Global threats from invasive alien species in the twenty-first century and national response capacities

Stable isotope analysis in food web research: Systematic review and a vision for the future for the Baltic Sea macro-region

Food web research provides essential insights into ecosystem functioning, but practical applications in ecosystem-based management are hampered by a current lack of knowledge synthesis. To address this gap, we provide the first systematic review of ecological studies applying stable isotope analysis, a pivotal method in food web research, in the heavily anthropogenically impacted Baltic Sea macro-region. We identified a thriving research field, with 164 publications advancing a broad range of fundamental and applied research topics, but also found structural shortcomings limiting ecosystem-level understanding. We argue that enhanced collaboration and integration, including the systematic submission of Baltic Sea primary datasets to stable isotope databases, would help to overcome many of the current shortcomings, unify the scattered knowledge base, and promote future food web research and science-based resource management. The effort undertaken here demonstrates the value of macro-regional synthesis, in enhancing access to existing data and supporting strategic planning of research agendas.

Mammals of the Tandilia Mountain system, current species inhabiting Pampean highland grasslands

Neotropical temperate grasslands comprise the Pampas ecoregion in Argentina. This region is also the center of agricultural development in Argentina, which has led to a significant simplification and homogenization of the landscape. The Tandilia Mountains, located in the Southeast of the ecoregion, house one of the last remnants of the highland grassland that acts as a refuge for several native species, including both endemic and threatened species. This work aims to present an updated inventory of mammal species that inhabit the highland grassland remnants of the Tandilia Mountains. We used several sources of information to compile the list, including museum collections, citizen science projects (i.e., iNaturalist, EcoRegistros, and Argentinian Network for Monitoring Run Over Fauna), literature, and personal observations. We recorded 40 species of mammals, which include 32 native species and eight exotic species. The richest orders were Rodentia (42.5%), Chiroptera (17.5%), and Carnivora (12.2%). The native mammals found in the Tandilia Mountains represent 44% of the mammal diversity of the Pampas ecoregion, among which there are endemic species of the ecoregion, species whose populations are declining globally, and threatened species. Unfortunately, the presence of protected areas in the system is limited to a few small ones, which highlights the urgency of increasing the number and variety of protected areas. The information presented in this work contributes to the knowledge of biodiversity and the planning of conservation actions for the last remnants of highland grasslands.

New indicators of ecological resilience and invasion resistance to support prioritization and management in the sagebrush biome, United States

Ecosystem transformations to altered or novel ecological states are accelerating across the globe. Indicators of ecological resilience to disturbance and resistance to invasion can aid in assessing risks and prioritizing areas for conservation and restoration. The sagebrush biome encompasses parts of 11 western states and is experiencing rapid transformations due to human population growth, invasive species, altered disturbance regimes, and climate change. We built on prior use of static soil moisture and temperature regimes to develop new, ecologically relevant and climate responsive indicators of both resilience and resistance. Our new indicators were based on climate and soil water availability variables derived from process-based ecohydrological models that allow predictions of future conditions. We asked: (1) Which variables best indicate resilience and resistance? (2) What are the relationships among the indicator variables and resilience and resistance categories? (3) How do patterns of resilience and resistance vary across the area? We assembled a large database (n = 24,045) of vegetation sample plots from regional monitoring programs and derived multiple climate and soil water availability variables for each plot from ecohydrological simulations. We used USDA Natural Resources Conservation Service National Soils Survey Information, Ecological Site Descriptions, and expert knowledge to develop and assign ecological types and resilience and resistance categories to each plot. We used random forest models to derive a set of 19 climate and water availability variables that best predicted resilience and resistance categories. Our models had relatively high multiclass accuracy (80% for resilience; 75% for resistance). Top indicator variables for both resilience and resistance included mean temperature, coldest month temperature, climatic water deficit, and summer and driest month precipitation. Variable relationships and patterns differed among ecoregions but reflected environmental gradients; low resilience and resistance were indicated by warm and dry conditions with high climatic water deficits, and moderately high to high resilience and resistance were characterized by cooler and moister conditions with low climatic water deficits. The new, ecologically-relevant indicators provide information on the vulnerability of resources and likely success of management actions, and can be used to develop new approaches and tools for prioritizing areas for conservation and restoration actions.

Distribution of Freshwater Alien Animal Species in Morocco: Current Knowledge and Management Issues

This work presents currently available knowledge on alien species (AS) found in the inland waters of Morocco. The objective is to provide an updated list of alien species and identify the main introduction pathways and possible threats to native biodiversity. The dataset was built from an extensive literature search supplemented by our own research work (published or in progress). The main areas harboring xenodiversity in Moroccan freshwaters correspond to protected areas (e.g., Ramsar Site and SIBE). These areas are currently home to 41 confirmed AS belonging to different taxonomic groups. Fish are the most abundant taxonomic group with 21 species, followed by molluscs (7 species) and arthropods (7 species). The presence of 15 more species was also noticed but considered doubtful. Almost half of these AS were introduced intentionally. They correspond to restocking programs and are likely the most serious threat to native biodiversity through predation, competition, and hybridization. Commercial activities around aquarium and ornamental species appear as the second source favoring colonization by AS. Implementing protective regulations regarding the import of exotic species in Morocco appears very urgent to protect local native diversity. In addition, detecting and monitoring the expansion of AS within the colonized areas and studies improving biological and ecological knowledge seem crucial to mitigate their possible impacts on native communities and preserve Moroccan freshwater ecosystems.

Forest Insect Biosecurity: Processes, Patterns, Predictions, Pitfalls

The economic and environmental threats posed by non-native forest insects are ever increasing with the continuing globalization of trade and travel; thus, the need for mitigation through effective biosecurity is greater than ever. However, despite decades of research and implementation of preborder, border, and postborder preventative measures, insect invasions continue to occur, with no evidence of saturation, and are even predicted to accelerate. In this article, we review biosecurity measures used to mitigate the arrival, establishment, spread, and impacts of non-native forest insects and possible impediments to the successful implementation of these measures. Biosecurity successes are likely under-recognized because they are difficult to detect and quantify, whereas failures are more evident in the continued establishment of additional non-native species. There are limitations in existing biosecurity systems at global and country scales (for example, inspecting all imports is impossible, no phytosanitary measures are perfect, knownunknowns cannot be regulated against, and noncompliance is an ongoing problem). Biosecurity should be a shared responsibility across countries, governments, stakeholders, and individuals.

