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Identifying sites that are both important for biodiversity and likely to be heavily affected by anthropogenic pressures in the future is crucial to settle priorities in the implementation of conservation measures, such as the designation of new protected areas. Although assessing the exposure of terrestrial Key Biodiversity Areas to global change would support such identification, it has never been performed to our knowledge. In addition, previous exposure assessments have been limited to few metrics of climate change and have not considered other global change components. Here, we assess the extent to which terrestrial (including inland water) Key Biodiversity Areas are exposed to future climate change and land‐use modifications in 29 countries of the Mediterranean region, and identify countries where additional protection efforts are most needed. To this end, we calculated two local and two regional exposure metrics using projections of climate and land‐use for late 21st century under four scenarios that were used in the sixth assessment report of the Intergovernmental Panel on Climate Change (SSP1‐2.6, SSP2‐4.5, SSP3‐7.0, and SSP5‐8.5). These four exposure metrics were subsequently combined into an exposure index ranking sites from least to most exposed to climate and land‐use changes. We highlight that the most exposed non‐protected Key Biodiversity Areas are located in countries where the protection of this network is lowest (i.e., high number and percentage of non‐protected sites). We also found that Key Biodiversity Areas were overall more exposed than the rest of the study zone and that the sites most in need of conservation actions were similar across future scenarios. Our study reinforces the pressing necessity to strengthen and extend conservation measures in Mediterranean Key Biodiversity Areas, especially in Middle‐East and Maghreb countries whose Key Biodiversity Areas are both at risk to be strongly affected by anthropogenic pressures and insufficiently protected. [ABSTRACT FROM AUTHOR]

Populations of migratory songbirds in western Europe show considerable variation in population trends between species and regions. The demographic and environmental causes of these large-scale patterns are poorly understood. Using data from Constant Effort mist-netting studies, we investigated relationships between changes in abundance, adult survival and seasonal weather conditions among 35 western European populations of eight species of migratory warblers (Sylviidae). We used cross-species and within-species comparisons to assess whether annual variation in survival was correlated with weather conditions during passage or winter. We estimated survival using CJS mark-recapture models accounting for variation in the proportion of transient individuals and recapture rates. Species wintering in the humid bioclimatic zone of western Africa had significantly higher annual survival probabilities than species wintering in the arid bioclimatic zone of Africa (the Sahel). Rainfall in the Sahel was positively correlated with survival in at least some populations of five species. We found substantially fewer significant relationships with indices of weather during the autumn and spring passage periods, which may be due to the use of broad-scale indices. Annual population changes were correlated with adult survival in all of our study species, although species undergoing widespread declines showed the weakest relationships. [ABSTRACT FROM AUTHOR]

Aim As global temperatures have increased, many species distributions have exhibited polewards shifts, a trend that is predicted to continue in future decades. However, the mechanisms underlying such shifts are not well understood. Here we quantify the impact of large-scale variation in temperature on reproductive output within a group of migratory birds to assess the potential for future range changes. Location Western Europe. Methods We use data from captures of 350,000 individual birds, collected under constant effort ringing protocols from 1994-2006, to estimate productivity (percentage of juveniles caught) for seven species of migrant warblers (family Sylviidae) breeding in Europe in relation to spring temperature and latitude by fitting generalized linear mixed models. Results Productivity was highest at mid-latitudes for six of our seven study species and did not change significantly over the study period. Only one species (reed warbler, Acrocephalus scirpaceus) showed increased productivity at northern sites as expected. Six of the seven species also showed evidence for local adaptation, with productivity decreasing as temperatures diverged from the local mean. However, for three of these species the 'optimum' temperature was greater than the local mean temperature at the majority of sites. Main conclusions These results indicate that latitudinal gradients in productivity are likely to influence large-scale abundance patterns, but that adaptation to local climate conditions has the potential to constrain the rate of northward range shifts in many species. [ABSTRACT FROM AUTHOR]

Few studies have examined how life history traits and the climate envelope influence the ability of species to respond to climate change and habitat degradation. In this study, we test whether 18 species-specific variables, related to the climate envelope, ecological envelope and life history, could predict recent population trends (over 17 years) of 71 common breeding bird species in France. Habitat specialists were declining at a much higher rate than generalists, a sign that habitat quality is decreasing globally. The lower the thermal maximum (temperature at the hot edge of the climate envelope), the more negative are the population trends and the less tolerant these species are climate warming, regardless of the thermal range over which these species occur. The life history trait ‘the number of broods per year’ was positively related to recent trends, suggesting that single-brooded species might be more sensitive to advances in food peak due to climate change, as it increases the risk of mistiming their single-breeding event. Annual fecundity explained long-term declines, as it is a good proxy for most other demographic rates, with shorter-lived species being more sensitive to global change: individuals of species with higher fecundity might have too short a life to learn to adapt to directional changes in their environment. Finally, there was evidence that natal dispersal was a predictor of recent trends, with species with high natal dispersal experiencing smaller population declines than species with low natal dispersal. This is expected if the higher the natal dispersal, the larger the ability to shift spatially when facing changes in local habitat or climate, in order to track optimal conditions and adapt to global change. Identifying decline-promoting factors allow us to infer mechanisms responsible for observed declines in wild bird populations facing global change, and by doing so allow for a more pre-emptive approach to conservation planning. [ABSTRACT FROM AUTHOR]

