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Climate change models for lizards assume that changes in its climate envelope (the climatic conditions that define a species’ distribution at a given time) are due to species being unable to withstand temperature increases, but this assumption has not been tested to assess its robustness. Studies on lizards’ preferred temperature in thermal gradients can fill this gap. Our aim is to assess the response to climate change of Liolaemus nigroviridis, a sky island lizard, by (i) assessing its thermal preference in a thermal gradient; and (ii) estimating which localities inhabited by the species would exhibit hours of activity restriction (Hr) implying an increased risk of local extinction. The results of this research and the information obtained from the literature concur on the consequences that climate change will have on the thermal ecology of Liolaemus from specialized habitats; the increase in substrate temperature is indeed a factor determining its presence. We also have information that not all populations of L. nigroviridis will be influenced in the same way; the northern populations will be more affected in terms of thermal restrictions and, in addition, Hr will increase at higher elevations. We propose that this be considered for future management for this species. [ABSTRACT FROM AUTHOR]

Climate warming is predicted to increase mean temperatures and thermal extremes on a global scale. Because their body temperature depends on the environmental temperature, ectotherms bear the full brunt of climate warming. Predicting the impact of climate warming on ectotherm diversity and distributions requires a framework that can translate temperature effects on ectotherm life‐history traits into population‐ and community‐level outcomes. Here we present a mechanistic theoretical framework that can predict the fundamental thermal niche and climate envelope of ectotherm species based on how temperature affects the underlying life‐history traits. The advantage of this framework is twofold. First, it can translate temperature effects on the phenotypic traits of individual organisms to population‐level patterns observed in nature. Second, it can predict thermal niches and climate envelopes based solely on trait response data and, hence, completely independently of any population‐level information. We find that the temperature at which the intrinsic growth rate is maximized exceeds the temperature at which abundance is maximized under density‐dependent growth. As a result, the temperature at which a species will increase the fastest when rare is lower than the temperature at which it will recover from a perturbation the fastest when abundant. We test model predictions using data from a naturalized–invasive interaction to identify the temperatures at which the invasive can most easily invade the naturalized's habitat and the naturalized is most likely to resist the invasive. The framework is sufficiently mechanistic to yield reliable predictions for individual species and sufficiently broad to apply across a range of ectothermic taxa. This ability to predict the thermal niche before a species encounters a new thermal environment is essential to mitigating some of the major effects of climate change on ectotherm populations around the globe. [ABSTRACT FROM AUTHOR]

Context: The Patagonian huemul, an endangered Odocoilinedeer, has an estimated 350–500 individuals remaining in Argentina. Today's population size, representing a numerical reduction of >99% of original estimates, is fragmented into small groups along ~2000 km of Andean mountains. The species' numbers were heavily reduced by past overexploitation and they disappeared in areas of high anthropogenic activity, predominantly the fertile valley bottoms. Aims: This research delineates the current potential distribution of Patagonian huemul by using climatic indicators, topographic and vegetational proxies, and anthropogenic pressure, to determine the relevance of the climatic envelope on current distribution. Methods: Occurrence records (latitude and longitude) were compiled (n = 159) by consulting the literature. Twenty environmental variables were used (WorldClim database) and two other representative environmental variables (normalised difference vegetation index (NDVI) and enhanced vegetation index (EVI)) were added to test their predictive power. We added the human footprint index (HFP) as a variable to control for model bias. Using the maximum entropy algorithm (MaxEnt), we modelled the species' potential distribution. We designated the historical distribution as area M. Additionally, we calculated three areas of distribution: current, historical and potential. Finally, we calculated distributional retraction of the species and area lost per year. Key results: The model showed good predictive power (AUCTest = 0.764 ± 0.091). However, low values were obtained for AUCtrain and AUCprom for the different predictor scenarios. Although the model shows the interaction among several climatic, environmental, and topographic variables, the human footprint index (39.9%) was the variable that most influenced the current potential distribution of this species. Conclusion: Our model shows that most of Patagonia's surface is climatically suitable for huemul. This suggests that the causes of distributional retraction are not related to limitations imposed by the climate envelope, but rather concur with recent research showing impact owing to the species' behavioural response to anthropogenic activity. Implications: Current populations are small, fragmented, and confined to poor-quality sites. Although the species is currently found mainly within protected areas, management actions must be initiated that promote innovative strategies in unprotected areas, as well as high-value habitats, particularly as protected areas contain limited fertile lower-valley habitats. Different anthropogenic factors heavily reduced the number of the huemul, an endangered Patagonian deer. Our aim was deliminated potencial distribution of huemul by using climatic indicators, topographic, vegetational, and anthropogenic. Our model shows that most of argentine Patagonia is climatically suitable for huemul, suggesting that the causes of the distributional retraction are linked to factors derived from the combination of characteristics of the species' biology and the increased anthropic. Therefore, it is necessary to conduct management and protection actions for species. [ABSTRACT FROM AUTHOR]

