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A gap still exists in published data on variation of morphological and ecological traits for common bird species over a large area. To diminish this knowledge gap, we report here average values of 99 bird species from three sites in Germany from the Biodiversity Exploratories on 24 ecological and functional traits. We present our own data on morphological and ecological traits of 28 common bird species and provide additional measurements for further species from published studies. This is a unique data set from live birds, which has not been published and is available neither from museum nor from any other collection in the presented coverage. Dataset: available as the supplementary file. Dataset license: CC-BY

A diverse microbial assemblage in the ocean is responsible for nearly half of global primary production. It has been hypothesized and experimentally demonstrated that nutrient loading can stimulate blooms of large eukaryotic phytoplankton in oligotrophic systems. Although central to balancing biogeochemical models, knowledge of the metabolic traits that govern the dynamics of these bloom-forming phytoplankton is limited. We used eukaryotic metatranscriptomic techniques to identify the metabolic basis of functional group-specific traits that may drive the shift between net heterotrophy and autotrophy in the oligotrophic ocean. Replicated blooms were simulated by deep seawater (DSW) addition to mimic nutrient loading in the North Pacific Subtropical Gyre, and the transcriptional responses of phytoplankton functional groups were assayed. Responses of the diatom, haptophyte, and dinoflagellate functional groups in simulated blooms were unique, with diatoms and haptophytes significantly (95% confidence) shifting their quantitative metabolic fingerprint from the in situ condition, whereas dinoflagellates showed little response. Significantly differentially abundant genes identified the importance of colimitation by nutrients, metals, and vitamins in eukaryotic phytoplankton metabolism and bloom formation in this system. The variable transcript allocation ratio, used to quantify transcript reallocation following DSW amendment, differed for diatoms and haptophytes, reflecting the longstanding paradigm of phytoplankton r- and K-type growth strategies. Although the underlying metabolic potential of the large eukaryotic phytoplankton was consistently present, the lack of a bloom during the study period suggests a crucial dependence on physical and biogeochemical forcing, which are susceptible to alteration with changing climate. [ABSTRACT FROM AUTHOR]

Identifying the ecological and life-history traits that render species vulnerable to fragmentation is an important prerequisite for the development of effective conservation strategies to minimize future biodiversity losses. When determining how species traits influence vulnerability to fragmentation, however, several important confounding factors such as detectability and synergistic effects among traits are rarely considered. In this study, after controlling for these methodological shortcomings, we determined how species traits influenced fragmentation vulnerability using bird data collected from islands created by the inundation of the Thousand Island Lake, China. We obtained eight species traits from field surveys and from the literature: natural abundance, geographical range size, habitat specificity, body size, trophic level, mobility, fecundity, and nest type. After phylogenetic correction, these traits were used separately and in combination to assess their associations with the index of fragmentation vulnerability, the proportion of islands occupied. Inclusion of detectability in analysis resulted in considerable increases in overall island occupancy for all species in general and for cryptic species in particular. Accounting for detectability altered the rank of best models and thus influenced the identification of the relationships between species traits and fragmentation vulnerability. We found synergistic interactions between natural abundance and habitat specificity. Our findings highlight the importance of incorporating detectability and synergistic effects among traits into future studies. From a conservation perspective, our results suggest that we should give priority conservation efforts to rare species with low natural abundance and high habitat specificity. [ABSTRACT FROM AUTHOR]

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Aim Disentangling the contributions of niche and dispersal processes as species distribution drivers is crucial from both theoretical and practical standpoints. We investigated whether niche-related and dispersal-related functional traits of 19 beetle clades were good predictors of beta diversity patterns across continental European countries. Location Continental Europe. Methods We quantified the overall compositional heterogeneity (a measure of multiple-site dissimilarity) of each beetle clade in continental Europe and assessed its relationship with body size and the proportion of wingless species as proxies for dispersal ability. Overall compositional heterogeneity was also compared with trophic and habitat preferences of clades as proxies for their ecological specialization. Additionally, beta diversity patterns were characterized as a multivariate pairwise dissimilarity matrix among pairs of countries for each beetle clade. We assessed whether differences among these pairwise structures were related to dispersal ability or the ecological specialization of clades. The turnover and nestedness-resultant components of compositional dissimilarity were calculated separately for all analyses. Results The dispersal ability and ecological specialization explained a large proportion (> 70%) of the variation in overall compositional heterogeneity but a lower proportion ( c. 40%) of the variation in the multivariate pairwise structures. Remarkably, the explained variation was shared between both sets of predictors in the case of overall compositional heterogeneity but was independently related to dispersal ability or ecological specialization for the multivariate pairwise structure analysis. Main conclusions These results suggest a tight relationship between ecological specialization, dispersal ability and compositional heterogeneity of European beetle clades. However, the specific patterns of dissimilarities between pairs of countries seem to be determined independently by either ecological or dispersal processes and seem to be subject to other unmeasured factors. [ABSTRACT FROM AUTHOR]

Fishers' perceptions of changes in grouper size and abundance were compared with scientific data collected via underwater visual censuses (UVCs) before (1995) and after (2006 and 2011) the establishment of the Mafia Island Marine Park. Perceptions on changes in the size structure of groupers differed among communities due to differences in fishing capacities. Fishers in one village had mixed perceptions, while in another village the majority (66%) perceived a decline in size, with small groupers dominating the catch. Similarly, UVCs indicated that size structure was dominated by small groupers at all times surveyed. Consistent with fishers' perceptions, UVC indicated that biomass and abundance of groupers declined in both no-take zones (NTZs) and specified-use zones (SUZs) between 1995 and 2006, with no substantial changes between 2006 and 2011. The NTZs had higher density and diversity of grouper species than SUZs, as would be expected from the differences in bottom topography in these two types of areas. The idea that NTZs could increase the biomass and abundance of groupers to benefit fished zones was not found, thus indicating that NTZs are not necessarily the best option for managing reef fisheries. [ABSTRACT FROM AUTHOR]