On the importance of invasive species niche dynamics in plant conservation management at large and local scale

Predicting the distribution of Invasive alien species (IAS) using species distribution models is promising for conservation planning. To achieve accurate predictions, it is essential to explore species niche dynamics. New approaches are necessary for bringing this analysis to real conservation management needs. Using multi-site comparisons can provide great useful insights to better understand invasion processes. Exploring the fine-scale niche overlap between IAS and native species sharing a location can be a key tool for achieving the implementation of local species conservation actions, which can play a fundamental role in the global management of IAS. This can also increase society’s awareness of the threat of IAS. In this context, here, we explored two key research demands. First, we studied the large-scale niche dynamics of the invasive species Paraserianthes lophantha (Willd.) I.C. Nielsen’s considering different invaded areas. The analysis compared niches of the native range (South Western Australia) with the Australian invaded range (eastern Australia); the native range with the European invaded range, and its full Australian range (native plus invaded range) with the European invaded range. Second, we perform a fine-scale niche overlap analysis at landscape scale in Spain. We studied the niche overlap between P. lophantha and a species with remarkable conservation interest (Quercus lusitanica Lam). All the niche analyses were realized following a well-established ordination (principal component analysis) approach where important methodological aspects were compared and analyzed. Our multi-site study of P. lophantha large-scale niche dynamics detected niche shifts between the Australian ranges demonstrating that the species is labile and may potentially adapt to further European climate conditions and spread its invasive range. Comparative analysis between the European and the full Australian ranges supports that calibrate models including the Australian invasive information is promising to accurate predict P. lophantha European potential distribution. The fine-scale study of niche overlap further explained the potential of this IAS and can be used as a model example of how these local studies can be used to promote the implementation of conservation actions in situ as a complement to large-scale management strategies.

The worldwide networks of spread of recorded alien species

Our ability to predict the spread of alien species is largely based on knowledge of previous invasion dynamics of individual species. However, in view of the large and growing number of alien species, understanding universal spread patterns common among taxa but specific to regions would considerably improve our ability to predict future dynamics of biological invasions. Here, using a comprehensive dataset of years of first record of alien species for four major biological groups (birds, nonmarine fishes, insects, and vascular plants), we applied a network approach to uncover frequent sequential patterns of first recordings of alien species across countries worldwide. Our analysis identified a few countries as consistent early recorders of alien species, with many subsequent records reported from countries in close geographic vicinity. These findings indicate that the spread network of alien species consists of two levels, a backbone of main dispersal hubs, driving intercontinental species movement, and subsequent intracontinental radiative spread in their vicinity. Geographical proximity and climatic similarity were significant predictors of same-species recording among countries. International trade was a significant predictor of the relative timing of species recordings, with countries having higher levels of trade flows consistently recording the species earlier. Targeting the countries that have emerged as hubs for the early spread of alien species may have substantial cascading effects on the global spread network of alien species, significantly reducing biological invasions. Furthermore, using these countries as early-warning system of upcoming invasions may also boost national prevention and invasion preparedness efforts.

The contrasting role of climate variation on the population dynamics of a native and an invasive insect pest

Since 2008, spotted-wing drosophila, Drosophila suzukii, has become a major pest of soft, thin-skinned fruits in the USA, causing significant annual yield losses. Historically, the native blueberry maggot fly, Rhagoletis mendax, has been a key blueberry pest in eastern North America and a driver of insecticide usage. After its invasion in 2011 into New Jersey (USA), D. suzukii has supplanted R. mendax as the main target of insecticide applications in the state. However, the impact of D. suzukii on the native R. mendax has not been documented, particularly in relation to local climate. Historical monitoring data from New Jersey blueberry farms were used to assess the role of climate on R. mendax and D. suzukii populations. Seasonal trap captures of R. mendax adults have decreased after D. suzukii invasion, while D. suzukii trap captures have increased. Similarly, D. suzukii first captures have occurred earlier each year, while R. mendax has been captured later in the growing season. Winter freezing and summer growing degree days were found to significantly correlate with D. suzukii activity. Using downscaled climate simulations, we projected that D. suzukii will arrive in New Jersey blueberry fields up to 5 days earlier on average by 2030 and 2 weeks earlier by 2050 with warming temperatures, exacerbating yield losses and insecticide usage. As regional temperatures are projected to warm and the invasive range continues to expand, we predict the rate of phenological development of the invasive D. suzukii and its impact on native insects to change noticeably, bringing new challenges for pest management strategies.

Economic costs of invasive rodents worldwide: the tip of the iceberg

Background

Rodents are among the most notorious invasive alien species worldwide. These invaders have substantially impacted native ecosystems, food production and storage, local infrastructures, human health and well-being. However, the lack of standardized and understandable estimation of their impacts is a serious barrier to raising societal awareness, and hampers effective management interventions at relevant scales.

Methods

Here, we assessed the economic costs of invasive alien rodents globally in order to help overcome these obstacles. For this purpose, we combined and analysed economic cost data from the InvaCost database-the most up-to-date and comprehensive synthesis of reported invasion costs-and specific complementary searches within and beyond the published literature.

Results

Our conservative analysis showed that reported costs of rodent invasions reached a conservative total of US$ 3.6 billion between 1930 and 2022 (annually US$ 87.5 million between 1980 and 2022), and were significantly increasing through time. The highest cost reported was for muskrat Ondatra zibethicus (US$ 377.5 million), then unspecified Rattus spp. (US$ 327.8 million), followed by Rattus norvegicus specifically (US$ 156.6 million) and Castor canadensis (US$ 150.4 million). Of the total costs, 87% were damage-related, principally impacting agriculture and predominantly reported in Asia (60%), Europe (19%) and North America (9%). Our study evidenced obvious cost underreporting with only 99 documents gathered globally, clear taxonomic gaps, reliability issues for cost assessment, and skewed breakdowns of costs among regions, sectors and contexts. As a consequence, these reported costs represent only a very small fraction of the expected true cost of rodent invasions (e.g., using a less conservative analytic approach would have led to a global amount more than 80-times higher than estimated here).

Conclusions

These findings strongly suggest that available information represents a substantial underestimation of the global costs incurred. We offer recommendations for improving estimates of costs to fill these knowledge gaps including: systematic distinction between native and invasive rodents' impacts; monetizing indirect impacts on human health; and greater integrative and concerted research effort between scientists and stakeholders. Finally, we discuss why and how this approach will stimulate and provide support for proactive and sustainable management strategies in the context of alien rodent invasions, for which biosecurity measures should be amplified globally.

Utilizing volatile organic compounds for early detection of Fusarium circinatum

Fusarium circinatum, a fungal pathogen deadly to many Pinus species, can cause significant economic and ecological losses, especially if it were to become more widely established in Europe. Early detection tools with high-throughput capacity can increase our readiness to implement mitigation actions against new incursions. This study sought to develop a disease detection method based on volatile organic compound (VOC) emissions to detect F. circinatum on different Pinus species. The complete pipeline applied here, entailing gas chromatography-mass spectrometry of VOCs, automated data analysis and machine learning, distinguished diseased from healthy seedlings of Pinus sylvestris and Pinus radiata. In P. radiata, this distinction was possible even before the seedlings became visibly symptomatic, suggesting the possibility for this method to identify latently infected, yet healthy looking plants. Pinus pinea, which is known to be relatively resistant to F. circinatum, remained asymptomatic and showed no changes in VOCs over 28 days. In a separate analysis of in vitro VOCs collected from different species of Fusarium, we showed that even closely related Fusarium spp. can be readily distinguished based on their VOC profiles. The results further substantiate the potential for volatilomics to be used for early disease detection and diagnostic recognition.

