Grevy’s zebra (Equus grevyi) is the largest of the equids (a group that includes horses, asses and zebras) (4). Possessing the same body shape as other equids, Grevy’s zebra has a long head and neck and slender legs resting on a single digit in the form of a hoof (5). The sleek coat is patterned with black and white vertical stripes that are much narrower than those of the plains zebra (Equus burchelli) and persist until above the hind legs where a chevron pattern occurs (6). The horizontal stripes on the legs remain distinct all the way down to the hooves, and the tall, upright mane is also striped in a pattern that continues on from the neck. A wide black stripe along the back is very distinctive and is bordered by white on the rump. Grevy’s zebra has a tan-coloured muzzle with white edges, and the large, rounded ears have one thick black stripe on the back with white tips (2).
Grevy’s zebra has a much more open society than those of other equid species and associations between individuals, other than between a mother and her foal, rarely last for more than a few months (4). Within a single population around ten percent of the mature stallions will occupy territories from which they have sole access to receptive females, although other males are still tolerated within the area, provided females are not in oestrus(2). These territories are patrolled and marked with dung and are the largest of any living herbivore, at up to ten square kilometres(2). Territorial males also vocalise loudly to assert their dominance within the territory (7). Temporary groups of between six to twenty Grevy’s zebras also form and may be either single sex or mixed. Mares become sexually mature at three to four years and give birth to a single foal after a gestation period of 13 months every couple of years (2). Foals are able to stand after a mere six minutes and can run after 45 minutes (6). They remain dependent on their mother’s milk until six to eight months of age (2).
Grevy’s zebra is predominately a grazer, feeding on a variety of grasses, although it will also browse on trees and shrubs during dry conditions (4). Several theories exist as to the function of the stripes of Grevy’s zebra, from camouflage to the dazzling of predators. Recent research has suggested, however, that they may serve a social function and may stimulate grooming (5). It is believed that the equine ancestor of horses, asses and zebras was striped, but these have subsequently been lost during the evolution of the other two groups (5).
Previously found in central Ethiopia, Eritrea, Djibouti, and Somalia, Grevy’s zebra is currently restricted to north-eastern and southern Ethiopia and central and northern Kenya (1)(4)(7). It has not been sighted in Somalia since 1973 and is therefore presumed extinct in this country (4).
Numbers of Grevy’s zebra underwent a dramatic decline in the 1970s when the coat became prized on the international fashion circuit (4). In the 1980s there were 15,000 Grevy’s zebra, with this numbering crashing to around 2,500 today, representing an 83 percent decline in the global population over the last three decades (7). Commercial poaching for skins has since declined due to effective protection measures put in place by Kenya and the Convention on International Trade in Endangered Species (CITES). However, in some areas, Grevy’s zebra is still hunted for subsistence meat and some ethnic groups use their fat for medicinal purposes, such as treating tuberculosis. Habitat loss presents a major threat to the long-term survival of the species as grasslands and water sources have significantly declined due to unplanned grazing by livestock. In addition, there has been a significant, very recent decline in the species in northern Kenya due to disease and drought (7).
Grevy’s zebra is listed on Appendix I of the Convention on International Trade in Endangered Species (CITES), effectively banning international trade in this species (3). It is protected by law in Ethiopia and by a hunting ban in Kenya (1). This rare species also occurs mostly outside protected areas in communally-owned land and ranches where livestock-keeping is the principal livelihood (7). In addition, the Lewa Wildlife Conservancy in Kenya currently holds 370 individuals, representing 15 percent of the world’s total population (8).
Over the last ten years, conservation efforts centred on Grevy’s zebra have significantly increased. In northern Kenya, there are a growing number of community conservancies in key Grevy’s zebra range now managing their land for wildlife conservation. Kenya is currently implementing a five-year conservation strategy for the species through a coalition of conservation organisations dedicated to protecting the species (7).
To help conserve this species by working in the field with Earthwatch, click here.
Embed this Arkive thumbnail link ("portlet") by copying and pasting the code below.