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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.
Keywords: animal welfare; capture; collar; felid; GPS; immobilization; Panthera uncia; trapping
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Johansson, O., Rauset, G. R., Samelius, G., McCarthy, T., Andren, H., Tumursukh, L., Mishra, C. (2016). Land sharing is essential for snow leopard conservation. Biological Conservation, (203), 1–7.
Abstract: Conserving large carnivores in an increasingly crowded planet raises difficult challenges. A recurring debate is whether large carnivores can be conserved in human used landscapes (land sharing) or whether they require specially designated areas (land sparing). Here we show that 40% of the 170 protected areas in the global range of the snow leopard (Panthera uncia) are smaller than the home range of a single adult male and only 4– 13% are large enough for a 90% probability of containing 15 or more adult females. We used data from 16 snow leopards equipped with GPS collars in the Tost Mountains of South Gobi, Mongolia, to calculate home range size and overlap using three different estimators: minimum convex polygons (MCP), kernel utility distributions (Kernel), and local convex hulls (LoCoH). Local convex hull home ranges were smaller and included lower proportions of unused habitats compared to home ranges based on minimum convex polygons and Kernels. Intra-sexual home range overlapwas low, especially for adult males, suggesting that snowleopards are territorial. Mean home range size based on the LoCoH estimates was 207 km2 ± 63 SD for adult males and 124 km2 ± 41 SD for adult females. Our estimates were 6–44 times larger than earlier estimates based on VHF technology when comparing similar estimators, i.e. MCP. Our study illustrates that protected areas alone will not be able to conserve predatorswith large home ranges and conservationists and managers should not restrict their efforts to land sparing.
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Ulziibadrakh, T., Uudus, B., Lkhagvajav, P., Alexander, J. S., Johansson, O., Sharma, K., Samelius, G. (2023). Variation in plant composition along a gradient of increasing distance from wells in a mountain steppe in southern Mongolia. Snow Leopard Reports, , 10–16.
Abstract: Habitat degradation and heavy grazing by livestock are common conservation challenges across the steppes of Mongolia and Central Asia. Livestock grazing patterns are generally not uniform and are typically greater near campsites and watering holes. In this study, we examined how plant composition in a mountain steppe in southern Mongolia varied along a gradient of increasing distance from wells. We found that the cover and average height of Ephedra prezewalskii increased with increasing distance from the wells whereas soil chemistry and the other variables of plant composition that we examined were similar along the gradient of increasing distance from the wells. These results suggest relatively limited impact of livestock grazing on plant composition in our study. However, our study was limited in space and time and further studies are needed to understand the impact of livestock grazing in this mountain steppe in southern Mongolia.
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Samelius, G., Suryawanshi, K., Frank, J., Agvaantseren, B., Baasandamba, E., Mijiddorj, T., Johansson, O., Tumursukh, L., Mishra, C. (2020). Keeping predators out: testing fences to reduce livestock depredation at night-time corrals. Oryx, , 1–7.
Abstract: Livestock depredation by large carnivores is a global conservation challenge, and mitigation measures to reduce livestock losses are crucial for the coexistence of large carnivores and people. Various measures are employed to reduce livestock depredation but their effectiveness has rarely been tested. In this study, we tested the effectiveness of tall fences to reduce livestock losses to snow leopards Panthera uncia and wolves Canis lupus at night-time corrals at the winter camps of livestock herders in the Tost Mountains in southern Mongolia. Self-reported livestock losses at the fenced corrals were reduced from a mean loss of 3.9 goats and sheep per family and winter prior to the study to zero losses in the two winters of the study. In contrast, self-reported livestock losses in winter pastures, and during the rest of the year, when herders used different camps, remained high, which indicates that livestock losses were reduced because of the fences, not because of temporal variation in predation pressure. Herder attitudes towards snow leopards were positive and remained positive during the study, whereas attitudes towards wolves, which attacked livestock also in summer when herders moved out on the steppes, were negative and worsened during the study. This study showed that tall fences can be very effective at reducing night-time losses at corrals and we conclude that fences can be an important tool for snow leopard conservation and for facilitating the coexistence of snow leopards and people.
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Tallian, A., Mattisson, J., Samelius, G., Odden, J., Mishra, C., Linnell, J. D. C., Lkhagvajav, P., Johansson, O. (2023). Wild versus domestic prey: Variation in the kill-site behavior of two large felids. Global Ecology and Conservation, 47(e026750), 1–13.
Abstract: Livestock depredation is an important source of conflict for many terrestrial large carnivore
species. Understanding the foraging behavior of large carnivores on domestic prey is therefore important for both mitigating conflict and conserving threatened carnivore populations. Handling time is an important, albeit often overlooked, component of predatory behavior, as it directly influences access to food biomass, which can affect predator foraging efficiency and subsequent kill rates. We used long-term data on snow leopards (Panthera uncia) in Mongolia (Asia) and Eurasian lynx (Lynx lynx) in Norway (Europe) to examine how large carnivore foraging patterns varied between domestic and wild prey, and how the different landscape characteristics affected those patterns. Our results suggest handling time was generally shorter for domestic compared to wild prey. For snow leopards, rugged terrain was linked to increased handling time for larger prey. For lynx, handling time increased with terrain ruggedness for domestic, but not wild, prey, and was greater in closed compared to open habitats. There were also other differences in snow leopard and lynx foraging behavior, e.g., snow leopards also stayed longer at, and remained closer to, their kill sites than lynx. Shorter handling time suggests that felids may have utilized domestic prey less effectively than wild prey, i.e., they spent less time consuming their prey. This could a) result in an energetic or fitness cost related to decreased felid foraging efficiency caused by the risk of anthropogenic disturbance, or b) exacerbate conflict if reduced handling time associated with easy prey results in increased livestock depredation. |
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Johansson, O., McCarthy, T., Samelius, G., Andren, H., Tumursukh, L., Mishra, C. (2015). Snow leopard predation in a livestock dominated landscape in Mongolia. Biological Conservation, 184, 251–258.
