Unintentional Introduction Research Articles

Pathways for accidental biocontrol: The human-mediated dispersal of insect predators and parasitoids.

Introductions of insect predators and parasitoids for biological control are a key method for pest management. Yet in recent decades, biological control has become more strictly regulated and less frequent. Conversely, the rate of unintentional insect introductions through human activities is rising. While accidental introductions of insect natural enemies can potentially have serious ecological consequences, they are challenging to quantify as their movements go largely unobserved. We used historical border interception records collected by the US Department of Agriculture from 1913 to 2018 to describe the diversity of entomophagous insects transported unintentionally, their main introduction pathways, and trends in host specificity. There were 35,312 interceptions of insect predators and parasitoids during this period, representing 93 families from 11 orders, and 196 species from these families. Commodity associations varied, but imported plants and plant products were the main introduction pathway. Most interceptions originated with commodities imported from the Neotropical, Panamaian, and Western Palearctic regions. Among the intercepted species, 27% were found in material originating from more than one country. Two thirds of species were polyphagous host generalists. Furthermore, 25% of species had already been introduced intentionally as biological control agents internationally, and 4.6% have documented negative impacts on native biodiversity or human society. Most of the intercepted species that have not established in the United States are host generalists or have at least one known host species available. The unintentional transport of diverse natural enemy insects has the potential to cause substantial ecological impacts, both in terms of controlling pests through accidental biocontrol and disrupting native communities. Characterizing the insects being transported and their introduction pathways can inform biosecurity practices and management.

Different mulch films, consistent results: soil fauna responses to microplastic

Agricultural activities contribute to plastic pollution, with unintentional introduction and intentional use of plastic mulch films leading to the accumulation of microplastic particles in soils. The lack of removal techniques and scarce information on the effects on soil organisms, especially for biodegradable mulch films, necessitate an assessment of potential effects. This study aimed to elucidate the effects of mulch film microplastic on soil fauna by investigating reproduction output and subcellular responses before and after recovery from exposure. Two common soil organisms, Folsomia candida and Eisenia fetida, were exposed to petroleum-based polyethylene (PE) and biodegradable polylactic acid/polybutylene adipate terephthalate (PLA/PBAT) microplastic for 28 days, according to OECD guidelines 232 and 222, respectively. Juvenile numbers revealed no polymer- or concentration-dependent effects on E. fetida and F. candida reproduction after exposure to up to 5 and 10 g/kgdw soil, respectively. To provide a more sensitive and early indication of sublethal effects, subcellular responses in E. fetida were analyzed. Glutathione S-transferase (GST) activity increased with rising microplastic concentration; however, catalase (CAT), acetylcholine esterase (AChE) activity, and reactive oxygen species (ROS) did not differ from control levels. Further, the more environmentally relevant PE polymer was chosen for in-depth assessment of subcellular response after 28-day microplastic exposure and subsequent 28 days in uncontaminated soil with E. fetida. No significant differences in biomarker activity and stress levels were observed. We conclude that mulch film–derived microplastic did not adversely affect earthworm and collembolan species in this scenario, except for a slight induction in the detoxification enzyme glutathione S-transferase.

Adaptation of two woody plant species – Betula pubescens and Salix udensis to the high Arctic conditions (Tiksi settlement, Russia)

The positive trends in climate change that have become apparent in recent decades are accompanied by a shift in the range boundaries of many boreal plant species further north, to the shores of the Arctic Ocean. Monitoring the displacement of these boundaries, the introduction of plants unusual to the Arctic, as well as monitoring their adaptation to new conditions, is an important component of botanical research. In 2016, in the village Tiksi identified 2 species of woody plants – Betula pubescens and Salix udensis, known from the forest zone and not previously observed in this area. Obviously, both species appeared here due to the unintentional introduction of seeds by humans. Repeated observations of the condition of these species, conducted in 2023, showed that they exhibit stable vitality, withstood 7 winter periods and gave some increase in phytomass. Measurements of the area of the leaf blade of Betula pubescens and the size of 10 leaves of Salix udensis showed that these indicators are within the normal biological parameters of these species. Both species do not form generative structures yet. Salix udensis has grown significantly during the observation period, reaching a height of about 2.5 m. Perhaps this is the result of the protective influence of the building behind which it develops. Betula pubescens grows more slowly, hardly retains orthotropic shoots exceeding the average snow cover levels, which reach a height of 54 cm, but at the same time partially drained and deprived of foliage. Nevertheless, the lower part of the plant has fully leafy branches. Both species are valuable objects for further observations of their adaptation to Arctic conditions. Since Betula pubescens grows near the slope of the highway, it is recommended to move it to a safe place less susceptible to anthropogenic influence. Tiksi village, located in high latitudes, could serve as a good reference base for a wide range of scientific observations of plant adaptation to Arctic conditions. The optimal solution for this would be the creation of the Arctic Botanical Garden in Tiksi.

