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Janjua, S., Peters, J. L., Weckworth, B., Abbas, F. I., Bahn, Volker, Johansson, O., Rooney, T.P. (2019). Improving our conservation genetic toolkit: ddRAD-seq for SNPs in snow leopards. Conservation Genetic Resource, .
Abstract: Snow leopards (Panthera uncia) are an enigmatic, high-altitude species whose challenging habitat, low population densities
and patchy distribution have presented challenges for scientists studying its biology, population structure, and genetics.
Molecular scatology brings a new hope for conservation efforts by providing valuable insights about snow leopards, including
their distribution, population densities, connectivity, habitat use, and population structure for assigning conservation units.
However, traditional amplification of microsatellites from non-invasive sources of DNA are accompanied by significant
genotyping errors due to low DNA yield and poor quality. These errors can lead to incorrect inferences in the number of
individuals and estimates of genetic diversity. Next generation technologies have revolutionized the depth of information
we can get from a species' genome. Here we used double digest restriction-site associated DNA sequencing (ddRAD-seq),
a well-established technique for studying non-model organisms, to develop a reference sequence library for snow leopards
using blood samples from five Mongolian individuals. Our final data set reveals 4504 loci with a median size range of 221 bp.
We identified 697 SNPs and low nucleotide diversity (0.00032) within these loci. However, the probability that two random
individuals will share identical genotypes is about 10-168. We developed probes for DNA capture using this sequence library
which can now be used for genotyping individuals from scat samples. Genetic data from ddRAD-seq will be invaluable for
conducting population and landscape scale studies that can inform snow leopard conservation strategies.
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Johansson, O., Kachel, S., Weckworth, B. (2022). Guidelines for Telemetry Studies on Snow Leopards. Animals, 12(1663), 1–12.
Abstract: Animal-borne tracking devices have generated a wealth of new knowledge, allowing us to better understand, manage and conserve species. Fitting such tracking devices requires that animals are captured and often chemically immobilized. Such procedures cause stress and involve the risk of injuries and loss of life even in healthy individuals. For telemetry studies to be justifiable, it is vital that capture operations are planned and executed in an efficient and ethical way. Project objectives must be clearly articulated to address well-defined knowledge gaps, and studies designed to maximize the probability of achieving those goals. We provide guidelines for how to plan, design, and implement telemetry studies with a special emphasis on snow leopards that are typically captured using foot snares. We also describe the necessary steps to ensure that captures are conducted safely, and with minimal stress to animals.
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Kachel, S., Bayrakcismith, R., Kubanychbekov, Z., Kulenbekov, R., McCarthy, T., Weckworth, B., Wirsing, A. (2022). Ungulate spatiotemporal responses to contrasting predation risk from wolves and snow leopards. Journal of Animal Ecology, , 1–16.
Abstract: 1. Spatial responses to risk from multiple predators can precipitate emergent consequences for prey (i.e. multiple-predator effects, MPEs) and mediate indirect interactions between predators. How prey navigate risk from multiple predators may therefore have important ramifications for understanding the propagation of predation-risk effects (PREs) through ecosystems.
2. The interaction of predator and prey traits has emerged as a potentially key driver of antipredator behaviour but remains underexplored in large vertebrate systems, particularly where sympatric prey share multiple predators. We sought to better generalize our understanding of how predators influence their ecosystems by considering how multiple sources of contingency drive prey distribution in a multi-predator–multi-prey system.
3. Specifically, we explored how two sympatric ungulates with different escape tactics—vertically agile, scrambling ibex Capra sibirica and sprinting argali Ovis ammon—responded to predation risk from shared predators with contrasting hunting modes—cursorial wolves Canis lupus and vertical-ambushing, stalking snow leopards Panthera uncia.
4. Contrasting risk posed by the two predators presented prey with clear trade-offs. Ibex selected for greater exposure to chronic long-term risk from snow leopards, and argali for wolves, in a nearly symmetrical manner that was predictable based on the compatibility of their respective traits. Yet, acute short-term risk from the same predator upended these long-term strategies, increasing each ungulates' exposure to risk from the alternate predator in a manner consistent with a scenario in which conflicting antipredator behaviours precipitate risk-enhancing MPEs and mediate predator facilitation. By contrast, reactive responses to wolves led ibex to reduce their exposure to risk from both predators—a risk-reducing MPE. Evidence of a similar reactive risk-reducing effect for argali vis-à-vis snow leopards was lacking.