In agriculture-dominated landscapes, agricultural intensification and associated landscape homogenization have caused large declines in farmland biodiversity. This study was aimed at determining how agricultural landscape composition drives community diversity and composition of farmland birds in the characteristic bocage landscape in Brittany (NW France) on a broad scale. Using bird atlas data from the region (2004–2008; 10 × 10 km), we analyzed the importance of different components of agricultural landscape composition (types of crops, amount of semi-natural covers and elements, and artificial lands) on the alpha diversity and beta diversity of farmland birds of different functional groups, defined depending on the degree of farmland specialization and ecological requirements. Agricultural landscape composition features explained a small amount of variation in alpha and beta diversity, particularly for specialists and residents. Cereal crops were negatively correlated with alpha diversity of all the functional groups considered whereas rotational grasslands were negatively associated with migrant and insectivorous alpha diversity. Although shrublands are not common in Brittany, they were positively associated with the occurrence of some species and particularly with alpha diversity of all the functional groups but specialists and residents. At the spatial grain of analysis, community composition was mainly driven by a gradient of alteration of the bocage . To conclude, we claim for the consideration of regional idiosyncrasies in far-reaching planning schemes to prevent future biodiversity loss in agriculture-dominated landscapes due to agricultural intensification. In view of the observed large-scale trends gathered from atlas data analysis and the small amount of explained variation, we also advocate for subsequent finer scale bespoke surveys to determine the biodiversity status associated with the valuable bocage agricultural landscape. [ABSTRACT FROM AUTHOR]

Apple orchards are agro-ecosystems managed with high levels of inputs and especially pesticides. Epigeal spider communities were sampled in three seasons using pitfall traps in 19 apple orchards with four different management strategies (abandoned, under organic, Integrated Pest Management or conventional protection) and thus significantly different pesticide usage. The abundance and diversity of the spider communities was the highest in abandoned orchards. Higher diversity and evenness values were the only difference in spider communities from the organic orchards compared to the other commercial orchards. The analysis of five ecological traits (proportion of aeronauts, type of diet, overwintering stages, body size and maternal care), however, clearly showed differences in the spiders from the organic orchards. The spider species in the other commercial orchards were smaller and have higher dispersal abilities. Seven bioindicator species were identified in abandoned orchards, two species in organic ones (only Lycosidae) and one species in conventional orchards (Linyphiidae). [ABSTRACT FROM AUTHOR]

Fine-scale vegetation cover is a common variable used to explain animal occurrence, but we know less about the effects of fine-scale vegetation heterogeneity. Theoretically, fine-scale vegetation heterogeneity is an important driver of biodiversity because it captures the range of resources available in a given area. In this study we investigated how bird species richness and birds grouped by various ecological traits responded to vegetation cover and heterogeneity. We found that both fine-scale vegetation cover (of tall trees, medium-sized trees and shrubs) and heterogeneity (of tall trees, and shrubs) were important predictors of bird richness, but the direction of the response of bird richness to shrub heterogeneity differed between sites with different proportions of tall tree cover. For example, bird richness increased with shrub heterogeneity in sites with high levels of tall tree cover, but declined in sites with low levels of tall tree cover. Our findings indicated that an increase in vegetation heterogeneity will not always result in an increase in resources and niches, and associated higher species richness. We also found birds grouped by traits responded in a predictable way to vegetation heterogeneity. For example, we found small birds benefited from increased shrub heterogeneity supporting the textual discontinuity hypothesis and non-arboreal (ground or shrub) nesting species were associated with high vegetation cover (low heterogeneity). Our results indicated that focusing solely on increasing vegetation cover (e.g. through restoration) may be detrimental to particular animal groups. Findings from this investigation can help guide habitat management for different functional groups of birds. [ABSTRACT FROM AUTHOR]

• Despite using abundance data, the models' temporal transferability is still poor. • Using traditional variables of land cover does not predict changes in most birds. • Few ecological traits seem to significantly impact the models' transferability. Species distribution models have become important tools for studying changes in biodiversity. Most studies use these models to evaluate the impact of global changes on biodiversity. For that purpose, scenarios are used that are based on changes in land use and/or land cover, or on climatic changes. However, the temporal transferability of such models depends heavily on modeling methods, environmental predictors and the ecological traits of species. Here, we evaluate the power of modeling tools to predict changes in bird species abundances based on observed changes in land cover. Wallonia, Belgium To assess this temporal transferability, this research makes use of two biological and two environmental datasets, both sampled with a 10-year interval. This allows us to compare the predictions of models for another period than the period used to fit the models, with actual values for species abundance. We also analyzed the impact of ecological traits on the temporal transferability. Generalized additive models were fitted for 75 breeding birds. While a lot of studies use occurrence data, we used abundance data for fitting models. Abundance data contains more information and should allow us to better capture abundance changes in bird populations. For the majority of species studied, the results show a low temporal transferability. With a few exceptions, e.g., species with softwood habitats, predicted changes do not correspond to observed changes. For certain bird species, e.g., those on arable lands, we observed an increase in predicted abundances in the future, while these species actually decreased. Few ecological traits seem to significantly impact the models' transferability. Our findings show that it is difficult to predict abundance changes of bird species based only on land cover changes. It is necessary to add other predictors into the models, e.g., predictors of habitat quality or spatial configuration. [ABSTRACT FROM AUTHOR]

Since the floristic study of lichens at the Barton and Weaver Peninsulas of King George Island in 2006, there have been intense investigations of the lichen flora of the two peninsulas as well as that of Fildes Peninsula and Ardley Island in Maxwell Bay, King George Island, South Shetland Islands, maritime Antarctic. In this study, a total of 104 species belonging to 53 genera, are identified from investigations of lichens that were collected in austral summer seasons from 2008 to 2016. Phenotypic and molecular analyses were incorporated for taxonomic identification. In particular, 31 species are found to be endemic to the Antarctic and 22 species are newly recorded to the Maxwell Bay region. Lepra dactylina, Stereocaulon caespitosum, and Wahlenbergiella striatula are newly recorded in the Antarctic, and the previously reported taxon Cladonia furcata is excluded from the formerly recorded list due to misidentification. We also provide ecological and geographical information about lichen associations and habitat preferences., (© 2023. The Author(s).)

Performance trade-offs between competition and colonization can be an important mechanism facilitating regional coexistence of competitors. However, empirical evidence for this trade-off is mixed, raising questions about the extent to which it shapes diverse ecological communities. Here, we outline a framework that can be used to improve empirical tests of the competition-colonization trade-off. We argue that tests of the competition-colonization trade-off have been diverted into unproductive paths when dispersal mode and/or competition type have been inadequately defined. To generate comparative predictions of associations between dispersal and competitive performance, we develop a conceptual trait-based framework that clarifies how dispersal mode and type of competitor shape this trade-off at the stage of dispersal and establishment in a variety of systems. Our framework suggests that competition-colonization trade-offs may be less common for passively dispersing organisms when competitive dominants are those best able to withstand resource depletion (competitive response), and for active dispersers when traits for dispersal performance are positively associated with resource pre-emption (competitive effect). The framework presented here is designed to provide common ground for researchers working in different systems in order to prompt more effective assessment of this performance trade-off and its role in shaping community structure. By delineating key system properties that mediate the trade-off between competitive and colonization performance and their relationship to individual-level traits, researchers in disparate systems can structure their predictions about this trade-off more effectively and compare across systems more clearly., (© 2022 The Authors. Journal of Animal Ecology © 2022 British Ecological Society.)

