The chiru is endemic to the Tibetan Plateau. It weighs 26 -
40 kg (57 - 88 lb) and favors alpine steppe or similar semiarid habitats. The
chiru prefers flat to rolling terrain, although it readily ascends high rounded
hills and penetrates mountains and crosses passes by following valleys. It can
be found at elevations from 3250 - 5500 m (10,660 - 18,000 ft). Movement
patterns of the chiru are complex, with females following different patterns
from males.Females can migrate up to
300 km (190 mi) between winter mating grounds and summer calving grounds. Chiru
herds also vary widely in size and composition. Although herds of 15,000 are no
longer seen, as they were a century ago, herds of 1000 or more can still be
observed.
The chiru is found primarily on the alpine steppe of
northwest Tibetin China. There
are a number of both migratory as well as resident populations. The only chirus
found outside Chinaare in the Ladakh area of Indiaand comprise only about 200 animals. From Ladakh, the chiru's distribution
extends 1600 km (990 mi) eastward across Tibetand southern Xinjiang to Qinghai.
The range of the chiru from west to east appears to be much as it was a century
ago. However, the range has contracted in central Tibetand eastern Qinghai.
Poaching is the most serious threat to the chiru. It is
being slaughtered illegally by the thousands for its wool, which is known in
the international market as "shahtoosh" or "king of wool."
Tidbits
*** "Almost from my feet away to the north and east, as
far as the eye could reach, were thousands upon thousands of doe antelope with
their young...Everyone in camp turned
out to see this beautiful sight, and tried, with varying results, to estimate
the number of animals in view.This was
found very difficult however, more particularly as we could see in the extreme
distance a continuous stream of fresh herds steadily approaching: there could
not have been less than 15,000 or 20,000 visible at one time." (Rawling
1905, cited in Schaller 1998)
*** Chirus paw bowl-shaped hollows in sandy and silty soil,
roughly circular hollows 110 - 120 cm (43 - 47 in) in diameter and 15 - 30 cm
(6 - 12 in) deep. These hollows are distinctive, quite unlike the shallow scrapes
made by blue sheep and argalis on a hillside for resting, the trampled and
churned depressions created by wallowing yaks, the fan-shaped pawed sites at
gazelle latrines, or the irregular holes and trenches with their litter of
feces dug by kiang. The seasonal use of hollows, their dispersion, and the lack
of feces appear related and suggest that the hollows function primarily to
conceal chirus from oestrid flies, which probably find hosts by sight and
smell. (Schaller 1998)
*** The chiru is a remarkable runner. Despite the thin
atmosphere on the high plateau, it can run as fast as 80 km/h (50 mi/h). This
is not only because it is so light and nimble, but also because its muzzle is
particularly swollen and it has many air sacs in its nostrils, aiding its
breathing. (Tan 1996)
*** There are no known chirus in captivity (Mallon &
Kingswood 2001).
2003: Occurs in China(Qinghai, Xinjiang) and India(Ladakh/Jammu & Kashmir). May be extinct in Nepal.
(IUCN 2004)
Population Estimates:
[Note: Figures
given are for wild populations only.]
* WORLD
o 1950 - 60:
500,000 - 1,000,000 (IUCN 2000a)
o 1993:
Probably exceeds 100,000 (East 1993)
o 1998:
Perhaps fewer than 75,000 (Schaller 1998)
o 2000:
Could be as low as 65,000 - 75,000 (IUCN 2000a)
o 2001: Less
than 75,000 (Mallon & Kingswood 2001)
History of
Distribution:
The chiru is endemic to the Qinghai-Tibetan Plateau. It is
found primarily on the alpine steppe of northwest Tibetin the remote Chang Tang area of China.
There are a number of both migratory as well as resident populations. The only
chirus found outside Chinaare in the Ladakh area of India's
state of Jammu & Kashmir. At present, the chiru occurs in only two small
areas of eastern Ladakh, where about 200 animals, mostly males, cross the
border seasonally from Tibetand Xinjiang. A few once strayed into western Nepal,
but there is no evidence that they still do so. From Ladakh, the chiru's
distribution extends 1600 km (990 mi) eastward across Tibetand southern Xinjiang to Qinghai.
