Wild horse species 'in peril'

Africa's wild asses are critically endangered
(Copyright Patricia D Moehlman 1998)

By Alex Kirby BBC News Online environment correspondent

Immortalised in ancient cave paintings, the horse has fascinated humans for thousands of years.

Predictably, though, it is principally human activities that are placing the few remaining wild horses under increasing pressure.

Zebras, asses and horses can serve as 'flagship' species

Dr Patricia Moehlman

Conservationists, alarmed at the prospects for the seven species of horse, ass and zebra that survive in the wild, are launching an action plan designed to safeguard their future.

It summarises current knowledge on their biology, ecology and conservation status.

The plan is entitled Equids: Zebras, Asses and Horses - Status Survey And Conservation Action Plan. It is the work of the equid specialist group of the World Conservation Union (IUCN).

Dr Patricia Moehlman, who chairs the group, said: "Most of the endangered equids live in desert and savanna ecosystems. These habitats are not rich in biodiversity, but do contain unique and endemic animals and plants.

Hanging in there

"Zebras, asses and horses can serve as 'flagship' species for the conservation of these ecosystems.

"The arid homes of many equids are also home to human populations that face the same extreme environmental pressures. The benefit to wildlife of involving local pastoralists in conservation management is likely to be significant."

Grevy's zebra
(Copyright Patricia D Moehlman 1985)

The seven equid species are the African and Asiatic wild asses, the kiang (a wild ass from Tibet), Przewalski's horse, and three zebra species - Grevy's, mountain and plains zebras.

Most are threatened, and are classified as endangered or vulnerable on IUCN's Red List of Threatened Species.

One species, Przewalski s horse, is classified as extinct in the wild on the Red List.

It can breed with domestic horses and produce fertile offspring, but its possession of certain distinct chromosomes means it differs more from its domestic relatives than any two domestic horses do from each other.

There are also differences in appearance: for example, Przewalski's horses shed their tail and mane hair annually, unlike domestic horses.

The first visual records of this species are more than 20,000 years old - cave paintings, engravings, and decorated tools from Italy, western France, and northern Spain.

Numbers of Przewalski's horse declined dramatically after 1945, and only small groups were reported in the next few years. Possible causes include hunting, military activities, and increasing land use pressure.

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Inching back

The last confirmed sighting in the wild was in 1969, when a solitary stallion was seen by a Mongolian scientist in the Gobi desert. Today, Przewalski's horse survives thanks to captive breeding.

The kiang, Tibet's wild ass
(Copyright Patricia D Moehlman 2000)

The only free-ranging populations are those re-introduced to Mongolia since 1992. That autumn the first recorded birth occurred of a Przewalski's horse in Mongolia since their extinction in the wild.

The mountain zebra historically ranged from southern South Africa through Namibia and into western Angola.

It is classified as endangered on the Red List: it is believed to have declined by at least 50% in 10 years (three generations). Two subspecies are known (Equus z. zebra and E. z. hartmannae).

Risk of hybrids

Although it suffered through excessive hunting and loss of habitat to agriculture, numbers of Equus z. zebra are now gradually building up through conservation programmes.

Major threats to the zebras' survival include the risk of cross-breeding between the two subspecies, which could mean the loss of genetic diversity.

Other dangers include drought, and the relatively small numbers left in the wild, which means the loss of a single population could reduce global numbers by around 30%.

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