Although vicariant processes are expected to leave similar genomic signatures among codistributed taxa, ecological traits such as habitat and stratum can influence genetic divergence within species. Here, we combined landscape history and habitat specialization to understand the historical and ecological factors responsible for current levels of genetic divergence in three species of birds specialized in seasonally flooded habitats in muddy rivers and which are widespread in the Amazon basin but have isolated populations in the Rio Branco. Populations of the white-bellied spinetail (Mazaria propinqua), lesser wagtail-tyrant (Stigmatura napensis) and bicolored conebill (Conirostrum bicolor) are currently isolated in the Rio Branco by the black-waters of the lower Rio Negro, offering a unique opportunity to test the effect of river colour as a barrier to gene flow. We used ultraconserved elements (UCEs) to test alternative hypotheses of population history in a comparative phylogeographical approach by modelling genetic structure, demographic history and testing for shared divergence time among codistributed taxa. Our analyses revealed that (i) all three populations from the Rio Branco floodplains are genetically distinct from other populations along the Amazon River floodplains; (ii) these divergences are the result of at least two distinct events, consistent with species habitat specialization; and (iii) the most likely model of population evolution includes lower population connectivity during the Late Pleistocene transition (~250,000 years ago), with gene flow being completely disrupted after the Last Glacial Maximum (~21,000 years ago). Our findings highlight how landscape evolution modulates population connectivity in habitat specialist species and how organisms can have different responses to the same historical processes of environmental change, depending on their habitat affinity., (© 2022 John Wiley & Sons Ltd.)

We studied carabid beetle assemblages found in riparian black alder forests in the Sila plateau (Southern Apennines). These carabid assemblages are characterized by a high incidence of endemic small-sized, low dispersal, highly stenotopic (hygrophilic), and trophycally specialized species. To evaluate the influence of anthropogenic disturbance on these insects, we compared carabid assemblage of an old undisturbed forest (65-170y, wilderness landscape) with that of a younger, partly grazed stand (40-60y, cropland landscape). The carabid assemblage of the disturbed stand was characterized by a higher number of species, but showed a lower incidence of zoophagous specialists and brachypterous beetles, with many species probably coming from an adjacent cropland. However, the disturbed stand maintains almost 80% of the core species found in the older forest, which suggests that these insects are not particularly sensitive to disturbance factors represented by periodic wood harvesting and extensive cattle grazing. [ABSTRACT FROM AUTHOR]

The impacts of introduced mammalian predators on the viability of bird populations in forest, river and coastal habitats in New Zealand are well known. However, a common understanding of their impacts in freshwater wetlands is lacking. We review evidence for impacts of introduced mammalian predators on freshwater birds, particularly specialist species restricted to wetlands, and use this information to make predictions about freshwater species likely to be vulnerable to predation. Extinctions and significant declines of freshwater species have been numerous since humans introduced mammalian predators to New Zealand. Anecdotal evidence links predation to the loss of 11 of 14 extinct birds that would have inhabited wetlands. Thirty extant species, particularly ground-nesting species, are still under threat from mammalian predators. All introduced mammalian predator species are abundant and/or widespread in New Zealand wetlands and most have been confirmed to prey upon freshwater bird species. While their precise impacts on the long-term viability of threatened bird populations have not been evaluated, evidence suggests that predation is a serious threat, warranting predator control. An evaluation using documented predation events and ecological traits suggests that six threatened wetland specialists are at high risk of predation: Australasian bittern (Botaurus poiciloptilus), banded rail (Gallirallus philippensis), brown teal (Anas chlorotis), fernbird (Bowdleria punctata), marsh crake (Porzana pusilla), and spotless crake (P. tabuensis). Research is needed on the ecology and behaviour of mammalian predators in wetlands to help understand their impacts on long-term viability of bird populations and to assist in developing and monitoring predator control programmes. [ABSTRACT FROM AUTHOR]

Biological indicator methods represent one of the most effective and widely used strategies for understanding the influences of environmental degradation on biodiversity in various landscapes. Researchers and land managers generally assume that the present distributions of biological indicator species are influenced by the current environment. However, recent studies have suggested the importance of past environments to species distributions (i.e., a time lag between changes in species distribution and habitat alterations). Therefore, it is necessary to understand the effects of past environments on the distributions of indicator species. We conducted a survey on the Tokachi Plain in Hokkaido, Japan. We targeted two taxa that have been widely used as indicator species (carabid beetles and bats) and investigated whether past landscape environments influenced their present distributions. We showed that past landscape environments (5 decades prior to the present) influenced the distributions of some ecological trait groups in each taxon (large body size for carabid beetles and a 25 kHz peak echolocation frequency for bats) and that these effects varied among groups. Our results suggest the need to consider the dynamics of land-use changes and the effects of past environments on the distributions of indicator taxa, otherwise we may misunderstand the effects of environmental degradation on biodiversity. [ABSTRACT FROM AUTHOR]

Comparative studies on clonal and genetic structure between ecologically contrasting congeners may provide valuable insights into the mechanisms promoting the maintenance of genetic diversity in clonal plant species. Polygonatum stenophyllum has long rhizomes (ca. 30–40cm long) and largely occurs on sandy soils in open river banks, whereas its congener Polygonatum inflatum has short ones (ca. 5–10cm long) and occurs on humic soils under deciduous forests. Using 21 allozyme loci, we comparatively assessed levels of clonal and genetic diversity in the 2 clonal species. Seven populations of P. stenophyllum consisted of single clones, and levels of within-population clonal and genetic variation were considerably lower than those of P. inflatum. However, when samples were pooled, P. stenophyllum harbored higher genetic variation than P. inflatum, which is due to higher among-population genetic differentiation in the former species compared with the latter (FST = 0.636 vs. FST = 0.165). Our data suggest that populations of P. stenophyllum have been mainly founded by a single seed or rhizome (through river water) or by a few seeds, whereas populations of P. inflatum would have been established through multiple, repeated seedling recruitment. Moderate levels of genetic diversity in a population of P. stenophyllum located at the foot of the Baekdudaegan Mountains and in all the populations of P. inflatum are consistent with the previous hypothesis that these mountains served as a glacial refugium for many boreal species of the Korean Peninsula. [ABSTRACT FROM PUBLISHER]

