Marine Invasive Species Research Articles

Microbiota dynamics in lionfish (Pterois): insights into invasion and establishment in the Mediterranean Sea.

Lionfishes (Pterois spp.), originally native to the Indo-Pacific and Red Sea, have become one of the most invasive marine species globally, including the recent establishment in the Mediterranean Sea. This study investigates the microbiota of lionfish to explore its potential role in their invasion success and establishment. Using high-throughput sequencing and microbiota analyses, we characterized the species-specific core microbiome and identified habitat-specific markers across different regions (Red Sea, Mediterranean Sea, Caribbean, and aquarium populations) and organs. Focusing on the Mediterranean invasion, we tracked lionfish distribution and population dynamics along the Israeli coastline from 2017 to 2023, monitoring size, seasonal trends, and depth preferences. Our findings reveal that lionfish initially established themselves in deeper waters before expanding to shallower habitats, with a gradual increase in population size and body length over time. From a microbial aspect, we compared the microbiota of lionfish organs and identified a similar pattern (Photobacterium), to Earlier Lessepsian migrants fish species. This study provides novel insights into the interactions between microbiota and host ecology, shedding light on the mechanisms that may support the successful invasion. This study contributes to the understanding of lionfish invasion dynamics in the Mediterranean. It highlights the microbiota as an integral component for studying the ecological and biological mechanisms underpinning invasive species' success and establishment of lionfish.

Morphological and genetic evidence supports that invasive Carcinus Leach, 1814 in South Australia are C. maenas (Linnaeus, 1758)

ABSTRACT Accurate identification of invasive marine species is essential for understanding species range expansions and developing taxon-specific surveillance tools. The globally invasive European green crab Carcinus maenas, and the Mediterranean green crab C. aestuarii, which has a more limited introduced range and is a lesser concern as a pest, can be difficult to distinguish morphologically and can also hybridise. Although the species are visually similar, it has been proposed that they can be distinguished using carapace morphometrics. In temperate South Australia, invasive Carcinus have been reported as C. maenas. This study aimed to confirm the identity of invasive Carcinus in South Australia using carapace morphometrics and mtDNA COI gene sequencing. Carapace width:length ratios of 1,311 Carcinus from South Australia were variable within sexes and corresponded to those of both C. maenas and C. aestuarii. However, COI sequencing of 59 of these crabs revealed ~ 100% sequence matches to C. maenas and diverged from C. aestuarii sequences on GenBank by an average of 11.5%. Results supported that the South Australian population is C. maenas and that intraspecific morphological variation prevents carapace ratios alone from distinguishing species of Carcinus. DNA sequencing should be used to confirm the species identity of crabs identified as Carcinus during new incursions.

The transition from resistance to acceptance: Managing a marine invasive species in a changing world

Abstract Marine invasive species can transform coastal ecosystems, yet mitigating their effects can be difficult, and even impractical. Often, marine invasive species are managed at poorly matched spatial scales, and at the same time, rates of spread and establishment are increasing under climate change and can outpace resources available for population suppression. These circumstances challenge traditional conservation goals of maintaining a historic environmental state, especially for a species like the European green crab (Carcinus maenas), a formidable invader with few examples of successful long‐term removal programs. A management paradigm where decision alternatives include resisting or accepting a new ecological trajectory may be needed. We apply mathematical concepts from decision theory to develop a quantitative framework for navigating management decisions in this new resist‐accept paradigm. We develop a model of European green crab growth, removal and colonization, and we find optimal levels of removal effort that minimize both ecological change and removal cost. We establish a benchmark of colonization pressure at which green crab density becomes decoupled from a decision maker's actions, such that population control can no longer shape the invasion trajectory. For informing the decision boundary between resistance and acceptance, our results highlight that a decision maker's understanding of how removal cost scales with removal effort is more important than understanding the density‐impact relationship. We show that assuming stationary system dynamics can result in sub‐optimal levels of species removal effort, highlighting the importance of developing anticipatory management strategies by accounting for non‐stationary dynamics. Policy implications. For marine invasive species that can disperse across long distances and recolonize rapidly after removal, the focus of conservation policy should shift away from understanding how to resist change to understanding when to stop resisting change. Navigating this decision problem involves trade‐offs among competing objectives, highlighting the need for structured approaches to elicit objective weights that reflect the values of the decision maker. For natural resource managers facing possible ecosystem transformation, this decision framework can enable proactive and strategic decisions made under uncertainty in a changing world.

