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Durbach, I., Borchers, D., Sutherland, C., Sharma, K. (2020). Fast, flexible alternatives to regular grid designs for spatial
capture–recapture..
Abstract: Spatial capture–recapture (SCR) methods use the location of
detectors (camera traps, hair snares and live-capture traps) and the
locations at which animals were detected (their spatial capture
histories) to estimate animal density. Despite the often large expense
and effort involved in placing detectors in a landscape, there has been
relatively little work on how detectors should be located. A natural
criterion is to place traps so as to maximize the precision of density
estimators, but the lack of a closed-form expression for precision has
made optimizing this criterion computationally demanding. 2. Recent
results by Efford and Boulanger (2019) show that precision can be well
approximated by a function of the expected number of detected
individuals and expected number of recapture events, both of which can
be evaluated at low computational cost. We use these results to develop
a method for obtaining survey designs that optimize this approximate
precision for SCR studies using count or binary proximity detectors, or
multi-catch traps. 3. We show how the basic design protocol can be
extended to incorporate spatially varying distributions of activity
centres and animal detectability. We illustrate our approach by
simulating from a camera trap study of snow leopards in Mongolia and
comparing estimates from our designs to those generated by regular or
optimized grid designs. Optimizing detector placement increased the
number of detected individuals and recaptures, but this did not always
lead to more precise density estimators due to less precise estimation
of the effective sampling area. In most cases, the precision of density
estimators was comparable to that obtained with grid designs, with
improvement in some scenarios where approximate CV(¬D) < 20% and density
varied spatially. 4. Designs generated using our approach are
transparent and statistically grounded. They can be produced for survey
regions of any shape, adapt to known information about animal density
and detectability, and are potentially easier and less costly to
implement. We recommend their use as good, flexible candidate designs
for SCR surveys when reasonable knowledge of model parameters exists. We
provide software for researchers to construct their own designs, in the
form of updates to design functions in the r package oSCR.
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Augugliaro, C., Paniccia, C., Janchivlamdan, C., Monti, I. E., Boldbaatar, T., Munkhtsog, B. (2019). Mammal inventory in the Mongolian Gobi, with the southeasternmost documented record of the Snow Leopard, Panthera uncia (Schreber, 1775), in the country. Check List, 15(4), 575–578.
Abstract: Studies on mammal diversity and distribution are an important source to develop conservation and management strategies.
The area located in southern Mongolia, encompassing the Alashan Plateau Semi-Desert and the Eastern Gobi Desert-Steppe ecoregions, is considered strategic for the conservation of threatened species. We surveyed the non-volant mammals in the Small Gobi-A Strictly Protected Area (SPA) and its surroundings, by using camera trapping, live trapping, and occasional sightings. We recorded 18 mammal species belonging to 9 families and 6 orders. Among them, 4 are globally threatened or near-threatened, 2 are included in the CITES Appendix I, and 2 are listed in the Appendix II. Moreover, we provide the southeasternmost record for the Snow Leopard (Panthera uncia) in Mongolia, supported by photographic evidence. Our study highlights the importance of this protected area to preserve rare, threatened, and elusive species.
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Suryawanshi, K. R., Khanyari, M., Sharma, K., Lkhagvajav, P., Mishra, C. (2019). Sampling bias in snow leopard population estimation studies. Population Eccology, , 1–9.
Abstract: Accurate assessments of the status of threatened species and their conservation
planning require reliable estimation of their global populations and robust monitoring
of local population trends. We assessed the adequacy and suitability of studies
in reliably estimating the global snow leopard (Panthera uncia) population. We
compiled a dataset of all the peer-reviewed published literature on snow leopard
population estimation. Metadata analysis showed estimates of snow leopard density
to be a negative exponential function of area, suggesting that study areas have generally
been too small for accurate density estimation, and sampling has often been
biased towards the best habitats. Published studies are restricted to six of the
12 range countries, covering only 0.3�0.9% of the presumed global range of the
species. Re-sampling of camera trap data from a relatively large study site
(c.1684 km2) showed that small-sized study areas together with a bias towards
good quality habitats in existing studies may have overestimated densities by up to
five times. We conclude that current information is biased and inadequate for generating
a reliable global population estimate of snow leopards. To develop a rigorous
and useful baseline and to avoid pitfalls, there is an urgent need for
(a) refinement of sampling and analytical protocols for population estimation of
snow leopards (b) agreement and coordinated use of standardized sampling protocols
amongst researchers and governments across the range, and (c) sampling
larger and under-represented areas of the snow leopard's global range.
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Lama, R. P., Ghale, T. R., Suwal, M. K., Ranabhat, R., Regmi, G. R. (2018). First photographic evidence of Snow Leopard Panthera uncia (Mammalia: Carnivora: Felidae) outside current protected areas network in Nepal Himalaya. Journal of Threatened Taxa, , 12086–12090.
