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Mishra, C., Van Wieren S., Ketner, P., Heitkonig, I., & Prins H. (2004). Competition between domestic livestock and wild bharal Pseudois nayaur in the Indian Trans-Himalaya. Journal of Animal Ecology, 73, 344–354.
Abstract: 1. The issue of competition between livestock and wild herbivores has remained contentious. We studied the diets and population structures of the mountain ungulate bharal Pseudois nayaur and seven species of livestock to evaluate whether or not they compete for forage. The study was conducted in the high altitude Spiti Valley, Indian Trans-Himalaya.
2. We compared resource (forage) availability and bharal population structures between rangelands differing in livestock density. Forage availability was estimated by clipping the standing graminoid biomass in sample plots. Livestock and bharal population structures were quantified through annual censuses. Seasonal diets of livestock were studied by direct observations, while those of bharal were quantified through feeding
signs on vegetation.
3. We found that livestock grazing causes a significant reduction in the standing crop of forage. Graminoid availability per unit livestock biomass was three times greater in a moderately grazed rangeland compared with an intensively grazed one.
4. There was considerable diet overlap among the herbivore species. In summer, bharal, yak Bos grunniens, horse Equus caballus, cow Bos indicus, and dzomo (yak-cow hybrids) fed predominantly on graminoids, while donkey E. asinus, sheep Ovis aries, and goat Capra hircus, consumed both graminoids and herbs. The summer diet of bharal was a subset of the diets of three livestock species. In winter, depleted graminoid availability caused bharal, yak and horse to consume relatively more herbs, while the remaining livestock species fed predominantly on graminoids. Diet overlap was less in winter but, in both seasons, all important forage species in the bharal diet were consumed
in substantial amounts by one or more species of livestock.
5. Comparison of the population structures of bharal between two rangelands differing in livestock density by
c. 30% yielded evidence of resource competition. In the intensively grazed rangeland, bharal density was 63% lower, and bharal population showed poorer performance (lower young : adult female ratios).
6.Synthesis and applications High diet overlap between livestock and bharal, together with density-dependent forage limitation, results in resource competition and a decline in bharal density. Under the present conditions of high livestock density and supplemental feeding, restricting livestock numbers and creating livestockfree areas are necessary measures for conserving Trans-Himalayan wild herbivores. Mediating competitive effects on bharal through supplemental feeding is not a feasible option.
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Lovari, S., Minder, I., Ferretti, F., Mucci, N., Randi, E., Pellizzi, B. (2013). Common and snow leopards share prey, but not habitats: competition avoidance by large predators. Journal of Zoology, 291, 127–135.
Abstract: Resource exploitation and behavioural interference underlie competition among
carnivores. Competition is reduced by specializing on different prey and/or spatiotemporal
separation, usually leading to different food habits. We predicted that
two closely related species of large cats, the endangered snow leopard and the
near-threatened common leopard, living in sympatry, would coexist through
habitat separation and exploitation of different prey species. In central Himalaya,
we assessed (2006–2010) habitat and diet overlap between these carnivores. The
snow leopard used grassland and shrubland, whereas the common leopard
selected forest. Contrary to our prediction, snow leopard and common leopard
preyed upon similar wild (Himalayan tahr, musk deer) and domestic species (Bos
spp., dogs). Dietary overlap between snow leopard and common leopard was 69%
(yearly), 76% (colder months) and 60% (warmer months). Thus, habitat separation
should be the result of other factors, most likely avoidance of interspecific
aggression. Habitat separation may not always lead to the use of different prey.
Avoidance of interspecific aggression, rather than exploitation of different
resources, could allow the coexistence of potentially competing large predators.
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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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Trivedi, P. (2009). Project Snow Leopard: Participatory conservation model for the Indian Himalaya. Mountain Forum Bulletin, Ix(2), 52–54.
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Suryawanshi, K. R., Bhatnagar, Y., & Mishra, C. (2009). Why should a grazer browse? Livestock impact on winter resource use by bharal Pseudois nayaur
. Oecologia, , 1–10.
Abstract: Many mammalian herbivores show a temporal diet variation between graminoid-dominated and browse dominated diets. We determined the causes of such a diet shift and its implications for conservation of a medium sized ungulate-the bharal Pseudois nayaur. Past studies show that the bharal diet is dominated by graminoids (>80%) during summer, but the contribution of graminoids declines to about 50% in winter. We tested the predictions generated by two alternative hypotheses explaining the decline: low graminoid availability during winter causes bharal to include browse in their diet; bharal include browse, with relatively higher nutritional quality, in their diet to compensate for the poor quality of graminoids during winter. We measured winter graminoid availability in areas with no livestock grazing, areas with relatively moderate livestock grazing, and those with intense livestock grazing pressures. The chemical composition of plants contributing to the bharal diet was analysed. The bharal diet was quantiWed through signs of feeding on vegetation at feeding locations. Population structures of bharal populations were recorded using a total count method. Graminoid availability was highest in areas without livestock grazing, followed by areas with moderate and intense livestock grazing. The bharal diet was dominated by graminoids (73%) in areas with highest graminoid availability. Graminoid contribution to the bharal diet declined monotonically (50, 36%) with a decline in graminoid availability. Bharal young to female ratio was 3 times higher in areas with high graminoid availability than areas with low graminoid availability. The composition of the bharal winter diet was governed predominantly by the availability of graminoids in the rangelands. Our results suggest that bharal include more browse in their diet during winter due to competition from livestock for graminoids. Since livestock grazing reduces graminoid availability, creation of livestock-free areas is necessary for the conservation of grazing species such as the bharal and its predators including the endangered snow leopard in the Trans-Himalaya.
