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Shrestha, R., & Wegge, P. (2008). Habitat relationships between wild and domestic herbivores in Nepalese trans – Himalaya. Journal of Arid Environments, 72, 914–925.
Abstract: In the semi-arid ecosystems of Asia, where pastoralism is a main subsistence occupation, grazing competition from domestic stock is believed to displace the wild ungulates. We studied the habitat relationships among sympatric naur and domestic yak and smallstock in Phu valley in upper Manang district, Nepal, on the basis of their distribution on vegetation types, elevation and slope. To control for the disturbance effect by humans, we collected the data on naur from those ranges where domestic stock were not being attended by herders. We applied correspondence analysis to explore habitat associations among animal groups (n ¬ 1415) within and across-seasons. Within each association, interspecific habitat overlaps and species habitat preferences were calculated. Naur was strongly associated with free-ranging yak as they used similar altitudinal ranges in all seasons, except in spring. Their distributions on vegetation types and slopes were also quite similar, except for a stronger preference for alpine meadows by naur during summer and winter. Naur and smallstock did not form temporal associations as the latter consistently used lower elevations. In autumn and spring, however, naur spatially overlapped with the summer range of smallstock, and both preferred the alpine meadow habitat during these periods. Alpine meadow was the least abundant vegetation type but was consistently and preferentially used by all animal groups across seasons. At high stocking densities, all three animals groups are therefore likely to compete for this vegetation type. The role of spatio-temporal heterogeneity for interpreting the interspecific relationships among ungulates in the semi-arid rangelands of the trans-Himalaya is discussed.
Keywords: blue sheep; Competition; domestic; habitat partitioning; naur; Nepal; pastoralism; pseudois nayaur; trans-himalaya
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Shrestha, R., & Wegge, P. (2006). Determining the composition of herbivore diets in the Trans-Himalayan rangelands: A comparison of field methods. Journal of Rangeland Ecology and Management, 59(5), 512–518.
Abstract: In late summer, in a semi-arid mountain range in Nepal, we compared 3 field methods for determining the botanical composition of herbivore diets. Data were collected from the same animals belonging to 1 herd of domestic yak (Bos grunniens) and 2 herds of mixed smallstock, consisting of domestic goats (Capra hircus) and sheep (Ovis aries). Bite count, feeding site examination, and microhistological analysis of feces gave different estimates of forage categories and plant species in both animal groups. Because yaks grazed in other vegetation communities when not observed for bite-counts and feeding signs, the results from the latter methods could not be compared directly with that from fecal analysis. In smallstock, feeding site examination gave higher estimates of graminoids and lower estimates of shrubs than the other 2 methods, probably because all feeding signs on shrubs were not detected. Bite-counts and fecal analysis gave comparable results, except that forbs were underestimated by fecal analysis, presumably due to their more complete digestion. Owing to the difficulty in collecting samples that are representative of the entire grazing period and the problem of recording feeding signs correctly, both feeding site examination and bite-counts are unsuitable methods for studying the food habits of free ranging domestic and wild herbivores. Microhistological analysis of feces appears to be the most appropriate method, but correction factors are needed to adjust for differential digestion. The systematic use of photomicrographs improves the speed and accuracy of the fecal analysis.
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Wegge, P., Shrestha, R., Flagstad, O. (2012). Snow leopard Panthera uncia predation on livestock and wild prey in a mountain valley in northern Nepal: implications for conservation management. Wildlife Biology, 18(10.2981/11-049), 131–141.
Abstract: The globally endangered snow leopard Panthera uncia is sparsely distributed throughout the rugged mountains in Asia.
Its habit of preying on livestock poses a main challenge to management. In the remote Phu valley in northern Nepal, we obtained reliable information on livestock losses and estimated predator abundance and diet composition from DNA analysis and prey remains in scats. The annual diet consisted of 42%livestock. Among the wild prey, bharal (blue sheep/ naur) Pseudois nayaur was by far the most common species (92%). Two independent abundance estimates suggested that there were six snow leopards in the valley during the course of our study. On average, each snow leopard killed about one livestock individual and two bharal permonth. Predation loss of livestock estimated fromprey remains in scats was 3.9%, which was in concordance with village records (4.0%). From a total count of bharal, the only large natural prey in the area and occurring at a density of 8.4 animals/km2 or about half the density of livestock, snow leopards were estimated to harvest 15.1% of the population annually. This predation rate approaches the natural, inherent recruitment rate of this species; in Phu the proportion of kids was estimated at 18.4%. High livestock losses have created a hostile attitude against the snow leopard and mitigation measures are needed. Among innovative management schemes now being implemented throughout the species’ range, compensation and insurance programmes coupled with other incentive measures are encouraged, rather than measures to reduce the snow leopard’s access to livestock. In areas like the Phu valley, where the natural prey base consists mainly of one ungulate species that is already heavily preyed upon, the latter approach, if implemented, will lead to increased predation on this prey, which over time may suppress numbers of both prey and predator. |
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Forrest, J. L., Wikramanayake, E., Shrestha, R., Areendran, G., Gyeltshen, K., Maheshwari, A., Mazumdar, S., Naidoo, R., Thapa, G. J., Thapa, K. (2012). Conservation and climate change: Assessing the vulnerability of snow leopard habitat to treeline shift in the Himalaya. Biological Conservation, 150, 129–135.
