Search

Heterospecific sociability could enhance invasion success in social species since social non‐natives usually belong to small founding populations during the early stages of invasion. The twospot livebearer (Pseudoxiphophorus bimaculatus) is native to Central America and southern Mexico and is recently recognised as invasive in the Mexican Central Plateau, where it poses a threat to native species. Here, we evaluated twospot livebearer sociability towards either a conspecific pair or a shoal of four fish with one of four possible compositions, all conspecifics or two conspecifics combined with either two guppies, two porthole livebearers or two twoline skiffias. In a second experiment, foraging time, latency to feed, first fish to begin foraging and aggressive interactions were recorded under the same social conditions used in the sociability experiment, with body size included as a covariate in both experiments. All focal twospot livebearers spent significantly more time with the given shoals rather than with the available space in the aquarium. They showed a higher tendency to associate with small shoals of conspecifics than with pairs. Larger twospot livebearers associated more, regardless of the social condition. Twospot livebearer fed more with porthole livebearers, less with guppies and similarly with twoline skiffias. Latency to forage did not vary significantly between social conditions. Twospot livebearers were involved in more aggressive interactions when with guppies or porthole livebearers than when with native twoline skiffias or conspecifics. Twospot livebearers could gain benefits from associating with natives and conspecifics, but not with other invasive poeciliids. Heterospecific shoaling behaviour with natives may enhance invasion success during early stages when conspecifics are scarce while associating with other invasive poeciliids could lead to increased competition. Further research is needed on heterospecific interactions of non‐natives to better understand their behavioural role in invasion likelihood. [ABSTRACT FROM AUTHOR]

Native parasitoids are potential tools for the biological control of invasive exotic pests, such as the frugivorous flies spotted‐wing drosophila, Drosophila suzukii Matsumura, and African fig fly, Zaprionus indianus Gupta (both Diptera: Drosophilidae). Following biological invasions, the establishment of exotic species may be restricted, among other things, by their susceptibility to native or established natural enemies. The Neotropical‐native pupal endoparasitoid Trichopria anastrephae Costa Lima (Hymenoptera: Diapriidae), although primarily associated with hosts of the genus Anastrepha (Tephritidae), has also been described to attack Drosophilidae. There are few studies on the interaction between parasitoids native to Argentina and D. suzukii and/or Z. indianus. The present work evaluates the parasitism of T. anastrephae on both species of drosophilids under controlled conditions. Ten larvae (L3) of each host species were exposed separately to a couple of adult T. anastrephae for 72 h (n = 10). For both control and parasitoid treatment, 10 larvae (L3) of D. suzukii and Z. indianus were placed in 10 flasks (repetition) at the L3 stage. Host emergence, the infestation degree index (DI), and the parasitism success rate (SP) were calculated. Drosophila suzukii and Z. indianus emergence differed significantly in controlled conditions being 41% higher for Z. indianus than for D. suzukii. The DI was 100% in D. suzukii and 38% in Z. indianus, and the SP was 48% both in D. suzukii and in Z. indianus. These findings indicate that the native parasitoid T. anastrephae has a high potential as a biocontrol strategy against D. suzukii. In addition, the efficiency of T. anastrephae against Z. indianus, an invasive frugivorous widely spread in the Neotropical region, was evaluated for the first time. [ABSTRACT FROM AUTHOR]

Aim: Metabolic rate is a widely studied physiological species trait related to energetics, climate, and geographical distributions. Hypotheses have been proposed to explain variation in metabolic rate, but evidence has been mixed due to the limited sampling scope of intraspecific studies. Successful biological invasions offer a unique opportunity to examine the development of intraspecific physiological variation and how it relates to climate, invasive spread and species range limits. The aim of this study was to determine if metabolic rate variation across the spongy moth invasive range was consistent with a pattern of adaptation to local climate. Location: Northeastern United States of America. Taxon: Lymantria dispar dispar L. (Lepidoptera: Erebidae). Methods: Larvae were sourced from 14 populations across the invasion front and interior of the current L. d. dispar invasive range and were reared at a constant temperature. Routine metabolic rates (RMR) of larvae were assayed at three ecologically relevant temperatures. These data were analysed to determine if there were differences in RMR and temperature sensitivity of RMR among populations. Population‐level variation in RMR was then analysed as a function of local climate and geographical position to test for patterns consistent with local adaptation. Results: Larval RMR showed significant variation among populations across all assay temperatures, but there was no difference in temperature sensitivity (i.e. slope). This variation followed a positive latitudinal cline with RMR increasing from the southern range to the north. This cline also showed a significant relationship with local climate variables. Main Conclusions: Larval metabolic rate variation was consistent with a pattern of adaptation by L. d. dispar to divergent climates across its invasive range. These results indicated that thermal adaptation of whole‐organism physiology may play a key role in promoting species spread and expansion for biological invasions like L. d. dispar. [ABSTRACT FROM AUTHOR]

There is a long history of humans either intentionally or accidentally moving plant species to areas outside of their native ranges. In novel environments, populations of many of these plant species exhibit explosive population growth and spread, in part due to the absence of coevolved enemies such as herbivorous insects. However, over time such enemies can 'catch up' with their host and re‐establish host–herbivore relationships. Though this phenomenon has been documented in several systems, little evidence exists on how this re‐assembly of enemies results in increased levels of herbivory. In this study we focus on the case of black locust Robinia pseudoacacia, a sparsely populated tree species when growing on undisturbed sites in its limited native range in the eastern USA but a highly invasive species, especially in disturbed environments, in most temperate world regions. We recorded folivore damage on invasive populations in five continents, including both native and invaded portions of North America. Here, we investigated 1) how total foliage damage and damage caused by different groups of folivores differs among regions; 2) how seasonal development of folivore damage differs among regions; 3) how folivory varies with distance from the native range within North America; and 4) how the number of recorded specialist folivores correlates with the amount of folivory. We observed strong differences among regions in the amount and type of folivore damage, with the native range experiencing the highest damage, especially that caused by the native chrysomelid beetle Odontota dorsalis, which is limited to the native and invaded North American range of R. pseudoacacia. Among world regions, total folivory is negatively associated with the distance from the native range and positively associated with the number of established R. pseudoacacia specialist folivore species, supporting the hypothesis that global patterns of herbivore invasions are associated with diminished enemy release. [ABSTRACT FROM AUTHOR]

Xylosandrus crassiusculus is an invasive ambrosia beetle comprising two differentiated genetic lineages, named cluster 1 and cluster 2. These lineages invaded different parts of the world at different periods of time. We tested whether they exhibited different climatic niches using Schoener's D and Hellinger's I indices and modeled their current potential geographical ranges using the Maxent algorithm. The resulting models were projected according to future and recent past climate datasets for Europe and the Mediterranean region. The future projections were performed for the periods 2041–2070 and 2071–2100 using 3 SSPs and 5 GCMs. The genetic lineages exhibited different climate niches. Parts of Europe, the Americas, Sub-Saharan Africa, Asia, and Oceania were evaluated as suitable for cluster 1. Parts of Europe, South America, Central and South Africa, Asia, and Oceania were considered as suitable for cluster 2. Models projection under future climate scenarios indicated a decrease in climate suitability in Southern Europe and an increase in North Eastern Europe in 2071–2100. Most of Southern and Western Europe was evaluated as already suitable for both clusters in the early twentieth century. Our results show that large climatically suitable regions still remain uncolonized and that climate change will affect the geographical distribution of climatically suitable areas. Climate conditions in Europe were favorable in the twentieth century, suggesting that the recent colonization of Europe is rather due to an increase in propagule pressure via international trade than to recent environmental changes. [ABSTRACT FROM AUTHOR]

