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There is an intense interest in long-term trends of species abundance that may reflect, for example, climate change or conservation actions. Less well studied are patterns in the magnitude of inter-annual variability in abundance across large spatial scales. We collated abundance time-series for 133 nesting sites across the globe of the seven sea turtle species. Inter-annual variability in nest numbers was lowest in loggerhead turtles (Caretta caretta), Kemp's ridley (Lepidochelys kempii) and flatback turtle (Natator depressus) and highest in green turtles (Chelonia mydas), likely reflecting their lower trophic position compared to other species and hence tighter coupling of food availability to environmental conditions each year. The annual number of nests in green turtles could vary by 60-fold between successive years. We identified regional patterns in the magnitude of inter-annual variability in green turtle nest numbers, variability being highest for nesting beaches around Australia and lowest in the western Indian Ocean and equatorial Atlantic. These regional patterns are likely linked to corresponding patterns of environmental variability with, for example, areas subjected environmental extremes as part of the El Nino Southern Oscillation (ENSO) showing high inter-annual variability in nest numbers. [ABSTRACT FROM AUTHOR]

Marine protected areas (MPAs) represent the main tool for halting the loss of marine biodiversity. However, there is increasing evidence concerning their limited capacity to reduce or eliminate some threats even within their own boundaries. Here, we analysed a Europe-wide dataset comprising 31,579 threats recorded in 1692 sites of the European Union's Natura 2000 conservation network. Focusing specifically on threats related to marine species and habitats, we found that fishing and outdoor activities were the most widespread threats reported within MPA boundaries, although some spatial heterogeneity in the distribution of threats was apparent. Our results clearly demonstrate the need to reconsider current management plans, standardise monitoring approaches and reporting, refine present threat assessments and improve knowledge of their spatial patterns within and outside MPAs in order to improve conservation capacity and outcomes. Unlabelled Image • Recreational activities and fishing are the main threats affecting European MPAs. • The majority of the threats occur/act both inside and outside the boundaries of the MPAs. • There is heterogeneity in the distribution of threats across European countries. • Standardised monitoring and assessments are needed to improve conservation capacity and outcomes. [ABSTRACT FROM AUTHOR]

As climate-related impacts threaten marine biodiversity globally, it is important to adjust conservation efforts to mitigate the effects of climate change. Translating scientific knowledge into practical management, however, is often complicated due to resource, economic and policy constraints, generating a knowledge-action gap. To develop potential solutions for marine turtle conservation, we explored the perceptions of key actors across 18 countries in the Mediterranean. These actors evaluated their perceived relative importance of 19 adaptation and mitigation measures that could safeguard marine turtles from climate change. Of importance, despite differences in expertise, experience and focal country, the perceptions of researchers and management practitioners largely converged with respect to prioritizing adaptation and mitigation measures. Climate change was considered to have the greatest impacts on offspring sex ratios and suitable nesting sites. The most viable adaptation/mitigation measures were considered to be reducing other pressures that act in parallel to climate change. Ecological effectiveness represented a key determinant for implementing proposed measures, followed by practical applicability, financial cost, and societal cost. This convergence in opinions across actors likely reflects long-standing initiatives in the Mediterranean region towards supporting knowledge exchange in marine turtle conservation. Our results provide important guidance on how to prioritize measures that incorporate climate change in decision-making processes related to the current and future management and protection of marine turtles at the ocean-basin scale, and could be used to guide decisions in other regions globally. Importantly, this study demonstrates a successful example of how interactive processes can be used to fill the knowledge-action gap between research and management. • Knowledge-action gap on marine turtle conservation under climate change was explored. • Researchers and conservation managers from 18 Mediterranean countries participated. • Participant perceptions largely converged despite different expertise or experience. • The risk to hatchling sex ratios and loss of suitable nesting sites were highlighted. • Legislative actions ranked scores regarding support to adaptation/mitigation measures. [ABSTRACT FROM AUTHOR]

For the past two decades, the need to shield strategic maritime interests, to tackle criminality and terrorism at or from the sea and to conserve valuable marine resources has been recognized at the highest political level. Acknowledging and accounting for the interplay between climate change, the vulnerability of coastal populations and the occurrence of maritime criminality should be part of any ocean governance process. Still, given the complex interactions between climate change and socio-economic components of the marine realm, it has become urgent to establish a solid methodological framework, which could lead to sound and effective decisions. We propose that any such framework should not be built from scratch. The adaptation of well tested, existing uncertainty-management tools, such as Cumulative Effect Assessments, could serve as a solid basis to account for the magnitude and directionality of the dependencies between the impacts of climate change and the occurrence of maritime criminality, offering spatial explicit risk evaluations. Multi-Criteria Decision Making could then be employed to better and faster inform decision-makers. These mechanisms could provide a framework for comparison of alternative mitigation and adaptation actions and are essential in assessing responses to tackle maritime crime in the context of climate change. [ABSTRACT FROM AUTHOR]

To effectively tackle the challenge of biological invasions through targeted strategies and mitigation measures, managers and policy makers require adequate reporting and flow of information. For this reason, the European ‘Natura 2000’ network of protected areas, which is the main conservation tool of the European Union, is supported by a standardized database. All threats to biodiversity are supposed to be reported in sufficient detail through that database. We compared the reported threats by ‘invasive non-native species’ in the Natura 2000 database with the actual cumulative impacts of invasive alien species on marine habitats in the Mediterranean using the CIMPAL index (Cumulative IMPacts of invasive ALien species). CIMPAL estimates cumulative impact scores on the basis of the distributions of invasive species and ecosystems, and both the documented magnitude of negative ecological impacts and the strength of such evidence. We showed that the threat of invasive alien species is substantially under-reported in the official documentation. Specifically, among the 1455 marine sites of the network, no threat was officially reported in one third of the sites. The threat of biological invasions was only reported in 154 sites, despite negative impacts by invasive alien species being predicted for 98% of all sites when using CIMPAL. In fact, in the subgroup of sites where no threats have been officially reported, the impacts predicted by CIMPAL were the highest. Such, inadequate and insufficient reporting of threats in the Mediterranean marine Natura 2000 sites presents a significant obstacle to the flow of accurate information needed to support conservation policies and marine management. [ABSTRACT FROM AUTHOR]

