Identifying ecologically matching areas is both challenging and critical for understanding spatial patterns of biodiversity and advancing conservation planning. However, existing approaches often lack spatial flexibility, overlook shape and size constraints, or rely on limited environmental parameters, reducing their effectiveness in real-world applications. To address these limitations, we developed and tested a four-step framework for identifying ecologically and spatially matching areas. Our framework method involved defining the parameters for the comparative analyses; assessing similar environmental conditions between target protected areas and potential matching areas, through a modified version of the multivariate environmental similarity surface (mMESS); simulating randomly distributed polygons that mirror both the shape and surface area of the target protected area; and integrating the simulated polygons with the resulting mMESS to identify areas where environmental similarity, shape, and surface match. Finally, we applied decision criteria to identify real-world matching areas. We tested our approach in both the Northern and the Central Apennines (Italy), comparing a national park in each of these two regions to similar but unprotected areas-specifically excluding national parks, regional parks, and Natura 2000 Network sites. Our framework offers a robust tool for identifying matching and mismatching areas and enhancing our understanding of these areas' spatial distributions and environmental conditions to support conservation planning and management. The framework may be applied to a broad range of ecological studies at various scales and has the potential to guide future conservation efforts and policies.

In the last decades, interest in monitoring and quantifying biodiversity in human-modified landscapes ha increased, as anthropogenic disturbance is recognized as a major driver of biodiversity loss. However, green spaces within disturbed environments can sometimes serve as critical refuges for wildlife. In this study, we collected and analyzed data on bird and butterfly communities across a gradient of anthropogenic disturbance in Bologna (Italy) encompassing urban, agricultural and semi-natural contexts. We found the highest species richness and diversity for both taxa in peri-urban areas with natural and semi-natural habitats, while the dense built-up areas supported fewer, mostly generalist species. Intermediate zones, including parks and gardens, acted as ecological filters, hosting both specialist and generalist species, while agricultural areas favoured birds likely due to their greater vagility, but not butterflies, whose communities showed sharper compositional shifts. Finally, we found that both continuous urban cover, discontinuous high-density urban areas, distance to streets, and wood coverage were the main drivers of α and β diversity in our target groups. Our findings highlighted the importance of habitat heterogeneity and continuity with the natural areas surrounding the city in sustaining biodiversity under anthropogenic disturbance. The integrated analysis of two bioindicator groups along a disturbance gradient produced original and transferable results, offering a replicable model for ecological studies and urban planning in similar contexts.

The bush cricket Saga pedo, listed as Vulnerable globally by the IUCN and included in Annex IV of the EU Habitats Directive, is a parthenogenetic species highly sensitive to environmental changes, facing threats from forest expansion and agricultural intensification. S. pedo prefers dry, open habitats with sparse vegetation, and its pronounced thermo-heliophily makes it an indicator of xerothermic habitats. In many areas of Italy, including the Northern Apennines (Piedmont), semi-natural grasslands are fragmented. Open habitats have been reduced to small, isolated patches surrounded by forests due to the abandonment of agropastoral activities. Consequently, the occurrence of open habitat species is related to the quality and availability of suitable areas and ecological connectivity. We developed a spatial Bayesian framework to identify areas of occurrence for S. pedo. Using the inverse probability of occurrence, we derived ecological corridors among suitable patches. Our findings indicate that the occurrence and connectivity of S. pedo are reduced by intensive cultivation but favored by open habitats with 10-50% woody tree cover, suggesting sustainable land management is crucial for supporting the species. Given the extinction risk S. pedo faces, we urge local administrations to maintain and improve suitable areas and guarantee the network of ecological corridors identified.

