In the current context of ongoing global change, the understanding of how the niches of invasive species may change between different geographical areas or time periods is extremely important for the early detection and control of future invasions. We evaluated the effect of climate and non-climate variables and the sensitivity to various spatial resolutions (i.e. 1 and 20 km) on niche changes during the invasion of Taraxacum officinale and Ulex europaeus in South America. We estimated niche changes using a combination of principal components analyses (PCA) and reciprocal Ecological Niche Modelling (rENM). We further investigated future invasion dynamics under a severe warming scenario for 2050 to unravel the role of niche shifts in the future potential distribution of the species. We observed a clear niche expansion for both species in South America towards higher temperature, precipitation and radiation relative to their native ranges. In contrast, the set of environmental conditions only occupied in the native ranges (i.e. niche unfilling) were less relevant. The magnitude of the niche shifts did not depend on the resolution of the variables. Models calibrated with occurrences from native range predicted large suitable areas in South America (outside of the Andes range) where T. officinale and U. europaeus are currently absent. Additionally, both species could increase their potential distributions by 2050, mostly in the southern part of the continent. In addition, the niche unfilling suggests high potential to invade additional regions in the future, which is extremely relevant considering the current impact of these species in the Southern Hemisphere. These findings confirm that invasive species can occupy new niches that are not predictable from knowledge based only on climate variables or information from the native range.

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Aim The centre–periphery hypothesis predicts that habitat suitability will decrease at the edge of a species’ range, a pattern often questioned by empirical data. Here we explore if habitat suitability decreases southwards and shapes the abundance distribution of rear edge populations of forest birds within the restricted geographical setting of the south‐western Palaearctic. We also test if birds endemic to the area fit more poorly to the latitudinal decrease in habitat suitability due to the putative effect of adaptations to regional conditions. Location North‐western Africa (Morocco). Taxon Passerines (11 species). Methods Bird occurrences were used to model species distribution and line transects were used to estimate bird abundance. Occurrence probabilities provided by species distribution models were used to display the spatial patterning of habitat suitability. Habitat suitability was employed to predict abundance after controlling for the effect of the distance to some regional source areas of forest birds (tree covered large areas). The species were classified as North African endemic according to an updated review of their taxonomic status. Results Habitat suitability decreased southwards, supporting the predicted relationship between ecological and geographical marginality in most species. Abundance was positively correlated with habitat suitability and negatively correlated with distance to source areas. The taxonomic status of birds did not affect the patterns. Main conclusions The southward decrease in habitat suitability predicted by the centre–periphery hypothesis shapes the distribution of rear edge populations of forest birds within the south‐western Palaearctic. As most of these populations are endemic, the results suggest that they track the gradients in isolation within the geographical setting of north‐western Africa. These results support the vulnerability of these isolated, peripheral populations of forest birds to large‐scale environmental changes in a region under the effect of increasing drought and temperature.

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Avian electrocution on power lines is a major conservation issue on a global scale. Electrocution risk models have recently been proposed as an effective alternative to prioritising high‐risk pole retrofitting activities at a large scale. However, existing models ignore the specific features of the power poles (hereafter, poles) supporting the power distribution lines and make the tenuous assumption that pole density and power line length are key factors to assessing the electrocution risk at a large scale. This assumption may be violated in areas with high variations in pole configuration. In this study, we used data on raptors electrocuted on poles to develop a predictive model of raptor electrocution risk throughout an extensive geographical area in north‐western Spain, using boosted regression trees. With the best‐fitting model, we predicted the hazard of a set of 188,741 poles and validated the model predictions with new data collected from the study area. Our model highlights the relevance of combining both habitat and technical features to identify the most dangerous poles for raptors on a large geographical scale. A 9.86% of the total poles evaluated were characterised as high risk for raptors. The model showed good performance in external validation. The new electrocution events were registered at poles with high‐risk values. Synthesis and applications. In this study, we improved the accuracy of the predictive models of raptor electrocution risk for large geographical areas. By incorporating the technical characteristics of the power poles into the models, we achieved a high level of prediction at the power pole level, which is the ultimate correction unit. This will allow electric companies and wildlife managers to specify retrofitting activities of high‐risk power poles for raptors in large geographical areas, thus maximising the effect of investment in the correction of dangerous power poles and conservation of the raptor populations.

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