The Natura 2000 network forms the cornerstone of the biodiversity conservation strategy of the European Union and is the largest coordinated network of protected areas (PAs) in the world. Here, we demonstrated that the network fails to adequately cover the marine environment and meet the conservation target of 10% set by the Convention on Biological Diversity. The relative percentage of marine surface cover varies significantly among member states. Interestingly, the relative cover of protected seascape was significantly lower for member states with larger exclusive economic zones. Our analyses demonstrated that the vast majority (93%) of the Natura 2000 sites that cover marine waters include both a terrestrial and a marine component. As a result, the majority of the protected surfaces is adjacent to the coastline, and decreases offshore; only 20% of Natura marine PAs is at depths >200 m. The lack of systematic planning processes is further reflected by the great variability in the distances among protected sites and the limited number of shared Natura sites among member states. Moreover, <40% of the marine sites have management plans, indicating the absence of active, or limited management in most sites. This work highlights the gaps in coverage and spatial design of the European conservation network in the marine environment, and raises questions on the unevenly treatment of marine vs. terrestrial areas. [ABSTRACT FROM AUTHOR]

The article presents a study that examined the population status of seven species of sea turtle globally. Topics discussed include upward trends in 12 regional management units (RMUs) versus downward trends in five RMUs, the prevalence of more upward than downward trends in the individual time series and the finding that even small sea turtle populations have the capacity to recover.

For species with temperature-dependent sex determination (TSD) there is the fear that rising temperatures may lead to single-sex populations and population extinction. We show that for sea turtles, a major group exhibiting TSD, these concerns are currently unfounded but may become important under extreme climate warming scenarios. We show how highly female-biased sex ratios in developing eggs translate into much more balanced operational sex ratios so that adult male numbers in populations around the world are unlikely to be limiting. Rather than reducing population viability, female-biased offspring sex ratios may, to some extent, help population growth by increasing the number of breeding females and hence egg production. For rookeries across the world (n = 75 sites for seven species), we show that extreme female-biased hatchling sex ratios do not compromise population size and are the norm, with a tendency for populations to maximize the number of female hatchlings. Only at extremely high incubation temperature does high mortality within developing clutches threaten sea turtles. Our work shows how TSD itself is a robust strategy up to a point, but eventually high mortality and female-only hatchling production will cause extinction if incubation conditions warm considerably in the future. [ABSTRACT FROM AUTHOR]

Highlights: [•] We assess the importance of patches of different quality in bear's movement pattern. [•] Habitat suitability and graph based movement models were combined. [•] Less suitable patches are critical for facilitating movement and connectivity. [•] Studies on movement should consider the importance of the intervening matrix. [•] Unexpected conservation priorities could be raised by combining different models. [Copyright &y& Elsevier]

Highlights: [•] 25% sea turtle nesting sites are in PAs, of which 78% are MPAs. [•] 87% of sites are in the tropics, mainly hosted by developing countries. [•] Countries provide highly variable protection coverage of different turtle species. [•] 67% out of 57% nesting sites in PAs with IUCN ratification receive high protection. [•] Global species resilience needs representative species- and country-level PA coverage. [ABSTRACT FROM AUTHOR]

Human health and well-being presuppose environmental quality. Several studies have documented the indicative role of land use types in environmental quality. However, the exact role of land use composition on disease distribution has remained scientifically vague. We assessed the congruence of diseases’ distribution with land use composition, focusing on high environmental quality areas, defined as tranquil areas with view to indicating places offering well-being. Landscape composition is linked to the presence of diseases across 51 prefectures of Greece. Agricultural and natural land use types proved to be the main drivers of disease distribution. Tranquility demonstrated a strong negative correlation with population density, thus could be considered as a quantitative spatial index of life-quality. We concluded that the landscape context affects the dominance of diseases’ patterns. Special emphasis should be put on the role of tranquil areas in human health and the relative environmental health policies. [ABSTRACT FROM PUBLISHER]

Highlights: [•] We aimed to unravel the criteria used for prioritizing Greek Natura 2000 sites. [•] Management history criteria (e.g. management actions) were the critical components of the selection process. [•] The Greek prioritized sub-network was not considered as optimal based on ecological factors. [•] Socioeconomic drivers were undervalued in the prioritization process. [•] Conservation effort on sites consistently scoring high for all criteria is important. [Copyright &y& Elsevier]

Climate and land use changes are major threats to biodiversity. To preserve biodiversity, networks of protected areas have been established worldwide, like the Natura 2000 network across the European Union (EU). Currently, this reserve network consists of more than 26000 sites covering more than 17% of EU terrestrial territory. Its efficiency to mitigate the detrimental effects of land use and climate change remains an open research question. Here, we examined the potential current and future geographical ranges of four birds of prey under scenarios of both land use and climate changes. By using graph theory, we examined how the current Natura 2000 network will perform in regard to the conservation of these species. This approach determines the importance of a site in regard to the total network and its connectivity. We found that sites becoming unsuitable due to climate change are not a random sample of the network, but are less connected and contribute less to the overall connectivity than the average site and thus their loss does not disrupt the full network. Hence, the connectivity of the remaining network changed only slightly from present day conditions. Our findings highlight the need to establish species-specific management plans with flexible conservation strategies ensuring protection under potential future range expansions. Aquila pomarina is predicted to disappear from the southern part of its range and to become restricted to northeastern Europe. Gyps fulvus, Aquila chrysaetos, and Neophron percnopterus are predicted to locally lose some suitable sites; hence, some isolated small populations may become extinct. However, their geographical range and metapopulation structure will remain relatively unaffected throughout Europe. These species would benefit more from an improved habitat quality and management of the existing network of protected areas than from increased connectivity or assisted migration. [ABSTRACT FROM AUTHOR]

Abstract: Nowadays that biodiversity monitoring is a legal obligation in many countries, monitoring implementation still lags behind the needs for efficient conservation. This is mainly due to three limiting factors that are rarely available for an exhaustive diversity survey, i.e. time consuming, expensive and demands high level of expertise. We propose an alternative monitoring scheme based on the higher taxon approach. This approach allows rapid tracking of biodiversity changes and the utilization of data collected by non-expert volunteers. Here we show, for the first time, that temporal changes in genera or family richness are strongly correlated to, and have similar spatial pattern characteristics as changes in species richness for the breeding birds in New York State. Changes in genera richness proved more reliable in predicting changes in species richness than changes in family richness. [Copyright &y& Elsevier]

