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Simple Summary: Mesopredators (i.e., carnivores of small or intermediate body size) are key species for ecosystem stability, especially when larger carnivore populations have declined, as they have important ecosystem functions, such as population size control. They are essential for ecosystem energy circulation. Studies of predators' dietary habits and dietary differentiation between species provide critical information for identifying the structure and dynamics of trophic interactions in an ecosystem. Past research studies focused only on the diet of large carnivores while few detailed dietary datasets of mesopredators exist that present knowledge gaps regarding their coexistence. Using DNA metabarcoding, we studied the prey of three sympatric Mustelidae species in the Northeast Tiger and Leopard National Park. We find that prey preferences were largely partitioned by the three Mustelidae species and that they likely competed over certain dietary items (e.g., frogs and rodents). Our results provide an initial characterization of prey relationships between different Mustelidae species and may be used to inform management on dietary preferences of mesopredators that are affected by anthropogenic activities. Although human disturbance has declined with the creation of the national park, extra management for the protection of ecosystem functions and food webs is still needed. Diet analysis is essential to fully understand the biology of a species and its function within the ecosystem, as well as being key in identifying food web interactions and the population dynamics of predators and prey. The understanding of the diet of small to mid-sized carnivores remains generally lacking or uninformative due to the inability for taxonomic resolution based on morphology. The yellow-throated marten (Martes flavigula), Eurasian river otter (Lutra lutra), and Siberian weasel (Mustela sibirica) are three important Mustelidae species in ecosystems of northeast China. Based on fecal DNA and a next-generation sequencing (NGS) approach, we analyzed the vertebrate prey of these three sympatric Mustelidae. Prey included 7 mammalian taxa, 10 fishes, 2 birds, and 2 amphibians, with 85% of the taxa assigned to the species level. In total, twenty-one vertebrate prey taxa were identified from seven yellow-throated martens, eight Eurasian river otters, and two Siberian weasels. Concerning identified dietary species, 10 taxa were consumed by yellow-throated martens, 14 by Eurasian river otters, and 4 by Siberian weasels. Some prey species were identified in more than one species. Amphibians and fishes were the most dominant Eurasian river otter prey categories, whereas Eurasian badger (Meles leucurus), birds, and rodents were the main yellow-throated marten prey; amphibians and rodents were largely contained in Siberian weasel prey. Among prey items, Dybowski's frog (Rana dybowskii) and Korean field mouse (Apodemus peninsulae) were identified in all three Mustelidae species but our analyses suggest potential diet preferences among Mustelidae species. Future studies should focus on understanding the trophic relationships of these three Mustelidae species, providing valuable information for their conservation planning. [ABSTRACT FROM AUTHOR]

Context: Livestock grazing is one of the most widespread types of anthropogenic land use, even occurs in many protected areas and has become a threat to wildlife worldwide. Understanding livestock-wildlife interactions is crucial for rare large carnivores conservation. In China, free-ranging cattle within forests degrade the habitat of the tigers (Panthera tigris) and leopards (Panthera pardus), but quantitative assessments of how livestock affect the spatial and temporal use by the major ungulate prey of the two endangered felids are very limited. Objectives: This study aimed to examine the interactions of several sympatric wildlife species with livestock at a fine spatiotemporal scale in a human-dominated forest landscape. Methods: Based on a large-scale camera-trapping data across the China-Russia border, we used N-mixture models, two-species occupancy models and activity pattern overlap to understand the effects of cattle grazing on three ungulate species (sika deer Cervus nippon, wild boars Sus scrofa and roe deer Capreolus pygargus). Results: Spatially, with cattle activity increasing, wild boar and roe deer had different degrees of decline in the intensity of habitat use. Sika deer were displaced as more cattle encroached on forest habitat. Temporally, in the presence of cattle, wild boar and sika deer decreased their activities in the day. In addition, three wild ungulates trend to exhibit lower spatiotemporal overlap with cattle at shared camera sites. Conclusions: Our study shows that wildlife species may reduce the probability of habitat use by spatial avoidance and changing the daily activity patterns. We underscore that fine-scale (i.e. camera-site level) spatiotemporal avoidance is likely a key component of co-occurrence between livestock and the sympatry of competing ungulates inhabiting forest ecosystems. Given prey were depressed, efforts to minimize the livestock disturbance on these species need to be considered to ensure their sustained recoveries. [ABSTRACT FROM AUTHOR]

Large carnivores have extensive spatial requirements, with ranges that often span geopolitical borders. Consequently, management of transboundary populations is subject to several political jurisdictions, often with heterogeneity in conservation challenges. In continental Asia there are four threatened leopard subspecies with transboundary populations spanning 23 countries: the Persian Panthera pardus saxicolor, Indochinese P. pardus delacouri, Arabian P. pardus nimr and Amur P. pardus orientalis leopards. We reviewed the status of these subspecies and examined the challenges to, and opportunities for, their conservation. The Amur and Indochinese leopards have the majority (58–100%) of their remaining range in borderlands, and the Persian and Arabian leopards have 23–26% of their remaining ranges in borderlands. Overall, in 18 of 23 countries the majority of the remaining leopard range is in borderlands, and thus in most countries conservation of these subspecies is dependent on transboundary collaboration. However, we found only two transboundary initiatives for Asian leopards. Overall, we highlighted three key transboundary landscapes in regions that are of high importance for the survival of these subspecies. Recent listing of the leopard in the Bonn Convention on the Conservation of Migratory Species of Wild Animals is important, but more international collaboration is needed to conserve these subspecies. We provide a spatial framework with which range countries and international agencies could establish transboundary cooperation for conserving threatened leopards in Asia. [ABSTRACT FROM AUTHOR]

