Animal Info - Saola

(Other Names: 武廣牛, ベトナムレイヨウ (サオラ), Vietnamesisches Waldrind, Vu Quang Ox, Vu-Quang-Rind)

Pseudoryx nghetinhensis

Status: Critically Endangered


1. Profile (Picture)
2. Tidbits
3. Status and Trends (IUCN Status, Countries Where Currently Found, Population Estimates, History of Distribution, Threats and Reasons for Decline)
4. Data on Biology and Ecology (Weight, Habitat, Birth Rate, Diet, Behavior, Social Organization)
5. References


Picture: Saola #1 (9 Kb JPEG); Saola #2 (35 Kb JPEG) (Huffman 2004)

The saola is a forest-dwelling ox weighing about 100 kg (220 lb). All known locations for the species are mountainous with steep river valleys, covered by evergreen or semideciduous forests between 300 - 1800 m (1000 - 6000'), with low human disturbance. Current knowledge indicates that the saola prefers the edge areas of wet lowland evergreen forest habitats and evergreen montane forests. Villagers say that the ox eats the leaves of fig trees and other bushes along riverbanks. The small size of the incisors suggests a browsing diet. It stays in the higher elevations during the wetter summer season, when streams at these altitudes have plenty of water, and moves down to the lowlands during the winter, when the mountain streams dry up. The saola is said to travel in small groups of 2 - 3 animals, rarely up to 6 - 7 animals.

First documented by Western scientists in Vietnam in 1992, the saola has also been found in Laos. It is thought to be restricted to an area of approximately 4000 sq km (1540 sq mi) along the Vietnam-Laos border. All available information indicates that the species is in a clear and protracted decline throughout its small range, and rates of decline are likely to increase rather than decrease. 

The decline of the saola is due to intense hunting pressure, accelerated by continued opening-up of its habitat to increased human access (mainly through road construction).


*** The saola is one of the world's rarest mammals.

*** In May 1992, the discovery of three pairs of horns in the only remaining area of pristine forest in northern Vietnam led to the first documentation by Western scientists of a new species of ox.

*** The saola is shy and apparently never enters agricultural lands. Hunters reported that it was never seen close to villages.

*** Little is known about the saola, due to its relatively inaccessible habitat and relatively recent documentation by Western scientists.

*** The scientific name selected for this species, Pseudoryx nghetinhensis, refers to the two Vietnamese provinces Nghe An and Ha Tinh close to where it was found. This follows the recent custom of naming newly identified mammal species for geographic locations near where they were first found. Such species include: the Truong Son muntjac, named Muntiacus truongsonensis for the Truong Son (formerly "Annamite") range of mountains in Vietnam; the giant muntjac, named Megamuntiacus vuquangensis for the Vu Quang Nature Reserve in Vietnam; the leaf muntjac, named Muntiacus putaoensis for the town, Putao, nearest to where it was found in Myanmar; and the Tainguen civet, Viverra tainguensis, named for the Tainguen Plateau in Vietnam. (Amato et al. 1999, Rozhnov & Pham Trong Anh 1999, Wikramanayake 1999)

*** Saola are shot for their meat. Because of their scarcity, local people place a higher value on saola than on more common species. Hunters were also aware of the intense interest from the world's scientific community, increasing their motivation to capture live specimens. Among local communities, there was some awareness that forest resources were declining, but the general perception was that resources were still plentiful. Moreover, the hunters showed little or no understanding of the principles of resource management of the species that they hunted. Everything that was encountered during hunting trips was shot or captured, if possible. Although the saola was valued by hunters, there seemed to be little concern about its decline or local extinction (Kemp et al. 1997).

Status and Trends

IUCN Status:

Countries Where the Saola Is Currently Found:

2006: Occurs in Laos and Vietnam. (IUCN 2006)

Population Estimates:

[Note: Figures given are for wild populations only.]

History of Distribution:

The saola was first documented by Western scientists in Vietnam in 1992 (WCMC/WWF 1997).  It occurs in forested hills and mountains along the border between Laos and Vietnam. It is currently estimated to occur in less than 15 forest blocks in the two countries. The species is absent from small forest fragments, and restricted to remote core areas of the larger forest blocks. The number of saola subpopulations is probably about 6 - 15, and none likely numbers more than 50 animals. It is likely that total saola numbers are fewer than 250 mature individuals. The population is also highly dispersed, and fragmentation is worsening. Saola numbers may be so low that no viable populations remain. (IUCN 2006)

Distribution Map #1 (10 Kb GIF) (Huffman 2004) 
Distribution Map #2 (87 Kb PDF) (IUCN 2006) 

Threats and Reasons for Decline:

The saola population is declining at a high rate, probably due to the intensive, non-specific hunting of most larger species of wildlife throughout the saola's range (spurred by commercial demand for bushmeat and Asian traditional medicine). This is augmented by habitat loss due to logging and forest clearance, all of which are accelerating due to recent and widespread expansion of road networks in the species' range. (IUCN 2006).

Data on Biology and Ecology


The saola weighs about 100 kg (220 lb).


The saola's habitat requirements appear to be highly specific; i.e., moist evergreen forests with little or no dry season. Thus, many areas within the presumed range in both Laos and Vietnam are not suitable, due to the predominance of monsoonal and limestone forests. The saola's altitude range is uncertain, but there is no indication that it occurs above 1,000 m (3300'). Most forest below 400 m (1300') within the saola's presumed range has been lost, and a high proportion of the remaining forest is higher than 1000 m (3300'). (IUCN 2006)

The saola occurs in the Annamite Range Moist Forests and the Eastern Indochina Dry & Monsoon Forests Global 200 Ecoregions. (Olson & Dinerstein 1998, Olson & Dinerstein 1999)

Birth Rate:

Pregnancy with a single fetus has been documented, and information from local informants suggests that is the usual case (Robichaud 1998, cited in IUCN 2006).


Villagers say that the saola eats the leaves of fig trees and other bushes along riverbanks. The small size of the incisors suggests a browsing diet (Dung et al. 1994).


It stays in the higher elevations during the wetter summer season, when streams at these altitudes have plenty of water, and moves down to the lowlands during the winter, when the mountain streams dry up.

Social Organization:

The saola is most likely solitary, and possibly territorial (IUCN 2006).


Amato et al. 1999, Dung et al. 1994, Focus 1996, Huffman 1999g, Huffman 2004, IUCN 1996, IUCN 2000, IUCN 2002, IUCN 2003a, IUCN 2004, IUCN 2006, Kemp et al. 1997, Mallon & Kingswood 2001, Olson & Dinerstein 1998, Olson & Dinerstein 1999, Rozhnov & Pham Trong Anh 1999WCMC/WWF 1997, Wikramanayake 1999

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Last modified: May 28, 2006;

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