2008/9 Schools Wikipedia Selection. Related subjects: Mammals
- This article is about the quadruped animal Gaur.
A bull Gaur at Bandipur National Park, South India
The Gaur (pronounced /ˈɡaʊɚ/) (Bos gaurus, previously Bibos gauris) is a large, dark-coated bovine animal of South Asia and Southeast Asia. The biggest populations are found today in India. It is also called seladang or in context with safari tourism Indian bison, although this is technically incorrect. The gaur is the largest species of wild cattle, bigger even than the Cape Buffalo, water buffalo and Bison. The domesticated form of the gaur is called gayal or mithun.
- Bos gaurus laosiensis (Myanmar to China), the South-east Asian gaur, sometimes also known as Bos gaurus readei. This is the most endangered gaur subspecies. Nowadays, it is found mainly in Indochina and Thailand. The population in Myanmar has been wiped out almost entirely. Southeast Asian gaurs are now found mainly in small populations in scattered forests in the region. Many of these populations are too small to be genetically viable; moreover, they are isolated from each other due to habitat fragmentation. Together with illegal poaching, this will likely put an end to this subspecies in the not so distant future. Currently the last strongholds of these giants, which contain viable populations for long-term survival are Xishuangbanna National Nature Reserve in southern Yunnan, China, Cat Tien National Park in VietNam, and Virachey national park in Cambodia. These forests, however, are under heavy pressure, suffering from the same poaching and illegal logging epidemic common in all other forests in South-east Asia.
- Bos gaurus gaurus (India, Nepal) also called "Indian bison". This is the most populous subspecies, containing more than 90 percent of the entire gaur population in the world.
- Bos gaurus hubbacki (Thailand, Malaysia). Found in southern Thailand and Malaysia peninsular, is the smallest subspecies of gaur.
- Bos gaurus frontalis, domestic gaur, probably a gaur-cattle hybrid breed
The wild group and the domesticated group are sometimes considered separate species, with the wild gaur called Bibos gauris or Bos gaurus, and the domesticated gayal or mithun (mithan) called Bos frontalis Lambert, 1804.
When wild Bos gaurus and the domestic Bos frontalis are considered to belong to the same species the older name Bos frontalis is used, according to the rules of the International Commission on Zoological Nomenclature (ICZN). However, in 2003, the ICZN "conserved the usage of 17 specific names based on wild species, which are pre-dated by or contemporary with those based on domestic forms", confirming Bos gaurus for the Gaur.
Previously thought to be closer to bison, genetic analysis has found that they are closer to cattle with which they can produce fertile hybrids. They are thought to be most closely related to banteng and said to produce fertile hybrids.
Gaur are said to look like the front of a water buffalo with the back of a domestic cow. They are the heaviest and most powerful of all wild cattle. Males have a highly muscular body, with a distinctive dorsal ridge and a large dewlap, forming a very powerful appearance. Females are substantially smaller, and their dorsal ridge and dewlaps are less developed.
- Body Length: 250-360 cm / 8.3-12 ft.
- Shoulder Height: 170-220 cm / 5.6-7.2 ft. On average, males stand about 1.8 - 1.9 m at the shoulder, females about 20cm less.
- Tail Length: 70-100 cm / 28-40 in.
- Weight: Males often 1000 - 1500 kg / 2200 - 3300 lb, females 700 - 1000 kg / 1540 - 2200 lb. Weight vary between subspecies. Among the 3 subspecies, the South-east Asian gaur is the largest, and the Malayan gaur, or seladang, is the smallest. The male Indian gaurs average 1300 kg, and large individuals may exceed 1700 kg, or 1.7 tons; whereas a Malayan gaur usually weigh 1000 - 1300 kg. The largest of all gaur, the southeast Asian gaur, weigh about 1500 kg (1.5 tons) for an average male.
Gaurs are huge animals, they are the only wild bovids to exceed a shoulder height of 2m. Size varies by region. The northern Indian gaurs do not differ in size from the southern breed; but, due to the largest concentration of gaur in the south, more of the larger, better specimens can be seen here than anywhere else in the country. The dark brown coat is short and dense, while the lower legs are white to tan in colour. There is a dewlap under the chin which extends between the front legs. There is a shoulder hump, especially pronounced in adult males. The horns are found in both sexes, and grow from the sides of the head, curving upwards. Yellow at the base and turning black at the tips, they grow to a length of 80 cm / 32 inches. A bulging grey-tan ridge connects the horns on the forehead.
The horns are flattened to a greater or less degree from front to back, more especially at their bases, where they present an elliptical cross-section; this characteristic being more strongly marked in the bulls than in the cows. The tail is shorter than in the typical oxen, and reaches but little if at all below the hocks. A third feature is presented by the distinct ridge running from the shoulders to the middle of the back, where it ends in an abrupt drop, which may be as much as five inches in height. This ridge is caused by the great height of the spines of the vertebrae of the fore part of the trunk as compared with those of the loins; but it is a characteristic much less developed in the bantering than in either of the other two species. The three species have also a characteristic colouration, the adult males being dark brown or nearly black, the females and young males being either paler or reddish brown, while in both sexes the legs from above the knees and hocks to the hoofs are white or whitish. The hair is short, fine, and glossy, and the hoofs are narrow and pointed.
