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Aim: High‐elevation specialist species are threatened by climate change and habitat loss, and their distributions are becoming increasingly reduced and fragmented. In such a context, dispersal ability is crucial to maintain gene flow among patches of suitable habitat. However, information about dispersal is often lacking for these species, especially for those taxa that are usually considered as good dispersers such as birds. We adopted a landscape genomics approach to investigate dispersal in a climate‐sensitive high‐elevation specialist bird. Our aims were to assess the levels of gene flow within a wide mountain area, and to assess the effects of geographic distance and landscape characteristics on dispersal, by testing the isolation by distance (IBD) hypothesis against the isolation by resistance (IBR) hypothesis. Location: European Alps. Taxon: Montifringilla nivalis. Methods: We sampled individuals from several breeding areas and obtained single nucleotide polymorphism (SNP) data by ddRAD sequencing. We then calculated site‐ and individual level genetic distances and individual inbreeding coefficients. To test IBD versus IBR, we related genetic distances to both geographic distances and different measures of landscape resistance by using maximum likelihood population effects models. Results: Gene flow among breeding areas was partly restricted, and we found support for IBD, indicating that geographic distance limits snowfinch dispersal. Spatial patterns of genetic distances suggested that philopatry strongly contributed to determine the observed IBD. High inbreeding coefficients in several individuals indicated frequent mating among relatives. Main Conclusions: Restricted dispersal and frequent inbreeding within 'sky island' systems can also occur in highly mobile species, because their potential ability to cover very large distances can be counteracted by high philopatry levels that are likely related to high dispersal costs. IBD and philopatry will increasingly hinder snowfinch dispersal among suitable areas within the future more restricted and fragmented breeding range, increasing the risks of local extinctions. [ABSTRACT FROM AUTHOR]

Microhabitat utilisation holds a pivotal role in shaping a species' ecological dynamics and stands as a crucial concern for effective conservation strategies. Despite its critical importance, microhabitat use has frequently been addressed as static, centering on microhabitat preference. Yet, a dynamic microhabitat use that allows individuals to adjust to fine-scale spatio-temporal prey fluctuations, becomes imperative for species thriving in challenging environments. High-elevation ecosystems, marked by brief growing seasons and distinct abiotic processes like snowmelt, winds, and solar radiation, feature an ephemeral distribution of key resources. To better understand species' strategies in coping with these rapidly changing environments, we delved into the foraging behaviour of the white-winged snowfinch Montifringilla nivalis, an emblematic high-elevation passerine. Through studying microhabitat preferences during breeding while assessing invertebrate prey availability, we unveiled a highly flexible microhabitat use process. Notably, snowfinches exhibited specific microhabitat preferences, favoring grass and melting snow margins, while also responding to local invertebrate availability. This behaviour was particularly evident in snow-associated microhabitats and less pronounced amid tall grass. Moreover, our investigation underscored snowfinches' fidelity to foraging sites, with over half located within 10 m of previous spots. This consistent use prevailed in snow-associated microhabitats and high-prey-density zones. These findings provide the first evidence of dynamic microhabitat use in high-elevation ecosystems and offer further insights into the crucial role of microhabitats for climate-sensitive species. They call for multi-faceted conservation strategies that go beyond identifying and protecting optimal thermal buffering areas in the face of global warming to also encompass locations hosting high invertebrate densities. [ABSTRACT FROM AUTHOR]

