Alien Species Research Articles

Trophic positioning among native and non-indigenous species in the eastern Mediterranean Sea

The substantial influx of non-indigenous species (NIS) into the eastern Mediterranean Sea from the Suez Canal has prompted questions about the mechanisms enabling their establishment and the resulting impacts on native species. We focus on the trophic level dynamics of the dominant native red mullet (Mullus barbatus) and the four NIS Pomadasys stridens, Upeneus moluccensis, U. pori, and Parupeneus forsskali. Using various methods, including trophic level estimations, intestine length analysis, and monthly trophic level variations, we assessed their trophic positions and flexibility. The results indicate that compared to M. barbatus, P. stridens occupies a lower trophic level due to its omnivorous nature, potentially facilitating its biomass increase. This lower trophic position is further supported by its lengthy intestine relative to size. Conversely, U. moluccensis, U. pori, and P. forsskali position themselves consistently at higher trophic levels than M. barbatus. Monthly trophic level variations suggest temporal dietary changes, which point to seasonal impacts on NIS success. M. barbatus’s resilience, including its preference for polychaetes, may explain its sustained dominance amid competition. This study sheds light on NIS-native species coexistence, further suggesting that NIS success could stem from exploitation of vacant niches and adaptation to new food sources.

Urban Biodiversity Index for Trees: A Climate Adaptation Measure for Cities Based on Tree Inventories

A historically large percentage of the world’s population has moved to urban areas in the past few decades, causing various negative effects for the environment, such as air, noise, water, and light pollution; land degradation; and biodiversity loss. Under the current climate crisis, cities are anticipated to play an essential part in adaptation strategies to extreme atmospheric events. This study aims at developing indicators at an urban scale that can highlight adaptation progress by investigating relevant data (especially in situ) and statistics at a pan-European level in support of the EU’s strategy for adapting to the impacts of climate change. The proposed indicator, Urban Biodiversity Indicator for Trees (UBI4T), which can be derived from city tree inventories, assesses one essential component of urban biodiversity by computing the proportion of native, alien, invasive, and toxic tree species spatially across a city. According to our findings (applying the UBI4T for Amsterdam and exploring its policy potential for Barcelona), the UBI4T can offer crucial information for decision and policy makers, as well as stakeholders of a city, with the aim of conducting dedicated and effective strategic initiatives to restore, improve, and protect nature in the urban environment, thus contributing to adaptation and resilience to extreme atmospheric events in cities.

Potential of Polar Lipids Isolated from the Marine Sponge Haliclona (Halichoclona) vansoesti against Melanoma.

Marine sponges represent a good source of natural metabolites for biotechnological applications in the pharmacological, cosmeceutical, and nutraceutical fields. In the present work, we analyzed the biotechnological potential of the alien species Haliclona (Halichoclona) vansoesti de Weerdt, de Kluijver & Gomez, 1999, previously collected in the Mediterranean Sea (Faro Lake, Sicily). The bioactivity and chemical content of this species has never been investigated, and information in the literature on its Caribbean counterpart is scarce. We show that an enriched extract of H. vansoesti induced cell death in human melanoma cells with an IC50 value of 36.36 µg mL-1, by (i) triggering a pro-inflammatory response, (ii) activating extrinsic apoptosis mediated by tumor necrosis factor receptors triggering the mitochondrial apoptosis via the involvement of Bcl-2 proteins and caspase 9, and (iii) inducing a significant reduction in several proteins promoting human angiogenesis. Through orthogonal SPE fractionations, we identified two active sphingoid-based lipid classes, also characterized by nuclear magnetic resonance and mass spectrometry, as the main components of two active fractions. Overall, our findings provide the first evaluation of the anti-cancer potential of polar lipids isolated from the marine sponge H. (Halichoclona) vansoesti, which may lead to new lead compounds with biotechnological applications in the pharmaceutical field.