The sensitivity of diatom taxonomy and trait-based endpoints to chemicals has been poorly used so far in Environmental Risk Assessment. In this study, diatom assemblages in outdoor flow-through mesocosms were exposed to thiram (35 and 170 μg/L), and a hydrocarbon emulsion (HE; 0.01, 0.4, 2 and 20 mg/L). The effects of exposure were assessed for 12 weeks, including 9 weeks post-treatment, using taxonomic structure and diversity, bioindication indices, biological traits, functional diversity indices, indicator classes and ecological guilds. For both chemicals, diversity increased after the treatment period, and responses of ecological traits were roughly identical with an abundance increase of motile taxa tolerant to organic pollution and decrease of low profile taxa. Bioindication indices were not affected. Traits provided a complementary approach to biomass measurements and taxonomic descriptors, leading to a more comprehensive overview of ecological changes due to organic chemicals, including short- and long-term effects on biofilm structure and functioning. [ABSTRACT FROM AUTHOR]

Background and Aims Plant relative growth rate (RGR) depends on biomass allocation to leaves (leaf mass fraction, LMF), efficient construction of leaf surface area (specific leaf area, SLA) and biomass growth per unit leaf area (net assimilation rate, NAR). Functional groups of species may differ in any of these traits, potentially resulting in (1) differences in mean RGR of groups, and (2) differences in the traits driving RGR variation within each group. We tested these predictions by comparing deciduous and evergreen savanna trees. Methods RGR, changes to biomass allocation and leaf morphology, and root non-structural carbohydrate reserves were evaluated for juveniles of 51 savanna species (34 deciduous, 17 evergreen) grown in a common garden experiment. It was anticipated that drivers of RGR would differ between leaf habit groups because deciduous species have to allocate carbohydrates to storage in roots to be able to flush leaves again, which directly compromises their LMF, whereas evergreen species are not subject to this constraint. Key Results Evergreen species had greater LMF and RGR than deciduous species. Among deciduous species LMF explained 27 % of RGR variation (SLA 34 % and NAR 29 %), whereas among evergreen species LMF explained between 2 and 17 % of RGR variation (SLA 32–35 % and NAR 38–62 %). RGR and LMF were (negatively) related to carbohydrate storage only among deciduous species. Conclusions Trade-offs between investment in carbohydrate reserves and growth occurred only among deciduous species, leading to differences in relative contribution made by the underlying components of RGR between the leaf habit groups. The results suggest that differences in drivers of RGR occur among savanna species because these have different selected strategies for coping with fire disturbance in savannas. It is expected that variation in the drivers of RGR will be found in other functional types that respond differently to particular disturbances. [ABSTRACT FROM AUTHOR]

Ecologically similar species often compete aggressively for shared resources. These interactions are frequently asymmetric, with one species behaviorally dominant to another and excluding it from preferred resources. Despite the potential importance of this type of interference competition as a source of selection, we know little about patterns of trait divergence between dominant and subordinate species. We compiled published data on phylogenetically independent, closely related species of North American birds where one species was consistently dominant in aggressive interactions with a congeneric species. We then compared the body size, breeding phenology, life history, ecological breadth, and biogeography of these species. After accounting for body size and phylogeny, we found repeated patterns of trait divergence between subordinate and dominant species within genera. Subordinate species that migrated seasonally arrived 4-7 days later than dominants on their sympatric breeding grounds, and both resident and migratory subordinates initiated breeding 7-8 days later than their dominant, sympatric congeners. Subordinate species had a 5.2% higher annual adult mortality rate and laid eggs that were 0.02 g heavier for their body mass. Dominant and subordinate species used a similar number of different foods, foraging behaviors, nest sites, and habitats, but subordinates were more specialized in their foraging behaviors compared with closely related dominant species. The breeding and wintering ranges of subordinate species were 571 km farther apart than the ranges of dominant species, suggesting that subordinate species migrate greater distances. Range sizes and latitudinal distributions did not consistently differ, although subordinate species tended to breed farther north or winter farther south. These results are consistent with dominant species directly influencing the ecological strategies of subordinate species (via plastic or genetically based changes), either by restricting their access to resources or simply through aggression. Alternatively, these ecological traits may covary with patterns of behavioral dominance, with no direct consequences of interactions. Regardless of the mechanism, recognizing that the relative position of a species within a dominance hierarchy is correlated with a suite of other ecological and fitness related traits has far-reaching implications for the mechanisms underlying species distributions and the structure of biological assemblages. [ABSTRACT FROM AUTHOR]

In many ways, known and unknown, climate change will affect species' distributions, life cycles, phenologies, and ultimately survival. Lepidoptera are among the organisms that have been shown to be strongly impacted by climate change, and their conservation presents challenges that are both unique and unprecedented. Various studies have sought to determine what ecological and life traits of Lepidoptera influence species' responses to climate change, and here I review the few studies that evaluate such responses over a long period of time for a large number of species for common associations. Species with wider geographic distribution and less habitat specificity are generally considered less vulnerable to climate change, while those with opposite traits are deemed more vulnerable. The latter are more likely to change their phenology in response to climate change. Larval diet breadth and composition, overwintering stage, and adult activity period appear to be consistent predictors of changes in flight phenology. The knowledge of these traits for species of concern allows us to assess the implications of the possible phenological changes, and decide what can be done about those changes. Determining how phenological changes may affect current management or conservation practices and defining actions and priorities can be crucial for the success of a conservation plan. [ABSTRACT FROM AUTHOR]

It is not known if grassy margins contribute to the conservation of biodiversity if situated along organically managed cereal fields as the contrast in environmental conditions between fields and margins may be too small in absence of pesticide applications., Communities of spiders, ground beetles, true bugs and aphids were sampled in 2 years along transects from the centre of organically managed cereal fields into adjacent grassy margins. Based on species richness, abundances, ecological and body size traits of species and taxonomic distinctness between species, communities were compared between organically managed cereal fields and their grassy margins., The species richness, abundance and variation in taxonomic distinctness of true bugs were significantly higher in grassy margins. For spiders and ground beetles, these metrics were either higher in cereal fields or did not differ significantly. At the species level, spiders living under stones or in soil crevices, as well as phytophagous ground beetles and true bugs that overwinter as eggs benefited from grassy margins. True bug communities in cereal fields were dominated by a few abundant species, whereas communities in margins were rather dominated by a few large species., Our comprehensive analyses highlight the importance of accounting for species identities and biology in biodiversity studies. The traits that characterised arthropod species that benefited from margins are not characteristic for pest species. Grassy margins along organic fields therefore represent an important agri-environmental scheme for the conservation of several arthropod taxa and margins should not be removed to increase the crop production area in organically managed cereal fields. [ABSTRACT FROM AUTHOR]

