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Explanation: The
Himalayas contain the greatest diversity of wild goats and sheep (subfamily
Caprinae) in the world; ibex, tahr, argali, markhor, urial and several others
inhabit the slopes of the world's highest mountains from Afghanistan to
China. Many of these species are uncommon and local, either due to
narrow habitat niches or geographic isolation.
Not so the bharal or "blue
sheep"!
These hardy animals are the most
common and widespread of their tribe, occurring in good numbers in Pakistan,
India, Nepal, Bhutan and China, and are the most likely species to be
encountered by trekker s and other mountain travelers.
Female bharal surmounting the incredibly steep Himalayan slopes.
The classification of bharal (Pseudois
nayaur) has always been a source of debate among biologists. Its body is
similar to mountain sheep but its behavior and horns are more typical of
goats. Most biologists believe that the bharal is actually a goat that
has developed sheep-like characteristics due to the steep alpine meadow
habitat that it inhabits, and recent molecular evidence supports this
conclusion.
Like many mountain species, bharal
occur at high elevations in the summer, ranging as high as 20,000 feet (6,096
meters) where they feed on lush, green grass and other alpine plants. In
the winter, snow forces them down closer to the river valleys where they
survive on dried grass, shrubs, and roots.
The cold, very dry winter air
induces bharal to travel down to streams to drink regularly. This is
where they may encounter their main predator, the snow leopard. Tibetan wolves
also prey on bharal, especially when they wander away from escape cover such
as cliffs and rock outcrops.
Juvenile bharal, navigating steep mountain cliff faces with ease.
Although they are relatively
common and secure throughout their range, bharal face increasing threats to
their survival. Perhaps the greatest challenge is competition with
domestic livestock such as yaks, sheep and goats. Large number of
pashmina goats (which produce the high-quality pashmina wool used in scarves
and shawls) are now grazed in places such as Ladakh, India, and compete
directly with bharal and other native mountain ungulates for forage.
Poaching is also a localized threat to bharal populations.
And as bharal go, so go the snow
leopards, the wolves, and other predator species that depend on the
"goat-sheep" of the Himalayas.
Typical herd of pashmina goats, returning downslope to a
river valley after grazing in bharal habitat.
These domesticated goats
now compete with bharals and
other wild ungulates for
space and forage.
Information:
Menon, Vivek. 2003. A
Field Guide to Indian Mammals. Dorling Kindersley Pvt. Ltd. 201 pp.
Mishra, C., S.E. Van Wieren, P. Ketner, I.M.A.
Heitkönig, H.H.T. Prins. 2004. Competition between domestic
livestock and wild bharal Pseudois nayaur in the Indian
Trans-Himalaya. Journal of Applied Ecology 41(2):344-354.
Schaller, George. 1980.
Stones of Silence. Viking Press, New York, N.Y. 292 pp.
Smith,
Andrew T. and Yan Xie, editors. 2008. A Guide to the Mammals of China.
Princeton University Press. 544 pp.
Suryawanshi, K.R., Y.V. Bhatnagar, C. Mishra.
2010. Why should a grazer browse? Livestock impact on winter resource
use by bharal Pseudois nayaur. Oecologia 162(2):453-462.
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