Marine Invasive Algae's Bioactive Ingredients as a Sustainable Pathway in Cosmetics: The Azores Islands as a Case Study.

Marine invasive species pose significant ecological, economic, and social challenges, disrupting native ecosystems, outcompeting local species and altering biodiversity. The spread of these species is largely driven by global trade, shipping, and climate change, which allow non-native species to establish themselves in new environments. Current management strategies, including early detection, rapid response, and biosecurity measures, have had some success, but the complexity and scale of the problem require continuous monitoring. This review explores the possibility of using some marine invasive species as skincare ingredients and explores the Azorean islands as a case study for the valorization of biomass. Additionally, this review addresses legislative barriers that delay the development of sustainable cosmetic markets from invasive species, highlighting the regulatory landscape as a critical area. It concludes that marine invasive species present a regional and global problem that requires regional and global solutions. Such solutions strongly need to address environmental impacts and net socioeconomic benefits, but such solutions must also consider all regional differences, technical capacities and financial resources available. Thus, as a future perspective, strategies should emphasize the need for international collaboration and the development of more effective policies to prevent the spread of invasive species. There is still much work to be completed. By working together, the biodiversity for future generations will be better monitored and explored.

Inventory of Shallow-Water Fouling Invertebrates of Long Island, New York

Invasive marine invertebrates are increasingly recognized as a potential disturbance to coastal ecosystems. We sought to better document the taxonomic composition of subtidal communities around Long Island to obtain a baseline that can be used to monitor current and future invasions of non-indigenous species. We placed settlement blocks at 18 sites along the coast of Long Island, New York, for three months. After recovering blocks at 12 sites, we analyzed the taxonomic composition of fouling communities on the blocks. We observed 64 invertebrate and 3 algal taxa, with large variation in taxon richness among sites. Multivariate analyses revealed that although taxon composition was significantly dissimilar between north and south shores, variation in dissimilarity did not differ significantly between shores. The high variability in taxon composition observed among sites indicates that additional research is needed to expand our knowledge of invertebrate diversity in the waters surrounding Long Island. Adding more sites and replicate blocks within sites could improve future sampling designs. This research will benefit continuing efforts to monitor, manage, and prevent the establishment of marine invasive species.

Investigating Consumer Attitudes and Market Trading of Edible Marine Invasive Alien Species in the Greek Seafood Market

Marine invasive alien species (IAS) are spreading in the Mediterranean Sea, altering species composition and reshaping marine ecosystems. The study explores consumer attitudes towards the consumption of marine invasive alien species (IAS), particularly lionfish and Atlantic blue crab, in the Greek seafood market. These species are considered a threat to marine biodiversity but are also being considered for commercial seafood to mitigate their ecological impact. Through surveys of consumers and seafood retailers, the research finds that while Greek consumers show a positive attitude towards consuming these species, they often lack awareness of their ecological impact. Retailers see potential in promoting these invasive species, with freshness, hygiene, and poison concerns being the most important factors for consumers when purchasing seafood. In general, there is a need for better public education regarding the ecological and health impacts of IAS consumption. Factors that could increase consumption include recommendations from seafood retailers, promotion by TV cooking shows, and quality certifications. The study suggests that aligning consumer education with conservation goals could help control the spread of IAS while supporting local fisheries.

Research horizons for invasive marine species detection with eDNA/eRNA

The global marine ecosystem is changing rapidly as the result of biogeochemical cycles and ecosystem structure being altered by industrial civilization. Invasive marine species (IMS) are one of the most damaging regional consequences of human activity, and one of the most easily attributable to specific processes. This makes IMS introduction one of most tractable threats for management by appropriate policies. Once established, a different set of policies are required either to restrict IMS spread, or to attempt local eradication. The key ecosystem management tool for IMS damage mitigation is rapid, widely deployable IMS detection. Environmental Nucleic Acids (eNA), combining environmental DNA (eDNA) and environmental RNA (eRNA) analyses, have emerged as valuable tools for sensitive, cost-effective and readily deployable detection of IMS. Methods for IMS detection by eNA are still being developed through a widespread and active research community, so identifying the limitations of current processes will help prioritise eNA-based IMS detection research. We analysed and synthesised the opinions of expert marine ecosystem managers and researchers in Australia and New Zealand about the knowledge gaps and research needs for eNA-based IMS detection. This synthesis was placed in context with current research literature on what eNA technologies are currently providing as an IMS management tool; what problems exist with the current technology; and what could be done to improve this general approach. Our analyses produced a list of priorities that chart a path towards the best possible systems for IMS detection by eNA.