UAV telephotography elucidates floristic variability and beta diversity of island cliffs under grazing interventions

Cliffs contain one of the least known plant communities, which has been overlooked in biodiversity assessments due to the inherent inaccessibility. Our study adopted the unmanned aerial vehicle (UAV) with the telephoto camera to remotely clarify floristic variability across unreachable cliffs. Studied cliffs comprised 17 coastal and 13 inland cliffs in Gageodo of South Korea, among which 9 and 5 cliffs were grazed by the introduced cliff-dwelling goats. The UAV telephotography showed 154 and 166 plant species from coastal and inland cliffs, respectively. Inland cliffs contained more vascular plant species (P < 0.001), increased proportions of fern and woody species (P < 0.05), and decreased proportion of herbaceous species (P < 0.001) than coastal cliffs. It was also found that coastal and inland cliffs differed in the species composition (P < 0.001) rather than taxonomic beta diversity (P = 0.29). Furthermore, grazed coastal cliffs featured the elevated proportions of alien and annual herb species than ungrazed coastal cliffs (P < 0.05). This suggests that coastal cliffs might not be totally immune to grazing if the introduced herbivores are able to access cliff microhabitats; therefore, such anthropogenic introduction of cliff-dwelling herbivores should be excluded to conserve the native cliff plant communities.

Invasive species or legal alien? Confrontation and controversy in protecting sabras in Israel

AbstractIn an era marked by heightened globalization and climate crisis, the proliferation of alien or invasive species has emerged as a critical issue. This article delves into the contentious debates surrounding strategies for addressing these species, offering insights into divergent visions of “environmental futures” and the intricate interplay of concern, risk, and power relations in the Anthropocene. Through ethnographic research, the article scrutinizes discourses and practices related to the preservation of sabras, recent immigrants from the Americas that have become emblematic in Israel/Palestine, symbolizing a shared connection to the land for Jews and Palestinians. The primary focus is on efforts to protect sabras from an invasive insect threat, which involves introducing a “natural enemy” to combat the intruder, sparking controversy among scientists and stakeholders. By employing the concept of “Anthropocene concern,” the article unveils the anxieties of various actors regarding nonhuman entities and demonstrates how these perceptions drive human actions or inaction. Despite the temptation to associate the political struggle only with the Israeli/Palestinian conflict, the article shows the importance of analyzing the political–scientific struggle around the appropriate approach to dealing with invasive species and how emotions, politics, and science are intertwined at different levels, requiring careful analysis and interpretation.

Investigation of landscape risk factors for the recent spread of varroa mite (Varroa destructor) in European honeybee (Apis mellifera) colonies in New South Wales, Australia.

In June 2022, an exotic pest of the European honeybee (Apis mellifera), the varroa mite (Varroa destructor), was detected in surveillance hives at the Port of Newcastle, New South Wales (NSW). Previously, Australia remained the only continent free of the varroa mite. In September 2023, the National Management Group decided to shift the focus of the response from eradication to management. It is estimated that the establishment of varroa mite in Australia could lead to more than $70 million in losses each year due to greatly reduced pollination services. Currently, there are no reported studies on the epidemiology of varroa mite in NSW because it is such a recent outbreak, and there is little knowledge of the factors associated with the presence of V. destructor in the Australian context. We sourced publicly available varroa mite outbreak reports from June 22 to December 19, 2022, to determine if urbanization, land use, and distance from the incursion site are associated with the detection of varroa mite infestation in European honeybee colonies in NSW. The outcome investigated was epidemic day, relative to the first detected premises (June 22, 2022). The study population was comprised of 107 premises, which were declared varroa-infested. The median epidemic day was day 37 (July 29, 2022), and a bimodal distribution was observed from the epidemic curve, which was reflective of an intermittent source pattern of spread. We found that premises were detected to be infected with varroa mite earlier in urban areas [median epidemic day 25 (July 17, 2022)] compared to rural areas [median epidemic day 37.5 (July 29, 2022)]. Infected premises located in areas without cropping, forests, and irrigation were detected earlier in the outbreak [median epidemic days 23.5 (July 15, 2022), 30 (July 22, 2022), and 15 (July 7, 2022), respectively] compared to areas with cropping, forests, and irrigation [median epidemic days 50 (August 11, 2022), 43 (August 4, 2022), and 47 (August 8, 2022), respectively]. We also found that distance from the incursion site was not significantly correlated with epidemic day. Urbanization and land use are potential factors for the recent spread of varroa mite in European honeybee colonies in NSW. This knowledge is essential to managing the current varroa mite outbreak and preventing future mass varroa mite spread events.

