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Author Atzeni, L., Cushman, S. A., Bai, D., Wang, J., Chen, P., Shi, K., Riordan, P. url 
  Title (up) Meta-replication, sampling bias, and multi-scale model selection: A case study on snow leopard (Panthera uncia) in western China. Type Journal Article
  Year 2020 Publication Ecology and Evolution Abbreviated Journal  
  Volume Issue Pages 1-27  
  Keywords MaxEnt, meta-replication, multi-scale, Panthera uncia, sampling bias, scale selection, snow leopard, species distribution model  
  Abstract Replicated multiple scale species distribution models (SDMs)

have become increasingly important to identify the correct variables

determining species distribution and their influences on ecological

responses. This study explores multi-scale habitat relationships of the

snow leopard (Panthera uncia) in two study areas on the Qinghai–Tibetan

Plateau of western China. Our primary objectives were to evaluate the

degree to which snow leopard habitat relationships, expressed by

predictors, scales of response, and magnitude of effects, were

consistent across study areas or locally landcape-specific. We coupled

univariate scale optimization and the maximum entropy algorithm to

produce multivariate SDMs, inferring the relative suitability for the

species by ensembling top performing models. We optimized the SDMs based

on average omission rate across the top models and ensembles’ overlap

with a simulated reference model. Comparison of SDMs in the two study

areas highlighted landscape-specific responses to limiting factors.

These were dependent on the effects of the hydrological network,

anthropogenic features, topographic complexity, and the heterogeneity of

the landcover patch mosaic. Overall, even accounting for specific local

differences, we found general landscape attributes associated with snow

leopard ecological requirements, consisting of a positive association

with uplands and ridges, aggregated low-contrast landscapes, and large

extents of grassy and herbaceous vegetation. As a means to evaluate the

performance of two bias correction methods, we explored their effects on

three datasets showing a range of bias intensities. The performance of

corrections depends on the bias intensity; however, density kernels

offered a reliable correction strategy under all circumstances. This

study reveals the multi-scale response of snow leopards to environmental

attributes and confirms the role of meta-replicated study designs for

the identification of spatially varying limiting factors. Furthermore,

this study makes important contributions to the ongoing discussion about

the best approaches for sampling bias correction.
 
