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Namgail, T., Fox, J., & Bhatnagar, Y. V. (2004). Habitat segregation between sympatric Tibetan argali Ovis ammon hodgsoni and blue sheep Pseudois nayaur in the Indian Trans-Himalaya. Journal of Zoology, 262, 57–63.
Abstract: Tibetan argali Ovis ammon hodgsoni and blue sheep Pseudois nayaur have almost completely overlapping distributions encompassing most of the Tibetan plateau and its margins. Such a sympatric distribution of related species with similar ecological requirements implies that there is some degree of resource partitioning. This may be accomplished on the basis of habitat and/or diet separation. This study evaluated such ecological separation on the basis of physical habitat partitioning by these two sympatric ungulates in Hemis High Altitude National Park, Ladakh, India, in an area where the argali established a small new population in 1978. Such separation was tested for
on the basis of expected difference between the species in their proximity to cliffs, associated with species-specific anti-predator behaviour. Tibetan argali selected habitats away from cliffs while blue sheep selected habitats close to cliffs. Blue sheep also selected steep slopes whereas argali selected gentle slopes. The two species did not differ
in their use of habitats in terms of elevation. They did, however, differ in their use of plant communities; blue sheep selected sub-shrub and grass-dominated communities whilst argali selected forb-dominated communities. We suggest that the two species coexist in this site as a result of the differential use of habitat associated with their
species-specific anti-predator strategies.
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Bhatnagar, Y. V., Mathur, V. B., & McCarthy, T. (2002). A Regional Perspective for Snow Leopard Conservation In the Indian Trans-Himalaya.. Islt: Islt.
Abstract: The Trans-Himalaya is a vast biogeographic region in the cold and arid rain-shadow of
the Greater Himalaya and is spread over three Indian states. From the conservation
standpoint this region has several unique characteristics. Unlike most other
biogeographic regions of the country, it has wildlife, including large mammals, spread
over the entire region. Another feature is that the harsh climate and topography
provides limited agricultural land and pastures, all of which are currently utilized by
people. The harsh environment has given rise to a specialized assemblage of flora and fauna in
the region that include the endangered snow leopard, a variety of wild sheep and goat,
Tibetan antelope, Tibetan gazelle, kiang and wild yak. The snow leopard is one of the
most charismatic species of the Trans-Himalaya. This apex predator, with a wide
distribution, has ecological importance and international appeal, and is eminently
suitable to be used as both a 'flagship' and an 'umbrella species' to anchor and guide
conservation efforts in the Trans-Himalayan region. Among the 10 Biogeographic Zones in the country, the Trans-Himalaya has a
comparatively large Protected Area (PA) coverage, with over 15,000 km2 (8.2 %) of
the geographical area under the network. In spite of this, the bulk of the large mammal
populations still exist outside the PAs, which include highly endangered species such
as snow leopard, chiru, wild yak, Ladakh urial, kiang and brown bear. Given the sparse resource availability in the Trans-Himalaya and the existing human
use patterns, there are few alternatives that can be provided to resource dependent
human communities in and around PAs. The existing PAs themselves pose formidable
conservation challenges and a further increase in their extent is impractical. The
problem is further compounded by the fact that some of the large PAs have unclear
boundaries and include vast stretches that do not have any direct wildlife values. These
issues call for an alternative strategy for conservation of the Trans-Himalayan tracts
based on a regional perspective, which includes reconciling conservation with
development. In this paper we stress that conservation issues of this region, such as competition for
forage between wild and domestic herbivores and human-wildlife conflicts need to be
addressed in a participatory manner. We suggest an alternative scheme to look at the
zonation of existing PAs and also the Trans-Himalayan region as a whole, to facilitate
better conservation in the region. Also, we emphasize that there is a vital need for
additional resources and a formal setup for regional planning and management under a
centrally sponsored scheme such as the 'Project Snow Leopard'.
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Bhatnagar, Y. V., Stakrey, R. W., & Jackson, R. (2000). A Survey of Depredation and Related Wildlife-Human Conflicts in Hemis National Park, Ladakh (India) (Vol. xvi). Seattle: Islt.
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Bhatnagar, Y. V. (1997). Ranging and Habitat Use by Himalayan Ibex (Capra ibex sibirica) in Pin Valley National Park. Ph.D. thesis, Saurashtra University, .
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Suryawanshi, K. R., Bhatnagar, Y., & Mishra, C. (2009). Why should a grazer browse? Livestock impact on winter resource use by bharal Pseudois nayaur
. Oecologia, , 1–10.
Abstract: Many mammalian herbivores show a temporal diet variation between graminoid-dominated and browse dominated diets. We determined the causes of such a diet shift and its implications for conservation of a medium sized ungulate-the bharal Pseudois nayaur. Past studies show that the bharal diet is dominated by graminoids (>80%) during summer, but the contribution of graminoids declines to about 50% in winter. We tested the predictions generated by two alternative hypotheses explaining the decline: low graminoid availability during winter causes bharal to include browse in their diet; bharal include browse, with relatively higher nutritional quality, in their diet to compensate for the poor quality of graminoids during winter. We measured winter graminoid availability in areas with no livestock grazing, areas with relatively moderate livestock grazing, and those with intense livestock grazing pressures. The chemical composition of plants contributing to the bharal diet was analysed. The bharal diet was quantiWed through signs of feeding on vegetation at feeding locations. Population structures of bharal populations were recorded using a total count method. Graminoid availability was highest in areas without livestock grazing, followed by areas with moderate and intense livestock grazing. The bharal diet was dominated by graminoids (73%) in areas with highest graminoid availability. Graminoid contribution to the bharal diet declined monotonically (50, 36%) with a decline in graminoid availability. Bharal young to female ratio was 3 times higher in areas with high graminoid availability than areas with low graminoid availability. The composition of the bharal winter diet was governed predominantly by the availability of graminoids in the rangelands. Our results suggest that bharal include more browse in their diet during winter due to competition from livestock for graminoids. Since livestock grazing reduces graminoid availability, creation of livestock-free areas is necessary for the conservation of grazing species such as the bharal and its predators including the endangered snow leopard in the Trans-Himalaya.
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