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Islam, M., Sahana, M., Areendran, G., Jamir, C., Raj, K., Sajjad, H. (2023). Prediction of potential habitat suitability of snow leopard (Panthera uncia) and blue sheep (Pseudois nayaur) and niche overlap in the parts of western Himalayan region. Geo: Geography and Environment, 10(e00121), 1–15.
Abstract: The snow leopard (Panthera uncia) and blue sheep (Pseudois nayaur) are the inhabitants of remote areas at higher altitudes with extreme geographic and climatic conditions. The habitats of these least-studied species are crucial for sustaining the Himalayan ecosystem. We employed the Maximum Entropy (MaxEnt) species distribution model to predict the potential habitat suitability of snow leopards and blue sheep and extracted common overlapped niches. For this, we utilised presence location, bio-climatic and environmental variables, and correlation analysis was applied to reduce the negative impact of multicollinearity. A total of 134 presence locations of snow leopards and 64 for blue sheep were selected from the Global Biodiversity Information Facility (GBIF). The annual mean temperature (Bio1) was found to be the most useful and highly influential factor to predict the potential habitat suitability of snow leopards. Annual mean temperature, annual precipitation and isothermality were the major influencing factors for blue sheep habitat suitability. Highly influential bio-climatic, topographic and environmental variables were integrated to construct the model for predicting habitat suitability. The area under the curve (AUC) values for snow leopard (0.87) and blue sheep (0.82) showed that the models are under good representation. Of the total area investigated, 47% was suitable for the blue sheep and 38% for the snow leopards. Spatial habitat assessment revealed that nearly 11% area from the predicted suitable habitat class of both species was spatially matched (overlapped), 48.6% area was unsuitable under niche overlap and 40.5% area was spatially mismatched niche. The presence of snow leopards and blue sheep in some highly suitable areas was not observed, yet such areas have the potential to sustain these elusive species. The other geographical regions interested in exploring habitat suitability may find the methodological framework adopted in this study useful for formulating an effective conservation policy and management strategy.
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Johansson, O., Agvaantseren, B., Jackson, R., Kachel, S., Kubanychbekov, Z., McCarthy, T., Mishra, C., Ostrowski, S., Kulenbekov, R., Rajabi, A. M., Subba, S. (2022). Body measurements of free-ranging snow leopards across their range. Snow Leopard Reports, 1, 1–6.
Abstract: We provide body measurements of snow leopards collected from 55 individuals sampled in five of the major mountain ranges within the species distribution range; the Altai, Hindu Kush, Himalayas, Pamirs and Tien Shan mountains. Snow leopards appear to be similarly sized across their distribution range with mean body masses of 36 kg and 42 kg for adult females and adult males, respectively. In contrast to other large felids, we found little variation in body size and body mass between the sexes; adult males were on average 5% longer and 15% heavier than adult females.
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Johansson, O., Alexander, J. S., Lkhagvajav, P., Mishra, C., Samelius, G. (2024). Natal dispersal and exploratory forays through atypical habitat in the mountain-bound snow leopard. Ecology, 2024(e4264), 1–4.
Abstract: Understanding how landscapes affect animal movements is key to effective conservation and management (Rudnick et al., 2012; Zeller et al., 2012). Movement defines animal home ranges, where animals generally access resources such as food and mates, and also their dispersal and exploratory forays. These movements are important for individual survival and fitness through genetic exchange within and between populations and for colonization of unoccupied habitats (Baguette et al., 2013; MacArthur & Wilson, 1967). Dispersal and exploratory movements typically occur when young animals leave their natal range and establish more permanent home ranges (Greenwood, 1980; Howard, 1960). In mammals, natal dispersal of males is usually more frequent and happens over greater distances compared with that of females (Clobert et al., 2001; Greenwood, 1980).
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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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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., Mishra, C., Chapron, G., Samelius, G., Lkhagvajav, P., McCarthy, T., Low, M. (2022). Seasonal variation in daily activity patterns of snow leopards and their prey. Nature Portfolio, 12(21681), 1–11.
Abstract: The daily and seasonal activity patterns of snow leopards (Panthera uncia) are poorly understood, limiting our ecological understanding and hampering our ability to mitigate threats such as climate change and retaliatory killing in response to livestock predation. We fitted GPS-collars with activity loggers to snow leopards, Siberian ibex (Capra sibirica: their main prey), and domestic goats (Capra hircus: common livestock prey) in Mongolia between 2009 and 2020. Snow leopards were facultatively nocturnal with season-specific crepuscular activity peaks: seasonal activity shifted towards night- sunrise during summer, and day-sunset in winter. Snow leopard activity was in contrast to their prey, which were consistently diurnal. We interpret these results in relation to: (1) darkness as concealment for snow leopards when stalking in an open landscape (nocturnal activity), (2) low-intermediate light preferred for predatory ambush in steep rocky terrain (dawn and dusk activity), and (3) seasonal activity adjustments to facilitate thermoregulation in an extreme environment. These patterns suggest that to minimise human-wildlife conflict, livestock should be corralled at night and dawn in summer, and dusk in winter. It is likely that climate change will intensify seasonal effects on the snow leopard’s daily temporal niche for thermoregulation in the future.
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Johansson, O., Nyam, E., Lkhagvajav, P., Alexander, J. A., Samelius, G. (2023). Predation Patterns and Hunting Behaviour of Snow Leopards: Insights from an Ibex Hunt. Snow Leopard Reports, , 6–9.