A host, a parasite, and a predator: the dynamics of successive invasions in the eastern Mediterranean

The eastern Mediterranean shelf ecosystem has been profoundly disrupted by the influx of invasive alien species introduced through the Suez Canal. Yet, the role of retaining or shedding co-evolved parasitofauna in the success of the invading biota has been scarcely monitored, with the exception of the lesser swimming crab Charybdis (Archias) longicollis Leene, 1938 parasitized by the rhizocephalan Heterosaccus dollfusi Boschma, 1960. Host size, sex ratio, prevalence of ovigerous females, parasitization, and multiple parasitization, were studied over 30 years to determine long-term host-parasite variation. Our results reveal that C. longicollis crabs have shifted their temporal activity pattern shortly following the domination of their preferred depth niche by the invasive diurnal predator, the silver-cheeked toadfish Lagocephalus sceleratus (Gmelin, 1789), which preferentially feeds on C. longicollis locally. A unique set of predator-host-parasite interactions among three successive Erythraean invasive aliens is considered herein.

Smartphone-Based Citizen Science Tool for Plant Disease and Insect Pest Detection Using Artificial Intelligence

In recent years, the integration of smartphone technology with novel sensing technologies, Artificial Intelligence (AI), and Deep Learning (DL) algorithms has revolutionized crop pest and disease surveillance. Efficient and accurate diagnosis is crucial to mitigate substantial economic losses in agriculture caused by diseases and pests. An innovative Apple® and Android™ mobile application for citizen science has been developed, to enable real-time detection and identification of plant leaf diseases and pests, minimizing their impact on horticulture, viticulture, and olive cultivation. Leveraging DL algorithms, this application facilitates efficient data collection on crop pests and diseases, supporting crop yield protection and cost reduction in alignment with the Green Deal goal for 2030 by reducing pesticide use. The proposed citizen science tool involves all Farm to Fork stakeholders and farm citizens in minimizing damage to plant health by insect and fungal diseases. It utilizes comprehensive datasets, including images of various diseases and insects, within a robust Decision Support System (DSS) where DL models operate. The DSS connects directly with users, allowing them to upload crop pest data via the mobile application, providing data-driven support and information. The application stands out for its scalability and interoperability, enabling the continuous integration of new data to enhance its capabilities. It supports AI-based imaging analysis of quarantine pests, invasive alien species, and emerging and native pests, thereby aiding post-border surveillance programs. The mobile application, developed using a Python-based REST API, PostgreSQL, and Keycloak, has been field-tested, demonstrating its effectiveness in real-world agriculture scenarios, such as detecting Tuta absoluta (Meyrick) infestation in tomato cultivations. The outcomes of this study in T. absoluta detection serve as a showcase scenario for the proposed citizen science tool’s applicability and usability, demonstrating a 70.2% accuracy (mAP50) utilizing advanced DL models. Notably, during field testing, the model achieved detection confidence levels of up to 87%, enhancing pest management practices.

Assessing grazing of Rugulopteryx okamurae (Ochrophyta) by the sea urchin Paracentrotus lividus (Echinodermata): a prospect for the biocontrol of the alien species?