Aim We investigated the biogeographical patterns of phytoplankton, zooplankton and fish in freshwater ecosystems. We tested whether spatial distance or environmental heterogeneity act as potential factors controlling community composition. Location Northern and central Greece, eastern Mediterranean. Method Data on 310 phytoplankton, 72 zooplankton and 37 fish species were collected from seven freshwater systems. Species occurrence data were used to generate similarity matrices describing community composition. We performed Mantel tests to compare spatial patterns in community composition of phytoplankton, zooplankton and fish. Next, we examined the correlation between geographical distance and the degree of similarity in community composition. The analysis was repeated for different taxonomic, trophic and size-based groups of the microorganisms studied. We assessed different environmental variables (topographic and limnological) as predictors of community composition. Results Phytoplankton community composition showed a strong positive correlation with environmental heterogeneity but was not correlated with the geographical distance between systems. Zooplankton community composition was unrelated to geographical distance and was only weakly correlated with environmental variables. In contrast, fish community similarity decayed significantly with distance. We found no relationship along all pairwise comparisons of the compositional matrices of the three groups. The pairwise comparisons of the different taxonomic, trophic and size-based groups of the microorganism communities studied were in accordance with the results for the entire microorganism community. Main conclusions Our results support the proposition that the biogeography of microorganisms does not demonstrate a distance–decay pattern and further suggest that, in reality, the drivers of distribution depend on the specific community examined. In contrast, the biogeography of macroorganisms was affected by geographical distance. These differences reflect the dispersal abilities of the different organisms. The microorganisms exhibit passive dispersal through the air, with local environmental conditions structuring their community composition. On the other hand, for macroorganisms such as fish, the terrestrial environment could pose barriers to their dispersal; with fish structuring distinctive communities over greater distances. Overall, we suggest that the biogeography of freshwater phytoplankton and zooplankton reflects contemporary environmental conditions, while the biogeographical patterns for fish inhabiting the same systems are related to factors affecting their dispersal ability. [ABSTRACT FROM AUTHOR]

1. Halting biodiversity loss, a major environmental challenge, relies on the understanding of species richness patterns. The assessment of species richness is often hampered by limited taxonomic knowledge and the general dearth of trained systematists. Research has shown that we can predict the number of species in a community by the number of higher order taxonomic units present. Here, we test whether we need to know all the genera, families or orders in order to do so. Further, the number of common species in a region is a good predictor of total richness and we test if this predictability translates to using higher taxa. 2. We used data from 240 sites from the Natura 2000 network of protected areas in Greece, including 5148 plant species and subspecies, which are grouped in 1113 genera 174 families and 56 orders. We correlated species richness with the number of common genera, families or orders present. The analysis was repeated using the number of the most speciose higher orders instead of the most common. 3. We found that we do not need to know all higher order taxa present, in order to predict species richness. If we know how many out of the 30 most common orders are present, we can reliably predict the number of species. Similar results were obtained if we know how many of the 60 most common families or 200 most common genera are present. 4. Equally good results were obtained using the same numbers of the most speciose higher orders. 5. Synthesis and applications. Our analysis demonstrates that species richness can be predicted from the number of common or more speciose genera, families and orders present. These predictions hold without complete sampling of these higher taxa. The implication is that we need only limited systematic knowledge, resources and effort in order to predict species richness. Assuming these findings hold in other taxonomic groups and in other regions, we argue that the uncertainty introduced by limited knowledge of the systematics ... [ABSTRACT FROM AUTHOR]

Abstract: The sea surface temperature (SST) in loggerhead turtle breeding areas affects the species reproductive biology. Less is known about the effects of changes in SST in the species foraging grounds. We used nesting data for the Mediterranean loggerhead turtle population breeding on the Greek island of Zakynthos to study the effect of SST in the population foraging grounds upon the initiation of nesting and the number of clutches laid. We found that the climatic conditions (SST) in the foraging grounds affected the population nesting phenology in the short term (i.e. within the same year); warmer years triggered an earlier onset of nesting. However, the effect of foraging grounds SST upon nesting is comparatively less important than the local conditions at the nesting ground. Although nesting phenology seems to depend on current''s year foraging grounds SST the number of nests in our study rookery were negatively correlated with SSTs recorded 2 years prior nesting, with higher SST leading to fewer nests. From this point of view, climate change at the foraging grounds may influence the reproductive phenology of loggerheads. [Copyright &y& Elsevier]

Conservation measures applied to sea turtle nesting sites have a beneficial effect on population trends and dynamics. Such measures aim to protect nesting females, increase nesting success (proportion of female emergences resulting in nests) and/or to improve hatching and hatchling emergence success. However, taking into account financial and time constrains it is important to identify those measures that have the most positive impact on the sea turtle population. The aim of this paper is to assess and compare the relative importance of the different factors that may influence the efficiency of conservation actions and to investigate which factors, those associated with decreased nesting success, or others leading to higher embryonic and hatchling mortality have a higher impact on overall hatchling recruitment. We developed a model that simulates the nesting activity of sea turtles. For model parameterization, we used data collected from nesting sites of the loggerhead sea turtles (Caretta caretta) in the Eastern Mediterranean. We conducted a series of simulations by simultaneously changing model input parameters. The results of the model illustrate that an increase in hatchling recruitment success (i.e., hatching and hatchling emergence success) would have a more positive effect on overall hatchling production than a similar in nesting success. Our analysis further suggests that changes in hatchling recruitment success even at a single site, could have an important impact on overall hatchling production of the rookery. [ABSTRACT FROM AUTHOR]

The description of the landscape is based on the visualization of geographic features and the representation of their attributes. Although sound is a major component of any environment, its cartographic representation is limited mainly on noise mapping and in urban or sub-urban areas. Soundscape is a term that describes the acoustic relation between the environment and the individual in a landscape context, considering all kinds of interactions between space, sound and humans. The representation of the soundscape at a spatial level would support many applications such as geographic analysis, ecosystem evaluation, environmental education, landscape management, urban or rural planning and protection of sonic particularities. This paper proposes a methodology for the mapping of both quantitative and qualitative attributes of a rural soundscape, which is described through the study of the acoustic environment around a protected wetland in Greece. [ABSTRACT FROM AUTHOR]

Abstract: Global climate change is likely to have an important influence on the phenology, behaviour and population dynamics of many species. We investigate climatic related changes in the breeding phenology of Mediterranean loggerhead marine turtles Caretta caretta over a 19 year period and the potential relationship between these changes and reproductive success and performance. We found that the studied population has experienced fluctuating sea surface temperatures (SST) with an increasing trend during the last century. With increasing spring SST there is a trend towards earlier nesting. However, there is no significant relationship between SST and nesting season, defined as the duration between the first recorded emergence and the last nest laid. Our analyses indicate that marine turtles display phenological changes, and thus maintain favorable thermal conditions at the nesting sites. Furthermore, increasing spring SST was correlated with decreasing clutch size and increasing hatching success that resulted in an apparent lack of correlation between SST and hatchling production. This apparent independence might be misleading since it only holds for a limited range of SST values. Thus, if we estimate the effect of climate change on loggerhead population growth as neutral, based on the apparent independence between SST and total number of hatchlings, we will be underestimating the population extinction risk. [Copyright &y& Elsevier]

