Search

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]

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]

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]

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]

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]

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 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]

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]

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]

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]

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]

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]

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]

Simple Summary: Knowledge of where invasive species could potentially establish (potential distribution) is critical to prioritizing and addressing biological invasion threats. In this study, we predicted the potential distribution of Calonectriapseudonaviculata (Cps), an invasive fungal pathogen that blights boxwood, an iconic landscape plant, major evergreen nursery crop, and keystone forest species. We used climate data, presence records from Europe and western Asia, and multiple modeling approaches to predict the potential distribution of Cps at regional and global scales and to explore the roles of temperature and moisture in shaping its distribution. Model predictions were validated using an independent presence record dataset. A consensus map of model predictions revealed that Cps could potentially spread and establish well beyond its currently invaded range in Europe, western Asia, New Zealand, United States and Canada. These include a number of not-yet-invaded areas in eastern and southern Europe, North America, and many regions of the world where boxwood is native. This knowledge informs policymakers and other stakeholders in these areas on the need for implementing a strict phytosanitary protocol for risk mitigation of accidental introduction, having an effective surveillance for early detection, and developing a recovery plan for the pathogen when accidental introductions occur. Boxwood blight caused by Cps is an emerging disease that has had devastating impacts on Buxus spp. in the horticultural sector, landscapes, and native ecosystems. In this study, we produced a process-based climatic suitability model in the CLIMEX program and combined outputs of four different correlative modeling algorithms to generate an ensemble correlative model. All models were fit and validated using a presence record dataset comprised of Cps detections across its entire known invaded range. Evaluations of model performance provided validation of good model fit for all models. A consensus map of CLIMEX and ensemble correlative model predictions indicated that not-yet-invaded areas in eastern and southern Europe and in the southeastern, midwestern, and Pacific coast regions of North America are climatically suitable for Cps establishment. Most regions of the world where Buxus and its congeners are native are also at risk of establishment. These findings provide the first insights into Cps global invasion threat, suggesting that this invasive pathogen has the potential to significantly expand its range. [ABSTRACT FROM AUTHOR]

While reducing the species richness of invaded communities is a well‐known consequence of biological invasions, non‐native species can also reduce variability between communities over time (i.e. beta diversity) in a process known as biotic homogenization. Although biotic homogenization due to non‐native species is a common topic of theoretical reviews, we believe no global meta‐analysis on the effect of non‐native species on beta diversity has been carried out yet. Here, we systematically show that non‐native species drive biotic homogenization, but it depends on the realm, beta diversity facet and study design. Biotic homogenization was more intense in marine and freshwater ecosystems than in terrestrial ecosystems. We also found that non‐native species reduced both taxonomic and phylogenetic beta diversity, but not the functional beta diversity. Finally, we observed more intense effects using 'before versus after invasion' followed by 'uninvaded versus invaded sites' while the effect size of studies using 'communities associated with native versus non‐native species' did not differ from zero. Our findings highlight that non‐native species contribute to biotic homogenization as a prevalent pattern in communities worldwide, and that biodiversity conservation strategies should go beyond investigating the reduction in the number of species by also taking into account beta diversity in its multiple facets. [ABSTRACT FROM AUTHOR]

Biological invasions can have major impacts on freshwater and marine ecosystems. Therefore, it is vital that non-indigenous species are accurately identified and reported when potential or confirmed invasions occur. The present study reports the first occurrence of Marenzelleria neglecta (Annelida, Spionidae) and the spread of Laonome xeprovala (Annelida, Sabellidae) in the Danube Delta–Black Sea ecosystem. Spionidae is one of the most diverse families of annelid worms and is a dominant group in terms of the number of species that have been introduced to non-native areas, while the members of Sabellidae are among the most visible polychaetes commonly found in fouling communities and are colonizing new geographic areas. Based on 20 samples collected in 2021, we provide an overview of the distribution of the investigated species and possible arrival pathways for Marenzelleria neglecta. Specimens were identified based on morphological descriptions. Both species have invasive behaviour, colonizing large areas in relatively short time periods and reaching relatively high densities (M. neglecta—1400 ind.m−2; L. xeprovala—40 ind.m−2). Due to their distribution and high abundances, the biology and ecology of these species in the Danube River–Danube Delta–Black Sea system need to be investigated further in order to assess their impact on ecosystem structure and functioning. [ABSTRACT FROM AUTHOR]

