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This study examines the spectral characteristics of two invasive plant species, Amur honeysuckle (Lonicera maackii) and Callery 'Bradford' pear (Pyrus calleryana Decne), in central Kentucky's recreational areas. Using a combination of spectrometer, satellite (National Agriculture Imagery Program (NAIP)) and unmanned aerial vehicle (UAV) data, this study investigated the correlation between leaf locations and normalized difference vegetation index (NDVI), as well as the impact of terrain features on vegetation indices. Significant variations in NDVI and normalized difference red-edge (NDRE) index values across study areas and leaf positions were observed. Terrain attributes, particularly slope and aspect direction, significantly influenced vegetative indices in one study site. Weak to moderate correlations were found between the spectrometer and UAV-derived NDVI and NDRE values. Additionally, the study highlighted the feasibility of upscaling UAV data for NAIP imagery comparison, reaffirming the superior accuracy of UAV imagery in assessing vegetation health. This integration of remote sensing techniques offers valuable insights into the spectral characteristics of invasive plants, essential for their effective mapping and management. [ABSTRACT FROM AUTHOR]

Background: Certain mosquitoes are known as dominant vectors worldwide, and transmit infectious diseases. The expansion of mosquito habitats due to climate change and increased human activities poses a significant health threat by facilitating the spread of various non-native infectious diseases. This study focused on the detection of the Southeast Asian mosquito species, Aedes (Mucidus) laniger (Wiedemann, 1820) on Jeju Island, the southernmost region of the Republic of Korea (ROK), highlighting the potential risks associated with the spread of vector-borne diseases, particularly emphasizing the elevated likelihood of invasion by Southeast Asian mosquitoes. Methods: Field surveys were conducted in August 2023 on Jeju Island. Adult mosquitoes were collected using BG-sentinel traps and identified to the species level using taxonomic keys. Morphological and molecular analyses were employed to confirm species designations. Molecular data, including mitochondrial and nuclear genes, were used for phylogenetic analysis, which was performed to compare and identify among recorded subgenera in ROK. Species distribution modeling for Ae. laniger was performed to predict potential habitats using R package 'BIOMOD2'. Results: The two specimens of Ae. laniger were collected for the first time on Jeju Island. Morphological and molecular analyses confirmed the identity of this species within the subgenus Mucidus and validated the first record of this species in the ROK. We employed a simple multigene phylogenetic analysis to confirm a new mosquito record at the genus and subgenus levels, finally validating the consistency between morphological identification and molecular phylogenetic outcomes. Furthermore, we have updated the taxonomic keys for the genus Aedes in the ROK, and revised mosquito lists for Jeju Island, incorporating the inclusion of Ae. laniger. On the basis of species distribution modeling, the area of suitable habitat for Ae. laniger is expected to expand due to climate change, but this change did not appear to be meaningful in East Asia. Conclusions: This case offers the first report of the Southeast Asian mosquito, Ae. laniger, in the ROK. The detection of this species on Jeju Island suggests the potential establishment of a breeding population their habitat and raises concerns about further expansion into the Korean Peninsula. Considering the annual occurrence of mosquito-borne disease cases in the Southeast Asia, it is essential to conduct monitoring not only in Jeju Island, where Ae. laniger has been identified, but also across the entire Korean Peninsula. [ABSTRACT FROM AUTHOR]

Monitoring and managing the global spread of invasive and alien species requires accurate spatiotemporal records of species presence and information about the biological characteristics of species of interest including life cycle information, biotic and abiotic constraints and pathways of spread. The Global Invasive and Alien Traits And Records (GIATAR) dataset provides consolidated dated records of invasive and alien presence at the country-scale combined with a suite of biological information about pests of interest in a standardized, machine-readable format. We provide dated presence records for 46,666 alien taxa in 249 countries constituting 827,300 country-taxon pairs in locations where the taxon's invasive status is either alien, invasive, or unknown, joined with additional biological information for thousands of taxa. GIATAR is designed to be quickly updateable with future data and easy to integrate into ongoing research on global patterns of alien species movement using scripts provided to query and analyze data. GIATAR provides crucial data needed for researchers and policymakers to compare global invasion trends across a wide range of taxa. [ABSTRACT FROM AUTHOR]

Freshwater turtles are often used as terrarium pets, especially juveniles of exotic species. At the adult stage they are often released by their owners into the wild despite their high invasion potential. In Europe these thermophilic potentially invasive alien species occupy the habitats of the native European pond turtle Emys orbicularis (Linnaeus, 1758), with new records from the wild being made specifically in Eastern Europe (Latvia and Ukraine) during recent decades. Assessing the potential of alien freshwater turtles to establish in new territories is of great concern for preventing invasion risks while preserving native biodiversity in the present context of climate change. We explored this issue by identifying the present and future (by 2050) suitable habitats of the European pond turtle and several potentially invasive alien species of freshwater turtle already settled in Europe, using a geographic information system (GIS) modelling approach based on datasets from CliMond for climate, Near-global environmental information (NGEI) for freshwater ecosystems (EarthEnv) and Maxent modelling using open-access databases, data from the literature and original field data. Modelling was performed for seven species of alien freshwater turtles occurring from the extreme northern to southern borders of the European range of E. orbicularis: the pond slider Trachemys scripta (Thunberg and Schoepff, 1792), the river cooter Pseudemys concinna (Le Conte, 1830), the Florida red-bellied cooter Pseudemys nelsoni (Carr, 1938), the false map turtle Graptemys pseudogeographica (Gray, 1831), the Chinese softshell turtle Pelodiscus sinensis (Wiegmann, 1835), the Caspian turtle Mauremys caspica (Gmelin, 1774) and the Balkan terrapin Mauremys rivulata (Valenciennes, 1833). In Ukraine, the most Eastern limit of E. orbicularis distribution, were previously reported northern American originated T. scripta, M. rivulata, M. caspica, whereas in Latvia, Emys' most northern limit, were additionally reported P. concinna, P. nelsoni, G. pseudogeographica and Asia originated P. sinensis. The resulting Species Distribution Models (SDM) were of excellent performance (AUC > 0.8). Of these alien species, the most potentially successful in terms of range expansion throughout Europe were T. scripta (34.3% of potential range expansion), G. pseudogeographica (24.1%), and M. caspica (8.9%) and M. rivulata (4.3%) mainly in Eastern Europe, especially in the south of Ukraine (Odesa, Kherson, Zaporizhzhia regions, and Crimean Peninsula). Correlation between the built SDMs for the native E. orbicularis and the invasive alien T. scripta was reliably high, confirming the highly likely competition between these two species in places they cooccur. Moreover, a Multiple Regression Analysis revealed that by 2050, in most of Europe (from the western countries to Ukraine), the territory overlap between E. orbicularis and potentially invasive alien species of freshwater turtles will increase by 1.2 times, confirming higher competition in the future. Importantly, by 2050, Eastern Europe and Ukraine are predicted to be the areas with most suitable habitats for the European pond turtle yet with most limited overlap with the invasive alien species. We conclude that Eastern Europe and Ukraine are the most relevant priority conservation areas for the European pond turtle where it is now necessary to take protective measures to ensure safe habitat for this native species on the long-term. [ABSTRACT FROM AUTHOR]