An integrated approach for the restoration of Australian temperate grasslands invaded by Nassella trichotoma

Invasive plants are considered to be one of the biggest threats to environmental assets, and once established, they can be immensely difficult to control. Nassella trichotoma is an aggressive, perennial grass species, and is considered to be one of the most economically damaging weeds to grazing systems due to its unpalatability, as well as being one of the leading causes of biodiversity loss in grassland communities. This species produces high density seedbanks that rapidly respond to disturbance events. Despite control programs being developing in Australia since the 1930s, this species is still widespread throughout south-east Australia, indicating that a new management approach is critical to control this Weed of National Significance at the landscape scale. The present study explored the effect of 12 different combinations of herbicide, fire, a second application of herbicide, grazing exclusion, tillage and broadcasting seeds in order to reduce the above and below-ground density of N. trichotoma. A control treatment was also included. The results were assessed using a Hierarchy analysis, whereby treatments of increasing complexity were compared for their efficacy in reducing N. trichotoma cover and seedbank density, while simultaneously increasing the establishment of the broadcast species. Whilst all integrated treatments effectively reduced N. trichotoma's seedbank, the treatments that included fire performed significantly better at simultaneously reducing N. trichotoma and increasing the establishment of broadcasted seeds. Overall, the integration of herbicide, fire and broadcasting native seeds was observed to provide the most economically feasible management strategy for the landscape scale restoration of a degraded temperate grassland dominated by N. trichotoma.

Invasive Species Policy Must Embrace a Changing Climate

With increasing impacts of climate change observed across ecosystems, there is an urgent need to consider climate change in all future environmental policy. But existing policy and management might be slow to respond to this challenge, leading to missed opportunities to incorporate climate change into practice. Furthermore, invasive species threats continue to rise and interact with climate change—exacerbating negative impacts. Enabling natural resource managers and individuals to be proactive about climate-driven invasive species threats creates a win–win for conservation. Recommendations include expanding opportunities for information sharing across borders, supporting proactive screening and regulation of high-risk species on the horizon, and incentivizing individual actions that reduce ecological impacts. In addition, invasive species risk should be considered when crafting climate mitigation and adaptation policy to reduce compounding stressors on ecosystems. As we develop much-needed tools to reduce harm, policy and management must consider the combined threats of invasions and climate change.

Trophic interactions of an invasive gecko in an endemic-rich oceanic island: Insights using DNA metabarcoding

Understanding the trophic interactions of introduced predators is key for evidence-based management of biological invasions. This is particularly important in oceanic islands, where predator-prey networks often include numerous endemic and range-restricted species. Geckos are successful island colonizers and in recent years numerous species have established populations in a wide array of oceanic islands. One such species is the Moorish gecko (Tarentola mauritanica), which has colonized multiple islands across the Mediterranean basin, Caribbean and Macaronesia. The species was first reported in Madeira Island in 1993 and over the last 30 years has colonized most of the islands' southern coast and expanded to the nearby island of Porto Santo. Here, we used DNA metabarcoding to provide the first insights into the diet of this successful colonizer in its introduced range. The species' diet was mainly composed of ground-dwelling arthropods belonging to the families Porcellionidae (Isopoda), Julidae (Diplopoda) and Formicidae (Hymenoptera). The diet richness and composition were not affected by neither sex nor size of adult geckos, instead they both change across populations. However, trophic niche-width differed among size classes, with smaller geckos feeding on a wider range of prey. We identified over 160 different Operational Taxonomic Units in the diet of T. mauritanica, with 21.6% of them belonging to introduced invertebrates and 13.6% to native species. Native prey taxa included the endemic Madeira wall lizard (Teira dugesii), the sole native reptile to Madeira. We also detected several agricultural pests and disease vectors in the diet of this exotic predator, and 19 taxa identified as prey had not yet been recorded to Madeira. Of these, several are serious agricultural pests, highlighting how this introduced gecko can be used as a natural sampler, in particular for the early detection of invasive arthropod pests. This study emphasizes the importance of trophic studies for monitoring the impacts of introduced predators in fragile insular systems.

Soil disturbance and invasion magnify CO2 effects on grassland productivity, reducing diversity

Climate change, disturbance, and plant invasion threaten grassland ecosystems, but their combined and interactive effects are poorly understood. Here, we examine how the combination of disturbance and plant invasion influences the sensitivity of mixed-grass prairie to elevated carbon dioxide (eCO₂ ) and warming. We established subplots of intact prairie and disturbed/invaded prairie within a free-air CO₂ enrichment (to 600 ppmv) by infrared warming (+1.5°C day, 3°C night) experiment and followed plant and soil responses for 5 years. Elevated CO₂ initially led to moderate increases in biomass and plant diversity in both intact and disturbed/invaded prairie, but these effects shifted due to strong eCO₂ responses of the invasive forb Centaurea diffusa. In the final 3 years, biomass responses to eCO₂ in disturbed/invaded prairie were 10 times as large as those in intact prairie (+186% vs. +18%), resulting in reduced rather than increased plant diversity (-17% vs. +10%). At the same time, warming interacted with disturbance/invasion and year, reducing the rate of topsoil carbon recovery following disturbance. The strength of these interactions demonstrates the need to incorporate disturbance into predictions of climate change effects. In contrast to expectations from studies in intact ecosystems, eCO₂ may threaten plant diversity in ecosystems subject to soil disturbance and invasion.

Using Import Data to Predict the Potential of Introduction of Alert Alien Species to South Korea

As globalization progresses, human activities, such as travel and trade, are rapidly increasing beyond national boundaries. It is increasingly recognized that places, such as ports and airports, where trade occurs play a major role as an introduction pathway for alien species. In this study, we focused on evaluating the possibility of introduction of Alert Alien Species (AAS) through trade data among countries. The natural and distribution range of AAS were analyzed along with import data by country. There were large differences between the number of AAS distributed in a country and the import weight of items related to the import of AAS from the country. Fish, which account for 76% of the import weight of AAS, 43 and 40 species of the 84 species of AAS were distributed in US and Russia, respectively. However, the import weight of items related to the import of fish designated as AAS from these countries were extremely low. This finding suggests that trade, which is the main introduction pathway, is not taken into account in the designation of AAS. For future management plans for non-introduced alien species, species with a high possibility of introduction into South Korea through trade should be prioritized using import data.

Genetics reveals shifts in reproductive behaviour of the invasive bird parasite Philornis downsi collected from Darwin’s finch nests

Due to novel or dynamic fluctuations in environmental conditions and resources, host and parasite relationships can be subject to diverse selection pressures that may lead to significant changes during and after invasion of a parasite. Genomic analyses are useful for elucidating evolutionary processes in invasive parasites following their arrival to a new area and host. Philornis downsi (Diptera: Muscidae), the avian vampire fly, was introduced to the Galápagos Islands circa 1964 and has since spread across the archipelago, feeding on the blood of developing nestlings of endemic land birds. Since its discovery, there have been significant changes to the dynamics of P. downsi and its novel hosts, such as shifting mortality rates and changing oviposition behaviour, however no temporal genetic studies have been conducted. We collected P. downsi from nests and traps from a single island population over a 14-year period, and genotyped flies at 469 single nucleotide polymorphisms (SNPs) using restriction-site associated DNA sequencing (RADSeq). Despite significant genetic differentiation (FST) between years, there was no evidence for genetic clustering within or across four sampling years between 2006 and 2020, suggesting a lack of population isolation. Sibship reconstructions from P. downsi collected from 10 Darwin’s finch nests sampled in 2020 showed evidence for shifts in reproductive behaviour compared to a similar genetic analysis conducted in 2004–2006. Compared with this previous study, females mated with fewer males, individual females oviposited fewer offspring per nest, but more unique females oviposited per nest. These findings are important to consider within reproductive control techniques, and have fitness implications for both parasite evolution and host fitness.