Abstract: A critical issue in conservation biology is the establishment of a strong relationship between species richness and a surrogate index. Such a relationship could provide the basis for the establishment of cost effective and easy to monitor methods for measuring biodiversity, providing an alternative for the prioritization of sites for conservation. We found that richness of species of conservation interest could reliably be predicted from the richness of higher order taxa, such as genus and family, in amphibians, reptiles, birds and mammals. Furthermore, the networks of reserve sites selected based upon the richness of genera or families were as effective in including species diversity, as the ones selected based upon species richness. [Copyright &y& Elsevier]

In sea turtle studies, population trend assessments are primarily based on monitoring of beach nesting. Annual nesting abundances are usually estimated by dividing the total number of nests laid during a season by the mean number of clutches deposited annually by nesting turtles, termed clutch frequency. The estimated numbers of annual nester are used for drawing population trends. In the present study, we evaluate the potential effect of individual variability in clutch frequency and successful nest construction, in estimating annual nesting abundance and nesting population trends. We estimate annual nesting abundance and trends by using constant values of clutch frequency. We further develop a stochastic model that simulates breeding performance as an individual based process to produce estimates of annual female abundances. As the next step, we draw population trends by using abundance estimates produced by the model. Our results indicate that nesting abundance estimations are highly affected by stochasticity in nesting behavior. Long term nesting population trends followed annual fluctuations in nester abundance, leading to a great variability in the produced patterns. Our results indicate that population trend estimations which are based on observed numbers of females nesting annually and mean values of clutch frequency are unreliable due to the exclusion of stochastic events that increment nesting performance, thus should be viewed with increased caution. We conclude that more data are needed to be collected in order to produce accurate estimates of sea turtle nesting population tends. [ABSTRACT FROM AUTHOR]

In an attempt to identify the critical threats to avian biodiversity in Greece we present and analyse a data set of the birds received at a rehabilitation centre, During a 10-year period (1996-2005) a total of 21,190 birds were admitted to the Hellenic Wildlife Hospital from through- out Greece. Our results indicate that shooting is by far the most important threat to birds in Greece, followed by accidents. Although greater numbers of shot birds were received during the autumn and winter months, when hunting is allowed, birds were received year-round. Birds were received from all areas of Greece, with the highest number received during the summer months. The high number of shot birds received during the months in which hunting is prohibited demonstrates the lack of law enforcement. We argue the need for direct political decisions concerning the enforcement of existing regulations on hunting. Decision makers and managers could use the findings of our study to re-evaluate and design conservation policy in Greece, including reduction of the hunting period and restriction on hunting activities. [ABSTRACT FROM AUTHOR]

Abstract: Effective conservation of wildlife species relies on our ability to recognize interactions among critical life stages, leading to the design of the appropriate protection measures. We developed an individual based model to analyze the variability of extinction probabilities as a result of interacting mortalities at different life stages of a sea turtle population. We conducted several simulation with different combinations of mortality rates for both terrestrial stages (i.e. egg and hatchling), and also for all marine stages of the species. To test and assess the implication of the numerous simulation sets produced by the fluctuating survival rates, counter plots were employed. The results of the simulation analysis show that the pelagic stage has a significant effect on population persistence. It is also apparent that increased survival of the first year cohort could to some extent be beneficial for the population. The need for additional demographic data and a better understanding of the behavioral and biological processes is highlighted. [Copyright &y& Elsevier]

Abstract: The sandy beaches of Zakynthos Island support the largest single nesting aggregation in the Mediterranean Region of the endangered loggerhead turtle Caretta caretta. The present study attempts to determine possible correlations between a series of habitat variables and nest site selection. Nesting activities, including total and nesting emergences were examined in response to the recorded biotic and abiotic variables. The results of the analysis indicate that beach width is the most critical habitat variable affecting nest site selection. Further analysis of nesting performance implies that sea turtles use multiple environmental cues for nest site selection during the different steps of the nesting processes such as emergence from the surf and nesting. Nevertheless, we caution that a detailed study needs to be conducted over a more extensive period of time to verify these suggestions. [Copyright &y& Elsevier]

Marine turtles show great variability in annual somatic growth and reproductive performance. Fluctuated environmental conditions are closely linked with reproduction, while recent empirical information suggests the existence of a density dependent effect on somatic growth. We developed an individual based model (IBM) to simulate the effects of a varying environment on population dynamics. A density dependent effect on the age at maturity and re-nesting patterns was also examined. The model depicts units as individual animals, aggregated groups and sets of classes to explicitly incorporate behavioral and biological features of species life history. Biological features and procedures of the simulated population were modeled using parameters for the green turtle species (Chelonia mydas) derived from the literature. Temporal variability on reproductive performance was included by considering autocorrelated and randomly sequenced years indicating good and bad conditions. The analysis indicated that temporal variability could have a significant effect on population persistence. Probability of extinction varied according to fluctuated times of age at maturation and re-nesting intervals. Density dependence as an additional form of temporal variability has also resulted in an increased proportion of extinction in the simulated populations. We conclude that modelling sea turtle population dynamics by the use of IBM could provide some critical insights into population dynamics, overcoming difficulties that arise from the incomplete knowledge of several aspects of species life history. We further suggest some priorities for future research at both the empirical and theoretical level. [Copyright &y& Elsevier]

Climate plays a major role in shaping biodiversity patterns over time and space, with ongoing changes leading to the reorganization of ecosystems, which challenges conservation initiatives. Identifying areas that could serve as possible climate change refugia for future biodiversity is, thus, critical for both conservation and management. Here, we identify potential future climatic refugia within the Euro‐Mediterranean biome, which is a global biodiversity hotspot, while accounting for multiple emission climate change projections over the next 50 years. We developed two metrics of climatic variability: temporal stability and spatial heterogeneity. We then used a systematic conservation planning approach to identify climate‐based priority areas. While we used a climate‐based, species‐neutral methodology, we deliberately implemented low climatic velocity thresholds, so that the identified climatic refugia would even be compatible with the needs of species with low dispersal capacity, such as plants. Our projections showed that future climatic refugia would be more frequently observed in mid‐altitudes, for gradients with steep elevations, and mainly in the eastern part of the Euro‐Mediterranean biome, with possible conflicts with existing land uses and future conservation implications. Climatic, land use, and topography results indicated that only a limited number of refugia would be hosted by high elevation habitats (>1500 m), raising possible concerns about the biodiversity of Mediterranean mountain regions. Our analyses show that the current network of protected areas captures future climatic refugia disproportionally, despite their importance for safeguarding present and future biodiversity in the Mediterranean. Key climatic refugia could limit the impacts of future climate change on biodiversity in mid‐altitude and mountainous regions, and should be included in management guidelines for a climate‐ready conservation design in the Mediterranean biome. [ABSTRACT FROM AUTHOR]

