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Poleward and uphill range shifts are a common—but variable—response to climate change. We lack understanding regarding this interspecific variation; for example, functional traits show weak or mixed ability to predict range shifts.Characteristics of species' ranges may enhance prediction of range shifts. However, the explanatory power of many range characteristics—especially within‐range abundance patterns—remains untested.Here, we introduce a hypothesis framework for predicting range‐limit population trends and range shifts from the internal structure of the geographic range, specifically range edge hardness, defined as abundance within range edges relative to the whole range. The inertia hypothesis predicts that high edge abundance facilitates expansions along the leading range edge but creates inertia (either more individuals must disperse or perish) at the trailing range edge such that the trailing edge recedes slowly. In contrast, the limitation hypothesis suggests that hard range edges are the signature of strong limits (e.g. biotic interactions) that force faster contraction of the trailing edge but block expansions at the leading edge of the range.Using a long‐term avian monitoring dataset from northern Minnesota, USA, we estimated population trends for 35 trailing‐edge species and 18 leading‐edge species and modelled their population trends as a function of range edge hardness derived from eBird data. We found limited evidence of associations between range edge hardness and range‐limit population trends. Trailing‐edge species with harder range edges were slightly more likely to be declining, demonstrating weak support for the limitation hypothesis. In contrast, leading‐edge species with harder range edges were slightly more likely to be increasing, demonstrating weak support for the inertia hypothesis.These opposing results for the leading and trailing range edges might suggest that different mechanisms underpin range expansions and contractions, respectively. As data and state‐of‐the‐art modelling efforts continue to proliferate, we will be ever better equipped to map abundance patterns within species' ranges, offering opportunities to anticipate range shifts through the lens of the geographic range. [ABSTRACT FROM AUTHOR]

Aim: Global species distribution maps tend to be limited to a reduced number of species or are too coarse to inform ecological research and conservation actions at local scales. We developed a workflow to generate species range and area of habitat (AOH) maps tailored to local contexts based on expert information, community science observations and an ecoregion approach. We also developed a workflow to increase transparency in range maps and map the areas of uncertainty at the species and community levels using community science data. Location: North‐Western South America. Methods: We combined expert knowledge, community science observations, a new map of ecoregions for Colombia and national maps of land cover to produce species range and AOH maps for 94% of the terrestrial resident birds of Colombia (1633 species). We used community science records to validate the range maps and produce a species‐specific layer of uncertainty by calculating the distance between pixels classified as habitat and species occurrence points. Results: Compared to previous efforts, the new maps have higher species coverage and produced better validation scores for more than 50% of the species analysed. In addition, the produced maps also show macroecological patterns that follow natural boundaries, significantly improving the arbitrary patterns observed in previous mapping efforts. Uncertainty maps illustrate the spatial resolution and the extent at which these maps can be used with the highest confidence and highlight poorly surveyed areas that require extensive sampling. Main Conclusions: Combining information from expert sources, field observations and broad macroecological patterns is key to improve AOH maps that are fitted to local applications. Our uncertainty analysis can also guide concerted national efforts to survey specific localities. Our workflow can be used in multiple regions, countries and for other taxa, and we expect that it will improve local estimates of biogeographical and species diversity patterns. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Taxon Methods Results Main Conclusions Forest pathogens, insect pests and parasitic plants are among the most important disturbance agents in forested ecosystems. Understanding where pests occur and where they might occur in the future will be important for understanding their impacts on host trees, and planning for future pest outbreaks.North America.Insect pests, pathogens and parasitic plants of forest trees.Here, we develop and implement a framework to predict the contemporary distributions of 26 pest species that accounts for climate, host abundance and, for non‐native species, their spread on the landscape.We show that pest distributions can be predicted primarily by climatic variables. The abundance of individual host trees had only minor explanatory power, but the summed total of host abundance frequently had greater importance—suggesting forest composition and the relative frequency of hosts and non‐hosts place strong limits on pest distributions. Non‐native pests were strongly impacted by the distance from their original discovery location in North America, which tended to interact with climate variables—suggesting most non‐native pests are not yet at equilibrium with their potential climatic ranges in North America.This work helps to clarify the generalised controls on pest distributions and provide a framework for predicting pest distributions in future climates. [ABSTRACT FROM AUTHOR]

Fine‐scale spatial climate variation fosters biodiversity and buffers it from climate change, but ecological studies are constrained by the limited accessibility of relevant fine‐scale climate data. In this paper we introduce a novel form of species distribution model that uses species occurrences to predict high‐resolution climate variation. This new category of 'bioclimate' data, representing micro‐scale climate as experienced by one or more species of interest, is a useful complement to microclimate data from existing approaches. The modeling method, called BISHOP for 'bioclimate inference from species' high‐resolution occurrence patterns,' uses data on species occurrences, coarse‐scale climate, and fine‐scale physiography (e.g. terrain, soil, vegetation) to triangulate fine‐scale bioclimate patterns. It works by pairing a climate‐downscaling function predicting a latent bioclimate variable, with a niche function predicting species occurrences from bioclimate. BISHOP infers how physiography affects bioclimate, estimates how these effects vary geographically, and produces high‐resolution (10 m) maps of bioclimate over large regions. It also predicts species distributions. After introducing this approach, we apply it in an empirical study focused on topography and trees. Using data on 216 North American tree species, we document the biogeographic patterns that enable BISHOP, estimate how four terrain variables (northness, eastness, windward exposure, and elevational position) each influence three climate variables, and use these results to produce downscaled maps of tree‐specific bioclimate. Model validation demonstrates that inferred bioclimate outperforms macroclimate in predicting distributions of separate species not used during inference, confirming its ecological relevance. Our results show that nearby bioclimates can differ by 5°C in temperature and twofold in moisture, with equator‐facing, east‐facing, windward‐facing, and locally elevated sites exhibiting hotter, drier bioclimates on average. But these effects vary greatly across climate zones, revealing that topographically similar landscapes can differ strongly in their bioclimate variation. These results have important implications for micrometeorology, biodiversity, and climate resilience. [ABSTRACT FROM AUTHOR]

ABSTRACT Motivation Main Types of Variables Contained Spatial Location and Grain Time Period and Grain Major Taxa and Level of Measurement Software Format Accurate estimates of species distributions are crucial for biogeography, spatial conservation, and for assessing the impacts of human activities on species. However, existing approaches to estimate species distributions have typically neglected the influence of land use intensity, potentially overlooking the negative impacts of high‐intensity land uses on biodiversity. Here, we build a dataset documenting the habitat suitability of European land systems for terrestrial vertebrate species, based on a novel land system map of Europe that factors in land use intensity. Our database offers refined and up‐to‐date information on terrestrial vertebrate distributions in Europe by explicitly considering land use intensity.We created a table defining the suitability of land use classes as habitats for each species. We then built Area of Habitat (AOH) maps for each species by filtering out unsuitable habitat from the latest available estimates of species ranges. AOH maps were then compared with occurrence records from the Global Biodiversity Information Facility (GBIF). Processed datasets and R scripts are publicly available online, facilitating the use of our approach to refine expert‐based distributions for other taxa, land system classifications and regions worldwide.The AOH maps cover the spatial extent of the European Union (EU) with the United Kingdom, Norway, Switzerland, and the Western Balkans. The AOH maps are at a 1 km2 resolution.The dataset uses information published during the last 10 years.Habitat suitability was documented for 1155 terrestrial vertebrate species known to occur in Europe: 279 mammals, 520 birds, 251 reptiles and 104 amphibians.We provide the habitat suitability table in a comma‐separated values (csv) format. The AOH maps are available as raster files. R scripts are publicly accessible on GitHub. [ABSTRACT FROM AUTHOR]

The 2023 Annual Symposium of the Fisheries Society of the British Isles hosted opportunities for researchers, scientists, and policy makers to reflect on the state of art of predicting fish distributions and consider the implications to the marine and aquatic environments of a changing climate. The outcome of one special interest group at the Symposium was a collection of questions, organized under five themes, which begin to capture the state of the field and identify priorities for research and management over the coming years. The five themes were Physiology, Mechanisms, Detect and Measure, Manage, and Wider Ecosystems. The questions, 25 of them, addressed concepts which remain poorly understood, are data deficient, and/or are likely to be impacted in measurable or profound ways by climate change. Moving from the first to the last theme, the questions expanded in the scope of their considerations, from specific processes within the individual to ecosystem‐wide impacts, but no one question is bigger than any other: each is important in detecting, understanding, and predicting fish distributions, and each will be impacted by an aspect of climate change. In this way, our questions, particularly those concerning unknown mechanisms and data deficiencies, aimed to offer a guide to other researchers, managers, and policy makers in the prioritization of future work as a changing climate is expected to have complex and disperse impacts on fish populations and distributions that will require a coordinated effort to address. [ABSTRACT FROM AUTHOR]