Conserving diversity below the species level is vital to maintaining species' adaptive potential. However, defining intra-specific units for conservation is complex due to the often-continuous nature of differentiation, and thus multiple lines of evidence are needed to adequately capture adaptive differences. Caribou (Rangifer tarandus caribou) exemplify this challenge, exhibiting diverse behavioural, genetic, and morphological variation throughout their range, with several populations facing extirpation. We used a long-term telemetry dataset of 302 caribou across the species' range in western Canada to assess individual variation in movement behaviours. This included behaviours hypothesized to be of adaptive significance, such as migration, home range size and shape, and inferred predator avoidance tactics. Gaussian finite mixture models were then used to identify intra-specific behavioural clusters which may be evolutionarily significant, followed by Random Forest models to discern behaviours driving differentiation between clusters. We identified six distinct clusters based on individual variation in behaviour. Differentiation between clusters was significantly influenced by selection for canopy cover (%) at calving events, home range size and shape, migratory behaviour, and geographic location. Since behavioural variation arises from genetic, environmental, and social factors, our results highlight the value of incorporating trait variation into the assessment of evolutionarily significant units for conservation. We advocate for the consideration of behavioural variation, as it offers valuable insights into adaptive differences. This approach holds promise for informing conservation efforts, not only for caribou, but other terrestrial species at risk given the importance of maintaining genetic and phenotypic diversity.

AbstractThe expansion of forest cover and intensification of agriculture represent the main threats to the bush cricket Saga pedo, currently listed as Vulnerable globally by the IUCN and included in Annex IV of the European Union Habitats Directive. Gathering information on its ecology and population size is challenging due to its low abundance and localized distribution. Additionally, the elusive and cryptic behavior of this species reduces the likelihood of its detection, potentially resulting in population underestimations. Thus, in this study, we aimed to (1) estimate S. pedo population size in relation to environmental variables and prey availability and (2) predict abundance of S. pedo in our study area for future monitoring in nearby territories. We found that the population of S. pedo in our study area consists of 197 (±115) individuals with a detection probability of 21.01% (±11.09). Detection probability of S. pedo further decreases on windy days. Moreover, we found that the investigated population of S. pedo occupies suboptimal areas, as highlighted not only by the predicted abundances but also by the association between S. pedo and other subfamilies of orthoptera that are ecologically very distant from our target species and mostly linked to mesophilic biotopes. Most of the individuals we observed are concentrated in small clearings completely within wooded matrices and therefore isolated from each other. Based on our results, it is possible that forest expansion toward open meadows represents the main threat to this population, transforming the clearings and xeric meadows (to which S. pedo is linked) into small and fragmented patches that are suboptimal and insufficient to host viable populations.

ABSTRACTBackgroundMonitoring biodiversity is crucial in biogeography. Citizen science and biodiversity platforms have revolutionized data access across taxa, but they struggle to provide robust raw data essential for conservation decisions.AimsThis study addresses data gaps for under‐represented species and locations, observer expertise variability, and the lack of absence data and sampling effort information to improve data representation and suitability for statistical analyses.Materials & MethodsWe collected, compared to IUCN‐recognized taxonomic groups, all worldwide living being (animal, plant and fungi) observations held by four major biodiversity platforms: eBird, GBIF, iNaturalist, and Observation.org. We also organized such observations by country of origin and based on their Human Development Index (HDI).ResultsWe found that, while GBIF, iNaturalist, and Observation.org cover all life forms, birds are the most observed (eBird is a bird‐specific platform), whereas fish, other marine organisms, arthropods, and invertebrates are dramatically underrepresented. Moreover, none of the above‐mentioned biodiversity platforms considered or directly analysed expertise variability among observers and, apart from eBird, the other three biodiversity platforms do not accommodate data on species absence and sampling effort.Discussion and ConclusionFinally, we found that species observations on biodiversity platforms considered in this study are skewed towards high HDI countries, primarily North America and Europe. By enhancing the effectiveness of biodiversity platforms, this study has the potential to significantly advance the field of biogeography, paving the way for more informed and effective conservation strategies. Overall, our findings underscore the untapped potential of these platforms in contributing to our understanding of the spatial and temporal patterns of biodiversity.