Electric underwater tools for sun coral management

Sun coral, identified as Tubastraea coccinea and Tubastraea tagusensis, are invasive marine species originally from the Pacific Ocean that have become a significant threat to native biodiversity and ecosystems in Brazil. The rapid growth and unique reproduction strategies of Tubastraea species have facilitated their success as invasive species. In the past two decades, Brazil has experienced a notable loss of biodiversity, partially attributed to invasive species, as reported by the Brazilian Platform on Biodiversity and Ecosystem Services. Current management efforts primarily involve manual removal, often employing sledgehammers and chisels, carried out by environmental government agencies, in partnership with NGOs and volunteers. However, the need for more efficient management strategies emphasizes the important role of engineering and technology in improving environmental management. To address this issue, our work focuses on the development and prototyping of two underwater tools: an impact hammer and a rotating brush. These tools are designed with ergonomic features, operating time, and size considerations suitable for use by SCUBA divers. Our prototypes have successfully met the required specifications and offer potential for large-scale manufacturing, promising more effective measures for controlling invasive sun coral in Brazil.

The Mediterranean Mussel Mytilus galloprovincialis (Mollusca: Bivalvia) in Chile: Distribution and Genetic Structure of a Recently Introduced Invasive Marine Species.

The genetic characteristics of invasive species have a significant impact on their ability to establish and spread. The blue mussel (Mytilus galloprovincialis), native to the Mediterranean Sea, is a leading invasive species of intertidal coasts throughout much of the world. Here, we used mitochondrial DNA sequence data to investigate the genetic diversity and phylogeographic structure of invasive (M. galloprovincialis) versus native (Mytilus chilensis) populations of blue mussels in Chile. We evaluated whether genetic diversity in invasive populations could be explained by the genetic characteristics of the native sources from which they might be derived. A phylogenetic analysis confirmed two lineages of the invasive M. galloprovincialis, i.e., the NW Atlantic and the Mediterranean lineages. We found no evidence of genetic structure in the invasive range of M. galloprovincialis in Chile, most probably because of its recent arrival. We did, however, detect a spatial mixture of both M. galloprovincialis lineages at sampling locations along the Chilean coast, giving rise to higher levels of genetic diversity in some areas compared to the population of native M. chilensis. The coastal area of the invasion is still small in extent (~100 km on either side of two large ports), which supports the hypothesis of a recent introduction. Further expansion of the distribution range of M. galloprovincialis may be limited to the north by increasing water temperatures and to the south by a natural biogeographic break that may slow or perhaps stop its spread. The use of internal borders as a tool to minimise or prevent M. galloprovincialis spread is therefore a genuine management option in Chile but needs to be implemented rapidly.

Another One Bites the Net: Assessing the Economic Impacts of Lagocephalus sceleratus on Small-Scale Fisheries in Greece

The assessment of the economic impacts of marine invasive species is fundamental for adopting mitigation measures, yet such impacts have been underreported in the Mediterranean Sea. The silver-cheeked toadfish (Lagocephalus sceleratus) is a toxic pufferfish that since its introduction has seriously disturbed small-scale fisheries along the eastern Mediterranean coast. This species depredates on fishing gears, causing damage to nets, longlines and commercial catches. To quantify its economic impact on small-scale fisheries, we interviewed 141 fishers from Crete (Cretan and Libyan Sea) and the Ionian Sea (Greece) during May 2020–December 2022. The mean annual economic cost resulting from L. sceleratus depredation was estimated at EUR 6315 ± 2620 per vessel in Crete and EUR 258 ± 120 in the Ionian Sea. Additionally, observer surveys carried out on board small-scale fishing vessels in Crete showed that depredation probability was significantly influenced by fishing depth, sea surface temperature, gear type (nets, longlines) and region (Cretan, Libyan Sea). L. sceleratus was caught more frequently and in higher numbers in the Libyan Sea. In response to depredation, fishers in Crete have altered their fishing tactics in terms of fishing in deeper waters, reducing fishing time and changing the technical characteristics of fishing gears. Our results underscore the adverse impacts of L. sceleratus on Greek small-scale fishers, emphasizing the need for region-specific management plans where the species establishes large populations.