Rapid evolution in colonising populations can alter our ability to predict future range expansions. Recent theory suggests that the dynamics of replicate range expansions are less variable, and hence more predictable, with increased selection at the expanding range front. Here, we test whether selection from environmental gradients across space produces more consistent range expansion speeds, using the experimental evolution of replicate duckweed populations colonising landscapes with and without a temperature gradient. We found that the range expansion across a temperature gradient was slower on average, with range‐front populations displaying higher population densities, and genetic signatures and trait changes consistent with directional selection. Despite this, we found that with a spatial gradient range expansion speed became more variable and less consistent among replicates over time. Our results therefore challenge current theory, highlighting that chance can still shape the genetic response to selection to influence our ability to predict range expansion speeds. [ABSTRACT FROM AUTHOR]

Community coalescence is defined as the mixing of intact ecological communities and their environments. It is a common phenomenon in microbial systems with implications for biodiversity, ecosystem functioning, and human health. Research on community coalescence has recently surged, spanning various fields from clinical settings to natural and engineered microbial (eco)systems. We provide a synthesis that integrates an existing framework for invasion biology with commonalities and idiosyncrasies of community coalescence. Embracing the complexity of community coalescence in microbial systems and advancing the study of the ecological processes determining microbial engraftment is of paramount importance to better inform and predict the outcomes of microbiome manipulation across divergent systems. Community coalescence is defined as the mixing of intact ecological communities. From river confluences to fecal microbiota transplantation, community coalescence constitutes a common ecological occurrence affecting natural and engineered microbial systems. In this opinion article, we propose an integrative framework for microbial community coalescence to guide advances in our understanding of this important – yet underexplored – ecological phenomenon. We start by aligning community coalescence with the unified framework of biological invasion and enumerate commonalities and idiosyncrasies between these two analogous processes. Then, we discuss how organismal interactions and cohesive establishment affect coalescence outcomes with direct implications for community functioning. Last, we propose the use of ecological null modeling to study the interplay of ecological processes structuring community reassembly following coalescence. [ABSTRACT FROM AUTHOR]

Identifying areas at high risk of invasion is considered an important step for prioritization of phytosanitary measures to prevent biological invasions. Because climate change is likely to affect species' habitat suitability, ideally this should be considered in invasion risk assessments.We evaluated whether climate change affects habitat suitability and invasion risk of eight potentially invasive Eucalyptus pests in Brazil: Eucalyptolyma maideni, Mnesampela privata, Ophelimus maskelli, Orgyia postica, Paropsis atomaria, Paropsisterna beata, Paropsisterna cloelia and Trachymela sloanei.The shifts in the distribution range varied depending on the species, year and climate change scenario. While a decrease in the distribution range was predicted for four species, an increase was predicted for two species. Moreover, a decrease and/or increase in distribution depending on the climate change scenario was predicted for two species.Increases in invasion risk were predicted in major Eucalyptus‐producing areas near international airports and high cargo volume seaports.Our study provides an important contribution to knowledge on the effects of climate change on the distribution of eight potentially invasive Eucalyptus pests and reinforces the need to consider the changes in species' habitat suitability in invasion risk assessments. [ABSTRACT FROM AUTHOR]

Biological invasions are a major environmental challenge today. Interactions between invasive and native species can significantly shape community structures, influencing coexistence, diversity and functional composition of species. The subtropical Atlantic Forest in southern Brazil, a recognized biodiversity hotspot, provides a unique setting to study these interactions, given its vulnerability to alien tree invasions.Our study sought to elucidate the impacts of such invasions on this fragile ecosystem by addressing key questions: (1) How are tree community diversity patterns affected by the abundance of invading alien tree species? (2) What are the patterns of coexistence between native and alien invasive trees? (3) Is the functional composition of the forests altered by the abundance of invasive trees?To address these questions, we compiled data on the abundance and functional traits of native and invasive trees. We determined the diversity patterns and functional composition of plots with different degrees of invasion. These data were analysed using generalized linear mixed models, principal component analysis and a coexistence index.In plots with a higher abundance of invasive trees, there was a significant decrease in the taxonomic and functional richness (FRic) of native species. Furthermore, we observed that invasive alien trees coexisted with native species, and as the abundance of invasive trees increased, the native community‐weighted mean of the leaf area (LA) and specific leaf area (SLA) decreased.In conclusion, within the subtropical Atlantic Forest areas of southern Brazil, our findings highlight that the abundance of invasive trees adversely affects the taxonomic and FRic of native species. Furthermore, while invasive alien trees were found to coexist with native species, increased invasive abundance corresponded to a reduction in the LA and the SLA of the native community. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Human activities are accelerating rates of biological invasions and climate-driven range expansions globally, yet we understand little of how genomic processes facilitate the invasion process. Although most of the literature has focused on underlying phenotypic correlates of invasiveness, advances in genomic technologies are showing a strong link between genomic variation and invasion success. Here, we consider the ability of genomic tools and technologies to (i) inform mechanistic understanding of biological invasions and (ii) solve real-world issues in predicting and managing biological invasions. For both, we examine the current state of the field and discuss how genomics can be leveraged in the future. In addition, we make recommendations pertinent to broader research issues, such as data sovereignty, metadata standards, collaboration, and science communication best practices that will require concerted efforts from the global invasion genomics community. [ABSTRACT FROM AUTHOR]

Biological invasions have major impacts on a variety of ecosystems and threaten native biodiversity. Earthworms have been absent from northern parts of North America since the last ice age, but non‐native earthworms were recently introduced there and are now being spread by human activities. While past work has shown that plant communities in earthworm‐invaded areas change towards a lower diversity mainly dominated by grasses, the underlying mechanisms related to changes in the biotic interactions of the plants are not well understood. Here, we used a trait‐based approach to study the effect of earthworms on interspecific plant competition and aboveground herbivory. We conducted a microcosm experiment in a growth chamber with a full‐factorial design using three plant species native to northern North American deciduous forests, Poa palustris (grass), Symphyotrichum laeve (herb) and Vicia americana (legume), either growing in monoculture or in a mixture of three. These plant community treatments were crossed with earthworm (presence or absence) and herbivore (presence or absence) treatments. Eight out of the fourteen above‐ and belowground plant functional traits studied were significantly affected by earthworms, either by a general effect or in interaction with plant species identity, plant diversity level and/or herbivore presence. Earthworms increased the aboveground productivity and the number of inflorescences of the grass P. palustris. Further, earthworms and herbivores together affected root tissue density of P. palustris and the specific leaf area of V. americana. In this study, earthworm presence gave a competitive advantage to the grass species P. palustris by inducing changes in plant functional traits. Our results suggest that invasive earthworms can alter competitive and multitrophic interactions of plants, shedding light on some of the mechanisms behind invasive earthworm‐induced plant community changes in northern North America forests. [ABSTRACT FROM AUTHOR]

Rates of biological invasion are increasing globally, with associated negative effects on native biodiversity and ecosystem services. Among other genetic processes, hybridisation can facilitate invasion by producing new combinations of genetic variation that increase adaptive potential and associated population fitness. Yet the role of hybridisation (and resulting gene flow) in biological invasion in invertebrate species is under‐studied. Calliphora hilli and Calliphora stygia are blowflies proposed to have invaded New Zealand separately from Australia between 1779 and 1841, and are now widespread throughout the country. Here, we analysed genome‐wide single nucleotide polymorphisms (SNPs), generating genotyping‐by‐sequencing data for 154 individuals collected from 24 populations across New Zealand and Australia to assess the extent of gene flow and hybridisation occurring within and between these blowflies and to better understand their overall population structure. We found that New Zealand populations of both species had weak genetic structure, suggesting high gene flow and an absence of dispersal limitations across the country. We also found evidence that interspecific hybridisation is occurring in the wild between C. hilli and C. stygia in both the native and invasive ranges, and that intraspecific admixture is occurring among populations at appreciable rates. Collectively, these findings provide new insights into the population structure of these two invasive invertebrates and highlight the potential importance of hybridisation and gene flow in biological invasion. [ABSTRACT FROM AUTHOR]