Understanding ecological traits of species associated with vulnerability to habitat fragmentation is important for the development of effective conservation efforts. However, few studies have examined ecological correlates of vulnerability to fragmentation among tropical small mammals at fine spatial scales. Here we use random forests and regression tree models to identify ecological correlates of vulnerability to fragmentation among terrestrial small mammal species across 2 networks of forest fragments in the East and West Usambara Mountains, Tanzania. Small mammal species vary considerably in their vulnerability to fragmentation as assessed by species occupancy and change in abundance. Random forests models indicate that matrix use is the highest-ranked predictor of vulnerability to fragmentation with small mammal species that do not use or use few matrix habitat types, being more vulnerable to fragmentation than species that use all adjacent matrix habitat types. Our results emphasize the importance of local-scale approaches for designing conservation strategies for Afrotropical small mammal species. [ABSTRACT FROM AUTHOR]

Abstract: The main Korean mountain range (the so-called “Baekdudaegan”), which stretches from north to south across most of the country, has been thought to harbor glacial refugia for boreal plant species, where they likely found relatively stable habitats and maintained large population sizes. Under this scenario, high levels of genetic variation and low or moderate degree of differentiation among populations within these species were expected. To test this hypothesis, we examined levels of allozyme diversity (14 loci) in eight populations of the boreal herb Lilium cernuum, which in Korea occurs largely along the Baekdudaegan and, as a reference, in eight populations of its congener Lilium amabile, a temperate species that is distributed on lower hillsides in peripheral regions of the Baekdudaegan. L. cernuum harbored higher levels of genetic variation within populations than L. amabile (%P = 49.1 vs. 25.0, A = 1.71 vs. 1.34, and H e = 0.159 vs. 0.048). Genetic differentiation among populations was low for both species (F ST = 0.119 and 0.014 for L. cernuum and L. amabile, respectively). A series of historical and ecological factors may explain the contrasting levels of genetic diversity between L. cernuum and L. amabile: occurrence within the main ranges of the Baekdudaegan (enduring the glacial periods in macrorefugia) vs. low elevation peripheral areas (in microrefugia) and shade-tolerant vs. shade-intolerant. This study, as well as previous population genetics studies, strongly suggests that the Baekdudaegan merits high priority for conservation given its proposed role as glacial refugia for montane species. [Copyright &y& Elsevier]

ABSTRACT Macroinvertebrates' response to hydromorphological alterations and regulated flows along lowland rivers is still poorly known despite ecohydrology's fundamental role in river science. Along the Oglio River (Northern Italy), several water abstractions and dams break it into segments with varying hydraulic and morphological properties. Three types of a priori different environments were identified (dammed, downstream and free flowing sections), and macroinvertebrate communities were sampled from each zone. This study aimed (i) to investigate patterns of macroinvertebrate communities along a regulated lowland river by testing the a priori zones; (ii) to find macroinvertebrate taxa that served as indicators of the various hydrological conditions and (iii) to verify hydromorphological control over ecological macroinvertebrate traits resulting in different trait values in each identified zone. Macroinvertebrate community was characterized in a total of 63 stations by means of two quantitative approaches, each exploring a surface of 0.5 m2. The lowest richness values were found in dammed sites that tended toward lentic conditions. Ecnomidae (dammed zones), Limoniidae (downstream zones) and Heptageniidae (free flowing section) were identified as the best indicators of varying hydrological conditions. As suggested by the results of 4th Corner Method, environmental constraints define communities with different ecological traits. These results highlight hydromorphological control over macroinvertebrate community structure and reflect how regulated flows affect the Oglio River in terms of biodiversity, indicator taxa and ecological traits. The authors wish to stress the importance of considering the ecological effects of dams and impoundments on river systems in upstream areas as well as downstream. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An on-farm pollination experiment was conducted during the June–August and November–February blooming seasons of 2007 to 2008, in 30 small-scale coffee fields characterised by different habitat and vegetation types. The study was conducted in order to determine the best pollinator groups for coffee in Uganda and to collect relevant field information and determine the pollination efficiency of different bee species. Results indicate that across blooming seasons, coffee flowers were visited by 24–36 bee species.Hypotrigona gribodoiwas the most frequent flower visitor, comprising over 60% of 5941 bee-visits recorded. Foraging rate and pollination speed varied among bee species. Solitary bees foraged on more flowers than social bees, but they spent less time per flower visited. Solitary bees visited more coffee trees and fields, but deposited less pollen, whereas social bees visited less trees and coffee fields in the landscape, but deposited more pollen on flowers. Fruit set was of 87%, 64% and 0.9%, respectively, in hand-cross pollination, open pollination and controlled-pollination treatments. Fruit abortion due to self-pollination was insignificant in this study. There was variability in pollination efficiency of different bee species. Pollination efficiency varied more significantly with sociality than with other bee functional traits and was not significantly influenced by tongue length and bee body size. Single-flower visits by social and solitary bees resulted in 89.7% and 68.14% fruit set, respectively. The most efficient bee species wasMeliponula ferruginea(98.3%) followed byMeliponula nebulata(97.1%). Thus, very good pollinator species were wild social bees (mainly stingless bees) as opposed to honeybees and solitary bees that were previously reported to be the best pollinators of coffee in Panama and Indonesia. Morphological and anatomical characteristics of the bee pollen storage features may explain the difference in foraging behaviour activities and in pollination efficiency of social and solitary afrotropical bee species visiting lowland coffee in Uganda. In addition, pollination efficiency was influenced by land-use intensity, field management systems and habitat types found in the immediate surroundings of coffee fields, but not by coffee field size, coffee genotypes and mass blooming wild vegetation. It is recommended to farmers to adopt pollinator-friendly conservation and farming practices such as keeping an uncultivated portion (25%–30%) of their farms as pollinator reservoirs, protecting semi-natural habitats found in the vicinity of coffee fields, as well as promoting high on-farm tree cover to benefit a functionally diverse pollinator community. [ABSTRACT FROM PUBLISHER]