Abstract: Climate change is likely to affect the persistence of large, space-requiring species through habitat shifts,
loss, and fragmentation. Anthropogenic land and resource use changes related to climate change can also impact the survival of wildlife. Thus, climate change has to be integrated into biodiversity conservation plans. We developed a hybrid approach to climate-adaptive conservation landscape planning for snow leopards in the Himalayan Mountains. We first mapped current snow leopard habitat using a mechanistic approach that incorporated field-based data, and then combined it with a climate impact model using a correlative approach. For the latter, we used statistical methods to test hypotheses about climatic drivers of treeline in the Himalaya and its potential response to climate change under three IPCC greenhouse gas emissions scenarios. We then assessed how change in treeline might affect the distribution of snow leopard habitat. Results indicate that about 30% of snow leopard habitat in the Himalaya may be lost due to a shifting treeline and consequent shrinking of the alpine zone, mostly along the southern edge of the range and in river valleys. But, a considerable amount of snow leopard habitat and linkages are likely to remain resilient to climate change, and these should be secured. This is because, as the area of snow leopard habitat fragments and shrinks, threats such as livestock grazing, retaliatory killing, and medicinal plant collection can intensify. We propose this approach for landscape conservation planning for other species with extensive spatial requirements that can also be umbrella species for overall biodiversity. 2012 Elsevier Ltd. All rights reserved |
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Shrestha, R., & Wegge, P. (2008). Wild sheep and livestock in Nepal Trans-Himalaya: coexistence or competition? Environmental Conservation, 32(2), 125–136.
Abstract: Excessive grazing by livestock is claimed to displace wild ungulates in the Trans-Himalaya. This study compares the seasonal diets and habitat use of sympatric wild naur Pseudois nayaur and domestic goat Capra hircus, sheep Ovis aries and free-ranging yak Bos grunniens in north Nepal and analyses their overlap both within and across seasons. Alpinemeadow and the legumes Oxytropis and Chesneya were critical resources for all animal groups. High overlap occurred cross-seasonally when smallstock (sheep and goats) in summer used the spring and autumn ranges of naur. Relatively high total ungulate biomass (3028 kg km-2) and low recruitment of naur (56 young per 100 adult females in autumn) suggested interspecific competition. The spatio-temporal heterogeneity in composition and phenology of food plants across the steep gradient of altitude, together with rotational grazing, appears to indirectly facilitate coexistence of naur and smallstock. However, owing to high crossseasonal (inter-seasonal) overlaps, competition is likely to occur between these two groups at high stocking densities. Within seasons, naur overlapped more with free-ranging yak than with smallstock. As their habitat use and diets were most similar in winter, when both fed extensively on the same species of shrubs, naur was most likely to compete with yak during that season.
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Shrestha, R., Wegge, P., & Koirala, R. A. (2005). Summer diets of wild and domestic ungulates in Nepal Himalaya. Journal of Zoology, 266, 111–119.
Abstract: The selection of summer forage by three sympatric ungulates in the Damodar Kunda region of upper Mustang in
north Nepal was studied to assess the extent of food overlap between them. To compare their diets, a microhistological technique of faecal analysis was used, adjusted for inherent biases by comparing it with bite-count data obtained in domestic goats. Tibetan argali Ovis ammon hodgsoni, naur (blue sheep or bharal) Pseudois nayaur and domestic goat Capra hircus consumed mostly forbs, graminoids and browse, respectively. The proportions of food items in their diets were significantly different both at the plant species (P<0.02) and at the forage category level (P<0.001). Except for sharing three common plants (Agrostis sp., Stipa sp. and Potentilla fruticosa), dietary overlap at the species level was quite low. At the forage category level, naur and domestic goat overlapped more than the other ungulate pairs. Although all three species were opportunistic, mixed feeders, argali was a more selective forb specialist grazer than the other two ungulates. Owing to some spatial separation and little dietary overlap, interspecific competition for summer forage was low. If animal densities increase, however, goats are expected to compete more with naur than with argali because of their more similar diets. Owing to differences in forage selection by argali and naur throughout their large geographical ranges, reflecting adaptations to local ecological conditions, inferences regarding forage competition between domestic livestock and these two wild caprins need to be made from local, site-specific studies, rather than from general diet comparisons. |
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Pandey, B. P., Thami, S., Shrestha, R., Subedi, N., Chalise, M. K., Ale, S. B. (2021). Snow leopards and prey in Rolwaling Valley, Gaurishankar Conservation Area, Nepal. CATnews, 74(Windter 2021), 14–19.
Abstract: The snow leopard Panthera uncia, an apex predator of the Himalayan ecosystem, often shares habitat with the wolf, Canis lupus, red fox Vulpes vulpes, and other carnivores. A biodiversity monitoring programme primarily focused on the assessment of the status of snow leopard and its prey in Rolwaling valley of Gaurishankar Conservation Area, Nepal, was carried out during June–November 2019. We deployed single camera traps in each of twelve grids sized 16 km2 each, operated 24 hours, and left alone for the whole study period. A single snow leopard was captured thrice on same camera in Rhododendron anthopogon-Hippophae thibetana scrubland, near Tsho Rolpa glacial lake (4,536 m). Alongwith snow leopard, wolves were also photographed at three sites namely Yelung pass (4,956 m), Tsho Rolpa (4,536 m) and Dudhkunda ridgeline (5,091 m). The red fox was the most frequent predator in Rolwaling while stone marten Martes foina, yellow-throated marten Martes flabigula, and yellow-belied weasel Mustella katiyah were captured occasionally. Photo capture rate index PCRI per 100 trap nights was calculated for all identifiable species where snow leopard and wolf had PCRI values of 0.35 and 0.71, respectively. The Cumulative PCRI values suggest a pyramid shaped community structure in Rolwaling with small herbivores (including game birds) with broad base (PCRI 22.29) followed by large herbivores (10.38) and small-medium sized carnivores (6.96). The top predators (snow leopard and wolf) produces 1.06 photographic rate index. The declaration of Gaurishankar conservation area and continuous efforts from conservation area management committees, strict cultural rules from local Buddhist community in the valley are found possibly favoured the recolonization of the wolf and frequent visits by snow leopard.
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