Climate change has been associated with both latitudinal and elevational shifts in species’ ranges. The extent, however, to which climate change has driven recent range shifts alongside other putative drivers remains uncertain. Here, we use the changing distributions of 378 European breeding bird species over 30 years to explore the putative drivers of recent range dynamics, considering the effects of climate, land cover, other environmental variables, and species’ traits on the probability of local colonisation and extinction. On average, species shifted their ranges by 2.4 km/year. These shifts, however, were significantly different from expectations due to changing climate and land cover. We found that local colonisation and extinction events were influenced primarily by initial climate conditions and by species’ range traits. By contrast, changes in climate suitability over the period were less important. This highlights the limitations of using only climate and land cover when projecting future changes in species’ ranges and emphasises the need for integrative, multi-predictor approaches for more robust forecasting.

The majority of the world's plants rely on animal pollinators for reproduction, making pollination a key ecosystem service for the maintenance of natural and cultivated plant communities. Mutual interactions between plants and pollinators, also called "plant-pollinator networks", are becoming increasingly vulnerable due to the intensification of anthropogenic land use and climate change. Thus, due to the rapid decline of semi-natural grasslands in the Northern Apennines (Italy), we aimed at understanding how the fragmentation of these habitats, the spatial distribution, and the amount of semi- and natural areas surrounding them, could affect species diversity and plant-pollinator networks. Specifically, in the Northern Apennines, we monitored semi-natural grasslands belonging to the EU habitat type 6510 to evaluate the effect of fragmentation on plant and pollinator richness and on the plant-pollinator network. We carried out generalized linear models considering three taxonomical and six network descriptors as response variables and the combinations of grasslands size and isolation, as well as 10 other factors describing landscape composition as explanatory variables. We found a well-structured plant-pollinator network, characterized by a high diversity of both plants and pollinators, with mutual relations marginally specialized, highly affected by habitat fragmentation and the land use of surrounding grasslands. Moreover, large and neighboring patches increased pollinator richness and improved the overall network structure while the occurrence of meadows and shrubs around fragmented patches was important to ensure the continuity of floristic resources. Finally, extensive croplands and agricultural settlements significantly reduced plant and pollinator diversity, favoring generalist (probably invasive) species, which however increased the strength and stability of the network.

The spread of invasive species is a threat to global biodiversity. The Japanese beetle is native to Japan, but alien populations of this insect occur in North America, and recently, also in southern Europe. This beetle was recently included on the list of priority species of European concern, as it is a highly invasive agricultural pest. Thus, in this study, we aimed at (i) assessing its current distribution range, and identifying areas of potential invasion, and (ii) predicting its distribution using future climatic and land-use change scenarios for 2050. We collected species occurrences available on the citizen science platform iNaturalist, and we combined species data with climatic and land-use predictors using a Bayesian framework, specifically the integrated nested Laplace approximation, with a stochastic partial differential equation. We found that the current distribution of the Japanese beetle was mainly, and positively, driven by the percentage of croplands, the annual range of temperature, habitat diversity, percentage of human settlements, and human population density; it was negatively related to the distance to airports, elevation, mean temperature diurnal range, wetlands, and waters. As a result, based on current conditions, the Japanese beetle is likely to occur in 47,970,200 km2, while its distribution will range from between 53,418,200 and 59,126,825 km2, according to the 2050 climatic and land-use change scenarios. We concluded that the Japanese beetle is a high-risk invasive species, able to find suitable conditions for its colonization in several regions around the globe, especially in light of ongoing climatic change. Thus, we strongly recommend strict biosecurity checks and quarantines, as well as regular pest management surveys, in order to reduce its spread.