Its current range is divided into two areas: a northern one of about 490,000 sq
km (190,000 sq mi) and a central one of about 115,000 sq km (44,000 sq
mi).The range of the chiru from west to
east appears to be much as it was a century ago. However, the range has
contracted in central Tibetand eastern Qinghai. The great
herds of 15,000 animals or more that Western explorers reported a century ago
are now gone. (Schaller 1998)On the
other hand, recent reports indicate that the number of chirus has increased
lately due to improved enforcement by Tibetan officials against poaching (G.
Schaller, cited in Wildl. Cons. Soc. 2004).
Distribution Map (7 Kb GIF) (Huffman 2004)
Threats and Reasons
for Decline:
Poaching is the most serious threat to the chiru. It is
being slaughtered illegally by the thousands for its wool (actually, the underfur
of the chiru), which is known in the international market as
"shahtoosh" or "king of wool." Shahtoosh is considered to
be one of the finest animal fibers in the world and, since the 1980s, expensive
shahtoosh shawls and scarves have become high fashion status symbols in the
West, selling for as much as $10,000 each. Several chirus are killedto provide wool for a single shawl.
(Collection of the underfur causes the death of the chiru.) Wool is smuggled
from Tibetmainly to Kashmir in India,
where it is woven into an extremely fine fabric from which the shawls and
scarves are woven. Although the chiru is protected in China,
it is still legal to weave shahtoosh in India.
(IUCN 2000a, Oryx 2000, IUCN 2004)
Other threats to the chiru include habitat loss due to the
expansion of domestic livestock herding, fencing of rangeland, and economic
development. Their horns are also used in traditional medicine in China.
Data on Biology and Ecology
Size and Weight:
The chiru stands
83 - 100 cm (33 - 39") at the shoulder. Females weigh about 26 kg (57 lb);
males weigh about 40 kg (88 lb).
Habitat:
The chiru prefers
flat to rolling terrain, although it readily ascends high rounded hills and
penetrates mountains and crosses passes by following valleys. Alpine steppe or
similar semiarid habitats are favored, it being rare or absent from those parts
of the alpine meadow region that have an average annual precipitation of 400 mm
(16 in) or more. Desert steppe and other such arid areas have also been occupied,
at least seasonally. In some areas the chiru frequents elevations as low as
3250 m (10,660 ft), but most of its range lies above 4000 m (13,100 ft), and in
northern Ladakh it can be found as high as 5500 m (18,000 ft). (Schaller 1998)
The chiru is one
of the species that live in both the Himalaya and
Mountains of Southwest China Biodiversity Hotspots (Cons. Intl.) and the
Tibetan Plateau Steppe Global 200 Ecoregion. (Olson & Dinerstein 1998,
Olson & Dinerstein 1999)
Age to Maturity:
As with many
medium-sized ungulates, female chirus probably first conceive at the age of 1.5
or 2.5 years and give birth at the age of 2 or 3 years. (Schaller 1998)
Gestation Period:
7 - 8 months
(Nowak 1999).
Birth Season:
Female chirus give
birth in the second half of June and early July (Schaller 1998). The
approximate main mating season is in late November and December (Schaller
1977).
Birth Rate:
Females give birth
to a single young.
Dispersal:
Sometime in late
April or May, most 10- to 11-month old males separate from their mothers and
either join their male peers or associate with adult males until early winter,
when, like the adult males, many join mixed herds. Young females remain with
their mothers. (Schaller 1998)
Maximum Age:
At least about 8
years (wild) (Schaller 1998).
Diet:
The chiru is a
grazer and perhaps a browser (Nowak 1999). It feeds mainly on forbs, grasses,
and sedges (Mallon & Kingswood 2001).
Behavior:
Movement patterns
of the chiru are complex, and the movements of the two sexes must be discussed
separately. Males and females are mostly on the same winter grounds during the
rut.
