Saola: The Endangered Asian Unicorn

Bill Robichaud/Global Wildlife Conservation

The saola (Pseudoryx nghetinhensis) was discovered in May of 1992 by surveyors from the Ministry of Forestry of Vietnam and the World Wildlife Fund who were mapping the Vu Quang Nature Reserve of north-central Vietnam. "The team found a skull with unusual long, straight horns in a hunter's home and knew it was something extraordinary, reports the World Wildlife Fund (WWF). "The find proved to be the first large mammal new to science in more than 50 years and one of the most spectacular zoological discoveries of the 20th century."

Commonly referred to as the Asian unicorn, the saola has rarely been seen alive since its discovery and so is already considered critically endangered. Scientists have categorically documented saola in the wild on only four occasions to date.

WWF has prioritized the saola's survival, saying, "Its rarity, distinctiveness, and vulnerability make it one of the greatest priorities for conservation in the Indochina region."


The saola has long, straight, parallel horns that can reach 50 centimeters in length. Horns are found on both males and females. The saola's fur is sleek and dark brown in color with dappled white markings on the face. It resembles an antelope but is more closely related to cow species. Saola have large maxillary glands on the muzzle, which are thought to be used to mark territory and attract mates.


Height: about 35 inches at the shoulder

Weight: from 176 to 220 pounds


Saola live in subtropical/tropical moist mountainous environments characterized by evergreen or mixed evergreen and deciduous woodlands. The species seems to prefer edge zones of the forests. Saola are presumed to reside in mountain forests during the wet seasons and move down to the lowlands in winter.


Saola are reported to browse on leafy plants, fig leaves, and stems along rivers.


In Laos, births are said to occur at the beginning of the rains, between April and June. Gestation is estimated to last about eight months.


The lifespan of the saola is unknown. All known captive saola have died, leading to the belief that this species cannot live in captivity.

Geographic Range

Saola inhabit the Annamite Mountain Range along the northwest-southeast Vietnam-Laos border, but low population numbers make distribution particularly patchy.

The species is presumed to have been formerly distributed in wet forests at low elevations, but these areas are now densely populated, degraded, and fragmented.

Conservation Status

Critically Endangered; CITES appendix I, IUCN

Estimated Population

No formal surveys have been undertaken to determine accurate population numbers, but IUCN estimates the total saola population to be somewhere between 70 and 750.

Population Trend


Causes of Population Decline

The main threats to the saola are hunting and fragmentation of its range through habitat loss.

"Saola are often caught in snares set in the forest for wild boar, sambar or muntjac deer. Local villagers set some snares for subsistence use and crop protection. Recent increases in lowland people hunting to supply the illegal trade in wildlife has led to a massive increase in hunting, driven by traditional medicine demand in China and restaurant and food markets in Vietnam and Laos," according to WWF. "As forests disappear under the chainsaw to make way for agriculture, plantations, and infrastructure, saola are being squeezed into smaller spaces. The added pressure from rapid and large-scale infrastructure in the region is also fragmenting saola habitat. Conservationists are concerned that this is allowing hunters easy access to the once untouched forest of the saola and may reduce genetic diversity in the future."

Conservation Efforts

The Saola Working Group was formed by the IUCN Species Survival Commission's Asian Wild Cattle Specialist Group, in 2006 to protect the saola and their habitat.

WWF has been involved with the protection of the saola since its discovery. WWF's work to support the saola focuses on strengthening and establishing protected areas as well as research, community-based forest management, and strengthening law enforcement.

Management of Vu Quang Nature Reserve where the saola was discovered has improved in recent years.

Two new adjacent saola reserves have been established in Thua-Thien Hue and Quang Nam provinces.

WWF has been involved in the setting up and management of protected areas and continues to work on projects in the region.

"Only recently discovered, saola are already extremely threatened," says Dr. Barney Long, WWF Asian species expert. "At a time when species extinction on the planet has accelerated, we can work together to snatch this one back from the edge of extinction."