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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.
Bangjie, T., & Bingxing, Q. (1994). The Status and Problems of Snow Leopards in Captivity in China. In J.L.Fox, & D.Jizeng (Eds.), (pp. 149–156). Usa: Islt.
Durbach, I., Borchers, D., Sutherland, C., Sharma, K. (2020). Fast, flexible alternatives to regular grid designs for spatial
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.
Harris, R. B. (1994). A note on snow leopards and local people in Nangqian County, Southern Qinghai Province. In J.L.Fox, & D. Jizeng (Eds.), (pp. 79–84). Usa: Islt.
Henschel, P., & Ray, J. (2003). Leopards in African Rainforests: Survey and Monitoring Techniques (Wildlife Conservation Society, Ed.).
Abstract: Monitoring Techniques Forest leopards have never been systematically surveyed in African forests, in spite of their potentially vital ecological role as the sole large mammalian predators in these systems. Because leopards are rarely seen in this habitat, and are difficult to survey using the most common techniques for assessing relative abundances of forest mammals, baseline knowledge of leopard ecology and responses to human disturbance in African forests remain largely unknown. This technical handbook sums up the experience gained during a two-year study of leopards by Philipp Henschel in the Lop‚ Reserve in Gabon, Central Africa, in 2001/2002, supplemented by additional experience from carnivore studies conducted by Justina Ray in southwestern Central African Republic and eastern Congo (Zaire) . The main focus of this effort has been to develop a protocol that can be used by fieldworkers across west and central Africa to estimate leopard densities in various forest types. In developing this manual, Henschel tested several indirect methods to assess leopard numbers in both logged and unlogged forests, with the main effort devoted to testing remote photography survey methods developed for tigers by Karanth (e.g., Karanth 1995, Karanth & Nichols 1998; 2000; 2002), and modifying them for the specific conditions characterizing African forest environments. This handbook summarizes the results of the field testing, and provides recommendations for techniques to assess leopard presence/absence, relative abundance, and densities in African forest sites. We briefly review the suitability of various methods for different study objectives and go into particular detail on remote photography survey methodology, adapting previously developed methods and sampling considerations specifically to the African forest environment. Finally, we briefly discuss how camera trapping may be used as a tool to survey other forest mammals. Developing a survey protocol for African leopards is a necessary first step towards a regional assessment and priority setting exercise targeted at forest leopards, similar to those carried out on large carnivores in Asian and South American forests.
Hussain, I. (1999). Conserving Biodiversity through Institutional Diversity: Concept Paper.
Jack, R. (2008). DNA Testing and GPS positioning of snow leopard (Panthera uncia) genetic material in the Khunjerab National Park Northern Areas, Pakistan.
Abstract: The protection of Snow Leopards in the remote and economically disadvantaged Northern Areas of Pakistan needs local people equipped with the skills to gather and present information on the number and range of individual animals in their area. It is important for the success of a conservation campaign that the people living in the area are engaged in the conservation process. Snow Leopards are elusive and range through inhospitable terrain so direct study is difficult. Consequently the major goals for this project were twofold, to gather information on snow leopard distribution in this area and to train local university students and conservation management professionals in the techniques used for locating snow leopards without the need to capture or even see the animals. This project pioneered the use of DNA testing of field samples collected in Pakistan to determine the distribution of snow leopards and to attempt to identify individuals. These were collected in and around that country's most northerly national park, the Kunjurab National Park, which sits on the Pakistan China border. Though the Northern Areas is not a well developed part of Pakistan, it does possess a number of institutions that can work together to strengthen snow leopard conservation. The first of these is a newly established University with students ready to be trained in the skills needed. Secondly WWF-Pakistan has an office in the main town and a state of the art GIS laboratory in Lahore and already works closely with the Forest Department who manage the national park. All three institutions worked together in this project with WWF providing GIS expertise, the FD rangers, and the university students carrying out the laboratory work. In addition in the course of the project the University of the Punjab in Lahore also joined the effort, providing laboratory facilities for the students. As a result of this project maps have been produced showing the location of snow leopards in
two areas. Preliminary DNA evidence indicates that there is more than one animal in this
relatively small area, but the greatest achievement of this project is the training and
experience gained by the local students. For one student this has been life changing. Due to
the opportunities provided by this study the student, Nelofar gained significant scientific
training and as a consequence she is now working as a lecturer and research officer for the
Center for Integrated Mountain Research, New Campus University of the Punjab, Lahore
Jackson, R., Ahlborn, G., & Shah, K. B. (1990). Capture and Immobilization of wild snow leopards. Int.Ped.Book of Snow Leopards, 6, 93–102.
