Saola

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Saola
Pseudoryx nghetinhensis, b.PNG
CITES Appendix I (CITES) [1]
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Bovidae
Subfamily: Bovinae
Tribe: Bovini
Genus: Pseudoryx
Dung, Giao, Chinh, Tuoc, Arctander and MacKinnon, 1993
Species:
P. nghetinhensis
Binomial name
Pseudoryx nghetinhensis
Dung, Giao, Chinh, Tuoc, Arctander, MacKinnon, 1993
Pseudoryx nghetinhensis distribution.png
Range in Vietnam and Laos

The saola (Pseudoryx nghetinhensis), also called spindlehorn, Asian unicorn, or infrequently, Vu Quang bovid, is one of the world's rarest large mammals, a forest-dwelling bovine native to the Annamite Range in Vietnam and Laos. It was described in 1993 following a discovery of remains in Vũ Quang Nature Reserve by a joint survey of the Vietnamese Ministry of Forestry and the World Wide Fund for Nature. [2] [3] [4] Saolas have since been kept in captivity multiple times, although only for short periods as they died within a matter of weeks to months. [5] The species was first reported in 1992 by Do Tuoc, a forest ecologist, and his associates [6] and a living wild saola was first photographed in 1993 in captivity, and last photographed in 2013 by a movement-triggered camera in the forest. [7] [8]

Contents

Taxonomy

Some of the first known remains of this species, Zoological Museum of Copenhagen Saola skin.jpg
Some of the first known remains of this species, Zoological Museum of Copenhagen

In May 1992, the Ministry of Forestry, Vietnam sent a survey team to examine the biodiversity of the newly established Vu Quang National Park. On this team were Do Tuoc, Le Van Cham and Vu Van Dung (of the Forest Inventory and Planning Institute); Nguyen Van Sang (of the Institute of Ecological and Biological Resources); Nguyen Thai Tu (of Vinh University); and John MacKinnon (of the World Wildlife Fund). On 21 May, the team procured a skull featuring a pair of strange, long and pointed horns from a local hunter. They came across a similar pair in the Annamite Range in the northeastern region of the reserve the following day. The team ascribed these features to a new bovid species, calling it the "saola" or the "Vu Quang ox" to avoid confusion with the sympatric serow. The WWF officially announced the discovery of the new species on 17 July 1992. [9]

According to biodiversity specialist Tony Whitten, though Vietnam boasts a variety of flora and fauna, many of which have been recently described, the discovery of as large an animal as the saola was quite unexpected. The saola was the first large mammal to be discovered in the area for 50 years. [10] Observations of live saola have been few and far between, restricted to the Annamite Range. [11]

The scientific name of the saola is Pseudoryx nghetinhensis. It is the sole member of the genus Pseudoryx and is classified under the family Bovidae. The species was first described in 1993 by Vu Van Dung, Do Tuoc, biologists Pham Mong Giao and Nguyen Ngoc Chinh, Peter Arctander of the University of Copenhagen and John MacKinnon. [2] The discovery of saola remains in 1992 generated huge scientific interest due to the animal's special physical traits. The saola differs significantly from all other bovid genera in appearance and morphology, enough to place it in its own genus (Pseudoryx).

A recent sequencing study of ribosomal mitochondrial DNA of a large taxon sample divides the bovid family into two major subfamilial clades. The first clade is the subfamily Bovinae consisting of three tribes: Bovini (cattle and buffaloes, including the saola), Tragelaphini (Strepsicerotini) (African spiral-horned bovids) and Boselaphini (the nilgai and four-horned antelope). The second clade is the subfamily Antelopinae, which includes all other bovids. Antelopinae is composed of the three tribes: Caprini (goats, sheep, and muskox), Hippotragini (horse-like antelopes), and Antilopini (gazelles).