Understanding the determinants of the range expansion of invasive alien species is crucial for developing effective prevention and control strategies. Nevertheless, we still lack a global picture of the potential factors influencing the invaded range expansion across taxonomic groups, especially for the world's worst invaders with high ecological and economic impacts. Here, by extensively collecting data on 363 distributional ranges of 19 of world's worst invasive terrestrial vertebrates across 135 invaded administrative jurisdictions, we observed remarkable variations in the range expansion across species and taxonomic groups. After controlling for taxonomic and geographic pseudoreplicates, model averaging analyses based on generalized additive mixed‐effect models showed that species in invaded regions having climates more similar to those of their native ranges tended to undergo a larger range expansion. In addition, as proxies of propagule pressure and human‐assisted transportation, the number of introduction events and the road network density were also important predictors facilitating the range expansion. Further variance partitioning analyses validated the predominant role of climate match in explaining the range expansion. Our study demonstrated that regions with similar climates to their native ranges could still be prioritized to prevent the spread of invasive species under the sustained global change. [ABSTRACT FROM AUTHOR]

The enemy release hypothesis (ERH) is the best‐known hypothesis explaining high performance (e.g. rapid population growth) of exotic species. However, the current framing of the ERH does not explicitly link evidence of enemy release with exotic performance. This leads to uncertainty regarding the role of enemy release in biological invasions. Here, we demonstrate that the effect of enemy release on exotic performance is the product of three factors: enemy impact, enemy diversity, and host adaptation. These factors are modulated by seven contexts: time since introduction, resource availability, phylogenetic relatedness of exotic and native species, host–enemy asynchronicity, number of introduction events, type of enemy, and strength of growth–defence trade‐offs. ERH‐focused studies frequently test different factors under different contexts. This can lead to inconsistent findings, which typifies current evidence for the ERH. For example, over 80% of meta‐analyses fail to consider ecological contexts which can alter study findings; we demonstrate this by re‐analysing a recent ERH synthesis. Structuring the ERH around factors and contexts promotes generalisable predictions about when and where exotic species may benefit from enemy release, empowering effective management. Our mechanistic factor–context framework clearly lays out the evidence required to support the ERH, unifies many enemy‐related invasion hypotheses, and enhances predictive capacity. [ABSTRACT FROM AUTHOR]

Invasive alien species are considered some of the most important causes of biodiversity loss on a global scale. This explains why interest in their research has been steadily rising in recent years. A review of botanical literature for the Bulgarian flora shows that after 2000 more than 100 alien species of vascular plants have been reported for the first time for the Bulgarian flora. The report presents an analysis of these species in terms of their origin, pathways of introduction and further spread, affected floristic regions, etc. [ABSTRACT FROM AUTHOR]

Biological invasions have increased significantly with the tremendous growth of international trade and transport. Hematophagous arthropods can be vectors of infectious and potentially lethal pathogens and parasites, thus constituting a growing threat to humans—especially when associated with biological invasions. Today, several major vector-borne diseases, currently described as emerging or re-emerging, are expanding in a world dominated by climate change, land-use change and intensive transportation of humans and goods. In this review, we retrace the historical trajectory of these invasions to better understand their ecological, physiological and genetic drivers and their impacts on ecosystems and human health. We also discuss arthropod management strategies to mitigate future risks by harnessing ecology, public health, economics and social-ethnological considerations. Trade and transport of goods and materials, including vertebrate introductions and worn tires, have historically been important introduction pathways for the most prominent invasive hematophagous arthropods, but sources and pathways are likely to diversify with future globalization. Burgeoning urbanization, climate change and the urban heat island effect are likely to interact to favor invasive hematophagous arthropods and the diseases they can vector. To mitigate future invasions of hematophagous arthropods and novel disease outbreaks, stronger preventative monitoring and transboundary surveillance measures are urgently required. Proactive approaches, such as the use of monitoring and increased engagement in citizen science, would reduce epidemiological and ecological risks and could save millions of lives and billions of dollars spent on arthropod control and disease management. Last, our capacities to manage invasive hematophagous arthropods in a sustainable way for worldwide ecosystems can be improved by promoting interactions among experts of the health sector, stakeholders in environmental issues and policymakers (e.g. the One Health approach) while considering wider social perceptions. [ABSTRACT FROM AUTHOR]

Aim: Analysing the spatio‐temporal patterns and dynamics of non‐native species is essential to understanding the mechanisms underlying successful invasions and developing effective management strategies. Yet, such analyses generally neglect the influence of receiving ecosystem types and non‐native species sources (i.e. alien species, non‐natives originating outside the concerned region; translocated species, non‐natives introduced to locations outside their historical range within the concerned region). Location: Yunnan, China. Methods: We analysed long‐term (1950–2022) spatio‐temporal patterns and potential underlying dynamics of non‐native fishes in a biodiversity hotspot (Yunnan, China), paying special attention to waterbody types receiving non‐native species and comparing alien and translocated species. We did this through compiling a highly comprehensive occurrence dataset of native and non‐native fishes. Results: We recorded 783 native species and 94 non‐native species (49 alien species and 45 translocated species), which mainly belonged to the order Cypriniformes (52 species) and were introduced via purposes for advancing aquaculture. Most frequently encountered non‐native species were either intentionally introduced aquaculture species or small‐bodied fish unintentionally introduced via aquaculture activities. The richness and spatial ranges of non‐native fishes increased consistently since the 1950s and demonstrated a pronounced change after the 2000s, with densely populated areas and the middle to lower reaches of large rivers being more profoundly affected. The number of records of translocated species exceeded the number of records of alien species after the 2000s. Lakes and reservoirs are hotspots for both alien and translocated species introductions, and watersheds with large areas in Yunnan (e.g. the Jinsha‐Yangtze and Lancang‐Mekong basins) contained more non‐native fish. Main Conclusions: Our study highlights the need to consider invasion sensitivities of receiving ecosystems and pay special attention to intra‐regional species translocations when developing prevention and management strategies against invasions of alien species, particularly in important biodiversity hotspots around the world. [ABSTRACT FROM AUTHOR]

The increase in global trade and traffic networks contributes to the introduction and spread of invasive alien species, posing a threat to biodiversity. EU Regulation 1143/2014 addresses the prevention and management of invasive alien species and requires an action plan on the priority pathways of unintentional introduction and spread of invasive alien species by each member state. To this end, the first German action plan was developed for the German government in cooperation with relevant Ministries and authorities, scientists, administrative experts, stakeholder working groups and political as well as public deliberation processes. As a result, 14 priority pathways of unintentional introduction, escape or release and spread were identified, resulting in 24 targeted measures. Nineteen sectors will be involved in the implementation of these measures. Here we describe the development process and outcome of Germany's first action plan. By this, we aim making the process public and transparent, which can facilitate a revision of the action plan required at least every six years, and trigger broader European as well as national cooperation in the future. [ABSTRACT FROM AUTHOR]

Alternative splicing (AS), a pivotal biological process contributing to phenotypic plasticity, creates a bridge linking genotypes with phenotypes. Despite its importance, the AS mechanisms underlying environmental response and adaptation have not been well studied, and more importantly, the cis- and trans-acting factors influencing AS variation remain unclear. Using the model invasive congeneric ascidians, Ciona robusta, and Ciona savignyi, we compared their AS responses to environmental changes and explored the potential determinants. Our findings unveiled swift and dynamic AS changes in response to environmental challenges, and differentially alternative spliced genes (DASGs) were functionally enriched in transmembrane transport processes. Interestingly, both the prevalence and level of AS in C. robusta were lower than those observed in C. savignyi. Furthermore, these two indices were higher under temperature stresses compared to salinity stresses in C. savignyi. All the observed patterns underscore the species-specific and environmental context-dependent AS responses to environmental challenges. The dissimilarities in genomic structure and exon/intron size distributions between these two species likely contributed to the observed AS variation. Moreover, we identified a total of 11 and 9 serine/arginine-rich splicing factors (SRSFs) with conserved domains and gene structures in the genomes of C. robusta and C. savignyi, respectively. Intriguingly, our analysis revealed that all detected SRSFs did not exhibit prevalent AS regulations. Instead, we observed AS control over a set of genes related to splicing factors and spliceosome components. Altogether, our results elucidate species-specific and environmental challenge-dependent AS response patterns in closely related invasive ascidians. The identified splicing factors and spliceosome components under AS control offer promising candidates for further investigations into AS-mediated rapid responses to environmental challenges complementary to SRSFs. [ABSTRACT FROM AUTHOR]

