Abstract: The loss of mammalian herbivores from grazing ecosystems has become a major concern,and efforts to stem such losses are stymied by lack of information on the proximate and ultimate factors influencing their distributions and diversity patterns. This research investigated the distribution, species-richness patterns and underlying mechanisms in mammalian herbivores of the Trans-Himalayan region of Ladakh, India. It adopted a multi-spatial approach to understand these issues in the little-known herbivore assemblage of the region. Since vegetation is the most important factor that determines the distribution of herbivores, first I researched the distribution and abundance patterns of vascular plants along an altitudinal gradient at different spatial scales. Both plant species-richness and aboveground biomass showed a hump-shaped relationship with altitude. Such a relationship in case of species-richness is expected, but it is contrary to my expectation of a negative linear relationship, in case of abundance. I relate this unexpected pattern to the limited precipitation and pervasive livestock grazing at lower altitudes in this dry alpine environment. I then investigated the biogeography of mammalian herbivores, and found that they form geographical groups on the basis of their evolutionary histories. Subsequently, I assessed the niche relationship between Asiatic ibex Capra ibex siberica and blue sheep Pseudois nayaur, the most common large herbivores in Ladakh, to see whether local level processes like competition generate spatial pattern of herbivore species-richness. The results showed that blue sheep constrains the distribution of ibex, which implies that competition amongst native species does play a role in structuring large herbivore assemblages in the region. Recognising the lack of information on large herbivores’ niche variation across assemblages, I also studied blue sheep’s niche width in relation to herbivore speciesrichness. It became apparent that the species’ niche varies across assemblages with different number of sympatric species, which could negatively influence the animal’s reproductive performance and population. Finally, I asked if the distributional range of the endangered Ladakh urial Ovis vignei vignei is constrained by the abundant blue sheep, and found that these two species associate randomly at large geographical scales, but cooccur at the landscape level as a result of local habitat-level resource partitioning. These results contribute towards understanding the mechanisms responsible for the formation and maintenance of large herbivore assemblages in the Trans-Himalaya and other mountainous regions of the world.

Abstract: A survey of the winter birds of the Gya-Miru Wildlife Sanctuary in the Trans-Himalayan region of Ladakh, India was carried out between December 2002 and March 2003. 30 species were recorded, constituting 60% of the total resident species in Ladakh excluding Nubra Valley, and 10% of the total birds recorded in Ladakh (11% of the post-1960 records). 29 species (97%) of the birds recorded breed in Ladakh, while one, Mallard Anas platyrhynchos is a passage migrant. The most noteworthy sightings were four species of pheasants (Phasianidae) and two of owls (Strigidae). A preliminary assessment of the potential threats to the birds in the reserve was made. This is the first avifaunal survey of the reserve, and has implications for assessing the importance of the area for bird protection.

Abstract: The loss of livestock to wild predators is an important livelihood concern among Trans-Himalayan pastoralists. Because of the remoteness and inaccessibility of the region, few studies have been carried out to quantify livestock depredation by wild predators. In the present study, we assessed the intensity of livestock depredation by snow leopard Uncia uncia, Tibetan wolf Canis lupus chanku, and Eurasian lynx Lynx l. isabellina in three villages, namely Gya, Rumtse, and Sasoma, within the proposed Gya-Miru Wildlife Sanctuary in Ladakh, India. The three villages reported losses of 295 animals to these carnivores during a period of 2.5 years ending in early 2003, which represents an annual loss rate of 2.9% of their livestock holdings. The Tibetan wolf was the most important predator, accounting for 60% of the total livestock loss because of predation, followed by snow leopard (38%) and lynx (2%). Domestic goat was the major victim (32%), followed by sheep (30%), yak (15%), and horse (13%). Wolves killed horses significantly more and goats less than would be expected from their relative abundance. Snow leopards also killed horses significantly more than expected, whereas they killed other livestock types in proportion to their abundance. The three villages combined incurred an estimated annual monetary loss of approximately $USD 12,120 amounting to approximately $USD 190/household/y. This relatively high total annual loss occurred primarily because of depredation of the most valuable livestock types such as yak and horse. Conservation actions should initially attempt to target decrease of predation on these large and valuable livestock species.