Knowledge concerning the relative importance of biotic and abiotic factors associated with the long-term settlement of large carnivores in human-dominated landscapes is important for effective species conservation. However, identifying the major drivers of large carnivore occurrences at a continental scale is challenging as several factors can act in concert to affect large carnivore distributions. Thus, we investigated the relationship between the permanent and sporadic occurrences of large carnivores (brown bear, Eurasian lynx, grey wolf and wolverine) and three groups of predictor variables (i.e., landscape attributes, human disturbance and prey availability) on the continental scale in Europe. Specifically, we used generalized linear models (GLMs) and variation partitioning to estimate the independent and cumulative effects of the three predictor groups on large carnivore occurrences. The explained variance for permanent vs. sporadic occurrence was highest for the wolverine (42.8% and 29.7%), followed by the brown bear (20.5% and 16.4%), Eurasian lynx (15.2% and 11.6%) and grey wolf (15.8% and 6.1%). Landscape attributes, such as forest cover, shrub-land cover, altitude and slope, were positively related to the occurrence of grey wolf, brown bear and Eurasian lynx, whereas human disturbance (human population density, distance to roads and to human settlements) was negatively related to wolverine occurrence. For all species, shared effects between landscape attributes and human disturbance accounted for a considerable portion of the explained variation in both permanent and sporadic occurrence, and landscape attributes were generally more important for explaining permanent than sporadic occurrence, except for the wolverine. Prey availability was marginally associated with the permanent occurrence of the grey wolf but we found no statistical effect of prey availability on the occurrence of the other large carnivores. In conclusion, the sporadic occurrence of large carnivores in Europe is more stochastic and less predictable than their permanent occurrence. Landscape attributes and their joint effects with human disturbance are the most important factors related to the recolonization dynamics of large carnivores, although wolverine distributions appear strongly limited by human disturbance itself. Domestic prey availability seems to play a subordinate role in driving the recent distribution dynamics of large carnivores at the continental scale. Thus, our results are relevant also in light of the ongoing recolonization of large carnivores which, in many rural areas, caused concerns among the locals, especially in relation to conflicts with human activities. For these reasons, we stress the need to continue and improve large carnivore monitoring across Europe.

The impact of invasive species is not limited to the loss of biodiversity; it also represents significant threats to agriculture on a global scale. The Japanese beetle Popillia japonica (native to Japan but an invasive agricultural pest in North America) recently occurred in the Po plain (Italy), one of the most cultivated areas in southern Europe. Thus, our aims were to identify (i) the main landscape predictors related to the occurrence of the Japanese beetle and (ii) the areas of potential invasion of the Japanese beetle in the two Northern Italian regions in which this invasive species currently occurs, Piedmont and Lombardy. Specifically, we combined Japanese beetle occurrences available in the citizen science online platform iNaturalist with high-resolution landscape predictors in an ensemble approach and averaged the results of Bayesian generalized linear and additive models developed with the integrated nested Laplace approximation (with stochastic partial differential equation). We found that the occurrence of the Japanese beetle was negatively related to the percentage of broadleaf forests and pastures, while it was positively related to sparse and dense human settlements as well as intensive crops. Moreover, the occurrence of the Japanese beetle increased in relation to the percentage of rice fields until a peak at around 50%. The Japanese beetle was likely to occur in 32.49% of our study area, corresponding to 16,000.02 km(2), mainly located in the Po plain, low hills, and mountain valleys. We stress that the Japanese beetle is a high-risk invasive species in human-dominated landscapes. Thus, we strongly recommend that local administrations quickly enact pest management in order to reduce further spread.

