Pseudoryx nghetinhensis, Dung, 1993

Don E. Wilson & Russell A. Mittermeier, 2011, Bovidae, Handbook of the Mammals of the World – Volume 2 Hoofed Mammals, Barcelona: Lynx Edicions, pp. 444-779 : 590-591

14.

Saola

Pseudoryx nghetinhensis

French: Saola / German: Saola / Spanish: Saola

Other common names: Spindlehorn, Vu Quang Ox

Taxonomy. Pseudoryx nghetinhensis Dung et al., 1993 ,

Vietnam.

This species is monotypic.

Distribution. Annamite Mts of Laos and Vietnam.

Descriptive notes. Head-body 143 cm (one adult male), 150 cm (one adult female), tail 16-5 cm (to tip of bone, one adult male), 23 cm (to end of hair, one adult female), shoulder height 95-5 cm (one dead adult male), 84 cm (one live adult female), girth at broadest point around belly 104 cm (one dead adult male), 108 cm (one weakened, pregnant female), ear 10 cm (one adult male), 11-5 cm (one adult female); weight 70-100 kg (estimated). Horns at least 55 cm long measured along the curve and 51 cm measured across the chord. Iris of the eye dark brown, pupil round. Four mammae. The body of this bovid is fairly compact, and the neck relatively long. Pelage is somewhat short (1.5-2.5 cm), mostly straight (curlier on the belly and inner forelegs), and soft. Most of the pelage is medium brown in color, but there are striking white patches on the sides of the face, muzzle, and above the eye; white pasterns, cream and black bands on the tail and rump, a black “chinstrap” over a whitish chin and throat, and a black dorsal midline stripe. Horns are blackish, long, straight, sharply pointed, and with a long bony core. There is apparently no sexual dimorphism, at least in horn length. Saolas possess what may be the largest (in absolute size) preorbital glands of any extant species, measuring 9 cm x 3-5 cm x 1-5 cm deep. Each gland is covered by a muscular flap, which the Saola can raise at will. Captive Saolas have been observed to raise the flaps and expose the glands when scent marking (by rubbing the underside of the flap on edges of rock), when the animal appears nervous, or when exhibiting defensive behavior. There are also small nodules that may be secretory glands (although this function is not confirmed) associated with the white markings on the face. A captive adult female Saola left tracks in modeling clay measuring 5-6 cm long by 5:3.6-4 cm wide for the forehooves and 6 cm long by 5.7-6 cm wide for the hindhooves. The tracks were widest across the middle.

Habitat. Saolas inhabit damp evergreen forests of the Annamite Mountains, possibly up to 1200 m. The species’ lower elevational limit in the absence of human disturbance is not known, but could be 200 m. Most records today are from 500-800 m.

Food and Feeding. Probably a browser, of both ground vegetation and the leaves of understory woody plants. Local people report that Saolas readily feed on the leaves of an aroid in the genus Schismatoglottis.

Breeding. Birth of a single calf in Laos in the late dry or early rainy season (i.e. April— June) is known to occur (confirmed from a fetus found in a deceased captive), and may be the norm. Otherlife history parameters (e.g. age at first breeding) are little known.

Activity patterns. Limited camera-trapping results and observations of a captive indicate that the species is diurnal and/or crepuscular.

Movements, Home range and Social organization. Seasonal movements have been reported by local people, but little more is known. Local people also report that Saolas are usually solitary, except females with calves and possibly loose, extended associations of males and females (2-3 animals) during the breeding season. Home range size is unknown.

Status and Conservation. CITES Appendix I. Classified as Critically Endangered on The IUCN Red List. There are no Saolas in captivity anywhere in the world, and no biologist has ever reported seeing one in the wild. The species became known to science only in 1992—it was one of the most spectacular zoological discoveries of the 20" century. The global population is not known, but is probably no more than a few hundred at most, and could be substantially less—the animalis so difficult to detect (solitary, shy, at low density in thick, remote forest) that a population estimate of any confidence is not possible. Surviving animals are probably fragmented into several subpopulations in Laos and Vietnam. The most recent confirmed record of the species was an animal captured by villagers in Bolikhamsay Province, Laos, in August, 2010, and photographed shortly before it died. This was the first indisputable record of a live Saola since 1999. The species is threatened mainly by hunting and snaring for animals valued in the traditional East Asian medicine and the local bushmeat trades. Saolas themselves apparently have limited value and are not aggressively sought; a greater problem is the killing of Saolas incidentally or opportunistically in the widespread pursuit of other species. The Saola is particularly susceptible to hunting with dogs, since it commonly responds to pursuit by dogs by coming to bay and making a stand in a shallow stream. Other increasing direct or indirect threats are road construction, logging, commercial agriculture, mineral mining, hydropower dam development, and human population growth. Conservation priorities are: reduction of wildlife trade demand in China, Vietnam, and Laos; immediately improved protected area management, and especially reduction of snaring and other hunting; reduction of illegal or otherwise poorly managed forest clearance; research to learn more about local human hunting patterns and also about Saola ecology, distribution, population,life history, and behavior; and providing motivation and support for Saola conservation in Laos, Vietnam, and in the international community. There may be no other mammal in Asia that shares the Saola’s combination of phylogenetic distinctiveness, degree of endangerment, and paucity of conservation attention. Despite this, there may be new hope for the Saola’s survival with the establishment of a dedicated nature reserve in Quang Nam, Vietnam.

Bibliography. Anonymous (2006), Evans et al. (2000), Gatesy & Arctander (2000), Hardcastle et al. (2004), Hassanin & Douzery (1999), Henshaw (1997), Keatts & McWilliam (2010), Kemp et al. (1995), Robichaud, W.G. (1998, 1999), Saola Working Group (2009), Schaller & Rabinowitz (1995), Thomas (1994), Timmins (2001), Timmins, Robichaud et al. (2008), Vu Van Dung, Nguyen Ngoc Chinh et al. (1995), Vu Van Dung, Pham Mong Giao, Nguyen Ngoc Chinh, Do Touc & MacKinnon (1994), Vu Van Dung, Pham Mong Giao, Nguyen Ngoc Chinh, Do Touc, Arctander & MacKinnon (1993).

Figures

1. Gaur (Bos gaurus), 2. Banteng (Bos javanicus), 3. Kouprey (Bos sauveli)

Distribution. Annamite Mts of Laos and Vietnam .