In response to climate warming, subalpine treelines are expected to move up in elevation since treelines are generally controlled by growing season temperature. Where treeline is advancing, dispersal differences and early life stage environmental tolerances are likely to affect how species expand their ranges. Species with an establishment advantage will colonize newly available habitat first, potentially excluding species that have slower establishment rates. Using a network of plots across five mountain ranges, we described patterns of upslope elevational range shift for the two dominant Great Basin subalpine species, limber pine and Great Basin bristlecone pine. We found that the Great Basin treeline for these species is expanding upslope with a mean vertical elevation shift of 19.1 m since 1950, which is lower than what we might expect based on temperature increases alone. The largest advances were on limber pine-dominated granitic soils, on west aspects, and at lower latitudes. Bristlecone pine juveniles establishing above treeline share some environmental associations with bristlecone adults. Limber pine above-treeline juveniles, in contrast, are prevalent across environmental conditions and share few environmental associations with limber pine adults. Strikingly, limber pine is establishing above treeline throughout the region without regard to site characteristic such as soil type, slope, aspect, or soil texture. Although limber pine is often rare at treeline where it coexists with bristlecone pine, limber pine juveniles dominate above treeline even on calcareous soils that are core bristlecone pine habitat. Limber pine is successfully "leap-frogging" over bristlecone pine, probably because of its strong dispersal advantage and broader tolerances for establishment. This early-stage dominance indicates the potential for the species composition of treeline to change in response to climate change. More broadly, it shows how species differences in dispersal and establishment may result in future communities with very different specific composition.

Refugia will be important to the response of alpine vegetation to climate change. Potential refugia exist at multiple scales, including a range-wide mesoscale. The climates of alpine grasslands of 23 mountain ranges of southern and central Europe were evaluated to assess whether each range would support potential refugia in projected future climates. The mean temperature the warmest month and quarter with the precipitation of the warmest quarter, derived from gridded global climate data at ~ 1 km resolution, were examined range-wide and for areas identified as alpine grassland to identify limits within each range. The overlap of current grassland climate and future range-wide climates, the latter calculated using regional projections from three global models with three socioeconomic driving scenarios, were assessed as potential refugia. Among the nine projections, three had none of the current grassland climates in any of the 23 ranges by 2100, while two retained more than 20% in more than half of the ranges. Most of the potential mesoscale refugia were in the Alps. Micro-refugia and warmer and drier fundamental climatic niches for alpine grassland species could mitigate these bleak results, but otherwise they are extremely threatened. [ABSTRACT FROM AUTHOR]

The recent climate change scenarios show significant increases in temperature and extreme drought events in Southern and Eastern Europe by the end of the 21st century, which will have a serious impact on forest growth and adaptation, and important consequences for forest management. The system of provenance regions, according to the OECD Scheme and EU Directive, was thought to encourage the use of the local seed sources, under the concept 'local is the best'. However, climate is changing faster than some species or populations can adapt or migrate, which raises some uncertainties with respect to the future performance of local populations. In Romania, as in other countries, the delimitation of provenance regions is based on geographical, ecological and vegetation criteria. The aim of this study is to evaluate: (1) the climate change that has occurred at the level of the provenance regions; (2) which regions will be most vulnerable to climate change; (3) which forest types will be the most vulnerable in a certain region; and (4) changes in the climatic envelope of forest species. Several climatic parameters and an ecoclimatic indices have been calculated and analyzed at the level of provenance regions, subregions and ecological sectors (forest types) in Romania, during the period 1951–2020. The results highlight a general shift towards warmer and drier conditions in the last 30 years, the mean annual temperature increasing with 0.3–1.1 °C across the provenance subregions. The De Martonne aridity index for the vegetation season shows that 86% of the ecological sectors fell into the arid and semiarid categories, which indicates a very high degree of vulnerability for forest species. On the Lang rainfall index, forest steppe climatic conditions occurred in all pure or mixed pedunculate oak forests, thermophile oak species, meadow forests, poplar and willow, Turkey oak and Hungarian oak forests. The Ellenberg coefficient highlights that the warming process is more evident along the altitude and the degree of vulnerability increase at lower altitude or at the edge of species distribution. The climate envelopes of many forest species have already shifted to another ecosystem's climate. This paper presents the importance of re-delineation the provenance regions for the production and deployment of forest reproductive materials according to the climate change occurred in the last decades, as a fundamental tool for an adaptive forest management. [ABSTRACT FROM AUTHOR]

Given the prospects of climate change and its influence on the species' geographic range, it is important to clarify which climate indicators best explain current distributions, as tools for the conservation of threatened species. It is also important to know the percentage of protection of suitable habitats for these species. In this paper we identify the main climatic variables that explain the distribution patterns of 16 species of medium and largemammals in Patagonia through the MaxEnt model, using 19 bioclimatic variables from WorldClim, elevation, NDVI and EVI and a proxy for anthropic pressure (human footprint). We calculated the percentage of coverage of protected areas for each species and found that most of the ideal habitat is outside them, and that strictly protected areas (I and II) have more records of presence than managed resource areas (III to VI). Species with restricted distributions are the most vulnerable to extinction because they are less resilient to changes in the climatic envelope, especially outside protected areas. [ABSTRACT FROM AUTHOR]

