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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. |
Korablev, M. P., Poyarkov, A. D., Karnaukhov, A. S., Zvychaynaya, E. Y., Kuksin, A. N., Malykh, S. V., Istomov, S. V., Spitsyn, S. V., Aleksandrov, D. Y., Hernandez-Blanco, J. A., Munkhtsog, B., Munkhtogtokh, O., Putintsev, N. I., Vereshchagin, A. S., Becmurody, A., Afzunov, S., Rozhnov, V. V. (2021). Large-scale and fine-grain population structure and genetic diversity of snow leopards (Panthera uncia Schreber, 1776) from the northern and western parts of the range with an emphasis on the Russian population. Conservation Genetics, .
Abstract: The snow leopard (Panthera uncia Schreber, 1776) population in Russia and Mongolia is situated at the northern edge of the range, where instability of ecological conditions and of prey availability may serve as prerequisites for demographic instability and, consequently, for reducing the genetic diversity. Moreover, this northern area of the species distribution is connected with the western and central parts by only a few small fragments of potential habitats in the Tian-Shan spurs in China and Kazakhstan. Given this structure of the range, the restriction of gene flow between the northern and other regions of snow leopard distribution can be expected. Under these conditions, data on population genetics would be extremely important for assessment of genetic diversity, population structure and gene flow both at regional and large-scale level. To investigate large-scale and fine-grain population structure and levels of genetic diversity we analyzed 108 snow leopards identified from noninvasively collected scat samples from Russia and Mongolia (the northern part of the range) as well as from Kyrgyzstan and Tajikistan (the western part of the range) using panel of eight polymorphic microsatellites. We found low to moderate levels of genetic diversity in the studied populations. Among local habitats, the highest heterozygosity and allelic richness were recorded in Kyrgyzstan (He = 0.66 ± 0.03, Ho = 0.70 ± 0.04, Ar = 3.17) whereas the lowest diversity was found in a periphery subpopulation in Buryatia Republic of Russia (He = 0.41 ± 0.12, Ho = 0.29 ± 0.05, Ar = 2.33). In general, snow leopards from the western range exhibit greater genetic diversity (He = 0.68 ± 0.04, Ho = 0.66 ± 0.03, Ar = 4.95) compared to those from the northern range (He = 0.60 ± 0.06, Ho = 0.49 ± 0.02, Ar = 4.45). In addition, we have identified signs of fragmentation in the northern habitat, which have led to significant genetic divergence between subpopulations in Russia. Multiple analyses of genetic structure support considerable genetic differentiation between the northern and western range parts, which may testify to subspecies subdivision of snow leopards from these regions. The observed patterns of genetic structure are evidence for delineation of several management units within the studied populations, requiring individual approaches for conservation initiatives, particularly related to translocation events. The causes for the revealed patterns of genetic structure and levels of genetic diversity are discussed.
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Janecka, J.E., Jackson, R., Yuquang, Z., Diqiang, L., Munkhtsog, B., et al. (2008). Population monitoring of snow leopards using noninvasive collection of scat samples: a pilot study (Vol. 11).
Abstract: The endangered snow leopard Panthera uncia occurs in rugged, high-altitude regions of Central Asia. However, information on the status of this felid is limited in many areas. We conducted a pilot study to optimize molecular markers for the analysis of snow leopard scat samples and to examine the feasibility of using noninvasive genetic methods for monitoring this felid. We designed snow leopard-specific primers for seven microsatellite loci that amplified shorter segments and avoided flanking sequences shared with repetitive elements. By redesigning primers we maximized genotyping success and minimized genotyping errors. In addition, we tested a Y chromosome-marker for sex identification and designed a panel of mitochondrial DNA primers for examining genetic diversity of snow leopards using scat samples. We collected scats believed to be from snow leopards in three separate geographic regions including north-western India, central China and southern Mongolia. We observed snow leopard scats in all three sites despite only brief 2-day surveys in each area. There was a high rate of species misidentification in the field with up to 54% of snow leopard scats misidentified as red fox. The high rate of field misidentification suggests sign surveys incorporating scat likely overestimate snow leopard abundance. The highest ratio of snow leopard scats was observed in Ladakh (India) and South Gobi (Mongolia), where four and five snow leopards were detected, respectively. Our findings describe a species-specific molecular panel for analysis of snow leopard scats, and highlight the efficacy of noninvasive genetic surveys for monitoring snow leopards. These methods enable large-scale noninvasive studies that will provide information critical for conservation of snow leopards.
Keywords: snow leopard; genetics; scat; noninvasive; survey.
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Jiang, Z. (2005). Snow leopards in the Dulan International Hunting Ground, Qinghai, China.