In order to discharge ballast in waters of the USA and Member States of the IMO, a vessel must comply with ballast water discharge standards (BWDS). In most cases, this involves use of a Type-Approved ballast water management system (BWMS). Although rigorous efficacy testing is required to gain Type-Approval status, there are currently no requirements for regular compliance checks after a BWMS has been commissioned. Routine compliance checks, to enumerate organisms in treated discharges, are currently the only way to know if a system is meeting a BWDS. This policy brief has two objectives: 1) Highlight the importance of routine collection and analysis of treated ballast water discharges, and 2) Present technical considerations to perform compliance assessments, highlighting good practices for sample collection and analysis and advising of potential obstacles. These assessments are necessary to inhibit the spread of non-indigenous species. [ABSTRACT FROM AUTHOR]

Invasive alien species drive extensive ecological changes and cause unexpected risks worldwide. Perceptive germination requirements and the growth function of invasive species are crucial for understanding their invasion and subsequent dissemination in various environmental conditions. Therefore, the germination response of invasive Conyza bonariensis, Parthenium hysterophorus, and Bidens pilosa of Asteraceae family were examined under alternating temperature regimes and some environmental factors. The prevailing germination ability occurs highest at moderate-temperature regimes at 20/30°C attained by 94.83% (C. bonariensis) and at 20/25 SS by 96.28% (P. hysterophorus) and high-temperature regimes at 25/30°C reached 92.94% (B. pilosa) respectively. The half germination percentage (G50) was -0.406 MPa and 2878.35 ppm (B. pilosa), -0.579 MPa and 2490.9 ppm (C. bonariensis), and—0.32 MPa and 2490.8 ppm (P. hysterophorus) affected by osmotic pressure and salt stress (NaCl) respectively. The highest growth plasticity characteristics were identified in total dry mass attained at 0.968 (C. bonariensis), 0.985 (B. pilosa) and 0.957 (P. hysterophorus) respectively. The relative growth, net assimilation and plasticity index appeared higher in both B. pilosa, and C. bonariensis than P. hysterophorus in the invaded area. In conclusion, germination and growth traits are precisely functional factors that correlate to invasion success under stressed conditions, and zones, and also lead to successful control plans for invasive species and ecological protection. [ABSTRACT FROM AUTHOR]

Dams commonly restrict fish movements in large rivers but can also help curtail the spread of invasive species, such as invasive bigheaded carps (Hypophthalmichthys spp). To determine how dams in the upper Mississippi River (UMR) affect large-scale invasive and native fish migrations, we tracked American paddlefish (Polyodon spathula) and bigheaded carp across > 600 river km (rkm) and 16 navigation locks and dams (LD) of the UMR during 2 years with contrasting water levels. In 2022, a low-water year, both native paddlefish and invasive bigheaded carp had low passage rates (4% and 0.6% respectively) through LD15, a movement bottleneck being studied for invasive carp control. In contrast, flooding in 2023 led to open-river conditions across multiple dams simultaneously, allowing 53% of paddlefish and 46% of bigheaded carp detected in Pool 16 to move upstream through LD15. Bigheaded carp passed upstream through LD15 rapidly (μ = 32 rkm per day) a maximum of 381 rkm, whereas paddlefish moved an average of 9 upstream rkm per day (maximum of 337 rkm). Our results can inform managers examining trade-offs between actions that enhance native fish passage or deter movements of invasive species. This understanding is critical because current climate change models project increases in flooding events like that observed during 2023. [ABSTRACT FROM AUTHOR]

Nestmate recognition in ants is regulated through the detection of cuticular hydrocarbons by odorant receptors (ORs) in the antennae. These ORs are crucial for maintaining colony cohesion that allows invasive ant species to dominate colonized environments. In the invasive Argentine ant, Linepithema humile, ORs regulating nestmate recognition are thought to be present in a clade of nine-exon odorant receptors, but the identity of the specific genes remains unknown. We sought to narrow down the list of candidate genes using transcriptomics and phylostratigraphy. Comparative transcriptomic analyses were conducted on the antennae, head, thorax, and legs of Argentine ant workers. We have identified a set of twenty-one nine-exon odorant receptors enriched in the antennae compared to the other tissues, allowing for downstream verification of whether they can detect Argentine ant cuticular hydrocarbons. Further investigation of these ORs could allow us to further understand the mechanisms underlying nestmate recognition and colony cohesion in ants. [ABSTRACT FROM AUTHOR]

Trapping the Asian hornet remains a viable alternative to monitor its presence, dispersion, and ecological niche. With the objective of evaluating the effectiveness of baits and traps, an Asian hornet (Vespa velutina) capture trial was conducted using combinations of artisanal and commercial baits and traps. The second objective was to explore the relationship between the species' dispersal patterns and the influence of human, geography, climate, and vegetation factors, to identify the preferred conditions for its colonization. We identified beekeepers in the Alto Minho region of Northern Portugal, where the different combinations of baits and traps were placed. The traps were monitored from February to September 2023, and the captures were counted. The temporal variation of the captures showed a first peak at the beginning of April, corresponding to primary workers. In September, when the trial was halted, the second peak, corresponding to secondary workers, had not yet been reached. The peaks of captures were used to fit models to allow the characterisation of their ecological niche. Statistical analysis of the captures revealed no significant differences. It was concluded that there is no advantage in using the commercial devices and baits tested. The ecological niche where the higher number of captures is observed is characterised by an abundance of vegetation, humidity, and higher temperatures. Elevation and slope also favour the presence of the Asian hornet. [ABSTRACT FROM AUTHOR]

In this study we focused on the need to fill a knowledge gap among Italian botanical studies namely that of ornamental species census. In particular, we addressed one of the regions in southern Italy with less knowledge in the field of such studies and with an obvious presence of non-native species. A widespread census of the Apulian territory was carried out between 2021 and 2024 in both urban and suburban areas including street trees, parks, and private and historic gardens. The inventory of ornamental trees, shrubs, and succulents of Apulia (southern Italy) was carried out in six provinces, i.e., Bari, Barletta-Andria-Trani, Brindisi, Foggia, Lecce, and Taranto. The checklist comprises 287 taxa (including 265 species, 6 varieties, 5 subspecies, and 11 forms) included in 179 genera belonging to 78 families. We evaluated the number of taxa per families and genera, the presence of each taxa in the provinces of Apulia, the number of taxa per occurrence status, growth forms, geographical origin, and the number of native and alien taxa and also the artificial hybrids. Remarks of the most significant taxa and evaluation of geographical distribution in Italy were also taken into consideration. A large number of surveyed taxa (51.74%) are comprised in the list reported in the recent study on allochthonous vascular flora in Italy with a marked prevalence of Neophyte Casual Alien and Neophyte Naturalized Alien species. [ABSTRACT FROM AUTHOR]

Invasive alien plants (IAPs) pose a significant threat to island biodiversity and severely impact ecosystems. Understanding the species–area relationship and environmental determinants of growth forms for IAP species on subtropical islands is crucial for establishing an IAP's early warning mechanism, enhancing island ecological management, and protecting the ecosystems of Fujian and other subtropical islands. The study identified significant species–area relationships for IAPs and different life-form plants (trees, shrubs, and herbs), with slopes of 0.27, 0.16, 0.15, and 0.24, respectively. The small island effect does not apply to all species. Isolation has little effect on species richness, and the IAPs on Fujian islands do not conform to the isolation effect in island biogeography. Landscape factors are the main determinants of IAPs and different life-form species richness, with area, shape index, and perimeter–area ratio being the three primary landscape factors. These environmental factors are closely related to habitat heterogeneity. Besides landscape factors, different life forms respond differently to environmental factors. Climate drives the species richness distribution of shrubs and herbs, while trees are mainly influenced by human activities. Overall, landscape, human disturbance, and climate jointly drive the distribution of IAPs, with landscape factors being the most significant. [ABSTRACT FROM AUTHOR]