The Future of Invasion Science Needs Physiology

Incorporating physiology into models of population dynamics will improve our understanding of how and why invasions succeed and cause ecological impacts, whereas others fail or remain innocuous. Targeting both organismal physiologists and invasion scientists, we detail how physiological processes affect every invasion stage, for both plants and animals, and how physiological data can be better used for studying the spatial dynamics and ecological effects of invasive species. We suggest six steps to quantify the physiological functions related to demography of nonnative species: justifying physiological traits of interest, determining ecologically appropriate time frames, identifying relevant abiotic variables, designing experimental treatments that capture covariation between abiotic variables, measuring physiological responses to these abiotic variables, and fitting statistical models to the data. We also provide brief guidance on approaches to modeling invasions. Finally, we emphasize the benefits of integrating research between communities of physiologists and invasion scientists.

Consistency in impact assessments of invasive species is generally high and depends on protocols and impact types

Impact assessments can help prioritising limited resources for invasive species management. However, their usefulness to provide information for decision-making depends on their repeatability, i.e. the consistency of the estimated impact. Previous studies have provided important insights into the consistency of final scores and rankings. However, due to the criteria to summarise protocol responses into one value (e.g. maximum score observed) or to categorise those final scores into prioritisation levels, the real consistency at the answer level remains poorly understood. Here, we fill this gap by quantifying and comparing the consistency in the scores of protocol questions with inter-rater reliability metrics. We provide an overview of impact assessment consistency and the factors altering it, by evaluating 1,742 impact assessments of 60 terrestrial, freshwater and marine vertebrates, invertebrates and plants conducted with seven protocols applied in Europe (EICAT; EPPO; EPPO prioritisation; GABLIS; GB; GISS; and Harmonia+). Assessments include questions about diverse impact types: environment, biodiversity, native species interactions, hybridisation, economic losses and human health. Overall, the great majority of assessments (67%) showed high consistency; only a small minority (13%) presented low consistency. Consistency of responses did not depend on species identity or the amount of information on their impacts, but partly depended on the impact type evaluated and the protocol used, probably due to linguistic uncertainties (pseudo-R2 = 0.11 and 0.10, respectively). Consistency of responses was highest for questions on ecosystem and human health impacts and lowest for questions regarding biological interactions amongst alien and native species. Regarding protocols, consistency was highest with Harmonia+ and GISS and lowest with EPPO. The presence of few, but very low, consistent assessments indicates that there is room for improvement in the repeatability of assessments. As no single factor explained largely the variance in consistency, low values can rely on multiple factors. We thus endorse previous studies calling for diverse and complementary actions, such as improving protocols and guidelines or consensus assessment to increase impact assessment repeatability. Nevertheless, we conclude that impact assessments were generally highly consistent and, therefore, useful in helping to prioritise resources against the continued relentless rise of invasive species.

Assessing distribution changes of selected native and alien invasive plant species under changing climatic conditions in Nyeri County, Kenya

The role of climate change in enhancing bio-invasions in natural environments needs to be assessed to provide baseline information for effective species management and policy formulations. In this study, potential habitat suitability maps were generated through Ecological Niche Modeling for five problematic alien and native species in current and future climate simulations for the periods 2050s and 2070s under RCP2.6, RCP4.5, and RCP8.5 emission scenarios. Projected current binary suitability maps showed that 67%, 40%, 28%, 68%, and 54% of the total study area ~ 3318 Km2 is suitable for C. decapetala, L. camara, O. stricta, S. didymobotrya and S. campylacanthum species, respectively. Assuming unlimited species dispersal, two of these species, C. decapetala and S. didymobotrya, were observed to have consistent gradual increase in potential habitats and no habitat losses under the three RCPs by the end of the 2050 and 2070 future periods. The highest recorded relative potential habitat increase was observed for O. stricta at ~205% under RCP2.6 and ~223% under RCP8.5. Although L. camara and O. stricta were observed to have habitat losses, the losses will be very low as compared to that of S. campylacanthum. L. camara and O. stricta relative habitat losses were predicted to be between ~1% under RCP2.6 to ~4.5% under RCP8.5 by 2070 while that of S. campylacanthum was between ~50% under RCP2.6 to ~68% under RCP8.5 by the year 2070. From this study we conclude that the target study species are expected to remain a big threat to inhabited areas as well as biodiversity hotspot areas especially in the Mt. Kenya and the Aberdare forest and national park reserves under climate change. The information generated through this study can be used to inform policy on prioritizing management of these species and subsequent determination of their absolute distributions within the area.

Risk of invasiveness of non-native fishes in the South Caucasus biodiversity and geopolitical hotspot

Aquatic invasions are one of the major threats for freshwater ecosystems. However, in developing countries, knowledge of biological invasions, essential for the implementation of appropriate legislation, is often limited if not entirely lacking. In this regard, the identification of potentially invasive non-native species by risk screening, followed by a full risk assessment of the species ranked as higher risk, enables decision-makers to be informed about the extent of the threats posed to the recipient (risk assessment) area. In this study, 32 non-native extant and horizon fish species were screened for their risk of invasiveness under current and predicted climate conditions for the South Caucasus – a biodiversity and geopolitical hotspot that includes the countries of Armenia, Azerbaijan and Georgia. Overall, the number of very high-risk species increased from four (12.5%) under current climate conditions to 12 (37.5%) under predicted climate conditions. The highest-risk species under both conditions included the already established gibel carp Carassius gibelio and topmouth gudgeon Pseudorasbora parva, the locally translocated pikeperch Sander lucioperca and the horizon North African catfish Clarias gariepinus. Under predicted climate conditions, a very high risk of invasiveness was predicted also for the translocated three-spined stickleback Gasterosteus aculeatus and Eurasian perch Perca fluviatilis, for the already established eastern mosquitofish Gambusia holbrooki, ruffe Gymnocephalus cernua, sharpbelly Hemiculter leucisculus and Nile tilapia Orechromis niloticus, and for the horizon pumpkinseed Lepomis gibbosus and largemouth bass Micropterus salmoides. Future research on the non-native species in the South Caucasus should be conducted both country- and region-wide and should account not only for the high biodiversity, but also for the critical geopolitical situation affecting the study area.