Our knowledge of biodiversity hinges on sufficient data, reliable methods, and realistic models. Without an accurate assessment of species distributions, we cannot effectively target and stem biodiversity loss. Species range maps are the foundation of such efforts, but countless studies have failed to account for the most basic assumptions of reliable species mapping practices, undermining the credibility of their results and potentially misleading and hindering conservation and management efforts. Here, we use examples from the recent literature and broader conservation community to highlight the substantial shortfalls in current practices and their consequences for both analyses and conservation management. We detail how different decisions on data filtering impact the outcomes of analysis and provide practical recommendations and steps for more reliable analysis, whilst understanding the limits of what available data will reliably allow and what methods are most appropriate. Whilst perfect analyses are not possible for many taxa given limited data, and biases, ensuring we use data within reasonable limits and understanding inherent assumptions is crucial to ensure appropriate use. By embracing and enacting such best practices, we can ensure both the accuracy and improved comparability of biodiversity analyses going forward, ultimately enhancing our ability to use data to facilitate our protection of the natural world. [ABSTRACT FROM AUTHOR]

Eighty years ago, George S. Myers classified inland fishes in three divisions (primary, secondary and peripheral) based on their salinity tolerance and eco‐evolutionary history. Although this classification has been followed by many fish studies, it has also received considerable criticism. Here, we aim to test for differences in salinity and thermal tolerance, species traits and distribution patterns among the three divisions using data for about 21,000 species. We found that primary fishes have much less salinity tolerance than secondary and peripheral species, with some secondary fishes displaying the highest tolerances (>100 ppt). We also provide, for the first time, evidence of significant phylogenetic signal of salinity tolerance, comparable in magnitude to conservative traits, and show that studied peripheral and secondary species have maintained or even developed salinity tolerance, in contrast to primary fishes. Although peripheral fishes are the most different, and despite the large variability observed within some families, primary and secondary species also show differences in morphology and life‐history traits. The distribution ranges and genetic diversity of primary and secondary fish divisions are similar and differ from peripheral species, suggesting that although there is evidence of oceanic dispersal of a few secondary fishes at evolutionary time scales, it is a rare contemporary phenomenon. Importantly, a few findings outlined in this study, namely, differences in salinity tolerance, rely on limited data. Thus, we urge for additional empirical research on the salinity tolerance of freshwater fish, which remains largely unexplored, to help clarify differences among and within clades. [ABSTRACT FROM AUTHOR]

Aim: Global patterns in species distributions such as the latitudinal biodiversity gradient are of great interest to ecologists and have been thoroughly studied. Whether such a gradient holds true for the proportion of species associated with key ecotypes such as forests is however unknown. Identifying a gradient and ascertaining the factors causing it could further our understanding of community sensitivity to deforestation and uncover drivers of habitat specialization. The null hypothesis is that proportions of forest species remain globally consistent, though we hypothesize that proportions will change with differences in ecotype amount, spatial structure, and environmental stability. Here we study whether the proportion of forest species follows a latitudinal gradient, and test hypotheses for why this may occur. Location: Worldwide. Time period: Present. Major taxa studied: Terrestrial vertebrates. Methods: We combined range maps and habitat use data for all terrestrial vertebrates to calculate the proportion of forest species in an area. We then used data on the global distribution of current, recent historical, and long‐term historical forest cover, as well as maps of global disturbances and plant diversity to test our hypotheses using generalized linear models. Results: We identified a latitudinal gradient in the proportion of forest species whereby the highest proportions occurred at the equator and decreased polewards. We additionally found that the proportion of forest species increased with current forest cover, historical deforestation, plant structural complexity, and habitat stability. Despite the inclusion of these variables, the strong latitudinal gradient remained, suggesting additional causes of the gradient. Main conclusions: Our findings suggest that the global distribution of the proportion of forest species is a result of recent ecological, as well as long‐term evolutionary factors. Interestingly, high proportions of forest species were found in areas that experienced historical deforestation, suggesting a lagged response to such perturbations and potential extinction debt. [ABSTRACT FROM AUTHOR]

The geographic redistributions of species due to a rapidly changing climate are poised to perturb ecological communities and significantly impact ecosystems and human livelihoods. Effectively managing these biological impacts requires a thorough understanding of the patterns and processes of species geographic range shifts. While substantial recent redistributions have been identified and recognized to vary by taxon, region, and range geometry, there are large gaps and biases in the available evidence. Here, we use the largest compilation of geographic range change observations to date, comprised of 33,016 potential redistributions across 12,009 species, to formally assess within‐ and cross‐species coverage and biases and to motivate future data collection. We find that species coverage varies strongly by taxon and underrepresents species at high and low latitudes. Within species, assessments of potential redistributions came from parts of their geographic range that were highly uneven and non‐representative. For most species and taxa, studies were strongly biased toward the colder parts of species' distributions and thus significantly underrepresented populations that might get pushed beyond their maximum temperature limits. Coverage of potential leading and trailing geographic range edges under a changing climate was similarly uneven. Only 8% of studied species were assessed at both high and low latitude and elevation range edges, with most only covered at one edge. This suggests that substantial within‐species biases exacerbate the considerable geographic and taxonomic among‐species unevenness in evidence. Our results open the door for a more quantitative accounting for existing knowledge biases in climate change ecology and a more informed management and conservation. Our findings offer guidance for future data collection that better addresses information gaps and provides a more effective foundation for managing the biological impacts of climate change. [ABSTRACT FROM AUTHOR]

Reliable maps of species distributions are fundamental for biodiversity research and conservation. The International Union for Conservation of Nature (IUCN) range maps are widely recognized as authoritative representations of species' geographic limits, yet they might not always align with actual occurrence data. In recent area of habitat (AOH) maps, areas that are not habitat have been removed from IUCN ranges to reduce commission errors, but their concordance with actual species occurrence also remains untested. We tested concordance between occurrences recorded in camera trap surveys and predicted occurrences from the IUCN and AOH maps for 510 medium‐ to large‐bodied mammalian species in 80 camera trap sampling areas. Across all areas, cameras detected only 39% of species expected to occur based on IUCN ranges and AOH maps; 85% of the IUCN only mismatches occurred within 200 km of range edges. Only 4% of species occurrences were detected by cameras outside IUCN ranges. The probability of mismatches between cameras and the IUCN range was significantly higher for smaller‐bodied mammals and habitat specialists in the Neotropics and Indomalaya and in areas with shorter canopy forests. Our findings suggest that range and AOH maps rarely underrepresent areas where species occur, but they may more often overrepresent ranges by including areas where a species may be absent, particularly at range edges. We suggest that combining range maps with data from ground‐based biodiversity sensors, such as camera traps, provides a richer knowledge base for conservation mapping and planning. [ABSTRACT FROM AUTHOR]

Despite the medical importance of North African scorpions, many aspects of their ecology which may be important to understand envenoming patterns throughout their range, remain understudied. The region of Souss-Massa in central Morocco exhibits a high incidence of scorpion envenomings, with 29 437 cases reported between 2005 and 2010, resulting in 32 deaths. In the present study, we provide an updated inventory of scorpions occurring throughout the Souss-Massa region, with additional information about their distribution and notes on preferred habitats for each species observed. Sampling was carried out at 39 stations over a three-year period: June and August 2020, April and June 2022, and July and August 2023. Twelve species belonging to two families were recovered over the course of the study. The families Buthidae and Scorpionidae were represented by eleven and a single species respectively. Overall, this represents 71% of all species reported to occur in the Souss-Massa region. Apart from Androctonus mauritanicus, A. bourdoni, A. sergenti and Hottentotta gentili which are present in and around human dwellings, all other species were found in uninhabited areas. Apart from Scorpio mogadorensis, all the species of scorpions we recovered can cause severe envenomation with potentially fatal outcomes. Field-based ecological investigations should be encouraged to gain a more accurate and comprehensive understanding of scorpion distribution patterns and habitat preference. In turn, this will inform the health-science community of the etiological factors responsible for scorpion envenoming. [ABSTRACT FROM AUTHOR]