Migration is a widespread strategy that enables animals to escape harsh winter conditions. It has been well documented that migration phenology in birds is changing in response to recent climate warming in the northern hemisphere. Despite the existence of large temporal and geographical scale ringing data on birds in Europe, changes in migration strategies in relation to climate warming have not been well studied, mainly because of a lack of appropriate statistical methods. In this paper, we develop a method that enables us to investigate temporal changes in migration strategies from recoveries of dead ringed birds. We estimated migration probability as the ratio between recovery probabilities of conspecific birds originating from different countries but potentially wintering in the same country. We applied this method to two European thrushes: the entirely migrant redwing Turdus iliacus, and the partially migrant blackbird T. Merula. We tested for an immediate and a 1-year lagged relationship between our migration probability and climatic covariates (i. E. Mean winter temperature in France and the North Atlantic Oscillation). Using ringing-recovery data collected in Finland, Germany, Switzerland and France from 1970 to 1999, we detected contrasting responses in these two species, likely related to their different migratory behaviours. Both species showed a decline in the probability for northern and eastern birds to winter in France. The entirely migratory redwing exhibited a year-to-year plastic response to climate, whereas the decline in the partially migrant blackbird was smooth, suggesting underlying genetic processes. The proposed method, thus, allows us to identify useful indicators of climatic impacts on migration strategies, as well as highlighting differences between closely related species. [ABSTRACT FROM AUTHOR]

The identification of the characteristics of species that make them susceptible or resilient to climate change has been elusive because non-climatic influences may dominate short- and medium-term changes in population and distribution sizes. Here we studied the 2003 French heat wave, during which other confounding variables remained essentially unchanged, with a correlational approach. We tested the relationship between population resilience and thermal range by analysing the responses of 71 bird species to a 6-month heat wave. Species with small thermal ranges showed the sharpest decreases in population growth rate between 2003 and 2004 in locations with the highest temperature anomalies. Thermal range explained the resilience of birds to the heat wave independently of other potential predictors, although it correlated with nest location and broad habitat type used by species. The geographically deduced thermal range appears to be a reliable predictor of the resilience of these endothermic species to extreme temperatures. [ABSTRACT FROM AUTHOR]

Climate change, habitat degradation, and direct exploitation are thought to threaten biodiversity. But what makes some species more sensitive to global change than others? Approaches to this question have relied on comparing the fate of contrasting groups of species. However, if some ecological parameter affects the fate of species faced with global change, species response should vary smoothly along the parameter gradient. Thus, grouping species into few, often two, discrete classes weakens the approach. Using data from the common breeding bird survey in France – a large set of species with much variability with respect to the variables considered – we show that a quantitative measure of habitat specialization and of latitudinal distribution both predict recent 13 year trends of population abundance among 77 terrestrial species: the more northerly distributed and the more specialized a species is, the sharper its decline. On the other hand, neither hunting status, migrating strategy nor body mass predicted population growth rate variation among common bird species. Overall, these results are qualitatively very similar to the equivalent relationships found among the British butterfly populations. This constitutes additional evidence that biodiversity in Western Europe is under the double negative influence of climate change and land use change. [ABSTRACT FROM AUTHOR]

Sea‐level rise (SLR) is expected to cause major changes to coastal wetlands, which are among the world's most vulnerable ecosystems and are critical for nonbreeding waterbirds. Because strategies for adaptation to SLR, such as nature‐based solutions and designation of protected areas, can locally reduce the negative effects of coastal flooding under SLR on coastal wetlands, it is crucial to prioritize adaptation efforts, especially for wetlands of international importance for biodiversity. We assessed the exposure of coastal wetlands important for nonbreeding waterbirds to projected SLR along the Mediterranean coasts of 8 countries by modeling future coastal flooding under 7 scenarios of SLR by 2100 (from 44‐ to 161‐cm rise) with a static inundation approach. Exposure to coastal flooding under future SLR was assessed for 938 Mediterranean coastal sites (≤30 km from the coastline) where 145 species of nonbreeding birds were monitored as part of the International Waterbird Census and for which the monitoring area was delineated by a polygon (64.3% of the coastal sites monitored in the Mediterranean region). Thirty‐four percent of sites were threatened by future SLR, even under the most optimistic scenarios. Protected study sites and study sites of international importance for waterbirds were, respectively, 1.5 and 2 times more exposed to SLR than the other sites under the most optimistic scenario. Accordingly, we advocate for the development of a prioritization scheme to be applied to these wetlands for the implementation of strategies for adaptation to SLR to anticipate the effects of coastal flooding. Our study provides major guidance for conservation planning under global change in several countries of the Mediterranean region. [ABSTRACT FROM AUTHOR]

