Effects of human disturbance on vegetation, prey and Amur tigers in Hunchun Nature Reserve, China

Establishing a protected area network in Xinlong with other effective area-based conservation measures

Protected areas (PAs) are pivotal to biodiversity conservation, yet their efficacy is compromised by insufficient funding and management. So-called other effective area-based conservation measures (OECMs) present a paradigm shift and address PA limitations. Such measures can expand conservation areas, enhance connectivity, and improve the existing system. To assess the conservation status of biodiversity in Tibetan cultural areas in China, we investigated the spatial distribution of wildlife vulnerable to human disturbance (large- and medium-sized mammals and terrestrial birds) in Xinlong, a traditional Tibetan cultural area. In particular, we compared a PA (Xionglongxi Nature Reserve) and OECMs targeting species conservation. We also investigated the relationship of wildlife with human temporal and spatial activities. The OECMs complemented areas not covered by PA, especially in rich understory biodiversity regions. More species in OECMs tolerated human presence than species in the PA. Existing biodiversity reserves failed to cover areas of high conservation value in Tibet and offered limited protection capacity. Expanding PAs and identifying OECMs improved Xinlong's system by covering most biodiversity hotspots. Building on the tradition of wildlife conservation in Tibet, harnessing OECMs may be an effective means of augmenting biodiversity conservation capacity. We recommend further evaluation of OECMs effectiveness and coverage in Tibetan area as a way to enhance the current PA system.

The Minimal Impact of Anthropogenic Disturbances on the Spatial Activities of Leopard Cats in Xinlong, China

The habitat plays a crucial role in ensuring the survival of wildlife. However, the increasing disturbances caused by human activities present a substantial threat to habitats, especially for species such as the leopard cat (Prionailurus bengalensis), which is a significant small predator. Currently, research on leopard cats predominantly focuses on low-altitude regions within its distribution range, leaving plateau areas understudied. To enhance our understanding of the impact of human disturbances on leopard cat habitats, we undertook a study employing infrared camera trappings to monitor leopard cats' activity in Xinlong of southwestern China between 2015 and 2023. We analyzed the spatial distribution and habitat suitability of the leopard cats by utilizing ensemble species distribution models (ESDMs). Moreover, we employed two-species occupancy models to investigate the spatial interaction between leopard cats and human disturbances. The results indicated that (1) the potential suitable habitat area for leopard cats encompassed approximately 1324.93 km2 (14.3%), primarily located along the banks of Yalong river. (2) The distribution of suitable habitat was predominantly influenced by competitors, specifically the yellow-throated marten (YTM), accounting for 52.4% of the influence, as well as environmental factors such as distance to water (DTW) at 12.0% and terrain roughness index (TRI) at 10.0%. Human interference, including cattle presence (4.6%), distance to road (DTD, 4.9%), and distance to settlement (DTS, 3.5%), had a limited impact on the habitat distribution. (3) Within a 5 km radius, habitat suitability increased with proximity to human settlements. (4) Leopard cats exhibited spatial independence from humans and domestic cattle (species interaction factor (SIF) = 1.00) while avoiding domestic horses (SIF = 0.76 ± 0.03). The relatively minor impact of human disturbances in Xinlong could be attributed to traditional cultural practices safeguarding wildlife and the leopard cat's environmental adaptability. We recommend establishing a novel conservation paradigm based on the living dynamics of wildlife communities in Xinlong, thereby offering a more targeted approach to biodiversity preservation in the future.

Assessing mammal population densities in response to urbanization using camera trap distance sampling

Environmental filtering is deemed to play a predominant role in regulating the abundance and distribution of animals during the urbanization process. However, the current knowledge about the effects of urbanization on the population densities of terrestrial mammals is limited. In this study, we compared two invasive mammals (dogs Canis lupus familiaris and cats Felis silvestris) and three indigenous mammals (Siberian weasels Mustela sibirica, Amur hedgehogs Erinaceus amurensis, and Tolai hares Lepus tolai) in response to urbanization using camera trap distance sampling (CTDS) in the rural-urban landscape of Tianjin, China. We used generalized additive mixed models (GAMMs) to test the specific responses of their densities to levels of urbanization. Invasive dogs (2.63 individuals/km2, 95% CI: 0.91-7.62) exhibited similar density estimations to cats (2.15 individuals/km2, 95% CI: 1.31-3.50). Amur hedgehogs were the most abundant species (6.73 individuals/km2, 95% CI: 3.15-14.38), followed by Tolai hares (2.22 individuals/km2, 95% CI: 0.87-5.68) and Siberian weasels (2.15 individuals/km2, 95% CI: 1.06-4.36). The densities of cats, Siberian weasels, and Amur hedgehogs increased with the level of urbanization. The population densities of dogs and cats were only influenced by urban-related variables, while the densities of Siberian weasels and Amur hedgehogs were influenced by both urban-related variables and nature-related variables. Our findings highlight that the CTDS is a suitable and promising method for wildlife surveys in rural-urban landscapes, and urban wildlife management needs to consider the integrated repercussions of urban- and nature-related factors, especially the critical impacts of green space habitats at finer scales.