Climate change is shifting forest tree species distributions across elevational and latitudinal gradients, and these changes are often pronounced at ecotones where species meet their climatic bounds and are replaced by other species. Using an extensive ecotone composed of lower‐montane white fir (Abies concolor var. lowiana) and upper‐montane red fir (Abies magnifica var. magnifica) in the central Sierra Nevada range of California, USA, we (1) examined how the demographics of the ecotone have responded to recent climate using a field observational study and a historical dataset, (2) quantified climate drivers across species life stages using contemporary demographic data, and (3) tested the potential impacts of future climate on species‐specific seedling survival and growth in a fully factorial growth chamber experiment that varied temperature, growing season length, and water availability. A re‐examination of the ecotone midpoint after 35 yr suggested a reduction in A. concolor sapling and tree densities and a rise in A. magnifica proportional dominance between surveys. Seedling abundances across the ecotone indicated that A. magnifica tends to dominate the regeneration layer and currently forms an important component of the seedling community at elevations below those where A. magnifica saplings or trees begin to co‐dominate stands. Observational and experimental assessments suggest that temperature and precipitation serve as important drivers, differentiating A. concolor vs. A. magnifica distributions, and are primary stressors at the seedling stage. Seedlings of both species were adversely affected by experimental climate treatments, although A. concolor exhibited greater survival and a more conservative growth strategy under extreme climatic stress than A. magnifica. Projections indicate that historical climate conditions will rise by an amount greater than the ecotone's current elevational extent by the end of the 21st century. Differential drivers of species abundances suggest that the projected climate will expand conditions that promote A. concolor abundance and impede A. magnifica abundance across the ecotone; however, disturbance activity and microclimatic conditions will also influence regeneration and overstory tree dynamics. Our study demonstrates the importance of quantifying species‐specific responses to climate and indicates that widespread regeneration failure may be one possible consequence in which species exhibit strong sensitivity to projected climate conditions. [ABSTRACT FROM AUTHOR]

The recent climate change scenarios show significant increases in temperature and extreme drought events in Southern and Eastern Europe by the end of the 21st century, which will have a serious impact on forest growth and adaptation, and important consequences for forest management. The system of provenance regions, according to the OECD Scheme and EU Directive, was thought to encourage the use of the local seed sources, under the concept ‘local is the best’. However, climate is changing faster than some species or populations can adapt or migrate, which raises some uncertainties with respect to the future performance of local populations. In Romania, as in other countries, the delimitation of provenance regions is based on geographical, ecological and vegetation criteria. The aim of this study is to evaluate: (1) the climate change that has occurred at the level of the provenance regions; (2) which regions will be most vulnerable to climate change; (3) which forest types will be the most vulnerable in a certain region; and (4) changes in the climatic envelope of forest species. Several climatic parameters and an ecoclimatic indices have been calculated and analyzed at the level of provenance regions, subregions and ecological sectors (forest types) in Romania, during the period 1951–2020. The results highlight a general shift towards warmer and drier conditions in the last 30 years, the mean annual temperature increasing with 0.3–1.1 °C across the provenance subregions. The De Martonne aridity index for the vegetation season shows that 86% of the ecological sectors fell into the arid and semiarid categories, which indicates a very high degree of vulnerability for forest species. On the Lang rainfall index, forest steppe climatic conditions occurred in all pure or mixed pedunculate oak forests, thermophile oak species, meadow forests, poplar and willow, Turkey oak and Hungarian oak forests. The Ellenberg coefficient highlights that the warming process is more evident along the altitude and the degree of vulnerability increase at lower altitude or at the edge of species distribution. The climate envelopes of many forest species have already shifted to another ecosystem’s climate. This paper presents the importance of re-delineation the provenance regions for the production and deployment of forest reproductive materials according to the climate change occurred in the last decades, as a fundamental tool for an adaptive forest management.

An increase in greenhouse gas emissions has led to a rise in average global air and ocean temperatures. Increased sea surface temperatures can cause changes in species’ distributions, particularly those species close to their thermal tolerance limits. We use a bioclimate envelope approach to assess potential shifts in the range of marine macroalgae harvested in North American waters: rockweed (Fucus vesiculosus Linnaeus, 1753), serrated wrack (Fucus serratus Linnaeus, 1753), knotted wrack (Ascophyllum nodosum (Linnaeus) Le Jolis, 1863), carrageen moss (Chondrus crispus Stackhouse, 1797), and three kelp species (Laminaria digitata (Hudson) J.V. Lamouroux, 1813; Saccharina latissima (Linnaeus) C.E. Lane, C. Mayes, Druehl et G.W. Saunders, 2006; and Saccharina longicruris (Bachelot de la Pylaie) Kuntze, 1891). We determined species’ thermal limits from the current sea surface temperatures associated with their geographical distributions. Future distributions were based on sea surface temperatures projected for the year ∼2100 by four atmosphere-ocean general circulation models and earth system models for regional concentration pathways (RCPs) 4.5 and 8.5. Future distributions based on RCP 8.5 indicate that the presence of all but rockweed (F. vesiculosus) is likely to be threatened by warming waters in the Gulf of St. Lawrence and along the Atlantic coast of Nova Scotia. Range retractions of macroalgae will have significant ecological and economic effects including impacts on commercial fisheries and harvest rates and losses of floral and faunal biodiversity and production, and should be considered in the designation of marine protected areas.