Jackson, R., Roe, J., Wangchuk, R., & Hunter, D. (2006). Estimating Snow Leopard Population Abundance Using Photography and Capture-Recapture Techniques (Vol. 34).
Abstract: Conservation and management of snow leopards (Uncia uncial) has largely relied on anecdotal evidence and presence-absence data due to their cryptic nature and the difficult terrain they inhabit. These methods generally lack the scientific rigor necessary to accurately estimate population size and monitor trends. We evaluated the use of photography in capture-mark-recapture (CMR) techniques for estimating snow leopard population abundance and density within Hemis National Park, Ladakh, India. We placed infrared camera traps along actively used travel paths, scent-sprayed rocks, and scrape sites within 16-30 kmý sampling grids in successive winters during January and March 2003-2004. We used head-on, oblique, and side-view camera configurations to obtain snow leopard photographs at varying body orientations. We calculated snow leopard abundance estimates using the program CAPTURE. We obtained a total of 66 and 49 snow leopard captures resulting in 8.91 and 5.63 individuals per 100 trap nights during 2003 and 2004, respectively. We identified snow leopards based on the distinct pelage patters located primarily on the forelimbs, flanks, and dorsal surface of the tail. Capture probabilities ranged from 0.33 to 0.67. Density estimates ranged from 8.49 (SE+0.22) individuals per 100 kmý in 2003 to 4.45 (SE+0.16) in 2004. We believe the density disparity between years is attributable to different trap density and placement rather than to an actual decline in population size. Our results suggest that photographic capture-mark-recapture sampling may be a useful tool for monitoring demographic patterns. However, we believe a larger sample size would be necessary for generating a statistically robust estimate of population density and abundance based on CMR models.
Jackson, R. M. (1996). Home Range, Movements and Habitat use of Snow Leopard (Uncia uncia) in Nepal. Ph.D. thesis, University of London, University of London.
Abstract: Home ranges for five radio-tagged snow leopards (Uncia uncia) inhabiting prime habitat in Nepal Himalaya varied in size from 11-37 km2. These solitary felids were crepuscular in activity, and although highly mobile, nearly 90% of all consecutive day movements involved a straight line distance of 2km or less. No seasonal difference in daily movement or home range boundry was detected. While home ranges overlapped substancially, use of common core spaces was temporally seperated, with tagged animals being located 1.9 km or more apart during the smae day. Spatial analysis indicated that 47-55% of use occured within only 6-15% of total home area. The snow leopards shared a common core use area, which was located at a major stream confuence in an area where topography, habitat and prey abundance appeared to be more favorable. A young female used her core area least, a female with two cubs to the greatest extent. the core area was marked significantly more with scrapes, Faeces and other sighn than non-core sites, suggesting that social marking plays an important role in spacing individuals. Snow leopards showed a strong preference for bedding in steep, rocky or broken terrain, on or close to a natural vegetation or landform edge. linear landform features, such as a cliff or major ridgeline, were preferred for travelling and day time resting. This behavior would tend to place a snow leopard close to its preferred prey, blue sheep (Psuedois nayaur), which uses the same habitat at night. Marking was concetrated along commonly travelled routes, particularly river bluffs, cliff ledges and well defined ridgelines bordering stream confluences--features that were most abundant within the core area. Such marking may facilitate mutual avoidance, help maintain the species' solitary social structure, and also enable a relatively high density of snow leopard, especially within high-quality habitat.