Studies to date have documented substantial variation among species in the degree to which phenology responds to temperature and shifts over time, but we have a limited understanding of the causes of such variation. Here, we use a spatially and temporally extensive data set (ca. 48 000 observations from across Canada) to evaluate the utility of museum collection records in detecting broad-scale phenology-temperature relationships and to test for systematic differences in the sensitivity of phenology to temperature (days °C−1) of Canadian butterfly species according to relevant ecological traits. We showed that the timing of flight season predictably responded to temperature both across space (variation in average temperature from site to site in Canada) and across time (variation from year to year within each individual site). This reveals that collection records, a vastly underexploited resource, can be applied to the quantification of broad-scale relationships between species' phenology and temperature. The timing of the flight season of earlier fliers and less mobile species was more sensitive to temperature than later fliers and more mobile species, demonstrating that ecological traits can account for some of the interspecific variation in species' phenological sensitivity to temperature. Finally, we found that phenological sensitivity to temperature differed across time and space implying that both dimensions of temperature will be needed to translate species' phenological sensitivity to temperature into accurate predictions of species' future phenological shifts. Given the widespread temperature sensitivity of flight season timing, we can expect long-term temporal shifts with increased warming [ca. 2.4 days °C−1 (0.18 SE)] for many if not most butterfly species. [ABSTRACT FROM AUTHOR]

Abstract: Paxillus involutus is a model species for ecological or physiological studies of ectomycorrhizal agaricomycetes. Three to six groups or species linked to it have been ecologically and morphologically distinguished. Phylogenetic studies have revealed the existence of four species in Europe: Paxillus ammoniavirescens, Paxillus obscurisporus, P. involutus, and a fourth as yet not described species. We studied 47 collections from 24 French and Italian locations, supplemented with GenBank data, in order to genetically and taxonomically delineate these species. Phylogenetic analyses of three nuclear DNA regions (rDNA internal transcribed spacer (ITS), tef1-α, and gpd) confirmed the four European species. Morphology, culture, and ecology features allowed us to delineate species boundaries and to describe the fourth species we named Paxillus cuprinus since it turns coppery with age. As there is no existing original herbarium specimen for P. involutus, one of our collections was chosen as the epitype. The low genetic diversity found in P. cuprinus correlates with stable morphological traits (basidiome colour, ovoid–amygdaliform spores with an apical constriction) and with ecological preferences (association with Betulaceae in open and temperate areas). In contrast, P. ammoniavirescens is characterized by a high genetic diversity and a high variation of its morphological and ecological features. [Copyright &y& Elsevier]

Background and Aims In habitat mosaics, plant populations face environmental heterogeneity over short geographical distances. Such steep environmental gradients can induce ecological divergence. Lowland rainforests of the Guiana Shield are characterized by sharp, short-distance environmental variations related to topography and soil characteristics (from waterlogged bottomlands on hydromorphic soils to well-drained terra firme on ferralitic soils). Continuous plant populations distributed along such gradients are an interesting system to study intrapopulation divergence at highly local scales. This study tested (1) whether conspecific populations growing in different habitats diverge at functional traits, and (2) whether they diverge in the same way as congeneric species having different habitat preferences. Methods Phenotypic differentiation was studied within continuous populations occupying different habitats for two congeneric, sympatric, and ecologically divergent tree species (Eperua falcata and E. grandiflora, Fabaceae). Over 3000 seeds collected from three habitats were germinated and grown in a common garden experiment, and 23 morphological, biomass, resource allocation and physiological traits were measured. Key Results In both species, seedling populations native of different habitats displayed phenotypic divergence for several traits (including seedling growth, biomass allocation, leaf chemistry, photosynthesis and carbon isotope composition). This may occur through heritable genetic variation or other maternally inherited effects. For a sub-set of traits, the intraspecific divergence associated with environmental variation coincided with interspecific divergence. Conclusions The results indicate that mother trees from different habitats transmit divergent trait values to their progeny, and suggest that local environmental variation selects for different trait optima even at a very local spatial scale. Traits for which differentiation within species follows the same pattern as differentiation between species indicate that the same ecological processes underlie intra- and interspecific variation. [ABSTRACT FROM AUTHOR]

Taxonomic sufficiency (TS) has been proposed for assessing community composition and environmental impacts as a way to balance the need to indicate the biology of the organisms present with time and effort needed for species identification. TS has been applied most often to marine and freshwater macroinvertebrates, but tests of its usefulness are lacking for other freshwater groups. We analyzed the effects of taxonomic resolution, functional groupings, and data transformation on multivariate community patterns in periphyton, macrophytes, macroinvertebrates, and fishes, and on the quantification of biodiversity and environmental gradients. The applicability of TS differed strongly among taxonomic groups, depending on the average taxonomic breadth of the species sets. Numerical data resolution had more pronounced effects on community patterns than taxonomic resolution. Richness was strongly affected by data aggregation, but diversity indices were statistically reliable up to order level. Taxonomic aggregation had no significant influence on ability to detect environmental gradients. Functional surrogates based on biological traits, such as feeding type, reproductive strategy, and trophic state, were strongly correlated (r = 0.64-0.85) with taxonomic community composition. However, environmental correlations were generally lower with data aggregated to functional traits rather than to species. TS was universally applicable within taxonomic groups for different habitats in one biogeographic region. Aggregation to family or order was suitable for quantifying biodiversity and environmental gradients, but multivariate community analyses required finer resolution in fishes and macrophytes than in periphyton and macroinvertebrates. Sampling effort in environmental-impact studies and monitoring programs would be better invested in quantitative data and number of spatial and temporal replicates than in taxonomic detail. [ABSTRACT FROM AUTHOR]

Aim An important, unresolved question in macroecology is to understand the immense inter-specific variation in geographic range sizes. While species traits such as fecundity or body size are thought to affect range sizes, a general understanding on how multiple traits jointly influence them is missing. Here, we test the influence of a multitude of species traits on global range sizes of European passerine birds in order to better understand possible mechanisms behind macroecological relationships. Location Global. Methods We evaluated the effect of life-history traits (fecundity, dispersal ability), ecological traits (habitat niche, diet niche, migratory behaviour, migratory flexibility) and a morphological trait (body size) on the global range sizes of 165 European passerines. We identified hypotheses from the literature relating traits to range size and used path analysis to test them. Results Fecundity, dispersal ability and habitat niche breadth had a direct positive effect on range size. Diet niche position had a direct negative effect on range size. Habitat niche breadth also had an indirect positive effect via higher fecundity. Migratory behaviour had an indirect positive effect via better dispersal ability. Body size had a strong positive direct effect which was reduced by negative indirect effects via several other traits. Main conclusions Geographic range sizes of European passerines were influenced by life-history traits (fecundity and dispersal ability), ecological traits (habitat niche breadth, diet niche position and migratory behaviour) and by body size. Traits influenced range size both directly and indirectly. Body size effects were particularly complex, with positive and negative effects acting over different pathways. We show that it is necessary to disentangle the direct and indirect influence of multiple traits on range size to better elucidate the mechanisms that generate macroecological relationships. [ABSTRACT FROM AUTHOR]