Changes in climate can alter environmental conditions faster than most species can adapt. A prediction under a warming climate is that species will shift their distributions poleward through time. While many studies focus on range shifts, latitudinal shifts in species' optima can occur without detectable changes in their range. We quantified shifts in latitudinal optima for 209 North American bird species over the last 55 y. The latitudinal optimum (m) for each species in each year was estimated using a bespoke flexible non-linear zero-inflated model of abundance vs. latitude, and the annual shift in m through time was quantified. One-third (70) of the bird species showed a significant shift in their optimum. Overall, mean peak abundances of North American birds have shifted northward, on average, at a rate of 1.5 km per year (±0.58 SE), corresponding to a total distance moved of 82.5 km (±31.9 SE) over the last 55 y. Stronger poleward shifts at the continental scale were linked to key species' traits, including thermal optimum, habitat specialization, and territoriality. Shifts in the western region were larger and less variable than in the eastern region, and they were linked to species' thermal optimum, habitat density preference, and habitat specialization. Individual species' latitudinal shifts were most strongly linked to their estimated thermal optimum, clearly indicating a climate-driven response. Displacement of species from their historically optimal realized niches can have dramatic ecological consequences. Effective conservation must consider within-range abundance shifts. Areas currently deemed "optimal" are unlikely to remain so. [ABSTRACT FROM AUTHOR]

Primates are declining worldwide and rapid infrastructure expansion, particularly roads, threatens their habitat. New roads fragment habitats allowing anthropogenic activities to occur in once pristine ecosystems; this is particularly impactful in tropical areas with high endemic biodiversity, as is occurring with primates in Colombia. However, temporal assessments of how roads impact local biodiversity are rare. We conducted a comprehensive assessment of the exposure of Colombian primates to roads from 1970 to 2015. Using a spatially explicit and species‐specific approach, we estimated the critical road density and the critical patch size primate species can withstand before going locally extinct. Then, overlapping 15 primate species (~40% of the primate species present in Colombia) ranges with Colombia's road networks over time, we determined the road expansion scope within each habitat and consequent fragmentation. Comparing the species critical road density and patch size, we determined the degree of road exposure of each species over time and its vulnerability to local extinction. Our results show that between 1970 and 2015, there were nearly 40 000 km2 where at least one species was at risk of local extinction, due to road expansion, principally in the Andean and Caribbean regions. Primates in these regions faced the greatest exposure to road impacts, with an average 16% increase in the amount of affected habitat during this period. Species in most need of conservation based on road exposure rankings are: Cebus versicolor, Aotus griseimembra, Ateles hybridus, Saguinus leucopus and Saguinus oedipus. Our study contributes to understanding road impacts on local biodiversity in one of the biodiversity hotspots across the tropics and highlights the need of infrastructure accounting for the necessary mitigation and conservation actions. [ABSTRACT FROM AUTHOR]

Biotic interactions are widely recognised as the backbone of ecological communities, but how best to study them is a subject of intense debate, especially at macro‐ecological scales. While some researchers claim that biotic interactions need to be observed directly, others use proxies and statistical approaches to infer them. Despite this ambiguity, studying and predicting the influence of biotic interactions on biogeographic patterns is a thriving area of research with crucial implications for conservation. Three distinct approaches are currently being explored. The first approach involves empirical observation and measurement of biotic interactions' effects on species demography in laboratory or field settings. While these findings contribute to theory and to understanding species' demographies, they can be challenging to generalise on a larger scale. The second approach centers on inferring biotic associations from observed co‐occurrences in space and time. The goal is to distinguish the environmental and biotic effects on species distributions. The third approach constructs extensive potential interaction networks, known as metanetworks, by leveraging existing knowledge about species ecology and interactions. This approach analyses local realisations of these networks using occurrence data and allows understanding large distributions of multi‐taxa assemblages. In this piece, we appraise these three approaches, highlighting their respective strengths and limitations. Instead of seeing them as conflicting, we advocate for their integration to enhance our understanding and expand applications in the emerging field of interaction biogeography. This integration shows promise for ecosystem understanding and management in the Anthropocene era. [ABSTRACT FROM AUTHOR]

The distribution and population density of the Critically Endangered Tarzan Chameleon (Calumma tarzan) in eastern humid forests of Madagascar was studied using line transect-distance sampling. Based on the results from species distribution models, eight sites were visited over a four-month period from February 2020 to March 2021. In total, 46 transects of 1 km were investigated in 23 different forest fragments to understand the distribution of C. tarzan. Another 28 transects of 200 m in length were surveyed to estimate population density. Among the 23 investigated forest fragments, C. tarzan was confirmed from 14 fragments belonging to five sites. All 14 records are completely new and represent a significant range extension for the species. Calumma tarzan is distributed within an elevation range of 604–1048 m above sea level. An analysis of the population of the species across sites show that density varies broadly and ranges from 25 to 78 individuals per hectare. This study fills important knowledge gap on a Critically Endangered and endemic chameleon species and is vital to the development of urgently needed conservation strategy for the Tarzan Chameleon. [ABSTRACT FROM AUTHOR]

Climate is assumed to strongly influence species distribution and abundance. Although the performance of many organisms is influenced by the climate in their immediate proximity, the climate data used to model their distributions often have a coarse spatial resolution. This is problematic because the local climate experienced by individuals might deviate substantially from the regional average. This problem is likely to be particularly important for sessile organisms like plants and in environments where small‐scale variation in climate is large. To quantify the effect of local temperature on vital rates and population growth rates, we used temperature values measured at the local scale (in situ logger measures) and integral projection models with demographic data from 37 populations of the forest herb Lathyrus vernus across a wide latitudinal gradient in Sweden. To assess how the spatial resolution of temperature data influences assessments of climate effects, we compared effects from models using local data with models using regionally aggregated temperature data at several spatial resolutions (≥1 km). Using local temperature data, we found that spring frost reduced the asymptotic population growth rate in the first of two annual transitions and influenced survival in both transitions. Only one of the four regional estimates showed a similar negative effect of spring frost on population growth rate. Our results for a perennial forest herb show that analyses using regionally aggregated data often fail to identify the effects of climate on population dynamics. This emphasizes the importance of using organism‐relevant estimates of climate when examining effects on individual performance and population dynamics, as well as when modeling species distributions. For sessile organisms that experience the environment over small spatial scales, this will require climate data at high spatial resolutions. [ABSTRACT FROM AUTHOR]

Background and Aims Climate change, including gradual changes and extreme weather events, is driving widespread species losses and range shifts. These climatic changes are felt acutely in intertidal ecosystems, where many organisms live close to their thermal limits and experience the extremes of both marine and terrestrial environments. A recent series of multiyear heatwaves in the northeast Pacific Ocean might have impacted species even towards their cooler, northern range edges. Among them, the high intertidal kelp Postelsia palmaeformis has traits that could make it particularly vulnerable to climate change, but it is critically understudied. Methods In 2021 and 2022, we replicated in situ and aerial P. palmaeformis surveys that were conducted originally in 2006 and 2007, in order to assess the state of northern populations following recent heatwaves. Changes in P. palmaeformis distribution, extent, density and morphometrics were assessed between these two time points over three spatial scales, ranging from 250 m grid cells across the entire 167 km study region, to within grid cells and the individual patch. Key Results We found evidence consistent with population stability at all three scales: P. palmaeformis remained present in all 250 m grid cells in the study region where it was previously found, and neither the extent within cells nor the patch density changed significantly between time points. However, there was evidence of slight distributional expansion, increased blade lengths and a shift to earlier reproductive timing. Conclusions We suggest that apparent long-term stability of P. palmaeformis might be attributable to thermal buffering near its northern range edge and from the wave-exposed coastlines it inhabits, which may have decreased the impacts of heatwaves. Our results highlight the importance of multiscale assessments when examining changes within species and populations, in addition to the importance of dispersal capability and local conditions in regulating the responses of species to climate change. [ABSTRACT FROM AUTHOR]

Biodiversity data records contain inaccuracies and biases. To overcome this limitation and establish robust geographic patterns, ecologists often curate records keeping those that are most suitable for their analyses. Yet, this choice is not straightforward and the outcome of the analysis may vary due to a trade‐off between data quality and volume. This problem is particularly recurrent for less‐studied groups with patchy sampling effort. The latitudinal pattern of mosses richness remains inconsistent across studies and these may emerge purely from sampling artefacts. Our main objective here is to assess the effect of different curation criteria on this spatial pattern in the Temperate Northern Hemisphere (above 20° latitude). We contrasted the geographical distribution of moss species records and the latitude‐species richness relation obtained under different data curation scenarios. These scenarios comprehend five sources of taxonomical standardisations and eight data cleaning filters. The analyses are based on the selection of well‐surveyed cells at 100 km cell resolution. The application of some 'data curation scenarios' severely affects the number of records selected for analysis and substantially changes the proportion of richness per cell. The sensitivity to data curation becomes detectable at regional and at the cell scales showing a large shift in the latitudinal richness peak in Europe, from 60° N to 45° N latitude, when only preserved specimens are selected and duplicates based on date of collection and coordinates are excluded. Our results stress the importance of justifying the criteria used for filtering biodiversity data retrieved from biodiversity databases to avoid detecting misleading patterns. Curating records under particular criteria compromises the information in some areas displaying different spatial information of mosses. This problem can be ameliorated if data filtering is combined with identifying well‐surveyed cells, render relatively constant results under different combinations of filtering even for less well‐known groups such as mosses. [ABSTRACT FROM AUTHOR]