Abstract: From March to May, 2006œªwe conducted extensive snow leopard surveys in the Burhanbuda Mountain Kunlun Mountains, Qinghai Province, China. 32 linear transect of 5~15 km each, which running through each vegetation type, were surveyed within the study area. A total of 72 traces of snow leopard were found along 4 transects (12.5% of total transects). The traces included pug marks or footprints, scrapes and urine marks. We estimated the average density of wild ungulates in the region was 2.88ñ0.35 individuals km-2(n=29). We emplaced 16 auto2 trigger cameras in different environments and eight photos of snow leopard were shot by four cameras and the capture rate of snow leopard was 71.4%. The minimum snow leopard population size in the Burhanbuda Mountain was two, because two snow leopards were phototrapped by different cameras at almost same time. Simultaneously, the cameras also shot 63 photos of other wild animals, including five photos are unidentified wild animals, and 20 photos of livestock. We evaluated the human attitudes towards snow leopard by interviewing with 27 Tibetan householders of 30 householders live in the study area. We propose to establish a nature reserve for protecting and managing snow leopards in the region. Snow leopard (Uncia uncia) is considered as a unique species because it lives above the snow line, it is endemic to alpines in Central Asia, inhabiting in 12 countries across Central Asia (Fox, 1992). Snow leopard ranges in alpine areas in Qinghai, Xinjiang, Inner Mongolia, Tibet, Gansu and Sichuan in western China (Liao, 1985, 1986; Zhou, 1987; Ma et al., 2002; Jiang & Xu, 2006). The total population and habitat of snow leopards in China are estimated to be 2,000~2,500 individuals and 1,824,316 km2, only 5% of which is under the protection of nature reserves. The cat's current range is fragmented (Zou & Zheng, 2003). Due to strong human persecutions, populations of snow leopards decreased significantly since the end of the 20th century. Thus, the
snow leopards are under the protection of international and domestic laws. From March to May, 2006, we conducted two field surveys in Zhiyu Village, Dulan County in Burhanbuda Mountain, Kunlun Mountains, China to determine the population, distribution and survival status of snow leopards in the area. The aim of the study was to provide ecologic data for snow leopard conservation. Keywords: snow; snow leopards; snow leopard; snow-leopards; snow-leopard; leopards; leopard; International; hunting; Qinghai; China; project; international snow leopard trust; International-Snow-Leopard-Trust; trust; program; surveys; survey; mountains; mountain; province; transect; study; area; transects; pug; pug marks; pug-marks; marks; scrapes; scrape; density; densities; wild; ungulates; ungulate; region; camera; environment; photo; capture; population; population size; population-size; Animals; Animal; 20; livestock; Human; attitudes; attitude; tibetan; 30; nature; reserve; uncia; Uncia uncia; Uncia-uncia; species; snow line; snow-line; endemic; alpine; central; Central Asia; asia; countries; country; fox; range; areas; Xinjiang; inner; Inner-Mongolia; Mongolia; Tibet; gansu; Sichuan; habitat; protection; nature reserves; reserves; cat; populations; domestic; laws; law; field; field surveys; field survey; field-surveys; field-survey; Kunlun; distribution; survival; status; Data; conservation
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Khan, A. (2004). Snow Leopard Occurrence in Mankial Valley, Swat: Final report.
Abstract: Mankial is a sub-valley of the Swat Kohistan. Temperate ecosystem of the valley is intact to a greater extent, which provides habitat to a variety of species of plants, animals and birds. Snow leopard is reported from the valley. To confirm its occurrence, the HUJRA (Holistic Understanding for Justified Research and Action), conducted the study titled “Snow Leopard Survey in Mankial Valley, district Swat, NWFP”. The author provided technical support, while ISLT (The International Snow Leopard Trust) funded the project under its small grants program. The World Wide Fund for Nature-Pakistan (WWF-Pakistan) and the Mankial Community Organization (MCO) facilitated surveys under the project. Surveys revealed that Snow leopard visits parts of the Mankial valley in winter months. Information from the local community shows that Snow leopard remains in the Serai (an off-shoot of the Mankial Valley) from early winter to early spring. Intensive surveys of the prime snow leopard winter habitat in the valley found several snow leopard signs including pugmarks, feces, and scrapes. The study also found occurrence of prey species through indirect evidence though. However, information from the local community confirmed that in the recent past there was a good population of markhor in the valley, which is now reduced to less than 50, mostly due to hunting and habitat disturbance. Hunting is part of the local culture and lifestyle. During winter months hunting pressure is low, as most of the local community migrates to warmer plain areas than Mankial Valley. However, those who live in the area lop oak branches for feeding their livestock and cut trees for burning, in addition to hunting prey species of snow leopard. This has resulted in stunted oak vegetation in most of the lower reaches of the valley and decline of the markhor population.