Tree communities of secondary deciduous oak forests were surveyed in 13 forests (two in residential and 11 in rural areas) in the warm temperate Hokuriku District of Japan to understand the effects of fragmentation, location (residential or rural), and logging history. The rural forest logged most recently, where diameter at breast height was smallest, had a distinct canopy tree (>12 m) community due to an increase of trees from wind-dispersed seeds. The rural forest with gaps and the two residential forests also had different canopy tree communities from the other rural forests. In contrast, the tree community in the shrub layer (≤6 m) was not influenced by logging history and the existence of gaps but by location only. This was caused by an increase in evergreen trees (consequently causing poor light conditions on the forest floor) and a decrease in trees from wind-dispersed seeds in the residential forests. Among the rural forest patches, no negative effects of forest size and isolation on density of tree individuals were detected for any seed dispersal mode. This may be because many forest patches were arranged at distances of 10-50 m from neighboring patches in rural areas, which enables tree species with low dispersal ability to disperse their seeds to neighboring forests. However, as found in the residential forests, long-term abandonment and extensive fragmentation may gradually reduce tree diversity through loss of tree species with shade intolerance and low seed dispersal ability. [ABSTRACT FROM AUTHOR]

Longitudinal size segregation and reproductive aspects of Mimagoniates microlepis were studied along the catchment of the Piraquara River, a tributary of the Iguaçu River. Monthly fish sampling were completed at four sites along a longitudinal gradient. In addition, we summarized and compared key species-ecological traits of three different populations of this species. Data from the two additional populations were obtained from the literature. Our findings concerning population structure and reproduction of this species demonstrate that ontogenetic migration occurs within this population. During flash floods small individuals (C1) are carried to downstream habitats (P1). As they grow, we assume that their swimming capacity tends to increase and they are able to explore upstream habitats. This ontogenetic migration dynamic is a common and underexplored pattern for small stream fish in the Neotropics, and it helps to ensure, as a consequence, the long term persistence of the population along the entire hydrographic basin. Therefore, the alteration of only one portion of the river can compromise the entire migration process and consequently the entire population. In addition, the present study is the only source of ecological information for this population from before the recent construction of the Piraquara II dam. This reinforces the urgent need for conservation strategies for this population of M. microlepis and other similar populations or species. [ABSTRACT FROM AUTHOR]

We compared allozyme variation in the two arctic-alpine plants Diapensia lapponica var. obovata and Empetrum nigrum var. japonicum between Sakhalin Island in Russian Far East, within their range core, and the Korean island of Jeju, their world's southernmost distribution. For D. lapponica var. obovata, Sakhalin populations harbored moderate levels of within-population genetic variation and low among-population divergence, whereas extremely low levels of within-population genetic diversity and high among-population differentiation were found in Jeju Island populations. In contrast, we found moderate levels of within-population variation and low among-population differentiation in E. nigrum var. japonicum in both northern populations (those of Sakhalin and an additional population from northern Japan) and Jeju Island populations. Under a similar scenario of immigration history of arctic-alpine plants on Jeju Island during the glacial periods of the Pleistocene and local persistence through glacial/interglacial cycles, the contrasting genetic structure between D. lapponica var. obovata and E. nigrum var. japonicum is mainly attributable to their different life-history, ecological, and demographic traits: (1) hermaphroditic versus monoecious, dioecious or polygamous, (2) seeds with no adaptations for long-distance dispersal versus berry-like drupes dispersed by animals and birds, and (3) a very small patch near the peak of Mt. Halla with a few hundred individuals versus a relatively continuous distribution around the peak of Mt. Halla with numerous individuals. From a conservation perspective, in situ and ex situ conservation measures should be strengthened for D. lapponica var. obovata on Jeju Island given their extreme rarity there. [ABSTRACT FROM AUTHOR]

In Europe and North America, there is growing concern that biodiversity declines associated with agricultural intensification will adversely impact the functioning and sustainability of agricultural ecosystems. Enhancing habitat heterogeneity in agricultural landscapes promotes biodiversity and, whilst erecting fences adjacent to watercourses is widely advocated as a means of mitigating diffuse pollution, associated biodiversity benefits have been largely overlooked., A range of riparian margins and their adjacent grassland fields were investigated to determine the effects of riparian management on the diversity and functional structure of carabid assemblages. Carabid assemblages of fields and open margins (i.e. unfenced watercourses) were more diverse and species rich than those of fenced margins., The functional structure of carabid assemblages in fenced margins differed from grassland fields and open margins. This disparity was greater in wide margins (i.e. fences erected over 5·4 m from watercourses) than narrow margins (i.e. fences erected within 2·6 m of watercourses). Wide margins had the highest relative proportions of carabids which had pushing body forms, were flightless, very small in size and Collembola specialists. During early summer, wide margins also had the highest proportion of carabids that overwinter as adults., The taxonomic and functional structure of carabid assemblages was more sensitive for detecting impacts of agricultural management than measurements of diversity. It is likely that this also applies to other taxa, thus emphasising the need to consider a wide range of assemblage attributes when investigating agricultural impacts on biodiversity., Synthesis and applications. Fenced riparian margins, particularly those over 5·4 m wide, harbour carabids with poor dispersal ability which are vulnerable to habitat fragmentation. While lack of management benefits sedentary species, a wider range of taxa (e.g. pollinators, foraging birds and flowering plants) are enhanced by management to obtain a more open vegetation structure (e.g. restricted grazing or mowing). It is important that management practices are implemented at a sufficiently fine spatial scale to allow recolonisation of species with restricted dispersal from adjacent undisturbed habitats. Wide riparian margins have the potential to enhance taxonomic and functional diversity at the landscape scale. Management actions must, however, be carefully balanced to ensure that they promote a wide range of taxa without unduly interfering with the margin's ability to mitigate diffuse pollution. [ABSTRACT FROM AUTHOR]