I studied how a breeding forest bird community changed over 20 years in the largely undisturbed forests of the Northeast Uplands ecoregion of Connecticut to determine whether changes showed a relationship with the predicted effects of climate change as well as effects of habitat changes occurring over this period. Moreover, I wished to compare how changes documented at this regional scale compared with patterns observed at the continental scale and at a more local scale. I predicted that patterns detected would relate to the region's warming climate and maturing forests and that patterns would most closely resemble those of the continental scale. I gathered data via variable circular plot surveys performed at 5 different 3.20 km-long transects, which I surveyed for 2 years each at the beginning and end of the study period. Species richness and community density varied little over time. However, long-term turnover in species composition was nearly 30%, supporting the view that bird communities are dynamic rather than static assemblages. Community density more closely resembled continental patterns and species with population trends coincident with continental trends were 1.6 times greater than at the more local scale of the nearby Yale-Myers Forest. Species at their southern range limit undergoing population declines and species at their northern range limit undergoing population increases accounted for 26% of species, with 4 species showing the strongest population shifts having trends consistent with predicted effects of climate change. Forest interior species undergoing population increases and edge/successional species undergoing declines accounted for 36% of species. Moreover, increases were greater than decreases among forest interior populations. Furthermore, far more edge/successional species were declining than increasing. However, most populations undergoing changes were not associated with range limits. Moreover, 43% of species had population trends opposite to those predicted by a habitat hypothesis. The distributions and populations of community members may best be described as a consequence of a complex interplay of responses to multiple and sometimes conflicting factors and factors operating at differing environmental scales. Estudié cómo una comunidad de aves de bosque cambió en 20 años en bosques mayormente sin disturbios en la ecoregión de tierras altas de Connecticut para determinar si sus cambios estaban relacionados con los efectos predichos del cambio climático así como los efectos de cambio de hábitat que ocurrieron en ese periodo. Además, quise comparar cómo cambios documentados a escala regional se comparaban con patrones observados a escala continental y a una escala más local. Yo predije que los patrones detectados se relacionarían más con el calentamiento del clima y la maduración de los bosques de la región y que esos patrones detectados que parecerían más a los de la escala continental. Recolecté datos via censos de parcela circular variable realizados en cinco transeptos de 3,2 km de largo, que monitorée durante 2 años cada uno, al inicio y al final del periodo de estudio. La riqueza de especies y la densidad de comunidad varió poco en el tiempo. Sin embargo, el recambio a largo plazo en la composición de especies era de cerca de 30%, lo que apoya la idea de que las comunidades de aves son ensambles dinámicos en vez de estáticos. La densidad de comunidades que eran más similares a los patrones continentales y especies con tendencias poblacionales coincidían con tendencias continentales eran 1.6 veces mayores que a escala más local en el cercano bosque de Yale-Myers. Especies con cuyo límite sureño del rango de distribución sufren declives poblacionales y cuyo límite norteño tienen aumentos poblacionales representan un 26% de las especies, con 4 especies que muestran los cambios más fuertes poblacionales tendientes a lo predicho por los efectos del cambio climático. Las especies de interior de bosque con incrementos poblacionales y especies de borde/sucesión con declives representaron el 36% de las especies. Más aún, los incrementos fueron mayores que los declives en especies de interior de bosque. Además, había más especies de borde/sucesión que estaban declinando en vez de aumentando. Sin embargo, la mayoría de las especies que estaban cambiando no se asociaban a límites de rango. Más aún, el 43% de las especies tenían tendencias poblacionales opuestas a lo predicho por la hipótesis de hábitat. Las distribuciones poblaciones de miembros de las comunidades pueden ser mejor descritas como una consecuencia de interacciones complejas que responden a múltiples factores, a veces en conflicto y que operan a distintas escalas ambientales. Palabras clave: densidad de comunidad, distribución de especies, recambio de especies, riqueza de especies, tendencias de población. [ABSTRACT FROM AUTHOR]

Due to historical under‐sampling of the deep ocean, the distributional ranges of mesopelagic zooplankton are not well documented, leading to uncertainty about the mechanisms that shape midwater zooplankton community composition. Using a combination of DNA metabarcoding (18S‐V4 and mtCOI) and trait‐based analysis, we characterized zooplankton diversity and community composition in the upper 1000 m of the northeast Pacific Ocean. We tested whether the North Pacific Transition Zone is a biogeographic boundary region for mesopelagic zooplankton. We also tested whether zooplankton taxa occupying different vertical habitats and exhibiting different ecological traits differed in the ranges of temperature, Chl‐a, and dissolved oxygen conditions inhabited. The depth of the maximum taxonomic richness deepened with increasing latitude in the North Pacific. Community similarity in the mesopelagic zone also increased in comparison with the epipelagic zone, and no evidence was found for a biogeographic boundary between previously delineated mesopelagic biogeochemical provinces. Epipelagic zooplankton exhibited broader temperature and Chl‐a ranges than mesopelagic taxa. Within the epipelagic, taxa with broader temperature and Chl‐a ranges also had broader distributional ranges. However, mesopelagic taxa were distributed across wider dissolved oxygen ranges, and within the mesopelagic, only oxygen ranges covaried with distributional ranges. Environmental and distributional ranges also varied among traits, both for epipelagic taxa and mesopelagic taxa. The strongest differences in both environmental and distributional ranges were observed for taxa with or without diel vertical migration behavior. Our results suggest that species traits can influence the differential effects of physical dispersal and environmental selection in shaping biogeographic distributions. [ABSTRACT FROM AUTHOR]

Summary: Functional traits offer a promising avenue to improve predictions of species range shifts under climate change, which will entail warmer and often drier conditions. Although the conceptual foundation linking traits with plant performance and range shifts appears solid, the predictive ability of individual traits remains generally low. In this review, we address this apparent paradox, emphasizing examples of woody plants and traits associated with drought responses at the species' rear edge. Low predictive ability reflects the fact not only that range dynamics tend to be complex and multifactorial, as well as uncertainty in the identification of relevant traits and limited data availability, but also that trait effects are scale‐ and context‐dependent. The latter results from the complex interactions among traits (e.g. compensatory effects) and between them and the environment (e.g. exposure), which ultimately determine persistence and colonization capacity. To confront this complexity, a more balanced coverage of the main functional dimensions involved (stress tolerance, resource use, regeneration and dispersal) is needed, and modelling approaches must be developed that explicitly account for: trait coordination in a hierarchical context; trait variability in space and time and its relationship with exposure; and the effect of biotic interactions in an ecological community context. [ABSTRACT FROM AUTHOR]

Aims: Colonization by non‐native ants represents one of the gravest potential threats to island ecosystems. It is necessary to identify general mechanisms by which non‐native species are able to colonize and persist in order to inform future prevention and management. We studied a model‐island assemblage of 17 non‐native ant species with aim of identifying the spatial source of introductions and assessing how such a diversity of species are able to coexist. Location: Data were collected on Ascension Island: an ideal study system for its intermediate area, compact shape, spatial heterogeneity, lack of native ant species, and availability of non‐native ant records dating back to the 1800s. Methods: We collected over 47,000 individual ants from 73 sites using a range of baited traps and survey techniques. We combined this novel data with past occurrence records in order to determine whether human settlements have historically been the source of ant introductions and to quantify the mean rate at which species have dispersed across the island. Analysis of standardized field data revealed the extent to which ants were partitioning ecological niche space via (1) habitat separation, (2) fine‐scale resource partitioning and (3) climatic heterogeneity. Results: Ants were radiating at a linear rate of approximately 0.5 km2 per year from human settlements on this island, with the most widespread species having been introduced earliest. After accounting for incomplete colonization, we found no evidence to suggest habitat separation between species. Instead, we found significant niche separation through resource partitioning and weather‐dependent activity patterns. Main Conclusions: Our results indicate that non‐native ants can coexist in very close proximity and are therefore capable of existing at great diversity on even small islands. It is inevitable that ant colonization will continue without increased biosecurity measures, habitat restoration around settlements and conservation of native species populations. [ABSTRACT FROM AUTHOR]

