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Cutting is frequently used to control invasive species, but the ability of plants to produce stump sprouts is little studied, even though it has strong consequences on the efficiency of this management, and a structural effect on ecosystems. Here we have studied the intraspecific variability of resprouting capacities of the common gorse, (Ulex europaeus) by comparing regions of its native and invaded areas. We conducted a comparative study in an experimental garden between two invaded regions (Reunion, New Zealand) and two native regions (Scotland, Brittany). Results show that (1) regrowth is mainly governed by the basal architecture of individuals (2) there are differences in resprouting capacity depending on the geographic regions, but no clear trend within native and invasive areas (3) life-history traits linked with resprouting capacity also vary depending on geographic regions. These results show large intraspecific variation in the resprouting capacity of gorse, and provide guidance for the management of gorse in invaded areas.; La coupe est fréquemment utilisée pour contrôler les espèces envahissantes, mais la capacité des plantes à produire des rejets de souche est peu étudiée alors qu’elle a de fortes conséquences sur l'efficacité de cette gestion, et un effet structurel sur les écosystèmes. Ici, nous avons étudié la variabilité intraspécifique des capacités de repousse de l'ajonc commun, (Ulex europaeus) en comparant des régions de ses zones d'origine et envahies. Nous avons mené une étude comparative dans un jardin expérimental entre deux régions envahies (Réunion, Nouvelle-Zélande) et deux régions natives (Ecosse, Bretagne). Les résultats montrent que (1) la repousse est principalement gouvernée par l'architecture basale des individus (2) il existe des différences dans la capacité de repousse selon les régions géographiques, mais pas de tendance claire entre des régions natives et envahies (3) les traits d'histoire de vie liés à la capacité de repousse dépendent de la région. Ces résultats montrent une grande variation intraspécifique dans la capacité de repousse de l'ajonc, et fournissent des indications pour la gestion de l'ajonc dans les zones envahies.

International audience; Biological invasions can dramatically impact natural ecosystems and human societies. However, although knowledge of the economic impacts of biological invasions provides crucial insights for efficient management and policy, reliable syntheses are still lacking. This is particularly true for low income countries where economic resources are insufficient to control the effects of invasions. In this study, we relied on the recently developed "InvaCost" database – the most comprehensive repository on the monetised impacts of invasive alien species worldwide – to produce the first synthesis of economic costs of biological invasions on the African continent. We found that the reported costs of invasions ranged between US$ 18.2 billion and US$ 78.9 billion between 1970 and 2020. This represents a massive, yet highly underestimated economic burden for African countries. More alarmingly, these costs are exponentially increasing over time, without any signs of abatement in the near future. The reported costs were mostly driven by damage caused by invaders rather than expenses incurred for management. This trend was highly skewed towards a few regions (i.e. Southern and Eastern Africa) and activity sectors (i.e. agriculture) and incurred by a small number of invasive taxa (i.e. mainly three insect pests: Chilo partellus , Tuta absoluta , Spodoptera frugiperda ). We also highlight crucial, large gaps in current knowledge on the economic costs of invasions that still need to be bridged with more widespread research effort and management actions across the continent. Finally, our study provides support for developing and implementing preventive measures as well as integrated post-invasion management actions at both national and regional levels. Considering the complex societal and economic realities in African countries, the currently neglected problem of biological invasions should become a priority for sustainable development.; Les invasions biologiques peuvent avoir un impact considérable sur les écosystèmes naturels et les sociétés humaines. Cependant, bien que les connaissances sur les impacts économiques des invasions biologiques fournissent des informations cruciales en termes de gestion, des synthèses récentes et fiables font encore défaut. Cela est particulièrement vrai pour les pays à faible revenu où les ressources économiques sont insuffisantes pour contrôler les effets des invasions. Dans cette étude, nous nous sommes appuyés sur la base de données "InvaCost" développée récemment - le référentiel le plus complet sur les impacts monétaires des espèces exotiques envahissantes dans le monde - pour produire la première synthèse des coûts économiques des invasions biologiques sur le continent africain. Nous avons constaté que les coûts déclarés des invasions varient entre 18,2 milliards de dollars américains (USD) et 78,9 milliards USD entre 1970 et 2020. Cela représente une charge économique énorme, mais encore très sous-estimée, pour les pays africains. Plus alarmant encore, ces coûts augmentent de façon exponentielle au fil du temps, sans aucun signe de réduction pour les années à venir. Les coûts reportés étaient principalement (i) dus aux dommages causés par les envahisseurs plutôt qu’aux dépenses engagées pour lutter contre leurs invasions, (ii) fortement biaisés vers quelques régions (Afrique australe et orientale) et secteurs d’activité (agriculture) et (iii) associés à un nombre restreint de taxons envahissants (essentiellement trois insectes ravageurs: Chilo partellus, Tuta absoluta, Spodoptera frugiperda). Notre étude met également en lumière de cruciales lacunes dans les connaissances actuelles sur les coûts économiques des invasions qui doivent encore être comblées par des efforts de recherche et des actions de gestion plus importants et étendus à travers le continent. Enfin, notre travail souligne la nécessité de l’élaboration et la mise en œuvre de mesures préventives pour empêcher l’introduction des espèces envahissantes, ainsi que l’intégration des actions de gestion aux niveaux national et régional. Compte tenu des réalités sociétales et économiques complexes des pays africains, le problème actuellement négligé des invasions biologiques devrait être une priorité pour le développement durable.