Since its physical traits are so complex to classify, Pseudoryx had been classified variously as member of the subfamily Caprinae and as belonging to any of the three tribes of the subfamily Bovinae: Boselaphini, Bovini and Tragelaphini. DNA analysis has led scientists to place the saola as a member of the tribe Bovini. [12] The morphology of its horns, teeth and some other features indicate it should be grouped with less-derived or more ancestral bovids. [13] Scientific consensus may lead to classifying the saola as the sole member of a proposed new tribe, Pseudorygini.

Etymology

The name 'saola' has been translated as "spindle[-horned]", although the precise meaning is actually "spinning-wheel post horn". The name comes from a Tai language of Vietnam. [14] The meaning is the same in Lao language (ເສົາຫລາ, also spelled ເສົາຫຼາ /sǎo-lǎː/ in Lao). The specific name nghetinhensis refers to the two Vietnamese provinces of Nghệ An and Hà Tĩnh, while Pseudoryx acknowledges the animal's similarities with the Arabian or African oryx. The Hmong people in Laos refer to the animal as saht-supahp, a term derived from Lao (ສັດສຸພາບ /sàt supʰáːp/) meaning "the polite animal", because it moves quietly through the forest. Other names used by minority groups in the saola's range are lagiang (Van Kieu), a ngao (Ta Oi) and xoong xor (Katu) [10] In the press, saolas have been referred to as "Asian unicorns", [11] an appellation apparently due to its rarity and reported gentle nature, and perhaps because both the saola and the oryx have been linked with the unicorn. No known link exists with the Western unicorn myth or the "Chinese unicorn", the qilin.[ verification needed ]

Description

Horns in the University of Copenhagen Zoological Museum Saola horns.jpg
Horns in the University of Copenhagen Zoological Museum

In a 1998 publication, William G. Robichaud, the coordinator of the Saola Working Group, recorded physical measurements for a captive female saola he dubbed 'Martha', [15] in a Laotian menagerie. The animal was observed for around 15 days, until she died from unknown causes. Robichaud noted the height of the female as 84 centimetres (33 in) at the shoulder; the back was slightly elevated, nearly 12 centimetres (4.7 in) taller than the shoulder height. The head-and-body length was recorded as 150 centimetres (4.9 ft). [16] The general characteristics of the saola, as shown by studies during 1993–5 as well as the 1998 study, include a chocolate brown coat with patches of white on the face, throat and the sides of the neck, a paler shade of brown on the neck and the belly, a black dorsal stripe, and a pair of nearly parallel horns, present on both sexes. [2] [16] [17]

Robichaud noted that the hair, straight and 1.5–2.5 centimetres (0.59–0.98 in) long, was soft and thin–a feature unusual for an animal that is associated with montane habitats in at least a few parts of its range. While the hair was found to be short on the head and the neck, it thickened to woolly hair on the insides of the forelegs and the belly. Studies before 1998 reported a hint of red in the inspected skins. The neck and the belly are a paler shade of brown compared to the rest of the body. A common observation in all the three aforementioned studies is a 0.5 centimetres (0.20 in) thick stripe extending from the shoulders to the tail along the middle of the back. The tail, which measured 23 centimetres (9.1 in) in Robichaud's specimen, is divided into three horizontal bands, brown at the base, black at the tip and white in the middle. [2] [16] [17] Saola skin is 1–2 millimetres (0.039–0.079 in) thick over most of the body, but thickens to 5 millimetres (0.20 in) near the nape of the neck and at the upper shoulders. This adaptation is thought to protect against both predators and rivals' horns during fights. [18]

Skull fragments, also in the University of Copenhagen Zoological Museum Saola skull.jpg
Skull fragments, also in the University of Copenhagen Zoological Museum

