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Artificial light at night (ALAN) is increasing in extent and intensity across the globe. It has been shown to interfere with animal sensory systems, orientation and distribution, with the potential to cause significant ecological impacts. We analysed the locations of 102 mountain lions (Puma concolor) in a light-polluted region in California. We modelled their distribution relative to environmental and human-disturbance variables, including upward radiance (nearby lights), zenith brightness (sky glow) and natural illumination from moonlight. We found that mountain lion probability of presence was highly related to upward radiance, that is, related to lights within approximately 500 m. Despite a general pattern of avoidance of locations with high upward radiance, there were large differences in degree of avoidance among individuals. The amount of light from artificial sky glow was not influential when included together with upward radiance in the models, and illumination from moonlight was not influential at all. Our results suggest that changes in visibility associated with lunar cycles and sky glow are less important for mountain lions in their selection of light landscapes than avoiding potential interactions with humans represented by the presence of nearby lights on the ground. This article is part of the theme issue Light pollution in complex ecological systems.

The likelihood of a new migratory route emerging is presumably a function of 1) the associated fitness payoff and 2) the probability that the route arises in the first place. It has been suggested that diametrically opposed ‘reverse' migratory trajectories might be surprisingly common and, if such routes were heritable, it follows that they could underlie the rapid evolution of divergent migratory trajectories. Here, we used Eurasian blackcap (Sylvia atricapilla; ‘blackcap') ringing recoveries and geolocator trajectories to investigate whether a recently evolved northwards autumn migratory route – and accompanying rapid northerly wintering range expansion – could be explained by the reversal of each individual's population‐specific traditional southwards migratory direction. We found that northwards autumn migrants were recovered closer to the sites specified by an axis reversal than would be expected by chance, consistent with the rapid evolution of new migratory routes via bi‐axial variation in orientation. We suggest that the surprisingly high probability of axis reversal might explain why birds expand their wintering ranges rapidly and divergently, and propose that understanding how migratory direction is encoded is crucial when characterising the genetic component underlying migration. [ABSTRACT FROM AUTHOR]

Dispersal is a key life‐history trait for most species and is essential to ensure connectivity and gene flow between populations and facilitate population viability in variable environments. Despite the increasing importance of range shifts due to global change, dispersal has proved difficult to quantify, limiting empirical understanding of this phenotypic trait and wider synthesis.Here, we introduce a statistical framework to estimate standardised dispersal kernels from biased data. Based on this, we compare empirical dispersal kernels for European breeding birds considering age (average dispersal; natal, before first breeding; and breeding dispersal, between subsequent breeding attempts) and sex (females and males) and test whether different dispersal properties are phylogenetically conserved.We standardised and analysed data from an extensive volunteer‐based bird ring‐recoveries database in Europe (EURING) by accounting for biases related to different censoring thresholds in reporting between countries and to migratory movements. Then, we fitted four widely used probability density functions in a Bayesian framework to compare and provide the best statistical descriptions of the different age and sex‐specific dispersal kernels for each bird species.The dispersal movements of the 234 European bird species analysed were statistically best explained by heavy‐tailed kernels, meaning that while most individuals disperse over short distances, long‐distance dispersal is a prevalent phenomenon in almost all bird species. The phylogenetic signal in both median and long dispersal distances estimated from the best‐fitted kernel was low (Pagel's λ < 0.25), while it reached high values (Pagel's λ >0.7) when comparing dispersal distance estimates for fat‐tailed dispersal kernels. As expected in birds, natal dispersal was on average 5 km greater than breeding dispersal, but sex‐biased dispersal was not detected.Our robust analytical framework allows sound use of widely available mark‐recapture data in standardised dispersal estimates. We found strong evidence that long‐distance dispersal is common among European breeding bird species and across life stages. The dispersal estimates offer a first guide to selecting appropriate dispersal kernels in range expansion studies and provide new avenues to improve our understanding of the mechanisms and rules underlying dispersal events. [ABSTRACT FROM AUTHOR]