A large and increasing number of ecosystems of the planet are now invaded by alien species, resulting in detrimental impacts on biodiversity, human health, and ecosystem services (IPBES 2019). Many of these impacts can be defined and quantified as economic costs; expenditures to prevent, reduce or mitigate the losses caused by invasive alien species (IAS). Reports on the global economic costs over the last 50 years estimate that IAS are responsible for a minimum of US$1.288 trillion (2017 US dollars) in damages, a number that is steadily rising over time (Diagne et al. 2021a). Understanding and estimating economic damages caused by IAS is particularly important given that new introductions of alien species and impacts are increasing globally with no sign of slowing down (Seebens et al. 2017; Essl et al. 2020). In addition, just as current and future projections of numbers and types of IAS vary across ecosystems (van Kleunen et al. 2015; Essl et al. 2020), impacts and costs of biological invasions differ widely across space and time (Angulo et al. 2021b; Diagne et al. 2021a). Improving economic cost estimates of biological invasions across regions helps scientists, managers, and stakeholders to develop and inform benefit-cost analyses and policies for dealing with invasive alien species. Previous studies have modelled and estimated the economic costs of biological invasions for specific countries (e.g., Pimentel et al. 2005; Hoffmann and Broadhurst 2016) or globally (e.g., Diagne et al. 2021a), but a standardized assessment of costs of biological invasions with detailed information for countries and regions was lacking for most regions of the world. In this special issue on the “The Economic costs of biological invasions in the world,” 63 authors address this issue by bringing together 19 papers from 13 countries and 6 supra-national regions that report on the economic cost-dimension of biological invasions (Fig. 1, Table 1). Collectively, they provide a global, innovative perspective detailing the economic costs of biological invasions while also providing regional information to help raise public awareness, and support efficient and cost-effective decision-making Financial support to EGB was provided by the Spanish Ministry of Science (projects RED2018‐102571‐T, and PID2019-103936GB-C21) and the Government of Catalonia (ref. 2017 SGR 548)