* During
spring, some females remain on the winter grounds in resident populations, but
others migrate. In May and June the migratory females and their female
offspring separate from the males and travel up to 300 km (190 mi) north into
desolate and uninhabited terrain to summer calving grounds. They migrate back
to the fall and winter grounds in late July and early August.
* Males have
several movement patterns.At some point
in late April or May, most 10- to 11-month old males separate from their
mothers and either join their male peers or the adult males, which also part
from the females at that time. Some males remain on the winter grounds as
resident populations. Many males travel at least a short distance to a summer
range. Some males travel far from their winter grounds, usually northward,
dispersing widely, and then in autumn return to traditional fall and winter
grounds for the rut. As a result of these diverse movement patterns, males, in
contrast to females, tend to be scattered throughout the range of the species
during summer.
Social Organization:
Herd dynamics vary
greatly by sex and season as herds change in size and composition and animals
shift associations. As with many ungulate species, the only long-lasting
association is between a female and her young, a bond which may persist well
into the offspring’s second year. All other associations appear to be unstable,
lasting from minutes or hours to perhaps days. Three types of herds are
evident: males (yearling (age: 1 year - maturity) and adult) were often either
alone or in all-male herds; female herds consisted of only females with their
offspring; and mixed herds contained one or more animals of both sexes.
(Schaller 1998)
Average and range
of herd sizes for Qinghai in
1985, Qinghai in 1986 and
Xinjiang in 1987:
* Male herds: averaged from 5.0 - 7.4
(range 2 - 38)
However, the above
figures do not show the full range of possible female herd sizes during rapid
migratory movements. Over 7000 chirus in one population of females and newborns
included 3.2% in herds of 2-50, 8% in herds of 51-100, 26.6% in herds of
101-500, and 62.2% in herds exceeding 500, with the largest including at least
1000. (Schaller 1998)
During the mating
season, each adult male attempts to form a harem of 10 - 20 females, which it
guards jealously. If one doe attempts to leave a harem , the male tries to
drive her back. Meanwhile, the other does may use the opportunity to desert, as
there is apparently no lasting bond between the sexes. (Nowak 1999)
Age and Gender
Distribution:
Composition of
various migratory chiru populations from 1990 - 1993 (Schaller 1998):
*
Young/Females: 30.8/100 - 47.7/100 (n (number of populations) = 6), 12.2/100 (n
= 1), and 5/100 (n=1) (exceptionally low)
Between 1990 and
1993, the combined central and eastern populations in the Chang Tang region of Tibetaveraged 29% males, 53% females, and 18% young. Under normal circumstances the
ratio of young to females ranged from about 30:100 to 50:100. (Schaller 1998)
Mortality and
Survival:
Schaller concluded
that mortality of young was high, up to half dying within a month or two after
birth, and that at least 2/3 of the chirus died between birth and the age of 2
years (Schaller 1998).
Density and Range:
Densities:
* 1.47 individuals/sq
km (3.81 individuals/sq mi) (3087 chirus in 2100 sq km (810 sq mi); November
1986; Qinghai)
* 0.015
individuals/sq km (0.039 individuals/sq mi) (281 animals in 17,900 sq km (6900
sq mi); November 1986; Qinghai)
* Minimum density
of 0.11 individuals/sq km (0.28 individuals/sq mi) (438 animals in 4000 sq km
(1500 sq mi); July 1988; Xinjiang)
* 0.16
individuals/sq km (0.41 individuals/sq mi) (2946 animals in 18,000 sq km (6900
sq mi); 1988; Arjin Shan Reserve)
* 0.36
individuals/sq km (0.93 individuals/sq mi) (635 animals in 1800 sq km (690 sq
mi); August 1990; AruBasinin the Chang Tang Reserve, Tibet)
* Extensive
census in the Chang Tang, Tibet:
1991 - minimum of 0.22 individuals/sq km (0.57 individuals/sq mi) over 17,500
sq km (6800 sq mi); 1993 - 0.29 individuals/sq km (0.75 individuals/sq mi) over
10,500 sq km (4100 sq mi). These densities are probably not exceeded elsewhere
over such a large area.
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