Models are useful tools for understanding and predicting ecological patterns and processes. Under ongoing climate and biodiversity change, they can greatly facilitate decision‐making in conservation and restoration and help designing adequate management strategies for an uncertain future. Here, we review the use of spatially explicit models for decision support and to identify key gaps in current modelling in conservation and restoration. Of 650 reviewed publications, 217 publications had a clear management application and were included in our quantitative analyses. Overall, modelling studies were biased towards static models (79%), towards the species and population level (80%) and towards conservation (rather than restoration) applications (71%). Correlative niche models were the most widely used model type. Dynamic models as well as the gene‐to‐individual level and the community‐to‐ecosystem level were underrepresented, and explicit cost optimisation approaches were only used in 10% of the studies. We present a new model typology for selecting models for animal conservation and restoration, characterising model types according to organisational levels, biological processes of interest and desired management applications. This typology will help to more closely link models to management goals. Additionally, future efforts need to overcome important challenges related to data integration, model integration and decision‐making. We conclude with five key recommendations, suggesting that wider usage of spatially explicit models for decision support can be achieved by 1) developing a toolbox with multiple, easier‐to‐use methods, 2) improving calibration and validation of dynamic modelling approaches and 3) developing best‐practise guidelines for applying these models. Further, more robust decision‐making can be achieved by 4) combining multiple modelling approaches to assess uncertainty, and 5) placing models at the core of adaptive management. These efforts must be accompanied by long‐term funding for modelling and monitoring, and improved communication between research and practise to ensure optimal conservation and restoration outcomes. [ABSTRACT FROM AUTHOR]

Background and Aims It is widely accepted that changes in the environment affect mean trait expression, but little is known about how the environment shapes intra-individual and intra-population variance. Theory suggests that intra-individual variance might be plastic and under natural selection, rather than reflecting developmental noise, but evidence for this hypothesis is scarce. Here, we experimentally tested whether differences in intrinsic environmental predictability affect intra-individual and intra-population variability of different reproductive traits, and whether intra-individual variability is under selection. Methods Under field conditions, we subjected Onobrychis viciifolia to more and less predictable precipitation over 4 generations and 4 years. We analysed effects on the coefficient of intra-individual variation (CVi-i) and the coefficient of intra-population variation (CVi-p), assessed whether the coefficients of intra-individual variation (CsVi-i) are under natural selection and tested for transgenerational responses (ancestor environmental effects on offspring). Key Results Less predictable precipitation led to higher CsVi-i and CsVi-p, consistent with plastic responses. The CsVi-i of all studied traits were under consistent stabilizing selection, and precipitation predictability affected the strength of selection and the location of the optimal CVi-i of a single trait. All CsVi-i differed from the optimal CVi-i and the maternal and offspring CsVi-i were positively correlated, showing that there was scope for change. Nevertheless, no consistent transgenerational effects were found in any of the three descendant generations, which contrasts with recent studies that detected rapid transgenerational responses in the trait means of different plant species. This suggests that changes in intra-individual variability take longer to evolve than changes in trait means, which may explain why high intra-individual variability is maintained, despite the stabilizing selection. Conclusions The results indicate that plastic changes of intra-individual variability are an important determinant of whether plants will be able to cope with changes in environmental predictability induced by the currently observed climatic change. [ABSTRACT FROM AUTHOR]

Global biodiversity is under high and rising anthropogenic pressure. Yet, how the taxonomic, phylogenetic, and functional facets of biodiversity are affected by different threats over time is unclear. This is particularly true for the two main drivers of the current biodiversity crisis: habitat destruction and overexploitation. We provide the first long‐term assessment of multifaceted biodiversity changes caused by these threats for any tropical region. Focussing on larger mammals in South America's 1.1 million km2 Gran Chaco region, we assessed changes in multiple biodiversity facets between 1985 and 2015, determined which threats drive those changes, and identified remaining key areas for all biodiversity facets. Using habitat and threat maps, we found, first, that between 1985 and 2015 taxonomic (TD), phylogenetic (PD) and functional (FD) diversity all declined drastically across over half of the area assessed. FD declined about 50% faster than TD and PD, and these declines were mainly driven by species loss, rather than species turnover. Second, habitat destruction, hunting, and both threats together contributed ~57%, ~37%, and ~6% to overall facet declines, respectively. However, hunting pressure increased where TD and PD declined most strongly, whereas habitat destruction disproportionally contributed to FD declines. Third, just 23% of the Chaco would have to be protected to safeguard the top 17% of all three facets. Our findings uncover a widespread impoverishment of mammal species richness, evolutionary history, and ecological functions across broad areas of the Chaco due to increasing habitat destruction and hunting. Moreover, our results pinpoint key areas that should be preserved and managed to maintain all facets of mammalian diversity across the Chaco. More generally, our work highlights how long‐term changes in biodiversity facets can be assessed and attributed to specific threats, to better understand human impacts on biodiversity and to guide conservation planning to mitigate them. [ABSTRACT FROM AUTHOR]