Lionfish was studied in the mesophotic environment. 237 specimens were observed, most in the upper mesophotic zone. Males were larger than females and differences between sexes in growth models were found. Sixteen prey items were identified, the most important being the teleost families Acanthuridae and Monacanthidae, and the crustacean Penaeidae. The mean of δ13C was -17.08 ± 0.36 ‰ and δ15N was 8.68 ± 0.46 ‰, with no differences between sexes. Lionfish occupies a less extensive isotopic niche in mesophotic environment than in shallow sectors; there is an isotopic niche overlap between sexes. Likewise, lionfish has specialized trophic habits. All specimens were mature and in females regression phase predominated. In females, condition factor (CF), gonadosomatic index (GSI) and hepatosomatic index (HSI) increased with gonadal development, reaching peak in the active spawning phase, and decreasing in regression. Males had a condition factor similar to spawning females, but IGS and IHS were lower. RESUMEN En el ambiente mesofótico se observaron 237 especímenes de Pterois, mayoritariamente en la zona mesofótica superior. Los machos fueron más grandes que las hembras con modelos de crecimiento diferenciados. Se identificaron 16 ítems de presas, siendo los peces Acanthuridae y Monacanthidae y los camarones Penaeidae las más importantes. La media de δ13C fue -17,08 ± 0,36 ‰ y la de δ15N fue 8,68 ± 0,46 ‰, no detectándose diferencias entre sexos. La especie ocupa un nicho isotópico menos extenso que en sectores someros, tiene traslapo entre sexos y hábitos tróficos especialistas (Levin = 0,22). En hembras el factor de condición (FC), el índice gonadosomático (IGS) y el índice hepatosomático (IHS) aumentaron con el desarrollo gonadal alcanzando pico en fase de desove activo, y disminuyendo en regresión. Los machos tuvieron un FC similar al de hembras en desove, pero el IGS y el IHS fueron menores.

Invasive alien species pose a serious threat to the integrity and function of natural ecosystems. Understanding how these invaders alter natural communities is therefore an important aspect in predicting the likely future outcomes of biological invasions. Many studies have documented the consequences of invasive alien species on native community structure, through the displacement and local extinction of native species. However, sampling methods and intensities are rarely standardised across such studies, meaning that it is not clear whether differences in response among native communities to the same invader species are due to biological differences between the invaded regions, or differences in the methodologies used. Here we use a matched sampling methodology to compare the effects of the Argentine ant (Linepithema humile Mayr) on native ant community assemblages in two distinct biogeographical regions that share similar ecologies: Girona (Spain) and Jonkershoek Nature Reserve (South Africa). We found a strong negative association between L. humile presence and native ant species richness within both geographic regions. However, the effects differed between the two study regions: in Girona, a single native ant species (Plagiolepis pygmaea) persisted in invaded sites; by contrast, substantially more native ant species persisted at invaded sites in Jonkershoek Nature Reserve. In addition, in Jonkershoek Nature Reserve, the abundance of certain native species appeared to increase in the presence of L. humile. This study therefore demonstrates the potential variable effects of an invasive species in contrasting locations within different biogeographical regions. Future work should explore the causes of this differential resistance among communities and expand standardised sampling approaches to more invaded zones to further explore how local biotic or abiotic conditions of a region determine the nature and extent of impact of L. humile invasion on native ant communities This work was funded by grants and awards from the Natural Environmental Research Council (NERC) Case Studentship awarded to SS, JB and RN (NE/K007076/1); COST Action TD1209 (ECOST-STSM-TD1209: 070915-062123, 010715-062122, and 160614-046307); and Varley-Gradwell Travelling Fellowship