Environmental DNA–RNA dynamics provide insights for effective monitoring of marine invasive species

AbstractEnvironmental DNA and RNA (eDNA/eRNA) can serve as molecular tools for biodiversity monitoring and biosecurity surveillance. However, uncertainties still exist regarding the persistence and dynamics of marine nucleic acids in the environment and the effects of post‐sampling storage on species detectability. To bridge these gaps, an experiment was conducted in an Auckland marina, a known New Zealand entry point for marine non‐indigenous species (NIS). We targeted a prominent invader, the Mediterranean fanworm Sabella spallanzanii, for eDNA/eRNA‐based detection. Permeable dialysis bags filled with seawater collected near an S. spallanzanii colony were deployed in the marina to simulate environmental conditions, with a subset of bags stored on ice to mimic field storage conditions. Sabella spallanzanii eDNA/eRNA signal was quantified using droplet digital PCR on samples collected over 24 h of dialysis bag deployment. Results challenged traditional first‐order decay models, showing inconsistent eDNA/eRNA signal patterns and no significant concentration changes between 0 and 24 h. Consequently, total eDNA fragmentation was assessed using the Agilent 2100 Bioanalyzer® electrophoresis system, which revealed a rise in the number of total eDNA fragments and an unexpected increase in the median fragment size of total eDNA under field conditions over time, likely originating from the ambient microbiome. Additional analysis using long‐read sequencing (Oxford Nanopore Technologies, UK) revealed an increase in microbial eDNA reads within the in‐field samples, suggesting potential microbial growth within the dialysis bags. In contrast, the ice‐stored samples exhibited no significant changes in the number of reads assigned to microbial taxa, implying limited microbial growth in cold storage. These findings provide insights into total eDNA dynamics and its potential impact on targeted eDNA concentration and detection. Further comprehensive research on eDNA/eRNA dynamics, particularly focused on eRNA, is essential, as this understanding is crucial for refining survey interpretation and sampling design for effective environmental management.

Species range shifts, biological invasions and ocean warming

Marine species are moving beyond their native geographical ranges in response to climate change and shifts in other abiotic conditions, establishing populations at higher latitudes. At the same time, species are introduced into new marine regions as a consequence of an increasingly connected world. The success of such range expansions, whether from shifts associated with climate change or human-mediated introductions, depends on the biotic interactions and environmental conditions at the recipient site and/or the capacity of species to adapt to these new conditions. Originating from a special session held at the Association for the Sciences of Limnology and Oceanography (ASLO) Aquatic Sciences Meeting 2021, the present Theme Section (TS) brings together the current research on 2 interrelated marine ecological topics: (1) invasive species in a warming ocean, and (2) climate-mediated species range shifts. Our investigation of the temporal trends in publications highlights that only one-tenth of studies on marine invasive species examine the species’ interaction with ocean warming. The topic of range shifting species receives slightly more attention than climate driven invasions, but both exhibited a comparable, similarly fast-growing publication rate. Overall, the papers in this TS provide evidence that global warming, and occasionally environmental degradation, are crucial factors altering the distribution of both marine invasive species and range-shifting species. Even though the published literature and even the contributions to this TS only infrequently focus on the interaction between these 2 topics, we propose that future collaboration between scientists from both fields would advance our understanding of the impact of global warming on the shifting distributions of native and invasive species and would allow the development of conservation and management plans in a warming ocean.

Creating New Antifoulants Using the Tools and Tactics of Medicinal Chemistry.