Policy makers require high‐level summaries of biodiversity change. However, deriving such summaries from raw biodiversity data is a complex process involving several intermediary stages. In this paper, we describe an operational workflow for generating annual estimates of species occupancy at national scales from raw species occurrence data, which can be used to construct a range of policy‐relevant biodiversity indicators. We describe the workflow in detail: from data acquisition, data assessment and data manipulation, through modelling, model evaluation, application and dissemination. At each stage, we draw on our experience developing and applying the workflow for almost a decade to outline the challenges that analysts might face. These challenges span many areas of ecology, taxonomy, data science, computing and statistics. In our case, the principal output of the workflow is annual estimates of occupancy, with measures of uncertainty, for over 5000 species in each of several defined 'regions' (e.g. countries, protected areas, etc.) of the UK from 1970 to 2019. This data product corresponds closely to the notion of a species distribution Essential Biodiversity Variable (EBV). Throughout the paper, we highlight methodologies that might not be applicable outside of the UK and suggest alternatives. We also highlight areas where the workflow can be improved; in particular, methods are needed to mitigate and communicate the risk of bias arising from the lack of representativeness that is typical of biodiversity data. Finally, we revisit the 'ideal' and 'minimal' criteria for species distribution EBVs laid out in previous contributions and pose some outstanding questions that should be addressed as a matter of priority. Going forward, we hope that this paper acts as a template for research groups around the world seeking to develop similar data products. [ABSTRACT FROM AUTHOR]

Forecasting the future state of a species is a tricky process, as there are numerous hidden factors that influence species trajectories in addition to the obvious unknowns about the future state of the planet. We echo the guidance of Clare et al. (2024) to use near‐term and long‐term forecasting in complementary ways. Near‐term forecasts can be used to guide specific management and conservation actions, which can be updated as new data and evidence are collected. Long‐term forecasts can be used to characterize uncertainty further into the future, which can help guide longstanding conservation planning and legislative actions that are based on such uncertainty in possible future outcomes. [ABSTRACT FROM AUTHOR]

Closely related, ecologically similar species often segregate their distributions along environmental gradients of time, space, and resources, but previous research suggests diverse underlying causes. Here, we review reciprocal removal studies in nature that experimentally test the role of interactions among species in determining their turnover along environmental gradients. We find consistent evidence for asymmetric exclusion coupled with differences in environmental tolerance causing the segregation of species pairs, where a dominant species excludes a subordinate from benign regions of the gradient but is unable to tolerate challenging regions to which the subordinate species is adapted. Subordinate species were consistently smaller and performed better in regions of the gradient typically occupied by the dominant species compared with their native distribution. These results extend previous ideas contrasting competitive ability with adaptation to abiotic stress to include a broader diversity of species interactions (intraguild predation, reproductive interference) and environmental gradients, including gradients of biotic challenge. Collectively, these findings suggest that adaptation to environmental challenge compromises performance in antagonistic interactions with ecologically similar species. The consistency of this pattern across diverse organisms, environments, and biomes suggests generalizable processes structuring the segregation of ecologically similar species along disparate environmental gradients, a phenomenon that we propose should be named the competitive exclusion–tolerance rule. [ABSTRACT FROM AUTHOR]

Questions: Geographic gradients of beta‐diversity help understanding the relationship between species and their environment. However, on a global scale, such patterns are only known for a few taxa, mainly terrestrial vertebrates, especially when considering the phylogenetic dimension. Here, we present the first global analysis of phylogenetic beta‐diversity (PBD) for angiosperms. We aim to disentangle the relative contribution of PBD components (turnover‐ and nestedness‐resultant differences) and the deviation of PBD given the taxonomic beta‐diversity (TBD) along environmental and geographic gradients. Location: Global. Methods: We compiled range maps of 207,146 angiosperm species at 1° cells and calculated PBD for assemblages formed by each focal cell and its neighboring cells in radii of 1.5° and 2° ("moving‐window" approach). PBD was decomposed into turnover‐ and nestedness‐resultant components, evaluating their relative importance as the proportion of nestedness‐resultant PBD to the total PBD (PBDratio). To evaluate lineage exchanges, we calculated the deviation of PBD from TBD (PBDdev). We assessed the breakpoints of relationship between PBD and geographic (latitude and elevation) and environmental (temperature and precipitation) gradients using linear piecewise regressions. Results: The turnover‐resultant component was predominant in shaping the global angiosperm PBD pattern. PBDratio was positively correlated with temperature, having a breakpoint around 14°. Because PBDdev was mostly positive, TBD prevailed over PBD; PBDdev was correlated significantly with latitude and temperature gradients, being higher (i.e., low lineage replacement compared with species replacement) at latitudes above 50° N, and in colder climates (below 2°C). Conclusions: We provided the first global assessment of current geographic PBD patterns for angiosperms. Our results showed that such patterns are largely dictated by global environmental and geographic gradients, with lineage replacement being more important than lineage loss in virtually all areas, except at higher latitudes and on islands and peninsulas. [ABSTRACT FROM AUTHOR]

Background and Aims How well plants reproduce near their geographic range edge can determine whether distributions will shift in response to changing climate. Reproduction at the range edge can be limiting if pollinator scarcity leads to pollen limitation, or if abiotic stressors affect allocation to reproduction. For many animal-pollinated plants with expanding ranges, the mechanisms by which they have overcome these barriers are poorly understood. Methods In this study, we examined plant–pollinator interactions hypothesized to impact reproduction of the black mangrove, Avicennia germinans , which is expanding northward in coastal Florida, USA. We monitored insects visiting A. germinans populations varying in proximity to the geographic range edge, measured the pollen loads of the most common insect taxa and pollen receipt by A. germinans stigmas, and quantified flower and propagule production. Key Results We found that despite an 84 % decline in median floral visits by insects at northernmost versus southernmost sites, range-edge pollen receipt remained high. Notably, local floral visitor assemblages exhibited substantial turnover along the study's latitudinal gradient, with large-bodied bees and hover flies increasingly common at northern sites. We also observed elevated flower production in northern populations and higher per capita reproductive output at the range edge. Furthermore, mean propagule mass in northern populations was 18 % larger than that from the southernmost populations. Conclusions These findings reveal no erosion of fecundity in A. germinans populations at range limits, allowing rapid expansion of mangrove cover in the region. These results also illustrate that substantial turnover in the assemblage of flower-visiting insects can occur at an expanding range edge without altering pollen receipt. [ABSTRACT FROM AUTHOR]

Microclimate research gained renewed interest over the last decade and its importance for many ecological processes is increasingly being recognized. Consequently, the call for high‐resolution microclimatic temperature grids across broad spatial extents is becoming more pressing to improve ecological models. Here, we provide a new set of open‐access bioclimatic variables for microclimate temperatures of European forests at 25 × 25 m2 resolution. [ABSTRACT FROM AUTHOR]

Motivation: Aquatic insects comprise 64% of freshwater animal diversity and are widely used as bioindicators to assess water quality impairment and freshwater ecosystem health, as well as to test ecological hypotheses. Despite their importance, a comprehensive, global database of aquatic insect occurrences for mapping freshwater biodiversity in macroecological studies and applied freshwater research is missing. We aim to fill this gap and present the Global EPTO Database, which includes worldwide geo‐referenced aquatic insect occurrence records for four major taxa groups: Ephemeroptera, Plecoptera, Trichoptera and Odonata (EPTO). Main type of variables contained: A total of 8,368,467 occurrence records globally, of which 8,319,689 (99%) are publicly available. The records are attributed to the corresponding drainage basin and sub‐catchment based on the Hydrography90m dataset and are accompanied by the elevation value, the freshwater ecoregion and the protection status of their location. Spatial location and grain: The database covers the global extent, with 86% of the observation records having coordinates with at least four decimal digits (11.1 m precision at the equator) in the World Geodetic System 1984 (WGS84) coordinate reference system. Time period and grain: Sampling years span from 1951 to 2021. Ninety‐nine percent of the records have information on the year of the observation, 95% on the year and month, while 94% have a complete date. In the case of seven sub‐datasets, exact dates can be retrieved upon communication with the data contributors. Major taxa and level of measurement: Ephemeroptera, Plecoptera, Trichoptera and Odonata, standardized at the genus taxonomic level. We provide species names for 7,727,980 (93%) records without further taxonomic verification. Software format: The entire tab‐separated value (.csv) database can be downloaded and visualized at https://glowabio.org/project/epto%5fdatabase/. Fifty individual datasets are also available at https://fred.igb‐berlin.de, while six datasets have restricted access. For the latter, we share metadata and the contact details of the authors. [ABSTRACT FROM AUTHOR]