ABSTRACT Rugulopteryx okamurae is an invasive non-indigenous species (NIS) of marine alga present in the benthic communities of the Strait of Gibraltar, where it has colonized most of the coast triggering ecological, economic and social consequences. The purple sea urchin Paracentrotus lividus is a generalist herbivore with potential to provide resistance to this NIS. Two experiments were carried out to determine if (i) P. lividus consumes R. okamurae under laboratory conditions, (ii) to assess its grazing preferences when this NIS is offered together with the native Ulva sp. and (iii) to find biochemical tissue markers related to R. okamurae ingestion. In the first experiment, sea urchins fed with R. okamurae, Ulva sp. or both diets were evaluated in groups for two months. Ingestion, food preference, growth and survival were assessed. In the second one, the same specimens from the R. okamurae and mixed diets were used to analyse their individual preferences, ingestion rates, growth and fatty acid profiles during another two months. Ingestion rates showed that sea urchins accepted the NIS R. okamurae as food under laboratory conditions, increasing its intake after a long exposure period. The electivity values for R. okamurae also increased when P. lividus was exposed to this alga for a long time. Regarding the fatty acids profile of tissues, the results showed that intestinal arachidonic acid (ARA, 20:4n-6) clearly differentiates sea urchins fed with R. okamurae from those fed with the mixed diet. ARA also appeared to be related to the feeding preferences, highlighting this fatty acid as a reliable marker of R. okamurae ingestion. Further research is needed in order to determine P. lividus feeding behaviour and its role as a biocontrol species in the areas invaded by R. okamurae.

Late Pleistocene to Holocene vegetation changes in southeastern Patagonia (49° S): landscape changes related to disturbances

ABSTRACTSoutheastern Patagonia's (49° S) post‐glacial history inferred from high Andean lake sediments provides new insights regarding Late Pleistocene and Holocene vegetation dynamics at the eastern margin of the Southern Patagonian Icefield. The fossil records of pollen, charcoal and geochemical data from tephra layers from Laguna Chiquita and Laguna Gemelas Este were analysed to reveal past landscape dynamics related to vegetation changes, fire and volcanic events from ca. 15 200 cal a bp to the present. Nothofagus forest expanded over shrubland communities sometime between 15 200 and 4600 cal a bp, along with at least three disturbance sources related to the volcanic eruptions of Lautaro, Aguilera and Hudson, important local fire episodes, and neoglacial advances. Major charcoal deposition reveals moderate fire activity during the Late Pleistocene related to an open landscape characterised by a grass/shrub steppe. Local glacier advances may have affected the Laguna Gemelas Este sedimentation. Tephra deposition events do not correlate to vegetation changes inferred from the Laguna Gemelas Este and Laguna Chiquita pollen records. Late Holocene eastern Andean forest changes and fire activity at 49° S match other southern palaeoenvironmental records (50–52° S) suggesting that changes in the Southern Westerly Wind latitudinal position and intensity drove major palaeovegetation and fire dynamics before the European settlement. In the last centuries, fire and vegetation changes have been closely related to an increase in local ignition sources and the introduction of alien species.

Cory's Shearwater (Calonectris borealis): Exploring Normal Head Anatomy through Cross-Sectional Anatomy, Computed Tomography and Magnetic Resonance Imaging.

Cory's shearwater, or Calonectris borealis, stands out as a symbolic figure in the world of seabirds, playing a crucial role in marine ecosystems globally. Belonging to the Procellariidae family, it is singularized by its imposing wingspan and intricate migration patterns connecting it to various regions from the North Atlantic to the Pacific. Its role in the marine food chain, specialized diet and adaptation for nesting in the Canary Archipelago underscore its ecological importance. However, Cory's shearwater also faces important threats, such as the invasion of foreign species, highlighting the need for its conservation. Among the conservation issues, studies on its biology, the main threats it faces and its normal anatomy are essential to preserve marine biodiversity. Additionally, a variety of imaging techniques, such as computed tomography and magnetic resonance, facilitates the understanding of the bird's neuroanatomy and opens future research possibilities in comparative neuroscience. Moreover, this approach proves particularly relevant given the increasing attention these seabirds receive in environments such as zoos, rehabilitation centers and their natural habitat, where veterinarians play a crucial role in their care and well-being.