Today biological invasion is one of the most dangerous threats to biodiversity and there are only few tools to monitor and control. This study structure and tested the potential of niche modeling procedures from data of occurrence of Hovenia dulcis Thunberg, and Tithonia diversifolia (Hemsl.) A.Gray, using the algorithm GARP and MaxEnt, associated with sets of environmental variables, in order to develop tools not yet used to predict invasion risk in the State of Santa Catarina. The potential niche models generated with GARP and MaxEnt algorithms proved efficient to generate potential niche models for species, indicating locations with risk of biological invasion. From this study it was observed that the niche modeling for invasive species represents an important tool for the mapping of invasions established and niche prediction for invasive species. These ecological niche models generated from the GARP and MaxEnt algorithms can provide relevant information on areas with risk of invasion to Tithonia diversifolia and Hovenia dulcis and may become a tool of institutional control in anticipation of new invasions and tracking the spread of invasive species in the State of Santa Catarina. [ABSTRACT FROM AUTHOR]

Introductions of non‐native freshwater fish continue to increase globally, although only a small proportion of these introductions will result in an invasion. These invasive populations can cause ecological impacts in the receiving ecosystem through processes including increased competition and predation pressure, genetic introgression and the transmission of non‐native pathogens. Definitions of ecological impact emphasize that shifts in the strength of these processes are insufficient for characterizing impact alone and, instead, must be associated with a quantifiable decline of biological and/or genetic diversity and lead to a measurable loss of diversity or change in ecosystem functioning. Assessments of ecological impact should thus consider the multiple processes and effects that potentially occur from invasive fish populations where, for example, impacts of invasive common carp Cyprinus carpio populations are through a combination of bottom‐up and top‐down processes that, in entirety, cause shifts in lake stable states and decreased species richness and/or abundances in the biotic communities. Such far‐reaching ecological impacts also align to contemporary definitions of ecosystem collapse, given they involve substantial and persistent declines in biodiversity and ecosystem functions that cannot be recovered unaided. Thus, while not all introduced freshwater fishes will become invasive, those species that do develop invasive populations can cause substantial ecological impacts, where some of the impacts on biodiversity and ecosystem functioning might be sufficiently harmful to be considered as contributing to ecosystem collapse. [ABSTRACT FROM AUTHOR]

Biological invasions represent a growing threat to islands and their biodiversity across the world. The isolated sub‐Antarctic island of South Georgia in the South Atlantic Ocean is a highly protected area that relies on effective biosecurity including prevention, surveillance and eradication to limit the risk of biological invasions. Based on an opportunistic field discovery, we provide the first report of an introduced ladybird beetle on South Georgia. All specimens discovered belong to the Eurasian species Coccinella undecimpunctata Linnaeus (1758) (Coleoptera: Coccinellidae). Tens of individuals of both sexes were discovered at a single location, indicating that the species may already be established on South Georgia. Transport connectivity with this site suggests that the species most likely arrived recently from the Falkland Islands as a stowaway on a ship. We discuss the implications of our discovery for the continued development of South Atlantic biosecurity. [ABSTRACT FROM AUTHOR]

Biological invasions have increased significantly with the tremendous growth of international trade and transport. Hematophagous arthropods can be vectors of infectious and potentially lethal pathogens and parasites, thus constituting a growing threat to humans—especially when associated with biological invasions. Today, several major vector-borne diseases, currently described as emerging or re-emerging, are expanding in a world dominated by climate change, land-use change and intensive transportation of humans and goods. In this review, we retrace the historical trajectory of these invasions to better understand their ecological, physiological and genetic drivers and their impacts on ecosystems and human health. We also discuss arthropod management strategies to mitigate future risks by harnessing ecology, public health, economics and social-ethnological considerations. Trade and transport of goods and materials, including vertebrate introductions and worn tires, have historically been important introduction pathways for the most prominent invasive hematophagous arthropods, but sources and pathways are likely to diversify with future globalization. Burgeoning urbanization, climate change and the urban heat island effect are likely to interact to favor invasive hematophagous arthropods and the diseases they can vector. To mitigate future invasions of hematophagous arthropods and novel disease outbreaks, stronger preventative monitoring and transboundary surveillance measures are urgently required. Proactive approaches, such as the use of monitoring and increased engagement in citizen science, would reduce epidemiological and ecological risks and could save millions of lives and billions of dollars spent on arthropod control and disease management. Last, our capacities to manage invasive hematophagous arthropods in a sustainable way for worldwide ecosystems can be improved by promoting interactions among experts of the health sector, stakeholders in environmental issues and policymakers (e.g. the One Health approach) while considering wider social perceptions. [ABSTRACT FROM AUTHOR]

Our ability to understand population spread dynamics is complicated by rapid evolution, which renders simple ecological models insufficient. If dispersal ability evolves, more highly dispersive individuals may arrive at the population edge than less dispersive individuals (spatial sorting), accelerating spread. If individuals at the low‐density population edge benefit (escape competition), high dispersers have a selective advantage (spatial selection). These two processes are often described as forming a positive feedback loop; they reinforce each other, leading to faster spread. Although spatial sorting is close to universal, this form of spatial selection is not: low densities can be detrimental for organisms with Allee effects. Here, we present two conceptual models to explore the feedback loops that form between spatial sorting and spatial selection. We show that the presence of an Allee effect can reverse the positive feedback loop between spatial sorting and spatial selection, creating a negative feedback loop that slows population spread. [ABSTRACT FROM AUTHOR]

For marine fishes, stressors such as ocean warming, biological invasions, and fisheries are suggested to drive depth redistributions. However, it is uncertain whether depth redistribution can act to offset the fitness costs associated with adverse changing conditions and allow species to maintain abundance. To better understand the relationship between global changes and depth redistribution, we synthesized bottom trawl surveys spanning two decades in the eastern Mediterranean Sea, a hotspot for warming and biological invasions, and ask three main questions: 1) have species changed their depth distributions?, 2) are patterns of depth change associated with changes in abundance? and 3) do depth and abundance changes differ by species traits and between indigenous and non‐indigenous species (NIS)? We found that patterns of depth change were highly variable. However, the relative abundances of species that exhibit deepening decreased while that of expanding species increased. Cold‐water species deepened more than warm‐water species and decreased in relative abundance. The majority of non‐indigenous fishes expanded their depth ranges over time and increased in relative abundance. The significant link between species' thermal preference and depth changes suggests that warming may drive depth redistributions. However, the variable depth change patterns imply that the hypothesis that species track climate change by deepening may be too simplistic. Finally, at least in the eastern Mediterranean, the deepening of indigenous species (IS) into colder waters was mostly associated with reduced abundance, hence deepening was not sufficient to offset the ecological impacts of global change. [ABSTRACT FROM AUTHOR]

Aim: Many invasive plant species benefit from enemy release resulting from the absence of insect herbivores in their invaded range. However, over time, specialized herbivores may 'catch up' with such invasive plants. Black locust is a tree species with a relatively limited native range in North America but has invaded large areas in virtually every temperate continent including North America. We hypothesize that both intra‐ and intercontinental spread of black locust leads to a parallel, though delayed pattern of intra‐ and intercontinental spread of insect herbivores. Location: Global. Taxon: Black locust, Robinia pseudoacacia, and its insect herbivores. Methods: We compiled historical records of the occurrence of insect herbivore species associated with R. pseudoacacia from all world regions. Based on this list, we describe taxonomic patterns and investigate associations between environmental features and numbers of non‐native specialist herbivores in the portion of North America invaded by R. pseudoacacia. Results: A total of 454 herbivorous species are recorded feeding on R. pseudoacacia across the world, with 23 of these being specialized on Robinia. From this group, seven species have successfully expanded their range beyond North America. Within North America, the richness of specialists is explained by a combination of road density, R. pseudoacacia density, distance from the R. pseudoacacia native range, and climate. Main Conclusion: Non‐native herbivore species have accumulated on invasive R. pseudoacacia in both North America and in other continents. The steady build‐up of invasions likely has diminished the enemy release that this invasive tree species has benefited from – a trend that will likely continue in the future. These findings support the hypothesis that invasive plants promote parallel though delayed invasions of specialist insect herbivores. [ABSTRACT FROM AUTHOR]