Documenting climate‐induced range shifts of freshwater fish is difficult because there are few spatially representative, long‐term data sets with re‐surveys of the same location over time. While such standardised data sets would allow for the identification of range shifts, most data sets are confounded by changing sampling priorities and methodologies through time. Finding a robust framework for detecting climate‐induced range shifts thus remains a research priority. Using a database from stream surveys conducted during the period 1957–2019, we employed a multi‐method framework for determining whether 10 stream fish species (nine warm‐water, one cold‐water) have exhibited elevational range shifts within the North Platte River watershed, Wyoming, USA. By employing a combination of different approaches (predictive reference models, quantile regressions, spatial aggregations), we produced a consensus framework for determining whether observed range expansions and range contractions were consistent across species. The weight of evidence from our consensus framework (>50% of all modelling approaches) indicated strong support for upstream range expansions of three (33%) warm‐water species, including a long‐established nonnative species (common carp [Cyprinus carpio]). The consensus framework revealed no evidence for range contractions of one cold‐water trout species (brown trout [Salmo trutta]). As global climate change continues, the value of historical datasets for evaluating pre‐warming, baseline conditions will increase. Given the methodological limitations of different analytical approaches, our findings illustrate that consensus frameworks based on the weight of evidence can improve confidence in the detection of climate‐induced range shifts when robust historical data sets are lacking. [ABSTRACT FROM AUTHOR]

South Africa is a megadiverse country. Here, natural communities are unevenly distributed across, and within, seven distinct biomes. In such heterogeneous landscapes, understanding spatial patterns of biodiversity is essential for planning and implementing efficient conservation measures.The southern Kalahari, forming part of South Africa's savanna biome, is an arid region of peculiarly high diversity and endemism. The responses of orthopteran assemblages to changing environmental conditions across the Kalahari were investigated by comparing alpha and beta diversity levels across discrete vegetation types in the Tswalu Kalahari Reserve. The degree of association between species and specific vegetation types were also studied and how a key life history trait ‐ dispersal ability – influences community composition was determined.This study identified 46 grasshopper species within the reserve, which compares well with richness levels in other more productive habitats of the country. Local (alpha) diversity was higher in mountain and mountain‐ecotone sites versus vegetation types on the plains, and species turnover was also exceptionally high – approaching 100% ‐ across these two groups. The few (3) dispersal limited species recovered were associated only with the mountain‐ecotone group, with emergent dominance patterns suggesting that competitive rather than dispersal abilities determine the species composition of unique assemblages in the landscape.Topology plays a key role in maintaining spatial diversity across the southern Kalahari landscape. Mountains, and their ecotones, promote not only species turnover, but also richness and functional diversity. These can be viewed as islands of diversity, and should be targeted priority areas for conservation beyond the boundaries of protected areas. [ABSTRACT FROM AUTHOR]

When species can access all parts of the landscape, species‐sorting metacommunity theory predicts that community composition depends on habitat choice and interactions with other species and the environment. These filtering processes can also depend on species' traits.The authors investigated how traits mediate a species‐sorting process in determining butterfly community composition in a naturally patchy landscape in the tropical Western Ghats, India. The authors asked, do traits mediate access to certain habitats and does seasonality affect these patterns? The authors surveyed 56 habitat patches in three habitat types: laterite plateau grasslands, ridge grassland, and moist‐deciduous forest, in a 65‐km2 landscape.Non‐palatable butterflies showed similar occurrences across seasons and habitats, but palatable butterflies were less commonly encountered in open habitats in the dry season. Polyphagous butterflies occurred infrequently in the dry season in laterite habitats, potentially indicating emigration or diapause patterns are linked to diet breadth.All species were present in all habitats, implying dispersal does not limit access to different habitat patches, consistent with the species‐sorting metacommunity concept. Nevertheless, butterfly occurrence was strongly influenced by the interaction of mobility and habitat type with sedentary species occurring less often in low‐resource open laterite patches than mobile species.Species sorting is typically regarded as occurring directly through environmental filters, but here the authors suggest that the environmental filter acts through movement limitations. Studies integrating landscape heterogeneity and species characteristics will help us better understand metacommunities and species distributions in nature. [ABSTRACT FROM AUTHOR]

Despite asymmetric competition and a wide array of functional similarities, two ecologically important C4 perennial grasses, Andropogon gerardii and Sorghastrum nutans, frequently codominate areas of the mesic tallgrass prairie of the US Great Plains. A subtle difference in their vegetative reproduction strategies may play a role in preventing the exclusion of S. nutans, the presumed weaker competitor in such regions.While A. gerardii vegetative tiller densities peak in the early growing season and decline thereafter (determinate recruitment), those of S. nutans may continue to increase throughout the growing season (indeterminate recruitment), providing a potential avenue for recovery from more intensive early season competition. However, until now these patterns have only been informally observed in the field.We examined the year‐to‐year consistency of growing season vegetative tiller dynamics (measured as seasonal change in tiller densities) of each grass species from an intact tallgrass prairie in Kansas – a site within the core of both species' distributions – over a period of 8 years. Then, to investigate environmental effects on these dynamics, we examined whether they differ across a Kansas landscape varying in topography, fire management regimes, and the abundances of the study species. Finally, we expanded the investigation of environmental effects on growing season tiller dynamics by observing them at the periphery of the species' distributions in central Colorado, where climatic conditions are dryer and the study species' abundances are reduced.Synthesis. We found that the tiller densities of A. gerardii decline within seasons with striking consistency regardless of spatio‐temporal scale or environmental factors (topography and fire regimes). In contrast, we found the seasonal dynamics of S. nutans tiller densities were dependent on environmental factors, with seasonal tiller density increases occurring only within the Kansas populations but not consistent between years. These observations lay the groundwork for establishing differences in tiller recruitment determinacy as a potentially important yet underappreciated mechanism for promoting coexistence and codominance among perennial plant species. [ABSTRACT FROM AUTHOR]

Understanding the current distribution of riparian plant species is essential for predicting their expansions or contractions in response to flow alterations due to climate changes or direct human actions. Riparian vegetation flow response guilds are assemblages of species that have common functional traits and are hypothesised to respond similarly to fluvial disturbance and water availability along rivers. Species distribution models using guilds may be useful within and across catchments, regions, and continents where floristic composition differs.We examined the distribution of riparian vegetation guilds along gradients of depth to groundwater and inundation exceedance probability (EP) on three rivers in the Colorado River basin and modelled the response of each guild to simulated changes in river flows and alluvial groundwater depth.Groundwater guild distribution models were transferable for the tall tree and flood‐tolerant shrub guilds, but groundwater depth and EP thresholds differed between reaches. Optimal groundwater levels for tall trees and flood‐tolerant shrubs were shallower in Colorado due to higher floodplain groundwater levels and more gentle sub‐surface groundwater gradients. Riparian vegetation guilds were better predicted by groundwater depth than EP while generalist upland guilds were excluded from areas frequently inundated.Presence of the tall tree guild (e.g., Populus fremontii) was predicted by depth to groundwater at all free‐flowing reaches but was not predicted at the one reach where flows are regulated by an upstream dam. In higher elevation reaches, models predicted riparian vegetation guild occurrences with less accuracy, suggesting the influence of other factors such as competition or water contributions from surrounding hillslopes. Scenarios that imposed a groundwater decline indicated that extinctions of both tall trees and flood‐tolerant shrubs (e.g., Salix exigua) could occur in some reaches, depending on future groundwater contributions from hillslopes and the river.Our study demonstrates that river reaches with different plant species composition can have similar guild compositions and the occurrences of these guilds are predicted by hydrologic conditions. Depth to groundwater had a stronger magnitude effect on guild occurrence, highlighting the importance of this less frequently quantified variable in river studies.Our results suggest that the relationship between riparian flow response guild occurrence and hydrologic conditions are transferable between river reaches with differing flow regime, elevation, and climate for some, but not all guilds. Although guilds may respond in similar ways to groundwater depth and flooding, they are not all well predicted by hydrologic condition alone. Guild distributions may be transferable between river systems, but prediction accuracy increases when models are grouped based on reach‐scale hillslope groundwater contributions, elevation, and valley setting. [ABSTRACT FROM AUTHOR]

