| Gaur |
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| Bos gaurus Lambert, 1804 |
The
type locality is North-East of Chittagong in Bangladesh. Some authors
treat the wild and domestic forms of gaur as separate species Bos gaurus and Bos frontalis. The domestic gaur, also called gayal, mithan or mithun, (Bos frontalis)
is probably the result of crossbreeding with domestic cattle.
Currently, the two forms are considered synonymous, and the domestic
species is designated equally as Bos gaurus or Bos frontalis. The gaur is the member of the subgenus Bibos
(Hodgson, 1837) with the banteng and the kouprey, and it was at one
time elevated to a genus. Many subspecies of gaur have been described,
but currently only three subspecies are recognized (see below).
However, further research is required to precisely determine the
taxonomy of this species.
Once distributed all across South-East Asia, gaur populations are now fragmented and confined to isolated areas. Bos gaurus gaurus occurs in India, Southern Nepal; B. g. laosiensis ranges in Myanmar, Laos, Vietnam, Cambodia and Southern China; and B. g. hubbacki in Thailand and Malaysia. The domestic form is used in the border area of Myanmar, Manipur and Nagaland.
Adult
males can reach 170 to 220 cm tall, with a body mass ranging from 600
to 1000 kg, compared with 450 to 800 kg for the cows. The domestic gaur
or Mithan is different from the wild gaur by having shorter legs and
males have no dorsal hump. The head is also shorter and the horns grow
straight upward. Gaur subadults are chestnut with white stockinged
legs. Adult gaurs are dark brown to black with white stockinged legs,
and present large horns that curve inward near the tip. Gaurs are
sexually dimorphic. Adult males have a pronounced muscular crest
between the shoulders and a large dewlap hanging between the forelegs
and a smaller one under the chin. The male horns grow out and up and
have thick basal diameters. Females show slight muscular development of
the neck and shoulders. In females, the horns curve inward sharply with
thin basal diameters. The tip of the horn is black. Yellow hair at the
base of the horns contrasts with adult dark body colour. The gaur
produces a distinct smell which probably repels the insects.
Gaur
are found in hilly areas, below 1,800 m, covered with large tracts of
forests (dry dipterocarp forest, evergreen forest, mixed-deciduous
forest) and grasslands (Schaller, 1967). They use a large scope of
habitats and tend to spend more time in evergreen forest and in higher
elevation zones during the dry season (Prayurasiddhi, 1997). Forest
edges, riverbanks, including areas with grass growth after burning are
particularly utilised. Gaur tolerate well habitat degradation due to
human activities and in fact may benefit from limited forest
disturbance. They often forage in plantations and cultures; shifting
cultivation provides openings in the canopy and increases the
vegetation density of ground cover. They are both grazers and browsers;
they browse more than other species of wild cattle. Bamboo shoots are
one of the most frequently eaten foods in rainy season in Thailand
(Prayurasiddhi, 1997). Water availability throughout the year is
particularly important to support this species; and they generally do
not travel more than a day’s walking distance from water (Conry,
1981). They do not wallow. Mineral licks and mineral rich springs are
important requirements for this species. Home range size varies
according to the sex, the season, the locality and herd size. It varies
from 27 km2 to 137 km2 in Malaysia (Conry, 1989).
Home range size is larger during the wet season than in the dry season,
and larger herds have a larger annual home range than smaller herds.
However, daily movement does not change between wet and dry seasons,
and corresponds to about 3 km per day (Prayurasiddhi, 1997). The main
activity period occurs during the night; during the day they stay
hidden in forest or high grasses to ruminate. It is thought that such
activity pattern is largely influenced by human disturbances since
captive individuals are more diurnal. They live in herd of 3 to 40
individuals. Herd structure consists of adult males and females,
sub-adults and calves. This structure is conserved between seasons.
Individuals maintain their relative position in the herd’s
dominance hierarchy by sparring (Thomas, 1996). The oldest female leads
the herd to foraging locations and the dominant males play a defensive
role (Prayurasiddhi, 1997). Dominance rank inside the herd is
determined by individual body size (Schaller, 1967; Thomas, 1996). Gaur
herds can occasionally associate with sambar deer (Cervus unicolor).
Female are polyestrus and reproduction can occur at any time of the
year, with peaks of birth depending of environmental conditions. A
single calf is born after nine months of gestation. Maximum longevity
in captivity is 24 years (Thomas, 1996). Calf and juvenile gaurs have
several predators (Panthera tigris; Panthera pardus; Neofelis nebulosa; Cuon alpinus; Ursus thibetanus), but only tigers are powerful enough to kill adults.
The
global population of gaur is estimated to be between 13,000 and 30,000
individuals, with a dramatic decline all across its range due to
unprecedented growth of human population in South-East Asia. Decline
factors include poaching, habitat destruction, competition for food
resources and disease transmission from domestic cattle. Rinderpest has
for example dramatically affected the Indian gaur population in 1968.
Conservation and management plans for the gaur are implemented in
Malaysia and Vietnam where scattered populations are close to
extinction. B. g. laosiensis and B. g. hubbacki are
particularly endangered. There has been at least a 60% reduction in the
gaur population in Thailand in only 20 years (Srikosamatara and
Suteethorn, 1995). Poaching to sell the horns as trophies constitutes
the main cause of overexploitation of remnant populations. Subsistence
hunting has apparently a small influence on the viability of the
population of gaurs. Ex situ conservation programs are
implemented for gaur in US and in Europe. However, these captive
populations are too small and dangerously inbred. In 2001, a gaur was
cloned in U.S., but it died within a couple of days.
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