Alien amphibian introductions via the plant trade: a breeding population of the Catalonian midwife toad (Alytes almogavarii) in Central Spain

Abstract The plant-trade is among the main sources of accidental introduction of alien biodiversity. This includes amphibians, although effective colonization pathways have rarely been reported except from tropical areas. We document the discovery of an established breeding population of the Catalonian midwife toad, Alytes almogavarii almogavarii Arntzen and García-París, 1995, in a plant nursery in Madrid (Central Spain), 400 km away from its natural distribution. During surveys in 2023 we found adults, juveniles, and tadpoles, confirming reproduction. We used mtDNA sequences to genotype six individuals for taxonomic assignment and tracing their putative origin. Two haplotypes were found, one of them showing a broad distribution, precluding precise identification of the source of the introduction. We discuss conservation concerns, including the potential spread of pathogens. Our results suggest unintentional amphibian introductions via the plant-trade may be more frequent than perceived, and call for rigorous monitoring and education efforts.

A new species of the genus Hyalesthes Signoret, 1865 (Hemiptera: Fulgoroidea: Cixiidae) from the Russian Black sea coast – Western Mediterranean faunal element in the Caucasus

AbstractA new species, Hyalesthes (Homalesthes) sagittus sp. n., of the family Cixiidae (Cixiinae, Pentastirini) is described from the Krasnodar Territory. The new species belongs to the Hyalesthes productus species group known from the Western Mediterranean and the Middle East. Natural disjunctive Western Mediterranean – Caucasian distribution as well as unintentional introduction of Auchenorrhyncha taxa are discussed.

Exploring the knowledge and application of biosecurity practices related to invasive alien species in field research in Croatia

Accidental introductions of invasive alien species (IAS) are increasingly prevalent and costly. Anthropogenic activities, including fieldwork activities of researchers, pose a risk for the unintentional spread of IAS. However, specific biosecurity policies and measures to prevent accidental introductions and the secondary spread of IAS are lacking in many European countries, primarily relying on researchers’ awareness of the issue. This study aimed to evaluate the biosecurity practices of researchers in Croatia during their fieldwork activities through an anonymous online survey distributed to over 63 institutions. The survey was completed by 172 respondents from 45 institutions and aimed to assess their knowledge of IAS and awareness of biosecurity risks they can pose. The results showed that even though more than half of the participants worked in the field of biology and had at least some knowledge of IAS, the majority used only the most basic and least efficient cleaning approaches for fieldwork equipment, clothes, and footwear, which are not sufficient for preventing unintentional IAS introductions. Moreover, vehicle cleaning was the most neglected biosecurity measure in our study, with up to 60 % of respondents never performing it and only 12 % always performing at least some type of vehicle cleaning. Respondents with the best knowledge of IAS posed a significant risk during their fieldwork activities but at the same time demonstrated the best understanding of biosecurity measures and had the best biosecurity performance. Furthermore, students were identified as a high-risk group since they visited the highest number of locations during fieldwork and used the equipment most often but cleaned it the least frequently. Based on obtained results, we discuss potential interventions that could help manage accidental IAS introductions at the national and EU levels.

Effect of introduction pathways on the invasion success of non-native plants along environmental gradients

Our understanding on the role of introduction pathways on plant invasions is incomplete because their interaction with other factors remains poorly studied. We contributed to filling this knowledge gap, by analysing temporal trends in pathway importance, pathway-specific differences in the invaded niche, and the effect of pathways on invasion success. We used the non-native flora of Catalonia (NE Spain) as a study system. The contribution of pathways to the non-native flora interacted with time: from before 1500 to the present, gardening replaced agriculture as the main donor of new plants, while the contribution of unintentional introductions fluctuated without a consistent trend. Among neophytes (plants introduced after 1500), introduction pathways influenced differences mainly in habitat type, and secondarily in elevation: natural habitats and high elevation promoted invasion by gardening plants over unintentionally introduced ones. These nuances were unrelated to interactions between environmental variables. Among neophytes, invasion success was unrelated to pathways and interactions between pathways and traits, but was positively related to minimum residence time: older introductions achieved greater area of occupancy, habitat range, and invaded climatic niche breadth. Our results suggest that non-native plants diversified their niches over time (1500-present), a process that resulted in similar area of occupancy and niche breadth across plants with different introduction pathways. This was accompanied by pathway-specific nuances in the type of invaded environmental conditions.