Alien Trees and Shrubs with the Complements Saksamaa (Germany) and Saksa (German) in Early Written Language and Folklore

The study of alien species has become more and more relevant today. In particular, the influence of alien species on the local nature is studied, but more and more studies have also begun to appear on how alien species affect the local language and culture. In this article, we took a look at non-native trees and shrubs that have been called “Saksamaa” and “Saksa” [German]. Germany was synonymous with foreign countries in early literature. We investigated the motives behind the names given to these species, how long they were in circulation and how these names were later replaced. For this purpose, we studied lexicons, archival texts and historical literature. „German“ complemented plant names are most common in Estonian and Finnish – with fir, beech, larch, elder, Persian walnut tree, poplar, Swedish whitebeam and false spiraea coinciding. The prevalence of plant names can be divided into three: a) names found only in the early written word, which are absent in the oral tradition; b) vernacular plant names with the suffix “German” which were entered into dictionaries and supported by official terminology; c) individual fop names with the suffix “German” collected from the people. Alien species that were planted as fruit trees, ornamental trees, medicinal plants and forest trees were called by these names, but imported pharmaceutical drugs, fruits and wood were also called “German”. Mainly, non-ntive species were named after a local tree, to which “German” was added in front of the name. Later, those names were either replaced by adaptations of German plant names or new Estonian plant names were created. Several trees could be called by one name. For example, larches, firs and alien spruce species, which differed from the local spruce by the silvery colour of their needles, have been called the “German spruce”. In the 17th and 18th centuries, all foreign trees that were frost-resistant could be called “German trees.” Back in the 20th century, people spontaneously called foreign trees that were different from domestic trees by the names of “German”.

Vascular flora of the isthmus of Feniglia (southern Tuscany, Italy)

We studied the vascular flora of the isthmus of Feniglia, a Nature Reserve in southern Tuscany stretching between the Italian Peninsula and Mt. Argentario. Since the nineteenth century, the area has undergone significant environmental modifications due to intensive grazing and deforestation. Later, rehabilitation interventions were carried out, including reforestation and planting of dune species, making it an interesting protected area to study for its botanical aspects. Therefore, we aim to compile the floristic inventory of this distinctive Mediterranean area by integrating old and new data. The checklist comprises 502 specific and subspecific taxa of vascular plants. The life-form spectrum shows a predominance of therophytes, followed by hemicryptophytes. The chorological spectrum highlights the dominance of Mediterranean species, followed by Euromediterranean and Eurasian species. The presence of 15 species of regional importance, 3 species of the Italian red list and 3 Italian endemics (Ornithogalum exscapum Ten., Limonium multiforme Pignatti, Linaria purpurea (L.) Mill.) is noteworthy. Despite the environmental changes undergone in this area, our study reports the presence of remarkable species, including rare ones such as Atriplex littoralis L., Ruppia spiralis L. ex Dumort., and species at their distribution margin in the Italian Peninsula, such as Staphisagria macrosperma Spach, Juncus sorrentinoi Parl. and Maresia nana (DC.) Batt. Additionally the presence of 26 alien species, of which 15 are invasive, 9 naturalized and 2 casual, indicates a relatively low presence of alien species. Notwithstanding the significant environmental changes that the Feniglia isthmus has experienced in the last century and the high tourist pressure during the summer, the presence of the protected area suggested the effectiveness and benefits of such a form of protection for plant diversity.

Rapid and Portable Presumptive Loop‐Mediated Isothermal Amplification Assays for the Detection of the Invasive Corn Snake (Pantherophis guttatus)