The Brazilian pepper tree (Schinus terebinthifolius) is an invasive species that requires significant disturbance to eradicate. Previous studies have identified associations between the Brazilian pepper tree and ectomycorrhizal fungi (EMF). However, limited research has explored the connection between disturbance from removal and the effect on EMF. This study investigated the sensitivity of EMF and the broader fungal community to the full and selective removal of the Brazilian pepper tree. During the selective removal of Brazilian pepper tree, we examined the mycorrhizal community of the Arroyo willow (Salix lasiolepis) to assess the influence of the restoration disturbance on native species. We used ITS2 sequencing to identify the EMF present during the restoration. Our expectation was that both removal efforts would reduce the presence of EMF. Contrary to our predictions, full removal increased EMF richness and relative abundance in the soil. As anticipated, selective removal reduced the richness and relative abundance of EMF associated with soil. Selective removal led to a decrease in the richness of EMF in arroyo willow roots with no effect on relative abundance. Moreover, fungal community composition in soil and roots shifted significantly during selective and full removal. However, the community composition of EMF, specifically, remained constant across treatment types. During full removal efforts, the application of organic soil amendments may have contributed to the increase in the diversity and relative abundance of EMF. Selective removal will require additional measures, such as soil amendments, to curtail the loss of EMF. [ABSTRACT FROM AUTHOR]

Santalum album is a hemiparasitic evergreen tree known for its heartwood oil, widely used in the cosmetics and aromatherapy industry. Overexploitation in the past few decades has led to the classification of this species as Vulnerable on the IUCN Red List of Threatened Species. Drupes of S. album are single-seeded and usually monoembryonic in nature, producing normal seedlings. However, in a previous study, we also observed some polyembryonic seeds. In this news article we share our polyembryony findings from Marayoor population as well as the growth and survival of seedlings which emerged from polyembryonic seeds. We found that less than 1% of the seeds in Marayoor population exhibited polyembryony (duplets). The general trend was that one radicle emerged 2-3 days earlier than the other and grew faster and healthier compared to the radicle from monoembryonic seeds. The second (smaller) seedling from polyembryonic seeds began to degenerate if not separated, but it survived well (albeit with low growth potential) once transplanted into a separate polybag. In S. album, polyembryony does not seems to be an essential ecological competitive strategy, unlike in several invasive species. For mass-scale seedling production of this vulnerable species, we recommend separating twin seedlings soon after their emergence for a better survival rate. [ABSTRACT FROM AUTHOR]

Proper management of woody ecosystems is fundamental for human livelihoods and biodiversity conservation. Strip cutting or selective harvesting are proposed as sustainable alternatives to clear-cut logging. However, their impacts are not fully understood, especially when we consider the harvesting intensity levels and the invasibility of an ecosystem by nonnative tree species. In this study we analyzed the impacts of different harvesting intensity levels on the establishment after 2 years of nonnative and native tree species. We conducted this study in a mixed forest dominated by Nothofagus antarctica, where we applied four strip harvesting levels: 0% (control), 30%, 50% and 70% percentage of vegetation removal in eight plots (1417.5 m2 each plot) Inside those plots, we had a total of 24 subplots (3 sites × 8 plots) were we sowed seeds of a total of six tree species, that can form dominant stands in the studied region. Three species were nonnative invasives in the region (Pinus ponderosa, Pinus contorta and Pseudotsuga mensiezii), and the other three were native species (Austrocedrus chilensis, Nothofagus obliqua and Araucaria araucana). We found that in the high harvesting intensity treatments, the establishment after 2 years of all nonnative trees and only one native species (A. araucana) was increased in spite of the ecological and structural differences (i.e., productivity levels) between sites. Invasion by nonnative tree species can have important negative economic and ecological consequences on the logged ecosystems, so their removal may be required to keep them away from colonizing and dominating the logged areas, especially at high harvesting intensities. [ABSTRACT FROM AUTHOR]

Most reforestation in Colombia, especially in the Andean region, are monocultures of pines and eucalyptus with defined nursery and silvicultural packages. Planting native species would avoid the widespread controversy over reforestation with exotic species. Nevertheless, there are few studies that evaluate the growth and yield of native species and provide supported data to establish new projects. Here, we modeled the growth and yield of the native coniferous Retrophyllum rospigliosii in different areas of the Colombian Andes in terms of mean diameter (D), height (H), and volume (V) as a function of age, based on longitudinal data from 115 research sample plots from three sites that were remeasured between 4 and 9 times for 20 years. We fitted the von Bertalanffy growth model for D, H, and V through Bayesian generalized nonlinear mixed models to model tree growth. The adjustment of the models for the absolute growth of R. rospigliosii was 0.99, 0.99, and 0.97 for D, H, and V, respectively. All models fulfilled all regression assumptions. Although the growth rates of R. rospigliosii differed between planted sites, R. rospigliosii plantations generally exhibited low growth and barely reached the sizes required for commercialization. These results suggest that the extensive use of R. rospigliosii in pure plantations is unlikely and discourages the massive propagation of R. rospigliosii. [ABSTRACT FROM AUTHOR]

The ability of non-native plant species to tolerate water scarcity and high temperatures, especially during the early stages of development, may influence their invasive potential. Ligustrum lucidum is a tree native to warm temperate areas of Asia. To understand the potential expansion of this non-native invasive species into more arid regions, we conducted an experiment in incubation chambers to evaluate seed germination under different water potentials and the response of its seedlings under different water availability and temperature scenarios. Seeds were collected from central Argentina and placed to germinate under four different water potentials (−0.2; −0.4; −0.7 and −1.2 MPa) created with polyethylene glycol 6000. Additionally, L. lucidum seedlings were subjected to contrasting levels of water availability combined with different periods of exposure to high temperatures. Germination measurements (germination percentage, velocity, and synchronicity) decreased at lower water potentials. No germination occurred at −0.7 and −1.2 MPa. The seedlings showed a slight increase in mortality and a significant reduction in most of the growth variables under low water availability, while exposure to high temperatures had significant effects only on chlorophyll estimate. The germination response of L. lucidum to water deficits could pose a significant constraint on its establishment in arid ecosystems. Nonetheless, this constraint may be alleviated by the species' prolific propagule production, coupled with asynchronous seed germination, which may help it exploit more humid micro-sites or sporadic water events. Furthermore, the drought tolerance of its seedlings strongly warns against the use of this species as an ornamental plant in arid environments. [ABSTRACT FROM AUTHOR]

