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 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: Large carnivores are of vital importance to the stability and integrity of most ecosystems, but recent declines in free-ranging populations have highlighted the potentially devastating effect of infectious diseases on their conservation. We reviewed the literature on infectious diseases of 34 large (maximum body mass of adults >20 kg) terrestrial carnivore species, 18 of which are considered to be threatened in the wild, and examined reports of antibody prevalence (seroprevalence) and cases of infection, mortality and population decline. Of 52 diseases examined, 44% were viral, 31% bacterial and the remainder were protozoal or fungal. Many infections were endemic in carnivores and/or infected multiple taxonomic families, with the majority probably occurring via inhalation or ingestion. Most disease studies consisted of serological surveys for disease antibodies, and antibody detection tended to be widespread implying that exposure to micro-organisms was common. Seroprevalence was higher in tropical than temperate areas, and marginally higher for infections known to occur in multiple carnivore groups. Confirmation of active infection via micro-organism recovery was less common for ursids than other taxonomic groups. Published descriptions of disease-induced population decline or extinction were rare, and most outbreaks were allegedly the result of direct transmission of rabies or canine distemper virus (CDV) from abundant carnivore species to less-common large carnivores. We conclude that the threat of disease epidemics in large carnivores may be serious if otherwise lethal infections are endemic in reservoir hosts and transmitted horizontally among taxa. To prevent or mitigate future population declines, research efforts should be aimed at identifying both the diseases of potential importance to large carnivores and the ecological conditions associated with their spread and severity.