5. Our results suggest that prey spatial responses and any resulting MPEs and prey-mediated interactions between predators are contingent on the interplay of hunting mode and escape tactics. Further investigation of interactions among various drivers of contingency in PREs will contribute to a more comprehensive understanding and improved forecasting of the ecological effects of predators.
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Li, J., McCarthy, T. M., Wang, H., Weckworth, B. V., Shaller, G. B., Mishra, C., Lu, Z., Beissinger, S. R. (2016). Climate refugia of snow leopards in High Asia. Biological Conservation, (203), 188–196.
Abstract: Rapidwarming in High Asia is threatening its unique ecosystemand endemic species, especially the endangered
snow leopard (Panthera uncia). Snow leopards inhabit the alpine zone between snow line and tree line, which
contracts and expands greatly during glacier-interglacial cycles. Here we assess impacts of climate change on
global snow leopard habitat from the last glacial maximum (LGM; 21 kyr ago) to the late 21st century. Based
on occurrence records of snow leopards collected across all snow leopard range countries from 1983 to 2015,
we built a snow leopard habitat model using the maximum entropy algorithm (MaxEnt 3.3.3k). Then we
projected this model into LGM, mid-Holocene and 2070. Analysis of snow leopard habitat map from LGM to
2070 indicates that three large patches of stable habitat have persisted from the LGM to present in the Altai,
Qilian, and Tian Shan-Pamir-Hindu Kush-Karakoram mountain ranges, and are projected to persist through the
late 21st century. These climatically suitable areas account for about 35% of the snow leopard's current extent,
are large enough to support viable populations, and should function as refugia for snow leopards to survive
through both cold and warm periods. Existence of these refugia is largely due to the unique mountain environment
in High Asia, which maintains a relatively constant arid or semi-arid climate. However, habitat loss leading
to fragmentation in the Himalaya and Hengduan Mountains, as well as increasing human activities, will present
conservation challenges for snow leopards and other sympatric species.
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Li, J., Weckworth, B. V., McCarthy, T. M., Liang, X., Liu, Y., Xing, R., Li, D., Zhang, Y., Xue, Y., Jackson, R., Xiao, L., Cheng, C., Li, S., Xu, F., Ma, M., Yang, X., Diao, K., Gao, Y., Song, D., Nowell, K., He, B., Li, Y., McCarthy, K., Paltsyn, M. Y., Sharma, K., Mishra, C., Schaller, G. B., Lu, Z., Beissinger, S. R. (2019). Defining priorities for global snow leopard conservation landscapes. Biological Conservation, 241(108387), 1–10.
Abstract: The snow leopard (Panthera uncia) is an apex predator on the Tibetan Plateau and in the surrounding mountain ranges. It is listed as Vulnerable in the IUCN's Red List. The large home range and low population densities of this species mandate range-wide conservation prioritization. Two efforts for range-wide snow leopard conservation planning have been conducted based on expert opinion, but both were constrained by limited knowledge and the difficulty of evaluating complex processes, such as connectivity across large landscapes. Here, we compile > 6000 snow leopard occurrence records from across its range and corresponding environmental covariates to build a model of global snow leopard habitat suitability. Using spatial prioritization tools, we identi!ed seven large continuous habitat patches as global snow leopard Landscape Conservation Units (LCUs). Each LCU faces differing threat levels from poaching, anthropogenic development, and climate change. We identi!ed ten po- tential inter-LCU linkages, and centrality analysis indicated that Tianshan-Pamir-Hindu Kush-Karakorum, Altai, and the linkage between them play a critical role in maintaining the global snow leopard habitat connectivity.
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Solari, K. A., Morgan, S., Poyarkov, A. D., Weckworth, B., Samelius, G., Sharma, K., Ostrowski, S., Ramakrishnan, U., Kubanychbekov, Z., Kachel, S., Johansson, O., Lkhagvajav, P., Hemmingmoore, H., Alexandrov, D. Y., Bayaraa, M., Grachev, A., Korablev, M. P., Hernandez-Blanco, J. A., Munkhtsog, B., Rosenbaum, B., Rozhnov, V. V., Rajabi, A. M., Noori, H., Armstrong, E. E., Petrov, D. A. (2023). Extreme in Every Way: Exceedingly Low Genetic Diversity in Snow Leopards Due to Persistently Small Population Size. bioRxiv, , 1–24.