A critical and common, but much ignored, plant-animal interaction is primary seed dispersal by ants (myrmecochory). Ants are ubiquitous across many landscapes, so it may not be surprising that many plants have evolved to utilize them to move their seeds. In fact, myrmecochory has independently evolved over 100 times. Myrmecochory carries all the usual benefits of biotic seed dispersal, such as reduction of competition with siblings, as well as a few more (notably, escape from fire). Seeds dispersed by ants generally possess an attached food body (elaiosome), which attracts and rewards ants. Elaiosomes are commonly described as fat bodies comprising lipids. However, their nutritional and chemical composition can vary widely, with some plant species producing elaiosomes with higher concentrations of protein or carbohydrates than of lipids. Elaiosomes of even quite closely related plant species can vary in chemical composition. Once ants encounter a seed with an elaiosome, they generally return to the nest with that seed, remove the elaiosome, and consume it, although which individuals within the nest consume the elaiosome is in many cases unclear. Once the elaiosomes have been removed, seeds are then disposed of either within the nest or outside of the nest, where they can be potentially secondarily dispersed by wind, water, or animals, including other ant species. This primer will focus on primary dispersal, the initial movement of seeds away from a parent plant. This primer defines myrmecochory, provides an overview of elaiosome traits, summarizes how ants choose and interact with elaiosome-bearing seeds, describes the current understanding of how elaiosomes evolved, and touches on how ant seed dispersal may respond to anthropogenic changes, such as the introduction of invasive species and climate change. This primer is guided by five major questions: (i) What is seed dispersal and myrmecochory? (ii) What are the benefits of myrmecochory? (iii) What is an elaiosome? (iv) How do ants choose and interact with seeds? (v) How did elaiosomes and myrmecochory evolve? [ABSTRACT FROM AUTHOR]

Premise of research. Little is known about the establishment success of grasses after their introduction into new areas. Using herbarium data, we investigated temporospatial patterns in the survival, establishment, and spread of grasses introduced to eastern North America through solid ballast deposition from the pre-twentieth-century shipping trade. Methodology. We identified 95 grass species introduced to New Jersey via ballast deposition and used 2729 digitized and georeferenced plant specimens from 63 herbaria to quantify their establishment and dispersion. Anselin Local Moran's I measure of local spatial autocorrelation revealed the earliest and most recent areas of invasion by ballast grasses irrespective of collection intensity. Species' native ranges were used to evaluate the differential establishment and dispersion of species from different biogeographic realms. Pivotal results. Of all the species (95), 51% did not survive after ballast deposition ended (waifs), 8% died out shortly thereafter (short-term), and 41% became established in New Jersey. Of the established species, 41% are widespread (established-widespread), and 59% are still primarily found near shipping ports and railroads (established–limited spread). These species are mostly native to the Palearctic (77%; 44% to the Mediterranean and 33% to northern Europe), followed by the Neotropics (11%), the Afrotropics (10%), and the southeastern United States (4%). The establishment proportion for species native to more than one biogeographic region (72%) was four times greater than that for species native to a single region (18%). Additionally, 95% of established species, including all established-widespread species, are native to the Eastern Hemisphere. Conclusions. We present the first analysis of the establishment proportion for a large set of grasses introduced through a single vector to a single area. We show the impact of biogeographic origin on the establishment proportion of introduced grasses and highlight the utility of herbarium collections for studying nonnative species' history. [ABSTRACT FROM AUTHOR]

We examined the feeding habits and seasonal changes in invasive masked palm civets (Paguma larvata) in northern Japan, to understand their feeding strategies. Between 2020 and 2022, we collected 98 fecal samples from masked palm civets and analyzed their content. The civets fed mainly on fruits (78 % in terms of the point-frame method) and arthropods (15 %); fruits were consumed throughout the year, but increased in winter when arthropods were not available. The feeding plasticity of masked palm civets, in addition to their physical and behavioral adaptations, enables them to expand their distribution in introduced habitats in temperate regions. [ABSTRACT FROM AUTHOR]

Copyright of Phegea is the property of Vlaamse Vereniging voor Entomologie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Invasive alien species (IAS) are one amongst the dominant drivers of global environmental change. The reported effects of IAS on biodiversity and ecosystems are often highly variable across species, habitats, and environmental settings, which constrains our capacity to empirically generalise their overall impact. To date, meta‐analyses have investigated the ecological impacts of IAS using only mean effects, while variance effects – an equally important measure in quantifying the efficacy or generalizability of a treatment – has largely remained ignored. Using a global meta‐analysis of 586 and 522 effect sizes related to mean and variance measures respectively from 30 studies, here we provide the first quantitative synthesis of the extent to which a global plant invader Lantana camara affects the mean and variance of ecological variables relevant at species, community and ecosystem levels. Our results suggest that for individual response classes, both the mean and variance effects from the species invasion differed considerably in their magnitude and direction, with the effect on most response classes being highly heterogeneous and non‐significant. The study design had a significant effect on both the mean and variance effects from the species invasion, but the ecosystem type, continent, and latitude act as weak predictors of both mean and variance effects. By investigating both mean and variance effects, our study provides first quantitative synthesis on ecological impacts of a globally problematic invasive plant. Based on our findings, we highlight the current knowledge gaps and suggest future research directions, particularly the need to focus on causes of variance in invasion impact studies for effective management and restoration of invaded landscapes. [ABSTRACT FROM AUTHOR]

The perception of eight invasive alien plant species (IAPS) by 311 children and young people (10–24 years old) and their choice of management options were investigated, either with or without prior information about the IAPS given. In the first questionnaire, photographs of the IAPS (four terrestrial herbs, one tree and three aquatic plants) were presented, but their invasive status was not revealed. Participants characterized each plant by five opposing attributes, e.g. unwanted – wanted. In a consecutive second questionnaire, half of the participants were informed about the invasive character of the plants, the other half not. Both groups then evaluated various management options. Plants with attractive flowers were considered most beautiful and wanted. Moreover, if participants perceived an IAPS as familiar, they considered it native. Participants with information about the IAPS were more likely to choose containment or eradication and were also more able to justify their management decisions in a considerate manner. Participants without information were more likely to choose no intervention, especially in case of flowering forbs. The findings indicate that even a brief information about IAPS might help young people to make informed decisions when dealing with invasive species. [ABSTRACT FROM AUTHOR]

Exotic plant invaders can promote others via direct or indirect facilitation, known as "invasional meltdown." Increased soil nutrients can also promote invaders by increasing their competitive impacts, but how this might affect meltdown is unknown. In a mesocosm experiment, we evaluated how eight exotic plant species and eight Eurasian native species responded individually to increasing densities of the invasive plant Conyza canadensis, while varying the supply and fluctuations of nutrients. We found that increasing density of C. canadensis intensified competitive suppression of natives but intensified facilitation of other exotics. Higher and fluctuating nutrients exacerbated the competitive effects on natives and facilitative effects on exotics. Overall, these results show a pronounced advantage of exotics over native target species with increased relative density of C. canadensis under high nutrient availability and fluctuation. We integrate these results with the observation that exotic species commonly drive increases in soil resources to suggest the Resource‐driven Invasional Meltdown and Inhibition of Natives hypothesis in which biotic acceleration of resource availability promotes other exotic species over native species, leading to invasional meltdown. [ABSTRACT FROM AUTHOR]

Urban forests provide ecosystem services important for regulating climate, conserving biodiversity, and maintaining human well‐being. However, these forests vary in composition and physiological traits due to their unique biophysical and social contexts. This variation complicates assessing the functions and services of different urban forests. To compare the characteristics of the urban forest, we sampled the species composition and two externally sourced traits (drought tolerance and water‐use capacity) of tree and shrub species in residential yards, unmanaged areas, and natural reference ecosystems within six cities across the contiguous US. As compared to natural and unmanaged forests, residential yards had markedly higher tree and shrub species richness, were composed primarily of introduced species, and had more species with low drought tolerance. The divergence between natural and human‐managed areas was most dramatic in arid climates. Our findings suggest that the answer to the question of "what is an urban forest" strongly depends on where you look within and between cities. [ABSTRACT FROM AUTHOR]