Protected areas are among the key elements of global biodiversity conservation strategies and aim to conserve native species, habitats and ecosystems. Globalisation has led to increased introductions of species outside their natural range. In their new environment, some of these non-native species have the potential to affect ecosystems and compete with or threaten native species. The environment in close proximity to protected areas is likely to be the stepping stone for non-native species to become established in protected areas. However, little is known about the role that protected area surroundings play in the permeability of protected areas to non-native species. In this thesis, I focused on protected areas and their surrounding belts to address the issue of permeability to non-native species. Examining protected areas in Norway, I showed that non-native species surrounding protected areas have a qualitative impact on the community of non-native species in protected areas. Moreover, the proportion of invasive species was higher in protected areas (40 %) compared to their belts (12 %). The number of non-native species in the surrounding areas also significantly determined the number of non-native species in protected areas. I have also highlighted the dynamics of colonization from the belts to the protected areas by showing that non-native species were detected in the protected areas on average several years after they were recorded in the belts. In addition, I showed in four European countries that the type of land use and land cover in the proximity and within protected areas plays a central role in the establishment of non-native species in protected areas. Anthropogenic land use and land cover around protected areas promoted the establishment of non-native species inside protected areas, regardless of the land use and land cover present in them. Finally, I investigated the colonization dynamics of Acacia dealbata, an invasive t ree species, in and around protected areas in central Portugal over the last twenty years. I showed that disturbances by fires and the loss of tree cover had a significant positive effect on the presence of the species. This thesis highlights the importance of the protected area surroundings for the colonization of non-native species. This is particularly relevant for future management strategies for non-native species in protected areas., Les aires protégées sont des éléments clés de la stratégie mondiale de conservation de la biodiversité, en visant à préserver les espèces, les habitats et les écosystèmes. La mondialisation a entraîné une augmentation des introductions d'espèces en dehors de leur aire de répartition naturelle. Dans leur nouvel environnement, certaines de ces espèces non indigènes ont le potentiel d’affecter les écosystèmes, de concurrencer ou de menacer les espèces locales. L'environnement à proximité des aires protégées est susceptible de servir de tremplin à ces espèces introduites avant qu’elles ne pénètrent dans les aires protégées. Cependant, on sait peu de choses sur le rôle que jouent les zones entourant les aires protégées dans cette dynamique de colonisation. Dans cette thèse, nous nous sommes concentrés sur les zones entourant les aires protégées pour aborder la question de la perméabilité des aires protégées aux espèces non indigènes. En étudiant les aires protégées en Norvège, nous avons montré que le pool d’espèces non indigènes présent autour des aires protégées a un impact qualitatif sur la communauté d'espèces non indigènes présentes dans les aires protégées, les espèces non indigènes envahissantes étant présentes dans une plus grande proportion dans les aires protégées (40 %) que dans leurs ceintures (12 %). Le nombre d'espèces non indigènes présentes autour des aires protégées détermine également le nombre d'espèces non indigènes présentes dans les aires protégées. Nous avons aussi mis en évidence la dynamique de la colonisation de l’extérieur vers l’intérieur des aires protégées en montrant que les espèces non indigènes étaient détectées dans les aires protégées plusieurs années après avoir été détectées autour d’elles. En outre, nous avons montré dans quatre pays européens que le type d’occupation du sol à proximité et au sein des aires protégées joue un rôle central dans l'établissement des espèces non indigènes dans les aires protégées. Ainsi, les habitats fortement anthropisés autour des aires protégées favorisent la présence d'espèces non indigènes dans les aires protégées, quel que soit le type d’occupation du sol dans ces dernières. Enfin, nous avons étudié la dynamique de colonisation d'Acacia dealbata, une espèce d'arbre non indigène envahissante au centre du Portugal, autour et dans cinq aires protégées, au cours de ces vingt dernières années. Nous avons montré que les perturbations par les incendies et la perte de couverture forestière favorisaient la présence de l'espèce. Cette thèse a mis en évidence l'importance des zones autour des aires protégées dans la colonisation de celles-ci par les espèces non indigènes. Ces résultats sont particulièrement pertinents pour les futures stratégies de gestion des espèces non indigènes dans les aires protégées.