1. Coleoptera species show considerable diversity in life histories and ecological strategies, which makes possible their wide distribution in freshwater habitats, including highly stressed ones such as saline or temporary waterbodies. Explaining how particular combinations of traits allow species to occupy distinctive habitats is a central question in ecology. 2. A total of 212 sites, sampled over a wide range of inland aquatic habitats in the south-eastern Iberian Peninsula, yielded 272 species belonging to 68 genera and 11 families. The affinities of genera for 11 biological and 11 ecological traits, gathered from literature and the authors' own expertise, were used to assess the degree of congruence between taxonomic, biological and ecological traits. 3. Taxonomic richness was significantly related to the number of both biological and ecological trait categories, with the richest families also showing the highest functional and ecological diversity. A fuzzy correspondence analysis performed on the abundance-weighed array of biological traits separated genera according to categories of diet, feeding habits, respiration, reproduction and locomotion. A similar analysis of ecological traits revealed that preferences related to longitudinal distribution (headwater to mouth), local habitat and current velocity best discriminated genera. At the family level, there was a distinctive functional grouping of genera based on biological traits. Only Elmidae showed noticeable homogeneity across genera for both biological and ecological traits. 4. Co-inertia analysis demonstrated a significant match between biological and ecological traits ( Rv-correlation = 0.35, P < 0.001). Elmidae genera displayed the highest concordance, whereas Hydraenidae demonstrated the lowest. 5. These results indicate that the predominance of habitat filtering processes in headwater streams yields biological trait conservatism (as shown by Elmidae genera), as well as trait convergence for some specific traits (for instance, respiration) among certain Dytiscidae genera and other typical rheophilic taxa, whereas other biotic factors, such as competition among species, appear more prominent in less stressed habitats. Further knowledge of traits, especially regarding physiological capabilities, is needed to better understand water beetle life history strategies. [ABSTRACT FROM AUTHOR]

The occurrence of the non-indigenous species Limnoperna securis belonging to Mytilidae family is recorded for the first time in the Bay of Biscay. Numerous individuals were collected in intertidal and shallow waters in the inner part of Nervión estuary (Bizkaia, Basque Country, SE Bay of Biscay). In the present paper, notes about the history of this small brown mussel invasion, vectors of introduction and dispersal, as well as consequences of invasion are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Sediments are considered as a sink for metals, and the assessment of metal bioavailability for benthic organisms represents a great challenge. Diffusive Gradient in Thin films (DGT), developed to measure labile metals in aquatic media, have more recently been applied to sediment. Nevertheless, few studies have determined the relation between measurements from DGT and bioaccumulation in different benthic organisms. The aim of our work was to determine if labile metal measured by DGT in sediment is representative of bioavailable metal for benthic organisms. We focused our work on Cd and chose to use the diversity of ecological traits from different organisms to better understand the measurement given by DGT. We exposed simultaneously DGT and 3 macroinvertebrates species (the chironomid, Chironomus riparius; the amphipod, Gammarus fossarum; the mudsnail, Potamopyrgus antipodarum) to a natural sediment Cd-spiked at environmental relevant concentrations. The nature of sediment-bound Cd was also determined by means of sequential extractions in order to better interpret DGT measurements. Cadmium concentrations were determined in DGT and in the 3 organisms after one week of exposure. Results provided by DGT indicated that Cd was poorly released from particulate phase to pore water, suggesting that Cd measured by DGT was representative of the pore water labile fraction. Sequential extractions showed that the percentage of Cd bound to carbonate fraction increased simultaneously with Cd-spiking level; hence, this Cd fraction was poorly reactive to supply DGT demand. Cadmium accumulation rates were similar between DGT measurements and P. antipodarum, suggesting that labile Cd in pore waters was representative of bioavailable Cd for this species. Cadmium accumulation rates in C. riparius were higher than in DGT, demonstrating that C. riparius can mobilize Cd bound to carbonate phase. G. fossarum showed the lowest Cd accumulation rates, suggesting that they were mainly exposed to Cd from overlaying waters. [Copyright &y& Elsevier]

I review species concepts, the taxonomy of phlebotomine sand flies, and some transmission cycles of leishmaniasis in order to illustrate the difficulties of classifying these vectors in a way that will be ideal both for medical parasitologists and sand fly specialists. Choices will have to be made between different classifications, either maintaining a practical one containing few vectorial genera (mostly Phlebotomus for the Old World and Lutzomyia for the Neotropics) or changing the generic names of many vectors so that the classification represents an evolutionary hypothesis. However, sand flies also transmit arboviruses and members of other sand fly genera bite humans, and so vectorial status alone might not provide the criteria for recognizing only a few genera. Vectorial roles are often determined by species-level co-evolution of susceptibility to Leishmania species, with selection being initiated and maintained by ecological contacts. There is only imperfect cocladogenesis of genus-level groups or subgeneric complexes of sand flies and Leishmania species. Natural hybridization between sand fly species has been recorded in several species complexes, and this highlights the need to focus on gene flow and the distribution of phenotypes of biomedical importance, not on taxa. [ABSTRACT FROM AUTHOR]

Crayfishes are both a highly imperiled invertebrate group as well as one that has produced many invasive species, which have negatively affected freshwater ecosystems throughout the world. We performed a trait analysis for 77 crayfishes from the southeastern United States in an attempt to understand which biological and ecological traits make these species prone to imperilment or invasion, and to predict which species may face extinction or become invasive in the future. We evaluated biological and ecological traits with principal coordinate analysis and classification trees. Invasive and imperiled crayfishes occupied different positions in multivariate trait space, although crayfishes invasive at different scales (extraregional vs. extralimital) were also distinct. Extraregional crayfishes (large, high fecundity, habitat generalists) were most distinct from imperiled crayfishes (small, low fecundity, habitat specialists), thus supporting the “two sides of the same coin” hypothesis. Correct classification rates for assignment of crayfishes as invasive or imperiled were high (70–80%), even when excluding the highly predictive but potentially confounding trait of range size (75–90%). We identified a number of species that, although not currently listed as imperiled or found outside their native range, possess many of the life-history and ecological traits characteristic of currently invasive or imperiled taxa. Such species exhibit a high latent risk of extinction or invasion and consequently should be the focus of proactive conservation or management strategies. Our results illustrate the utility of trait-based approaches for taxonomic groups such as invertebrates, for which detailed species-specific data are rare and conservation resources are chronically limited. [ABSTRACT FROM AUTHOR]