Summary: Ectomycorrhizal (ECM) fungi distribute tree‐derived carbon (C) via belowground hyphal networks in forest ecosystems. Here, we asked the following: (1) Is C transferred belowground to a neighboring tree retained in fungal structures or transported within the recipient tree? (2) Is the overlap of ectomycorrhizal fungi in mycorrhizal networks related to the amount of belowground C transfer?We used potted sapling pairs of European beech (Fagus sylvatica) and North‐American Douglas‐fir (Pseudotsuga menziesii) for 13CO2 pulse‐labeling. We compared 13C transfer from beech (donor) to either beech or Douglas‐fir (recipient) and identified the ECM species. We measured the 13C enrichment in soil, plant tissues, and ECM fractions of fungal‐containing parts and plant transport tissues.In recipients, only fungal‐containing tissue of ectomycorrhizas was significantly enriched in 13C and not the plant tissue. Douglas‐fir recipients shared on average one ECM species with donors and had a lower 13C enrichment than beech recipients, which shared on average three species with donors.Our results support that recently assimilated C transferred belowground is shared among fungi colonizing tree roots but not among trees. In mixed forests with beech and Douglas‐fir, the links for C movement might be hampered due to low mycorrhizal overlap with consequences for soil C cycling. [ABSTRACT FROM AUTHOR]

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Non-native species can react to changes to their thermal environment by altering their feeding behaviour, thereby potentially causing shifts in predator–prey dynamics and competitive dominance over native species. In this study, we measured intraspecific variation in the functional response (i.e., predation rate as a function of prey density) of the rusty crayfish Faxonius rusticus (Girard, 1852) at two temperatures (18 °C and 26 °C) in the laboratory. We compared six invasive populations spanning a 2° latitudinal gradient in eastern North America to test the prediction that under warmer conditions individuals from more southerly populations exhibit a higher functional response than those from northern populations. Temperature, latitude, and the interaction between these two variables had significant effects on attack rates and handling times of individual crayfish from the tested populations. Contrary to our prediction, the attack rates of individuals from northern populations were consistently higher than those from southern populations at both temperatures. We propose that these interpopulation differences in functional response could arise, at least in part, from countergradient selection. Our results suggest that climate warming promotes spatiotemporal variation in per capita effects across latitudinally distributed populations of aquatic invasive species. [ABSTRACT FROM AUTHOR]

The introduction of non-indigenous species (NIS) to exotic habitats can have tremendous impacts on native biodiversity, food webs, and ecosystem services. One globally distributed aquatic NIS is the hydrozoan Craspedacusta sowerbii Lankester, 1880. The species' northern distribution boundary in North America is situated in British Columbia (BC), Canada. It is thus of paramount interest to understand its ecology in this warming invaded habitat, allowing for insights into other regions. Specimens of the genus Craspedacusta have been reported in 34 freshwater systems since August 1990. These reported locations are generally shallow (<10 m), most often of natural origin, and have a small surface area (<0.1 km2). We observed an exponential trend of medusa observations from 1990 till the end of the 2020s. The first seasonal records are in July and the latest in October, with peak sightings reported in August and September. After 2012, regional temperature anomalies during July and August were mostly positive, which overlaps with the period of the majority of reported C. sowerbii sightings. Until this day, all examined medusae are males. [ABSTRACT FROM AUTHOR]

In the 19th century, a lower intertidal macrophyte, Fucus serratus (Linnaeus), from western Europe was introduced to Nova Scotia, Canada, where it successfully established, co-existing with native macrophytes Fucus vesiculosus (Linnaeus) and Ascophyllum nodosum (Linnaeus). We first examined whether a common gastropod in Nova Scotia, Littorina obtusata (Linnaeus, 1758), which grazes on the native macrophytes, has exploited the invasive and on finding this, we secondly examined whether there has been any phenotypic differentiation on the invasive. Among 98 sites surveyed around Nova Scotia and Newfoundland in May and June 1994, 11 had the invasive macrophyte, all of which showed colonization by L. obtusata including egg masses, juveniles, and adults. Among 2135 shells photographed for digital image analyses, those on the invasive differed from those on the native macrophytes with respect to (1) RGB (red/green/blue) channels, (2) HSV (hue, saturation, brightness) phenotypes, (3) protoconch pattern, and (4) adult shell size. Nitrogen and carbon stable isotope signatures on muscle tissues from a subset of L. obtusata indicate foraging fidelity on the invasive rather than temporary occupation. We suggest that these cumulative phenotypic responses to the invasive macrophyte that vary in extent and direction within and among localities reflect localized adaptation and offer a unique opportunity for quantifying early stages of phenotypic and genomic differentiation in a novel ecological niche. [ABSTRACT FROM AUTHOR]

The increasing intrusion of weed species into alpine regions is an alarming threat to native floras because their strong and deep root systems cause a scarcity of nutrients to native alpine plant species. Considering the sensitive nature of alpine ecosystems, integrated weed management may be a means of preventing invasive species from going out of control. The present study investigated the allelopathic effect of Elsholtzia strobilifera on the germination and growth characteristics of Himalayan knotweed (Koenigia polystachya, syn. Polygonum polystachyum) under both field and laboratory conditions. The germination of seeds under laboratory conditions was studied by using different dilutions of hydrosol and aqueous extracts derived from E. strobilifera. In our field study, seedlings of K. polystachya were planted together with E. strobilifera in their natural habitat at a nursery. The study indicates that the seed germination and morphological parameters of seedlings were significantly inhibited by different dilutions of hydrosol and extract (reduction by 83–96% and 62–73%, respectively). In field conditions, significant inhibition in the morphological characteristics of K. polystachya was observed when grown in association with E. strobilifera. The results reveal that E. strobilifera has a significant allelopathic effect on K. polystachya. Based on the results of the present study, it can be concluded that growing plants of E. strobilifera around K. polystachya may be a novel approach to curbing the spread of the latter and suppressing the population of this species in ecologically sensitive alpine or other endangered areas. [ABSTRACT FROM AUTHOR]

Horizon scans have emerged as a valuable tool to anticipate the incoming invasive alien species (IAS) by judging species on their potential impacts. However, little research has been conducted on quantifying actual impacts and assessing causes of species‐specific vulnerabilities to particular IAS due to persistent methodological challenges. The underlying interspecific mechanisms driving species‐specific vulnerabilities therefore remain poorly understood, even though they can substantially improve the accuracy of risk assessments. Given that interspecific interactions underlying ecological impacts of IAS are often shaped by phenological synchrony, we tested the hypothesis that temporal mismatches in breeding phenology between native species and IAS can mitigate their ecological impacts. Focusing on the invasive American bullfrog (Lithobates catesbeianus), we combined an environmental DNA (eDNA) quantitative barcoding and metabarcoding survey in Belgium with a global meta‐analysis, and integrated citizen‐science data on breeding phenology. We examined whether the presence of native amphibian species was negatively related to the presence or abundance of invasive bullfrogs and whether this relationship was affected by their phenological mismatches. The field study revealed a significant negative effect of increasing bullfrog eDNA concentrations on native amphibian species richness and community structure. These observations were shaped by species‐specific vulnerabilities to invasive bullfrogs, with late spring‐ and summer‐breeding species being strongly affected, while winter‐breeding species remained unaffected. This trend was confirmed by the global meta‐analysis. A significant negative relationship was observed between phenological mismatch and the impact of bullfrogs. Specifically, native amphibian species with breeding phenology differing by 6 weeks or less from invasive bullfrogs were more likely to be absent in the presence of bullfrogs than species whose phenology differed by more than 6 weeks with that of bullfrogs. Taken together, we present a novel method based on the combination of aqueous eDNA quantitative barcoding and metabarcoding to quantify the ecological impacts of biological invaders at the community level. We show that phenological mismatches between native and invasive species can be a strong predictor of invasion impact regardless of ecological or methodological context. Therefore, we advocate for the integration of temporal alignment between native and IAS's phenologies into invasion impact frameworks. [ABSTRACT FROM AUTHOR]

