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Cold‐adapted species at high elevations may be especially impacted by global warming since they may be limited in their capacity to adapt to changing conditions or may be prevented from shifting their distributions upwards if no suitable habitats are available.The latter may be true for Erebia nivalis, a high‐elevation specialist that mainly occurs in the Austrian Alps and on few mountaintops in Switzerland, where its taxonomic and conservation status remains unclear.We aimed to clarify the relationships among geographically isolated populations of E. nivalis using whole‐genome resequencing data to reconstruct population connectivity and phylogenetic relationships. We inferred current and historical effective population sizes and combined these with tests for ecological differentiation based on available occurrence data to re‐evaluate the conservation status of E. nivalis.Our results confirm that Swiss and Austrian E. nivalis should be considered different evolutionarily significant units for conservation purposes, as they are marked by moderate genomic differentiation, distinct demographic histories and a difference in the abiotic conditions of their habitats.In both Austria and Switzerland, we found rapid uphill range shifts over the last decades, little population connectivity, low current effective population sizes and low genetic diversity. The above, combined with the low dispersal capacity of this 2‐year lifecycle species and its need to overwinter under snow, which is rapidly retreating from several regions of the Alps, leads us to suggest that the status of E. nivalis should be updated to 'Vulnerable' or 'Endangered' in the European, Swiss and Austrian Red Lists. [ABSTRACT FROM AUTHOR]

Living in a warming world requires adaptations to altered annual temperature regimes. In Europe, spring is starting earlier, and the vegetation period is ending later in the year. These climatic changes are leading not only to shifts in distribution ranges of flora and fauna, but also to phenological shifts. Using long‐term observation data of butterflies and moths collected during the past decades across northern Austria, we test for phenological shifts over time and changes in the number of generations. On average, Lepidoptera adults emerged earlier in the year and tended to extend their flight periods in autumn. Many species increased the annual number of generations. These changes were more pronounced at lower altitudes than at higher altitudes, leading to an altered phenological zonation. Our findings indicate that climate change does not only affect community composition but also the life history of insects. Increased activity and reproductive periods might alter Lepidoptera–host plant associations and food webs. [ABSTRACT FROM AUTHOR]

Context: Agricultural intensification has led to strong homogenization of landscapes. Field copses have become larger, the boundaries between habitats became sharper, and land plots have been cultivated more intensively. In parallel, most field copses, ruderal areas and hedgerows were removed. As a result, ecotones and rarely used microhabitats largely disappeared. In consequence, many suitable habitats for species such as butterflies vanished and the permeability of the landscape decreased, with negative effects on biodiversity. Objective: In this study we analyse land-use and habitat configuration, and butterfly diversity for the years 1953 and 2018 for northern Austria. Methods: We assessed land cover and landscape configuration for the years 1953 and 2018 on a field-by-field basis across northern Austria, based on aerial and satellite images. We studied butterfly diversity for these two identical periods of time. Results: Our data show a decrease of the number of field copses over the past decades and a reduction in landscape complexity. The expected number of butterflies per sample unit of an assumed species decreased significantly. Particularly sedentary specialists decreased, while the proportion of mobile generalists increased. Conclusions: Our study underlines the general trend of landscape and faunal homogenization, which specifically leads to the vanishing of extensively used micro-habitats and the loss of sedentary specialist species. [ABSTRACT FROM AUTHOR]

Annual insect abundances are determined by short‐term population fluctuations and long‐term trends in community composition. Any assessment of this temporal variability needs long‐term quantitative data on abundances. Here we use museum data (1940–2017) of butterflies and burnet moths from southwestern Germany and central Austria comprising 220,758 records from 155 species, and 55,641 records from 170 species, respectively. We ask whether population fluctuations and long‐term population trends are spatially synchronized across larger spatial distances (>300 km) according to the Moran effect, and whether common trends in community composition and stability exist? Population fluctuations of 85.5% of species jointly occurring in both study regions were positively correlated (mean r = 0.30 ± 0.03). Comparing different time windows, we found different sets of species being in spatial synchrony reflecting temporal changes in butterfly community composition. Mesophilic, habitat generalist, and dispersive species were significantly more synchronized than xerothermophilic, habitat specialist, and sedentary species. Long‐distance travelers were particularly synchronized. In both study regions, species rank orders became less even with time. Stability in community composition increased with time with an ongoing trend to faunal homogenization, but not to species loss. Our study points to global and not to local drivers behind trends in butterfly population fluctuations and compositional stability, in the present case to altered land use and urbanization as major drivers toward synchrony and homogenization. Finally, our data have implications for conservation strategies as they strongly indicate that natural landscape structures are associated with higher faunal compositional variability in comparison to agricultural and urban landscapes. [ABSTRACT FROM AUTHOR]

Context: Biodiversity is severely decreasing at a global scale since several decades. There are significant changes in species community compositions, reductions of species richness and abundances of arthropods, as well as of arthropod biomass. Land use intensification and climate change are assumed to be main drivers causing biodiversity change and loss. However, proximate effects of land use, landscape configuration, topography and climate on species richness and species community composition were only rarely analysed. Objective: We study the effects of current land cover, landscape structures and climate on butterfly and burnet moth species diversity and community composition across northern Austria (i.e. the federal state of Salzburg). Methods: We compiled observation data of butterflies and burnet moths for the past 40 years. We divided faunal data, land cover data and data on climate into 5 × 5 km2 grid cells. We classified all lepidopterans assessed into groups according to their distribution, behaviour, ecology and life-history. Results: We found higher species richness and temporal community shifts in higher elevations, and where topographic heterogeneity is high. Habitat connectivity has a positive impact on ecologically specialised, sedentary, and endangered species. Mean temperature and precipitation positively influenced species richness. Conclusions: Both, land-use and climate strongly shape biodiversity structures. In particular, landscape heterogeneity promotes the diversity of ecological niches, which subsequently accelerates species diversity, including specialist species. Agricultural intensification in higher elevations and at steep slopes is more difficult and therefore less attractive, and thus the level of biodiversity is still high. In addition, climate warming might lead to the accumulation of species in higher elevations. Our study further underlines the relevance of habitat conservation at lower elevations, where not all habitat types are conserved sufficiently. [ABSTRACT FROM AUTHOR]

High mountain ecosystems are extreme habitats for all organisms and therefore demand specific adaptations. In this context, we studied the ecology of the butterfly Euphydryas aurinia debilis in the High Tauern (Austria) and compared the obtained data against the ecology of the species in lower elevation habitats. We performed mark-release-recapture studies over the entire flight periods (end of June to end of July) in 2007 and 2008 to analyse the fundamental ecological parameters of a population. The demography of males and females was similar in both years, and no indication of typical protandry was detected. We observed a generally low dispersal of the individuals in both years, but males dispersed significantly more than females in 2008; this finding of low vagility was supported by allozyme analyses. Furthermore, butterflies survived periods of several days of continuously closed snow cover without any indication of increased mortality rates. In these three traits, this alpine population of E. aurinia apparently has ecological and physiological adaptations to the extreme requirements of high-altitude habitats and strongly deviates from the lower elevation populations.