Abstract: The hunting behaviours of the snow leopard (Panthera uncia) are poorly understood. In this note, we describe the successful hunt of an adult male ibex (Capra sibirica) by a known male snow leopard in Tost Mountains, Mongolia. The hunt started in a mountain slope close to three large boulders and progressed downhill for 115 m until it concluded at the bottom of a drainage. By comparing the habitat where the ibex was killed to the kill sites of 158 ibex and 17 argali (Ovis ammon) that were killed by GPS-collared snow leopards, we demonstrate that the majority (62%) of these kills occurred in drainages. We propose that in successful hunts, snow leopards commonly ambush from above, causing prey individuals to typically flee downhill. Thereby the prey maintain their momentum and it is not until they are slowed down upon reaching the bottom of the drainage that the snow leopards are able to subdue them.
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Johansson, O., Ullman, K., Lkhagvajav, P., Wiseman, M.,
Malmsten, J., Leijon, M. (2020). Detection and Genetic Characterization of Viruses Present in
Free-Ranging Snow Leopards Using Next-Generation Sequencing. Frontiers in Veterinary Science, 7(645), 1–9.
Abstract: Snow leopards inhabit the cold, arid environments of the high
mountains of South and Central Asia. These living conditions likely affect the abundance and composition of microbes with the capacity to infect these animals. It is important to investigate the microbes that snow leopards are exposed to detect infectious disease threats and define a baseline for future changes that may impact the health of this endangered felid. In this work, next-generation sequencing is used to investigate the fecal (and in a few cases serum) virome of seven snow leopards from the Tost Mountains of Mongolia. The viral species to which the greatest number of sequences reads showed high similarity was rotavirus. Excluding one animal with overall very few sequence reads, four of six animals (67%) displayed evidence of rotavirus infection. A serum sample of a male and a rectal swab of a female snow leopard produced sequence reads identical or closely similar to felid herpesvirus 1, providing the first evidence that this virus infects snow leopards. In addition, the rectal swab from the same female also displayed sequence reads most similar to feline papillomavirus 2, which is the first evidence for this virus infecting snow leopards. The rectal swabs from all animals also showed evidence for the presence of small circular DNA viruses, predominantly Circular Rep-Encoding Single-Stranded (CRESS) DNA viruses and in one case feline anellovirus. Several of the viruses implicated in the present study could affect the health of snow leopards. In animals which are under environmental stress, for example, young dispersing individuals and lactating females, health issues may be exacerbated by latent virus infections. |
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Kachel, S. M., Karimov, K., Wirsing, A. J. (2022). Predator niche overlap and partitioning and potential interactions in the mountains of Central Asia. Journal of Mammalogy, XX(X), 1–11.
Abstract: Direct and indirect interactions among predators affect predator fitness, distribution, and overall community structure. Yet, outside of experimental settings, such interactions are difficult to observe and thus poorly understood. Patterns of niche overlap among predators reflect and shape community interactions and may therefore help elucidate the nature and intensity of intraguild interactions. To better understand the coexistence of two apex predators, snow leopards (Panthera uncia) and wolves (Canis lupus), we investigated their spatial, temporal, and dietary niche overlap in summer in the Pamir Mountains of Tajikistan. We estimated population- level space use via spatial capture–recapture models based on noninvasive genetics and camera traps, diel activity patterns based on camera trap detections, and diet composition from prey remains in carnivore scats, from which we estimated coefficients between 0 and 1 for overlap in space, time, and diet, respectively. Snow leopards and wolves displayed moderate spatial partitioning (0.26, 95% confidence interval [CI]: 0.17–37), but overlapping temporal (0.77, 95% CI: 0.64–0.90) and dietary (0.97, 95% CI: 0.80–0.99) niches. Both predators relied on seasonally abundant marmots (Marmota caudata) rather than wild ungulates, their typical primary prey, suggesting that despite patterns of overlap that were superficially conducive to exploitation competition and predator facilitation, prey were likely not a limiting factor. Therefore, prey-mediated interactions, if present, were unlikely to be a major structuring force in the ecosystem. By implication, carnivore conservation planning and monitoring in the mountains of Central Asia should more fully account for the seasonal importance of marmots in the ecosystem.
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Kachel, S., Anderson, K., Shokirov, Q. (2022). Predicting carnivore habitat use and livestock depredation risk with false-positive multi-state occupancy models. Biological Conservation, 271(109588), 1–10.
Abstract: The cycle of livestock depredation and retaliatory killing constitutes a major threat to large carnivores worldwide and imposes considerable hardships on human communities. Mitigation efforts are often undertaken with little knowledge of ecological underpinnings and patterns of depredation, limiting conservationists' ability to develop, prioritize, and evaluate solutions. Carnivore detection and depredation data from interviews in affected communities may help address this gap, but such data are often prone to false-positive uncertainty. To address these challenges in the Pamir Mountains of Tajikistan we collected snow leopard, lynx, wolf, and bear detection and depredation reports from local communities via semi-structured interviews. We used a novel hierarchical multi-species multi-state occupancy model that accounted for potential false-positives to investigate carnivore site use and depredation concurrently with respondents' apparent vulnerability to that risk. Estimated false-positive probabilities were small, but failure to account for them overstated site use probabilities and depredation risk for all species. Although individual vulnerability was low, depredation was nonetheless commonplace. Carnivore site use was driven by clear habitat associations, but we did not identify any clearly important large-scale spatial correlates of depredation risk despite considerable spatial variation in that risk. Respondents who sheltered livestock in household corrals reinforced with wire mesh were less likely to report snow leopard depredations. Reducing depredation and retaliation at adequately large scales in the Pamirs will likely require a portfolio of species-specific strategies, including widespread proactive corral improvements. Our approach expanded inference on the often-cryptic processes surrounding human-carnivore conflict even though structured wildlife data were scarce.
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