Abstract Land managers require information about the ongoing and potential effects of future climate to coordinate responses for ecosystems, species, and human communities at scales that are operationally meaningful. Our study focused on the vulnerability for all upland ecosystem types of Arizona and New Mexico in the southwestern United States. Local vulnerability across the two‐state area was represented by the level of departure for late 21st‐century climate from the characteristic pre‐1990 climate envelope of the ecosystem type at each given location, resulting in a probability surface of climate impacts for the two‐state area and an uncertainty assessment based on agreement in results among multiple global climate models. Though the results varied from one ecosystem type to the next, the majority of lands were forecast as high vulnerability and low uncertainty, reflecting significant agreement among climate model projections for the southwestern United States. We then tested our results in relation to ongoing ecological processes that have both regional and global change implications and discovered significant relationships with wildfire severity, upward tree species recruitment, and the encroachment of scrub into semidesert grassland. The testing helped determine the efficacy of the vulnerability surface, as a product of relatively high spatial and thematic resolution, in supporting local planning and management decisions. Most important, this study links climate and changes in vegetation by ecosystem processes that are already ongoing. The results affirm the value of climate model downscaling and show that this portable approach to correlative modeling has value in determining the location and magnitude of potential climate‐related impacts.

Aim: We present a novel strategy for species distribution models (SDMs) aimed at predicting the potential distributions of range‐expanding invasive non‐native species (INNS). The strategy combines two established perspectives on defining the background region for sampling "pseudo‐absences" that have hitherto only been applied separately. These are the accessible area, which accounts for dispersal constraints, and the area outside the environmental range of the species and therefore assumed to be unsuitable for the species. We tested an approach to combine these by fitting SDMs using background samples (pseudo‐absences) from both types of background. Location: Global. Taxon: Invasive non‐native plants: Humulus scandens, Lygodium japonicum, Lespedeza cuneata, Triadica sebifera, Cinnamomum camphora. Methods: Presence‐background (or presence‐only) SDMs were developed for the potential global distributions of five plant species native to Asia, invasive elsewhere and prioritised for risk assessment as emerging INNS in Europe. We compared models where the pseudo‐absences were selected from the accessible background, the unsuitable background (defined using biological knowledge of the species' key limiting factors) or from both types of background. Results: Combining the unsuitable and accessible backgrounds expanded the range of environments available for model fitting and caused biological knowledge about ecological unsuitability to influence the fitted species‐environment relationships. This improved the realism and accuracy of distribution projections globally and, generally, within the species' ranges. Main conclusions: Correlative SDMs remain valuable for INNS risk mapping and management, but are often criticised for a lack of biological underpinning. Our approach partly addresses this concern by using prior knowledge of species' requirements or tolerances to define the unsuitable background for modelling, while also accommodating dispersal constraints through considerations of accessibility. It can be implemented with current SDM software and results in more accurate and realistic distribution projections. As such, wider adoption has potential to improve SDMs that support INNS risk assessment. [ABSTRACT FROM AUTHOR]

Aims Comparisons of climate envelopes among species have shown that niche conservatism tends to break down over time. Here, we use the Asian tree genus Platycarya (Juglandaceae) as a case study to test this tendency at relatively short timescales in a single lineage. This, together with a reanalysis of the extant literature, should help evaluate prospects of using correlations between climate and species occurrence data to infer evolutionary processes. Methods We rely on species distribution models (SDMs) and multivariate analyses to compare current and past (Last Glacial Maximum ~21ka) climatic envelopes between the two extant Platycarya species (Platycarya strobilacea and Platycarya longipes) and between mainland and Taiwan populations of P. strobilacea, paying particular attention to autocorrelation issues. We also review interpretations provided in similar studies comparing climate envelopes between and within species, including in studies involving native and introduced populations of the same species. Important Findings We find intraspecific but not interspecific differentiation in climate envelopes of Platycarya, despite the prediction that niche differentiation should be stronger between older groups. Our review also suggests that differentiation in climate envelopes need not imply rapid evolutionary divergence. Whereas SDMs can be used to raise evolutionary hypotheses to be validated with other data, we conclude that it should not be used to directly infer short-term evolutionary processes. [ABSTRACT FROM AUTHOR]

An ecological biogeographical perspective provides an understanding of the factors that shape the geographical distribution of organisms, their biodiversity and ecological speciation. Focusing on members of the lichen genus Solenopsora , which are strongly linked to a Mediterranean-type climate, we aimed to depict their environmental niches in the Apennine Peninsula. This area represents their ecological optima, as well as the biogeographical centre of distribution. On the basis of occurrences of Solenopsora congeners, we identified the key ecological factors that shape their environmental niches. Applying an ensemble approach, which merges the results of Random Forest, GLM and MaxEnt algorithms, suitability maps were developed. These are mainly influenced by geological substratum, temperature and precipitation. Occurrence of Solenopsora taxa seems to be mainly governed by low variability in diurnal temperature and tolerance to dryness, with precipitation in the range of 0–20 mm in the driest month and a minimum temperature of >5 °C in the coldest month. The sensitivity to diurnal temperature, an important indicator for climate change, suggests that the taxa confined to Mediterranean bioclimatic types (i.e. Solenopsora grisea , S. marina , S. olivacea subsp. olbiensis and S. olivacea subsp. olivacea) might be good indicators of climatic stability. The geological substratum was a strong limiting factor and separated the taxa into three groups: those growing on calcareous, siliceous and ultramafic substrata. Limited co-occurrence of species confined to one of the three categories suggests that the level of niche differentiation is on a microhabitat level. Accounting for ecological requirements, the taxa differ in their tolerance to sub-optimal conditions. The ecological niches of a sister subspecies pair with different reproduction strategies, fertile S. olivacea subsp. olivacea and sorediate S. olivacea subsp. olbiensis , overlap strongly. However, habitat suitability for S. olivacea subsp. olbiensis is greater in areas with higher precipitation in the driest month, whereas S. olivacea subsp. olivacea is more restricted to warmer and drier areas. We also report new regional records for Italy and the first records of S. cesatii in Serbia and Ukraine, and of S. liparina in Serbia. [ABSTRACT FROM AUTHOR]

