Impact Of Non-indigenous Species Research Articles

Harnessing environmental DNA to reveal biogeographical patterns of non-indigenous species for improved co-governance of the marine environment in Aotearoa New Zealand

Aotearoa New Zealand’s Northern region is a major gateway for the incursion and establishment of non-indigenous species (NIS) populations due to high numbers of recreational and commercial vessels. This region also holds a unique marine ecosystem, home to many taonga (treasured) species of cultural and economic importance. Regular surveillance, eradication plans and public information sharing are undertaken by local communities and governmental organizations to protect these ecosystems from the impact of NIS. Recently, considerable investments went into environmental DNA (eDNA) research, a promising approach for the early detection of NIS for complementing existing biosecurity systems. We applied eDNA metabarcoding for elucidating bioregional patterns of NIS distributions across a gradient from harbors (NIS hotspots) to open seas (spreading areas). Samples were collected during a research cruise sailing across three Aotearoa New Zealand harbors, Waitematā, Whangārei and Pēwhairangi (Bay of Islands), and their adjacent coastal waters. The small-ribosomal subunit (18S rRNA) and mitochondrial cytochrome c oxidase I (COI) genes were screened using the online Pest Alert Tool for automated detection of putative NIS sequences. Using a probabilistic modelling approach, location-dependent occupancies of NIS were investigated and related to the current information on species distribution from biosecurity surveillance programs. This study was collaboratively designed with Māori partners to initiate a model of co-governance within the existing science system.

Reviewing Introduction Histories, Pathways, Invasiveness, and Impact of Non-Indigenous Species in Danish Marine Waters

Non-indigenous species (NIS) are of concern for biodiversity conservation and ecosystem functioning. We present an updated list of NIS, including cryptogenic species, from Danish marine waters containing 123 species. Benthic invertebrates (36%) and phytoplankton (28%) dominate the list, but fish (15%) and macroalgae (13%) are also important. The Limfjord in Northern Jutland emerges as a hotspot for the introduction of NIS. Data from multiple sources were included, i.e., the National Monitoring Program (NOVANA), the National Fish Atlas project, the citizen science project Arter.dk, research articles, and annual national reports of the ICES working group ITMO. Forty-six NIS species were subject to expert judging using a modified Harmonia protocol; 19 were found to fulfil the four selected criteria identifying a species as being ‘invasive’. Additionally, 38 species, not yet recorded in Danish waters, were evaluated using the same method, and 31 were found to fulfil the ‘invasive’ criteria. For nine selected species, introduction history, distribution maps, and time-series diagrams are presented. Our data document that the national monitoring efforts should be expanded to record macrozooplankton, coastal fish, and mobile epibenthic species. Furthermore, the national data repository, Arter.dk, should be expanded to enable more detailed documentation of new NIS records.

Measures and Gap Analysis on the Impact of Non-Indigenous Species on the Black Sea Ecosystem

Measures and Gap Analysis on the Impact of Non-Indigenous Species on the Black Sea Ecosystem

Non-indigenous Species in the Mediterranean Sea: Turning From Pest to Source by Developing the 8Rs Model, a New Paradigm in Pollution Mitigation