Abstract: Livestock predation is an important cause of endangerment of the snow leopard (Panthera uncia) across
its range. Yet, detailed information on individual and spatio-temporal variation in predation patterns of snow leopards and their kill rates of livestock and wild ungulates are lacking. We collared 19 snow leopards in the Tost Mountains, Mongolia, and searched clusters of GPS positions to identify prey remains and estimate kill rate and prey choice. Snow leopards killed, on average, one ungulate every 8 days, which included more wild prey (73%) than livestock (27%), despite livestock abundance being at least one order of magnitude higher. Predation on herded livestock occurred mainly on stragglers and in rugged areas where animals are out of sight of herders. The two wild ungulates, ibex (Capra ibex) and argali (Ovis ammon), were killed in proportion to their relative abundance. Predation patterns changed with spatial (wild ungulates) and seasonal (livestock) changes in prey abundance. Adult male snow leopards killed larger prey and 2–6 times more livestock compared to females and young males. Kill rates were considerably higher than previous scat-based estimates, and kill rates of females were higher than kill rates of males. We suggest that (i) snow leopards prey largely on wild ungulates and kill livestock opportunistically, (ii) retaliatory killing by livestock herders is likely to cause greater mortality of adult male snow leopards compared to females and young males, and (iii) total off-take of prey by a snow leopard population is likely to be much higher than previous estimates suggest. |
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Sharma, K., Bayrakcismith, R., Tumursukh, L., Johansson, O., Sevger, P., McCarthy, T., Mishra, C. (2014). Vigorous Dynamics Underlie a Stable Population of the Endangered Snow Leopard Panthera uncia in Tost Mountains, South Gobi, Mongolia. Plos One, 9(7).
Abstract: Population monitoring programmes and estimation of vital rates are key to understanding the mechanisms of population growth, decline or stability, and are important for effective conservation action. We report, for the first time, the population trends and vital rates of the endangered snow leopard based on camera trapping over four years in the Tost Mountains, South Gobi, Mongolia. We used robust design multi-season mark-recapture analysis to estimate the trends in abundance, sex ratio, survival probability and the probability of temporary emigration and immigration for adult and young snow leopards. The snow leopard population remained constant over most of the study period, with no apparent growth (l = 1.08+20.25). Comparison of model results with the ‘‘known population’’ of radio-collared snow leopards suggested
high accuracy in our estimates. Although seemingly stable, vigorous underlying dynamics were evident in this population, with the adult sex ratio shifting from being male-biased to female-biased (1.67 to 0.38 males per female) during the study. Adult survival probability was 0.82 (SE+20.08) and that of young was 0.83 (SE+20.15) and 0.77 (SE +20.2) respectively, before and after the age of 2 years. Young snow leopards showed a high probability of temporary emigration and immigration (0.6, SE +20.19 and 0.68, SE +20.32 before and after the age of 2 years) though not the adults (0.02 SE+20.07). While the current female-bias in the population and the number of cubs born each year seemingly render the study population safe, the vigorous dynamics suggests that the situation can change quickly. The reduction in the proportion of male snow leopards may be indicative of continuing anthropogenic pressures. Our work reiterates the importance of monitoring both the abundance and population dynamics of species for effective conservation. |
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Johansson, O., Samelius, G., Wikberg, E, Chapron, G., Mishra, C., Low, M. (2020). Identification errors in camera- trap studies result in systematic population overestimation. Scientific Reports, 10(6393), 1–10.
Abstract: Reliable assessments of animal abundance are key for successful conservation of endangered species. For elusive animals with individually-unique markings, camera-trap surveys are a benchmark standard for estimating local and global population abundance. Central to the reliability of resulting abundance estimates is the assumption that individuals are accurately identified from photographic captures. To quantify the risk of individual misidentification and its impact on population abundance estimates we performed an experiment under controlled conditions in which 16 captive snow leopards (Panthera uncia) were camera-trapped on 40 occasions and eight observers independently identified individuals and recaptures. Observers misclassified 12.5% of all capture occasions, resulting in systematically inflated population abundance estimates on average by one third (mean ± SD = 35 ± 21%). Our results show that identifying individually-unique individuals from camera-trap photos may not be as reliable as previously believed, implying that elusive and endangered species could be less abundant than current estimates indicate.
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Johansson, O., Ausilio, G., Low, M., Lkhagvajav, P., Weckworth,
B., Sharma, K. (2020). The timing of breeding and independence for snow leopard females
and their cubs. Mammalian Biology, .
Abstract: Significant knowledge gaps persist on snow leopard demography
and reproductive behavior. From a GPS-collared population in Mongolia, we estimated the timing of mating, parturition and independence. Based on three mother–cub pairs, we describe the separation phase of the cub from its mother as it gains independence. Snow leopards mated from January–March and gave birth from April–June. Cubs remained with their mother until their second winter (20–22 months of age) when cubs started showing movements away from their mother for days at a time. This initiation of independence appeared to coincide with their mother mating with the territorial male. Two female cubs remained in their mothers’ territory for several months after initial separation, whereas the male cub quickly dispersed. By comparing the relationship between body size and age of independence across 11 solitary, medium-to-large felid species, it was clear that snow leopards have a delayed timing of separation compared to other species. We suggest this may be related to their mating behavior and the difficulty of the habitat and prey capture for juvenile snow leopards. Our results, while limited, provide empirical estimates for understanding snow leopard ecology and for parameterizing population models. |
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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. |