The soybean stem fly, Melanagromyza sojae (Zehntner) (Diptera: Agromyzidae), is an example of an insect pest with a restricted distribution that in the last few decades has been spreading to regions beyond its native range and causing economic losses. We evaluated whether M. sojae shifted its niche during biological invasion and used ecological niche models to estimate its global distribution under current and future climate conditions. In addition, we assessed whether the soybean stem fly represents a risk for major soybean‐producing countries, using Brazil as an example. Our analyses suggest that M. sojae has expanded its niche to new environments. Suitable habitats were predicted in all continents, including regions where this species has not yet been reported. Several soybean‐producing countries and all Brazilian growing areas are within the suitable ranges estimated for M. sojae. Also, most areas estimated as suitable under current climate conditions will remain so until at least 2080. These findings are important for invasion risk assessments aiming to prevent the spread of this species to major soybean‐producing areas. [ABSTRACT FROM AUTHOR]

The Emergency Recovery Plan for freshwater biodiversity recognizes that addressing nonnative species is one of six principal actions needed to bend the curve in freshwater biodiversity loss. This is because introduction rates of nonnative species continue to accelerate globally and where these species develop invasive populations, they can have severe impacts on freshwater biodiversity. The most effective management measure to protect freshwater biodiversity is to prevent introductions of nonnative species. Should a nonnative species be introduced, however, then its early detection and the implementation of rapid reaction measures can avoid it establishing and dispersing. If these measures are unsuccessful and the species becomes invasive, then control and containment measures can minimize its further spread and impact. Minimizing further spread and impact includes control methods to reduce invader abundance and containment methods such as screening of invaded sites and strict biosecurity to avoid the invader dispersing to neighbouring basins. These management actions have benefitted from developments in invasion risk assessment that can prioritize species according to their invasion risk and, for species already invasive, ensure that management actions are commensurate with assessed risk. The successful management of freshwater nonnative species still requires the overcoming of some implementation challenges, including nonnative species often being a symptom of degraded habitats rather than the main driver of ecological change, and eradication methods often being nonspecies specific. Given the multiple anthropogenic stressors in freshwaters, nonnative species management must work with other restoration strategies if it is to deliver the Emergency Recovery Plan for freshwater biodiversity. [ABSTRACT FROM AUTHOR]

Alien species are widely linked to biodiversity change, but the extent to which they are associated with the reshaping of ecological communities is not well understood. One possible mechanism is that assemblages where alien species are found exhibit elevated temporal turnover. To test this, we identified assemblages of vascular plants in the BioTIME database for those assemblages in which alien species are either present or absent and used the Jaccard measure to compute compositional dissimilarity between consecutive censuses. We found that, although alien species are typically rare in invaded assemblages, their presence is associated with an increase in the average rate of compositional change. These differences in compositional change between invaded and uninvaded assemblages are not linked to differences in species richness but rather to species replacement (turnover). Rapid compositional restructuring of assemblages is a major contributor to biodiversity change, and as such, our results suggest a role for alien species in bringing this about. [ABSTRACT FROM AUTHOR]

Anthropogenic biological invasions represent major concerns but enable us to investigate rapid evolutionary changes and adaptation to novel environments. The goldfish Carassius auratus with sexual diploids and unisexual triploids coexisting in natural waters is one of the most widespread invasive fishes in Tibet, providing an ideal model to study evolutionary processes during invasion in different reproductive forms from the same vertebrate. Here, using whole‐genome resequencing data of 151 C. auratus individuals from invasive and native ranges, we found different patterns of genomic responses between diploid and triploid populations during their invasion of Tibet. For diploids, although invasive individuals derived from two different genetically distinct sources had a relative higher diversity (π) at the population level, their individual genetic diversity (genome‐wide observed heterozygosity) was significantly lower (21.4%) than that of source individuals. Population structure analysis revealed that the invasive individuals formed a specific genetic cluster distinct from the source populations. Runs of homozygosity analysis showed low inbreeding only in invasive individuals, and only the invasive population experienced a recent decline in effective population size reflecting founder events. For triploids, however, invasive populations showed no loss of individual genetic diversity and no genetic differentiation relative to source populations. Regions of putative selective sweeps between invasive and source populations of diploids mainly involved genes associated with mannosidase activity and embryo development. Our results suggest that invasive diploids deriving from distinct sources still lost individual genetic diversity resulting from recent inbreeding and founder events and selective sweeps, and invasive triploids experienced no change in genetic diversity owing to their reproduction mode of gynogenesis that precludes inbreeding and founder effects and may make them more powerful invaders. [ABSTRACT FROM AUTHOR]

Understanding how the occurrence and abundance of invasive species vary over time and the environmental factors that cause such variation is important for managing and controlling invasive species. To date, studies with this perspective remain scarce in the Neotropics. We used a database describing 12 years of the occurrence of an invasive rotifer (Kellicottia bostoniensis) in a large neotropical wetland (230 km2) (upper Paraná River) since 2000. We investigated how multiple local abiotic and biotic environmental variables jointly affect occurrence and abundance of an invasive zooplankton species (K. bostoniensis). The abundance and occurrence of K. bostoniensis varied significantly over time, with a marked increase after 2009. Furthermore, biotic (native zooplankton abundance, chlorophyll-a) and abiotic (turbidity, and water level) variables were important drivers of K. bostoniensis. Whereas native zooplankton and turbidity were negatively associated with the occurrence and abundance of K. bostoniensis, chlorophyll-a and water level were positively related. Furthermore, as biotic and abiotic variables naturally fluctuate to extremes, the occurrence and abundance of K. bostoniensis were reduced. Collectively, our findings underline the important role of local variables, particularly, native zooplankton and turbidity to control the abundance and occurrence of K. bostoniensis. Our results also suggest that maintaining natural extreme oscillations of the local variables can be effective in the management of invasive species. [ABSTRACT FROM AUTHOR]

Understanding invasion mechanisms or identifying their potential outcomes has been a longstanding objective of invasion. Many recent empirical and theoretical works tend to frame a perspective of invasion biology within the field of coexistence theory. With increasing emphasis on indirect competitions, more researches hold that niche departure, intransitive loop structure or the integration of these two would be the potential mechanisms to promote native coexistence. But how invasion dynamics rely on these key properties of native competitive network is seldom investigated. Here, we introduce one alien species to a three-species competition system. By setting the structure of coexistence coefficient matrix, we consider three native coexistence mechanisms. After analyzing the equilibrium consequences of alien species invasion under these three mechanisms, we have found that (1) in the native communities supported by strong niche differentiation, alien species can certainly establish their population but would not pose great destruction to native species. (2) Invasion exclusion would happen in the community maintained by intransitive competition loop. However, whether alien species coexist with or exclude resident populations depends on both intraspecific and interspecific competition of invader. (3) The community assembled by the combination of these two mechanisms are most resistant to invasion, and where invasion consequences are more diverse. (4) Finally, the species long-term steady state and short-term respond always keep consistent. We have explicitly situated invasion process within the recent coexistence framework. Our results would broaden the understanding of invasion mechanisms and provide insights into the combination of invasion and coexistence theory. [ABSTRACT FROM AUTHOR]