The saola has round pupils with dark-brown irises that appear orange when light is shone into them; a cluster of white whiskers about 2 centimetres (0.79 in) long with a presumably tactile function protrude from the end of the chin. The specimen Robichaud observed could extend its tongue up to 16 centimetres (6.3 in) and reach its eyes and upper parts of the face; the upper surface of the tongue is covered with fine, backward-pointing barbs. Robichaud observed that either of the two maxillary glands (sinuses) had a nearly rectangular hollow with the dimensions 9×3.5×1.5 centimetres (3.54×1.38×0.59 in), covered by a 0.8 centimetres (0.31 in) thick flap. The maxillary glands of the saola are probably the largest among those of all other animals. The glands are covered by a thick, pungent, grayish green, semi-solid secretion beneath which lies a sheath of few flat hairs. Robichaud observed several pores, used probably for secretion, on the upper surface of the lid. Each white facial spot shelters one or more nodules from which originate 2–2.5 centimetres (0.79–0.98 in) long white or black hairs. These secretions are typically rubbed against the underside of vegetation, leaving a musky, pungent paste. The spoor of the forelegs measured 5–6 centimetres (2.0–2.4 in) long by 5.3–6.4 centimetres (2.1–2.5 in) wide, and 6 centimetres (2.4 in) long by 5.7–6 centimetres (2.2–2.4 in) for the hindlegs. [16]

Both sexes possess slightly divergent horns that are similar in appearance and form almost the same angle with the skull, but differ in their lengths. Horns resemble the parallel wooden posts locally used to support a spinning wheel (thus the familiar name "spindlehorn"). [4] These are generally dark-brown or black and about 35–50 cm long; twice the length of their head. [16] Studies in 1993 and 1995 gave the maximum distance between the horn tips of wild specimens as 20 centimetres (7.9 in), [2] [17] but the female observed by Robichaud showed a divergence of 25 centimetres (9.8 in) between the tips. Robichaud noted that the horns were 7.5 centimetres (3.0 in) apart at the base. While studies prior to Robichaud's claim the horns are uniformly circular in cross-section, Robichaud observed his specimen had horns with a nearly oval cross-section. The sides of the base of the horns is rugged and indented. [16]

Habitat and distribution

Saola inhabit wet evergreen or deciduous forests in eastern Southeast Asia, preferring river valleys. Sightings have been reported from steep river valleys at 300–1800 m above sea level. In Vietnam and Laos, their range appears to cover approximately 5000 km2, including four nature reserves. During the winters, saola tend to migrate down to the lowlands. [19]

Ecology and behaviour

Hooves in the University of Copenhagen Zoological Museum Saola hooves.jpg
Hooves in the University of Copenhagen Zoological Museum

Local people reported that the saola is active in the day as well as at night, but prefers resting during the hot midday hours. Robichaud noted that the captive female was active mainly during the day, but pointed out that the observation could have been influenced by the unfamiliar surroundings the animal found herself in. When she rested, she would draw her forelegs inward to her belly, extend her neck so that her chin touched the ground, and close her eyes. [16] Though apparently solitary, saola have been reported in groups of two or three [2] as well as up to six or seven. Grouping patterns of the saola resemble those of the bushbuck, anoa, and sitatunga. [17]

Robichaud observed that the captive female was calm in the presence of humans, but was afraid of dogs. On an encounter with a dog, she would resort to snorting and thrust her head forward, pointing her horns at her opponent. Her erect ears pointed backward, and she stood stiffly with her back arched. Meanwhile, she hardly paid any attention to her surroundings. This female was found to urinate and defecate separately, dropping her hind legs and lowering her lower body – a common observation among bovids. She would spend considerable time grooming herself with her strong tongue. Marking behaviour in the female involved opening up the flap of the maxillary gland and leaving a pungent secretion on rocks and vegetation. She would give out short bleats occasionally. [16]

Diet

Robichaud offered spleenwort (Asplenium), Homalomena , and various species of broad-leaved shrubs or trees of the family Sterculiaceae to the captive animal. The saola fed on all plants, and showed a preference for the Sterculiaceae species. She did not pull at leaves, she would rather chew or pull them into her mouth using her long tongue. She fed mainly during the day, and rarely in the dark. [16] The saola is also reputed to feed on Schismatoglottis , unlike other herbivores in its range. [20]