Impacts of top predators and humans on the mammal communities of recovering temperate forest regions

Top predators are important drivers in shaping ecological community structure via top-down effects. However, the ecological consequences and mechanisms of top predator loss under accelerated human impacts have rarely been quantitatively assessed due to the limited availability of long-term community data. With increases in top predator populations in northern China over the past two decades, forests with varying densities of top predators and humans provide an opportunity to study their ecological effects on mammal communities. We hypothesized a priori of conceptual models and tested these using structural equation models (SEMs) with multi-year camera trap data, aiming to reveal the underlying independent ecological effects of top predators (tigers, bears, and leopards) and humans on mammal communities. We used random forest models and correlations among species pairs to validate results. We found that top predator reduction could be related to augmented populations of large ungulates ("large ungulate release") and mesopredators ("mesopredator release"), consistent with observations of mammal communities in other ecosystems. Additionally, top predator reduction could be related to reduced small mammal abundance. Hierarchical SEMs identified three bottom-up pathways from forest quality to human activities, large ungulates, and some small mammals, and five top-down pathways from human activities and top predators to some small mammals, large ungulates, and mesopredators. Furthermore, our results suggest that humans showed predominant top-down effects on multiple functional groups, partially replacing the role of top predators, rather than be mediated by them; effects of humans and top predators appeared largely independent. Effects of humans on top predators were non-significant. This study provides novel insights into the effects of top predators and humans as super-predators on mammal communities in forest ecosystems and presents cues of bottom-up effects that can be translated into actionable management plans for improving forest quality, thereby supporting top predator recovery and work/life activities of local people.

Quantitative assessment of the risk of human activities on landscape fragmentation: A case study of Northeast China Tiger and Leopard National Park

Risk assessment of human activities on landscape fragmentation in nature reserves can effectively balance the conflict between wildlife conservation and human development. However, previous studies had been unable to quantitatively assess the risk of human activities on landscape fragmentation. Thus, we constructed a risk assessment methodology to quantitatively assess the risk of different human activities on the Landscape Fragmentation Composite Index (LFCI) in the Northeast China Tiger and Leopard National Park (NCTLNP). First, we fitted the relationship curve between LFCI and different human activity factors based on the Generalized Additive Model (GAM) to determine the impact patterns of each factor on LFCI. Secondly, we identified impact risk areas of each human activity factor on LFCI by the location of threshold points in the curve and analyzed their spatiotemporal variation characteristics from 2015 to 2020. The results show that the relationship between LFCI and Land Use Intensity (LUI) showed an inverted "U" shape, the relationship with Population Density (POPD) showed a "rising-flat-rising" trend, and the relationship with Traffic Accessibility (TA) and Industrial and Mining Activity (IMA) showed a positive correlation after a flat interval. In addition, we found that the LUI and IMA impact risk areas were widely distributed and remained stable for five years. But the POPD impact risk area was mainly distributed around settlements and expanded by 6.6 % from 2015 to 2020. The TA impact risk area was distributed in strips and expanded by 16.38 % from 2015 to 2017 due to the construction of the G331 national road. And the joint impact risk area of these four factors expanded by 1.55 times in five years. Our research can provide a reference for ecological risk assessment under the impact of human activities on other nature reserves in the world.

Challenges and Opportunities in Aligning Conservation with Development in China's National Parks: A Narrative Literature Review

As part of its effort to balance economic development with environmental objectives, China has established a new national park system, with the first five locations formally established in 2021. However, as the new parks all host or are proximate to human populations, aligning the socioeconomic needs and aspirations of local communities with conservation aims is critical for the long-term success of the parks. In this narrative review, the authors identify the ecological priorities and socioeconomic stakeholders of each of the five national parks; explore the tensions and synergies between these priorities and stakeholders; and synthesize the policy recommendations most frequently cited in the literature. A total of 119 studies were reviewed. Aligning traditional livelihoods with conservation, limiting road construction, promoting education and environmental awareness, and supporting the development of a sustainable tourism industry are identified as important steps to balance conservation with economic development in the new national parks.