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  Call Number Serial 1616  
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Author Alexander, J. S., Shi, K., Tallents, L. A., Riordan, P. url  doi
  Title (up) On the high trail: examining determinants of site use by the Endangered snow leopard Panthera uncia in Qilianshan, China Type Journal Article
  Year 2015 Publication Oryx Abbreviated Journal  
  Volume Issue Fauna & Flora International Pages 1-8  
  Keywords Camera Trap, China, Detection Probability, Occupancy Modelling, Panthera Uncia, Site use, Snow Leopard  
  Abstract Abstract There is a need for simple and robust techniques for assessment and monitoring of populations of the Endangered snow leopard Panthera uncia to inform the de- velopment of action plans for snow leopard conservation. We explored the use of occupancy modelling to evaluate the influence of environmental and anthropogenic features on snow leopard site-use patterns. We conducted a camera trap survey across  km in Gansu Province, China, and used data from  camera traps to estimate probabilities of site use and detection using the single season occupancy model. We assessed the influence of three covariates on site use by snow leopards: elevation, the presence of blue sheep Pseudois nayaur and the presence of human disturb- ance (distance to roads). We recorded  captures of snow leopards over , trap-days, representing a mean capture success of . captures per  trap-days. Elevation had the strongest influence on site use, with the probability of site use increasing with altitude, whereas the influence of presence of prey and distance to roads was relatively weak. Our findings indicate the need for practical and robust tech- niques to appraise determinants of site use by snow leo- pards, especially in the context of the limited resources available for such work.  
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  Call Number SLN @ rakhee @ Serial 1433  
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Author Alexander, J., S., Gopalaswamy, A., M., Shi, K., Hughes, J., Riordan, P. url  doi
  Title (up) Patterns of Snow Leopard Site Use in an Increasingly Human-Dominated Landscape Type Journal Article
  Year 2016 Publication PLoS ONE Abbreviated Journal  
  Volume Issue Pages 1-15  
  Keywords  
  Abstract Human population growth and concomitant increases in demand for natural resources pose threats to many wildlife populations. The landscapes used by the endangered snow leopard (Panthera uncia) and their prey is increasingly subject to major changes in land use. We aimed to assess the influence of 1) key human activities, as indicated by the presence of mining and livestock herding, and 2) the presence of a key prey species, the blue sheep (Pseudois nayaur), on probability of snow leopard site use across the landscape. In Gansu Province, China, we conducted sign surveys in 49 grid cells, each of 16 km2 in size, within a larger area of 3392 km2. We analysed the data using likelihood-based habitat occupancy models that explicitly account for imperfect detection and spatial auto-correlation between survey transect segments. The model-averaged estimate of snow leopard occupancy was high [0.75 (SE 0.10)], but only marginally higher than the naïve estimate (0.67). Snow leop- ard segment-level probability of detection, given occupancy on a 500 m spatial replicate, was also high [0.68 (SE 0.08)]. Prey presence was the main determinant of snow leopard site use, while human disturbances, in the form of mining and herding, had low predictive power. These findings suggest that snow leopards continue to use areas very close to such disturbances, as long as there is sufficient prey. Improved knowledge about the effect of human activity on large carnivores, which require large areas and intact prey populations, is urgently needed for conservation planning at the local and global levels. We highlight a number of methodological considerations that should guide the design of such research.  
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  Call Number SLN @ rakhee @ Serial 1440  
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Author Shi, K.; Jun, Z.F.S.; Zhigang, D.; Riordan, P.; MacDonald, D. url 
  Title (up) Reconfirmation of snow leopards in Taxkurgan Nature Reserve, Xinjiang, China Type Journal Article
  Year 2009 Publication Oryx Abbreviated Journal  
  Volume 43 Issue 2 Pages 169-170  
  Keywords administration; Beijing; China; conservation; global; habitat; management; nature; presence; province; range; research; reserve; snow-leopard; snow-leopards; snow leopard; snow leopards; species; uncia; wildlife; Xinjiang  
  Abstract China may hold a greater proportion of the global snow leopard Panthera uncia population than any other country, with the area of good quality suitable habitat, estimated at nearly 300,000 km2, comprising .50% of that available across the species' entire range. We can now reconfirm the presence of snow leopard in the Taxkurgan area of Xinjiang Province in north-west China after a period of 20 years.  
  Address  
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  Publisher Fauna & Flora International Place of Publication United Kingdom Editor  
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  Notes SHI KUN Institute of Wildlife Conservation and Management, Beijing Forestry University, China ZHU FUDE SHI JUN and DAI ZHIGANG Xinjiang Forestry Administration, China PHILIP RIORDAN and DAVID MACDONALD Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Tubney House, Abingdon Road, Tubney, Abingdon, OX13 5QL, UK. E-mail philip.riordan@zoo.ox.ac.uk Approved no  
  Call Number SLN @ rana @ 1056 Serial 884  
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Author Riordan, P. url 
  Title (up) Unsupervised recognition of individual tigers and snow leopards from their footprints Type Miscellaneous
  Year 1998 Publication Animal Conservation Abbreviated Journal  
  Volume 1 Issue Pages 253-262  
  Keywords captive; panthera tigris; panthera uncia; snow leopard; techniques; tiger  
  Abstract This study presents the testing of two unsupervised classification methods for their ability to accurately identify unknown individual tigers, Panthera tigris, and snow leopards, Panthera uncia, from their footprints. A neural-network based method, the Kohonen self-organizing map (SOM), and a Bayesian method, AutoClass, were assessed using hind footprints taken from captive animals under standardized conditions. AutoClass successfully discriminated individuals of both species from their footprints. Classification accuracy was greatest for tigers, with more misclassification of individuals occurring for snow leopards. Examination of variable influence on class formations failed to identify consistently influential measurements for either species. The self-organizing map did not provide accurate classification of individuals for either species. Results were not substantially improved by altering map dimensions nor by using principal components derived from the original data. The interpretation of resulting classifications and the importance of using such techniques in the study of wild animal populations are discussed. The need for further testing in the field is highlighted.  
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  Call Number SLN @ rana @ 896 Serial 823  
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