Seasonal abundance and trap comparisons of the invasive brown marmorated stink bug Halyomorpha halys (Hemiptera: Pentatomidae) adults from its native region

A challenging, yet fundamental part of initiating effective control measures against an invasive pest species is developing reliable means of monitoring the pest’s seasonal abundance. Halyomorpha halys, a polyphagous insect pest native to East Asia, has become a major economic threat to agricultural systems following unintentional introductions to North America, South America, and Europe. Research involving the seasonal phenology and monitoring attractant preferences of H. halys from its native range remain scarce. An 11-year collection of H. halys monitoring trap data from black light, incandescent light, and methyl (E, E, Z)-2, 4, 6-decatrienoate (MDT) lured traps from three locations in Kyoto, Japan was analyzed to fill gaps in knowledge relating to the native seasonal abundance and effectiveness of diferent trapping techniques for the pest. Due to a high amount of zero trap counts, a zero-inflated approach was taken to analyze the dataset. Overall, H. halys followed a bell-shaped population trend in Kyoto, with abundance peaking in the mid-summer. The attractant preference of H. halys varied slightly with the season, with black light traps producing to highest mean trap counts. The MDT lure traps generated the lowest mean trap counts, but displayed potential use in the reliable detection of early season H. halys. This work is expected to provide greater insight on H. halys in its native range and ultimately help refine existing management programs in invaded regions.

First case of introducing the exotic weevil Aclees taiwanensis Kôno, 1933 (Coleoptera: Curculionidae: Molytinae) in Poland

Aclees taiwanensis Kôno is an alien species in Europe, which originally came from Taiwan. In 2022, it was found for the first time in Poland as the result of an unintentional introduction from France, together with an ornamental specimen of Ficus microcarpa. In this paper, the history of the species’ appearance in Europe and its potential harmfulness to crops of ornamental plants are discussed.

Early detection of Youngia japonica (L.) DC. (Asteraceae) in São Miguel Island, Azores, Portugal

AbstractYoungia japonica (L.) DC. was recently discovered on the Azorean island of São Miguel. This species is a cosmopolitan herb that has been reported to be invasive in several regions of the world. It is unclear when and how this plant arrived in São Miguel, Azores. Nevertheless, we hypothesize that this is an unintentional and recent introduction. The populations are expanding in São Miguel, and action is needed to mitigate potential damage to native ecosystems.

Relatório temático sobre espécies exóticas invasoras no Brasil: sumário para tomadores de decisão

Abstract Biological invasions are one of the major threats to biodiversity and good quality of life, resulting from the translocation of species by human action. There are more than 500 alien species currently invading ecosystems in Brazil, particularly plants and fishes, while little is known about invasive microorganisms. Although invasive alien species are present in all ecosystems in the country, most have been recorded in habitats with greater human interference, such as urban and peri-urban areas, farmland, dams, reservoirs, ports, and canals. Historically, the southern and southeastern regions of Brazil have had more invasive alien species, but there has been an increase in the number of invasive alien species in the central-western and northern regions in recent decades. The ornamental trade of plants and fishes as well as the illegal pet trade of wild mammals and reptiles are some of the main pathways for invasive species introduction and spread in Brazil. Breeding and cultivation systems that allow escape to natural areas are a relevant route of species introductions in freshwater ecosystems, while unintentional introductions from shipping and infrastructure are of extreme concern in marine ecosystems. The negative impacts of invasive alien species on the biota mainly include changes in community structure and local decrease in native species richness, mediated by predation, competition, and ecosystem changes. Most negative impacts are recorded for intentionally introduced species, such as fishes and plants, but unintentional introductions have led to impacts on good quality of life, with associated costs and impacts on human health. The management of biological invasions faces challenges that need to be overcome, such as the lack of public knowledge about the impact of invasive alien species, the popular appeal of charismatic invasive species or those used by humans, and the use of controversial control techniques. However, successful experiences of eradication and control in terrestrial and marine ecosystems have been recorded, some of them involving public engagement in management actions. Recognizing the issue as a cross-cutting public policy and developing ongoing governance experiences are fundamental goals for the management of invasive alien species in Brazil.