Government agencies and landowners use a variety of lethal methods to reduce invasive wild pig populations and resulting agricultural damages. To provide decision-makers with information regarding Alabama farmers' experiences with wild pigs and their preferences for management actions, we surveyed Alabama Farmers Federation members in 2020. We found that wild pigs were commonly present on livestock, timber, and crop production acreage, but wild pig damages and costs were much more common among crop producers. Respondents' wildlife acceptance capacity for wild pigs was low and all lethal control methods were considered acceptable by most respondents, particularly those performed by landowners. While there is likely a consensus among Alabama farmers that wild pig numbers need to be reduced within the state, managers should continue to build support by working closely with crop producers and by addressing potential concerns regarding the implementation of methods by government agencies in future initiatives and outreach. [ABSTRACT FROM AUTHOR]

The article discusses the issue of prioritizing novelty in scientific research and its potential negative impact on significant conservation domains. The author argues that rejecting papers based on novelty alone can impede scientific and social progress, as these studies often have crucial policy and practical implications. The article emphasizes the importance of research rigor and a balanced approach that includes both conceptual innovation and practical research. It highlights the need for further studies in conservation domains to address global challenges and ensure the preservation of ecosystems and human well-being. The author suggests that the evaluation process for publication should prioritize research diversity, practical implications, and long-term sustainability. The article concludes by advocating for a reconsideration of the emphasis on novelty in conservation sciences, as rejecting articles on important topics can compromise scientific knowledge and hinder efforts to address real-world challenges. [Extracted from the article]

Sea-level rise (SLR) will produce unprecedented changes in tidal marsh systems that already cope with daily tidal fluctuation, disturbances from storms, and salinity changes from droughts and runoff events. Additionally, negative impacts from non-native invasive species may alter marsh plants' ability to respond to SLR stressors like increased inundation and salinity. Increasingly, tidal marsh communities must tolerate both changes in the physical environment from SLR and increased risk of invasion by non-native species. To assess the response of a threatened tidal marsh cordgrass (Spartina foliosa) to both stressors, we implemented a field experiment in San Francisco Bay, CA, USA, exposing cordgrass to a treatment that extended tidal inundation projected with SLR using a recently developed in situ method. At one of two field sites, we also enclosed the cordgrass with or without the invasive European green crab, Carcinus maenas. We found that cordgrass responded negatively to longer inundation, although these effects varied by site and year. In higher inundation treatments, cordgrass survival increased with increasing surface elevation of the plot. Cordgrass survival was lower in the presence of invasive green crabs relative to controls. We did not find interacting effects of responses to increased inundation and invasive species presence, which highlights the need to consider how latent or sequential effects of multiple stressors may affect ecosystems. This study demonstrates significant biological responses to invasive species presence and increased inundation. Evaluating relative effects and timing of multiple stressors, especially those induced by climate change and invasive species, will help us to manage threatened ecological communities in a changing world. [ABSTRACT FROM AUTHOR]

Oceanic islands are a major tourist destination, and the invasion of exotic plants on oceanic islands is a serious problem. To discuss how exotic herbaceous plant invasion is driven by human disturbance on an oceanic island, we assessed the distribution patterns of exotic herbaceous species along a metropolitan road, including parking lots, on the island of Chichijima in the Ogasawara Islands of Japan in the North Pacific Ocean. We observed 16 exotic herbaceous species representing seven families, and all the species have also been recorded in surveys 25 years ago. Species richness (number of species per plot) ranged from 0 to 9 with an average of 2.49. Distance from a parking lot was significantly negatively related to the distribution patterns of seven species and positively related to three species, pointing to parking lots being critical nodes along the dispersal pathways of exotic herbaceous species in Chichijima. Although roads are well known to play an important role as corridors for the invasion and seed dispersal of exotic plants, our results suggest that it would also be important to consider the location of parking lots to understand the distribution of exotic herbaceous species in road networks. We suggest that intensive weed management near parking lots and car wash protocols on Chichijima may be effective in halting exotic species spread. [ABSTRACT FROM AUTHOR]

Cat's claw creeper (Dolichandra unguis‐cati), native to tropical South America, is a major invasive species and a target for biological control in Australia, South Africa and some South Pacific Island countries. Native range surveys in Argentina, Brazil, Paraguay and Venezuela have identified eight insects and four fungal pathogens as potential agents. Five leaf‐feeding insects a tortoise beetle Charidotis auroguttata, two tingids Carvalhotingis visenda and C. hollandi, a leaf‐tying moth Hypocosmia pyrochroma and a leaf‐mining beetle Hedwigiella jureceki, have been tested and all were released in South Africa. Four of these have become established but are not widespread and cause only limited damage. In Australia, only three of these, C. visenda, H. pyrochroma and H. jureceki were released, while C. auroguttata was not approved due to perceived non‐target risks. All agents have become widely established, except for H. pyrochroma which is restricted to riparian corridors in southeast Queensland. In South Africa, an accidentally introduced leaf‐spot pathogen, Neoramulariopsis unguis‐cati, causes necrotic lesions and premature abscission of leaves in cat's claw creeper infestations, resulting in widespread defoliation. Based on its impact and field‐host specificity in its native range and in South Africa, the pathogen has been prioritised for evaluation as a potential additional agent in Australia. The current priority is to seek approval for the introduction of this leaf‐spot pathogen into Australia. Future research should focus on the gall‐inducing rust Uropyxis rickiana and the seed‐feeding weevil Apteromechus notatus as prospective agents. [ABSTRACT FROM AUTHOR]

Geographically expanding and invading ticks are a global concern. The Asian longhorned tick (ALT, Haemaphysalis longicornis) was introduced to the mid‐Atlantic US between 2010 and 2017 and recently invaded Ohio, an inland state. To date, ALTs in the US have been associated with livestock exsanguination and transmission of the agent of bovine theileriosis. To inform management, studies describing tick ecology and epidemiology of associated disease agents are critical. In this study, we described phenology, habitat and host associations, and tested for agents of medical and veterinary concern at the site of the first known established ALT population in Ohio, where pesticide treatment was applied in early fall 2021. In spring–fall 2022, we sampled wildlife (small mammals) and collected ticks from forest, edge, and grassland habitats. We also opportunistically sampled harvested white‐tailed deer at nearby processing stations and fresh wildlife carcasses found near roads. Field‐collected ALTs were tested for five agents using real‐time PCR. We found that ALT nymphs emerged in June, followed by adults, and concluded with larvae in the fall. ALTs were detected in all habitats but not in wildlife. We also found a 4.88% (2/41) prevalence of Anaplasma phagocytophilum across ALT adults and nymphs. Host and habitat associations were similar to other studies in the eastern United States, but two potential differences in phenology were identified. Whether ALTs will acquire more endemic disease agents requires further investigations. Our findings provide the first evidence regarding ALT life history from the Midwest region of the United States and can inform exposure risk and guide integrated management. [ABSTRACT FROM AUTHOR]