More time for aliens? Performance shifts lead to increased activity time budgets propelling invasion success

In the Grinnellian niche concept, the realized niche and potential distribution is characterized as an interplay among the fundamental niche, biotic interactions and geographic accessibility. Climate is one of the main drivers for this concept and is essential to predict a taxon’s distribution. Mechanistic approaches can be useful tools, which use fitness-related aspects like locomotor performance and critical thermal limits to predict the potential distribution of an organism. These mechanistic approaches allow the inclusion key ecological processes like local adaptation and can account for thermal performance traits of different life-history stages. The African Clawed Frog, Xenopus laevis, is a highly invasive species occurring on five continents. The French population is of special interest due to an ongoing expansion for 40 years and a broad base of knowledge. We hypothesize that (1) the French population exhibits increased activity time in the invasive European range that could be devoted to fitness-relevant activity and (2) tadpoles may have less activity time available than adult frogs from the same range. We investigate how thermal performance traits translate into activity time budgets and how local adaptation and differences in the thermal responses of life-history stages may boost the European Xenopus invasion. We use a mechanistic approach based on generalized additive mixed models, where thermal performance curves were used to predict the hours of activity and to compare the potential activity time budgets for two life-history stages of native and invasive populations. Our results show that adult French frogs have more activity time available in Europe compared to South African frogs, which might be an advantage in searching for prey or escaping from predators. However, French tadpoles do not have more activity time in Europe compared to the native South African populations suggesting that tadpoles do not suffer the same strong selective pressure as adult frogs.

Development of a Rapid, Accurate, and On-Site Detection Protocol for Red Imported Fire Ants, Solenopsis invicta (Hymenoptera: Formicidae)

A rapid, accurate, and on-site molecular diagnostic protocol for red imported fire ants (Solenopsis invicta, Si) was developed using loop-mediated isothermal amplification (LAMP) assays. Si11977 (GenBank accession no. MK986826) was confirmed to be a Si-specific gene. Four-primer Si11977-LAMP (4pSi-LAMP) and six-primer Si11977-LAMP (6pSi-LAMP) assays specifically detected Si. The reaction time of 6pSi-LAMP assays was reduced by 5 min compared with 4pSi-LAMP assays. The optimal amount of polymerase and the detection limit for the 6pSi-LAMP assays were 0.1 unit/μL and 5 fg/μL, respectively. In addition, a method for extracting genomic DNA from ant tissues within 2 to 3 min and a protocol for performing on-site LAMP assays using a car heating mug and a LAMP observation box were described. The on-site Si detection protocol used in this study was possible within 30 min from DNA extraction to species identification.

Optimizing management of invasions in an uncertain world using dynamic spatial models

Dispersal drives invasion dynamics of nonnative species and pathogens. Applying knowledge of dispersal to optimize the management of invasions can mean the difference between a failed and a successful control program and dramatically improve the return on investment of control efforts. A common approach to identifying optimal management solutions for invasions is to optimize dynamic spatial models that incorporate dispersal. Optimizing these spatial models can be very challenging because the interaction of time, space, and uncertainty rapidly amplifies the number of dimensions being considered. Addressing such problems requires advances in and the integration of techniques from multiple fields, including ecology, decision analysis, bioeconomics, natural resource management, and optimization. By synthesizing recent advances from these diverse fields, we provide a workflow for applying ecological theory to advance optimal management science and highlight priorities for optimizing the control of invasions. One of the striking gaps we identify is the extremely limited consideration of dispersal uncertainty in optimal management frameworks, even though dispersal estimates are highly uncertain and greatly influence invasion outcomes. In addition, optimization frameworks rarely consider multiple types of uncertainty (we describe five major types) and their interrelationships. Thus, feedbacks from management or other sources that could magnify uncertainty in dispersal are rarely considered. Incorporating uncertainty is crucial for improving transparency in decision risks and identifying optimal management strategies. We discuss gaps and solutions to the challenges of optimization using dynamic spatial models to increase the practical application of these important tools and improve the consistency and robustness of management recommendations for invasions.

Expansion of non-native plant Flaveria bidentis (L.) Kuntze driven by a range of factors leading to patchy distribution patterns

Given the growing concern over the ecological impacts of non-native species, exploring these species' expansion edge and distribution patterns and their driving factors is important for developing suitable management measures. Flaveria bidentis (L.) Kuntze, a non-native plant that was introduced to China in the 1990s, has spread from southern Hebei Province, where it first took root, to the surrounding regions and has become one of the most notorious invasive weeds in northern China. Based on 15 years (2006-2021) of extensive field investigations, the spatial distribution of sampling and occurrence points were mapped in the recently expanded region of F. bidentis' population. Then, nearest neighbor analysis is used to characterize the spatial pattern differences between samplings and occurrences. An exponential decay function was used to elucidate the driving factors contributing to the presence and absence of F. bidentis. Our results demonstrated an effective random sampling setup, a heterogeneous spatial distribution of F. bidentis, and a multi-regional independent aggregation distribution pattern (p < .01). There were significant spatial correlations between the aggregation areas of plant occurrence points and the locations of roads and construction sand distribution centers. These findings suggest that human activities involving major roads and construction sand distribution centers were driving factors contributing to this long-distance dispersal and spatially discontinuous distribution patterns. The presence of these patchy distribution patterns has important implications for ongoing efforts to manage populations of non-native species.

Non-native plant invasion can accelerate global climate change by increasing wetland methane and terrestrial nitrous oxide emissions

Approximately 17% of the land worldwide is considered highly vulnerable to non-native plant invasion, which can dramatically alter nutrient cycles and influence greenhouse gas (GHG) emissions in terrestrial and wetland ecosystems. However, a systematic investigation of the impact of non-native plant invasion on GHG dynamics at a global scale has not yet been conducted, making it impossible to predict the exact biological feedback of non-native plant invasion to global climate change. Here, we compiled 273 paired observational cases from 94 peer-reviewed articles to evaluate the effects of plant invasion on GHG emissions and to identify the associated key drivers. Non-native plant invasion significantly increased methane (CH₄ ) emissions from 129 kg CH₄ ha^-1  year^-1 in natural wetlands to 217 kg CH₄ ha^-1  year^-1 in invaded wetlands. Plant invasion showed a significant tendency to increase CH₄ uptakes from 2.95 to 3.64 kg CH₄ ha^-1  year^-1 in terrestrial ecosystems. Invasive plant species also significantly increased nitrous oxide (N₂ O) emissions in grasslands from an average of 0.76 kg N₂ O ha^-1  year^-1 in native sites to 1.35 kg N₂ O ha^-1  year^-1 but did not affect N₂ O emissions in forests or wetlands. Soil organic carbon, mean annual air temperature (MAT), and nitrogenous deposition (N_DEP) were the key factors responsible for the changes in wetland CH₄ emissions due to plant invasion. The responses of terrestrial CH₄ uptake rates to plant invasion were mainly driven by MAT, soil NH₄ ⁺ , and soil moisture. Soil NO₃ ^- , mean annual precipitation, and N_DEP affected terrestrial N₂ O emissions in response to plant invasion. Our meta-analysis not only sheds light on the stimulatory effects of plant invasion on GHG emissions from wetland and terrestrial ecosystems but also improves our current understanding of the mechanisms underlying the responses of GHG emissions to plant invasion.