Abstract: Snow leopards (Panthera uncia) serve as an umbrella species whose conservation benefits their high-elevation Asian habitat. Their numbers are believed to be in decline due to numerous Anthropogenic threats; however, their conservation is hindered by numerous knowledge gaps. They are the least studied genetically of all big cat species and little is known about their historic population size and range, current population trends, or connectivity across their range. Here, we use whole genome sequencing data for 41 snow leopards (37 newly sequenced) to assess population connectivity, historic population size, and current levels of genetic diversity. Among our samples, we find evidence of a primary genetic divide between the northern and southern part of the range around the Dzungarian Basin and a secondary divide south of Kyrgyzstan around the Taklamakan Desert. However, we find evidence of gene flow, suggesting that barriers between these groups are permeable. Perhaps most noteworthy, we find that snow leopards have the lowest genetic diversity of any big cat species, likely due to a persistently small population size throughout their evolutionary history. Without a large population size or ample standing genetic variation to help buffer them from any forthcoming Anthropogenic challenges, snow leopard persistence may be more tenuous than currently appreciated.
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Weckworth, B. (2021). Snow Leopard (Panthera uncia) Genetics: The Knowledge Gaps, Needs, and Implications for Conservation. Journal of the Indian Institute of Science, , 1–12.
Abstract: Conservation geneticists apply genetic theory and techniques to preserve endangered species as dynamic entities, capable of coping with environmental change and thus minimizing their risk of extinction. Snow leopards are an umbrella species of High Asia, and a keystone for maintaining biodiversity within this fragile ecosystem. A clear understanding of patterns of snow leopard genetic diversity is critical for guiding conservation initiatives that will ensure their long-term persistence. Yet, a comprehensive analysis of snow leopard genetic variation is lacking. The number of published snow leopard genetic studies is far fewer than for other imperiled big cats. Here, I review the limited genetic work to date on snow leopards and the significant knowledge gaps to be filled. An emphasis must be placed on describing and understanding population genetic dynamics within and among meta-populations to provide information about the interactions between landscapes and the micro-evolutionary processes of gene flow and genetic drift. These results can be used to evaluate the levels and dynamics of genetic and demographic connectivity. A lack of connectivity, particularly in the low density, small populations that typify snow leopards, can lead to multiple demographic and genetic consequences, including inbreeding depression, loss of adaptive potential, and heightened susceptibility to demographic and environmental stochasticity. New efforts in conservation research on snow leopards should focus on this line of inquiry, and the opportunities and challenges for that are outlined and discussed to encourage the required, and considerable, transboundary partnerships and collaborations needed to be successful.
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Xiao, L., Hua, F., Knops, J. M. H., Zhao, X., Mishra, C., Lovari, S., Alexander, J. S., Weckworth, B., Lu, Z. (2022). Spatial separation of prey from livestock facilitates coexistence of a specialized large carnivore with human land use. Animal Conservation, , 1–10.
Abstract: There is an increasing emphasis in conservation strategies for large carnivores on facilitating their coexistence with humans. Justification for coexistence strategies should be based on a quantitative assessment of currently remaining large carnivores in human-dominated landscapes. An essential part of a carnivore’s coexistence strategy has to rely on its prey. In this research, we studied snow leopards Panthera uncia whose habitat mainly comprises human-dominated, unprotected areas, to understand how a large carnivore and its primary prey, the bharal Pseudois nayaur, could coexist with human land use activities in a large proportion of its range. Using a combination of livestock census, camera trapping and wildlife surveys, across a broad gradient of livestock grazing intensity in a 363 000 km2 landscape on the Tibetan Plateau, we found no evidence of livestock grazing impacts on snow leopard habitat use, bharal density and spatial distribution, even though livestock density was 13 times higher than bharal density. Bharal were found to prefer utilizing more rugged habitats at higher elevations with lower grass forage conditions, whereas livestock dominated in flat valleys at lower elevations with higher productivity, especially during the resource-scarce season. These findings suggest that the spatial niche separation between bharal and livestock, together with snow leopards’ specialized bharal diet, minimized conflicts and allowed snow leopards and bharal to coexist in landscapes dominated by livestock grazing. In recent years, reduced hunting and nomadic herder’s lifestyle changes towards permanent residence may have further reinforced this spatial separation. Our results indicated that, for developing conservation strategies for large carnivores, the niche of their prey in relation to human land-use is a key variable that needs to be evaluated.
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