The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), is an invasive pest species that has incurred massive economic damages in areas cultivating economically important crops like corn, rice, cotton and many others. Known to be a native of the Western Hemisphere, FAW has since then established itself in many parts of Africa, Asia and Australia and Oceania. The Philippines had been among the Asian countries vulnerable to FAW invasion, which was validated in June 2019. This study aims to characterize the existing strains and haplotypes of FAW and describe the genetic structure and the signature of its recent demographic history nationwide. COI sequences reveal the predominance of rice‐strain over the corn‐strain FAW, while Tpi sequences are more accurate in defining the corn‐strain found in corn and sugarcane. Discordant COI‐Tpi configurations frequently occur the most in the entire FAW population at 65.29%. Nucleotide and haplotype diversity are low with an average of 0.005976 and 0.4019 respectively. In addition to non‐significant values in neutrality tests suggesting neutral evolution, the low nucleotide and haplotype diversity indicate population contraction from founder effect. Variations are mostly found within regions, and genetic structure is moderate among regions (FST = 0.14375). These results can be attributed to low selective pressures accompanying its establishment, or more likely due to recent migration and/or human‐assisted factors such as trade. Implications on pest management and prospective studies in the future are also discussed in this study. [ABSTRACT FROM AUTHOR]

Vayssierea is an understudied nudibranch genus characterized by its orange colouration and small size (up to 5 mm in length). To date, there are four described species, distributed in the Indo-Pacific Ocean. Here, individuals of Vayssierea were recorded for the first time in the North Atlantic Ocean on the Canary Islands (Spain). This study aims to evaluate the systematic and taxonomic status and distribution of the genus through multilocus phylogenetic, morphological, and radular analyses. Phylogenetic results show the monophyly of Vayssierea and evidence indicating that the genus is included in the new subfamily Okadaiinae stat. nov. within Polyceridae. According to species delimitation tests, four different species have been sequenced from Russia to Australia, in addition to our new records in the Atlantic Ocean, but more information is needed to identify the species. Nevertheless, our specimens from the Canary Islands belong to two different species, one of which is identical to the Australian species. Bearing in mind that they lack a planktonic larval stage; we hypothesize that they arrived by shipping transportation or aquarium releases, becoming a non-indigenous species of the Atlantic Ocean. [ABSTRACT FROM AUTHOR]

Aquatic invasive species can affect food web structure, native fish growth, and production, depending on the traits of the invasive species and the pre-invasion conditions of the ecosystem. Thermal tolerances and behavioral traits can further influence differential exploitation of resources shared between native and invasive species. An unauthorized introduction of redside shiner (Richardsonius balteatus) into reservoirs in the Upper Skagit River, Washington, USA caused concern of potential competition, decreased production, and recruitment of rainbow trout (Oncorhynchus mykiss). We combined bioenergetics modeling and stable isotope analysis with field data to quantify consumption demand of native and invasive fishes and related consumption to the availability of key zooplankton prey. Per capita consumption on Daphnia by redside shiner was low; however, their high abundance imposed considerable demand on prey resources in Ross Lake. Although monthly consumption demand by the fish community was less than 50% of the monthly production and biomass of Daphnia in Ross Lake, the current Daphnia densities and growth of rainbow trout were considerably lower than before the invasion. These reductions correspond to lower annual consumption of Daphnia. Our study provides insight on mechanisms that influence food web impacts of an invasive omnivore in cold-water reservoirs. [ABSTRACT FROM AUTHOR]

Invasive species pose serious threats to global biodiversity, prompting studies to identify factors underlying invasion and establishment success. However, it's difficult to discern these factors due to the absence of survey data since the initial invasion, because introduced species often remain unnoticed until their population becomes large enough. Here, we investigated the establishment process of the alien zooplankton, Daphnia pulicaria, in the past 30 years using sedimentary archives at Lake Biwa. We performed genetic analysis on mitochondrial DNA sequences of the control region and ND5 gene of ephippia in sediments, as well as present females from water samples. Furthermore, we investigated the relationships between the abundance of D. pulicaria and its major predator fish, Ayu, based on the catch data, as well as its competitor, Daphnia galeata whose abundance was inferred from claw remains. Our analyses showed the studied mitochondrial sequences were identical between all samples. The abundance of D. pulicaria was not correlated with that of a competitor but was negatively with that of a predator. These findings suggest the successful establishment of D. pulicaria was primarily influenced by reduced predation pressure, with a limited impact from competitive interactions and potential hindrance for adaptation caused by loss of genetic variation. [ABSTRACT FROM AUTHOR]

Invasive species often undergo demographic bottlenecks that cause a decrease in genetic diversity and associated reductions in population fitness. Despite this, they manage to thrive in novel environments. Investigating the effects of inbreeding and genetic bottlenecks on population fitness for invasive species is, therefore, key to understanding how they may survive in new environments. We used the blowfly Calliphora vicina (Sciences, Mathématiques et Physique, 1830, 2, 1), which is native to Europe and was introduced to Australia and New Zealand, to examine the effects of genetic diversity on population fitness. We first collected 59 samples from 15 populations across New Zealand and one in Australia, and used 20,501 biallelic SNPs to investigate population genomic diversity, structure and admixture. We then explored the impacts of repeated experimental bottlenecks on population fitness by creating inbred and outbred lines of C. vicina and measuring a variety of fitness traits. In wild‐caught samples, we found low overall genetic diversity, signals of genetic admixture and limited (<3%) genetic differentiation between North and South Island populations, with genetic links between the South Island and Australia. Following experimental bottlenecks, we found significant reductions in fitness for inbred lines. However, fitness effects were not felt equally across all phenotypic traits. Moreover, they were not enough to cause population collapse in any experimental line, suggesting that C. vicina (when under relaxed selection, as in laboratory settings) may be able to compensate for population bottlenecks even when highly inbred. Our results demonstrate the value of a tractable experimental system for investigating processes that may facilitate or hamper biological invasion. [ABSTRACT FROM AUTHOR]

Globalization has led to the frequent movement of species out of their native habitat. Some of these species become highly invasive and capable of profoundly altering invaded ecosystems. Feral swine (Sus scrofa × domesticus) are recognized as being among the most destructive invasive species, with populations established on all continents except Antarctica. Within the United States (US), feral swine are responsible for extensive crop damage, the destruction of native ecosystems, and the spread of disease. Purposeful human‐mediated movement of feral swine has contributed to their rapid range expansion over the past 30 years. Patterns of deliberate introduction of feral swine have not been well described as populations may be established or augmented through small, undocumented releases. By leveraging an extensive genomic database of 18,789 samples genotyped at 35,141 single nucleotide polymorphisms (SNPs), we used deep neural networks to identify translocated feral swine across the contiguous US. We classified 20% (3364/16,774) of sampled animals as having been translocated and described general patterns of translocation using measures of centrality in a network analysis. These findings unveil extensive movement of feral swine well beyond their dispersal capabilities, including individuals with predicted origins >1000 km away from their sampling locations. Our study provides insight into the patterns of human‐mediated movement of feral swine across the US and from Canada to the northern areas of the US. Further, our study validates the use of neural networks for studying the spread of invasive species. [ABSTRACT FROM AUTHOR]

