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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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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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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. (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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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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Jumabay, K., Wegge, P., Mishra, C., Sharma, K. (2013). Large carnivores and low diversity of optimal prey: a comparison of the diets of snow leopards Panthera uncia and wolves Canis lupus in Sarychat-Ertash Reserve in Kyrgyzstan. Oryx, , 1–7.
Abstract: In the cold and arid mountains of Central Asia, where the diversity and abundance of wild ungulates
are generally low, resource partitioning among coexisting carnivores is probably less distinct than in prey-rich areas. Thus, similar-sized carnivores are likely to compete for food. We compared the summer diets of snow leopards Panthera uncia and wolves Canis lupus in Sarychat-Ertash Reserve in the Tien-Shan mountains of Kyrgyzstan, based on analysis of genetically confirmed scats. Abundances of the principal prey species, argali Ovis ammon and Siberian ibex Capra sibirica, were estimated from field surveys. The diets consisted of few species, with high interspecific overlap (Pianka’s index50.91). Argali was the predominant prey, with .50% frequency of occurrence in both snow leopard and wolf scats. This was followed by Siberian ibex and marmots Marmota baibacina. Being largely unavailable, remains of livestock were not detected in any of the scats. In the snow leopard diet, proportions of argali and ibex were in line with the relative availabilities of these animals in the Reserve. This was in contrast to the diet of wolf, where argali occurred according to availability and ibex was significantly underrepresented. The high diet overlap indicates that the two predators might compete for food when the diversity of profitable, large prey is low. Competition may be more intense in winter, when marmots are not available. Hunting of argali and ibex outside the Reserve may be unsustainable and therefore reduce their abundances over time. This will affect both predators negatively and intensify competition for food. Reduction in ibex populations will directly affect the snow leopard, and the wolf is likely to be indirectly affected as a result of increased snow leopard predation of argali. |
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Chetri, M., Odden, M., Wegge, P. (2017). Snow Leopard and Himalayan Wolf: Food Habits and Prey Selection in the Central Himalayas, Nepal. Plos, (12(2)), 2–16.
Abstract: Top carnivores play an important role in maintaining energy flow and functioning of the ecosystem,
and a clear understanding of their diets and foraging strategies is essential for developing effective conservation strategies. In this paper, we compared diets and prey selection of snow leopards and wolves based on analyses of genotyped scats (snow leopards n = 182, wolves n = 57), collected within 26 sampling grid cells (5×5 km) that were distributed across a vast landscape of ca 5000 km2 in the Central Himalayas, Nepal. Within the grid cells, we sampled prey abundances using the double observer method. We found that interspecific differences in diet composition and prey selection reflected their respective habitat preferences, i.e. snow leopards significantly preferred cliff-dwelling wild ungulates (mainly bharal, 57% of identified material in scat samples), whereas wolves preferred typically plain-dwellers (Tibetan gazelle, kiang and argali, 31%). Livestock was consumed less frequently than their proportional availability by both predators (snow leopard = 27%; wolf = 24%), but significant avoidance was only detected among snow leopards. Among livestock species, snow leopards significantly preferred horses and goats, avoided yaks, and used sheep as available. We identified factors influencing diet composition using Generalized Linear Mixed Models. Wolves showed seasonal differences in the occurrence of small mammals/ birds, probably due to the winter hibernation of an important prey, marmots. For snow leopard, occurrence of both wild ungulates and livestock in scats depended on sex and latitude. Wild ungulates occurrence increased while livestock decreased from south to north, probably due to a latitudinal gradient in prey availability. Livestock occurred more frequently in scats from male snow leopards (males: 47%, females: 21%), and wild ungulates more frequently in scats from females (males: 48%, females: 70%). The sexual difference agrees with previous telemetry studies on snow leopards and other large carnivores, and may reflect a high-risk high-gain strategy among males. |
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Khanal, G., Poudyal, L. P., Devkota, B. P., Ranabhat, R., Wegge, P. (2018). Status and conservation of the snow leopard Panthera uncia in Api Nampa Conservation Area, Nepal. Fauna & Flora International, , 1–8.
Abstract: The snow leopard Panthera uncia is globally
threatened and reliable information on its abundance, distribution and prey species is a prerequisite for its conservation. In October-November 2014 we assessed the distribution of the snow leopard in the recently established Api Nampa Conservation Area in the Nepal Himalayas. Within selected blocks we conducted sign surveys and counted the number of bharal Pseudois nayaur, its principal wild prey, along transects totalling 106 km.We recorded 203 putative snow leopard signs at an encounter rate of 1.91 signs/km. Generalized linear models of the number of signs detected per transect showed that elevation had a positive influence and human activities a negative influence on sign encounter rate; prey abundance had only a weak positive influence on sign encounter rate. Within the effectively surveyed area of c. 2002 km2, we counted 527 bharal at an estimated density of 2.28 animals/km2. Recruitment of bharal was low, estimated at 48 kids/100 adult females, most likely a result of poor or overgrazed rangeland. We estimate the total number of bharal in this conservation area to be .>1,000, a prey base that could sustain 6-9 snow leopards. Based on our field observations, we identified human disturbance and habitat degradation associated with extraction of non-timber forest products, livestock grazing, and poaching as the main threats to the snow leopard. Standardized sign surveys, preferably supplemented by sampling with remote cameras or with genetic analysis of scats would provide robust baseline information on the abundance of snow leopards in this conservation area. |
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Chetri, M., Odden, M., Devineau, O., McCarthy, T., Wegge, P. (2020). Multiple factors influence local perceptions of snow leopards and
Himalayan wolves in the central Himalayas, Nepal. PeerJ, , 1–18.
Abstract: An understanding of local perceptions of carnivores is
important for conservation and management planning. In the central Himalayas, Nepal, we interviewed 428 individuals from 85 settlements using a semi-structured questionnaire to quantitatively assess local perceptions and tolerance of snow leopards and wolves. We used generalized linear mixed effect models to assess influential factors, and found that tolerance of snow leopards was much higher than of wolves. Interestingly, having experienced livestock losses had a minor impact on perceptions of the carnivores. Occupation of the respondents had a strong effect on perceptions of snow leopards but not of wolves. Literacy and age had weak impacts on snow leopard perceptions, but the interaction among these terms showed a marked effect, that is, being illiterate had a more marked negative impact among older respondents. Among the various factors affecting perceptions of wolves, numbers of livestock owned and gender were the most important predictors. People with larger livestock herds were more negative towards wolves. In terms of gender, males were more positive to wolves than females, but no such pattern was observed for snow leopards. People’s negative perceptions towards wolves were also related to the remoteness of the villages. Factors affecting people’s perceptions could not be generalized for the two species, and thus need to be addressed separately. We suggest future conservation projects and programs should prioritize remote settlements. |