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Xu, F., Ma, M., & Wu, Y. - Q. (2007). Population density and habitat utilization of ibex in Tomur National Nature Reserve,Xinjiang,China.
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Zhiryakov V.A. (2002). Ecology and behavior of the Snow leopard in Kazakhstan (Vol. N 1-4.).
Abstract: The data on spreading, numbers and population density of snow leopard in Kazakhstan are given in this article. The total number of the snow leopard in Kazakhstan is evaluated in 100-110 individuals. The everywhere occurred numbers' reduction under the influence of the anthropogenic factors is observed. The snow leopard' inhabitation area varies from 20 to 120 square kilometers depending on its regions. Sex and composition of the population and its aggregative behavior are given. The dynamics of numbers and mortality are estimated.
Keywords: Kazakhstan; distribution; number; density; population size; habitats; marking; Migration; diet; prey species; hunting; faeces; Sex; Age; population dynamics; reproductive activity; competitors; mortality; snow leopard.; 8810; Russian
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Christiansen, P. (2007). Canine morphology in the larger Felidae: implications for feeding ecology. Biological Journal of the Linnean Society, 91, 573–592.
Abstract: Canine morphology is analysed at seven intervals along the crown in both
anteroposterior and lateromedial perspective in seven species of large felids. The puma and the snow leopard have stout, rather conical canines, whereas those of lions, jaguars, and tigers bear substantial resemblance to each other, reflecting their phylogenetic relationships, and are less conical and large. The canines of the leopard are intermediate in morphology between those of the other species, probably reflecting its more generalized diet. The clouded leopard has very large and blade-like canines, which are different from the other analysed species. Canine bending strengths to estimated bite forces appear to differ less among the species than morphology,indicating that the evolution of canines has been constricted with respect to their strength in failure, probably owing to their being equally important for species fitness. However, the clouded leopard again stands out, having a high estimated bite force and rather weak canines in bending about the anteroposterior as well as lateromedial planes compared to the other species. Canine morphology to some extent reflects differences in killing mode, but also appears to be related to the phylogeny. The marked divergence of the clouded leopard is presently not understood. |
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Ulmer, F. A. (1966). Voices of the Felidae. Stock, , 259–262.
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Alexander, J. S., Gopalswamy, A. M., Shi, K., Riordan, P. (2015). Face Value: Towards Robust Estimates of Snow Leopard Densities. Plos One, .
Abstract: When densities of large carnivores fall below certain thresholds, dramatic ecological effects
can follow, leading to oversimplified ecosystems. Understanding the population status of such species remains a major challenge as they occur in low densities and their ranges are wide. This paper describes the use of non-invasive data collection techniques combined with recent spatial capture-recapture methods to estimate the density of snow leopards Panthera uncia. It also investigates the influence of environmental and human activity indicators on their spatial distribution. A total of 60 camera traps were systematically set up during a three-month period over a 480 km2 study area in Qilianshan National Nature Reserve, Gansu Province, China. We recorded 76 separate snow leopard captures over 2,906 trapdays, representing an average capture success of 2.62 captures/100 trap-days. We identified a total number of 20 unique individuals from photographs and estimated snow leopard density at 3.31 (SE = 1.01) individuals per 100 km2. Results of our simulation exercise indicate that our estimates from the Spatial Capture Recapture models were not optimal to respect to bias and precision (RMSEs for density parameters less or equal to 0.87). Our results underline the critical challenge in achieving sufficient sample sizes of snow leopard captures and recaptures. Possible performance improvements are discussed, principally by optimising effective camera capture and photographic data quality. |
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Alexander, S., A., Zhang, C., Shi, K., Riordan, P. (2016). A granular view of a snow leopard population using camera traps in Central China. Biological Conservation, (197), 27–31.
Abstract: Successful conservation of the endangered snow leopard (Panthera uncia) relies on the effectiveness of monitoring programmes. We present the results of a 19-month camera trap survey effort, conducted as part of a longterm study of the snow leopard population in Qilianshan National Nature Reserve of Gansu Province, China. Weassessed the minimumnumber of individual snowleopards and population density across different sampling periods using spatial capture–recapture methods. Between 2013–2014, we deployed 34 camera traps across an area of 375 km2, investing a total of 7133 trap-days effort. Weidentified a total number of 17–19 unique individuals
from photographs (10–12 adults, five sub-adults and two cubs). The total number of individuals identified and estimated density varied across sampling periods, between 10–15 individuals and 1.46–3.29 snow leopards per 100 km2 respectively. We demonstrate that snow leopard surveys of limited scale and conducted over short sampling periods only present partial views of a dynamic and transient system.We also underline the challenges in achieving a sufficient sample size of captures and recaptures to assess trends in snow leopard population size and/or density for policy and conservation decision-making |
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Chetri, M., Odden, M., Sharma, K., Flagstad, O., Wegge, P. (2019). Estimating snow leopard density using fecal DNA in a large landscape in north-central Nepal. Global Ecology and Conservation, (17), 1–8.