Abstract The natural and seminatural components of agricultural landscapes play a key role in maintaining a high level of biodiversity. Being the Po Valley one of the most human‐dominated and intensively cultivated landscapes in Europe, we investigated the effect of no‐crop habitats on carabid richness and composition and evaluated the role of tree row as corridor for forest carabid dispersion. Carabids were sampled with 70 pitfall traps arranged in 35 sampling plots along three parallel transects (80, 100, and 140 m long) and encompassing five different habitats: tree row, tree row edge, grassland, forest edge, and forest. We found 5,615 individuals belonging to 55 species. Despite the similarity in species richness, all the habitats investigated showed a peculiar and distinct species assemblage. The main distinction was between the "open habitat" cluster composed of grassland and tree row edge and the “forest" cluster composed of forest, tree row, and forest edge. We found that forest species are able to penetrate the grassland matrix up to 30 m from the forest edge and that a distance of no more than 60 m between tree row and forest can allow the passage of up to 50% of the forest species. Beyond this distance, the grassland matrix becomes a barrier, preventing them from reaching other suitable habitats. Our findings confirm the importance of maintaining different types of natural habitats to significantly increase biodiversity in an intensively cultivated agroecosystem and demonstrated the role of linear elements as a corridor and “stepping stones” for many forest species.

Monitoring programs should be based on the measurement of two main pillars for evaluating the conservation status of a species: population size and geographical distribution. To date, the only way reported in the literature to obtain detailed information on L. cervus population size is to use the capture-mark-recapture method. This is an expensive and time-consuming technique that implies physical capture and handling of individuals, which could affect their survival. Therefore, in this study we tested and compared two non-invasive sampling approaches, namely evening walk transects and diurnal tree trunk surveys, to derive accurate abundance estimates by means of N-mixture models in a Bayesian framework. In our study, both methods showed relatively high detection probability (≥56%). However, tree surveys performed better than walk transects (≈80%), especially with the progression of the sampling season. Tree surveys proved to be more effective than walk transects in providing data for an accurate population density estimate (much smaller 95% Bayesian Confidence Intervals). In light of a cost and benefit assessment, the tree survey is undoubtedly more convenient, as well as more effective, as it is more time consuming but less expensive than a walk transect (one operator for 2–3 h vs. two operators for 30 min each). Moreover, it needs fewer expert operators because of the greater proximity to the species, increasing the probability of correctly identifying it, i.e., reducing type I error (false positive or overestimation of counts). For the first time, we applied N-mixture models for estimating population abundance of L. cervus. Overcoming all the limits imposed by the use of the capture-mark-recapture method, in this study we performed a further step forward in the planning of monitoring aimed at the conservation of L. cervus and the evaluation of its demographic trend.

During the periodic moult of the plumage of birds, a fast regrowth of feathers would shorten the time of reduced plumage functionality. However, it has long been known that feather growth-rate is limited and that long feathers take disproportionally longer to grow than small feathers, which has severe consequences on moult duration and the completeness of moult in large birds. The reasons for the limitations of feather-growth must be related to the size and/or functions of the feather follicle, but are largely unknown. Here we measured the size of the feather follicle (taking calamus width as a proxy) and related it to parameters of feather growth (feather growth-rate by mass and by length) and feather structure (feather length, mass, massiveness [mass of feather material per mm feather-length]). We used three independent datasets which allowed for interspecific analyses, and for intraspecific comparisons of differently structured feathers within the framework of biological scaling. We found that the cross-sectional area of the calamus (as a proxy of feather follicle size) was directly proportional to feather growth-rate by mass. Hence, factors acting at a two-dimensional scale (possibly nutrient supply to the growing feather) determines feather growth rate by mass, rather than the linear arrangement of stem cells (in a circular configuration) as had previously been assumed. Feather follicle size was correlated with both feather length and massiveness, hence it seems to be adapted to some extent to feather structure. Feather growth-rate by length was dependent on both the feather material produced per unit time (growth-rate by mass) and the amount of material deposited per unit feather-length. Follicle size not only determines feather growth-rate by mass, but also directly the structural design (shape, number of barbs, etc.) of a feather. Therefore, feather growth-rate is severely constrained by the requirements imposed by the structural feather design.

