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The ‘landscape of fear’ concept offers valuable insights into wildlife behaviour, yet its practical integration into habitat management for conservation remains underexplored. In this study, conducted in the subtropical monsoon grasslands of Bardia National Park, Nepal, we aimed to bridge this gap through a multi-year, landscape-scale experimental investigation in Bardia National Park, Nepal. The park has the highest density of tigers (with an estimated density of ~7 individuals per 100 km2) in Nepal, allowing us to understand the effect of habitat management on predation risk and resource availability especially for three cervid species: chital (Axis axis), swamp deer (Rucervus duvaucelii) and hog deer (Axis porcinus). We used plots with varying mowing frequency (0–4 times per year), size (ranging from small: 49 m2 to large: 3600 m2) and artificial fertilisation type (none, phosphorus, nitrogen) to assess the trade-offs between probable predation risk and resources for these cervid species, which constitute primary prey for tigers in Nepal. Our results showed distinct responses of these deer to perceived predation risk within grassland habitats. Notably, these deer exhibited heightened use of larger plots, indicative of a perceived sense of safety, as evidenced by the higher occurrence of pellet groups in the larger plots (mean = 0.1 pellet groups m−2 in 3600 m2 plots vs. 0.07 in 400 m2 and 0.05 in 49 m2 plots). Furthermore, the level of use by the deer was significantly higher in larger plots that received mowing and fertilisation treatments compared to smaller plots subjected to similar treatments. Of particular interest is the observation that chital and swamp deer exhibited greater utilisation of the centre (core) areas within the larger plots (mean = 0.21 pellet groups m−2 at the centre vs. 0.13 at the edge) despite the edge (periphery) also provided attractive resources to these deer. In contrast, hog deer did not display any discernible reaction to the exper

Natural pest and weed regulation are essential for agricultural production, but the spatial distribution of natural enemies within crop fields and its drivers are mostly unknown. Using 28 datasets comprising 1204 study sites across eight Western and Central European countries, we performed a quantitative synthesis of carabid richness, activity densities and functional traits in relation to field edges (i.e. distance functions). We show that distance functions of carabids strongly depend on carabid functional traits, crop type and, to a lesser extent, adjacent non-crop habitats. Richness of both carnivores and granivores, and activity densities of small and granivorous species decreased towards field interiors, whereas the densities of large species increased. We found strong distance decays in maize and vegetables whereas richness and densities remained more stable in cereals, oilseed crops and legumes. We conclude that carabid assemblages in agricultural landscapes are driven by the complex interplay of crop types, adjacent non-crop habitats and further landscape parameters with great potential for targeted agroecological management. In particular, our synthesis indicates that a higher edge–interior ratio can counter the distance decay of carabid richness per field and thus likely benefits natural pest and weed regulation, hence contributing to agricultural sustainability.

Understanding where species occur using species distribution models has become fundamental to ecology. Although much attention has been paid to invasive species, questions about climate change related range shifts of widespread insect pests remain unanswered. Here, we incorporated bioclimatic factors and host plant availability into CLIMEX models to predict distributions under future climate scenarios of major cereal pests of the Sitobion grain aphid complex (Sitobion avenae, S. miscanthi, and S. akebiae). Additionally, we incorporated the application of irrigation in our models to explore the relevance of a frequently used management practice that may interact with effects of climate change of the pest distributions. RESULTS: Our models predicted that the area potentially at high risk of outbreaks of the Sitobion grain aphid complex would increase from 41.3% to 53.3% of the global land mass. This expansion was underlined by regional shifts in both directions: expansion of risk areas in North America, Europe, most of Asia, and Oceania, and contraction of risk areas in South America, Africa, and Australia. In addition, we found that host plant availability limited the potential distribution of pests, while the application of irrigation expanded it. CONCLUSION: Our study provides insights into potential risk areas of insect pests and how climate, host plant availability, and irrigation affect the occurrence of the Sitobion grain aphid complex. Our results thereby support agricultural policy makers, farmers, and other stakeholders in their development and application of management practices aimed at maximizing crop yields and minimizing economic losses.

The umbrella species concept is a frequently used concept in conservation since the conservation of an umbrella species may benefit other species. Keystone species are often suggested as potential umbrella species, but the validity of this approach remains uncertain. Moreover, climate change can have a multidirectional effect on the distribution of species, in which the distribution of umbrella species can be affected differently than that of beneficiary species. The validity of applying the umbrella species concept in conservation may thus be jeopardised by climate change. This study assessed the potential of two keystone species, the plateau pika (Ochotona curzoniae) and the Daurian pika (Ochotona dauurica), to be umbrella species for 13 potentially beneficiary species under current and future environmental conditions. Of these 13 species, five currently only co-occur with the plateau pika, five only with the Daurian pika, and three with both pika species. Current and future distributions of the pika species and potentially beneficiary species were predicted using bioclimatic and land-use variables. Range overlaps, Pearson correlations, niche similarity tests and relative suitability tests were performed to assess the umbrella potential of both pika species. Our results show that at present, both pika species may be considered to be umbrella species, benefitting several co-occurring species. However, species that currently co-occur with both pika species will not benefit from conservation of either of the pikas in the future years under climate change scenarios. The plateau pika loses its potential to act as umbrella species for two of the four species which currently may benefit. We can conclude that keystone species like pikas can act as umbrella species for carefully selected potentially beneficiary species under current conditions. Due to climate change related shifts in species distributions, they may however lose their umbrella species status in the future