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Migratory birds spend periods of the year in different locations as a response to seasonal changes in environmental suitability. They are classified as either 'niche‐trackers' or 'niche‐switchers', depending on whether they track or switch environmental conditions throughout the year. However, the relationship between these strategies and their migratory behaviour is still unclear. Here we examine whether migratory European Robins Erithacus rubecula and Eurasian Blackcaps Sylvia atricapilla track environmental conditions between breeding and wintering areas and whether their behaviour differs from that of their sedentary counterparts. We used ringing data for both migratory and sedentary individuals wintering sympatrically in the Iberian Peninsula to assess the environmental conditions relating to their seasonal distributions. We explored seasonal niche‐tracking using two multivariate analyses with alternative sets of predictor variables (landscape and climate) to generate different environmental scenarios. Our results show that migratory individuals track similar climatic conditions throughout their seasonal distributions, whereas sedentary birds cope with great variation in climate over the course of the year. In addition, migratory birds show less seasonal overlap in the landscape structure of their chosen habitats compared with sedentary individuals. These results suggest that there is a trade‐off between, on the one hand, the cost for migrants of travelling long distances and, on the other, the increased flexibility required by sedentary birds if they are to tolerate a wider suite of environmental conditions within their permanent ranges. Given that sedentary populations in the southern Iberian Peninsula seem to be linked to populations of migratory individuals of these two species that started to move northwards after the last glacial cycle, the observed patterns suggest that migrant birds represent a fraction of the southern population that is specialized in the exploitation of a narrower range of environmental conditions. [ABSTRACT FROM AUTHOR]

Summary: Because migrant birds occur in different parts of the world in different seasons, their numbers may be limited by the size of the smallest area they inhabit during the year. In addition, restricted ranges make populations more susceptible to local perturbations such that range size is frequently considered a correlate of species vulnerability. Despite this, little is known about the balance between seasonal ranges in the migrant populations of partially migratory species. These migrants are difficult to segregate from sedentary conspecifics in winter grounds and thus the extent of their ranges is difficult to assess. Here, we studied the extent of potential breeding and wintering ranges of 10 partial migratory passerines moving to winter in the Iberian Peninsula and the Maghreb. After testing migratory connectivity of the individual species, we used niche modelling to calculate the extent of potential breeding and wintering ranges in 1,113 pairs of ring recoveries linking individuals between breeding and wintering localities. The results indicate that most species show migratory connectivity and that all of them show range compression in winter relative to the breeding range, with scores ranging between 19% and 58% (mean 37%) of breeding ranges. We discuss the importance of non-breeding grounds for conserving migratory passerines in the Western Mediterranean Basin, an area under pressure from climate change and agricultural intensification. [ABSTRACT FROM AUTHOR]

Mediterranean woodlands and associated shrub formations of southern Iberia are key habitats for conservation of migratory birds. In some bird species, migratory and sedentary conspecifics meet in these areas during winter, but our understanding of how each population group is distributed over available habitats and the factors that determine their spatial organization are still unclear. This seriously limits our ability to assess their vulnerability to ongoing environmental changes affecting wintering habitats in this region. We used hydrogen isotopic signatures of feathers (δDf) to shed light on the habitat distribution of seasonally sympatric European Robin Erithacus rubecula populations wintering in Campo de Gibraltar that are currently facing a drastic decline. In contrast to previous studies that used morphological methods to distinguish the migratory behaviour of wintering Robins in this area, our isotopic approach revealed that sedentary Robins were not outcompeted upon the arrival of migrants and remained in the woodlands where they reproduce, which agrees with results obtained in other regions. Interestingly, we also found that migratory Robins with a closer breeding origin (higher δDf values) had a higher probability of occupying woodlands than did migrants coming from further away. Overall, our results suggest that the role of breeding origin in shaping the distribution of Robins during winter in Campo de Gibraltar is more relevant than the effects of sex, age or body size, which might facilitate the evolution of local adaptations for the exploitation of each habitat type. [ABSTRACT FROM AUTHOR]