Reproduction

Very little information is available about the reproductive cycle of the saola. The saola is likely to have a fixed mating season, from late August to mid-November; only single calf births have been documented, mainly during summer between mid-April and late June. [16] [18] In the absence of more specific data, the gestation period has been estimated as similar to that of Tragelaphus species, about 33 weeks. [16] Three reports of saola killings from nearby villagers involved young accompanying mothers. One possessed 9.5 cm (3.7 in) long horns, another an estimated 15 cm (5.9 in), and the third 18.8 cm (7.4 in); these varying horn lengths suggest a birth season extending over at least two to three months. [17]

Conservation

The saola is currently considered to be critically endangered. [1] Its restrictive habitat requirements and aversion to human proximity are likely to endanger it through habitat loss and habitat fragmentation. Saola suffer losses through local hunting and the illegal trade in furs, traditional medicines, and for use of the meat in restaurants and food markets. [21] They also sometimes get caught in snares that have been set to catch animals raiding crops, such as wild boar, sambar, and muntjac. More than 26,651 snares have so far been removed from Saola habitats by conservation groups. [22]

The key feature of the area occupied by the saola is its remoteness from human disturbance. [23] Saola are shot for their meat, but hunters also gain high esteem in the village for the production of a carcass. Due to the scarcity, the locals place much more value on the saola than more common species. Because the people in this area are traditional hunters, their attitude about killing the saola is hard to change; this makes conservation difficult. The intense interest from the scientific community has actually motivated hunters to capture live specimens. Commercial logging has been stopped in the nature reserve area of Bu Huong, and there is an official ban on forest clearance within the boundaries of the reserve. [23]

Species of conservation concern are frequently hard to study; there are often delays in implementing or identifying necessary conservation needs due to lack of data. [24] Because the species is so rare, there is a continuous lack of adequate data; this is one of the major problems facing saola conservation. Trained scientists have never observed saola in the wild. Unfortunately, because it is unlikely that intact saola populations exist, field surveys to discover these populations are not a conservation priority. [24]

The Saola Working Group was formed by the IUCN Species Survival Commission's Asian Wild Cattle Specialist Group, in 2006 [25] to protect the saolas and their habitat. This coalition includes about 40 experts from the forestry departments of Laos and Vietnam, Vietnam's Institute of Ecology and Biological Resources, Vinh University, biologists and conservationists from Wildlife Conservation Society, and the World Wide Fund for Nature. [26]

A group of scientists from the Vietnam Academy of Science and Technology in central Hanoi, within the Institute of Biotechnology, investigated a last resort effort of conserving the species by cloning, an extremely difficult approach even in the case of well-understood species. [4] However, the lack of female saola donors of enucleated ovocytes and receptive females, as well as the interspecific barriers, greatly compromise the potential success of the cloning technique. [27]

See also

Related Research Articles

Bovinae Subfamily of mammals

Bovines comprise a diverse group of 10 genera of medium to large-sized ungulates, including domestic cattle, bison, African buffalo, water buffalos, and the four-horned and spiral-horned antelopes. The evolutionary relationship between the members of the group is still debated, and their classification into loose tribes rather than formal subgroups reflects this uncertainty. General characteristics include cloven hooves and usually at least one of the sexes of a species having true horns. The largest extant bovine is the gaur.

Giant muntjac Species of deer

The giant muntjac,, sometimes referred to as the large-antlered muntjac, is a species of muntjac deer. It is the largest muntjac species and was discovered in 1994 in Vũ Quang, Hà Tĩnh Province of Vietnam and in central Laos. During inundation of the Nakai Reservoir in Khammouane Province of Laos for the Nam Theun 2 Multi-Purpose Project, 38 giant muntjac were captured, studied, and released into the adjacent Nakai-Nam Theun National Protected Area. Subsequent radio-tracking of a sample of these animals showed the relocation was successful. The species is also located in parts of eastern Cambodia, as well as the Trường Sơn Mountains.