Indiscriminate fire is rampant throughout subtropical South and Southeast Asian grasslands. However, very little is known about the role of fire and pyric herbivory on the functioning of highly productive subtropical monsoon grasslands lying within Cwa-climatic region. We collected grass samples from 60 m x 60 m plots and determined vegetation physical and chemical properties at regular 30-day intervals from April to July 2020, starting from 30 days after fire to assess post-fire regrowth forage quality. We counted pellet groups for the same four months from 2 m x 2 m quadrats that were permanently marked with pegs along the diagonal of each 60 m x 60 m plot to estimate grazing intensity to the progression of post-fire regrowth. We observed strong and significant reductions in crude protein (mean value 9.1 to 4.1 [55% decrease]) and phosphorus (mean value 0.2 to 0.11 [45% decrease]) in forage collected during different time intervals i.e., from 30 days to 120 days after fire. Mesofaunal deer utilised the burned areas extensively for a short period, i.e., up to two months after fire when the burned areas contained short grasses with a higher level of crude protein and phosphorus. Grazing intensity of chital (Axis axis) to post-fire regrowth differed significantly over time since fire, with higher intensity of use at 30 days after fire. Grazing intensity of swamp deer (Rucervus duvaucelii) did not differ significantly until 90 days after fire, however, decreased significantly after 90 days since fire. Large-scale indiscriminate single event fires thus may not fulfil nutritional requirements of all species in mesofaunal deer community in these subtropical monsoon grasslands. We recommend for a spatio-temporal manipulation of fire to reinforce grazing feedback and to yield for the longest possible period a reasonably good food supply for the conservation of mesofaunal deer.

Endemic vertebrates are a crucial component of biodiversity, yet face disproportionally high extinction risk as climate and land-use changes drive habitat loss. Large protected areas are therefore deemed necessary to mitigate biodiversity loss. In 2021, China’s Giant Panda National Park (GPNP, 27,134 km2) was established in one of the global endemism hotspots. In this study we ask the question whether this large national park is able to conserve the many threatened endemic vertebrates occurring in the region in the face of climate and land-use changes, in order to assess the long-term effectiveness of the GPNP. We used species distribution modeling techniques to project the distributions of 40 threatened terrestrial (and freshwater) endemic vertebrates under land-use and climate change scenarios SSP2–4.5, SSP3–7.0 and SSP5–8.5 in 2081–2100, and assessed the extent to which their distributions are covered by the GPNP, now and in the future. We found that by 2081–2100, two thirds of the threatened endemic vertebrates are predicted to lose part (15–79%, N = 4) of or (nearly) their entire (80–100% loss, N = 23) range under all three climate and land-use change scenarios. Consequently, fewer species are predicted to occur in the GPNP than at present. Our findings confirm the high vulnerability of threatened endemic species to climate and land-use changes, despite protected areas. Habitat loss due to climate and land-use changes elevate extinction risk of species in endemism hotspots across the globe. Urgent, widespread and intensified mitigation measures and adaptation measures are required at a landscape scale for effective conservation efforts in the future.

We randomly laid down 1 m × 1 m quadrats with equally spaced grids of 10 cm × 10 cm in both the grazing lawns and tall grasslands. We laid down a total of 160 quadrats (eight in each sampling site) and recorded bare ground, litter, animal droppings and vegetation. Within each quadrat, we used the point intercept method at 100 sampling points to assess the percentage cover of the different plant species. We only used vegetation hits for calculating the Shannon-Wiener diversity index and species richness. We used grid corners as the point to record the hits. We measured grass height at three random points within each 1 m × 1 m quadrat with a ruler to 0.5 cm precision. We chose three different points in different direction within a quadrat to measure the grass height. We assessed grazing intensity by visually estimating the bite marks within a quadrat at a scale from 0 to 3 [i.e., 0 – not grazed, 1 – lightly grazed, up to 25% of quadrat area grazed; 2 – moderately grazed, (up to 50% grazed), and 3 – heavily grazed ( more than 50% grazed)]. We clipped the vegetation at ground level in a 20 × 20 cm frame in the centre of each quadrat and determined fresh weight using a digital weighing scale [with a capacity of 600 g and accuracy of 0.5 mg; Brand: Equal (class II)] immediately after clipping. We hand-sorted the samples into green leaf, green stem, dry leaf and dry stem which were subsequently dried in the shade at ambient temperature (~30 °C) for five days until air-dry before recording the air-dry weight. Air-dried samples of green leaf and green stem were stored in paper bags for separate chemical analyses. We collected soil subsamples from each quadrat. The soil samples (n = 20) were placed in airtight zip-lock plastic bags for chemical analyses. The dataset (file name: GrazingLawns_TallGrasslands_BardiaNP_Nepal.xlsx) contains three sheets: Sheet 1(veg_count_data) contains record of the grass species observed from 10 cm x 10 cm frame within a 1 m x 1m quadrat. Zero in