Biological invasions by alien species have substantial economic impacts and are a major driver of the ongoing decline and loss of biodiversity. Through humans, the North American pond slider (Trachemys scripta) has acquired a global distribution over the last decades and is currently listed among the worst invasive reptile species. However, in more recent times, other freshwater chelonian species have increasingly been recorded far outside their native distribution ranges as well, not only on the same continent but also on others. Despite that, the impact of alien chelonians on their respective new ecosystems remains unclear. The long-term effects and severity of impacts of alien populations mostly depend on whether they ultimately succeed in establishing themselves. This is not entirely resolved for chelonians in Central Europe. To answer that, we investigated wild populations of three non-native chelonian species from North America in Germany (Pseudemys concinna, Graptemys pseudogeographica and Trachemys scripta) applying population genetic approaches. We revealed the successful reproduction of all three species in Germany and provide the very first record for the reproduction of P. concinna and G. pseudogeographica in a temperate continental climate zone outside their native distribution. Based on our unambiguous evidence of natural reproduction, we call for dedicated studies to verify how widespread established populations are and to investigate the existing and potential impacts of all three species in a range of ecosystems along a climatic gradient. Such data is urgently needed to revise the current risk assessments of non-native chelonians, especially in Central European countries. [ABSTRACT FROM AUTHOR]

A study was conducted on the biological compliance of discharged ballast water at Shanghai port from vessels with ballast water management systems (BWMS) installed. Samples were taken from 17 ships covering three ship types (cargo, tankers and containers) from 2019 to 2020. In addition, abiotic parameters including temperature, salinity, DO, pH and biotic parameters were measured. It was observed that over 80% of analyzed samples exceeded the D-2 standard. For = 50 µm organisms, the average density of living organisms ranged from 0 to 2.3×104 ind.·m-3, including 6 phyla and 13 genera of which the dominant species was Arthropoda. The species number of living = 50 µm organisms found in ballast water samples was as high as 6. For 10-50 µm organisms, the density of living organisms ranged from 0 to 156.5 cells·mL-1, including 5 phyla and 38 species of which the dominant species were Gymnodinium sp., Prorocentrum donghaiense, Cyclotella sp., Prorocentrum sp. and Platymonas sp. The species number of living 10-50 µm organisms found in ballast water samples was as high as 11. Another noteworthy result is that bacterial indicators detected in more than 40% of the ballast water samples were higher than the D-2 standard limit. Management decisions need to be made to prevent and control biosecurity issues caused by ship routes and reduce intestinal infections among residents in coastal port areas. The high percentage of non-compliant ballast water discharge after treatment at Shanghai port would significantly increase the risk of biological invasion to the local water, and preventive/mitigating measures shall be taken jointly by all involved parties. [ABSTRACT FROM AUTHOR]

Simple Summary: Sub-Antarctic islands, such as the Kerguelen Archipelago, are home to a unique collection of species because of their isolation. However, their isolation and low number of species make them more susceptible to invasion. This is particularly important as warming temperatures due to climate change are also making conditions worse for local species, and potentially better for recently introduced species, most of which are from warmer areas. The threats from non-native species in such a sensitive and unique ecosystem makes it important to understand the specific effects of climate change on non-native species to be able to predict their likely local population trajectory. In this study, we explored whether warming temperatures helped a non-native blowfly, Calliphora vicina, establish and spread throughout Kerguelen. We found that warming temperatures have made this species better able to survive and reproduce annually, and that it should continue to benefit from warming temperatures. We also discuss the potential impacts of this invasive blowfly on the local ecosystem and recommend further studies to assess its impacts and to identify management options for the species, which is likely to persist locally for the long term. The isolated sub-Antarctic islands are of major ecological interest because of their unique species diversity and long history of limited human disturbance. However, since the presence of Europeans, these islands and their sensitive biota have been under increasing pressure due to human activity and associated biological invasions. In such delicate ecosystems, biological invasions are an exceptional threat that may be further amplified by climate change. We examined the invasion trajectory of the blowfly Calliphora vicina (Robineau-Desvoidy 1830). First introduced in the sub-Antarctic Kerguelen Islands in the 1970s, it is thought to have persisted only in sheltered microclimates for several decades. Here, we show that, in recent decades, C. vicina has been able to establish itself more widely. We combine experimental thermal developmental data with long-term ecological and meteorological monitoring to address whether warming conditions help explain its current success and dynamics in the eastern Kerguelen Islands. We found that warming temperatures and accumulated degree days could explain the species' phenological and long-term invasion dynamics, indicating that climate change has likely assisted its establishment. This study represents a unique long-term view of a polar invader and stresses the rapidly increasing susceptibility of cold regions to invasion under climate change. [ABSTRACT FROM AUTHOR]

Ecological niche models have proved to be a powerful tool in assessing invasiveness risk of alien species, allowing the optimization of control strategies. Vespa velutina (Hymenoptera: Vespidae) is an invasive species with strong ecological, economical and health impacts in Europe after it was first reported in France in 2004. It was detected for the first time on a Mediterranean island (Mallorca, Balearic Islands, Spain) in 2015, where a single nest was found in the northwest of the island. Immediately, a control plan was implemented. In this study, we analysed 30 occurrence data in Mallorca island to assess the suitability distribution predicted for Mediterranean island conditions using an ensemble of small models. We obtained high values of AUC (0.9165), Somers' D (0.8331), Boyce (0.7611) and TSS (0.7754) as quality parameters of the final ensembled model. We show for the first time that there are suitable areas where this species can expand and stablish, mainly in steeper slopes and low isothermality zones. Likewise, the distribution suitability of V. velutina for other Mediterranean islands (Ibiza, Formentera, Menorca, Corsica, Sardinia, Sicily, Crete and Cyprus) was also explored, showing potentially suitable zones. This study provides valuable information regarding the areas in the Mediterranean islands under risk of invasion, and it could be used by both scientists and managers for an early detection and control of the invasive species due to its cost-effectiveness in terms of conservation. Key message: Recent invasions constitute a challenge for the application of ecological niche models. Ensemble of small models represented a novel and robust strategy to predict the distribution of Vespa velutina recent invasion in Mallorca. Climate, human and topographic influences combined explained the distribution of V. velutina. Models calibrated in Mallorca allowed to predict potentially suitable areas of invasion in other Mediterranean islands. [ABSTRACT FROM AUTHOR]

Aim: Invasive alien species are a growing problem worldwide due to their ecological, economic and human health impacts. The "killer shrimp" Dikerogammarus villosus is a notorious invasive alien amphipod from the Ponto‐Caspian region that has invaded many fresh and brackish waters across Europe. Understandings of large‐scale population dynamics of highly impactful invaders such as D. villosus are lacking, inhibiting predictions of impact and efficient timing of management strategies. Hence, our aim was to assess trends and dynamics of D. villosus as well as its impacts in freshwater rivers and streams. Location: Europe. Methods: We analysed 96 European time series between 1994 and 2019 and identified trends in the relative abundance (i.e. dominance %) of D. villosus in invaded time series, as well as a set of site‐specific characteristics to identify drivers and determinants of population changes and invasion dynamics using meta‐regression modelling. We also looked at the spread over space and time to estimate the invasion speed (km/year) of D. villosus in Europe. We investigated the impact of D. villosus abundance on recipient community metrics (i.e. abundance, taxa richness, temporal turnover, Shannon diversity and Pielou evenness) using generalized linear models. Results: Population trends varied across the time series. Nevertheless, community dominance of D. villosus increased over time across all time series. The frequency of occurrences (used as a proxy for invader spread) was well described by a Pareto distribution, whereby we estimated a lag phase (i.e. the time between introduction and spatial expansion) of approximately 28 years, followed by a gradual increase before new occurrences declined rapidly in the long term. D. villosus population change was associated with decreased taxa richness, community turnover and Shannon diversity. Main Conclusion: Our results show that D. villosus is well‐established in European waters and its abundance significantly alters ecological communities. However, the multidecadal lag phase prior to observed spatial expansion suggests that initial introductions by D. villosus are cryptic, thus signalling the need for more effective early detection methods. [ABSTRACT FROM AUTHOR]