Four-horned antelope Small antelope from Asia (Tetracerus quadricornis)

The four-horned antelope, or chousingha, is a small antelope found in India and Nepal. Its four horns distinguish it from most other bovids, which have two horns. The sole member of the genus Tetracerus, the species was first described by French zoologist Henri Marie Ducrotay de Blainville in 1816. Three subspecies are recognised. The four-horned antelope stands nearly 55–64 centimetres (22–25 in) at the shoulder and weighs nearly 17–22 kilograms (37–49 lb). Slender with thin legs and a short tail, the four-horned antelope has a yellowish brown to reddish coat. One pair of horns is located between the ears, and the other on the forehead. The posterior horns are always longer than the anterior horns, which might be mere fur-covered studs. While the posterior horns measure 8–12 centimetres (3.1–4.7 in), the anterior ones are 2–5 centimetres (0.79–1.97 in) long.

Scimitar oryx Species of oryx

The scimitar oryx, also known as the scimitar-horned oryx and the Sahara oryx, is a species of Oryx that was once widespread across North Africa. The species went extinct in the wild in 2000, but a group was released into an acclimation enclosure within the Ouadi Rimé-Ouadi Achim Faunal Reserve in 2016, then reintroduced back into the wild. An additional 21 animals were placed in the acclimation enclosure in 2017. In 2000, the species was declared extinct in the wild by the International Union for the Conservation of Nature (IUCN). The first ones to be relocated were released into the wild in 2016 and have adapted well to their surroundings. In 2017, another herd of 75 scimitar-horned oryxes arrived in an operation led by Chad's Ministry of Environment and Fisheries and the Sahara Conservation Fund. In 2021, 60 new calves were born, bringing the number in the wild to about 400. The species has not been assessed by the IUCN, though, since 2016, when the species was truly extinct in the wild, so it remains as extinct in the wild (EW). This particular oryx can survive for months or even years without drinking water. A grazing animal, it derives most of its daily moisture intake from plants.

Indian muntjac Barking deer (Muntiacus muntjak)

The Indian muntjac, also called the southern red muntjac and barking deer, is a deer species native to South and Southeast Asia. It is listed as Least Concern on the IUCN Red List.

Annamite striped rabbit Species of mammal

The Annamite striped rabbit is a species of rabbit native to the Annamite mountain range on the Laos-Vietnam border. The rabbit is striped, with a red rump, and resembles the Sumatran striped rabbit. It only recently became known to Western scientists: striped rabbits were first observed in 1996 by biologist Rob Timmins in a market in Bak Lak in Laos, and the species was described in 2000 and named after Timmins' find.

The Gilled Antelope, claimed under the classification of "Cetaformia anthalopus", is a false species. This species was rumored to be either an antelope or deer which had the capability to breathe underwater by use of a set of gills on its muzzle. Reports claiming the creature to be real state that the rare sightings occur in Cambodia.

Indo-Burma

Indo-Burma is a biodiversity hotspot designated by Conservation International.

Wildlife of Laos

The wildlife of Laos encompasses the animals and plants found in the Lao People's Democratic Republic, a landlocked country in southeastern Asia. Part of the country is mountainous and much of it is still clad in tropical broadleaf forest. It has a great variety of animal and plant species.

Pù Mát National Park National park in Vietnam

Pù Mát National Park is a national park in Nghệ An Province, in Vietnam's North Central Coast region. It is part of the Western Nghệ An Biosphere Reserve.