Two of the world’s most invasive ants, Linepithema humile and Lasius neglectus, are destined to overlap in range as they continue to spread throughout Europe. Although L. humile arrived first, and is therefore more numerically abundant, L. neglectus is the more behaviorally dominant of the two. We performed lab trials to determine whether L. humile could use numerical abundance to overcome the behavioral dominance of L. neglectus and whether the ants’ behavioral patterns shifted when the species co-occurred. We found that L. neglectus was more aggressive when less abundant, whereas the opposite was true of L. humile. When L. neglectus was outnumbered, it employed aggressive behaviors, such as biting or chemical attacks, more frequently than L. humile; it also utilized a behavioral sequence that included mandible opening and biting. Our results for these species support the hypothesis that species modulate their behavior towards competitors, which facilitates the understanding of how multiple invasive ant species can co-occur in a given area. Moreover, our study shows that the co-occurrence of invasive species could result from the use of two strategies: (1) the Bourgeois strategy, in which aggressiveness changes based on numerical dominance and (2) the dear-enemy strategy, in which aggressiveness is reduced when competitors co-occur. Since these strategies may lead to territory partitioning, we suggest that the behavioral flexibility displayed by both species when they overlap may allow local co-occurrence and increase their likelihood of co-occurrence during their range expansion in Europe, which could have a negative cumulative impact on invaded areas.

La propagation des especes exotiques envahissantes (EEE), phenomene accelere par l’augmentation des echanges (maritimes, ferroviaires, aeriens), fait partie des risques environnementaux aux consequences parfois desastreuses sur l’economie, la biodiversite, la productivite agricole et la sante. En Republique du Benin, pays en developpement, il s’agit d’un enjeu encore meconnu et peu saisi par les pouvoirs publics. Cet article fait le point des difficultes rencontrees pour un pays comme le Benin dans la gestion des risques lies aux EEE et des differentes initiatives deja en cours.

Engager les pratiquants de loisirs dans la gestion du milieu naturel suppose d’être en capacité d’imaginer des modes de coordination adéquats, jusqu’à présent plutôt conçus par et pour les experts de la profession. Dans cet article, nous proposons de réfléchir à cette question à partir du cas des plantes aquatiques invasives, en étudiant les dispositifs mis en place sur les lacs Aquitains, dans le Sud Ouest de la France. Nous abordons ces dispositifs comme des processus de co-production territoriale, grâce à des outils d’analyse empruntés à l’économie des services. Nous montrons que les expérimentations ayant réussi à impliquer des pratiquants valorisent tout d’abord leurs compétences opérationnelles et relationnelles, et assez peu (voire pas) expertes. Ces formes d’actions collectives sont autant conditionnées par les plantes que par les supports sur lesquels celles-ci se développent. Dans ce contexte, l’implication des pratiquants de loisirs va largement contribuer à façonner la nature des actions mises en place et, par ce fait, conférer une dimension territoriale à la gestion. Ce processus s’accompagne néanmoins d’une tendance à la micro-localisation des tâches, ainsi que d’une certaine spécialisation des responsabilités, finalement assez peu compatibles avec les dynamiques spatiales des plantes, et que seuls les techniciens et les gestionnaires traditionnels de l’espace semblent en mesure de dépasser. Ces premières initiatives n’en conservent pas moins un caractère pionnier, véritable source d’inspiration pour de futures expériences de gestion participative. Involving recreational users in the management of environmental issues implies imagining new modes of cooperative actions, which have been built for professional managers. In this article, we propose to reflect on this question from the case of invasive aquatic plants on the shore lakes of Aquitaine in South Western France. We analyze these collective actions as territorial coproduction processes, relying on service economics analytical tools. We show that the collective actions that have succeeded in involving outdoor recreationists value first their operational and relational skills and rather little (if any) expertise. These actions are strongly conditioned by the type of support where the plants develop, at least as much as by the plants on which they are supposed to intervene. The involvement of recreational users will largely contribute to shaping the nature of the collective action and, as a result, add a territorial dimension. However, such a process favours the micro-localization of operations and responsibilities specialization. The latter is not adapted to the spatial dynamics of the plants. Technicians and traditional managers currently seem to be the only ones to overcome such difficulties. Neverthelss, these first initiatives are pioneering in character and a trustworthy source of inspiration for future experiments in participatory management.