The ecosystem services offered by pollinators are vital for supporting agriculture and ecosystem functioning, with bees standing out as especially valuable contributors among these insects. Threats such as habitat fragmentation, intensive agriculture, and climate change are contributing to the decline of natural bee populations. Remote sensing could be a useful tool to identify sites of high diversity before investing into more expensive field survey. In this study, the ability of Unoccupied Aerial Vehicles (UAV) images to estimate biodiversity at a local scale has been assessed while testing the concept of the Height Variation Hypothesis (HVH). This hypothesis states that the higher the vegetation height heterogeneity (HH) measured by remote sensing information, the higher the vegetation vertical complexity and the associated species diversity. In this study, the concept has been further developed to understand if vegetation HH can also be considered a proxy for bee diversity and abundance. We tested this approach in 30 grasslands in the South of the Netherlands, where an intensive field data campaign (collection of flower and bee diversity and abundance) was carried out in 2021, along with a UAV campaign (collection of true color-RGB-images at high spatial resolution). Canopy Height Models (CHM) of the grasslands were derived using the photogrammetry technique "Structure from Motion" (SfM) with horizontal resolution (spatial) of 10 cm, 25 cm, and 50 cm. The accuracy of the CHM derived from UAV photogrammetry was assessed by comparing them through linear regression against local CHM LiDAR (Light Detection and Ranging) data derived from an Airborne Laser Scanner campaign completed in 2020/2021, yielding an R 2 of 0.71. Subsequently, the HH assessed on the CHMs at the three spatial resolutions, using four different heterogeneity indices (Rao's Q, Coefficient of Variation, Berger–Parker index, and Simpson's D index), was correlated with the ground-based flower and bee diversity and bee abundance data. The Rao's Q index was the most effective heterogeneity index, reaching high correlations with the ground-based data (0.44 for flower diversity, 0.47 for bee diversity, and 0.34 for bee abundance). Interestingly, the correlations were not significantly influenced by the spatial resolution of the CHM derived from UAV photogrammetry. Our results suggest that vegetation height heterogeneity can be used as a proxy for large-scale, standardized, and cost-effective inference of flower diversity and habitat quality for bees. [ABSTRACT FROM AUTHOR]

The morphology of bird wings is subject to a variety of selective pressures, including migration, predation, habitat structure and sexual selection. Variation in wing morphology also occurs at the intraspecific and intrapopulation level, and can be related to sex, age, migration strategy and environmental factors. The relationship between environment and intraspecific variation in wing morphology is still poorly understood. In this work, we studied the relationship between wing morphology and breeding environment in a high‐elevation specialist bird, the water pipit Anthus spinoletta. We calculated wing isometric size, pointedness and convexity of 84 birds mist‐netted at breeding sites in year 2021 in the European Alps. We then searched for associations between these traits and potentially relevant breeding site characteristics (vegetation structure, elevation, latitude). For all wing traits, sex and one or more environmental factors best explained the variation, with environmental factors explaining between 3 and 8% of the variation. Wing size was negatively related to tree cover and wing convexity was negatively related to bush cover. Elevation contributed to explain variation in wing pointedness, but the direction of its effect was unclear. The negative relationship between wing size and tree cover could be due to intraspecific competition, i.e. to the relegation of smaller winged low‐quality individuals in marginal grassland areas. Higher wing convexity could improve predator escape ability in areas with scarce protecting vegetation, with possible effects on habitat choice. These findings represent one of the few demonstrated cases of wing morphology–environment relationships at the intraspecific level. [ABSTRACT FROM AUTHOR]

Understanding the effects of landscape composition and configuration, climate, and topography on bird diversity is necessary to identify distribution drivers, potential impacts of land use changes, and future conservation strategies. We surveyed bird communities in a study area located in the Central Alps (Autonomous Province of South Tyrol, northeast Italy), by means of point counts and investigated taxonomic and functional diversity at two spatial scales along gradients of land use/land cover (LULC) intensity and elevation. We also explored how environmental variables influence bird traits and red-list categories. Models combining drivers of different types were highly supported, pointing towards synergetic effects of different types of environmental variables on bird communities. The model containing only LULC compositional variables was the most supported one among the single-group models: LULC composition plays a crucial role in shaping local biodiversity and hence bird communities, even across broad landscape gradients. Particularly relevant were wetlands, open habitats, agricultural mosaics made up of small habitat patches and settlements, ecotonal and structural elements in agricultural settings, and continuous forests. To conserve bird diversity in the Alps, planning and management practices promoting and maintaining small fields, structural elements, and a mosaic of different LULC types should be supported, while preserving continuous forests at the same time. Additionally, pastures, extensively used meadows, and wetlands are key to conservation. These strategies might mitigate the impacts of global change on bird diversity in the Alps and in other European mountain areas. [ABSTRACT FROM AUTHOR]