Summary: The spread of many invasive plants could be facilitated by their presence in urban areas that may act as dispersal centres and by climate warming. Cortaderia selloana, pampas grass, is native to South America and raises considerable concern worldwide as an introduction. We used Maxent niche modelling, based on occurrence records and on a set of simulated occurrence points with high probability of presence in urbanised areas in France, where the species was introduced and is still planted. We calibrated the model with current climate data coupled with several habitat variables and used it to predict range shifts of C. selloana under four climate change scenarios (RCP) for 2060. The results were consistent with the known ecology of the species and showed that the most important variables that explain the current distribution in the introduced area were mean annual minimum temperatures, sandy habitats, disturbed habitats and urbanised areas. While the species already occupies large areas along the western and Mediterranean coasts, the models predicted an expansion northward and inland to the east under future climates. The area of suitable habitats could increase by up to 69% under the RCP 8.5 climate scenario in 2060 and by 116% with the extra occurrences in urban/suburban areas. This latter scenario suggests that areas like public and private gardens or urban parks, where the species is currently cultivated, could contribute to increase the invasion risk under climate warming. The results provide predictions of potential environments for the species, which can be helpful for anticipating its spread. [ABSTRACT FROM AUTHOR]

Fall armyworm, Spodoptera frugiperda, is a crop pest native to the Americas, which has invaded and spread throughout sub-Saharan Africa within two years. Recent estimates of 20-50% maize yield loss in Africa suggest severe impact on livelihoods. Fall armyworm is still infilling its potential range in Africa and could spread to other continents. In order to understand fall armyworm's year-round, global, potential distribution, we used evidence of the effects of temperature and precipitation on fall armyworm life-history, combined with data on native and African distributions to construct Species Distribution Models (SDMs). We also investigated the strength of trade and transportation pathways that could carry fall armyworm beyond Africa. Up till now, fall armyworm has only invaded areas that have a climate similar to the native distribution, validating the use of climatic SDMs. The strongest climatic limits on fall armyworm's yearround distribution are the coldest annual temperature and the amount of rain in the wet season. Much of sub-Saharan Africa can host year-round fall armyworm populations, but the likelihoods of colonising North Africa and seasonal migrations into Europe are hard to predict. South and Southeast Asia and Australia have climate conditions that would permit fall armyworm to invade. Current trade and transportation routes reveal Australia, China, India, Indonesia, Malaysia, Philippines and Thailand face high threat of fall armyworm invasions originating from Africa. [ABSTRACT FROM AUTHOR]

Pest risk analysts frequently ask if the climate of a pest risk analysis area could be suitable for the establishment of an organism of concern. Species distribution models can help to answer this question, but constructing them is technically complex, time consuming, and uninformative for additional non-modelled species. A quicker more broadly applicable approach involves using environmental distance metrics, including climate matching algorithms such as the ‘match climates regional’ function of CLIMEX (CLIMEX-MCR), to generate indices of climatic similarity between different locations without reference to particular species. Several studies have shown that various environmental distance metrics can provide biologically meaningful results. However, the veracity of the CLIMEX-MCR algorithm remains unevaluated, despite its application in numerous published studies. We used CLIMEX-MCR and high resolution New Zealand climate data to measure climatic similarities between New Zealand and the rest of the world. We then tested the veracity of the climatic match estimates by evaluating if their predictions regarding the suitability of New Zealand’s climate for 43 non-native ant species corresponded with empirical observations of those species in New Zealand. Non-native ants that are, or were once, established outdoors in New Zealand had overseas distributions that were climatically well matched with New Zealand. In contrast, species that either are established only indoors in New Zealand, or were observed to temporarily nest outdoors then die in New Zealand, had overseas distributions that were poorly matched. Species that are frequently intercepted at New Zealand’s border, but are not established there, generally also had overseas distributions with low climatic similarities to New Zealand. We also measured climatic similarities between New Zealand’s 13 national parks and the rest of the world. The overseas distributions of the non-native ants showed poor climatic matches with New Zealand’s national parks, which was consistent with the absence of persistent outdoor non-native ant populations in those parks. Our results support the utility of CLIMEX-MCR algorithm for pest risk analysis. [ABSTRACT FROM AUTHOR]

Abstract There are more than 580 natural areas in Oregon and Washington managed by 20 federal, state, local, and private agencies and organizations. This natural areas network is unparalleled in its representation of the diverse ecosystems found in the Pacific Northwest, and could prove useful for monitoring long‐term ecological responses to climate change. Our objectives were to (1) evaluate potential effects of climate change on these natural areas and (2) develop strategies for selecting and prioritizing sites for long‐term monitoring. Bioclimatic and Random Forest modeling were used to identify subsets of natural areas to prioritize for long‐term monitoring efforts based on the current and projected (2020s, 2050s, 2080s) outputs from 13 future climate models. Projection consensus suggest some of the largest effects of climate change on natural areas may be the result of a substantial range increase in suitable climate for warmer‐adapted forest types coupled with a reduction in habitat for cooler‐adapted forest types. We identify four strategies that could be used for prioritizing sites and help manage and protect biodiversity in the Pacific Northwest, especially given uncertainty over climate change effects.