Abstract Citizen science platforms are increasingly growing, and, storing a huge amount of data on species locations, they provide researchers with essential information to develop sound strategies for species conservation. However, the lack of information on surveyed sites (i.e., where the observers did not record the target species) and sampling effort (e.g., the number of surveys at a given site, by how many observers, and for how much time) strongly limit the use of citizen science data. Thus, we examined the advantage of using an observer‐oriented approach (i.e., considering occurrences of species other than the target species collected by the observers of the target species as pseudo‐absences and additional predictors relative to the total number of observations, observers, and days in which locations were collected in a given sampling unit, as proxies of sampling effort) to develop species distribution models. Specifically, we considered 15 mammal species occurring in Italy and compared the predictive accuracy of the ensemble predictions of nine species distribution models carried out considering random pseudo‐absences versus observer‐oriented approach. Through cross‐validations, we found that the observer‐oriented approach improved species distribution models, providing a higher predictive accuracy than random pseudo‐absences. Our results showed that species distribution modeling developed using pseudo‐absences derived citizen science data outperform those carried out using random pseudo‐absences and thus improve the capacity of species distribution models to accurately predict the geographic range of species when deriving robust surrogate of sampling effort.

Aim Many rare species are dispersal-limited; their colonization capacity can be impacted by land use and climate changes. Most ecological niche models predict the distribution of species under future climate and land use change scenarios without incorporating species-specific dispersal abilities. Here we investigate the effect of climate and land use change on low vagile species accounting for their dispersal capacity and define accessible areas in the future. Location Europe. Taxon Saproxylic beetles. Methods We used the current (2007-2012) occurrences of six endangered saproxylics to develop ecological niche models using current climate and land use conditions. We projected species distributions under four future climate and land use change scenarios to estimate their potential occurrences. Finally, accounting for species-specific dispersal, we limited their distributions to accessible areas in 2040-2050. Results Without accounting for dispersal abilities we found a strong and positive impact of climate change on the distribution of Cerambix cerdo, Cucujus cinnaberinus, Morimus funereus and Rosalia alpina and a positive effect of land use change on the distribution of Lucanus cervus and Osmoderma eremita. When species-specific dispersal was included, we found a strong and positive impact of land use change on the distribution of all the species. In this case climate change had a lower but positive effect on the distribution of C. cerdo, C. cinnaberinus, L. cervus and R. alpina, and a negative effect on the distribution of O. eremita. Main conclusion We found that climate change would promote the expansion of saproxylic beetles only in the unrealistic case of unlimited dispersal. Accounting for dispersal abilities, the expansion of our species would be mainly conditioned by the effect of land use change. Thus, we encourage researchers to combine climate and land use change with dispersal when projecting species distribution under future scenarios to accurately identify areas with fundamental species-specific resources.

While biological distributions are not static and change/evolve through space and time, nonstationarity of climatic and land-use conditions is frequently neglected in species distribution models. Even recent techniques accounting for spatiotemporal variation of species occurrence basically consider the environmental predictors as static; specifically, in most studies using species distribution models, predictor values are averaged over a 50- or 30-year time period. This could lead to a strong bias due to monthly/annual variation between the climatic conditions in which species' locations were recorded and those used to develop species distribution models or even a complete mismatch if locations have been recorded more recently. Moreover, the impact of land-use change has only recently begun to be fully explored in species distribution models, but again without considering year-specific values. Excluding dynamic climate and land-use predictors could provide misleading estimation of species distribution. In recent years, however, open-access spatially explicit databases that provide high-resolution monthly and annual variation in climate (for the period 1901-2016) and land-use (for the period 1992-2015) conditions at a global scale have become available. Combining species locations collected in a given month of a given year with the relative climatic and land-use predictors derived from these datasets would thus lead to the development of true dynamic species distribution models (D-SDMs), improving predictive accuracy and avoiding mismatch between species locations and predictor variables. Thus, we strongly encourage modelers to develop D-SDMs using month- and year-specific climatic data as well as year-specific land-use data that match the period in which species data were collected.