While polyandry in sea turtles is indicated through multiple‐paternity analyses of offspring, confirmed observations of the same female mating with multiple males are extremely challenging to obtain. To contribute to this discussion, we analysed a long‐term photo‐identification database (>20 years) of adult male and female loggerhead sea turtles frequenting the breeding area of Zakynthos, Greece, Mediterranean. A total of 38 records of mating individuals within and across seasons were assimilated via field surveys and citizen science records between 2003 and 2020. For one female, we recorded it mating with two different males within a 5.5‐h interval on the same day in 2015. This observation constitutes the first direct evidence of polyandry in sea turtles, in addition to highlighting the potential for photo‐identification to contribute information on less well‐known aspects of sea turtle biology, such as validating outputs of genetic studies. [ABSTRACT FROM AUTHOR]

Anticipating and mitigating the impacts of climate change on biodiversity requires a comprehensive understanding on key habitats utilized by species. Yet, such information for high mobile marine megafauna species remains limited. Here, we compile a global database comprising published satellite tracking data (n = 1035 individuals) to spatially delineate foraging grounds for seven sea turtle species and assess their thermal stability. We identified 133 foraging areas distributed around the globe, of which only 2% of the total surface is enclosed within an existing protected area. One-third of the total coverage of foraging hotspots is situated in high seas, where conservation focus is often neglected. Our analyses revealed that more than two-thirds of these vital marine habitats will experience new sea surface temperature (SST) conditions by 2100, exposing sea turtles to potential thermal risks. Our findings underline the importance of global ocean conservation efforts, which can meet climate challenges even in remote environments. A global study reveals 133 sea turtle foraging hotspots, with only 2% under current protection. One-third is situated in high seas and two-thirds will face new sea surface temperatures by 2100, stressing the need for comprehensive ocean conservation. [ABSTRACT FROM AUTHOR]

In the face of environmental change, high-quality and fine-scale information is essential in order to monitor the highly dynamic environments on land and sea. While traditional approaches to data collection face a number of practical limitations, advanced technologies could supplement and further improve our efforts. Taking sea turtles as a modeling organism, we present a novel methodological framework for monitoring species by means of advanced technologies, including Unmanned Aerial Vehicles coupled with image and temperature sensors. Diverse monitoring protocols were refined through pilot studies conducted in both terrestrial and nearshore sea turtle habitats. Our approach focuses on the collection of information for critical biological parameters concerning species reproduction and habitat use, following the complex life cycle of the species. Apart from biological information, our framework encompasses also the collection of information on crucial environmental factors that might be changing due to current and future human-derived pressures, such as beach erosion and temperature profile, as well as highly important human activities such as recreational use within nesting beaches that could undermine habitat quality for the species. This holistic and standardized approach to monitoring using advanced technologies could foster our capacity for conservation, resolving difficulties previously addressed and improving the collection of biological and environmental data in the frame of an adaptive management scheme. [ABSTRACT FROM AUTHOR]

Freshwater ecosystems are threatened worldwide, with 1/3 of freshwater species being under extinction risk. Yet, systematic conservation planning has received little attention as a means to prioritize freshwater conservation areas. Here, we develop a comprehensive approach to spatially delineate key areas for freshwater conservation across Europe, considering directed-connectivity, climate change and human-related disturbances. We assess the adequacy of the current reserve network in protecting European freshwater ecosystems and provide guidelines for expansion. We conducted 13 prioritization scenarios for 18,300 sub-basins across Europe, accounting for the distribution of 1,668 freshwater species. Connectivity properties, metrics of climatic stability and human induced pressures were incorporated into the spatial prioritization framework. We highlight the critical importance of specific regions in Central and Southern Europe, the Mediterranean Basin, and parts of the Balkan Peninsula for future freshwater conservation efforts. However, our analysis also reveals the complete inadequacy of the current reserve network, as protected sub-basins only cover 4 % of the study area and encompass on average only 3 % of freshwater species distributions. In contrast, expanding current reserves to cover the top 17 % of high priority areas across Europe could substantially improve the overall coverage of species distributions, reaching an average of 61.5 % for all freshwater species and even exceeding 93.1 % for species of conservation interest (critically endangered, endangered and vulnerable species). The priority freshwater conservation network derived from the analysis provides specific spatial recommendations to help achieve conservation goals if the current reserve network is appropriately expanded. • Freshwater species are at risk worldwide and conservation planning is overlooked. • A new comprehensive approach prioritizes key areas for European freshwaters. • Critical regions for conservation exist in Central Europe and the Mediterranean. • Current reserves are inadequate covering only 4 % of Europe's freshwater ecosystems. • Expanding reserves can result in a 20-fold increase in species coverage within PAs. [ABSTRACT FROM AUTHOR]

Rapid anthropogenic climate change is driving threatened biodiversity one step closer to extinction. Effects on native biodiversity are determined by an interplay between species' exposure to climate change and their specific ecological and life‐history characteristics that render them even more susceptible. Impacts on biodiversity have already been reported, however, a systematic risk evaluation of threatened marine populations is lacking. Here, we employ a trait‐based approach to assess the risk of 90 threatened marine Mediterranean species to climate change, combining species' exposure to increased sea temperature and intrinsic vulnerability. One‐quarter of the threatened marine biodiversity of the Mediterranean Sea is predicted to be under elevated levels of climate risk, with various traits identified as key vulnerability traits. High‐risk taxa including sea turtles, marine mammals, Anthozoa and Chondrichthyes are highlighted. Climate risk, vulnerability and exposure hotspots are distributed along the Western Mediterranean, Alboran, Aegean, and Adriatic Seas. At each Mediterranean marine ecoregion, 21%–31% of their threatened species have high climate risk. All Mediterranean marine protected areas host threatened species with high risk to climate change, with 90% having a minimum of 4 up to 19 species of high climate risk, making the objective of a climate‐smart conservation strategy a crucial task for immediate planning and action. Our findings aspire to offer new insights for systematic, spatially strategic planning and prioritization of vulnerable marine life in the face of accelerating climate change. [ABSTRACT FROM AUTHOR]