• Community composition of other taxa changed consistently with bird communities and indicator species within farmlands. • Efficiency of different bird indices as bioindicators varied across landscapes and taxa. • Species richness, number of threatened and farmland birds were most selected indices. • 14 different indicator species were found for grasslands and crops. • European serin and Alpine accentor were the most selected indicator species. Biodiversity loss is a global issue, particularly in mountain regions, where land-use/land-cover and climate change dramatically impact on species and communities. Sound ecological research and up-to-date information on biodiversity are needed to support conservation efforts. However, this information is often difficult and costly to obtain. Therefore, bioindicators serve as surrogates to provide information on the entire biocenosis. Birds are considered excellent bioindicators as they occupy different ecological niches and trait spaces. We present a study about the efficiency of birds as bioindicators for the diversity of other taxa in a mountain region in the Central Alps. We surveyed bird communities at 115 sites across a gradient of different grasslands and crops and compared them with the diversity of other taxa (bats, butterflies, grasshoppers, arachnids, and vascular plants). We aimed to identify indicator bird species for grasslands and crops, to assess cross-community concordance between birds and other taxa, and to model the efficiency of bird indices and indicator species as bioindicators of the diversity across habitat types and taxa. We identified indicator bird species for different grassland and crop types and found that efficiency of bird indices and single species varied for habitat types and taxa. We highlight the importance of using carefully selected bioindicators in biodiversity monitoring and conservation planning, and the need for an integrated and interdisciplinary approach for biodiversity research. Moreover, by looking at a combination of different indices we can gain a more comprehensive understanding of ecosystem functioning. We also provide a framework for the use of bird-based monitoring programs and bird-derived indices to guide biodiversity conservation, and emphasise the importance of incorporating different bioindicators into biodiversity research and monitoring to provide a more comprehensive understanding of ecological biodiversity patterns and trends. [ABSTRACT FROM AUTHOR]

The Barred Warbler Sylvia nisoria is a critically endangered breeding species in Italy, given the severe decline suffered in the last decades and the reduced population size. South Tyrol, an inner Alpine region, is the northernmost Italian breeding area of this warbler, but we lacked recent information about the distribution and population size. In this study, based on surveys carried out in the year 2019 and other recent observations, we assessed a very restricted current distribution of this warbler, and we estimated a population size of 10-30 pairs. We also observed a singing male at unusually high elevation. A comparison of our results to historical data suggests a strong reduction in distribution compared to the 1980s 1990s. The changes in agricultural practices of the last decades might have contributed to determine such decline. Appropriate conservation measures are urgently needed to try to avoid the local extinction of the species. [ABSTRACT FROM AUTHOR]

Salamandra atra atra is the most widespread subspecies of the Alpine Salamander, both in Italy and in the other parts of the species distribution range. However, in particular for Italian populations, its ecology and demographic parameters are poorly known. We studied biometry (length, mass, body condition index) and demography (population density, sex ratio, proportion of gravid females) of this fully terrestrial salamander in the "Paneveggio- Pale di San Martino" Natural Park in the Dolomites. We used removal methods to estimate abundance on a surface of about 1000 m2. Density estimate of adults was 472 salamanders/ha, which falls within the density estimates that are available for this taxon. Sexes did not differ significantly in size and body mass. Body sizes of adults included the maximum sized salamander recorded in Italy. There was a high rate of gravid females (50%), which were comparable in size with non-gravid females. Males and non-gravid females did not show significant differences in their body condition index. [ABSTRACT FROM AUTHOR]

Capsule: Fine-scale use of climate-sensitive habitats by White-winged Snowfinches Montifringilla nivalis is affected by landscape composition, which thus modulates the potential impact of climate change. Aims: To explore the fine-scale habitat use for foraging by breeding White-winged Snowfinches, with the aim of identifying the potential impacts of climate change on their dependence on habitat characteristics in the wider landscape, which could shape the species' response to climate change. Pairs mostly relying on snow could be at higher risk due to a decrease in spring snow-cover, but the reliance on snow may be mediated by the presence of alternative habitats in the landscape. Methods: The White-winged Snowfinch uses alpine grassland, snowfields and melting snow margins for capturing prey during nestling rearing and is threatened by earlier snowmelt induced by climate change. We investigated habitat use in 17 Snowfinch pairs in relation to landscape composition within a 300 m buffer around their nests. Results: The use of snowfields and snow-bare margins was positively associated with wind intensity (probably due to greater wind-borne arthropod fallout with wind), and negatively associated with grassland cover (i.e. the main alternative habitat) and date within the season. Conclusions: Fine-scale habitat selection was affected by landscape composition: the availability of patches of alternative habitats decreased the reliance on more climate-sensitive resources, modulating the potential impact of climate change. Coupling assessments of fine-scale resource selection with broader habitat descriptors, which are easier to assess over broader scales, may help understand and predict climate change impacts. [ABSTRACT FROM AUTHOR]

