| Aders' Duiker | |
|---|---|
| Conservation status | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Artiodactyla |
| Family: | Bovidae |
| Subfamily: | Cephalophinae |
| Genus: | Cephalophus |
| Species: | C. adersi |
| Binomial name | |
| Cephalophus adersi Thomas, 1918 |
|
The Aders' Duiker (Cephalophus adersi), also known as Nunga in Swahili, Kunga marara in Kipokomo, and Harake in Giriama), is a small forest dwelling Duiker found only on Zanzibar and in a small coastal enclave in Kenya. It is also critically endangered. It is believed by some to be a subspecies of the Red, Harvey's, or Peters's Duiker or a subspecies of a combination of the above.
Contents |
The Aders' Duiker stands at around 30 centimeters tall at the shoulder. Their weight varies greatly depending on geographical location; those in eastern Zanzibar weigh 12 kilograms, while those in the south weigh only 7.5 kilograms. Aders' Duikers have a reddish-brown coat which is grayer on the neck and lighter down the backside and underneath. There is a small red crest running along the head. Aders' Duikers also have small, simple horns of 3 to 6 centimeters. The muzzle is pointed, and the nose has a flat front. The ears measure 7-8.3 cm long, and there is a marked cowlick or whorl of hair on the nape of the neck.
Aders' Duikers live primarily in coastal forests and woodlands in Africa. The species can live in quite dry scrub near the sea or among coral outcrops - in Zanzibar they are restricted to tall thicket forest growing on waterless coral rag . In Arabuko Sokoke (Kenya), Aders' Duikers are most often trapped within Cynometra vegetation, especially on "red soil". C. adersi is sympatric with C. harveyi on the mainland and with C. monticola sundevalli on Zanzibar, although nothing is known regarding their ecological separation.
There are estimated to be around 1,400 Aders' Duikers left in the world. They are threatened by habitat destruction, feral dogs and over-hunting. Aders' Duikers are particularly sought by humans due to their soft skin and sweet meat.
The species is very shy, alert, and sensitive to sound. As a result, common methods of hunting include the brute-force method of driving the Duikers into nets with dogs, or silent ambush at feeding sites.
Aders' Duikers live in coastal forests, thickets and woodlands where they eat flowers, leaves, and fruit which has fallen from the forest canopy. The species appears to be diurnal, as it is rarely seen active at night. Typical feeding patterns are from dawn to around 1100 hours, which is followed by a period of rest and rumination. At about 1500 hours Aders' Duikers generally become active, and will continue foraging until nightfall.
They are generally solitary or found in small groups, such as pairs or trios. They feed primarily on fallen flowers, fruits, and leaves - often picking up scraps dropped by monkeys and birds foraging in the trees. (Swai 1983; Imani pers. comm. to Williams 1998)
C. adersi shows a particular dependence on the flowers and berries which grow prolifically from trees common to the area, such as ebony (Diospyros consolataei), kudu berry (Cassine aethiopica) and bush guarri (Euclea schimperi), and bushes such as turkey berry (Canthium spp.) and Polyspheria. In addition to these, they will eat sprouts, buds, and other fresh growth found at ground level. This Duiker species can apparently manage without drinking, getting most of the hydration they need from their diet.
According to Williams et al. (1996), the Duikers have extremely specific habitat requirements, being found only in areas of old growth thicket, with the highest population densities (11.4±5.18 per km²)[2] recorded in relatively undisturbed high thicket. However, Kanga (1999) did report some Aders' Duikers in secondary thicket. In the Arabuko-Sokoke Forest in Kenya, Aders' Duikers inhabit regions of Cyanometra forest.
Not much is known of the Aders' reproductive habits although it is speculated that they breed all year long. The population in Zanzibar had declined from 5000 in 1983 to 640 in 1999, and it is thought it will probably continue to decrease rapidly. In Kenya the Duiker is present at very low densities, though the decline is probably not as severe as the other population..
Several conservation plans have been made, and a captive-breeding program has been proposed.