Invasive aquatic species discharged through ballast water is one of the most serious problems posed nowadays in the marine environment. This review paper summarizes the available technologies applied ...for ballast water treatment. These technologies can be either port-based or ship-based, with the latter being easier to implement. Special emphasis was given to onboard treatment methods, which can be categorized as physical separation, mechanical or chemical methods. The efficiency of the methods, as well as the capacity of application and the target microorganisms were compiled and are presented in this review. Copyright
Despite the availability of research which has direct applications to environmental management, there is often a disconnect between scientific research and applied management that presents challenges ...for using academic knowledge in day‐to‐day operations by non‐scientists.
A science‐based decision support tool was developed in partnership with Canada's marine authority, Transport Canada, for use by ballast water inspectors in their daily operations to inform prioritization of ships for regulatory compliance inspections.
This science‐based tool combines information on the two primary pathway‐level predictors of species establishment success: environmental matching between source and recipient locations and propagule pressure (introduction effort), to generate risk estimates and relative rankings using data taken directly from ballast water reporting forms submitted by arriving ships.
This tool thus packages the best available scientific knowledge in such a way as to be readily accessible for day‐to‐day decision‐making. While this tool was developed for Canada, it could be applied in any country with very little, if any, modification. This tool can also be updated in the future to incorporate advances in scientific understanding of ballast‐mediated introductions of non‐indigenous species.
Synthesis and applications. Partnerships between scientists and managers are essential for ensuring that best‐available science translates into effective adaptive management. Recognizing a need to inform ballast water management compliance inspections, a tool was created that automatically estimates relative risk of establishment of non‐indigenous species for arriving ships. This information can be used by ballast water inspectors developing priorities for resource‐limited regulatory compliance inspections.
Résumé
Malgré la recherche disponible et ses applications directes sur la gestion de l’environnement, il y a souvent un décalage entre la recherche scientifique et la gestion appliquée. Le défi étant de permettre au personnel non‐scientifique l’utilisation des connaissances issues de la recherche dans ses opérations quotidiennes.
Un outil de support pour prendre de décisions basées sur la science a été développé en partenariat avec l’autorité maritime canadienne, Transport Canada. Cet outil sera utilisé par les inspecteurs des eaux de ballast lors de ses opérations quotidiennes afin de prioriser les navires qui devront passer les inspections de conformité réglementaire.
Cet outil scientifique combine l’information des deux principaux facteurs de prédiction au niveau des voies d’introduction dans le succès de l’établissement des espèces: un couplage environnemental entre les ports d’origine et de destination, ainsi que la pression de propagule (l’effort d’introduction). Ceci afin de générer des estimations des risques et des classements relatifs à l’aide de données tirées directement des formulaires sur l’eau de ballast soumis par les navires à l’arrivée.
Ainsi cet outil regroupe les meilleures connaissances scientifiques disponibles, de manière à être facilement accessible pour la prise de décision au quotidien. Bien que cet outil a été développé par le Canada, il pourrait être utilisé par d’autres pays avec très peu de modifications, voir aucune. Cet outil pourrait être mis à jour à l’avenir afin d’intégrer de nouveaux progrès scientifiques sur l’introduction d’espèces non‐indigènes via les eaux de ballast.
Synthèse et applications. le partenariat entre les scientifiques et les gestionnaires est essentiel pour garantir que les meilleures connaissances scientifiques soient disponibles pour une gestion adaptative efficace. En reconnaissant la nécessité d'éclairer les inspections de conformité sur la gestion des eaux de ballast, un outil a été créé pour estimer automatiquement le risque relatif d'établissement d'espèces non‐indigènes présentes à l'arrivée des navires. Ces informations peuvent être utilisées par les inspecteurs des eaux de ballast qui élaborent les priorités pour les inspections de conformité réglementaire avec des ressources limitées.
Partnerships between scientists and managers are essential for ensuring that best‐available science translates into effective adaptive management. Recognizing a need to inform ballast water management compliance inspections, a tool was created that automatically estimates relative risk of establishment of non‐indigenous species for arriving ships. This information can be used by ballast water inspectors developing priorities for resource‐limited regulatory compliance inspections.
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•The effect of invasive A. armata was analysed.•Exclusion experiments were performed in marine rock pools.•The presence of A. armata impacted significantly macroalgal ...communities.•Mitigation measures may include harvesting for resource use.
Biological invasions represent a threat to ecosystems, through competition and habitat destruction, which may result in significant changes of the invaded community. Asparagopsis armata Harvey 1855 is a red macroalgae (Rodophyta) globally recognized as an invasive species. It is found from the intertidal to shallow subtidal areas, on rock or epiphytic, forming natural vegetation belts on exposed coasts. This study evaluated the variations on native intertidal seaweed and macroinvertebrate assemblages inhabiting rock pools with and without the presence of the invasive macroalgae A. armata. To achieve this, manipulation experiments on Atlantic (Portugal) rock pools were done. Three rock pools were maintained without A. armata by manual removal of macroalgae, and three others were not experimentally manipulated during the study period and A. armata was freely present. In this study the variations between different rock pools were assessed. Results showed different patterns in the macroalgae composition of assemblages but not for the macrobenthic communities. Ellisolandia elongata (J. Ellis & Solander) K.R. Hind & G.W. Saunders 2013 was the main algal species affected by the invasion of A. armata. Invaded pools tended to show less macroalgal species richness, showing a more constant and conservative structure, with lower variation of its taxonomic composition than the pools not containing A. armata, where the variability between samples was always higher. Despite the importance of the achieved results, further data based on observation of long-term series are needed, in order to further understand more severe effects of the invader A. armata on native macroalgal assemblage.
