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Wang, X., Peng, J., & Zhou, H. (2000). Preliminary observations on the distribution and status of dwarf blue sheep Pseudois schaeferi. Oryx, 34(1), 21–26.
Abstract: Describes the drastic decline of the dwarf blue sheep since the 1950's primarily due to over-hunting. There are an estimated 200 individuals remaining in a 295 square km range in Batang county, China. The authors recommend urgent protection for this species.
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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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Harris, R. B., Pletscher, D. H., Loggers, C. O., & Miller, D. J. (1999). Status and trends of Tibetan plateau mammalian fauna, Yeniugou, China. Biological Conservation, 87, 13–19.
Abstract: We conducted surveys focusing on the unique and vulnerable ungulate species in Yeniugou, Qinghai province, China, during September 1997 to compare population estimates with those from the early 1990s. The status of two ungulate species appeared essentially unchanged since 1990ñ1992: wild yak Bos grunniens (about 1200 to 1300 animals) and Tibetan gazelle Procapra picti- caudata. The status of one ungulate species, the white-lipped deer Cervus albirostris, appeared to improve, from a very few to close to 100. We are unsure how the status of the Tibetan wild ass Equus kiang compares with that of the early 1990s. The status of three species declined during the period: blue sheep Pseudois nayaur and argali Ovis ammon declined slightly (possibly due to a weather event), and the Tibetan antelope Pantholops hodgsoni declined dramatically (probably due primarily to poaching), from over 2000 estimated in 1991 to only two seen during 1997. Poaching of antelope has become a serious problem throughout the Tibetan plateau in recent years, and this survey provides evidence that an entire subpopulation can disappear (either through mortality, movement away from human disturbance or a combination) within a relatively short time-frame. That some species (e.g. wild yak, white-lipped deer) continue to thrive in Yeniugou is heartening, but even they remain vulnerable to market-driven poaching.#1998 Elsevier Science Ltd. All rights reserved.
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