ABSTRACTThe exotic pet trade is a major pathway for the introduction, establishment, and spread of novel invasive alien species. Reptiles are common in the exotic pet trade and are prominent invasive alien vertebrate species that have dire impacts if allowed to establish. The North American corn snake (Pantherophis guttatus) is particularly common in the international pet trade and has been identified as a vertebrate pest priority species in Australia due to widespread climate suitability and prevalence in pre‐ and post‐border seizure records. Consequently, rapid, and presumptive post‐border biosecurity detection is essential to prevent its establishment and spread. Loop‐mediated isothermal amplification (LAMP) is an emerging biosecurity tool that has shown promise for rapid detection of several high‐risk species. We developed two LAMP assays for the detection of P. guttatus, validated against: synthetic DNA; DNA extracted from snap‐frozen tissue, and shed skins; and then compared their performance for the detection of trace DNA collected from swabs of glass tanks post reptile presence. Our results include laboratory optimization and assessment of two mobile devices for in‐field integration (Franklin Real‐Time PCR Thermocycler, Biomeme, USA, and Genie III, Optigene, UK). The results indicate that LAMP is a viable biosecurity tool, with DNA detection possible for a range of sample types in a total of c.30 min, when including a rapid extraction step (8 min). Herein, we provide tools for rapid, presumptive detection of the North American corn snake from trace DNA samples in Australian biosecurity and wildlife compliance settings.

First record of stone moroko (Pseudorasbora parva), an invasive alien fish species, in water bodies of urban green areas in Poland

Abstract Invasive alien species are currently a major ecological problem. One such species is stone moroko, Pseudorasbora parva (Gobionidae), which has only been found to date in natural or agricultural water bodies (lakes, rivers and streams, carp ponds). Therefore, the current study is the first description of stone moroko in urban green areas (Warsaw, Poland). The fish were caught with a hydrobiological net. Four catches were conducted in ponds located in Morskie Oko Park (pond 1) and the Saxon Garden (pond 2) – two in fall and two in the spring, while two spring catches were conducted in Dolinka Służewska Park (stream). The population in pond 2 apparently survived the winter, and the fish caught in June displayed visible signs of sexual dimorphism and were significantly larger (average body mass: 1648 ± 1123 mg; range: 460–6090 mg) than those caught in the pond in the two fall samplings (404 ± 122 mg; 154–729 mg). After recording substantial numbers of specimens in the fall, no fish were caught in pond 1 during either of the spring catches, while only a few moroko were caught in the stream in April (1212 ± 869 mg; 454–2901 mg) and none were caught in June. Throughout the study, 59 specimens were caught in pond 1, 74 in pond 2, and 7 in the stream.

Animals, Wonder, and “Order Trouble” during the Jesuit Mission to Japan

When Jesuit missionaries began arriving in Japan in the sixteenth century, they brought not only a new religion, Christianity, but also several domestic and exotic animals. Not only did these animals provoke feelings of curiosity and wonder, but they became a site of epistemic contestation between Christian and Buddhist views on human‐animal relations. In Buddhist thought, humans and animals were conceived of as interrelated, as both were thought to be trapped in an endless cycle of death and rebirth. On the other hand, in Christian thought, humans and animals were stratified according to Aristotelian hierarchies, according to which the former were viewed as superior to the latter. After the Jesuits arrived in Japan, it soon became clear that their proselytes' pre‐existing modes of relating to and classifying the natural world would need to be converted to Aristotelian ones in order to propagate a Christian way of life. Thus, animals became a central part of Jesuit evangelism. Many of these creatures were deployed as tribute gifts, which altered the emotional landscape between the European and Japanese humans who used them as a buffer. This paper explores how animals, wonder, and religious epistemologies intersected to transform Japanese Christian attitudes towards animals during the Jesuit Mission to Japan.

Can sustainable biocommerce continue to support conservation, or will the captive breeding of offspring be its Achilles heel?

Abstract The trade in high‐value natural resources, particularly exotic plants and animals (henceforth biocommerce), can lead to both positive and negative impacts on wild populations. The exotic plant and animal hobbies are highly organized with internal cultures that are often poorly understood by non‐members; however, understanding them is of central importance for biocommerce with both direct and indirect consequences for the conservation of wild populations. Growing international demands for exotic species leaves simple questions related to the economics of biocommerce unexplored. The long‐term success of biocommerce businesses requires constant income, meaning they obtain and retain significant market proportions. Some biocommerce products can be reproduced by hobbyists and undercut business efforts based on sustainably produced exports. We analyse a test case in Neotropical poison frogs where sustainable biocommerce is burgeoning, yet (export‐based) businesses face direct market competition from the offspring produced within the countries, which receive their exports, and therefore are forced to rely on fervent customer support. Solution: We survey customers' behaviours where we find different classes of consumers, which differ in where they place higher values within the hobby. By taking into account these different classes, we gain insights and potential solutions to promote the stability of this unique type of biocommerce.