Novel climates - emerging conditions with no analog in the observational record - are an open problem in ecological modeling. Detecting extrapolation into novel conditions is a critical step in evaluating bioclimatic projections of how species and ecosystems will respond to climate change. However, biologically informed novelty detection methods remain elusive for many modeling algorithms. To assist with bioclimatic model design and evaluation, we present a first-approximation assessment of general novelty based on a simple and consistent characterization of climate. We build on the seminal global analysis of Williams et al. (2007 PNAS, 104, 5738) by assessing of end-of-21st-century novelty for North America at high spatial resolution and by refining their standardized Euclidean distance into an intuitive Mahalanobian metric called sigma dissimilarity. Like this previous study, we found extensive novelty in end-of-21st-century projections for the warm southern margin of the continent as well as the western Arctic. In addition, we detected localized novelty in lower topographic positions at all latitudes: By the end of the 21st century, novel climates are projected to emerge at low elevations in 80% and 99% of ecoregions in the RCP4.5 and RCP8.5 emissions scenarios, respectively. Novel climates are limited to 7% of the continent's area in RCP4.5, but are much more extensive in RCP8.5 (40% of area). These three risk factors for novel climates - regional susceptibility, topographic position, and the magnitude of projected climate change - represent a priori evaluation criteria for the credibility of bioclimatic projections. Our findings indicate that novel climates can emerge in any landscape. Interpreting climatic novelty in the context of nonlinear biological responses to climate is an important challenge for future research. [ABSTRACT FROM AUTHOR]

It is important for conservationists to be able to assess the risks that climate change poses to species, in order to inform decision making. Using standardised and repeatable methods, we present a national-scale assessment of the risks of range loss and opportunities for range expansion that climate change could pose for over 3000 plants and animals. Species were selected by their occurrence in England, the primary focus of the study, but climate change impacts were assessed across Great Britain, widening their geographical relevance. A basic risk assessment that compared projected future changes in potential range with recently observed changes classified 21% of species as being at high risk and 6% at medium risk of range loss under a B1 climate change scenario. A greater number of species were classified as having a medium (16%) or high (38%) opportunity to potentially expand their distribution. A more comprehensive assessment, incorporating additional ecological information, including potentially confounding and exacerbating factors (e.g. dispersal, habitat availability and other constraints), was applied to 402 species, of which 35% were at risk of range loss and 42% may expand their range extent. This study covers a temperate region with a significant proportion of species at their poleward range limit; the balance of risks and opportunities from climate change may be different elsewhere. The outcome of both risk assessments varied between taxonomic groups, with bryophytes and vascular plants containing the greatest proportion of species at risk from climate change. Upland habitats contained more species at risk than other habitats. Whilst the overall pattern was clear, confidence was generally low for individual assessments, with the exception of well-studied taxa such as birds. In response to climate change, nature conservation needs to plan for changing species distributions and an uncertain future. [ABSTRACT FROM AUTHOR]

Plant species with divaricate forms are particularly common in New Zealand, where approximately 10% of all endemic woody species can be categorised as divaricate. A number of potential selective pressures have been proposed in order to explain this unusual feature of New Zealand flora. It has been suggested that divaricate architecture is a defensive adaptation that limits damage caused by either moa browsing or by climatic stresses. Climate-based hypotheses have proposed that the growth form confers a selective advantage in variable environments that are windy, droughty or frost-prone. One specific mechanism proposed for a climatic explanation is that the divaricate form might shield inner foliage from photoinhibition on cold sites with high winter solar irradiance. By determining which climatic factors are most associated with the occurrence of divaricate plants, we aim to evaluate these hypothesised climate relationships. This study uses organism occurrence records and logistic regression to compare the climate relationships of 12 divaricate species with those of larger-leaved congeners. Of the seven climatic variables that were considered, July minimum temperature was the variable that most consistently differentiated between divaricate species and their broad-leaved congeners, the former growing on sites that were significantly colder on average during this month. In general, divaricate plants were associated with lower winter light intensity than their broad-leaved congeners; although moderation analysis showed that this relationship was reversed on the coldest sites, the small size of this effect gives little support to the hypothesis that the divaricate form is especially advantageous in environments conducive to photoinhibition. However, the strong association with cold winters adds to a body of evidence that the divaricate form is favoured in frosty environments. [ABSTRACT FROM PUBLISHER]