Information about occurrences of alien species is often provided in so-called checklists, which represents lists of reported alien species in a region. In many cases, available checklists cover whole countries, which is too coarse for many analyses and limits capabilities of assessing status and trends of biological invasions. Information about point-wise occurrences is available in large quantities at online facilities such as GBIF and OBIS, which, however, do not provide information about the invasion status of individual populations. To close this gap, we here provide a semi-automated workflow called DASCO to downscale regional checklists using occurrence records obtained from GBIF and OBIS. Within the workflow, coordinate-based occurrence records for species listed in the provided regional checklists are obtained from GBIF and OBIS, and the status of being an alien population is assigned using the information in the provided checklists. In this way, information in checklists is made available at the local scale, which can then be re-allocated to any other spatial categorisation as provided by the user. In addition, habitats of species are determined to distinguish between marine, brackish, terrestrial, and freshwater species, which allows splitting the provided checklists to the respective realms and ecoregions. By using checklists of global databases, we showcase the usage of the DASCO workflow and revealed > 35 million occurrence records of alien populations in terrestrial and marine regions worldwide, which were back-transformed to terrestrial and marine regions for comparison. DASCO has the potential to be used as a basis for the widely applied species distribution models or assessments of status and trends of biological invasions at large geographic scales. The workflow is implemented in R and in full compliance with the FAIR data principles of open science. [ABSTRACT FROM AUTHOR]

Biological invasions are a leading threat to biodiversity globally. Increasingly, ecosystems experience multiple introductions, which can have significant effects on patterns of diversity. The way these communities assemble will depend partly on whether rare and common alien species respond to environmental predictors in the same manner as rare and common native species, but this is not well understood. To examine this question across four national parks in south‐eastern Australia, we sampled the understory plant community of eucalypt‐dominated dry forest subject to multiple plant introductions. The drivers of diversity and turnover in alien and native species of contrasting frequency of occurrence (low, intermediate, and high) were each tested individually. We found alien species diversity and turnover were both strongly associated with abiotic conditions (e.g., soil pH), while distance had little influence because of the greater extent of occurrence and more homogeneous composition of common aliens. In contrast, native species diversity was not associated with abiotic conditions and their turnover was as strongly influenced by distance as by abiotic conditions. In both alien and native species, however, the most important predictors of turnover changed with frequency of occurrence. Although local coexistence appears to be facilitated by life history trade‐offs, species richness of aliens and natives was negatively correlated and native species might face greater competition in areas with more neutral soils (e.g., pH > ~5.5) where alien richness and relative frequency were both highest. We conclude that diversity and turnover in the generally more widespread alien species are mainly driven by species sorting along an environmental gradient associated with pH and nutrient availability, whereas turnover of native species is driven by more neutral processes associated with dispersal limitation. We show alien and native plant species respond to different environmental factors, as do rare and common species within each component. [ABSTRACT FROM AUTHOR]

In this paper, we study the global dynamics and asymptotic spreading speed for a biological invasion model with free boundaries and time delay. Given a suitable initial value compatibility condition, the well-posedness of solution is established and some sufficient conditions for spreading and vanishing are derived. Furthermore, by studying an associated semi-wave solution problem, the asymptotic spreading speed for the invasive species is given. It is shown that time delay can slow down the spreading speed. Finally, the dynamics and asymptotic spreading speed are analyzed by numerical simulations. [ABSTRACT FROM AUTHOR]

Lablab purpureus (Fabaceae) is a species native to tropical Africa, but widely cultivated and naturalized in many tropical and sub-tropical countries. We report the occurrence of this species for the first time in Sicily, close to the town of Palermo. The population seems to be well established and takes part to a sub-nitrophilous vegetation dominated by Oloptum miliaceum, representing the first case of naturalization of this species in Italy. [ABSTRACT FROM AUTHOR]