Scientific and grey literature on invasive alien species (IAS) is conditioned by social, economic and political priorities, editorial preferences and species and ecosystem characteristics. This leads to knowledge gaps and mismatches between scientific research interests and management needs. We reviewed the literature on IAS management in Spain found in Scopus, Web of Science, Google Scholar and Dialnet to identify key deficiencies and priority research areas. The collected literature was classified, employing features describing formal aspects and content. We used bibliometric and keyword co-occurrence network analyses to assess the relationship between features and reveal the existence of additional topics. Most of the compiled documents (n = 388) were focused on terrestrial ecosystems and inland waters, whereas marine and urban ecosystems were under-represented. The literature was largely generic and not species-specific, focusing on raising awareness and proposing changes on current regulation as prominent approaches to prevent further introductions. The compiled authors exhibited many clear publishing preferences (e.g. language or document type), but less regarding target taxa. In addition, there was a strong association between species and the different features considered, especially between the methodological approach (e.g. review, field experiment) and the primary emphasis of study (i.e. basic/theoretical, applied or interdisciplinary). This indicates that research on IAS has had a strong species-specific focus. References about terrestrial species focused mainly on vascular plants, whereas references about inland waters were mostly on fishes and the giant reed (Arundo donax), which has been managed with partial success. Animal culling and plant removal were the most frequent eradication and small-scale control treatments, whereas the documents addressing wider spatial scales were largely theoretical. Consequently, the success of described treatments was largely uncertain. Spanish invasion science research has been occasionally innovative, incorporating novel technologies (e.g. species distribution modelling) and engaging society with citizen-science approaches. However, the ratio between basic/theoretical and applied studies indicates that more applied research/management is needed, especially in inland waters and marine ecosystems. We call for increasing effort in the effective dissemination of experience in IAS management to enhance current practical knowledge, including that of schemes undertaken by public agencies. © 2021. Rafael Muñoz-Mas et al.. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited., Spanish Ministry of Science and Innovation RED2018‐102571‐T, Spanish State Research Agency, Spanish State Research Agency, European Regional Development Fund PID2020- 118550RB, PID2019-103936GB-C21, RTI2018-093504-B-I00, Government of Catalonia 2017 SGR 548, Spanish Ministry of Science and Innovation FJCI2016-30829

Scenario analysis has emerged as a key tool to analyze complex and uncertain future socio-ecological developments. However, currently existing global scenarios (narratives of how the world may develop) have neglected biological invasions, a major threat to biodiversity and the economy. Here, we use a novel participatory process to develop a diverse set of global biological invasion scenarios spanning a wide range of plausible global futures through to 2050. We adapted the widely used “two axes” scenario analysis approach to develop four families of four scenarios each, resulting in 16 scenarios that were later clustered into four contrasting sets of futures. Our analysis highlights that socioeconomic developments and technological innovation have the potential to shape biological invasions, in addition to well-known drivers, such as climate and human land use change and global trade. Our scenarios partially align with the shared socioeconomic pathways created by the climate change research community. Several factors that drive differences in biological invasions were underrepresented in the shared socioeconomic pathways; in particular, the implementation of biosecurity policies. We argue that including factors related to public environmental awareness and technological and trade development in global scenarios and models is essential to adequately consider biological invasions in global environmental assessments and thereby obtain a more integrative picture of future social–ecological developments This research was funded through the COST Action “Alien Challenge” [Grant number TD1209]; the 2017–2018 Belmont Forum and BiodivERsA joint call for research proposals, under the BiodivScen ERA-Net COFUND programme, and with the funding organisations AEI, FWF and BMBF [grant numbers AEI PCI2018-092966 (NRP)/FWF project 4011-B32 (FE, SD, GL, BeL)/BMBF projects 01LC1807A (HS) and 01LC1807B (JMJ)]; Deutsche Forschungsgemeinschaft [grant numbers InDyNet, JE 288/8-1; JE 288/9-1, 9-2 (JMJ)/via iDiv FZT 118, 202548816 (MW)]; OP RDE grant EVA4.0 [grant number CZ.02.1.01/0.0/0.0/16_019/0000803] (AML); CONICYT [grant number AFB170008] (AP); UK-SCAPE programme, Natural Environment Research Council [grant number NE/R016429/1] (HER)