For mitigation of the effects of pollution, the media, policy makers and, in turn, the scientific community and industry each provide contributions through development of a sense of urgency, and with guidelines and solutions. For non-indigenous species (NIS) that can frequently have negative impacts on the native biota, this is often conveyed in an emotive way to the general public, who are typically keen to help and to get personally involved. This might be through organization of cleaning campaigns, influence on the media, or collaboration with scientists, to inform them of the local presence and abundance of NIS. Alternatively, they might proactively develop technological solutions themselves. To assess the current state of affairs, we reviewed the presence and effects of NIS in the Mediterranean Sea. As so often, any well-planned and successful activity is directly linked to financing, or a lack thereof, and this leads to sometimes untargeted and sporadic measures that are developed within a project or over a limited timeframe, without any sustainability measures. Therefore, we also assessed the activities and strategies that have been financed in this area of NIS mitigation. Based on this review of the presence and impact of NIS, and previous and ongoing activities, we propose a new paradigm to mitigate such pollution: the 8Rs model (i.e., Recognize, Reduce, Replace, Reuse, Recycle, Recover/ Restore, Remove, Regulate). This model extends from the more traditional 3Rs model (i.e., Reduce, Reuse, Recycle) that is often used and promoted for innovative waste management strategies. Importantly, the 8Rs model can be applied sequentially, for either prevention of NIS introduction, or preparation of mitigation measures. The 8Rs model was constructed based on Mediterranean NIS, although we believe it can be applied to other sources of pollution and other geographic areas. Importantly, the 8Rs model represents a general framework to organize and categorize future pollution mitigation strategies. This approach is essential for development of any action plan to influence the administrative and financial decision makers who essentially enable these activities, and therefore who have important roles in the guarantee of sustainability of these actions, and the creation of innovative societies.

Invasive biota in the deep-sea Mediterranean: an emerging issue in marine conservation and management

Although the ecological importance and impact of non-indigenous species is increasingly recognised and documented in shallow water ecosystems, their presence beyond the shelf has scarcely been documented. A survey of the upper slope biota of the Mediterranean coast of Israel revealed the presence at 200-m depth of individuals of three Erythraean species, the crocodile toothfish Champsodon nudivittis, Golani’s round herring Etrumeus golanii, and the burrowing goby, Trypauchen vagina. In the past decade several Erythraean species, some newly arrived, some well-established, have been collected on the Levantine lower shelf and upper slope. The species invasion revealed that thermal niche estimations based on the species’ native environment may have underestimated their ability to tolerate lower temperatures. The results reported here suggest that the wide thermal tolerance of some Erythraean species may facilitate their bathymetric and geographic expansion. Their spread to the depths where the unique, diverse and fragile mesophotic ‘animal forests’ occur, bodes ill to these beleaguered communities.

Marine Biodiversity - Warming vs. Biological Invasions and overfishing in the Mediterranean Sea: Take care, ‘One Train can hide another’

Biodiversity means the variety of life, encompassing levels of complexity from within species to across ecosystems. Biodiversity therefore includes several dimensions: evolutionary scale (genetic, species, higher taxonomic levels and phylogenetic diversity), functional scale, organizational scale (patch, ecosystem, landscape/seascape diversity), spatial scale (from sample to local, regional and global richness) and heterogeneity diversity. Biodiversity can therefore be measured in different and complementary ways, thus involving the use of at least 200 different metrics, which can suggest different and contrasting conclusions. It is worth emphasizing that species richness may be the least appropriate metric, despite its popular acceptance. There is a growing tendency for stakeholders, managers, government officials, environmentalists, scientists, politicians and the media to focus, as concerns threats to biodiversity, on species richness and climate change. However, focusing on climate warming can mask other stressors that, today, and perhaps for decades to come, may have more impact on ecosystems than global warming. In the Mediterranean Sea, the overall impact of Non-Indigenous Species (NISs) and overfishing on species diversity, ecosystem diversity and ecosystem functioning exceeds to a greater or lesser degree the direct impact of warming. Drastically altered functioning patterns, and even new ecosystems are spreading throughout the Mediterranean Sea. This trend is likely to become more pronounced over the next decades. Ecosystem goods and services are also being profoundly altered, generally towards a decline, as illustrated by the overgrazed barren grounds of the eastern basin, which no longer support fisheries, by the impact of the Caulerpa meadows on the scuba diving business and the economic value of the fisheries of the western basin, by the brackish lagoon ecosystems and by the blooms of the introduced comb jelly Mnemiopsis leidyi in the Black Sea, before the arrival of its predator Beroe ovata. Here, we draw attention to the fact that, at this moment and probably also in the future, the huge flow of NISs and overfishing constitute worrying issues, although largely ignored by stakeholders and political authorities. Take care: Un train peut en cacher un autre (one train can hide another; i.e. one danger may hide other unsuspected dangers), that is to say the impact of warming may contribute to hiding other effects, of at least equal gravity, such as biological invasions and overfishing.