Black grouse were once widespread in England, but have declined over the past 150 years due largely to habitat changes. In 1998, 773 males remained and following the instigation of conservation measures population size increased to 1029 in 2006, but population range remained similar. We hypothesized that range expansion was limited by the short dispersal ranges of males (up to 1 km) relative to females (up to 19 km), resulting in yearling females dispersing into areas without males. We tested this hypothesis by moving males to establish new leks and to stimulate range expansion. Three release sites were chosen beyond the southern edge of the male range, but were within the perceived dispersal distance of females, and where habitats were considered suitable and generalist predators were controlled. Between 2006 and 2010, 17 males were released at the first site, and a further 18 and 27 respectively at two sites between 2011 and 2014. Males were caught at night, fitted with radio‐transmitters and hard released. In the first spring following translocation, 98% of males were observed displaying. Males displayed an average 3.6 km (range 0.6 to 27.1 km) from their release point. Leks were established at all sites, with 14 different leks occupied in spring 2015 contributing to the re‐colonisation of seven 10 km grid squares. Mean annual survival in the first year following translocation was 0.77 (0.63–0.86, 95% CL) and was similar to that of birds measured in previous studies in the core northern England range. This suggests that under appropriate circumstances translocation can be a helpful conservation tool in stimulating range expansion. [ABSTRACT FROM AUTHOR]

Changes in agricultural land use and management are largely responsible for the current global biodiversity crisis. Addressing this crisis necessitates a change in management practices that are considered to limit biodiversity. Comparing intensive land-use forms with their extensive and traditional counterparts can help define good practice example for integrated conservation. We compare remnants of traditional meadow orchards with intensively managed apple orchards in a mountain region by investigating the multi-taxonomic diversity of seven groups (including vascular plants, wild bees, diurnal butterflies, orthopterans, spiders, birds, and bats) and macro-invertebrates inhabiting four habitat strata (soil, ground-dwelling, herb, and tree layer). Each group and stratum was sampled with a target sampling method. We found a consistent trend of higher abundance, diversity, and presence of threatened species in meadow orchards compared to apple orchards. Specifically, wild bees, butterflies, orthopterans, and birds showed significantly lower diversity in apple orchards across different diversity indices. Furthermore, multi-taxonomic indices of all taxa and most habitat strata followed the same trend, supporting the conclusion that these findings are applicable to the entire orchard ecosystem. We conclude that traditional agroforestry systems, such as meadow orchards, could represent a well-suited good-practice example for integrated biodiversity conservation in the agricultural landscape. Finally, we emphasize the importance of maintaining traditional management practices through effective conservation measures such as subsidies as part of agri-environmental schemes. • Meadow orchards support higher multi-taxonomic diversity than apple orchards. • Wild bees, butterflies, orthopterans, and birds have lower diversity in apple orchards. • Management impact is concordant over multiple taxa and four habitat strata. • Meadow orchards are proposed as examples of integrated biodiversity conservation. [ABSTRACT FROM AUTHOR]

The majority of predictions about the impacts of climate change on wildlife have relied either on the study of species' physiological tolerance or on broad-scale distribution models. In comparison, little attention has been paid to species' mechanistic responses to fine-grained, climate-induced modifications of habitat suitability. However, such studies would be pivotal to the understanding of species' ecological requirements (and hence their adaptive potential to environmental change) and the design of management strategies. We investigated foraging microhabitat selection in a potentially climate-change sensitive species, the white-winged snowfinch Montifringilla nivalis , during the breeding season in the Alps. Our microhabitat selection model considered topography, ground-cover variables and sward height within a 5-m radius at foraging and control locations. Habitat selection was positively affected by grassland cover, negatively by sward height and quadratically by snow cover (optimum around 40%); birds avoided anthropized (urban areas, roads) sites. We estimated past (1976) and future (2066) climate-driven changes in foraging microhabitat suitability, assuming a progressively earlier date of snowmelt due to increasing temperatures over this entire time span. We then modelled the potential impact of snowmelt (and related sward height) on habitat suitability under two scenarios: maintaining the current situation (i.e. irregular seasonal grazing) and implementing targeted management in an attempt to mitigate impacts of earlier snowmelt. Predicted foraging habitat suitability (estimated as the fraction of suitable plots) significantly declined over time (−23% between 1976 and 2016, further 32% loss by 2066). However, model outputs demonstrated that maintaining sward height below 6 cm on breeding grounds (e.g. by regular grazing) would significantly decrease the predicted loss of suitable foraging habitat. Detailed information about patterns of resource exploitation allows the identification of mechanistic, functional responses of species to environmental change, and enables an evaluation of habitat management options that can buffer against the detrimental effects of global warming. [ABSTRACT FROM AUTHOR]