Bovini Tribe of cattle

The tribe Bovini, or wild cattle are medium to massive bovines that are native to North America, Eurasia, and Africa. These include the enigmatic, antelope-like saola, the African and Asiatic buffalos, and a clade that consists of bison and the wild cattle of the genus Bos. Not only are they the largest members of the subfamily Bovinae, they are the largest species of their family Bovidae. The largest species is the gaur, weighing up to 1,500 kg (3,300 lb).

Nakai-Nam Theun National Park in Nakai District, Khammouane Province, Laos, is one of the last remaining wildernesses in Southeast Asia. Nakai-Nam Theun covers approximately 4,270 km2 of the Annamite Range and the adjacent Nakai Plateau in Khammouane and Bolikhamsai Provinces. It was designated a national park on 15 February 2019 by Prime Ministerial Decree No. 36, 15 February 2019. It is managed by the Ministry of Agriculture and Forestry (MAF). It is adjacent to the Vu Quang National Park of Vietnam.

Vũ Quang National Park

Vũ Quang National Park is a national park in Vũ Quang District, Hà Tĩnh Province, North Central Coast, Vietnam. This park contains biodiversity. Saola and Giant muntjac are species found in this park. Vũ Quang is a remote forested region of Vietnam, in which several new species of deer and antelope have been discovered since the 1990s. Some are so new that scientific description is still pending, although most have local names.

The Phou Hin Poun National Biodiversity Conservation Area, formerly known as the Khammouane Limestone National Biodiversity Conservation Area, is one of 21 National Biodiversity Conservation Areas of the Lao People's Democratic Republic. Located in a limestone tower karst region of the Annamite Range in Khammouane Province, it is home to a number of rare or newly discovered species. National Biodiversity Conservation Areas are not protected by the government of Laos in any meaningful way; the budget for each is about $500. The human population of the NBCA is 29,603.

Saola Working Group

The Saola Working GroupSWG is a working group of the IUCN Species Survival Commission's Asian Wild Cattle Specialist Group, created in 2006 to protect the saolas and their habitat. The Conservancy works to engage and incorporate local communities in protecting saolas in Annamite Range mountains on the border of Laos and Vietnam. The Saola is one of the most endangered species in the world. Discovered in 1992 it was the first large mammal new to science in more than 50 years and has never been seen by a biologist in the wild. The Saola Working Group is a coalition that includes about 40 experts from the forestry departments of Laos and Vietnam, Vietnam's Institute of Ecology and Biological Resources, Vinh University, biologists and conservationists from Wildlife Conservation Society and the World Wildlife Fund.

Bolikhamsai province Province of Laos

Bolikhamsai is a province of Laos. Pakxan, Thaphabat, Pakkading, Borikhane, Viengthong, and Khamkeut are its districts and Pakxan is its capital city. The province is the site of the Nam Theun 2 Dam, the country's largest hydroelectric project.

Khammouane province Province of Laos

Khammouane province (Khammouan) is a province in the center of Laos. Its capital lies at Thakhek.

Protected areas of Vietnam

Many areas of Vietnam are under protection. While the national reserves cover small areas of scientific significance with restricted access, the national parks also cover wetlands of Ramsar designated areas and BirdLife International inscribed bird areas. The largest of the national parks initially covered were the Cúc Phương National Park, the Cát Tiên National Park, and the Côn Đảo National Park which to start with were forest areas cum reserves or prohibited areas. The objective for creating national parks was to allow access to the reserved areas as a part of ecotourism and cultural needs with full attention to the basic approach of conservation of natural environmental resources.

Bubalina Subtribe of bovines consisting of the true buffalo

Bubalina is a subtribe of wild cattle that includes the various species of truebuffalo. Species include the African buffalo, the anoas, and the wild water buffalo. Currently, buffalos can be found naturally in sub-Saharan Africa, South Asia and Southeast Asia, and domestic and feral populations have been introduced to Europe, the Americas, and Australia. In addition to the living species, bubalinans have an extensive fossil record where remains have been found in much of Afro-Eurasia.

References

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Further reading