Invading the natural marine substrates: a case study with invertebrates in South Brazil

The number of biological invasions has grown dramatically in recent decades, as well as the world's human population and coastal development. Anthropogenic habitats, such as pier pilings and break waters, have been constantly added to marine environment, usually concentrated in estuarine areas. These habitats are focal points for marine invasions, but relatively little is known about the spread of non-indigenous species (NIS) to nearby natural habitats. This study aimed to determine the extent to which NIS have spread to natural substrates both inside estuarine areas and in the adjacent open sea. We conducted a field survey and a literature review, which have been critically discussed and validated. The updated NIS list of benthic invertebrates comprises 19 species: Ascidiacea (5), Cirripedia (5), Cnidaria (3), Mollusca (3), Polychaeta (1), Decapoda (1), and Echinodermata (1). Our results suggested substantial spread of non-indigenous species into natural substrates. Altogether, 18 and 16 NIS were recorded in artificial and natural substrata, both representing 13% of the total species in each habitat. The percentage of NIS was more pronounced in the estuarine areas, 17.6% in artificial habitats and 18.6% in natural ones. Programs developed for the monitoring of marine invasion have to broaden their focus including natural areas adjacent to ports and marinas, to follow the spread and impact of NIS on these areas.

Endemism Predicts Intrinsic Vulnerability to Nonindigenous Species on Islands

While numerous efforts have been made to identify and quantify factors controlling invasibility of biological communities, less attention has been given to analyzing the expressions of vulnerability to nonindigenous species (NIS). Using the International Union for the Conservation of Nature and Natural Resources Red List database for birds, mammals, and amphibians and the Invasive Species Specialist Group global invasive species database as sources of information, we developed a new indicator for the relative intrinsic vulnerability of islands to NIS. It was calculated from the residuals to the global relationship between the impact of NIS and their exposure to the islands. The impact of NIS was expressed as the proportion of indigenous species threatened by NIS, and the exposure was the number of invasive NIS per number of native species. The residuals corresponded to the variability in impact, about 60%, that was not explained by exposure. The proportion of endemic species on the islands was positively correlated with the relative intrinsic vulnerability and explained about 60% of its variability. The robust relationship between endemism and intrinsic vulnerability reinforces the role of long-term isolation for the fate of island indigenous species to biological invasions and is useful in identifying vulnerable environments without having a specific invader in mind.

Is invasion success explained by the enemy release hypothesis?

AbstractA recent trend in invasion ecology relates the success of non‐indigenous species (NIS) to reduced control by enemies such as pathogens, parasites and predators (i.e. the enemy release hypothesis, ERH). Despite the demonstrated importance of enemies to host population dynamics, studies of the ERH are split – biogeographical analyses primarily show a reduction in the diversity of enemies in the introduced range compared with the native range, while community studies imply that NIS are no less affected by enemies than native species in the invaded community. A broad review of the invasion literature implies at least eight non‐exclusive explanations for this enigma. In addition, we argue that the ERH has often been accepted uncritically wherever (i) NIS often appear larger, more fecund, or somehow ‘better’ than either congeners in the introduced region, or conspecifics in the native range; and (ii) known enemies are conspicuously absent from the introduced range. However, all NIS, regardless of their abundance or impact, will lose natural enemies at a biogeographical scale. Given the complexity of processes that underlie biological invasions, we argue against a simple relationship between enemy ‘release’ and the vigour, abundance or impact of NIS.

Exposing the Mechanism and Timing of Impact of Nonindigenous Species on Native Species

Exposing the Mechanism and Timing of Impact of Nonindigenous Species on Native Species