The gaur is easily recognized by the high convex ridge on the forehead between the horns, which bends forward, and thus causes a deep hollow in the profile of the upper part of the head. The ridge on the back is very strongly marked, and there is no distinct dewlap on the throat and chest. The flattening of the horns at the base is very decided, and the horns are regularly curved throughout their length, and are bent inward and slightly backward at their tips. The ears are very large, the tail only just reaches the hocks, and in old bulls the hair becomes very thin on the back.
In colour the adult male gaur is dark brown, approaching black in very old individuals; the upper part of the head, from above the eyes to the nape of the neck, is, however, ashy gray, or occasionally dirty white; the muzzle is pale coloured, and the lower part of the legs pure white. The cows and young bulls are paler, and in some instances have a rufous tinge, which is most marked in individuals inhabiting dry and open districts. The colour of the horns is some shade of pale green or yellow throughout the greater part of their length, but the tips are black.
Life history and reproduction
- Gestation period: 275 days.
- Young per birth: 1, rarely 2
- Weaning: 7-12 months.
- Sexual maturity: In the 2nd and 3rd year.
- Life span: About 30 years.
- Breeding takes place throughout the year, though there is a peak between December and June.
Ecology and behaviour
In the wild, gaurs live in small herds of up to 40 individuals and graze on grasses, shoots and fruits. Where gaurs have not been disturbed, they are basically diurnal, being most active in the morning and late afternoon and resting during the hottest time of the day. But where populations have been disturbed by human populations, gaurs have become largely nocturnal, rarely seen in the open after 8:00 in the morning. During the dry season, herds congregate and remain in small areas, dispersing into the hills with the arrival of the monsoon. While gaurs depend on water for drinking, they do not seem to bathe or wallow.
Due to their formidable size and power, the gaur has few natural enemies. Crocodiles, leopards, and dhole packs occasionally attack unguarded calves or unhealthy animals, but only the tiger has been reported to kill a full-grown adult. One of the largest bull gaur seen by George Schaller during the year 1964 in Kanha national park was killed by a pack of tigers. On the other hand, there are several cases of tigers being killed by gaur. In one instance, a tiger was repeatedly gored and trampled to death by a gaur during a prolonged battle. In another case, a large male tiger carcass was found beside a small broken tree in Nagarahole national park, being fatally struck against the tree by a large bull gaur a few days earlier. When confronted by a tiger, the adult members of a gaur herd often form a circle surrounding the vulnerable young and calves, shielding them from the big cat. A herd of gaur in Malaysia encircled a calf killed by a tiger and prevented it from approaching the carcass; while in Nagarahole, upon sensing a stalking tiger, a herd of gaur walked as a menacing phalanx towards it, forcing the tiger to retreat and abandon the hunt. Gaurs are not as aggressive toward humans as Wild Asian Water Buffaloes.
A family group consists of small mixed herds of 2-40 individuals. Gaur herds are led by an old adult female (the matriarch). Adult males may be solitary. During the peak of the breeding season, unattached males wander widely in search of receptive females. No serious fighting between males has been recorded, with size being the major factor in determining dominance. Males make a mating call of clear, resonant tones which may carry for more than 1.6 kilometres. Gaurs have also been known to make a whistling snort as an alarm call, and a low, cow-like moo.
The average population density is about 0.6 animals per square kilometre, with herds having home ranges of around 80 square kilometres.
The gaur belongs to the wild oxen family, which includes wild water buffaloes. In some regions in India where human disturbance is minor, the gaur is very timid and shy, and often shuns humans. When alarmed, gaurs crash into the jungle at a surprising speed. However, in South-east Asia and south India, where they are used to the presence of humans, gaurs are said by locals to be very bold and aggressive. They are frequently known to go down fields and graze alongside domestic cattle, sometimes killing them in fights. Gaur bulls may charge unprovoked, especially during summer time when the heat and parasitic insects make them more short-tempered than usual. To warn other members of its herd of approaching danger, the gaur lets out a high whistle for help.
Tropical Asian woodlands interspread with clearings in the following countries: Bangladesh, Bhutan, Cambodia, China, India, Laos, Malaysia (Peninsular Malaysia), Myanmar, Nepal, Thailand, Viet Nam (IUCN, 2002).
At 7:30 PM on Monday, 8 January 2001, the first successful birth of a cloned animal that is a member of an endangered species occurred, a gaur named Noah at Trans Ova Genetics in Sioux Centre Iowa. He was carried and brought successfully by a surrogate mother from another, more common, species, in this case a domestic cow named Bessie. The biotechnology company Advanced Cell Technology was the first to succeed. While healthy at birth, Noah died within 48 hours of a common dysentery, likely unrelated to cloning.