First record of Mytilisepta virgata (Bivalvia: Mytilidae) in Russian waters

Mytilisepta virgata was first collected as empty shells attached to plastic debris in south-western part of Peter the Great Bay (Sea of Japan), near Russian-Korean border. This species may be considered as a potentially non-indigenous species in Russian waters due to coastal warming, influence of warm-water currents and its presence in North Korean waters. A description, illustrations, data on distribution and ecology and taxonomic comments are provided.

Food web collapse and regime shift following goldfish introduction in permanent ponds.

In a global context of invasive alien species (IAS), native predators are often eradicated by functionally different IAS, which may induce complex cascading consequences on ecosystem functioning because of the key role predators play in structuring communities and stabilizing food webs. In permanent ponds, the most abundant freshwater systems on Earth, global human-mediated introductions of alien omnivores such as the pet trade goldfish are driving broad-scale patterns of native predators' exclusion, but cascading consequences on food web structure and functioning are critically understudied. We compared food webs of naturally fishless ponds versus ponds where dominant native predators (newts) had been extirpated by invasive goldfish within the last decade. Integrating community-wide isotopic, taxonomic and functional traits approaches, our study reveals that pond food webs collapsed in both vertical and horizontal dimensions following goldfish introduction and the associated exclusion of native predators. Consumer taxonomic diversity was drastically reduced, essentially deprived of amphibians as well as predatory and mobile macroinvertebrates to the profit of burrowing, lower trophic level consumers (detritivores). Changes in community structure and function underlined a regime shift from a macrophyte-dominated system mainly characterized by benthic primary production (periphyton), to a macrophyte-depleted state of ponds hosting communities mainly associated with phytoplankton primary production and detritus accumulation, with higher tolerance to eutrophication and low dissolved oxygen concentration. Results underline major impacts of widely introduced omnivores such as the goldfish on the functioning of pond ecosystems with potentially dramatic consequences on the key ecosystem services they deliver, such as global biodiversity support or water quality improvement. They also shed light on the key role of submerged aquatic vegetation in supporting diverse communities and complex food webs in shallow lentic systems and call for urgent consideration of threats posed by IAS on ponds' ecosystems by managers and policymakers.

Impacts of climate change on the potential distribution of Pulex simulans and Polygenis gwyni.

Pulex simulans and Polygenis gwyni are vectors of many flea-borne diseases. They were widely recorded in the United States and Mexico between 1970 and 2000. Maximum entropy models were used to explore the habitats of both fleas under different climate scenarios to provide the scientific basis for the surveillance and control of flea-borne diseases. We screened climate variables by principal component analysis and Pearson's correlation test and evaluated model performance by ROC curve. ArcMap was used to visualize expressions. Under current climatic conditions, the medium and highly suitable areas for P. simulans are estimated to be 9.16 × 106 km2 and 4.97 × 106 km2, respectively. These regions are predominantly located in South America, along the Mediterranean coast of Europe, the southern part of the African continent, the Middle East, North China, and Australia. For P. gwyni, the medium and highly suitable areas under current climatic conditions are approximately 4.01 × 106 and 2.04 × 106 km2, respectively, with the primary distribution in North China extending to the Himalayas, near the Equator in Africa, and in a few areas of Europe. Under future climate scenarios, in the SSP3-7.0 scenario for the years 2081-2100, the area of high suitability for P. simulans is projected to reach its maximum. Similarly, in the SSP2-4.5 scenario for 2061-2080, the area of high suitability for P. gwyni is expected to reach its maximum. Under global climate change, there is a large range in the potential distribution for both fleas, with an overall upward trend in the area of habitat under future climate scenarios. Governments should develop scientific prevention and control measures to prevent the invasive alien species flea.