The implications of climate change for terrestrial and aquatic taxa are for their dispersal pole-wards and/ or to higher altitudes as they track their climate niches. Here, bioclimatic models are developed to predict how projected climate change scenarios for a northern temperate region (Great Britain) shift the climate spaces (i.e. areas of suitable thermal habitat) for 12 freshwater fishes of the Salmonidae, Percidae, Esocidae and Cyprinidae families. Climate envelope models developed in Biomod2 used the current species' distributions and their relationships with current climatic variables, and projected these onto the BCC-CSM1-1 and HadGEM2-AO climate change scenarios (low and high emissions, 2050 and 2070) in full and no dispersal scenarios. Substantial contractions in climate spaces were predicted for native salmonid fishes, with decreases of up to 78% for Atlantic salmon Salmo salar , with these largely unchanged between the dispersal scenarios. Conversely, for the majority of cyprinid fishes, expansions were predicted, including into northern regions where they are current not present biogeographically. Only under the no dispersal scenarios did their predicted distributions remain the same as their current distributions. For all non-salmonid species, the most important climate variables in the model predictions related to temperature; for salmonids, they were a combination of temperature and shifts in annual mean precipitation. As these predictions suggest that there is potential for considerable alterations to the climate spaces of freshwater fishes in Great Britain during this century then regulatory and mitigation conservation actions should be undertaken to minimise these. [ABSTRACT FROM AUTHOR]

There are more than 580 natural areas in Oregon and Washington managed by 20 federal, state, local, and private agencies and organizations. This natural areas network is unparalleled in its representation of the diverse ecosystems found in the Pacific Northwest, and could prove useful for monitoring long-term ecological responses to climate change. Our objectives were to (1) evaluate potential effects of climate change on these natural areas and (2) develop strategies for selecting and prioritizing sites for long-term monitoring. Bioclimatic and Random Forest modeling were used to identify subsets of natural areas to prioritize for long-term monitoring efforts based on the current and projected (2020s, 2050s, 2080s) outputs from 13 future climate models. Projection consensus suggest some of the largest effects of climate change on natural areas may be the result of a substantial range increase in suitable climate for warmer-adapted forest types coupled with a reduction in habitat for cooler-adapted forest types. We identify four strategies that could be used for prioritizing sites and help manage and protect biodiversity in the Pacific Northwest, especially given uncertainty over climate change effects. [ABSTRACT FROM AUTHOR]

Predictions of species responses to climate change often focus on distribution shifts, although responses can also include shifts in body sizes and population demographics. Here, shifts in the distributional ranges ('climate space'), body sizes (as maximum theoretical body sizes, L∞) and growth rates (as rate at which L∞ is reached, K) were predicted for five fishes of the Cyprinidae family in a temperate region over eight climate change projections. Great Britain was the model area, and the model species were Rutilus rutilus, Leuciscus leuciscus, Squalius cephalus, Gobio gobio and Abramis brama. Ensemble models predicted that the species' climate spaces would shift in all modelled projections, with the most drastic changes occurring under high emissions; all range centroids shifted in a north-westerly direction. Predicted climate space expanded for R. rutilus and A. brama, contracted for S. cephalus, and for L. leuciscus and G. gobio, expanded under low-emission scenarios but contracted under high emissions, suggesting the presence of some climate-distribution thresholds. For R. rutilus, A. brama, S. cephalus and G. gobio, shifts in their climate space were coupled with predicted shifts to significantly smaller maximum body sizes and/or faster growth rates, aligning strongly to aspects of temperature-body size theory. These predicted shifts in L∞ and K had considerable consequences for size-at-age per species, suggesting substantial alterations in population age structures and abundances. Thus, when predicting climate change outcomes for species, outputs that couple shifts in climate space with altered body sizes and growth rates provide considerable insights into the population and community consequences, especially for species that cannot easily track their thermal niches. [ABSTRACT FROM AUTHOR]

Inherent characteristics of island species make them particularly susceptible to anthropogenic changes and need to be assessed to implement appropriate conservation strategies. The impacts of climate change are increasingly being investigated along elevational gradients since they provide natural laboratories to study how species respond to climatic variation. Ferns are particularly sensitive to air humidity and temperature and are therefore potentially useful as bio-indicators. This study addresses the question of whether the distributions of fern species richness and abundance have climatic correlates along an elevational gradient on the tropical volcanic island of Tahiti (French Polynesia). Analyses were conducted on two datasets: island-wide richness was estimated using published data on species elevational ranges, and local richness and abundance were addressed through a transect survey. Correlations with water availability, temperature, area availability, and a randomly-generated species richness pattern were investigated. Results showed that both diversity and abundance varied in association with climate. Rainfall was collinear with diversity in the lower half of the elevational gradient (R = 0.97), while temperature was the most important climatic correlate for diversity in the upper half (R = 0.98). The number of terrestrial fern individuals and epiphytic fern cover were both correlated with temperature (R = 0.86 and 0.81, respectively). Our results imply that impacts of climate change on ferns on Tahiti might include change in diversity and abundance, and increased extinction risk due to low overlap between current and projected species distributions. Ferns represent important indicator organisms that can be used to study species distributional responses to climate change in island ecosystems. [ABSTRACT FROM AUTHOR]

Federal land management agencies and conservation organizations have begun incorporating climate change vulnerability assessments (CCVAs) as an important component in the management and conservation of landscapes. It is often a challenge to translate that knowledge into management plans and actions, even when research infers species risk. Predictive maps can improve current CCVAs and assist in quantifying and visualizing species climate change vulnerability across large areas. We assessed the climate change risk for Greater Sage-Grouse (Centrocercus urophasianus; sage-grouse) habitat at two spatial scales in Utah and Nevada. At the local scale, multiple species climate envelopes were evaluated with additional stressors (fire, conifer encroachment, invasive grass, and human impact) to create risk maps for mesic (Strawberry) and xeric (Sheeprock) sage-grouse landscapes in Utah. Both landscapes were predicted to be at risk, but Sheeprock was found to be at higher risk due to future climate change implications coupled with additional habitat-degrading stressors. By using models, we are able to integrate complex interactions, and visualize the distribution of risk across broad spatial scales, providing land managers and researchers a valuable tool for CCVA and action plans. [ABSTRACT FROM AUTHOR]