Marine ecosystems are increasingly threatened by the cumulative effects of multiple human pressures. Cumulative effect assessments (CEAs) are needed to inform environmental policy and guide ecosystem-based management. Yet, CEAs are inherently complex and seldom linked to real-world management processes. Therefore we propose entrenching CEAs in a risk management process, comprising the steps of risk identification, risk analysis and risk evaluation. We provide guidance to operationalize a risk-based approach to CEAs by describing for each step guiding principles and desired outcomes, scientific challenges and practical solutions. We reviewed the treatment of uncertainty in CEAs and the contribution of different tools and data sources to the implementation of a risk based approach to CEAs. We show that a risk-based approach to CEAs decreases complexity, allows for the transparent treatment of uncertainty and streamlines the uptake of scientific outcomes into the science-policy interface. Hence, its adoption can help bridging the gap between science and decision-making in ecosystem-based management. [ABSTRACT FROM AUTHOR]

Aim Identifying processes that determine climatic niche dynamics is difficult, especially for wide-ranging species where niche conservatism might differ at different life stages. Evolutionary history shapes climatic niche, with populations of the same or phylogenetically close species occupying similar conditions. However, the geographical separation of populations also leads to niche evolution as an adaptive response to local conditions. Here, we use five sea turtle species (loggerhead, green, leatherback, hawksbill, olive ridley) to test whether short- (environmental adaptation) or long-term (phylogenetic separation) evolutionary events determined the level of niche conservatism among distinct groups of nesting populations (termed Regional Management Units; RMUs) distributed across different ocean basins. Location Global. Methods We estimated the climatic niche of 4,829 georeferenced nesting locations using air and sea surface parameters. We quantified niche overlap among RMUs of the same species at a global scale and examined how the geographical ranges of each RMU are correlated with niche similarity. We also investigated the extent of niche conservatism among RMUs of different species in the same ocean basin. Results We found limited within-species niche similarity of RMUs at a global scale, with geographical range having negligible impact (latitudinal overlap, range size asymmetries). We detected generally higher niche overlap between RMUs of different species located within the same ocean basin, where the geographical range had a stronger effect on niche similarity. Main conclusions We show that adaptation to local conditions potentially prevails over distant evolutionary events when considering the climatic niche of RMUs of the same species across different oceans. Because sea turtles, like other long-distance migratory animals, occupy distinct climatic niches, our findings support the importance of understanding this phenomenon for different life stages, populations and species to preserve unique adaptations to different environments that might enhance future viability under climate change, as well as help identify key conservation areas. [ABSTRACT FROM AUTHOR]

Variations in environmental parameters (e.g. temperature) that form part of global climate change have been associated with shifts in the timing of seasonal events for a broad range of organisms. Most studies evaluating such phenological shifts of individual taxa have focused on a limited number of locations, making it difficult to assess how such shifts vary regionally across a species range. Here, by using 1445 records of the date of first nesting for loggerhead sea turtles (Caretta caretta) at different breeding sites, on different continents and in different years across a broad latitudinal range (25 -- 39° ′N), we demonstrate that the gradient of the relationship between temperature and the date of first breeding is steeper at higher latitudes, i.e. the phenological responses to temperature appear strongest at the poleward range limit. These findings support the hypothesis that biological changes in response to climate change will be most acute at the poleward range limits and are in accordance with the predictions of MacArthur's hypothesis that poleward range limit for species range is environmentally limited. Our findings imply that the poleward populations of loggerheads are more sensitive to climate variations and thus they might display the impacts of climate change sooner and more prominently. [ABSTRACT FROM AUTHOR]

Understanding the patterns of species richness and their environmental drivers, remains a central theme in ecological research and especially in the continental scales where many conservation decisions are made. Here, we analyzed the patterns of species richness from amphibians, reptiles and mammals at the EU level. We used two different data sources for each taxon: expert-drawn species range maps, and presence/absence atlases. As environmental drivers, we considered climate and land cover. Land cover is increasingly the focus of research, but there still is no consensus on how to classify land cover to distinct habitat classes, so we analyzed the CORINE land cover data with three different levels of thematic resolution (resolution of classification scheme ˗ less to more detailed). We found that the two types of species richness data explored in this study yielded different richness maps. Although, we expected expert-drawn range based estimates of species richness to exceed those from atlas data (due to the assumption that species are present in all locations throughout their region), we found that in many cases the opposite is true (the extreme case is the reptiles where more than half of the atlas based estimates were greater than the expert-drawn range based estimates). Also, we detected contrasting information on the richness drivers of biodiversity patterns depending on the dataset used. For atlas based richness estimates, landscape attributes played more important role than climate while for expert-drawn range based richness estimates climatic variables were more important (for the ectothermic amphibians and reptiles). Finally we found that the thematic resolution of the land cover classification scheme, also played a role in quantifying the effect of land cover diversity, with more detailed thematic resolution increasing the relative contribution of landscape attributes in predicting species richness. [ABSTRACT FROM AUTHOR]

Given the accelerating rate of biodiversity loss, the need to prioritize marine areas for protection represents a major conservation challenge. The three‐dimensionality of marine life and ecosystems is an inherent element of complexity for setting spatial conservation plans. Yet, the confidence of any recommendation largely depends on shifting climate, which triggers a global redistribution of biodiversity, suggesting the inclusion of time as a fourth dimension. Here, we developed a depth‐specific prioritization analysis to inform the design of protected areas, further including metrics of climate‐driven changes in the ocean. Climate change was captured in this analysis by considering the projected future distribution of >2000 benthic and pelagic species inhabiting the Mediterranean Sea, combined with climatic stability and heterogeneity metrics of the seascape. We identified important areas based on both biological and climatic criteria, where conservation focus should be given in priority when designing a three‐dimensional, climate‐smart protected area network. We detected spatially concise, conservation priority areas, distributed around the basin, that protected marine areas almost equally across all depth zones. Our approach highlights the importance of deep sea zones as priority areas to meet conservation targets for future marine biodiversity, while suggesting that spatial prioritization schemes, that focus on a static two‐dimensional distribution of biodiversity data, might fail to englobe both the vertical properties of species distributions and the fine and larger‐scale impacts associated with climate change. [ABSTRACT FROM AUTHOR]

Environmental policy integration is an acknowledged principle of sustainable development. Spatial planning may be a useful means of integrating two policies with differing objectives. The Birds and Habitats Directives of the European Union (EU) aim at preserving biodiversity through the conservation of the Natura 2000 protected areas network, while the EU's Environmental Noise Directive aims at improving human health and wellbeing by controlling environmental noise, through the preservation of Quiet Areas (QAs). Using Greece as an example, an integrated network of Natura 2000 sites and QAs permitted the identification of potential spatial overlaps. The established Natura 2000 network incorporates more than 30% of the QAs located in the open countryside of Greece, and the combined network includes 17 out of the 19 conservation priority habitat types. Flagship species (like bear, wolf and wild goat) show a preference for sites containing QAs. It may be possible to combine these two EU policies efficiently, as protected and quiet areas appear to be mutually beneficial. [ABSTRACT FROM PUBLISHER]