Using a DNA barcoding approach, we document an extensive number of interspecies cryptic introductions of bladed Bangiales (Pyropia) at an historic oyster aquaculture site in the Southern North Sea. We sampled the intertidal of 20 locations along the Belgian and Dutch coastline, ranging from sheltered to exposed, between February 2022 and April 2023 for bladed Bangiales. 230 individuals of bladed Bangiales were collected, morphological and ecological characteristics described and identified based on chloroplast rbcL gene sequences, revealing the presence of 13 species belonging to the genera Porphyra and Pyropia. While seven species (P. dioica, P. linearis, P. purpurea, P. umbilicalis, Py. collinsii, Py. elongata, Py. leucosticta) are regarded as native to the Northeast Atlantic, four species (Py. katadae, Py. koreana, Py. kinositae and Py. yezoensis) are considered non-indigenous. The records of Py. katadae, Py. kinositae and Py. koreana are the first confirmed observations for the Northeast Atlantic region. In addition, we identified two distinct rbcL clades, for which a definite species identification could not be established due to a lack of matching reference sequences. Species diversity was generally higher during winter and at exposed sites facing the open North Sea. The surprisingly high species diversity of the bladed Bangiales could only be revealed by molecular identification -- a crucial tool for reliable species identification in this group of organisms. [ABSTRACT FROM AUTHOR]

Birds use sound for conspecific communication. According to the acoustic niche hypothesis, they avoid signal competition with other species by partitioning sound in frequency and time. Others have observed introduced species changing the vocal behavior of native species; however, communitylevel effects of multiple introduced species remain unknown. Hawai'i, with its legacy of bird extinctions followed by a surge of human introductions, offers a unique opportunity to study acoustic signal partitioning between native and introduced species. We predicted that communities with higher percentages of introduced birds would exhibit more acoustic overlap between members of different species due to shorter time frames to evolve signal partitioning. Using autonomous recording units, we recorded forest bird communities during the summer in montane primary and secondary forests as well as a low-elevation agricultural site. Random samples of recordings from each site were visualized as spectrograms, and all bird vocalizations >5 decibels above background noise were identified and labeled by species. Frequency range and the proportion of overlap with other species were compared between native and introduced species. We also used a null model which randomized the start time of each bird vocalization within a location over 500 iterations, then compared the amount of heterospecific signal overlap in the randomizations to that observed in the recordings. While native and introduced species generally used similar frequency ranges, native-native heterospecific species vocalization pairs had a significantly higher proportion of overlap than introduced-native and nativenative pairs. Additionally, the incidence of signal overlap in the original recordings tended to be lower than in the null model randomizations, but this difference was not significant, and was not influenced by the percentage of introduced species vocalizations at the site. The lack of significant difference between observed and null model signal overlap occurrence suggests that native and introduced forest birds were not partitioning acoustic space either spectrally or temporally, and that introduced birds are not strongly influencing signal partitioning in forest bird communities of Hawai'i. However, this may have been a consequence of recording during the non-breeding season, and future work should compare vocal activity in native and introduced birds throughout the year. [ABSTRACT FROM AUTHOR]

Introduction: Soil drought during summer in Central Europe has become more frequent and severe over the last decades. European forests are suffering increasing damage, particularly Norway spruce. Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco), a non-native tree species, is considered as a promising alternative to build drought-resilient forests. The main goal of this study was to investigate the intraannual radial stem growth and sap flow performance of Douglas-fir along a precipitation gradient across Germany under severe drought. Material and methods: Sap flow and stem radial changes of up to ten trees each at four sites with different precipitation regimes were measured in combination with volumetric soil water content during the growing season of 2022. Measurements of stem radial changes were used to calculate the trees' stem water deficit, a proxy for tree water status and drought stress. Results: The severe summer drought of 2022 led to an early growth cessation and a significant reduction in daily sap flow at all four sites monitored. We could identify a site-specific threshold in soil water availability ranging between 21.7 and 29.6% of relative extractable water (REW) under which stem water reserves cannot be replenished and thereby inhibiting radial growth. We could also demonstrate that at this threshold, sap flow is heavily reduced to between 43.5 and 53.3%, and for a REW below 50%, sap flow linearly decreases by 1.1-2.0% per 1% reduction in REW. This reduction tends to follow the humidity gradient, being more pronounced at the most oceanic characterized site and suggesting an adaptation to site conditions. Even though Douglas-fir is considered to be more drought stress resistant than Norway spruce, growth and sap flow are greatly reduced by severe summer drought, which became more frequent in recent years and their frequency and intensity is likely to increase. Conclusions: Our results suggest that timber production of Douglas-fir in Central Europe will decline considerably under projected climate change, and thus pointing to site specific growth constraints for a so far promising non-native tree species in Europe. [ABSTRACT FROM AUTHOR]

Various attributes are hypothesized to facilitate the dominance of an invasive species in non-native geographical and ecological regimes. To explore the characteristic invasive attributes of the family Asteraceae, a comparative study was conducted among nine species of this family, co-occurring in the western Himalayan region. Based on their nativity and invasion status, the species were categorized as "Invasive", "Naturalized", and "Native". Fifteen plant functional traits, strongly linked with invasion, were examined in the test species. The analyses revealed a strong dissimilarity between all the plant functional traits (except leaf carbon [Leaf C]) represented by "Invasive" and "Native" categories and most of the traits (except leaf area [LA], leaf nitrogen [Leaf N], Leaf C, and leaf carbon-nitrogen ratio [C: N]) represented by the "Naturalized" and "Native" categories. Similarly, "Invasive" and "Naturalized" categories also varied significantly for most of the traits (except Leaf N, Leaf C, capitula per m² population [Cm²], seeds per capitula [Scapitula], and seed mass). Invasive species are characterized by high LA, specific leaf area [SLA] and germination, and low C:N and leaf construction costs [LCC]. Most of the traits represented by native species justify their non-invasive behavior; whereas the naturalized species, despite having better size metrics (plant height), resource investment strategy (aboveground non-reproductive biomass [BNR], and aboveground reproductive biomass [BR]), and reproductive output (capitula per individual plant [Cplant], and seeds per individual plant [Splant]) failed to invade, which implies that the role of these functional aspects in imparting invasion potential to a species is not consistent in all the ecosystems and/or phylogenetic groups. Results of PCA revealed that trait divergence plays a more imperative role in invasion success than naturalization in the species of the family Asteraceae. The present study is intended to refine the pre-generalized invasion concepts associated with family Asteraceae to ensure more accurate identification of the potential invaders and better management of the existing ones. [ABSTRACT FROM AUTHOR]

The honey bee (Apis mellifera) parasitic mite, Varroa destructor, is considered one of the main causes of colony losses in European honey bee (EHB) populations around the world. However, some EHB and Africanized honey bee (AHB) populations (derived from the African subspecies A. m. scutellata) that inhabit tropical and subtropical regions of the Americas, have survived varroa mite infestations in the absence of acaricide treatments. It is conceivable to expect that these honey bee populations, which have been subjected to natural selection over decades, would have developed resistance against V. destructor or possess pre-existing adaptations that allow them to survive mite parasitism. Here, we present a comprehensive literature review describing the spread of V. destructor and the honey bee populations occurring in Latin America (LA), and summarize the evidence of resistance of those populations to V. destructor. We also analyze reports describing the potential mechanisms of mite resistance and how they operate in those honey bee populations. Studies of a few EHB, as well as of numerous AHB populations exhibiting resistance to V. destructor in LA, unveil the existence of evolutionary adaptations that restrain V. destructor population growth and provide insight into the current host-parasite relationship. This review supports the notion that selective breeding of local honey bee populations from LA could be a viable strategy to manage varroa mite infestations in colonies. [ABSTRACT FROM AUTHOR]