Ongoing climate change is expected to have impacts on crops, insect pests, and plant pathogens and poses considerable threats to sustainable food security. Existing reviews have summarized impacts of a changing climate on agriculture, but the majority of these are presented from an ecological point of view, and scant information is available on specific species in agricultural applications. This paper provides an overview of impacts of climate change on two staple crops, wheat and rice. First, the direct effects of climate change on crop growth, yield formation, and geographic distribution of wheat and rice are reviewed. Then, the effects of climate change on pests and pathogens related with wheat and rice, and their interactions with the crops are summarized. Finally, potential management strategies to mitigate the direct impacts of climate change on crops, and the indirect impacts on crops through pests and pathogens are outlined. The present overview aims to aid agriculture practitioners and researchers who are interested in wheat and rice to better understand climate change related impacts on the target species.

Fire is rampant throughout subtropical South and Southeast Asian grasslands. However, very little is known about the role of fire and pyric herbivory on the functioning of highly productive subtropical monsoon grasslands lying within the Cwa climatic region. We assessed the temporal effect of fire on postfire regrowth quality and associated pyric-herbivory in the subtropical monsoon grasslands of Bardia National Park, Nepal. Every year, grasslands are burned as a management intervention in the park, especially between March and May. Within a week after fire, at the end of March 2020, we established 60 m × 60 m plots within patches of burned grassland in the core area of the Park. We collected grass samples from the plots and determined physical and chemical properties of the vegetation at regular 30-day intervals from April to July 2020, starting from 30 days after fire to assess postfire regrowth forage quality. We counted pellet groups of cervids that are abundant in the area for the same four months from 2 m × 2 m quadrats that were permanently marked with pegs along the diagonal of each 60 m × 60 m plot to estimate intensity of use by deer to the progression of postfire regrowth. We observed strong and significant reductions in crude protein (mean value 9.1 to 4.1 [55% decrease]) and phosphorus (mean value 0.2 to 0.11 [45% decrease]) in forage collected during different time intervals, that is, from 30 days to 120 days after fire. Deer utilized the burned areas extensively for a short period, that is, up to two months after fire when the burned areas contained short grasses with a higher level of crude protein and phosphorus. The level of use of postfire regrowth by chital (Axis axis) differed significantly over time since fire, with higher intensity of use at 30 days after fire. The level of use of postfire regrowth by swamp deer (Rucervus duvaucelii) did not differ significantly until 90 days after fire, however, decreased significantly after 90 days since fir

The speed with which restoration will, or can, be accomplished depends on the initial state and location of the sites. However, many factors can undermine the process of choosing sites that are deemed the best ecological choice for restoration. Little attention has been paid to whether site selection follows ecological criteria and how this may affect restoration success. We used habitat inventory data to investigate whether ecological criteria for site selection and restoration have been followed, focusing on restoration for the white-backed woodpecker (Dendrocopos leucotos B.) in Sweden. In our study region, which is situated in an intensively managed forest landscape with dense and young stands dominated by two coniferous species, purely ecological criteria would entail that sites that are targeted for restoration would (1) initially be composed of older and more deciduous trees than the surrounding landscape, and (2) be at a scale relevant for the species. Furthermore, restoration should lead to sites becoming less dense and less dominated by coniferous trees after restoration, which we investigated as an assessment of restoration progress. To contextualize the results, we interviewed people involved in the restoration efforts on site. We show that although the first criterion for ecological site selection was largely met, the second was not. More research is needed to assess the motivations of actors taking part in restoration efforts, as well as how they interlink with public efforts. This would allow us to identify possible synergies that can benefit restoration efforts.