The unwanted accumulation of marine micro- and macroorganisms such as algae and barnacles on submerged man-made structures and vessel hulls is a major challenge for any marine operation. Known as biofouling, this problem leads to reduced hydrodynamic efficiency, significantly increased fuel usage, microbially induced corrosion, and, if not managed appropriately, eventual loss of both performance and structural integrity. Ship hull biofouling in the international maritime transport network conservatively accounts for 0.6% of global carbon emissions, highlighting the global scale and the importance of this problem. Improved antifouling strategies to limit surface colonization are paramount for essential activities such as shipping, aquaculture, desalination, and the marine renewable energy sector, representing both a multibillion dollar cost and a substantial practical challenge. From an ecological perspective, biofouling is a primary contributor to the global spread of invasive marine species, which has extensive implications for the marine environment.Historically, heavy metal-based toxic biocides have been used to control biofouling. However, their unwanted collateral ecological damage on nontarget species and bioaccumulation has led to recent global bans. With expanding human activities within aquaculture and offshore energy, it is both urgent and apparent that environmentally friendly surface protection remains key for maintaining the function of both moving and stationary marine structures. Biofouling communities are typically a highly complex network of both micro- and macroorganisms, representing a broad section of life from bacteria to macrophytes and animals. Given this diversity, it is unrealistic to expect that a single antifouling "silver bullet" will prevent colonization with the exception of generally toxic biocides. For that reason, modern and future antifouling solutions are anticipated to rely on novel coating technologies and "combination therapies" where mixtures of narrow-spectrum bioactive components are used to provide coverage across fouling species. In contrast to the existing cohort of outdated, toxic antifouling strategies, such as copper- and tributyltin-releasing paints, modern drug discovery techniques are increasingly being employed for the rational design of effective yet safe alternatives. The challenge for a medicinal chemistry approach is to effectively account for the large taxonomic diversity among fouling organisms combined with a lack of well-defined conserved molecular targets within most taxa.The current Account summarizes our work employing the tools of modern medicinal chemistry to discover, modify, and develop optimized and scalable antifouling solutions based on naturally occurring antifouling and repelling compounds from both marine and terrestrial sources. Inspiration for rational design comes from targeted studies on allelopathic natural products, natural repelling peptides, and secondary metabolites from sessile marine organisms with clean exteriors, which has yielded several efficient and promising antifouling leads.

Long-Term Population Genetic Features of the Rhopilema nomadica Jellyfish from the Israeli Mediterranean Coasts

The rhizostomatid scyphozoan Rhopilema nomadica is one of the most notorious marine invasive species established in the eastern Mediterranean Sea. Using seven microsatellite loci, here, we examined the population genetic structures on 587 individual tissue samples collected from 21 sites along the Mediterranean coast of Israel over a period of 16 years. The results indicate unique microsatellite landscapes for all samples, which belong to a single unstructured population. The >20 alleles found in most loci, low fixation index (F) values (average 0.106), and high heterozygosity (average 0.667) suggest random or assortative mating. Additionally, the low overall differentiation (Fst) values (0.043) and pairwise Fst values between the samples collected in different years indicated gene flow and random mating over the years, potentially due to the long-lasting podocytes, scyphistomae, and adults causing a population overlap between the sampled months/years. Likewise, analyses were conducted between seasons, sites, and early/intermediate/late periods of collecting years. These results support the previous analyses performed on the mitochondrial gene cytochrome oxidase subunit I (COI) sequences, altogether indicating a highly polymorphic single unstructured R. nomadica population in the Levant, possibly backed by independent introductions. The results hint to the existence of highly functional connectivity with a genetically highly diverse source population.

Can we control marine invasive alien species by eating them? The case of Callinectes sapidus

Can we control marine invasive alien species by eating them? The case of Callinectes sapidus

Invasive European green crab (Carcinus maenas) predation in a Washington State estuary revealed with DNA metabarcoding.

Predation by invasive species can threaten local ecosystems and economies. The European green crab (Carcinus maenas), one of the most widespread marine invasive species, is an effective predator associated with clam and crab population declines outside of its native range. In the U.S. Pacific Northwest, green crab has recently increased in abundance and expanded its distribution, generating concern for estuarine ecosystems and associated aquaculture production. However, regionally-specific information on the trophic impacts of invasive green crab is very limited. We compared the stomach contents of green crabs collected on clam aquaculture beds versus intertidal sloughs in Willapa Bay, Washington, to provide the first in-depth description of European green crab diet at a particularly crucial time for regional management. We first identified putative prey items using DNA metabarcoding of stomach content samples. We compared diet composition across sites using prey presence/absence and an index of species-specific relative abundance. For eight prey species, we also calibrated metabarcoding data to quantitatively compare DNA abundance between prey taxa, and to describe an 'average' green crab diet at an intertidal slough versus a clam aquaculture bed. From the stomach contents of 61 green crabs, we identified 54 unique taxa belonging to nine phyla. The stomach contents of crabs collected from clam aquaculture beds were significantly different from the stomach contents of crabs collected at intertidal sloughs. Across all sites, arthropods were the most frequently detected prey, with the native hairy shore crab (Hemigrapsus oregonensis) the single most common prey item. Of the eight species calibrated with a quantitative model, two ecologically-important native species-the sand shrimp (Crangon franciscorum) and the Pacific staghorn sculpin (Leptocottus armatus)-had the highest average DNA abundance when detected in a stomach content sample. In addition to providing timely information on green crab diet, our research demonstrates the novel application of a recently developed model for more quantitative DNA metabarcoding. This represents another step in the ongoing evolution of DNA-based diet analysis towards producing the quantitative data necessary for modeling invasive species impacts.