Population divergence could be strongly affected by species' ecology and might not be a direct response to climate-driven environmental change. We tested this in the middle spotted woodpecker (Dendrocoptes medius), a non-migratory, low-dispersal habitat specialist associated with old deciduous forests of the Western Palearctic. We present the first phylogeographic study of this species integrating genetic data (three mitochondrial loci, one autosomal and one Z-linked intron) with species distribution modelling. Based on this species' ecology, we predicted that the middle spotted woodpecker could have colonized its current range from multiple Last Glacial Maximum (LGM) refugia and that strongly structured populations could be expected. Indeed, we discovered a strong genetic divergence between Asian and European populations, with a split estimated at around one million of years ago. This was surprising given only slight intraspecific variation in plumage and morphology. Although there was no significant phylogeographic structure within the Asian and European groups, we cannot exclude the possibility of multiple refugia within either group during the LGM. This has to be further investigated with more extensive geographic sampling and larger number of variable independently evolving markers. Future studies should also investigate potential differences in vocalizations and ecology between the two groups. Lineages showing similar level of genetic differentiation including woodpeckers are often treated as species-level taxa. Comparison of our results with the phylogeographic history of other woodpeckers, suggests that sympatric species with similar life-histories might have idiosyncratic phylogeographic patterns probably resulting from different ecological requirements or historic stochasticity.

Capsule The first European Bird Census Council (EBCC) Atlas of European Breeding Birds has been widely used in scientific publications. Aims To quantify how scientific publications have used data from the first European Bird Census Council (EBCC) Atlas of European Breeding Birds, what the topics of these studies have been, and to identify key aspects in which a second European Breeding Bird Atlas will provide new opportunities for basic and applied science. Methods We searched Google Scholar to find papers published in scientific journals that cited the first atlas. We analysed the contents of a random selection of 100 papers citing this atlas and described the way these papers used information from it. Results The first atlas has been cited in 3150 scientific publications, and can be regarded as a fundamental reference for studies about birds in Europe. It was extensively used as a key reference for the studied bird species. A substantial number of papers re-analysed atlas data to derive new information on species distribution, ecological traits and population sizes. Distribution and ecology were the most frequent topics of studies referring to the atlas, but this source of information was used in a diverse range of studies. In this context, climate change, impact of agriculture and habitat loss were, by order, the most frequently studied environmental pressures. Constraints in the atlas, such as the poor coverage in the east of Europe, the lack of information on distribution change and the coarse resolution were identified as issues limiting the use of the atlas for some purposes. Conclusions This study demonstrates the scientific value of European-wide breeding bird atlases. A second atlas, with its almost complete coverage across Europe, the incorporation of changes in distribution between the two atlases and the inclusion of modelled maps at a resolution of 10 x 10 km will certainly become a key data source and reference for researchers in the near future.

Our aim is to model rare species (with few occurrences) but modelling the distribution of species with few occurrence data and many predictor variables leads to model overfitting. Thus, we use the recently developed ensemble of small models, which showed high predictive accuracy in modelling the distribution of rare species to estimate the current and future distribution of 56 rare (and endangered) saproxylic beetle species. Thus, we stacked predictions from individual species distribution models to derive rare species richness. We used current and five future general circulation models and three representative concentration pathways to test whether the distribution of hotspots for rare species shifts due to climate change under different future scenarios. Moreover, we verified the representativeness of existing protected area systems under future climate conditions in Italy. Specifically, we identified potential hotspots for rare species richness through a cumulative relative frequency distribution function. The current surface covered by hotspots is 50.4% of the study area corresponding to 151,223 km2 (mainly from central to northern Italy). Currently, only 35,124 km2 of rare saproxylic hotspots are covered by protected areas (PAs) and they will decrease by about 2–72% in 2070 depending on the future scenarios considered. Our results confirmed that the shift of the distribution of hotspots for rare species might occur due to climate change under different future scenarios and that the existing PAs system would be inadequate for assuring the conservation of rare saproxylic beetles in Italy under current and future climate conditions.