In many ecological communities, extinctions following habitat loss do not happen immediately. Understanding this delay is a major challenge, with conservation implications. In this issue, Otsu et al. show how landscape and management features affect the time lag. With this research as a starting point, we highlight the gaps and challenges still remaining in the study of extinction debt, especially in plant communities. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we evaluate the effectiveness of different well-tested conservation techniques in an effort to successfully protect sea turtle nests. From an eight-year study on the island of Zakynthos, West Greece, we have experimentally investigated the effectiveness of two different conservation techniques applied to loggerhead sea turtle nests and provided statistical measures to evaluate their conservation value. The categories of nests evaluated include: (i) nests incubated in situ, (ii) translocated into a beach hatchery, or (iii) protected by metal cages. Results of the analysis showed significant interannual variations in hatching success as obtained for each one of the three groups of nests. Significant differences were also observed when comparing hatching success data among the three groups of nests during the eight-year period. Overall, our results indicate that relocation of nests laid at highly threatened locations and the placement of protective cages on nests in situ provide adequate conservation measures that could allow an increase in hatchling production; although their choice and application should be based on the specific conditions and threats of each nest. [Copyright &y& Elsevier]

The magnitude and frequency of extreme warming events over the last decades pose threats to biodiversity. In the near future, heatwaves will become even more frequent and longer-lasting. As ectothermic species, sea turtles are particularly vulnerable to climate change, with their reproductive success and offspring sex ratios dependent on in-nest conditions, particularly temperature. Here, we used field observations and climate model outputs (1) to examine impacts of extreme conditions on reproductive output and (2) to project thermal conditions within nest environments through the year 2100. Data were collected from 225 green turtle nests over 5 years (2009–2013) at Akyatan beach, Turkey, one of the most important nesting sites for this species in the Mediterranean. Our results suggest that green turtle eggs may demonstrate some resilience to rising temperatures if periods of temperature extremes are short. Declines in hatching success were observed only after conditions exceed the 33 °C thermal threshold for two-fifths of the incubation period. Under a moderate climate scenario (RCP 4.5), the number of days above lethal thresholds (i.e., 35 °C) would increase from 1% at the year that the study was conducted to 19.3% in 2100. Although sea turtles have survived through past climate changes, these projections raise concerns about future recruitment success and the persistence of sea turtle populations. Regular monitoring and determination of tipping points at local scales are required to inform conservation and management under global warming. [ABSTRACT FROM AUTHOR]

Climate change (CC) is a key, global driver of change of marine ecosystems. At local and regional scales, other local human stressors (LS) can interact with CC and modify its effects on marine ecosystems. Understanding the response of the marine environment to the combined effects of CC and LS is crucial to inform marine ecosystem-based management and planning, yet our knowledge of the potential effects of such interactions is fragmented. At a global scale, we explored how cumulative effect assessments (CEAs) have addressed CC in the marine realm and discuss progress and shortcomings of current approaches. For this we conducted a systematic review on how CEAs investigated at different levels of biological organization ecological responses, functional aspects, and the combined effect of CC and HS. Globally, the effects of 52 LS and of 27 CC-related stressors on the marine environment have been studied in combination, such as industrial fisheries with change in temperature, or sea level rise with artisanal fisheries, marine litter, change in sediment load and introduced alien species. CC generally intensified the effects of LS at species level. At trophic groups and ecosystem levels, the effects of CC either intensified or mitigated the effects of other HS depending on the trophic groups or the environmental conditions involved, thus suggesting that the combined effects of CC and LS are context-dependent and vary among and within ecosystems. Our results highlight that large-scale assessments on the spatial interaction and combined effects of CC and LS remain limited. More importantly, our results strengthen the urgent need of CEAs to capture local-scale effects of stressors that can exacerbate climate-induced changes. Ultimately, this will allow identifying management measures that aid counteracting CC effects at relevant scales. Unlabelled Image • Local human stressors (LS) and climate change (CC) interact in marine environment. • We review how cumulative effect assessments (CEA) address CC & LS combined effects. • 52 LS & 27 CC stressors explored at different levels of biological diversity. • CC-LS combined effects are context-dependent and vary among and within ecosystems. • Urgency for CEAs to capture LS local effects that can exacerbate CC, to mitigate it. [ABSTRACT FROM AUTHOR]

Climate change is postulated to alter the distribution and abundance of species which serve as vectors for pathogens and is thus expected to affect the transmission of infectious, vector-borne diseases such as malaria. The ability to project and therefore, to mitigate the risk of potential expansion of infectious diseases requires an understanding of how vectors respond to environmental change. Here, we used an extensive dataset on the distribution of the mosquito Anopheles sacharovi, a vector of malaria parasites in Greece, southeast Europe, to build a modeling framework that allowed us to project the potential species range within the next decades. In order to account for model uncertainty, we employed a multi-model approach, combining an ensemble of diverse correlative niche models and a mechanistic model to project the potential expansion of species distribution and to delineate hotspots of potential malaria risk areas. The performance of the models was evaluated using official records on autochthonous malaria incidents. Our projections demonstrated a gradual increase in the potential range of the vector distribution and thus, in the malaria receptive areas over time. Linking the model outputs with human population inhabiting the study region, we found that population at risk increases, relative to the baseline period. The methodological framework proposed and applied here, offers a solid basis for a climate change impact assessment on malaria risk, facilitating informed decision making at national and regional scales. [ABSTRACT FROM AUTHOR]

Increased temperatures caused by anthropogenic climate change are becoming a major challenge for species. In particular, species that migrate over long distances are affected by altered climatic conditions at the various sites they frequent and en route. Here, we investigated whether climatic conditions experienced by sea turtles during their migration would change in the future. We focused on the post-nesting migrations of female loggerhead sea turtles (Caretta caretta) in the Mediterranean region, to explore climatic variability along four main migration corridors and their surrounding environment. We also modeled the impact of earlier onset of migration, as a potential adaptive behavioral response of Mediterranean loggerheads. We found that over the next 80 years, sea turtles will be exposed to significant increases in sea surface temperatures (SSTs) along their key migration corridors and the surrounding area (mean rate of 0.24 °C increase per decade). The projected increase in SST falls outside the range of SSTs currently reported within the examined corridors, but falls below the threshold defined as the upper thermal limit for this species. A highly variable climatic mosaic was identified within the distinct segments of the corridors. We found no evidence to support that phenological shifts might result in turtles being exposed to climatic conditions that are similar to current levels, in the future. Our outputs offer the first comprehensive spatial assessment of climatic patterns along extended areas used for the migration of sea turtles and highlight the need to quantify the relationship between altered conditions and species physiological and energetic status. This regional analysis could provide a background methodological framework for mapping and assessing spatiotemporal patterns of climatic variability along migratory areas of marine megafauna. • We developed an approach to examine climatic conditions for migrating loggerheads. • We investigated species exposure and adaptive capacity to climate change. • Mediterranean loggerheads might confront increasing temperatures during migration. • The efficiency of phenology, as adaptive mechanism for migration, is questionable. [ABSTRACT FROM AUTHOR]