We report the discovery of a population of the exotic North African Water Frog Pelophylax saharicus around the Etang de Berre, on the Mediterranean coast of France, about 25 km north-west of Marseille. The animals had been originally identified as P. perezi or P. kl. grafi by a combination of acoustic and morphological characters and their true identity was not revealed until three samples from one locality were included in a large-scale genomic work dedicated to the genus Pelophylax. Mitochondrial barcoding of the samples from other areas around Etang de Berre did not detect any native P. perezi or P. kl. grafi and confirmed that P. saharicus has spread to several localities, does reproduce and has been present since 2011 at least. We suggest that dedicated field work is needed as soon as possible to (i) map the extant of P. saharicus 's distribution around the Etang de Berre, (ii) establish if populations of the native P. perezi – kl. grafi system still persist around the Etang de Berre or not and (iii) check if P. saharicus has spread to neighboring areas or not. Depending on the answers to these three questions, local conservationists will need to evaluate the feasibility and relevance of any action to control the spread of this new invasive species and attempt to eradicate it. [ABSTRACT FROM AUTHOR]

Understanding how alien species assemble is crucial for predicting changes to community structure caused by biological invasions and for directing management strategies for alien species, but patterns and drivers of alien species assemblages remain poorly understood relative to native species. Climate has been suggested as a crucial filter of invasion-driven homogenization of biodiversity. However, it remains unclear which climatic factors drive the assemblage of alien species. Here, we compiled global data at both grid scale (2,653 native and 2,806 current grids with a resolution of 2°   ×   2°) and administrative scale (271 native and 297 current nations and sub-nations) on the distributions of 361 alien amphibians and reptiles (herpetofauna), the most threatened vertebrate group on the planet. We found that geographical distance, a proxy for natural dispersal barriers, was the dominant variable contributing to alien herpetofaunal assemblage in native ranges. In contrast, climatic factors explained more unique variation in alien herpetofaunal assemblage after than before invasions. This pattern was driven by extremely high temperatures and precipitation seasonality, 2 hallmarks of global climate change, and bilateral trade which can account for the alien assemblage after invasions. Our results indicated that human-assisted species introductions combined with climate change may accelerate the reorganization of global species distributions. [ABSTRACT FROM AUTHOR]

Aim: Biological invasions represent one of the main anthropogenic drivers of global change with a substantial impact on biodiversity. This impact can be particularly acute in biodiversity hotspots. Ligustrum lucidum W.T. Aiton is a tree species native of China that, from as early as the eighteenth century, has been introduced broadly around the globe, becoming a serious invasive species. We aim to predict L. lucidum's current and future potential distributions at a global scale and assess the degree to which biodiversity hotspots are at risk of invasion. Location: All continents. Methods: Using global presence data, climatic and edaphic variables, we developed an ensemble model to predict current and future periods (2050 and 2080) global distribution of L. lucidum. Susceptible countries and hotspots of biodiversity were identified. Results: Important regions within China and neighbouring countries are likely to be environmentally suitable, but they are not currently occupied. Biodiversity hotspots in South America are highlighted as being at current risk of invasion. Notably, climate change may increase risks across large extents of biodiversity hotspots, mainly in South America and Africa, especially by 2080 period. Main conclusions: Current and future potential distribution of L. lucidum overlaps with biodiversity hotspots worldwide. Control of L. lucidum is a challenge once established. Thus, species distribution modelling helps to identify risk areas, guiding their early detection in current or future suitable areas. Our findings can be useful as a guide to develop region‐specific invasion management strategies to prevent and/or control this species' spread. [ABSTRACT FROM AUTHOR]

Aim: Biogeographic boundaries can act as either weak or strong barriers to the spread of species undergoing distributional change. Once a novel species spreads across a boundary, it can have a substantial impact on the ecosystem, for instance by competing with local species, and, over the long‐term, re‐engineer the ecosystem. Marine biogeographic regions are clearly defined on the coast of southern Africa and we tested the influence of their boundaries on the spread and spatial structure of an alien ecosystem engineer. Location: Southern Africa. Taxon: An invasive mussel, Mytilus galloprovincialis. Methods: Records of M. galloprovincialis were compiled into a database to determine its decadal patterns of spread across multiple bioregions. Distribution and abundance (estimated using density and semi‐quantitative abundance scale [ACFOR]) of this mussel were surveyed to determine patterns in spatial structure across bioregions. In addition, we compared the size structure of populations at the eastern margins of its range with those of larger populations nearer the range centre. Results: Initial breaching of biogeographic boundaries was associated with rapid spread, but other boundaries encountered decades later acted as barriers to further spread. Across >2,800 km of coast, spatial autocorrelation was observed in densities (low and mid shore levels) and in ACFOR abundances. Repeating spatial patterns in densities and ACFOR abundance were detected at scales of 120–160 km and of 400–990 km. Considerable effort was required to detect populations at the absolute eastern limits of its distribution. Main conclusion: Detection of spatial structures at multiple scales suggests that ecologically determined processes regulate abundance at both intra‐bioregional and inter‐bioregional scales, which may help tease apart the historic and contemporary consequences of interspecific interactions on the structure of rocky shore communities. This study demonstrates the influence of biogeography in driving temporal patterns of spread and spatial structure on the distribution and abundance of an invasive species. [ABSTRACT FROM AUTHOR]