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Mishra, C., Madhusudan, M. D., & Datta, A. (2006). Mammals of the high altitudes of western Arunachal Pradesh, eastern Himalaya: an assessment of threats and conservation needs (Vol. 40).
Abstract: The high altitudes of Arunachal Pradesh,India, located in the Eastern Himalaya biodiversity hotspot, remain zoologically unexplored and unprotected. We report results of recent mammal surveys in the high altitude habitats of western Arunachal Pradesh. A total of 35 mammal species (including 12 carnivores, 10 ungulates and 5 primates) were recorded, of which 13 are categorized as Endangered or Vulnerable on the IUCN Red List. One species of primate, the Arunachal macaque Macaca munzala, is new to science and the Chinese goral Nemorhaedus caudatus is a new addition to the ungulate fauna of the Indian subcontinent. We documented peoples' dependence on natural resources for grazing and extraction of timber and medicinal plants. The region's mammals are threatened by widespread hunting. The snow leopard Uncia uncia and dhole Cuon alpinus are also persecuted in retaliation for livestock depredation. The tiger Panthera tigris, earlier reported from the lower valleys, is now apparently extinct there, and range reductions over the last two decades are reported for bharal Pseudois nayaur and musk deer Moschus sp.. Based on mammal species richness, extent of high altitude habitat, and levels of anthropogenic disturbance, we identified a potential site for the creation of Arunachal's first high altitude wildlife reserve (815 km2). Community-based efforts that provide incentives for conservation-friendly practices could work in this area, and conservation awareness programmes are required, not just amongst the local communities and schools but for politicians, bureaucrats and the army.
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Singh, N. J. (2008). Animal – Habitat relationships in high altitude rangelands. Norway: University of Tromsø.
Abstract: This study conducted in the high altitude rangelands of Indian Transhimalaya, deals with basic questions regarding the ecology of an endangered species, the wildsheep Tibetan argali (Ovis ammon hodgsoni) and applied issues related to its conservation and potential conflict with the local nomadic pastoralists. The basic questions on ecology are aimed at delineating the habitat and resource selection processes, identifying factors causing sexual segregation and efficient surveying and sampling. The applied aspect focuses on the changing face of pastoralism and the potential impacts of modernising livestock husbandry on argali.
Overall, the study provides a general framework towards the understanding of argali-habitat relationships at different spatio-temporal scales. The spatial determinant associated with altitude in the area, predicts argali habitat and resource selection in this relatively homogenous landscape. These determine the range of other topographic variables and forage characteristics selected by argali. The selection of feeding patches in the selected range of altitude and topography is mainly characterised by their greenness and the quality of plant groups. Adjusting to changing forage quality, argali display an opportunistic feeding strategy, selecting grasses in early spring and switching to forbs later in summer. Nevertheless, the habitat selection process did not appear to differ among the sexes to drive sexual segregation. There was, however, strong segregation among the sexes as well as between lactating and non lactating females. The reasons for segregation appeared to be predominantly social, but driven ultimately by predation and concomitantly by resources. The habitat selection information was used to design a stratified random sampling strategy that led to i) a significant reduction in survey effort in sampling these sparsely distributed species and ii) reduction in sampling bias.
The applied aspect of the study outlines and evaluates the dramatic changes in the nomadic pastoralism that have occurred in the past five decades in the study area. These have led to a loss of pastures (-25 to -33%) of the nomads, consequent readjustment in traditional patterns of pasture use, intensified grazing pressures (25 to 70%) and rangeland degradation in the area. Such changes may have serious consequences on the survival of local wildlife, as tested with a study of the effects on argali of livestock presence and resource exploitation. Hence, a successful conservation and recovery strategy should focus on: minimising the impacts of livestock on argali, identifying the factors affecting the persistence of the current populations, increasing local sub populations of this species to prevent extinction due to stochastic events, prevent loss of genetic diversity and excessive fragmentation and thus ensuring gene flow.
Ecological Niche Factor Analyses (ENFA), bias-reduced logistic regression and Fuzzy correspondence analyses (FCA) were used to answer habitat and resource selection questions. A sexual segregation and aggregation statistic (SSAS) was used to estimate the components of sexual segregation and test segregation. SSAS combined with canonical correspondence analyses (CCA) allowed the estimation of segregation based on habitat variables. Logistic regression models were formulated to estimate models on which the stratified random sampling strategy was based. The 9 Animal – Habitat relationships in high altitude rangelands overall study also included surveys, interviews and literature reviews to understand the nomads’ movement and pasture use patterns of their livestock. Kernel density estimations (KDE) were used to estimate extent of range overlaps between livestock and argali.
Keywords: high altitude, homogeneous, argali, habitat selection, resource selection function, ENFA, stratified random sampling, sexual segregation, SSAS, livestock, predation, resources
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