Synsor: a tool for alignment-free detection of engineered DNA sequences.

DNA sequences of nearly any desired composition, length, and function can be synthesized to alter the biology of an organism for purposes ranging from the bioproduction of therapeutic compounds to invasive pest control. Yet despite offering many great benefits, engineered DNA poses a risk due to their possible misuse or abuse by malicious actors, or their unintentional introduction into the environment. Monitoring the presence of engineered DNA in biological or environmental systems is therefore crucial for routine and timely detection of emerging biological threats, and for improving public acceptance of genetic technologies. To address this, we developed Synsor, a tool for identifying engineered DNA sequences in high-throughput sequencing data. Synsor leverages the k-mer signature differences between naturally occurring and engineered DNA sequences and uses an artificial neural network to classify whether a DNA sequence is natural or engineered. By querying suspected sequences against the model, Synsor can identify sequences that are likely to have been engineered. Using natural plasmid and engineered vector sequences, we showed that Synsor identifies engineered DNA with >99% accuracy. We demonstrate how Synsor can be used to detect potential genetically engineered organisms and locate where engineered DNA is being introduced into the environment by analysing genomic and metagenomic data from yeast and wastewater samples, respectively. Synsor is therefore a powerful tool that will streamline the process of identifying engineered DNA in poorly characterized biological or environmental systems, thereby allowing for enhanced monitoring of emerging biological threats.

Clerodendrum bungei: Türkiye’de park ve bahçeler dışında çok sayıda yeni kaydı tespit edilen bir süs bitkisi

Clerodendrum bungei Steud. (Lamiaceae) is a deciduous shrub occurs both within its native Asian range and beyond to temperate and tropical regions around the world as a result of both unintentional and intentional introductions for ornamental uses. Although it was listed as an ornamental plant in parks and gardens of Türkiye, this paper presents a list of 52 record including 46 new records of C. bungei outside parks and gardens of Türkiye. The new list includes 11 records from Artvin, 10 records from Rize, 8 records from Trabzon, 14 records from Giresun, 3 records from Ordu and 1 record from Samsun. The rapid increase in the number of new localities outside gardens and parks of Türkiye in the last 10 years shows that the species has been an invasive alien species in this region in the near future. So, it will outcompete native plant species and impact habitat values, thus it is important to closely monitor the populations outside parks and garden in this region and should take the necessary precautions by local farmers and administrations.

THE GIANT WATER BUG LETHOCERUS (HEMIPTERA HETEROPTERA BELOSTOMATIDAE) IS SPREADING IN ITALY: THE FIRST RECORD FOR CAMPANIA

Lethocerus patruelis (Stål, 1854) is the only member of the Belostomatidae family in Europe. During the last decades, records of this giant water bug have become frequent in south-eastern Italy, but with no evidence about its origin (man-mediated unintentional introduction or a natural westward spread). The status of this species in Italy is still uncertain, but the man-mediated unintentional introduction seems the most probable, even through multiple introductions. The first record of Lethocerus cf. patruelis for the Campania region (the first one on the Tyrrhenian side of Italy) is here reported, suggesting the already registered tendency of this species to expand, at least in Europe. Several topics need to be evaluated, in the light of its status in Italy and its management. Key Words: aquatic insect; distribution; Heteroptera; Nepomorpha; new record.

Germany’s first Action plan on the pathways of invasive alien species to prevent their unintentional introduction and spread

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

Phylogeography and genetic diversity of the Japanese mud shrimp Upogebiamajor (Crustacea, Decapoda, Upogebiidae): Natural or anthropogenic dispersal?

Upogebiamajor (De Haan, 1841) is known for forming huge burrows in sandy, intertidal areas that can extend to depths of over 2 m. Despite its widespread distribution in East Asia and Russia, the genetic relatedness of its regional populations remains uncertain, likely owing to difficulties in specimen collection. Therefore, to appraise the phylogeographic patterns, genetic diversity, and morphological variety of U.major, the mitochondrial DNA of specimens collected from Japan, Korea and China were subjected to molecular phylogenetic analyses of COI genes, alongside morphological assessment. As a result, we discovered four principal groups; of these, Group 1 consisted predominantly of Japanese specimens, while Groups 3 and 4 were interpreted as having originated from the continent. Group 2 exhibited genetic segregation from both continental and Japanese descent. Group 1 mostly comprising Japanese specimens implies that the planktonic larvae of U.major were disseminated north and south by ocean currents encompassing the Japanese archipelago. In contrast, individuals probably originating from the continent were discovered in Lake Notoro, Hokkaido and Matsukawa-ura, Fukushima in northeastern Japan, indicating possible introduction from the continent through ocean currents or unintentional introduction with other organisms imported. Additionally, one of the specimens collected from Matsukawa-ura exhibited significant genetic and morphological differences from other specimens, suggesting the possibility of being a subspecies. The outcomes of this study not only offer valuable insights into the origins of distribution of U.major but also introduce a novel challenge of assessing the coexistence of two routes: natural and anthropogenic dispersion.