Abstract: The Snow Leopard Panthera uncia is a rare top predator of high-altitude ecosystems and insufficiently surveyed outside of protected areas in Nepal. We conducted a rapid camera-trapping survey to assess the presence of Snow Leopard in the Limi valley of Humla District. Three individuals were recorded in two camera locations offering the first photographic evidence of this elusive cat outside the protected area network of Nepal. In addition to Snow Leopard, the Blue Sheep Pseudois nayaur, Beech Marten Martes foina, Pika Ochotona spp. and different species of birds were also detected by camera-traps. More extensive surveys and monitoring are needed for reliably estimating the population size of Snow Leopard in the area. The most urgent needs are community-based conservation activities aimed at mitigating immediate threats of poaching, retaliatory killing, and rapid prey depletion to ensure the survival of this top predator in the Himalaya.
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Rovero, F., Augugliaro, C., Havmoller, R. W., Groff, C., Zimmerman, F., Oberosler, V., Tenan, S. (2018). Co-occurrence of snow leopard Panthera uncia, Siberian ibex Capra sibirica and livestock: potential relationships and effects. Oryx, , 1–7.
Abstract: Understanding the impact of livestock on native
wildlife is of increasing conservation relevance. For the
Vulnerable snow leopard Panthera uncia, wild prey reduction,
intensifying human�wildlife conflicts and retaliatory
killings are severe threats potentially exacerbated by the
presence of livestock. Elucidating patterns of co-occurrence
of snow leopards, wild ungulate prey, and livestock, can be
used to assess the compatibility of pastoralism with conservation.
We used camera trapping to study the interactions of
livestock, Siberian ibex Capra sibirica and snow leopards in
a national park in the Altai mountains, Mongolia. We obtained
 detections of wild mammals and  of domestic
ungulates, dogs and humans. Snow leopards and Siberian
ibex were recorded  and  times, respectively. Co-occurrence
modelling showed that livestock had a higher estimated
occupancy (.) than ibex, whose occupancy was
lower in the presence of livestock (.) than in its absence
(.�. depending on scenarios modelled). Snow leopard
occupancy did not appear to be affected by the presence of
livestock or ibex but the robustness of such inference was
limited by uncertainty around the estimates. Although our
sampling at presumed snow leopard passing sites may have
led to fewer ibex detections, results indicate that livestock
may displace wild ungulates, but may not directly affect
the occurrence of snow leopards. Snow leopards could still
be threatened by livestock, as overstocking can trigger
human�carnivore conflicts and hamper the conservation
of large carnivores. Further research is needed to assess
the generality and strength of our results.
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Sivolobov, R. (2017). ENDANGERED SPECIES OF KORYAKIA AND CHUKOTKA: IRBIS, TIGER AND THE IRKUYEM-BEAR.225–233.
Abstract: After 30 years of searching for the mysterious Beringian snow cat in vast space of Koryakia and Chukotka
one of the five cameras recorded finally this beast at night in September 2014. This is not so much a
sensation as a real scientific discovery, saying that the hearts of the snow leopard population resettlement are
not in 5000 km from the main range boundaries, but much closer. Where? � will show further studies.
In addition to the snow leopard in the North-Eastern Asia, it found two more endangered large
mammal species: the Amur tiger and the relict of the Ice Age � the Irkuyem-bear. Author has given these
animals his life and his article devoted to this topic.
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Kashkarov, E. (2017). THE SNOW LEOPARD OF KIRGIZIA: NATIONAL SHAME OR NATIONAL PRIDE.239–253.
Abstract: Article examines the problems existing in conservation of the snow leopard in Kirgizia after break-up of the
USSR. Unfortunate situation is common to most of the 14 countries in the snow leopard range, but seems
especially sharp to Kirgizia. Yet half of the century ago Kirgizia has had about 1.5 thousand of the snow
leopards, and today there remains no more than 1/10. In Soviet time Kirgizia was a global supplier of the
snow leopards for the zoo-export � to create a reserve number of endangered cats in captivity. Today, at
least half of the snow leopards in the Zoos of the world are individuals, caught in Kirgizia or their
descendants.
Since independence, Kirgizia has set new records. In Sarychat-Irtash reserve � the best for the snow
leopard in Central Asia, and probably in the whole range � this species was completely destroyed after 3
years of reserve opening... and 17 years later � revived... Situation comes presently back to the worst-case
scenario, and not only for the snow leopard. Author shows how work in this direction social and economic
levers, and what kind future he would like to see in Kirgizia, where he lived for 12 years and was at the
forefront of pioneering research of the snow leopard and its conservation.
Keywords: snow leopard, irbis, ibex, mountain sheep, conservation, range, reserve, monitoring, cameratrap, Sarychat, Kirgizia, Central Asia.
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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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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, J. S., Shi, K., Tallents, L. A., Riordan, P. (2015). On the high trail: examining determinants of site use by the Endangered snow leopard Panthera uncia in Qilianshan, China. Oryx, (Fauna & Flora International), 1–8.
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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