Understanding how the biological invasion is driven by environmental factors will improve model prediction and advance early detection, especially in the context of accelerating anthropogenic ecological changes. Although a large body of studies has examined how favorable environments promote biological invasions, a more comprehensive and mechanistic understanding of invasive species response to unfavorable/stressful conditions is still developing. Grass invasion has been problematic across the globe; in particular, C4 grass invaders, with high drought tolerance, adaptations to high temperatures, and high water use efficiency, could become more severe. Here, we conducted a rigorous microcosm experiment, with one of the most damaging invasive C4 grass, cogongrass (Imperata cylindrica), to explore how cogongrass responds to soil water and nutrient stress. We further integrated the results of the microcosm study with a species distribution model to (1) corroborate greenhouse results with field observations and (2) validate the robustness of our findings at subcontinental scales. Both the microcosm experiments and species distribution model agreed that soil water stress had a stronger impact on cogongrass than the nutrient one. New vegetative growth of cogongrass continued to be inhibited by the prior water stress. The significant water effect on cogongrass total biomass was supported by the finding that both allometric and biochemical traits of cogongrass did not show significant responses to the changes in water treatment. Different to the conventional wisdom that nutrient enrichment plays a bigger role in facilitating biological invasions, this study highlighted the possibility that water conditions may have a more substantial effect on some aggressive invaders. Therefore, an important implication of this study on biological conservation is that field managers might take advantage of the negative effect of global drought on some invasive species to increase the efficiency of their controlling efforts because invasive species may become more vulnerable under drought effect. [ABSTRACT FROM AUTHOR]

Recognising which life‐history factors can potentially explain the success of biological invasions is essential to understand why certain exotic species are more successful to invade a given system than others, and also to better predict invasion outcomes. We focused on the three most planted pine tree species in Southern Brazil – Pinus elliottii, P. caribaea and P. oocarpa – as a natural system to test the hypothesis that some key vital attributes – fecundity (number of seeds produced), seed viability, germinability, seedling growth vigour (biomass and stem length) – could be driving the greater invasion of P. elliottii in the region. We collected seeds of P. elliottii var. elliottii, P. caribaea subsp. hondurensis and P. oocarpa in two sites of similar climate and soil in the Cerrado biodiversity hotspot. Seeds were tested for viability and germinability, and seed production was estimated. Under laboratory conditions, we evaluated seedling survival, stem and root development, biomass production and mortality for each species. Although P. elliottii is regarded as the most successful invasive pine species in the Cerrado, it did not outperform the other pines in terms of seed viability, germinability and seedling survival, and it had the slowest growth. P. elliottii did produce, however, at least twice as many seeds as the other species. P. caribaea revealed high seed viability and seedling survival, the fastest seedling development, but low seed production. P. oocarpa showed the lowest seed viability, but fast root growth and very low seedling mortality. Our results suggest seed production is a key factor for P. elliottii invasion success. However, given the strong performance of P. caribaea and P. oocarpa for germinability and growth, we emphasise the risk of both species also becoming successful invaders in the Cerrado. We highlight the need for constant monitoring of emerging pine individuals in native ecosystems to avoid future invasions. [ABSTRACT FROM AUTHOR]