Global flows of insect transport and establishment: The role of biogeography, trade and regulations

AbstractAimNon‐native species are part of almost every biological community worldwide, yet numbers of species establishments have an uneven global distribution. Asymmetrical exchanges of species between regions are likely influenced by a range of mechanisms, including propagule pressure, native species pools, environmental conditions and biosecurity. While the importance of different mechanisms is likely to vary among invasion stages, those occurring prior to establishment (transport and introduction) are difficult to account for. We used records of unintentional insect introductions to test (1) whether insects from some biogeographic regions are more likely to be successful invaders, (2) whether the intensity of trade flows between regions determines how many species are intercepted and how many successfully establish, and (3) whether the variables driving successful transport and successful establishment differ.LocationCanada, mainland USA, Hawaii, Japan, Australia, New Zealand, Great Britain, South Korea, South Africa.MethodsTo disentangle processes occurring during the transport and establishment stages, we analysed border interceptions of 8199 insect species as a proxy for transported species flows, and lists of 2076 established non‐native insect species in eight areas. We investigated the influence of biogeographic variables, socio‐economic variables and biosecurity regulations on the size of species flows between regions.ResultsDuring transport, the largest species flows generally originated from the Nearctic, Panamanian and Neotropical regions. Insects native to 8 of 12 biogeographic regions were able to establish, with the largest flows of established species on average coming from the Western Palearctic, Neotropical and Australasian/Oceanian regions. Both the biogeographic region of origin and trade intensity significantly influenced the size of species flows between regions during transport and establishment. The transported species richness increased with Gross National Income in the source country, and decreased with geographic distance. More species were able to establish when introduced within their native biogeographic region.Main ConclusionsOur results suggest that accounting for processes occurring prior to establishment is crucial for understanding invasion asymmetry in insects, and for quantifying regional biosecurity risks.

The concept and nature of the occurrence of doctrinal legal errors

The concept and nature of the occurrence of doctrinal legal errors

Behavioral interventions to reduce unintentional non-native plants introduction: Personal factors matter

To reduce biodiversity loss, human behavioral change is crucial. However, there has been a significant paucity of effective conservation behavioral interventions, which help establish evidence-based policymaking and lead to the understanding of intervention effectiveness mediators. This study focused on preventing the unintentional introduction of non-native species by examining the effectiveness of four behavioral interventions using an experiment and a questionnaire. The interventions sought to induce footwear cleaning, which reduces non-native species introduction via footwear, at a cleaning station. Responses were considerably heterogeneous across interventions—that is, nudging visitors toward the cleaning station using foot-stamps placed on the ground had the largest impact, while providing procedural knowledge also had a significant effect. Further, the impact of these two interventions differed greatly depending on the degree of individuals' knowledge and/or personalized involvement in the unintentional introduction process. To maximize the impact of and improve interventions, we suggest accounting for the personal factors of the targeted individuals.

FINDING OF THE WESTERN CONIFER SEED BUG LEPTOGLOSSUS OCCIDENTALIS (HETEROPTERA: COREIDAE) IN THE VORONEZH NATURE RESERVE (CENTRAL RUSSIA)

In the south-east of the forest area of the Voronezh Nature Reserve (quarter 541, central estate, 51°52ʹ33ʺ N; 39°39ʹ09ʺ E,) outside on the window of the main administrative building, a female of the western conifer seed bug Leptoglossus occidentalis (Heidemann, 1910) was recorded on November 19, 2021. It is an actively spreading species native to North America, where it damages seed plantations of coniferous trees and shrubs reducing significantly their seed productivity. This finding is the northernmost in the European part of Russia (the nearest location is 40 km to the south of the reserve, on the outskirts of Voronezh). This is probably the result of unintentional introduction by motor vehicle (there are three parking lots for tourist buses and cars of visitors next to the main administrative building of the reserve).