An efficient method of evaluating multiple concurrent management actions on invasive populations

Evaluating the efficacy of management actions to control invasive species is crucial for maintaining funding and to provide feedback for the continual improvement of management efforts. However, it is often difficult to assess the efficacy of control methods due to limited resources for monitoring. Managers may view effort on monitoring as effort taken away from performing management actions. We developed a method to estimate invasive species abundance, evaluate management effectiveness, and evaluate population growth over time from a combination of removal activities (e.g., trapping, ground shooting) using only data collected during removal efforts (method of removal, date, location, number of animals removed, and effort). This dynamic approach allows for abundance estimation at discrete time points and the estimation of population growth between removal periods. To test this approach, we simulated over 1 million conditions, including varying the length of the study, the size of the area examined, the number of removal events, the capture rates, and the area impacted by removal efforts. Our estimates were unbiased (within 10% of truth) 81% of the time and were correlated with truth 91% of the time. This method performs well overall and, in particular, at monitoring trends in abundances over time. We applied this method to removal data from Mingo National Wildlife Refuge in Missouri from December 2015 to September 2019, where the management objective is elimination. Populations of feral swine on Mingo NWR have fluctuated over time but showed marked declines in the last 3-6 months of the time series corresponding to increased removal pressure. Our approach allows for the estimation of population growth across time (from both births and immigration) and therefore, provides a target removal rate (above that of the population growth) to ensure the population will decline. In Mingo NWR, the target monthly removal rate is 18% to cause a population decline. Our method provides advancement over traditional removal modeling approaches because it can be applied to evaluate management programs that use a broad range of removal techniques concurrently and whose management effort and spatial coverage vary across time.

Climate Change Effects on Pathogen Emergence: Artificial Intelligence to Translate Big Data for Mitigation

Plant pathology has developed a wide range of concepts and tools for improving plant disease management, including models for understanding and responding to new risks from climate change. Most of these tools can be improved using new advances in artificial intelligence (AI), such as machine learning to integrate massive data sets in predictive models. There is the potential to develop automated analyses of risk that alert decision-makers, from farm managers to national plant protection organizations, to the likely need for action and provide decision support for targeting responses. We review machine-learning applications in plant pathology and synthesize ideas for the next steps to make the most of these tools in digital agriculture. Global projects, such as the proposed global surveillance system for plant disease, will be strengthened by the integration of the wide range of new data, including data from tools like remote sensors, that are used to evaluate the risk ofplant disease. There is exciting potential for the use of AI to strengthen global capacity building as well, from image analysis for disease diagnostics and associated management recommendations on farmers' phones to future training methodologies for plant pathologists that are customized in real-time for management needs in response to the current risks. International cooperation in integrating data and models will help develop the most effective responses to new challenges from climate change.

The magnitude, diversity, and distribution of the economic costs of invasive terrestrial invertebrates worldwide

Invasive alien species (IAS) are a major driver of global biodiversity loss, hampering conservation efforts and disrupting ecosystem functions and services. While accumulating evidence documented ecological impacts of IAS across major geographic regions, habitat types and taxonomic groups, appraisals for economic costs remained relatively sparse. This has hindered effective cost-benefit analyses that inform expenditure on management interventions to prevent, control, and eradicate IAS. Terrestrial invertebrates are a particularly pervasive and damaging group of invaders, with many species compromising primary economic sectors such as forestry, agriculture and health. The present study provides synthesised quantifications of economic costs caused by invasive terrestrial invertebrates on the global scale and across a range of descriptors, using the InvaCost database. Invasive terrestrial invertebrates cost the global economy US$ 712.44 billion over the investigated period (up to 2020), considering only high-reliability source reports. Overall, costs were not equally distributed geographically, with North America (73%) reporting the greatest costs, with far lower costs reported in Europe (7%), Oceania (6%), Africa (5%), Asia (3%), and South America (< 1%). These costs were mostly due to invasive insects (88%) and mostly resulted from direct resource damages and losses (75%), particularly in agriculture and forestry; relatively little (8%) was invested in management. A minority of monetary costs was directly observed (17%). Economic costs displayed an increasing trend with time, with an average annual cost of US$ 11.40 billion since 1960, but as much as US$ 165.01 billion in 2020, but reporting lags reduced costs in recent years. The massive global economic costs of invasive terrestrial invertebrates require urgent consideration and investment by policymakers and managers, in order to prevent and remediate the economic and ecological impacts of these and other IAS groups.

Genomic data is missing for many highly invasive species, restricting our preparedness for escalating incursion rates

Biological invasions drive environmental change, potentially threatening native biodiversity, human health, and global economies. Population genomics is an increasingly popular tool in invasion biology, improving accuracy and providing new insights into the genetic factors that underpin invasion success compared to research based on a small number of genetic loci. We examine the extent to which population genomic resources, including reference genomes, have been used or are available for invasive species research. We find that 82% of species on the International Union for Conservation of Nature “100 Worst Invasive Alien Species” list have been studied using some form of population genetic data, but just 32% of these species have been studied using population genomic data. Further, 55% of the list’s species lack a reference genome. With incursion rates escalating globally, understanding how genome-driven processes facilitate invasion is critical, but despite a promising trend of increasing uptake, “invasion genomics” is still in its infancy. We discuss how population genomic data can enhance our understanding of biological invasion and inform proactive detection and management of invasive species, and we call for more research that specifically targets this area.

Building a synthesis of economic costs of biological invasions in New Zealand

Biological invasions are a major component of anthropogenic environmental change, incurring substantial economic costs across all sectors of society and ecosystems. There have been recent syntheses of costs for a number of countries using the newly compiled InvaCost database, but New Zealand-a country renowned for its approach to invasive species management-has so far not been examined. Here we analyse reported economic damage and management costs incurred by biological invasions in New Zealand from 1968 to 2020. In total, US$69 billion (NZ$97 billion) is currently reported over this ∼50-year period, with approximately US$9 billion of this considered highly reliable, observed (c.f. projected) costs. Most (82%) of these observed economic costs are associated with damage, with comparatively little invested in management (18%). Reported costs are increasing over time, with damage averaging US$120 million per year and exceeding management expenditure in all decades. Where specified, most reported costs are from terrestrial plants and animals, with damages principally borne by primary industries such as agriculture and forestry. Management costs are more often associated with interventions by authorities and stakeholders. Relative to other countries present in the InvaCost database, New Zealand was found to spend considerably more than expected from its Gross Domestic Product on pre- and post-invasion management costs. However, some known ecologically (c.f. economically) impactful invasive species are notably absent from estimated damage costs, and management costs are not reported for a number of game animals and agricultural pathogens. Given these gaps for known and potentially damaging invaders, we urge improved cost reporting at the national scale, including improving public accessibility through increased access and digitisation of records, particularly in overlooked socioeconomic sectors and habitats. This also further highlights the importance of investment in management to curtail future damages across all sectors.