Despite well-formulated goals for environmental protection in the forestry sector, the biodiversity crisis remains. Protected habitats are often small, isolated and lack continuity. We studied forest planning at a landscape scale as a method to increase habitat connectivity, and improve conservation values whilst maintaining high levels of forest production. We assessed the financial impacts of landscape planning for the landowners, and present a fee-fund system to solve unequal burdens among them. As case studies, we used three landscapes along a latitudinal gradient in Sweden. The results demonstrate some variation between the landscapes in terms of the total cost for set asides and large differences in terms of the financial impact per landowner. Our conclusion is that forest landscape planning may be a way forward to improve conservation efforts, but given the variation in financial impacts, we propose to combine landscape planning with economic tools for compensation.

Subtropical grasslands interspersed in forests often present mosaics of tall grasslands and grazing lawns with a high variation in structure, biomass and nutrient concentration. However, the impact of such variation on forage quality is still poorly known. We quantified physical and chemical properties of grasses of grazing lawns and tall grasslands, interspersed in the forested region of Bardia National Park, Nepal during the hot-dry season. This area falls within Cwa-climate (Köppen-Geigen climate classification). We found that grasses in grazing lawns had an average bulk density of ~5400 g.m-3 whereas tall grasslands had an average bulk density of ~1000 g.m-3 only. Forage in grazing lawns was comprised of a higher percentage of green leaf (up to 60%) compared to tall grassland (up to 40%). Phosphorus levels in green leaves were below maintenance requirements of wild herbivores (especially for grazers and mixed feeders) on both grazing lawns and tall grasslands. However, average crude protein levels in green leaves from both the grazing lawns and tall grasslands could meet the herbivores maintenance requirement (~7%). Only green leaves on grazing lawns had crude protein levels sufficient enough (9.7%) to meet the requirements of herbivores for maintenance and gestation, though not for lactation. We conclude that, during the hot-dry season, grazing lawns provide forage with a higher quantity and quality than tall grasslands. Consequently, grazing lawns can make a significant contribution to the maintenance or even growth of the grassland dependent wild ungulate population, such as chital (Axis axis), a primary prey species of the endangered tiger (Panthera tigris) in Bardia National Park. The insight of this study will provide a basis for restoring grazing lawns for quality forage, and aid in the conservation and management of wild grazers and mixed feeders.

Climate change is expected to have an impact on the geographical distribution ranges of species. Endemic species and those with a restricted geographic range may be especially vulnerable. The Persian jird (Meriones persicus) is an endemic rodent inhabiting the mountainous areas of the Irano-Turanian region, where future desertification may form a threat to the species. In this study, the species distribution modelling algorithm MaxEnt was used to assess the impact of future climate change on the geographic distribution range of the Persian jird. Predictions were made under two Representative Concentration Pathways and five different climate models for the years 2050 and 2070. It was found that both bioclimatic variables and land use variables were important in determining potential suitability of the region for the species to occur. In most cases, the future predictions showed an expansion of the geographic range of the Persian jird which indicates that the species is not under immediate threat. There are however uncertainties with regards to its current range. Predictions may therefore be an over or underestimation of the total suitable area. Further research is thus needed to confirm the current geographic range of the Persian jird to be able to improve assessments of the impact of future climate change.

GPS collars are frequently used to study the (behavioural) ecology of species. However, such collars can cause behavioural changes and can have negative physiological effects on the individuals wearing them. A pilot study to obtain data on behavioural and physiological effects of GPS collars on the target species would therefore be recommended, especially when it concerns rare or endangered species. The red panda (Ailurus fulgens) is a small carnivore endemic to the mountains of Central Asia that is currently classified as endangered. There is a lack in knowledge on the species ecology which could be enhanced by a study using GPS-technology. As a pilot study, the two adult red pandas in Rotterdam Zoo were observed before and after fitting a GPS-collar, to determine possible behavioural effects of wearing a collar. Although the study did not take place under ideal circumstances, indications of both behavioural, e.g. increased shaking behaviour, and physical, e.g. abrasions, effects of the collar were found. Even though our results were only based on two individuals, our findings stress the need for pilot studies in controlled environments before GPS collars to ensure safety of the study species and validity of the collected data.

Many long-distance migratory bird species are in decline, of which environmental changes, such as climate change and land-use changes, are thought to be important drivers. The effects of environmental change on the migration of these birds have often been studied during spring migration. Fewer studies have explored the impacts of environmental change on autumn migration, especially at stopover sites. However, stopover sites are important, as the quality of these sites is expected to change over time. We investigated impacts of local environmental conditions on the migration strategy and body condition of the Pied Flycatcher (Ficedula hypoleuca) at an autumn migration stopover site using long-term ringing data (1996–2018) and local environmental conditions. We found that although the arrival and departure dates of birds at the stopover site remained unchanged, the body condition (fat score) of the individuals caught decreased, and the stopover duration increased. This suggests that conditions at the stopover site during the autumn migration period have deteriorated over time. This study emphasizes the importance of suitable stopover sites for migratory birds and stresses that changes in environmental conditions during the autumn migration period may be contributing to the current decline in long-distance migratory passerines.

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