Theoretical models suggest that infectious diseases could play a substantial role in determining the spatial extent of host species, but few studies have collected the empirical data required to test this hypothesis. Pathogens that sterilize their hosts or spread through frequency‐dependent transmission could have especially strong effects on the limits of species' distributions because diseased hosts that are sterilized but not killed may continue to produce infectious stages and frequency‐dependent transmission mechanisms are effective even at very low population densities. We collected spatial pathogen prevalence data and population abundance data for alpine carnations infected by the sterilizing pathogen Microbotryum dianthorum, a parasite that is spread through both frequency‐dependent (vector‐borne) and density‐dependent (aerial spore transmission) mechanisms. Our 13‐year study reveals rapid declines in population abundance without a compensatory decrease in pathogen prevalence. We apply a stochastic, spatial model of parasite spread that accommodates spatial habitat heterogeneity to investigate how the population dynamics depend on multimodal (frequency‐dependent and density‐dependent) transmission. We found that the observed rate of population decline could plausibly be explained by multimodal transmission, but is unlikely to be explained by either frequency‐dependent or density‐dependent mechanisms alone. Multimodal pathogen transmission rates high enough to explain the observed decline predicted that eventual local extinction of the host species is highly likely. Our results add to a growing body of literature showing how multimodal transmission can constrain species distributions in nature. [ABSTRACT FROM AUTHOR]

Bangladesh is at the ecological transition between the Indo-Himalayan and Indo-Chinese subregions. The country also has one of the highest human population densities in the world and only 6% remaining natural habitat, putting much of its biodiversity at risk. With more than 1455 species worldwide, bats are an important, but threatened, component of global biodiversity and provide critical ecosystem services. Yet, there is no comprehensive work on species occurrence, diversity, or richness of bats of Bangladesh. Here, we collated data on the bats of Bangladesh and states in neighboring countries from the available literature, the Global Biodiversity Information Facility, and museum databases to assess the probability of occurrence of bat species in Bangladesh and created distribution maps for each species. We confirmed 31 species from 8 families, of which 22 were associated with voucher specimens and 9 recorded based on photographs, or human observation. A further 81 species were categorized as Highly Probable (38 species), Probable (33), and Possible (10) in Bangladesh based on the distribution in neighboring states and habitat preferences. The shortfall in confirmed versus potential species highlights the need for rigorous surveys to fully document and characterize the bat diversity of Bangladesh. [ABSTRACT FROM AUTHOR]

As a consequence of anthropogenic climate change, marine species on continental shelves around the world are rapidly shifting deeper and poleward. However, whether these shifts deeper and poleward will allow species to access more, less, or equivalent amounts of continental shelf area and associated critical habitats remains unclear. By examining the proportion of seabed area at a range of depths for each large marine ecosystem (LME), we found that shelf area declined monotonically for 19% of LMEs examined. However, the majority exhibited a greater proportion of shelf area in mid‐depths or across several depth ranges. By comparing continental shelf area across 2° latitudinal bands, we found that all coastlines exhibit multiple instances of shelf area expansion and contraction, which have the potential to promote or restrict poleward movement of marine species. Along most coastlines, overall shelf habitat increases or exhibits no significant change moving towards the poles. The exception is the Southern West Pacific, which experiences an overall loss of area with increasing latitude. Changes in continental shelf area availability across latitudes and depths are likely to affect the number of species local ecosystems can support. These geometric analyses help identify regions of conservation priority and ecological communities most likely to face attrition or expansion due to variations in available area [ABSTRACT FROM AUTHOR]

Critical thermal limits (CTLs) constrain the performance of organisms, shaping their abundance, current distributions, and future distributions. Consequently, CTLs may also determine the quality of ecosystem services as well as organismal and ecosystem vulnerability to climate change. As some of the most ubiquitous animals in terrestrial ecosystems, ants are important members of ecological communities. In recent years, an increasing body of research has explored ant physiological thermal limits. However, these CTL data tend to centre on a few species and biogeographical regions. To encourage an expansion of perspectives, we herein review the factors that determine ant CTLs and examine their effects on present and future species distributions and ecosystem processes. Special emphasis is placed on the implications of CTLs for safeguarding ant diversity and ant‐mediated ecosystem services in the future. First, we compile, quantify, and categorise studies on ant CTLs based on study taxon, biogeographical region, methodology, and study question. Second, we use this comprehensive database to analyse the abiotic and biotic factors shaping ant CTLs. Our results highlight how CTLs may affect future distribution patterns and ecological performance in ants. Additionally, we identify the greatest remaining gaps in knowledge and create a research roadmap to promote rapid advances in this field of study. [ABSTRACT FROM AUTHOR]

Background: Understanding the factors that influence microbes' environmental distributions is important for determining drivers of microbial community composition. These include environmental variables like temperature and pH, and higher-dimensional variables like geographic distance and host species phylogeny. In microbial ecology, "specificity" is often described in the context of symbiotic or host parasitic interactions, but specificity can be more broadly used to describe the extent to which a species occupies a narrower range of an environmental variable than expected by chance. Using a standardization we describe here, Rao's (Theor Popul Biol, 1982. https://doi.org/10.1016/0040-5809(82)90004-1, Sankhya A, 2010. https://doi.org/10.1007/s13171-010-0016-3) Quadratic Entropy can be conveniently applied to calculate specificity of a feature, such as a species, to many different environmental variables. Results: We present our R package specificity for performing the above analyses, and apply it to four real-life microbial data sets to demonstrate its application. We found that many fungi within the leaves of native Hawaiian plants had strong specificity to rainfall and elevation, even though these variables showed minimal importance in a previous analysis of fungal beta-diversity. In Antarctic cryoconite holes, our tool revealed that many bacteria have specificity to co-occurring algal community composition. Similarly, in the human gut microbiome, many bacteria showed specificity to the composition of bile acids. Finally, our analysis of the Earth Microbiome Project data set showed that most bacteria show strong ontological specificity to sample type. Our software performed as expected on synthetic data as well. Conclusions: specificity is well-suited to analysis of microbiome data, both in synthetic test cases, and across multiple environment types and experimental designs. The analysis and software we present here can reveal patterns in microbial taxa that may not be evident from a community-level perspective. These insights can also be visualized and interactively shared among researchers using specificity's companion package, specificity.shiny. [ABSTRACT FROM AUTHOR]

Aim: Temperate marine systems globally are warming at accelerating rates, facilitating the poleward movement of warm‐water species, which are tropicalizing higher‐latitude reefs. While temperature plays a key role in structuring species distributions, less is known about how species' early life stages are responding to warming‐induced changes in preferred nursery habitat availability. We aim to identify key ecological and environmental drivers of juvenile reef fishes' distributions in the context of ocean warming. Location: South‐eastern Australian coastline from 30 to 37°S. Methods: We used a decade of underwater visual census data to uncover latitudinal distribution patterns of juvenile reef fishes and habitats across 1000 km of coastline, from subtropical to temperate latitudes. We modelled how benthic habitat cover, depth, wave exposure and sea surface temperature influence distributions of warm‐water and cool‐water juvenile reef fishes on temperate rocky reefs. Results: We found sea surface temperature was typically the most important factor influencing densities of juvenile fishes, regardless of species' thermal affinity or latitudinal range extent. Juveniles of tropical and subtropical range‐expanding fishes responded more strongly to warmer temperatures and lower wave exposure, while juveniles of temperate species responded more strongly to benthic habitats. Species' responses to greater availability of temperate reef habitat‐formers such as kelp and other macroalgae contrasted, being positive for temperate and negative for tropical and subtropical juvenile fishes. Main conclusions: The availability of both suitable habitat and sea temperatures for species' early life stages is important considerations when predicting changes in reef fishes' distributions in the context of ocean warming. Warming‐induced isotherm shifts and feedback loops constraining the persistence of key temperate reef habitat‐formers will favour range‐expanding tropical reef fishes colonizing higher‐latitude reefs, while disadvantaging some macroalgal‐associated resident temperate species. Such varying responses to warming‐induced environmental changes may strongly influence the structure of emerging tropicalized reef assemblages. [ABSTRACT FROM AUTHOR]

Species distribution patterns in the Brazilian Marine Province (BMP) are extensively debated, nevertheless no study used a multi-taxa approach to investigate possible biotic distinctions and the role of environmental factors in determining biogeographical patterns in this province. Here, we compiled the largest distributional multi-taxa dataset in the southern Atlantic (2412 reef species) to address the following: (1) similarities among areas accounting for species composition and environmental characteristics; (2) the absolute species richness of nine taxonomic groups among geographical bins; and (3) how species biogeographical patterns are explained by the environmental similarities. We hypothesized sub-provinces' limits will be strongly correlated to environmental delimitations, being sea surface temperature a central component influencing biotic subdivision on the BMP. We found eight different geographical bins considering the environmental factors, while five considering species distributions. We also observed a latitudinal gradient of species richness for most taxa, some presenting a "mid-domain" shape pattern. Beta diversity among sub-provinces was low, and the nestedness component more important, indicating high connectivity along the BMP. Using a db-RDA, we demonstrated that environmental variables explained 64% of species clustering patterns, with sea surface temperature, water turbidity and current velocity explaining the biotic clustering of the Brazilian northeastern coast. Sub-provinces North and Abrolhos Bank were the most distinct areas regarding environmental and biotic data. Our study highlights the importance of using a multi-taxa approach to understand the relationship between biogeographical patterns, as well as its response to environmental and historical factors. [ABSTRACT FROM AUTHOR]