More than half of data deficient species predicted to be threatened by extinction

The IUCN Red List of Threatened Species is essential for practical and theoretical efforts to protect biodiversity. However, species classified as “Data Deficient” (DD) regularly mislead practitioners due to their uncertain extinction risk. Here we present machine learning-derived probabilities of being threatened by extinction for 7699 DD species, comprising 17% of the entire IUCN spatial datasets. Our predictions suggest that DD species as a group may in fact be more threatened than data-sufficient species. We found that 85% of DD amphibians are likely to be threatened by extinction, as well as more than half of DD species in many other taxonomic groups, such as mammals and reptiles. Consequently, our predictions indicate that, amongst others, the conservation relevance of biodiversity hotspots in South America may be boosted by up to 20% if DD species were acknowledged. The predicted probabilities for DD species are highly variable across taxa and regions, implying current Red List-derived indices and priorities may be biased.

Data Deficient species are more likely to be at extinction risk than previously thought across multiple taxonomic groups.

Functional traits underlying performance variations in the overwintering of the cosmopolitan invasive plant water hyacinth (Eichhornia crassipes) under climate warming and water drawdown

Reports of the Intergovernmental Panel on Climate Change (IPCC) indicate that temperature rise is still the general trend of the global climate in the 21st century. Invasive species may benefit from the increase in temperature, as climate can be viewed as a resource, and the increase in the available resources favors the invasibility of invasive species. This study aimed to assess the overwintering growth of the cosmopolitan invasive plant water hyacinth (Eichhornia crassipes) at its northern boundary. Using E. crassipes as a model plant, a cross-year mesocosm experiment was conducted to determine 17 plant functional traits, including growth, morphological, root topological, photosynthetic, and stoichiometric traits, under climate warming (ambient, temperature rises of 1.5°C and 3.0°C), and water drawdown or water withdrawal (water depths of 1, 10, and 20 cm) treatments. The overwintering growth of E. crassipes was facilitated by climate warming and proper water drawdown, and climate warming played a leading role. A temperature rises of 3.0°C and a water depth of 10 cm were the most suitable conditions for the overwintering and rooting behavior of the plant. Controlling the temperature to within 1.5°C, an ambitious goal for China, still facilitated the overwintering of E. crassipes. With climate warming, the plant can overwinter successfully, which possibly assists it in producing and spreading new ramets in the vernal flood season. The new rooting behavior induced by ambient low temperature may be viewed as a unique growth adaptation strategy for a niche change, as it helps these plants invade empty niches left by dead free-floating plants on the water surface following winter freezes. With continued global warming, the distribution of the plant may expand northward, and eradication of the plant during the winter water drawdown period may be a more effective strategy.

Capacity of countries to reduce biological invasions

The extent and impacts of biological invasions on biodiversity are largely shaped by an array of socio-economic and environmental factors, which exhibit high variation among countries. Yet, a global analysis of how these factors vary across countries is currently lacking. Here, we investigate how five broad, country-specific socio-economic and environmental indices (Governance, Trade, Environmental Performance, Lifestyle and Education, Innovation) explain country-level (1) established alien species (EAS) richness of eight taxonomic groups, and (2) proactive or reactive capacity to prevent and manage biological invasions and their impacts. These indices underpin many aspects of the invasion process, including the introduction, establishment, spread and management of alien species. They are also general enough to enable a global comparison across countries, and are therefore essential for defining future scenarios for biological invasions. Models including Trade, Governance, Lifestyle and Education, or a combination of these, best explained EAS richness across taxonomic groups and national proactive or reactive capacity. Historical (1996 or averaged over 1996-2015) levels of Governance and Trade better explained both EAS richness and the capacity of countries to manage invasions than more recent (2015) levels, revealing a historical legacy with important implications for the future of biological invasions. Using Governance and Trade to define a two-dimensional socio-economic space in which the position of a country captures its capacity to address issues of biological invasions, we identified four main clusters of countries in 2015. Most countries had an increase in Trade over the past 25 years, but trajectories were more geographically heterogeneous for Governance. Declines in levels of Governance are concerning as they may be responsible for larger levels of invasions in the future. By identifying the factors influencing EAS richness and the regions most susceptible to changes in these factors, our results provide novel insights to integrate biological invasions into scenarios of biodiversity change to better inform decision-making for policy and the management of biological invasions.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11625-022-01166-3.

Climate change-induced invasion risk of ecosystem disturbing alien plant species: An evaluation using species distribution modeling

Species distribution modeling is widely used for evaluating invasion risk, and for prioritizing areas for the control and management of invasive species. However, selecting a modeling tool that accurately predicts species invasion risk requires a systematic approach. In this study, five species distribution models (SDMs), namely, artificial neural network (ANN), generalized linear model (GLM), multivariate adaptive regression splines (MARS), maximum entropy (MaxEnt), and random forest (RF), were performed and evaluated their model performance using the mean value of area under the curve (AUC), true skill statistics (TSS), and Kappa scores of 12 ecosystem disturbing alien plant species (EDAPS). The mean evaluation metric scores were highest in RF (AUC = 0.924 ± 0.058, TSS = 0.789 ± 0.109, Kappa = 0.671 ± 0.096, n = 12) and lowest in ANN. The ANOVA of AUC, TSS, and Kappa metrics revealed the RF model was significantly different from other SDMs and was therefore selected as the relatively best model. The potential distribution area and invasion risk for each EDAPS were quantified. Under the current climate conditions of South Korea, the average potential distribution area of EDAPS was estimated to be 13,062 km2. However, in future climate change scenarios, the average percentage change of EDAPS distribution relative to the current climate was predicted to be increased over 219.93%. Furthermore, under the current climate, 0.16% of the area of the country was estimated to be under a very high risk of invasion, but this would increase to 60.43% by 2070. Invasion risk under the current climate conditions was highest in the northwestern, southern, and southeastern regions, and in densely populated cities, such as Seoul, Busan, and Daegu. By 2070, invasion risk was predicted to expand across the whole country except in the northeastern region. These results suggested that climate change induced the risk of EDAPS invasiveness, and SDMs could be valuable tools for alien and invasive plant species risk assessment.

Scanning the horizon for invasive plant threats using a data-driven approach

Early detection and eradication of invasive plants are more cost-effective than managing well-established invasive plant populations and their impacts. However, there is high uncertainty around which taxa are likely to become invasive in a given area. Horizon scanning that combines a data-driven approach with rapid risk assessment and consensus building among experts can help identify invasion threats. We performed a horizon scan of potential invasive plant threats to Florida, USA—a state with a high influx of introduced species, conditions that are generally favorable for plant establishment, and a history of negative impacts from invasive plants. We began with an initial list of 2128 non-native plant taxa that are known invaders or crop pests. We built on previous invasive species horizon scans by developing data-based criteria to prioritize 100 taxa for rapid risk assessment. The semi-automated prioritization process included selecting taxa “on the horizon” (i.e., not yet in the target location and not on a noxious weed list) with climate matching, naturalization history, “weediness” record, and global commonness. We derived overall invasion risk scores with rapid risk assessment by evaluating the likelihood of each of the taxa arriving, establishing, and having an impact in Florida. Then, following a consensus-building discussion, we identified six plant taxa as high risk, with overall risk scores ranging from 75 to 100 out of a possible 125. The six taxa are globally distributed, easily transported to new areas, found in regions with climates similar to Florida’s, and can impact native plant communities, human health, or agriculture. Finally, we evaluated our initial and final lists for potential biases. Assessors tended to assign higher risk scores to taxa that had more available information. In addition, we identified biases towards four plant families and certain geographical regions of origin. Our horizon scan approach identified taxa conforming to metrics of high invasion risk and used a methodology refined for plants that can be applied to other locations.