We report new localities for Callinectes sapidus in the Iberian Peninsula that widen the north-eastern limit of its distribution by more than 206 km along the Iberian Mediterranean coastline. This invasive species has been captured in the estuaries of the Fluvià, Muga and Ter rivers and has become established in the Fluvià River in only nine months since the first individual was detected. These reports show how rapid expansion of C. sapidus can be and that this may be preceded by the presence of isolated individuals We gratefully acknowledge the scientific team of the European Life project “Pletera” (LIFE13 NAT/ES/001001) and the Sorelló S.L. company for sharing their field results. This project has been financially supported by Natura Montfred company and the Aiguamolls de l’Empordà Natural Park (PNAE)

Aim: To test whether alien species with contrasting introduction pathways differ in range size, geographical distribution and their relationship with environmental variables. Location: Catalonia (NE Spain). Methods: We obtained records of 869 alien species from the Catalan alien species database at the 10-km UTM cell scale. For each species, we assigned its introduction pathways and minimum residence time (MRT). We then analysed species' range sizes in relation to their pathways and taxonomic group while accounting for MRT through linear models. We identified hotspots of alien species richness across pathways through local Gi* statistics, and we analysed their spatial congruence. We assessed the environmental drivers of alien species richness across pathways, by means of ordination methods. Results: Range size was mostly equivalent among pathways, with species that escape or spread unaided reaching smaller range size than species introduced with contaminated commodities. Among taxonomic groups, range was smaller for terrestrial invertebrates compared to plants. The spatial pattern of hotspots of alien species richness showed low congruence across pathways. Proxies that pool the effect of colonization and propagule pressure were the main drivers increasing alien species richness across pathways (except for the unaided pathway). Main conclusions: Differences among pathways can be related to a lack of human aid (unaided and contaminant pathways) and to trait selection (escape and contaminant pathways), while differences among taxonomic groups (terrestrial invertebrates and plants) may be related to dispersal capacity. The remaining pathways and taxonomic groups were similar in range size, suggesting shared underlying factors. Invasion risk from different human socio-economic activities is spread over our study area rather than concentrated in unique high-risk areas This can be the foundation for a prevention scheme that monitors areas susceptible to invasion for the different pathways.

Mate recognition is the process of identifying and assessing the appropriate species, sex or population of another individual for their suitability as a potential mate. Recognition may be innate or learned. Learning, the acquisition of knowledge or skills through experience, involves a relatively long-term change in behavioral responses. In this study we examined learned and innate mate recognition in invasive male mosquitofish, Gambusia holbrooki, interacting with female conspecifics and male and female native toothcarp, Aphanius iberus. Male mosquitofish directed no mating attempts at male toothcarp whereas numerous attempts were made toward female toothcarp. Male mosquitofish therefore differentiated between males and females, but initially did not distinguish between con- and heterospecific females. Neither the presence of a male toothcarp, nor the presence of a refugia affected the number of mating attempts received by females. However, by the second day males appeared to learn to more accurately direct their mating attempts, with larger female mosquitofish receiving the most attention, though smaller toothcarp females were still harassed. We propose that male mosquitofish, with a coercive mating system, are selected for persistence despite rejection by potential mates. In this scenario, the pool of potential mates may include heterospecifics whose avoidance of mating attempts may be ignored by male mosquitofish. It may thus be adaptive for male mosquitofish to prioritize sex recognition over species recognition: if one sex is recognized as a “non-mate” this will cut 50% from the pool of potential mates whereas recognition of a single species will remove many fewer potential mates from the pool. This innate sex recognition together with rapid learning of species identity may be a factor in the invasive success of mosquitofish This research was supported by a Marie Curie International Reintegration Grant within the 7th European Community Framework Program (KM). Additional financial support was provided by the Spanish Ministry of Science (projects CGL2009-12877-C02-01, CSD2009-00065, and PID2019-103936GB-C21).