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McCarthy, K., Fuller, T., Ming, M., McCarthy, T., Waits, L., & Jumabaev, K. (2008). Assessing Estimators of Snow Leopard Abundance (Vol. 72).
Abstract: The secretive nature of snow leopards (Uncia uncia) makes them difficult to monitor, yet conservation efforts require accurate and precise methods to estimate abundance. We assessed accuracy of Snow Leopard Information Management System (SLIMS) sign surveys by comparing them with 4 methods for estimating snow leopard abundance: predator:prey biomass ratios, capture-recapture density estimation, photo-capture rate, and individual identification through genetic analysis. We recorded snow leopard sign during standardized surveys in the SaryChat Zapovednik, the Jangart hunting reserve, and the Tomur Strictly Protected Area, in the Tien Shan Mountains of Kyrgyzstan and China. During June-December 2005, adjusted sign averaged 46.3 (SaryChat), 94.6 (Jangart), and 150.8 (Tomur) occurrences/km. We used
counts of ibex (Capra ibex) and argali (Ovis ammon) to estimate available prey biomass and subsequent potential snow leopard densities of 8.7 (SaryChat), 1.0 (Jangart), and 1.1 (Tomur) snow leopards/100 km2. Photo capture-recapture density estimates were 0.15 (n = 1 identified individual/1 photo), 0.87 (n = 4/13), and 0.74 (n = 5/6) individuals/100 km2 in SaryChat, Jangart, and Tomur, respectively. Photo-capture rates
(photos/100 trap-nights) were 0.09 (SaryChat), 0.93 (Jangart), and 2.37 (Tomur). Genetic analysis of snow leopard fecal samples provided minimum population sizes of 3 (SaryChat), 5 (Jangart), and 9 (Tomur) snow leopards. These results suggest SLIMS sign surveys may be affected by observer bias and environmental variance. However, when such bias and variation are accounted for, sign surveys indicate relative abundances similar to photo rates and genetic individual identification results. Density or abundance estimates based on capture-recapture or ungulate biomass did not agree with other indices of abundance. Confidence in estimated densities, or even detection of significant changes in abundance of snow leopard, will require more effort and better documentation.
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Ming, M., Munkhtsog, B., Xu, F., Turghan, M., Yin, S. -jing, & Wei, S. - D. (2005). Markings as Indicator of Snow Leopard in Field Survey, in Xinjiang.
Abstract: The Snow Leopard (Uncia uncia) was a very rare species in China. The survey on the markings of Snow Leopard in Ahay and Tianshan Mountains is the major activity of the Project of Snow Leopard in Xinjiang, supported by International Snow Leopard Trust(ISLT)and Xinjiang Conservation Fund(XCF). During the field work from Sep to Nov 2004 the Xinjiang Snow Leopard Group(XSLG) set 67 transects of a total length of 47 776 m with mean transect length is 7 1 3 m at 9 locations.Total of 1 l 8 markings of Snow Leopards were found in 27 transects the mean density is 247km. The markings of Snow Leopard included the pug marks or footprints, scrapes, feces, bloodstain, scent spray, urine, hair or fur, claw rake, remains of prey corpse, sleep site, roar and others. From the quantity and locations of marks the XSLG got the information on habitat selection distribution region and relative abundance of the Snow Leopard in the study areas. The survey also provided knowledge on distribution and abundance of major prey potential conservation problems and human attitudes to Snow Leopards by taking 200 questionnaires in the study areas.
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Oli, M. (1994). Snow leopards and blue sheep in Nepal: Densities and predator: Prey ratio (Vol. 75).
Abstract: I studied snow leopards (Panthera uncia) and blue sheep (Pseudois nayaur) in Manang District, Annapurna Conservation Area, Nepal, to estimate numbers and analyze predatorprey interactions. Five to seven adult leopards used the 105-km2 study area, a density of 4.8 to 6.7 leopards/100 km2. Density of blue sheep was 6.6-10.2 sheep/km2, and biomass density was 304 kg/km2. Estimated relative biomass consumed by snow leopards suggested that blue sheep were the most important prey; marmots (Marmota himalayana) also contributed significantly to the diet of snow leopards. Snow leopards in Manang were estimated to harvest 9-20% of total biomass and 11-24% of total number of blue sheep annually. Snow leopard :blue sheep ratio was 1 :1 14-1 :159 on a weight basis, which was considered sustainable given the importance of small mammals in the leopard's diet and the absence of other competing predators.
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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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Oli, M. K. (1997). Winter home range of snow leopards in Nepal. Mammalia, 61(3), 355–360.
Abstract: Because of their low densities, sparse distribution, elusive behavior, and the precipitous habitat they occupy, snow leopards (Uncia uncia) have been the subject of limited study. This study contributes to that limited database with an investigation of the winter home range of 3 radio-collared snow leopards (2 females and 1 male) in the Annapurna Conservation Area, Nepal. Winter home ranges varied from 13.9-22.3 km2 (x = 19.1). Home ranges overlapped extensively within and between sexes, and an area of 8.1 km2 in the core study site was shared by all three leopards.
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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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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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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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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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