Thermal adjustment of waterbird communities to climate warming is crucial but hampered by natural habitat conversion, increasing their climatic debt. As it is, in contrast, facilitated in protected areas, assessing the adequacy of the current protected areas network with respect to future climate and land-use changes and identifying priority sites to protect is of major importance. In this study, we assess the thermal adjustment limitations that non-breeding waterbird communities might experience by the end of the 21st century in the Mediterranean region to highlight priorities for wetland protection. Priorities were set by combining the exposure of waterbird communities to natural habitat conversion and climate warming with their thermal specialization. The latter was calculated using winter abundance data of 151 species from 2932 sites of the International Waterbird Census in 21 Mediterranean countries. Exposure was assessed using future projections of temperature and land-use under four CMIP6 scenarios (SSP1–2.6, SSP2–4.5, SSP3–7.0, and SSP5–8.5). We found that strictly protected areas are located in wetlands whose waterbird communities, without protection, would likely experience high limitations in thermal adjustment in the coming decades. This highlights that the location of existing protected areas may effectively support the thermal adjustment of waterbird communities to future climate warming. However, 490 sites considered at risk lack protection, including 32 sites of international importance for waterbirds, stressing the need to strengthen the protected areas network in these sites in priority. Our study provides important guidance for conservation planning in the Mediterranean region to support waterbird responses to climate change. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Volunteer-based standardized monitoring of birds has been widely implemented in Europe and North America. In France, a breeding bird survey is running since 1989 and offers keen birdwatchers to count spring birds annually during 5 min exactly on 10 fix points within a randomly selected square. The first goal of such breeding bird surveys is to measure temporal trends in order to detect possible species declines. Combining annual indices of species sharing ecological affinities or a protected/red list status further provides biodiversity indicators for policy makers. Because the sampling effort is similar among sites, and because the initial selection of monitored sites is random, the temporal trends can be considered representative of national trends, and spatial comparisons of the obtained metrics are possible. Species abundance, community richness but also community specialization and average trophic level can be estimated for each site and each year and further related to the wide range of habitat and landscape characteristics and to agricultural or forestry practices. The large number of sites allows overcoming the opposition between adaptive and passive monitoring, making such schemes fitted to adaptive monitoring. This provides opportunities to determine which type of management or practices favour biodiversity. The comparison of population fate or community dynamics across a wide range of climates and temperatures, e.g. from southern to northern Europe, revealed how European birds are already affected by climate change. Bird communities are shifting northwards, but at a slower rate than temperatures, while bird populations have larger growth rates away from their hot thermal limit. Finally, such large-scale long-term monitoring data on a complete taxonomic group (Aves) is original and offers the opportunity to compare different measures of biological diversity, such as taxonomic, phylogenetic and functional diversity. Such a citizen science scheme is an efficient scientific tool (numerous papers published in international peer-reviewed journals) which is furthermore highly cost-effective, with a reduced permanent staff in a state insitution coordonating the network and analysing the data, while a similar survey conducted by state staff only would cost more than one million euros annually. The future development of bio-economic dynamic models for providing scenarios of sustainable farming and logging to maintain biodiversity will further highlight the necessity of such volunteer monitoring for policy makers and decision planning. Scientific and logistic partnerships could be proposed to help developing such a monitoring scheme in China. [Copyright &y& Elsevier]

Abstract: To develop a complete and informative biodiversity observation system, it is necessary to compare the strengths and limits of various monitoring schemes. In this article, we examine the various advantages of extensively monitoring fine-grained spatial variations of biodiversity, where the prominent traits of many species within a community (abundance, phenology, etc.) are regularly recorded at numerous sites over a large territory, usually via human observation networks. Linking these variations with environmental factors sheds lights on the major mechanisms leading to changes in biodiversity, thus increasing our knowledge of macroecology and community ecology. This extensive monitoring allows us to assess diffuse effects, contributing to the sound use of the precautionary principle. Combined with site-focused monitoring, information gathered from extensive monitoring provides the raw material necessary to build biodiversity scenarios. [Copyright &y& Elsevier]