Drosophila suzukii Matsumura, 1931 (Diptera: Drosophilidae) is an invasive pest species that causes damage to fruit crops due to premature deterioration of ripe fruits by oviposition inside them. A review of D. suzukii detections in Argentina was carried out and we updated this list with the results of our sampling in the Northwest, Cuyo and Northeast regions. The surveys carried out determined the first detections in the provinces of Jujuy and Córdoba, revealing the continuous geographical expansion of this species. [ABSTRACT FROM AUTHOR]

The green cone-headed planthopper, Acanalonia conica (Say, 1830) (Hemiptera, Fulgoromorpha, Flatidae), is native to North America and is already found in several European countries. The species is found to occur in Bulgaria and Türkiye for the first time and is the first representative of the family Acanaloniidae in both countries. The localities in Bulgaria where the species has been recorded are in the town of Malko Tarnovo, near the Turkish border, while the locality in Türkiye is in the Asiatic part of Istanbul. Data on the current distribution range in Europe, a list of plants on which A. conica has been found, and photos of the species are provided. [ABSTRACT FROM AUTHOR]

Mytella strigata (Hanley, 1843) is an invasive mussel species that has rapidly spread in China in recent years. Here, we tested the utility of three mitochondrial gene fragments, COI, 12S, and 16S, and two nuclear gene fragments, D1 28S and 18S-ITS1, for characterizing the levels of genetic diversity among and within populations using 191 M. strigata specimens collected in China to aid ongoing efforts to identify the origin of the invasion as well as molecular genetic studies. M. strigata exhibited two sex-associated haplogroups according to the COI and 12S sequences. The ratio of female-lineage to male-lineage COI and 12S sequences was 149:22 and 72:7, and the genetic distances between haplogroups were 6.56 and 9.17, respectively. Only one haplotype was detected among the 18S-ITS1 sequences (413 bp), and three haplotypes were detected among the D1 28S sequences (296 bp). The haplotype diversity of both the female-lineage COI and 12S sequences was greater than 0.5, and the nucleotide diversity of the 12S, 16S, D1 28S, and 18S-ITS1 sequences was less than 0.005 in all six populations in China. Our findings indicated that COI is the most useful gene fragment for genetic diversity studies of M. strigata populations; D1 28S and 18S-ITS1 sequences would be useful for species identification because of their low intraspecific diversity. Our genetic analysis of the COI sequences revealed Colombia as the most likely origin of M. strigata in China and showed that the invasive populations in China have recently experienced or are currently experiencing a population bottleneck. [ABSTRACT FROM AUTHOR]

Background and Aims Invasive plants often colonize wide-ranging geographical areas with various local microenvironments. The specific roles of epigenetic and genetic variation during such expansion are still unclear. Chenopodium ambrosioides is a well-known invasive alien species in China that can thrive in metalliferous habitats. This study aims to comprehensively understand the effects of genetic and epigenetic variation on the successful invasion of C. ambrosioides. Methods We sampled 367 individuals from 21 heavy metal-contaminated and uncontaminated sites with a wide geographical distribution in regions of China. We obtained environmental factors of these sampling sites, including 13 meteorological factors and the contents of four heavy metals in soils. Microsatellite markers were used to investigate the demographic history of C. ambrosioides populations in China. We also analysed the effect of epigenetic variation on metalliferous microhabitat adaptation using methylation-sensitive amplified polymorphism (MSAP) markers. A common garden experiment was conducted to compare heritable phenotypic variations among populations. Key Results Two distinct genetic clusters that diverged thousands of years ago were identified, suggesting that the eastern and south-western C. ambrosioides populations in China may have originated from independent introduction events without recombination. Genetic variation was shown to be a dominant determinant of phenotypic differentiation relative to epigenetic variation, and further affected the geographical distribution pattern of invasive C. ambrosioides. The global DNA unmethylation level was reduced in metalliferous habitats. Dozens of methylated loci were significantly associated with the heavy metal accumulation trait of C. ambrosioides and may contribute to coping with metalliferous microenvironments. Conclusions Our study of C. ambrosioides highlighted the dominant roles of genetic variation in large geographical range expansion and epigenetic variation in local metalliferous habitat adaptation. [ABSTRACT FROM AUTHOR]

Simple Summary: Biological invasions have become an ecological issue worldwide, and climate change may further influence the spread of invasive species. In this study, the latest Coupled Model Intercomparison Project Phase 6 (CMIP6) data were used to predict the suitable habitats of two invasive cryptic species, namely Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED), of the Bemisia tabaci species complex in China based on a species distribution modeling technique in current and future climate change scenarios from the present to the end of the 21st century. The results demonstrated differences in the future changes and dispersal in their suitable habitats in China under different future climatic scenarios, which suggests that climate change would have greater but divergent impacts on the potential distribution of these two invasive cryptic species. It has direct implications for developing regional management strategies in China for certain periods in the future and also provides a practical approach that can be applied to other invasive species. Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED) are two invasive cryptic species of the Bemisia tabaci species complex (Hemiptera: Aleyrodidae) that cause serious damage to agricultural and horticultural crops worldwide. To explore the possible impact of climate change on their distribution, the maximum entropy (MaxEnt) model was used to predict the potential distribution ranges of MEAM1 and MED in China under current and four future climate scenarios, using shared socioeconomic pathways (SSPs), namely SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5, over four time periods (2021–2040, 2041–2060, 2061–2080, and 2081–2100). The distribution ranges of MEAM1 and MED were extensive and similar in China under current climatic conditions, while their moderately and highly suitable habitat ranges differed. Under future climate scenarios, the areas of suitable habitat of different levels for MEAM1 and MED were predicted to increase to different degrees. However, the predicted expansion of suitable habitats varied between them, suggesting that these invasive cryptic species respond differently to climate change. Our results illustrate the difference in the effects of climate change on the geographical distribution of different cryptic species of B. tabaci and provide insightful information for further forecasting and managing the two invasive cryptic species in China. [ABSTRACT FROM AUTHOR]

Background and aims: Leucaena leucocephala (Fabaceae) has been considered one of the 100 most invasive species on a global scale. Despite its potential threat, its introduction is increasingly being promoted for agroforestry, ornamentation, shading and handicrafts in the warm and temperate forest regions of Argentina. The threat of Leucaena populations to biodiversity has been reported worldwide, where control was not effective. The aims of the present study were to update the record of naturalized populations in Argentina and provide information on the historical and current processes of naturalization and invasion. M&M: The records were documented by collecting plant material in the field and examination of material housed in herbaria. Field observations were also made to observe current naturalization processes and interaction with dispersers/predators. Results: The invasive condition was confirmed in Argentina and two introduction pathways were recognized. Based on the general appearance of the groves and the microhabitat that is generated in the invaded environments, it is considered a transformer species in Argentina. The reproductive characteristics and their interaction with other strata of regional biodiversity related to the invasive process are indicated. Conclusions: The analysis of the herbarium labels allowed detecting that in 1921 this species was already naturalized in the country. The intervention of humans in its dispersal is discussed and future scenarios are proposed. [ABSTRACT FROM AUTHOR]

The management of bio‐invasions relies upon the development of methods to trace their origin and expansion. Cointroduced parasites, especially monogenean flatworms, are ideal tags for the movement of their hosts due to their short generations, direct life cycles and host specificity. However, they are yet to be applied to trace the intraspecific movement of host lineages in their native ranges.As proof of this concept, we conducted a comparative phylogeographic analysis based upon two mitochondrial markers of a globally invasive frog Xenopus laevis and its monogenean parasite Protopolystoma xenopodis in its native range in southern Africa and invasive range in Europe.Translocation of lineages was largely masked in the frog's phylogeography. However, incongruent links between host and parasite phylogeography indicated host switches from one host lineage to another after these were brought into contact in the native range. Thus, past translocation of host lineages is revealed by the invasion success of its cointroduced parasite lineage.This study demonstrates that parasite data can serve as an independent line of evidence in invasion biology, also on the intraspecific level, shedding light on previously undetected invasion dynamics. Based upon the distribution of these invasive parasite lineages, we infer that there is widespread anthropogenic translocation of this frog, not only via official export routes, but also facilitated by the frog's use as live bait by angling communities.Synthesis and applications. Data from cointroduced, host‐specific parasites, as tags for translocation, can add value to investigations in invasion biology and conservation. A better understanding of the translocation history and resulting genetic mixing of host and parasite lineages in the native range can shed light on the genetic make‐up of parasite assemblages cointroduced to the invasive range. Knowledge of the intraspecific movement of different lineages of animals in their native ranges also has conservation implications, since contact between divergent lineages of hosts and parasites can facilitate host switches and altered parasite dynamics in both native and invasive populations. Therefore, we recommend the inclusion of parasite data as a more holistic approach to the invasion ecology of animals on the intraspecific level. [ABSTRACT FROM AUTHOR]