Inferring Land Conditions in the Tumen River Basin by Trend Analysis Based on Satellite Imagery and Geoinformation

The aim of this study was to map the land condition within the area of the Tumen River Basin (TRB), located on the Sino–North Korean border, using trend analysis of environmental factors. The normalized difference vegetation index (NDVI) and land surface temperature (LST) trends over the past 30 years were analyzed to identify areas that have undergone degradation, restoration, and/or a transition. Landsat NDVI and LST were obtained using the Google Earth Engine (GEE) platform. Erosion was also gauged over the same period using the Revised Universal Soil Loss Equation (RUSLE). Our results showed that only 0.3% of the land within the TRB underwent change that can be characterized as statistically significant within the study period. We therefore infer that land degradation may not be a major concern in the study area. Areas with a significant upward trend of soil loss accounted for 0.8% of the basin’s footprint and were mainly distributed upstream of North Korea. However, more than 80% of the area was found to be suffering from water stress, 10% of these areas were statistically significant and most were located downstream.

Understanding Residents’ Perceptions of the Ecosystem to Improve Park–People Relationships in Wuyishan National Park, China

A healthy park–people relationship depends essentially on the fair and sustainable maintenance of rural livelihood. When a protected area is designated, rural people may face restrictions on access to land and resource use. In Wuyishan of China, we analyzed the role of traditional tea cultivation during consistent protected area management to find ways to maintain the stability of this social-ecological system in the new national park era. Based on the social-ecological system meaning perception, we used an intensive social survey to investigate residents’ perception of the ecosystem in terms of tea cultivation and its interaction with conservation policies. Results showed that tea cultivation brought major household income and was associated with multiple cultural services. Protected area management affected land use, and conservation outcomes were more obvious to farmers than economic and social ones. We argue that the multi-functionality of the forest-tea system has the potential to benefit both the local people and the public through conservation-compatible activities at three levels: to regulate biophysical elements in the land plot, to link production and market at the mountain level, and to secure tenure and encourage community participation at the landscape level. This knowledge co-production approach revealed that to avoid a negative park–people relationship, traditional knowledge and people’s right to benefit must be respected.

Cattle Grazing Effects on Vegetation and Wild Ungulates in the Forest Ecosystem of a National Park in Northeastern China

There is evidence that cattle grazing in forests limits big cat abundance. There is concern, too, about competition with wild ungulate prey through bottom-up effects on vegetation. Hence, there have been calls to remove or control forest livestock grazing in aid of restoring endangered large carnivores and their prey. To help inform scientific debate and decision making, we explored cattle-vegetation-prey dynamics in Northeast Tiger and Leopard National Park, northeast China and present a reappraisal of livestock grazing in the context of coexistence and an integrated approach to land use in China. Inside long-term forest grazing enclosures, wild boar (Sus scrofa) density increased with cattle density. Roe deer (Capreolus pygargus) density and occurrence probability of wild boar and roe deer were not influenced by cattle density. Wild ungulate densities were not related with the number of annual shoots, i.e., forage plant abundance. The presence/absence and abundance of annual shoots was not related with cattle density. Wild ungulate density had mixed associations with vegetation structure; arbor tree diameter at breast height (DBH) and habitat “openness” increased with cattle density. Finally, inside and outside enclosures had different vegetation characteristics and wild boar densities, while roe deer densities were equal. We conclude that cattle density and associated changes to vegetation have positive, negative, and neutral effects on two wild ungulate prey species. Each of these factors warrant consideration in evidence-based management decisions in regard to regulating ungulate community composition to support different large predators as preferred prey in core areas and corridors of habitats.

Dispersal of Amur tiger from spatial distribution and genetics within the eastern Changbai mountain of China

Population dispersal and migration often indicate an expanded habitat and reduced inbreeding probability, and to some extend reflects improvement in the condition of the population. The Amur tiger population in the northern region of the Changbai mountain in China mostly distributes along the Sino-Russian border, next to the population in southwest Primorye in Russia. The successful dispersal westward and transboundary movement are crucial for the persistence of the Amur tiger in this area. This study explored the spatial dispersal of the population, transboundary migration, and the genetic condition of the Amur tiger population within the northern Changbai mountain in China, using occurrence data and fecal samples. Our results from 2003 to 2016 showed that the Amur tiger population in this area was spreading westward at a speed of 12.83 ± 4.41 km every three years. Genetic diversity of the Amur tiger populations in southwest Primorye was slightly different than the population in our study area, and the potential individual migration rate between these two populations was shown to be about 13.04%. Furthermore, the relationships between genetic distances and spatial distances indicated the existence of serious limitations to the dispersal of the Amur tiger in China. This study provided important information about spatial dispersal, transboundary migration, and the genetic diversity of Amur tigers in China, showed the urgent need for Amur tiger habitat restoration, and suggested some important conservation measures, such as corridor construction to eliminate dispersal barriers and joint international conservation to promote trans-boundary movement.

Relationships between humans and ungulate prey shape Amur tiger occurrence in a core protected area along the Sino-Russian border

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.