Keywords: snow; snow leopard; snow-leopard; leopard; valley; Report; project; International; international snow leopard trust; International-Snow-Leopard-Trust; trust; program; ecosystem; habitat; species; plants; plant; Animals; Animal; birds; research; action; study; survey; Support; Islt; community; Organization; surveys; winter; information; local; sign; pugmarks; feces; scrapes; scrape; prey; prey species; prey-species; recent; population; markhor; hunting; Culture; Pressure; areas; area; feeding; livestock; burning; decline
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Khatiwada, J. R., Chalise, M. K., & Kyes, R. (2007). Survey of Snow Leopard (Uncia uncia) and Blue Sheep (Pseudois nayaur) populations in the Kangchenjunga Conservation Area (KCA), Nepal. Final report.
Abstract: This study was carried out in the Kangchenjunga Conservation Area (KCA), Eastern Nepal from Feb – Nov 2007. We used the Snow Leopard Information Management System, SLIMS (second order survey technique) to determine the relative abundance of snow leopard in the upper part of KCA. Altogether, 36 transects (total length of 15.21 km) were laid down in the major three blocks of KCA. 104 Signs (77 scrapes, 20 feces, 2 Scent mark, 3 Pugmarks and 2 hairs) were recorded. Fixed-point count method was applied for blue sheep from appropriate vantage points. We counted total individual in each herd using 8x42 binocular and 15-60x spotting scope. A total of 43 herds and 1102 individuals were observed in the area. The standard SLIMS questionnaire was conducted to find out relevant information on livestock depredation patterns. Out of 35 households surveyed in KCA, 48% of herders lost livestock due to snow leopards. A total of 21 animals were reportedly lost due to snow leopards from August to September 2007.
Keywords: survey; snow; snow leopard; snow-leopard; leopard; uncia; Uncia uncia; Uncia-uncia; blue; blue sheep; blue-sheep; sheep; Pseudois; pseudois nayaur; Pseudois-nayaur; nayaur; populations; population; conservation; area; Nepal; Report; study; information; management; system; Slims; relative abundance; abundance; transects; transect; length; sign; scrapes; scrape; 20; feces; scent; pugmarks; hairs; Hair; using; livestock; livestock depredation; livestock-depredation; depredation; patterns; herders; herder; snow leopards; snow-leopards; leopards; Animals; Animal
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Jackson, R., & Hunter, D. O. (1995). Snow Leopard Survey and Conservation Handbook (2nd Edition). ISLT and National Biological Survey. |
Jackson, R. (1992). SSC Plan for Snow Leopard.
Keywords: physiology; status; distribution; description; behavior; reproduction; mating; breeding; vocalization; gestation; biology; habitat; scrapes; sprays; scat; feces; longevity; homerange; home-range; prey; diet; Cites; Iunc; parks; preserves; reserves; refuge; protected-areas; movements; activity; livestock; herders; depredation; conflict; trade; poaching; hunting; research; captivity; management; zoos; Slims; surveys; transects; browse; home range; home; range; protected area; protected areas; protected; area; areas; 3920; plan; snow; snow leopard; snow-leopard; leopard
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Kyes, R., & Chalise, M. K. (2005). Assessing the Status of the Snow Leopard Population in Langtang National Park, Nepal.
Abstract: This project is part of an ongoing snow leopard study established in 2003 with support from the ISLT. The study involves a multifaceted approach designed to provide important baseline data on the status of the snow leopard population in Langtang National Park (LNP), Nepal and to generate long-term support and commitment to the conservation of snow leopards in the park. The specific aims include: 1) conducting a population survey of the snow leopards in LNP, focusing on distribution and abundance; 2) assessing the status of prey species populations in the park; and 3) providing educational outreach programs on snow leopard conservation for local school children (K-8) living in the park. During the 2004 study period, snow leopard signs were observed (including pugmarks and scats) although somewhat fewer than in 2003. Similarly, the average herd size of the snow leopards' primary prey species in LNP (the Himalayan thar) was a bit lower than in 2003. There is speculation that the thar populations and the snow leopards may be moving to more remotes areas of the park perhaps in response to increasing pressure from domestic livestock grazing. This possibility is being addressed during the 2005 study period.
Keywords: status; snow; snow leopard; snow-leopard; leopard; population; Langtang; national; national park; National-park; park; Nepal; project; International; international snow leopard trust; International-Snow-Leopard-Trust; trust; program; biodiversity; research; study; Support; Islt; approach; Data; conservation; snow leopards; snow-leopards; leopards; survey; distribution; abundance; prey; prey species; prey-species; species; populations; programs; local; sign; pugmarks; scats; scat; primary; Himalayan; areas; area; Response; Pressure; domestic; domestic livestock; livestock; grazing
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Yang, Q. (1992). Further study on the geographical distribution and conservation of snow leopard in Qinghai, P.R. China. |