Why females would mate with multiple partners and have multiple fathers for clutches or litters is a long-standing enigma. There is a broad dichotomy in hypotheses ranging from polyandry having benefits to simply being an unavoidable consequence of a high incidence of male-female encounters. If females simply give in to mating when it is too costly to avoid being harassed by males (convenience polyandry), then there should be a higher rate of mating as density increases. However, if females actively seek males because they benefit from multiple mating, then mating frequency, and consequently the incidence of multiple paternity of clutches, should be high throughout. To explore these competing explanations, here we review the incidence of multiple paternity for sea turtles nesting around the World. Across 30 rookeries, including all 7 species of sea turtle, the incidence of multiple paternity was only weakly linked to rookery size (r² = 0.14). However, using high resolution at-sea GPS tracking we show that the specifics of movement patterns play a key role in driving packing density and hence the likely rate of male-female encounters. When individuals use the same focal areas, packing density could be 100 × greater than when assuming individuals move independently. Once the extent of adult movements in the breeding season was considered so that movements and abundance could be combined to produce a measure of density, then across rookeries we found a very tight relationship (r² = 0.96) between packing density and the incidence of multiple paternity. These findings suggest that multiple paternity in sea turtles may have no benefit, but is simply a consequence of the incidence of male-female encounters. [ABSTRACT FROM AUTHOR]

• Sea currents could facilitate species migration by reducing movement energetic cost. • We projected optimal migration routes for loggerhead sea turtles. • Real migration tracks had higher energetic cost than projected ones. • Loggerhead sea turtles do not adjust their migration routes according to currents. • Climate changes on sea currents are not expected to alter migration routes. For marine species, traveling with the current potentially reduces energetic costs. Still, the extent to which organisms adjust routes to follow current flow remains an open question. Moreover, the extent to which climate change is altering sea currents, and in turn species migration routes, remains unknown, representing a major challenge to spatial ecology and conservation efforts. We developed an approach to assess the extent to which projected optimal paths and corridors overlap with the observed migration routes of loggerhead sea turtles (Caretta caretta), minimizing exposure to opposing sea currents. To illustrate this approach, we used migratory tracks of the species traveling between breeding and foraging areas in the Mediterranean Sea. We calculated the energetic costs to sea turtles based on actual tracks and corresponding optimal paths. We also explored whether projected changes in ocean currents, driven by climate change, would alter the spatial patterns of optimal routes. The energetic cost of observed tracks was, on average, 1.25 times higher than that of corresponding optimal paths. While optimal corridors differed spatially to observed corridors used by loggerheads, some positive correlations still existed for three cases (r s = 0.43, 0.42, 0.30). Climate change projections showed no significant change to the migratory movement of sea turtles, as corridors for different climatic conditions overlapped by at least 70%. Our results show that loggerheads do not explicitly take advantage of ocean currents to facilitate long distance migrations and reduce energetic demands. The contemporary and future migration routes are characterized by similar energetic demands and together with their strong spatial overlap suggest that climate change is expected to minimally alter the species migration routes in the future. The approach presented here could be applied to different spatial scales and marine taxa, allowing possible mechanisms between sea currents (or other environmental characteristics) and species movements to be elucidated. [ABSTRACT FROM AUTHOR]

Often climatic niche models predict that any change in climatic conditions will impact species abundance or distribution. However, the accuracy of models that just incorporate climatic information to predict future species habitat use is widely debated. Alternatively, environmental conditions may simply need to be above some minimum threshold of climatic suitability, at which point, other factors drive population size. Using the example of nesting sites of loggerhead sea turtles ( Caretta caretta ) in the Mediterranean (n = 105), we developed climatic niche models to examine whether a climatic suitability threshold could be identified as a climatic indicator in order for large populations of a widespread species to exist. We then assessed the climatic suitability of sites above and below this threshold in the past (∼1900) and future (∼2100). Most large sites that are currently above the climatic threshold were above the threshold in the past and future, particularly when future nesting seasonality shifted to start 1–2 months earlier. Our analyses highlight the importance of future phenological shifts for maintaining suitability. Our results provide a positive outlook for sea turtle conservation, suggesting that climatic conditions may remain suitable in the future at sites that currently support large nesting populations. Our study also provides an alternative way of interpreting the outputs of climatic niche models, by generating a threshold as an index of a minimum climatic suitability required to sustain large populations. This type of approach offers the possibility to benefit from information provided by climate-driven models, while reducing their inherent uncertainties. [ABSTRACT FROM AUTHOR]

Recent anthropogenic climate change is strongly associated with average shifts toward earlier seasonal timing of activity (phenology) in temperate-zone species. Shifts in phenology have the potential to alter ecological interactions, to the detriment of one or more interacting species. Recent models predict that detrimental phenological mismatch may increasingly occur between plants and their pollinators. One way to test this prediction is to examine data from ecological communities that experience large annual weather fluctuations. Taking this approach, we analyzed interactions over a four-year period among 132 plant species and 665 pollinating insect species within a Mediterranean community. For each plant species we recorded onset and duration of flowering and number of pollinator species. Flowering onset varied among years, and a year of earlier flowering of a species tended to be a year of fewer species pollinating its flowers. This relationship was attributable principally to early-flowering species, suggesting that shifts toward earlier phenology driven by climate change may reduce pollination services due to phenological mismatch. Earlier flowering onset of a species also was associated with prolonged flowering duration, but it is not certain that this will counterbalance any negative effects of lower pollinator species richness on plant reproductive success. Among plants with different life histories, annuals were more severely affected by flowering-pollinator mismatches than perennials. Specialized plant species (those attracting a smaller number of pollinator species) did not experience disproportionate interannual fluctuations in phenology. Thus they do not appear to be faced with disproportionate fluctuations in pollinator species richness, contrary to the expectation that specialists are at greatest risk of losing mutualistic interactions because of climate change. [ABSTRACT FROM AUTHOR]