper conservation action. More detailed studies are needed.

Bibliography. Butynski, Atickem & de Jong (2013), Butynski, Gippoliti et al. (2008), Carpaneto & Gippoliti (1994), Dandelot & Prévost (1972), Groves (2001), Mekonnen, Bekele, Fashing, Hemson & Atickem (2010), Mekonnen, Bekele, Fashing, Lernould et al. (2012), Mekonnen, Bekele, Hemson et al. (2010).

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. W Ethiopia, in the Bale Mts, E of the Rift Valley lakes of Abiata, Shalla, and Zway.