A central question in invasion biology is whether adaptive trait evolution following species introduction promotes invasiveness. A growing number of common‐garden experiments document phenotypic differences between native‐ and introduced‐range plants, suggesting that adaptive evolution in the new range may indeed contribute to the success of invasive plants. However, these studies are often subject to methodological pitfalls, resulting in weak evidence for post‐introduction adaptive trait evolution and leaving its role in the invasion process uncertain. In a common‐garden glasshouse study, we compared the growth, life‐history, and reproductive traits of 35 native‐ and introduced‐range Polygonum cespitosum populations. We used complementary approaches including climate‐matching, standardizing parental conditions, selection analysis, and testing for trait–environment relationships to determine whether traits that increase invasiveness adaptively evolved in the species' new range. We found that the majority of introduced‐range populations exhibited a novel trait syndrome consisting of a fast‐paced life history and concomitant sparse, reduced growth form. Selection analysis confirmed that this trait syndrome led to markedly higher fitness (propagule production) over a limited growing season that was characteristic of regions within the introduced range. Additionally, several growth and reproductive traits showed temperature‐based clines consistent with adaptive evolution in the new range. Combined, these results indicate that, subsequent to its introduction to North America over 100 generations ago, P. cespitosum has evolved key traits that maximize propagule production. These changes may in part explain the species' recent transition to invasiveness, illustrating how post‐introduction evolution may contribute to the invasion process. [ABSTRACT FROM AUTHOR]

Pollution, biological invasions and climate change pose the greatest threats to biodiversity worldwide. Few studies explore the interlink between invasive species and local pollution sites. This study describes the type and cytochemical properties of haemocytes from invasive Carcinus maenas on the southwestern Atlantic coast (Argentina). Moreover, the morphology of haemocytes and the total haemocyte count (THC) as well as the differential haemocyte count (DHC) of crabs sampled at clean or unpolluted and polluted sites were compared, to determine whether environmental stresses were evident in their haemocytes. Our results revealed two groups or subpopulations of haemocytes: hyalinocytes, as well as granulocytes and semi-granulocytes. The type of haemocyte from crabs from both sites showed no differences in their morphology. For cytochemical assays, only neutral red dye showed a more intense staining of crab haemocytes at the polluted site. All haemocytes were positive to Periodic Acid-Schiff and Sudan Black. THC of crabs from the clean site were significantly higher, as well as having a significantly higher proportion of hyalinocytes and a lower proportion of granular cells. This study provides a baseline immunological assessment for C. maenas haemocytes, suggesting a differential haemocytic response to environmental stress. [ABSTRACT FROM AUTHOR]

This work aimed to identify: (1) heterogeneity patterns in veredas, considering tree/shrubby regeneration and chemical and physical characteristics of the soil; (2) how the vereda zones (edge, intermediate and core) can influence the tree/shrubby regeneration and (3) which microenvironmental characteristics determine the distribution of native tree/shrubby regenerants and of the invasive species Pinus caribaea Morelet. For this, we collected environmental and biophysical data and sampled the regeneration of tree/shrubby species in 30 plots in two different veredas. The moisture and chemical characteristics of the soil, and regeneration composition were similar among the vereda zones, but showed important variations among sample units. In addition to soil moisture, soil chemical elements and canopy coverage characteristics also formed environmental gradients. The native tree/shrubby species occupied different positions along the environmental gradient of the veredas. The invasive species P. caribaea was more concentrated in less declined sites, in more basic and more humid soils, together with most native species. In general, the results demonstrate the absence of clear zoning, as well as the importance of environmental heterogeneity and the control of biological invasion for the maintenance of native tree/shrub regeneration. [ABSTRACT FROM AUTHOR]

Biological invasion is a worldwide phenomenon that can be considered a natural hazard. Protection against invasive plant species can only be successful if we know the anthropogenic factors that influence their occurrence, such as changes in land cover. In our study, we investigated the LUCAS based spatial distribution of five common invasive plant species (2015) and its connections with the recent (2012-2018) land CORINE based cover changes. The LUCAS points infected with this species are much closer to the CORINE land cover change polygons than the non-infected points. Our results suggest that the occurrence of Asclepias syriaca, Solidago spp, Ailanthus altissima and Robinia pseudoacacia is significantly dependent on whether land use has changed in the vicinity of LUCAS points infected with these species. Only the occurrence of Elaeagnus angustifolia does not show any correlation with changes in land cover. [ABSTRACT FROM AUTHOR]

Globalization has led to the introduction of thousands of alien species worldwide. With growing impacts by invasive species, understanding the invasion process remains critical for predicting adverse effects and informing efficient management. Theoretically, invasion dynamics have been assumed to follow an "invasion curve" (S‐shaped curve of available area invaded over time), but this dynamic has lacked empirical testing using large‐scale data and neglects to consider invader abundances. We propose an "impact curve" describing the impacts generated by invasive species over time based on cumulative abundances. To test this curve's large‐scale applicability, we used the data‐rich New Zealand mud snail Potamopyrgus antipodarum, one of the most damaging freshwater invaders that has invaded almost all of Europe. Using long‐term (1979–2020) abundance and environmental data collected across 306 European sites, we observed that P. antipodarum abundance generally increased through time, with slower population growth at higher latitudes and with lower runoff depth. Fifty‐nine percent of these populations followed the impact curve, characterized by first occurrence, exponential growth, then long‐term saturation. This behaviour is consistent with boom‐bust dynamics, as saturation occurs due to a rapid decline in abundance over time. Across sites, we estimated that impact peaked approximately two decades after first detection, but the rate of progression along the invasion process was influenced by local abiotic conditions. The S‐shaped impact curve may be common among many invasive species that undergo complex invasion dynamics. This provides a potentially unifying approach to advance understanding of large‐scale invasion dynamics and could inform timely management actions to mitigate impacts on ecosystems and economies. [ABSTRACT FROM AUTHOR]

In Patagonia (Argentina) two non-native vespid wasps became established in the last decades. Vespula germanica was first detected in 1980, while V. vulgaris arrived some 30 years later. Both species can have a strong negative impact on agro-industrial economic activities, the natural environment, and outdoor human activities. Biological invasions may be influenced negatively by the degree of interaction with the resident native community and alien species already present. The sequential arrival and coexistence of Vespula wasps in Argentina for several years allows us to understand key questions of invasion ecology. Additionally, recognizing the outcome of the invasion by vespids in Patagonia, a region lacking native social wasps, may help plan species-focused mitigation and control strategies. We explored the role of competition in terms of invasion success, and the strategies that promote coexistence. Two possible scenarios, using niche overlap indices and isocline equations, were proposed to determine competition coefficients. Using a simple mathematical modeling framework, based on field collected data, we show that food resources do not play a central role in competitive interaction. The competition coefficients obtained from the equations were different from those inferred from the overlap indices (0.53 and 0.54–0.076 and 0.197, respectively). Together, these findings suggest that no matter the arrival order, V. vulgaris, always reaches higher densities than V. germanica when both species invade new regions. Our work contributes to further our understanding on the worldwide invasion processes deployed by these two eusocial insects. [ABSTRACT FROM AUTHOR]