Ecological processes often exhibit time lags. For plant invasions, lags of decades to centuries between species' introduction and establishment in the wild (naturalisation) are common, leading to the idea of an invasion debt: accelerating rates of introduction result in an expanding pool of introduced species that will naturalise in the future. Here, I show how a concept from survival analysis, the hazard function, provides an intuitive way to understand and forecast time lags. For plant naturalisation, theoretical arguments predict that lags between introduction and naturalisation will have a unimodal distribution, and that increasing horticultural activity will cause the mean and variance of lag times to decline over time. These predictions were supported by data on introduction and naturalisation dates for plant species introduced to Britain. While increasing trade and horticultural activity can generate an invasion debt by accelerating introductions, the same processes could lower that debt by reducing lag times. [ABSTRACT FROM AUTHOR]

The introduction of alien species is one of the main problems in conservation. Many successful invaders cause severe economic and ecological damage. Such is the case of Leptoglossus occidentalis, a phytophagous true bug native to North America, which has become a pest in Europe, Asia, Africa and South America. Within the genus, another species whose distributional range is expanding toward the east of North America is Leptoglossus clypealis. As climate determines the successful establishment of insects, the identification of climatically suitable areas for invasive species based on ecological niche models (ENMs) offers an excellent opportunity for preventing invasions. In this study, ENMs were built for both species and their native climatic niches were compared. Their niche breath was also measured. The climatic niches of both species are identical and the niche breadth of L. clypealis is broader than that of L. occidentalis. In view of the great ecological resemblance between these two species, we believe that L. clypealis could became a major pest thus it should be carefully monitored. The results of the present worldwide ENMs showed numerous regions with suitable conditions for the establishment of both species. The future ENMs exhibited a retraction in the suitable areas in North America, Europe and Asia. [ABSTRACT FROM AUTHOR]

Biological invasions, the establishment and spread of non‐native species in new regions, can have extensive economic and environmental consequences. Increased global connectivity accelerates introduction rates, while climate and land‐cover changes may decrease the barriers to invasive populations spread. A detailed knowledge of the invasion history, including assessing source populations, routes of spread, number of independent introductions, and the effects of genetic bottlenecks and admixture on the establishment success, adaptive potential, and further spread, is crucial from an applied perspective to mitigate socioeconomic impacts of invasive species, as well as for addressing fundamental questions on the evolutionary dynamics of the invasion process. Recent advances in genomics together with the development of geographic information systems provide unprecedented large genetic and environmental datasets at global and local scales to link population genomics, landscape ecology, and species distribution modeling into a common framework to study the invasion process. Although the factors underlying population invasiveness have been extensively reviewed, analytical methods currently available to optimally combine molecular and environmental data for inferring invasive population demographic parameters and predicting further spreading are still under development. In this review, we focus on the few recent insect invasion studies that combine different datasets and approaches to show how integrating genetic, observational, ecological, and environmental data pave the way to a more integrative biological invasion science. We provide guidelines to study the evolutionary dynamics of invasions at each step of the invasion process, and conclude on the benefits of including all types of information and up‐to‐date analytical tools from different research areas into a single framework. [ABSTRACT FROM AUTHOR]

Biological invasions have become increasingly prevalent in marine ecosystems, modifying biodiversity and altering the way ecosystems function. Understanding how variation in environmental factors influences the success of non‐native species, especially their early life stages, can be a crucial step in identifying habitats that are under threat of invasion, and in predicting how rapidly and far these species may spread once they arrive in novel habitats. The invasive marine macroalga Sargassum horneri was first observed in Long Beach Harbor, CA, USA in 2003, and has since spread throughout the Southern California Bight and along the Baja California Peninsula, MEX where it now forms dense stands on subtidal rocky reefs and displaces native habitat‐forming macroalgae. We examined how variation in temperature, nutrients, and irradiance affect survival, growth, and development in S. horneri early life stages over a three‐week period. Our experimental treatments consisted of orthogonally crossed temperatures (10, 15, 20, and 25°C), nutrient concentrations (ambient and nutrient‐enriched seawater), and irradiances (50 and 500 µmol photons · m−2 · s−1). Overall, temperature exerted the greatest influence on S. horneri's germling and juvenile life stages, with moderate temperatures facilitating their greatest survival, growth, and development. In contrast, fewer germlings developed fully under the lowest or highest temperatures, and juvenile survival and growth were reduced, especially when combined with low irradiances. Together, our data suggest that ocean temperatures of or below 10˚C and of or above 25°C may slow, but likely not stop, S. horneri's northward and southward expansion along the California and Baja California coasts. [ABSTRACT FROM AUTHOR]