Aim: Comprehensive, global information on species' occurrences is an essential biodiversity variable and central to a range of applications in ecology, evolution, biogeography and conservation. Expert range maps often represent a species' only available distributional information and play an increasing role in conservation assessments and macroecology. We provide global range maps for the native ranges of all extant mammal species harmonised to the taxonomy of the Mammal Diversity Database (MDD) mobilised from two sources, the Handbook of the Mammals of the World (HMW) and the Illustrated Checklist of the Mammals of the World (CMW). Location: Global. Taxon All extant mammal species. Methods: Range maps were digitally interpreted, georeferenced, error‐checked and subsequently taxonomically aligned between the HMW (6253 species), the CMW (6431 species) and the MDD taxonomies (6362 species). Results: Range maps can be evaluated and visualised in an online map browser at Map of Life (mol.org) and accessed for individual or batch download for non‐commercial use. Main conclusion: Expert maps of species' global distributions are limited in their spatial detail and temporal specificity, but form a useful basis for broad‐scale characterizations and model‐based integration with other data. We provide georeferenced range maps for the native ranges of all extant mammal species as shapefiles, with species‐level metadata and source information packaged together in geodatabase format. Across the three taxonomic sources our maps entail, there are 1784 taxonomic name differences compared to the maps currently available on the IUCN Red List website. The expert maps provided here are harmonised to the MDD taxonomic authority and linked to a community of online tools that will enable transparent future updates and version control. [ABSTRACT FROM AUTHOR]

Both abiotic and biotic drivers influence species distributions. Abiotic drivers such as climate have received considerable attention, even though biotic drivers such as hybridization often interact with abiotic drivers. We sought to explore the (1) costs of co‐occurrence for ecologically similar species that hybridize and (2) associations between ecological factors and condition to understand how abiotic and biotic factors influence species distributions. For two closely related and ecologically similar songbirds, black‐capped and mountain chickadees, we characterized body condition, as a proxy for fitness, using a 1358‐individual range‐wide dataset. We compared body condition in sympatry and allopatry with several abiotic and biotic factors using species‐specific generalized linear mixed models. We generated genomic data for a subset of 217 individuals to determine the extent of hybridization‐driven admixture in our dataset. Within this data subset, we found that ~11% of the chickadees had hybrid ancestry, and all hybrid individuals had typical black‐capped chickadee plumage. In the full dataset, we found that birds of both species, independent of demographic and abiotic factors, had significantly lower body condition when occurring in sympatry than birds in allopatry. This could be driven by either the inclusion of cryptic, likely poor condition, hybrids in our full dataset, competitive interactions in sympatry, or range edge effects. We are currently unable to discriminate between these mechanisms. Our findings have implications for mountain chickadees in particular, which will encounter more black‐capped chickadees as black‐capped chickadee ranges shift upslope and could lead to local declines in mountain chickadee populations. [ABSTRACT FROM AUTHOR]

Image recording is now ubiquitous in the fields of endangered-animal conservation and GIS. However, endangered animals are rarely seen, and, thus, only a few samples of images of them are available. In particular, the study of endangered-animal detection has a vital spatial component. We propose an adaptive, few-shot learning approach to endangered-animal detection through data augmentation by applying constraints on the mixture of foreground and background images based on species distributions. First, the pre-trained, salient network U2-Net segments the foregrounds and backgrounds of images of endangered animals. Then, the pre-trained image completion network CR-Fill is used to repair the incomplete environment. Furthermore, our approach identifies a foreground–background mixture of different images to produce multiple new image examples, using the relation network to permit a more realistic mixture of foreground and background images. It does not require further supervision, and it is easy to embed into existing networks, which learn to compensate for the uncertainties and nonstationarities of few-shot learning. Our experimental results are in excellent agreement with theoretical predictions by different evaluation metrics, and they unveil the future potential of video surveillance to address endangered-animal detection in studies of their behavior and conservation. [ABSTRACT FROM AUTHOR]

All species inevitably leave genetic traces in their environments, and the resulting environmental DNA (eDNA) reflects the species present in a given habitat. It remains unclear whether eDNA signals can provide quantitative metrics of abundance on which human livelihoods or conservation successes depend. Here, we report the results of a large eDNA ocean survey (spanning 86 000 km2 to depths of 500 m) to understand the abundance and distribution of Pacific hake (Merluccius productus), the target of the largest finfish fishery along the west coast of the USA. We sampled eDNA in parallel with a traditional acoustic-trawl survey to assess the value of eDNA surveys at a scale relevant to fisheries management. Despite local differences, the two methods yield comparable information about the broad-scale spatial distribution and abundance. Furthermore, we find depth and spatial patterns of eDNA closely correspond to acoustic-trawl estimates for hake. We demonstrate the power and efficacy of eDNA sampling for estimating abundance and distribution and move the analysis eDNA data beyond sample-to-sample comparisons to management relevant scales. We posit that eDNA methods are capable of providing general quantitative applications that will prove especially valuable in data- or resource-limited contexts. [ABSTRACT FROM AUTHOR]

Sexual reproduction often declines towards range edges, reducing fitness, dispersal and adaptive potential. For plants, sexual reproduction is frequently limited by inadequate pollination. While case studies show that pollen limitation can limit plant distributions, the extent to which pollination commonly declines towards plant range edges is unknown. Here, we use global databases of pollen-supplementation experiments and plant occurrence data to test whether pollen limitation increases towards plant range edges, using a phylogenetically controlled meta-analysis. While there was significant pollen limitation across studies, we found little evidence that pollen limitation increases towards plant range edges. Pollen limitation was not stronger towards the tropics, nor at species' equatorward versus poleward range limits. Meta-analysis results are consistent with results from targeted experiments, in which pollen limitation increased significantly towards only 14% of 14 plant range edges, suggesting that pollination contributes to range limits less often than do other interactions. Together, these results suggest pollination is one of the rich variety of potential ecological factors that can contribute to range limits, rather than a generally important constraint on plant distributions. This article is part of the theme issue 'Species' ranges in the face of changing environments (part I)'. [ABSTRACT FROM AUTHOR]

Biological communities in the Arctic are changing through the climate‐driven encroachment of subarctic species. This "Atlantification" extends to keystone Calanoid copepods, as the small‐bodied Calanus finmarchicus increases in abundance in areas where it overlaps with larger Arctic congeners. The environmental factors that are facilitating this shift, whether related to optimal conditions in temperature or seasonality, remain unclear. Assessing these drivers at an Arctic‐wide scale is necessary to predict future ecosystem change and impacts. Here we have compiled range‐wide occurrences of C. finmarchicus and a suite of seasonal biophysical climatologies to build a boreo‐Arctic ecological niche model. The data set was divided into two eras, 1955–1984 and 1985–2017, and an optimized MaxEnt model was used to predict the seasonal distribution of the abiotic niche of C. finmarchicus in both eras. Comparing outputs between eras reveals an increase in habitat suitability at the Arctic range edge. Large and significant increases in suitability are predicted in the regions of the Greenland, Labrador, and Southern Barents Seas that have experienced reduced sea‐ice cover. With the exception of the Barents Sea, these areas also show a seasonal shift in the timing of peak habitat suitability toward an earlier season. Our findings suggest that the Atlantification of Arctic zooplankton communities is accompanied by climate‐driven phenology changes. Although seasonality is a critical constraint to the establishment of C. finmarchicus at Arctic latitudes, earlier sea‐ice retreat and associated productivity is making these environments increasingly favorable for this subarctic species. [ABSTRACT FROM AUTHOR]

Estimates of the percentage of species "committed to extinction" by climate change range from 15% to 37%. The question is whether factors other than climate need to be included in models predicting species' range change. We created demographic range models that include climate vs. climate‐plus‐competition, evaluating their influence on the geographic distribution of Pinus edulis, a pine endemic to the semiarid southwestern U.S. Analyses of data on 23,426 trees in 1941 forest inventory plots support the inclusion of competition in range models. However, climate and competition together only partially explain this species' distribution. Instead, the evidence suggests that climate affects other range‐limiting processes, including landscape‐scale, spatial processes such as disturbances and antagonistic biotic interactions. Complex effects of climate on species distributions—through indirect effects, interactions, and feedbacks—are likely to cause sudden changes in abundance and distribution that are not predictable from a climate‐only perspective. [ABSTRACT FROM AUTHOR]