TEMPERATURE AND SALINITY AFFECT DEVELOPMENT OF THE PARASITIC SEA ANEMONE EDWARDSIELLA LINEATA POTENTIALLY LIMITING ITS IMPACT AS A BIOLOGICAL CONTROL ON THE CTENOPHORE MNEMIOPSIS LEIDYI.

The lined sea anemone, Edwardsiella lineata, parasitizes the ctenophore Mnemiopsis leidyi, which is one of the most destructive marine invasive species in the world. Mnemiopsis leidyi is known to tolerate a wide range of environmental conditions. However, the environmental tolerances of its most prominent parasite have never been characterized. Here we determined the effects of temperature (18, 22, 26, and 30 C) and salinity (6, 15, 24, and 33 ppt) on the survival and development of E. lineata from a vermiform parasite to a free-living polyp. At higher temperatures and lower salinities, E. lineata experienced significantly higher mortality, and it failed to develop into an adult polyp at the highest temperature (30 C) and lowest salinities we tested (6 ppt or 15 ppt). While such temperature and salinity restrictions would not currently prevent E. lineata from infecting M. leidyi in many of the European waters where it has become a destructive invasive species, these environmental limitations may be reducing overlap between host and parasite within the host's native range, a situation that could be exacerbated by climate change.

Hybridization and adaptive introgression in a marine invasive species in native habitats

Hybridization and adaptive introgression in a marine invasive species in native habitats

Horizon scanning of potential threats to high-Arctic biodiversity, human health and the economy from marine invasive alien species: A Svalbard case study.

The high Arctic is considered a pristine environment compared with many other regions in the northern hemisphere. It is becoming increasingly vulnerable to invasion by invasive alien species (IAS), however, as climate change leads to rapid loss of sea ice, changes in ocean temperature and salinity, and enhanced human activities. These changes are likely to increase the incidence of arrival and the potential for establishment of IAS in the region. To predict the impact of IAS, a group of experts in taxonomy, invasion biology and Arctic ecology carried out a horizon scanning exercise using the Svalbard archipelago as a case study, to identify the species that present the highest risk to biodiversity, human health and the economy within the next 10 years. A total of 114 species, currently absent from Svalbard, recorded once and/or identified only from environmental DNA samples, were initially identified as relevant for review. Seven species were found to present a high invasion risk and to potentially cause a significant negative impact on biodiversity and five species had the potential to have an economic impact on Svalbard. Decapod crabs, ascidians and barnacles dominated the list of highest risk marine IAS. Potential pathways of invasion were also researched, the most common were found associated with vessel traffic. We recommend (i) use of this approach as a key tool within the application of biosecurity measures in the wider high Arctic, (ii) the addition of this tool to early warning systems for strengthening existing surveillance measures; and (iii) that this approach is used to identify high-risk terrestrial and freshwater IAS to understand the overall threat facing the high Arctic. Without the application of biosecurity measures, including horizon scanning, there is a greater risk that marine IAS invasions will increase, leading to unforeseen changes in the environment and economy of the high Arctic.

MarINvaders: A web toolkit of marine species for use in environmental assessments

AbstractInvasive species are the second most important reason for species extinction since 1500 ad. In addition, these invasive species can cause vast economic loss. In marine ecoregions, alien species introductions are increasing, and those that become invasive have caused profound changes in many marine ecoregions. We compiled a database consisting of information about where species are alien, where they are not, and which species are listed as threatened by invasive species. In addition, we developed an interactive Webapp for visualizing and analyzing the results. We used the Ocean Biogeographic Information System (OBIS) for identifying the presence of a species in a marine ecoregion. Information from the World Register of Marine Species (WoRMS), the Global Invasive Species Database (GISD), and the Nature Conservancy database on marine invasive species (NatCon) was used to identify the names and locations of marine alien species. Information from the International Union for Conservation of Nature (IUCN) Red List revealed which species are considered to be threatened by invasive species. Our database lists 112,399 marine species, of which 966 are alien species and 1655 are listed as threatened by invasive species by the IUCN. These are distributed throughout 225 marine ecoregions (97% of marine ecoregions). Our results confirm previous studies about the prevalence of alien and invasive species and provide an up‐to‐date status about known and recorded species and their distribution. This information can be used as a fundament for developing impact assessment models and identifying management strategies to combat marine invasive species.