The endangered Amur tiger Panthera tigris altaica is confined primarily to a narrow area along the border with Russia in northeast China. Little is known about the foraging strategies of this small subpopulation in Hunchun Nature Reserve on the Chinese side of the border; at this location, the prey base and land use patterns are distinctly different from those in the larger population of the Sikhote-Alin Mountains of Russia. Using dietary analysis of scats and camera-trapping data from Hunchun Nature Reserve, we assessed spatiotemporal overlap of tigers and their prey and identified prey selection patterns to enhance understanding of the ecological requirements of tigers in northeast China. Results indicated that wild prey constituted 94.9% of the total biomass consumed by tigers; domestic livestock represented 5.1% of the diet. Two species, wild boar Sus scrofa and sika deer Cervus nippon, collectively represented 83% of the biomass consumed by tigers. Despite lower spatial overlap of tigers and wild boar compared to tigers and sika deer, tigers preferentially preyed on boar, likely facilitated by high temporal overlap in activity patterns. Tigers exhibit significant spatial overlap with sika deer, likely favoring a high level of tiger predation on this large-sized ungulate. However, tigers did not preferred roe deer Capreolus pygargus and showed a low spatial overlap with roe deer. Overall, our results suggest that tiger prey selection is determined by prey body size and also overlap in tiger and prey use of time or space. Also, we suggest that strategies designed to minimize livestock forays into forested lands may be important for decreasing the livestock depredation by tigers. This study offers a framework to simultaneously integrate food habit analysis with the distribution of predators and prey through time and space to provide a comprehensive understanding of foraging strategies of large carnivores. [ABSTRACT FROM AUTHOR]

Context: Understanding how large carnivore guilds survive in human-dominated landscapes is key to inform strategies for their conservation in the face of global carnivore declines. Amur tigers and leopards are recovering across the China-Russia border. However, knowledge is limited about competitive interactions between two large cats in Northeast Asia.Objectives: To assess the spatial, temporal and combined spatiotemporal behavioral mechanisms potentially allow co-occurrence between tigers and leopards in a human-dominated forest landscape.Methods: Based on a large-scale camera-trapping data set in Northeast China, we used three different approaches for quantifying spatiotemporal associations: one spatial method (two-species occupancy model), one strictly temporal method (activity pattern overlap), and one spatiotemporal method based on multi-response permutation procedures at shared camera trap sites.Results: Spatially, leopards showed no avoidance of the areas highly used by dominant tigers, but their diurnal activity pattern was significantly different from that of tigers. Spatiotemporal overlap analysis showed fine-scale behavioral avoidance when both co-occurred at camera locations, which further facilitates sympatry. Tigers spatially overlapped with humans, but they were less active during the day when human activities were more frequent. In areas with high cattle density, low occurrence of tigers and leopards may reflect the absence of sika deer, an important prey item for both species.Conclusions: This study provides the first empirical evidence that tigers do not limit leopard distributions, at least in our study area in Northeast Asia. Our results highlighted temporal segregation, not large-scaled spatial avoidance, as a key mechanism promoting coexistence of two large carnivores. Understanding these fine- spatial scale (i.e., camera locations) interactions between sympatric carnivores can help devise management strategies for predator guilds in human-dominated landscapes, currently a major global challenge. [ABSTRACT FROM AUTHOR]

Large carnivore populations are globally threatened by human impacts. Better protection could benefit carnivores, co‐occurring species, and the ecosystems they inhabit. The relationship between carnivores and humans, however, is not always consistent in areas of high human activities and is often mediated through the effects of humans on their ungulate prey. To test assumptions regarding how prey abundance and humans affect carnivore occurrence, density, and daily activity patterns, we assessed tiger–prey–human spatiotemporal patterns based on camera‐trapping data in Hunchun Nature Reserve, a promising core area for tiger restoration in China. Our study area contained seasonally varying levels of human disturbance in summer and winter. We used N‐mixture models to predict the relative abundance of ungulate prey considering human and environmental covariates. We estimated tiger spatial distribution using occupancy models and models of prey relative abundance from N‐mixture models. Finally, we estimated temporal activity patterns of tigers and prey using kernel density estimates to test for temporal avoidance between tigers, prey, and humans. Our results show that human‐related activities depressed the relative abundance of prey at different scales and in different ways, but across species, the relative abundance of prey directly increased tiger occupancy. Tiger occupancy was strongly positively associated with the relative abundance of sika deer in summer and winter. The crepuscular and nocturnal tigers also apparently synchronized their activity with that of wild boar and roe deer. However, tigers temporally avoided human activity without direct spatial avoidance. Our study supports the effects of humans on tigers through human impacts on prey populations. Conservation efforts may not only target human disturbance on predators, but also on prey to alleviate human–carnivore conflict. We use data from the recovering Amur tiger population in China from an extensive remote camera‐trapping study to understand the effects of humans on tigers and their prey in both space and time. Our study showed human affected tigers both by direct temporal avoidance and indirectly via the negative influence of humans on the relative abundance of the primary wild prey of tigers. [ABSTRACT FROM AUTHOR]