Invasive species have considerably increased in recent decades due to direct and indirect effects of ever‐increasing international trade rates and new climate conditions derived from global change. We need to better understand how the dynamics of early species invasions develop and how these result in impacts on the invaded ecosystems. Here we studied the distribution and severe defoliation processes of the box tree moth (Cydalimaperspectalis W.), a tree defoliator insect native to Asia and invasive in Europe since 2007, through the combination of species distribution models based on climate and landscape composition information. The results showed that the combination of data from the native and the invaded areas was the most effective methodology for the appropriate invasive species modeling. The species was not influenced by overall landscape factors, but only by the presence of its host plant, dispersal capacity, and climate suitability. Such climate suitability was described by low precipitation seasonality and minimum annual temperatures around 0°C, defining a continentality effect throughout the territory. We emphasize the need of studying distribution and severe defoliation processes separately because we identified that climate suitability was slightly involved in limiting species spread processes but strongly constrained ecosystem impact in terms of defoliation before the species reaches equilibrium with the new environment. New studies on habitat recovery after disturbance, ecological consequences of such impact, and community dynamics in a context of climate change are required for a better understanding of this invasive species. [ABSTRACT FROM AUTHOR]

Lizard thermoregulation is costly and is largely behavioural. Podarcis raffonei, endemic of few islets of the Aeolian archipelago (southern Italy), is one of the most threatened lizards in Europe, its survival being under threat also due to the presence of the congeneric P. siculus, a successful invader characterised by behavioural plasticity and effectiveness and precision at regulating body temperature (Tb). We tested whether thermoregulation behaviour diverges between the two species by analysing (i) the heating rates under a standard thermal condition, and (ii) the temperature at which lizards ended basking (Tfinal) along a thermal gradient. Overall, we found behavioural differences between the two lizards (i.e. P. siculus exhibited lower Tfinal), although both species had comparable heating rates and thermoregulated in the same thermal conditions. The invasive P. siculus had lower Tfinal and, since heating rates were similar between species, it expended less time basking than native P. raffonei. We speculate that the observed thermal ecology differences could provide a selective advantage to P. siculus in the harsh island environment. [ABSTRACT FROM AUTHOR]

Human visitors are associated with the unintended dispersal of weeds, seeds and pathogens across ecological communities. With the increasing popularity of nature‐based tourism, access to protected areas has increased, in turn increasing the risks of unintended dispersal of exotic species to these areas.Here, we assess the potential contribution of both international and domestic visitors travelling within New Zealand to the spread of exotic species. To get an overview of the visitors' travelling patterns across the country, we constructed visitation networks at two spatial scales—a regional scale (which is a coarse scale) and a local territorial scale (which is a finer scale).We then used a Mixed Membership Stochastic Block Model to identify characteristic groups of visitors and places based on the similarities of the visitors' travelling patterns across the country. Overall, we found that there are 10 characteristic groups of visitors travelling to 12 characteristic groups of places at the regional scale and 6 characteristic groups of visitors travelling to 6 characteristic groups of places at the territorial scale.The resulting characteristic travelling patterns of the visitors across New Zealand further allowed us to estimate the different visitor groups' likelihood to travel to protected areas. Overall, we found that some visitor groups are much more likely than others to travel to protected areas of high protection status, at both spatial scales.Synthesis and applications. Our results highlight the importance of accounting for human behaviour—that is, understanding how visitors travel to places—when assessing human‐mediated dispersal. More specifically, we illustrate how to assess the relative contribution of a potential vector dispersing exotic species based on their travelling patterns—especially in cases where the target exotic species are not yet identified or when there is limited information regarding the dispersal routes of exotic species and their potential vectors. As a result, our work offers a holistic perspective on human‐mediated dispersal of exotic species. Moreover, it provides a potential baseline against which both field biologists and practitioners can identify areas that would benefit from further investigation to better understand invasion processes in their focal systems. [ABSTRACT FROM AUTHOR]