Many uncertainties emerge dealing with future climate conditions and their possible impacts on forests. In this paper we suggest a probabilistic approach extending existing ensemble species distribution modeling concepts by addressing important sources of uncertainty. We exemplify our approach using European beech as the target tree species and bioclimatic predictors derived from WorldClim data. Model parameter uncertainty is represented by 1000 parameter samples from a Bayesian generalized linear model. Climate change impact ( CCI ) is based on 63 different climate model outputs using four RCP-scenarios ( R epresentative C oncentration P athways) in addition to the parameter uncertainty. The proposed difference of the probability of occurrence p occ to a predefined threshold, allows for evaluation of parameter uncertainty as well as for the uncertainty of future climate and describes the changing niche position. Further, we suggest the probability that the probability of occurrence exceeds a predefined threshold ( p exc ) as a metric for the distance of a site to the niche edge. These metrics are unambiguously determinable, intuitive and evident. Stands at a central, a marginal and an intermediate niche position are taken to exemplify deduction and application of p occ and p exc . A regional exercise shows how a map of p exc may support forest management planning and decision making under severe uncertainty. A key advantage of our novel metrics is the reformulation of common species distribution model (SDM) outputs in terms of risk thereby accounting for two important sources of uncertainty. [ABSTRACT FROM AUTHOR]

Species distribution models (SDMs) are widely used in basic and applied ecology, making it important to understand sources and magnitudes of uncertainty in SDM performance and predictions. We analyzed SDM performance and partitioned variance among prediction maps for 15 rare vertebrate species in the southeastern USA using all possible combinations of seven potential sources of uncertainty in SDMs: algorithms, climate datasets, model domain, species presences, variable collinearity, CO 2 emissions scenarios, and general circulation models. The choice of modeling algorithm was the greatest source of uncertainty in SDM performance and prediction maps, with some additional variation in performance associated with the comprehensiveness of the species presences used for modeling. Other sources of uncertainty that have received attention in the SDM literature such as variable collinearity and model domain contributed little to differences in SDM performance or predictions in this study. Predictions from different algorithms tended to be more variable at northern range margins for species with more northern distributions, which may complicate conservation planning at the leading edge of species’ geographic ranges. The clear message emerging from this work is that researchers should use multiple algorithms for modeling rather than relying on predictions from a single algorithm, invest resources in compiling a comprehensive set of species presences, and explicitly evaluate uncertainty in SDM predictions at leading range margins. [ABSTRACT FROM AUTHOR]

Extrinsic environmental factors influence the distribution and population dynamics of many organisms, including insects that are of concern for human health and agriculture. This is particularly true for vector-borne infectious diseases like malaria, which is a major source of morbidity and mortality in humans. Understanding the mechanistic links between environment and population processes for these diseases is key to predicting the consequences of climate change on transmission and for developing effective interventions. An important measure of the intensity of disease transmission is the reproductive number R0. However, understanding the mechanisms linking R0 and temperature, an environmental factor driving disease risk, can be challenging because the data available for parameterization are often poor. To address this, we show how a Bayesian approach can help identify critical uncertainties in components of R0 and how this uncertainty is propagated into the estimate of R0. Most notably, we find that different parameters dominate the uncertainty at different temperature regimes: bite rate from 15°C to 25°C; fecundity across all temperatures, but especially ~25-32°C; mortality from 20°C to 30°C; parasite development rate at ~15-16°C and again at ~33-35°C. Focusing empirical studies on these parameters and corresponding temperature ranges would be the most efficient way to improve estimates of R0. While we focus on malaria, our methods apply to improving process-based models more generally, including epidemiological, physiological niche, and species distribution models. [ABSTRACT FROM AUTHOR]

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Most range shift predictions focus on the dispersal phase of the colonization process. Because moving populations experience increasingly dissimilar nonclimatic environmental conditions as they track climate warming, it is also critical to test how individuals originating from contrasting thermal environments can establish in nonlocal sites., We assess the intraspecific variation in growth responses to nonlocal soils by planting a widespread grass of deciduous forests ( Milium effusum) into an experimental common garden using combinations of seeds and soil sampled in 22 sites across its distributional range, and reflecting movement scenarios of up to 1600 km. Furthermore, to determine temperature and forest-structural effects, the plants and soils were experimentally warmed and shaded., We found significantly positive effects of the difference between the temperature of the sites of seed and soil collection on growth and seedling emergence rates. Migrant plants might thus encounter increasingly favourable soil conditions while tracking the isotherms towards currently 'colder' soils. These effects persisted under experimental warming. Rising temperatures and light availability generally enhanced plant performance., Our results suggest that abiotic and biotic soil characteristics can shape climate change-driven plant movements by affecting growth of nonlocal migrants, a mechanism which should be integrated into predictions of future range shifts. [ABSTRACT FROM AUTHOR]