Geographical Distribution of Three Forest Invasive Beetle Species in Romania

Ips duplicatus (Sahlberg, 1836), Xylosandrus germanus (Blandford, 1894) and Neoclytus acuminatus (Fabricius, 1775) are invasive species reported in Romania, but their current distribution is poorly known. The research aim was to provide new information on this issue. A survey was conducted over the period 2015–2017 in 82 locations, using flight-interception traps and bottle traps, baited with different attractants. Data obtained in our other unpublished studies were also taken into account. A total of 35,136 I. duplicatus beetles were collected in 30 survey locations. The highest captures were in the log yards of some factories processing logs of Norway spruce (Picea abies (L.) H. Karst.). Considering all known records so far, most of these are in the eastern part of Romania, where an outbreak took place during the years 2005–2014, mainly in spruce stands growing outside their natural range. During the survey, 4259 specimens of X. germanus were collected in 35 locations, but in our other studies the species was found in 13 additional places. It was collected at altitudes of 18–1200 m, and the largest catches were from beech stands, growing at 450–950 m. N. acuminatus was found in only six locations, in the western and southern parts of the country, at low altitudes, in tree stands composed of Fraxinus excelsior L., Quercus spp. and other broadleaf species, as well as in broadleaf log yards. The results suggest that I. duplicatus is established in most parts of the Norway spruce’s range, X. germanus is still spreading in the country, with some areas having quite high populations, while N. acuminatus is present only in the warmest regions of the country.

The Bugs in the Bags: The Risk Associated with the Introduction of Small Quantities of Fruit and Plants by Airline Passengers

Simple Summary

This study was carried out with the aim of emphasizing the importance of checking the plant material that can be imported in the baggage of airline passengers. Travelers are often unaware of the regulations in place and of the risks connected with such importation. The risk of the introduction of harmful organisms correlated with this pathway is yet not well studied and its frequency is underestimated. The results of the research underline the need for continuous checks at entry points and the establishment of a specialized position for inspections.

Abstract

Among European countries, Italy is the most exposed to the risk of biological invasions, principally for its numerous entry points (ports and airports) and for climatic conditions favorable for the acclimatization of several invasive species. Here it was assessed that the greatest threats to our agro-ecosystems come mainly from the passenger baggage in which a variety of fruits and vegetables are carried. From 2016 to 2021, large quantities of plant products were found in the luggage of passengers travelling from outside the EU and seized at the BCPs (border control posts) in the Campania region. Inspections and the following laboratory analyses were conducted on the plant material to assess the presence of exotic pests. Inspections led to several non-native species being recorded, and among the intercepted organisms, some should be considered “alarming”, such as Bactrocera dorsalis, Anastrepha obliqua, and Leucinodes africensis. Despite a well-organized border inspection system, travelers transporting infested material unknowingly contribute to increasing the risk of the introduction of exotic species. Given the current situation, it is necessary to impose stricter controls and greater attention, ensuring compliance with the requirements of the new phytosanitary regulations by the actors involved in the transport of plant material. Finally, it is essential to improve awareness through a phytosanitary campaign on plant health risks, especially for people wishing to transport fruits and vegetables in their luggage.

Late quaternary biotic homogenization of North American mammalian faunas

Biotic homogenization—increasing similarity of species composition among ecological communities—has been linked to anthropogenic processes operating over the last century. Fossil evidence, however, suggests that humans have had impacts on ecosystems for millennia. We quantify biotic homogenization of North American mammalian assemblages during the late Pleistocene through Holocene (~30,000 ybp to recent), a timespan encompassing increased evidence of humans on the landscape (~20,000–14,000 ybp). From ~10,000 ybp to recent, assemblages became significantly more homogenous (>100% increase in Jaccard similarity), a pattern that cannot be explained by changes in fossil record sampling. Homogenization was most pronounced among mammals larger than 1 kg and occurred in two phases. The first followed the megafaunal extinction at ~10,000 ybp. The second, more rapid phase began during human population growth and early agricultural intensification (~2,000–1,000 ybp). We show that North American ecosystems were homogenizing for millennia, extending human impacts back ~10,000 years.

Biotic homogenization, which is increased similarity in the composition of species among communities, is rising due to human activities. Using North American mammal fossil records from the past 30,000 years, this study shows that this phenomenon is ancient, beginning between 12,000 and 10,000 years ago with the extinction of the mammal megafauna.

The Impact of Climate Change on Potential Invasion Risk of Oryctes monoceros Worldwide

As a significant threat to agriculture, pests have caused a great disservice to crop production and food security. Understanding the mechanisms of pests’ outbreaks and invasion is critical in giving sound suggestions on their control and prevention strategies. The African rhinoceros beetle, Oryctes monoceros (Olivier), as the most damaging pest of palms, banana, sugarcane, and pineapple, severely threatens their production due to its ability to kill both young and matured hosts. Analyzing the effect of climate change on major parameters of O. monoceros life history has been an important issue recently, given its sensitivity to thermal conditions. However, information on how climate change alters geographical distribution of O. monoceros is poorly understood. By combining environmental variables and occurrence records, we were able to assess environmental risk factors for O. monoceros and create risk maps for the pest using the Boosted Regression Tree model. Our results significance of environmental variables showed that the annual temperature variation (39.45%), seasonality of temperature (23.00%), the isothermality (18.76%), precipitation of the hottest quarter months (6.07%), average variation of day time temperature (3.27%), were relatively important environmental factors that affected the distribution O. monoceros. We also found that the projected potential distributions of the pest’s habitats in all future global warming scenarios exceeded its present known distribution. The model predicts that habitat suitability for O. monoceros is predominantly concentrated along Africa’s west and east coastlines, Asia’s south coasts, South America’s north and east coasts, and a few locations spread over North America’s southern coasts and coastal regions. These outputs provide a solid theoretical foundation for O. monoceros risk evaluations and control.

Impact of COVID-19 lockdown on aquatic environment and fishing community: Boon or bane?

COVID-19 pandemic is a serious threat for mankind having an extensive socio-economic impact. However, it is considered as an unfortunate event with some positive environmental effects where nature is retrieving itself. The water quality index in different places of the world was reported to be improved during the lockdown, which in turn whipped up the regenerative process of fishes, sea turtles, marine mammals, and aquatic birds. Additionally, ecologically sensitive areas such as mangroves and coral reefs were also seen rejuvenating during COVID-19 seal off. But these favourable implications are temporary as there is an unexpected surge in plastic waste generation in the form of PPE kits, face masks, gloves, and other healthcare equipment. Moreover, the outbreak of the pandemic resulted in the complete closure of fishing activities, decline in fish catch, market disruption, and change in consumer preference. To address these multidimensional effects of the COVID-19 pandemic, government organizations, NGOs, and other concerned authorities should extend their support to amplify the positive impacts of the lockdown and reduce the subsequent pollution level while encouraging the fisheries sector.