Among the principal causes producing detrimental effects on global biodiversity are introductions of alien species. Very few attempts to control introduced amphibians and reptiles in Middle America (Mexico and Central America) can be identified, so listings are provided for 24 exotic species, 16 translocated species, and 11 species that were removed from the introduced species listing because of lack of substantiating evidence that they are from established populations. Biosecurity methods are also identified that can be applied for preventing, controlling, and managing introduced and especially invasive species. [ABSTRACT FROM AUTHOR]

Biological invasion is a global problem with large negative impacts on ecosystems and human societies. When a species is introduced, individuals will first have to pass through the invasion stages of uptake and transport, before actual introduction in a non‐native range. Selection is predicted to act during these earliest stages of biological invasion, potentially influencing the invasiveness and/or impact of introduced populations. Despite this potential impact of pre‐introduction selection, empirical tests are virtually lacking. To test the hypothesis of pre‐introduction selection, we followed the fate of individuals during capture, initial acclimation, and captivity in two bird species with several invasive populations originating from the international trade in wild‐caught pets (the weavers Ploceus melanocephalus and Euplectes afer). We confirm that pre‐introduction selection acts on a wide range of physiological, morphological, behavioral, and demographic traits (incl. sex, age, size of body/brain/bill, bill shape, body mass, corticosterone levels, and escape behavior); these are all traits which likely affect invasion success. Our study thus comprehensively demonstrates the existence of hitherto ignored selection acting before the actual introduction into non‐native ranges. This could ultimately change the composition and functioning of introduced populations, and therefore warrants greater attention. More knowledge on pre‐introduction selection also might provide novel targets for the management of invasive species, if pre‐introduction filters can be adjusted to change the quality and/or quantity of individuals passing through such that invasion probability and/or impacts are reduced. [ABSTRACT FROM AUTHOR]

Introduced species may threaten both biodiversity and agriculture, necessitating an understanding on the factors that influence their distribution, and the efficacy of control measures. In Tasmania, Australia, the introduced rainbow lorikeet (Trichoglossus moluccanus) may be widespread, but data on where they occur and the efficacy of control methods are limited. We used an occupancy modelling framework (presence–absence data) to undertake a survey of two populations of invasive rainbow lorikeets to: (i) understand their distribution across the north and south of the island, and (ii) evaluate the impact of removing birds from the southern population by quantifying occupancy before (2016) and after (2018) removal. The best model explaining occupancy in both populations included a negative relationship with distance from central urban areas. We found no change in site occupancy or detectability in the southern population after removal of 208 birds (potentially comprising >50% of their original population size). This result may be explained by one of three possibilities: (i) the population is larger than previously thought, (ii) the population recovered quickly after reduction, or (iii) removal of birds reduced population density but not area of occupancy. We highlight the importance of urban habitats for the invasive rainbow lorikeet and suggest that alternative methods (e.g. abundance/density‐based monitoring) may better detect impacts of removal. [ABSTRACT FROM AUTHOR]

Aquatic invasive species negatively impact the native aquatic communities in many parts of the world. Every nation faces the issue of introduced species, but the efforts to manage them depend on the varying capacity and willingness to manage invasions globally. Aquatic invasive species have their own set of challenges; it is crucial to understand the invasion dynamics of these species as well as their nature of interaction with humans to devise better mitigation processes. The freshwater aquatic wealth of India is seriously threatened by pollution, flow modification, overexploitation, habitat degradation and invasive alien species. India has several globally known freshwater invasive species. This article explores the invasion dynamics, potential pathways of invasion and impacts of the introduction of two of the world's top 100 invasive species, which remain relatively unknown in India: Gambusia affinis and Gambusia holbrooki. In the early 19th century, Gambusia species were introduced into Lalbagh Lake, Bengaluru, and eventually to other parts of the country. Gambusia is now widely distributed in the wild and in many Protected Areas, where it has become a threat to endangered amphibians, fishes and other aquatic invertebrates. This article explores the distribution of these Gambusia species in India and the drivers leading to their invasion. It also explains the obscure history of Gambusia invasion in India and the lack of awareness of its possible negative impacts. The importance of using molecular tools in taxonomy and their applications in invasion ecology are discussed. This study highlights the research gaps in invasion ecology of this genus in India and suggests scientific methods to manage these invasive species. [ABSTRACT FROM AUTHOR]