Abstract: Although abundance estimates have a strong bearing on the conservation status of a
species, less than 2% of the global snow leopard distribution range has been sampled systematically, mostly in small survey areas. In order to estimate snow leopard density across a large landscape, we collected 347 putative snow leopard scats from 246 transects (490 km) in twenty-six 5 5km sized sampling grid cells within 4393 km2 in Annapurna- Manaslu, Nepal. From 182 confirmed snow leopard scats, 81 were identified as belonging to 34 individuals; the remaining were discarded for their low (<0.625) quality index. Using maximum likelihood based spatial capture recapture analysis, we developed candidate model sets to test effects of various covariates on density and detection of scats on transects. The best models described the variation in density as a quadratic function of elevation and detection as a linear function of topography. The average density estimate of snow leopards for the area of interest within Nepal was 0.95 (SE 0.19) animals per 100 km2 (0.66e1.41 95% CL) with predicted densities varying between 0.1 and 1.9 in different parts, thus highlighting the heterogeneity in densities as a function of habitat types. Our density estimate was low compared to previous estimates from smaller study areas. Probably, estimates from some of these areas were inflated due to locally high abundances in overlap zones (hotspots) of neighboring individuals, whose territories probably range far beyond study area borders. Our results highlight the need for a large-scale approach in snow leopard monitoring, and we recommend that methodological problems related to spatial scale are taken into account in future snow leopard research. |
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Zhang, L., Lian, X., Yang, X. (2020). Population density of snow leopards (Panthera Uncia) in the Yage Valley Region of the Sanjiangyuan National Park: Conservation Implications and future directions. Artic, Antartic and Alpine Research, 52(1), 541–550.
Abstract: Population-based studies on snow leopard (Panthera uncia) are of theoretical and practical sig- nificance for the conservation of alpine ecosystems, though geographic remoteness and isolation hinder surveys in many promising regions. The Sanjiangyuan National Park on the Tibetan Plateau is acknowledged as a main snow leopard habitat, but most of the region remains unexplored and unknown. We adopted a combined approach of route survey and camera trapping survey to explore the population density of snow leopard in the Yage Valley region of the Sanjiangyuan National Park. Results indicated that (1) large populations of blue sheep contributed to the major food supply for snow leopards, along with diverse prey species as dietary supplementations, and (2) a population density of four to six snow leopards per 100 km2 on the north bank was estimated, and nine to fourteen individuals within the valley core areas were identified. We also argue that under the potential impacts of hydropower dams, this valley ecosystem should be symbolized as a conservation hotspot and therefore merits prioritized conservation. We recommend further surveys combined with novel methods/techniques and advocate a sustainable ecotourism model for the first V-shaped valley along the Yangtze mainstream.
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Sharma, R. K., Sharma, K., Borchers, D., Bhatnagar, Y. V., Suryawanshi, K. S., Mishra, C. (2020). Spatial variation in population-density, movement and detectability of snow leopards in
2 a multiple use landscape in Spiti Valley, Trans-Himalaya. bioRxiv, .
Abstract: The endangered snow leopard Panthera uncia occurs in human use landscapes in the mountains of South and Central Asia. Conservationists generally agree that snow leopards must be conserved through a land-sharing approach, rather than land-sparing in the form of strictly protected areas. Effective conservation through land-sharing requires a good understanding of how snow leopards respond to human use of the landscape. Snow leopard density is expected to show spatial variation within a landscape because of variation in the intensity of human use and the quality of habitat. However, snow leopards have been difficult to enumerate and monitor. Variation in the density of snow leopards remains undocumented, and the impact of human use on their populations is poorly understood. We examined spatial variation in snow leopard density in Spiti Valley, an important snow leopard landscape in India, via spatially explicit capture recapture analysis of camera trap data. We camera trapped an area encompassing a minimum convex polygon of 953 km . We estimated an overall density of 0.49 (95% CI: 0.39-0.73) adult snow leopards per 100 km . Using AIC, our best model showed the density of snow leopards to depend on wild prey density, movement about activity centres to depend on altitude, and the expected number of encounters at the activity centre to depend on topography. Models that also used livestock biomass as a density covariate ranked second, but the effect of livestock was weak. Our results highlight the importance of maintaining high density pockets of wild prey populations in multiple use landscapes to enhance snow leopard conservation.
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Thapa, K., Jackson, R., Gurung, L, Acharya, H. B., Gurung, R. K.,. (2021). Applying the double observer methodology for assessing blue sheep population size in Nar Phu valley, Annapurna Conservation Area, Nepal. Wildlife Biology, , 1–11.
Abstract: This study was undertaken in spring, 2019 to assess the applicability of the double-observer survey method for estimating blue sheep Pseudois nayaur abundance in Nar-Phu valley of Manang District located in Annapurna Conservation Area of northern Nepal. Since counting large mammals in rugged mountain habitat poses a special challenge, we tested the efficacy of the double observer method for generating robust population estimates for this important protected area. The overall detection probability for observers (O1 and O2) was 0.94 and 0.91 for a total of 106 groups comprised of 2059 individual blue sheep. We estimated the area’s blue sheep population at 2070 (SE ± 168.77; 95% CI 2059–2405) for the 246.2 km2 of sampled habitat. We determined blue sheep to be widely distributed within the study area with a mean density of 8.4 individuals per km2 based on a total study area of 246.2 km2. We discuss demographic population structure and identify limitations when applying the double observer approach, along with recommending viewshed mapping for ensuring more robust density estimates of mountain-dwelling ungulates like blue sheep or ibex that inhabit extremely heterogeneous terrain which strongly influences sighting distances and overall animal detection rates.
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