Aim
Identifying niche shifts is key for forecasting future species distributions. Non‐indigenous species (NIS) are one of the greatest threats to biodiversity, and understanding how niche shifts ...affect the spread of NIS is fundamental. Here, we modelled the native and introduced niches, as well as the potential geographical extent of a widely distributed NIS, the Pacific oyster Magallana gigas. We then tested for niche shifts in environmental space and predicted spread under contemporary climate change (CCC) conditions.
Location
Global.
Methods
We used: (1) the two‐dimensional Centroid shift, Overlap, Unfilling and Expansion (COUE) framework and (2) the n‐dimensional hypervolume framework (NDH) to quantify the niches in both analogue and total environmental spaces. Niches were tested for equivalency by comparing the observed and randomized overlaps. Ensemble ecological niche models (ENMs) were then used to predict habitat suitability for the present‐day and two future CCC scenarios.
Results
The NDH framework indicated that the introduced niche of M. gigas has shifted into new environmental conditions compared to the native niche. In contrast, COUE framework implied no niche shift, but the first two dimensions only accounted for a small proportion of the overall environmental variability. Ensemble ENMs revealed suitable areas where M. gigas has yet to be recorded and predicted both a poleward expansion and a tropical contraction of suitable habitat for M. gigas by 2100.
Main conclusions
We found that M. gigas has rapidly shifted its niche in both analogue and non‐analogue environmental spaces since it was first recorded as introduced species over 50 years ago. Our results suggested that niche shifts facilitate both present‐day and future spread of NIS. Additionally, our study demonstrated the importance of modelling niche dynamics in multidimensional space for predicting range shifts of NIS under CCC.
Aim
Retrospective (pre‐ vs. post‐invasion) and cross‐sectional comparisons of ecosystems exposed to high and low bioinvasion pressure, provide an alternative approach to evaluate shifts in biological ...communities associated with non‐indigenous species (NIS) introductions. In this study, we aimed to examine general patterns of change in community composition, structure and function in six well‐studied and globally distributed marine ecosystems that had documented histories of biological invasions.
Location
Global.
Methods
By considering a range of regional datasets and different sampling approaches, we evaluated trends within and among ecosystems by comparing paired measures of community and functional structure in either space or time.
Results
Our analyses revealed different patterns of structural and functional change at ecosystem scales, but direct comparisons across regions were hindered by confounding effects of study designs and other drivers of change. The most prominent shifts in community composition were observed in the retrospective studies, characterised by the greatest relative contribution of NIS. No uniform pattern of change in functional metrics was observed across study regions. However, functional evenness and dispersion showed a tendency to increase in systems under higher invasion pressure, refuting the hypothesis of selective accumulation of specific traits and functional homogenisation within ecosystems exposed to high invasion pressure.
Main Conclusions
Accumulation of NIS within broader communities can be a subtle process, with inherent spatial and temporal variability. Nonetheless, not only do species' proportional contributions to communities change over time in areas subjected to high bioinvasion pressure, but trait profiles can incrementally shift, which alters the original ecology of an area. Planned, long‐term studies that incorporate a range of measures of environmental drivers and ecosystem response are crucial for better understanding of cumulative, community‐level and ecosystem‐scale change associated with biological invasions.
Aim
Effective management of non‐indigenous species requires knowledge of their dispersal factors and founder events. We aim to identify the main environmental drivers favouring dispersal events along ...the invasion gradient and to characterize the spatial patterns of genetic diversity in feral populations of the non‐native pink salmon within its epicentre of invasion in Norway.
Location
Mainland Norway and North Atlantic Basin.
Methods
We first conducted SDM using four modelling techniques with varying levels of complexity, which encompassed both regression‐based and tree‐based machine‐learning algorithms, using climatic data from the present to 2050. Then, we used the triple‐enzyme restriction‐site associated DNA sequencing (3RADseq) approach to genotype over 30,000 high‐quality single‐nucleotide polymorphisms to elucidate the patterns of genetic diversity and gene flow within the pink salmon putative invasion hotspot.
Results
We discovered temperature‐ and precipitation‐related variables drove pink salmon distributional shifts across its non‐native ranges and that climate‐induced favourable areas will remain stable for the next 30 years. In addition, all SDMs identified north‐eastern Norway as the epicentre of the pink salmon invasion, and genomic data revealed that there was minimal variation in genetic diversity across the sampled populations at a genome‐wide level in this region. While utilizing a specific group of ‘diagnostic’ SNPs, we observed a significant degree of genetic differentiation, ranging from moderate to substantial, and detected four hierarchical genetic clusters concordant with geography.
Main Conclusions
Our findings suggest that fluctuations in climate extreme events associated with ongoing climate change will likely maintain environmental favourability for the pink salmon outside its ‘native’/introduced ranges. Locally invaded rivers are themselves potential source populations of invaders in the ongoing secondary spread of pink salmon in Northern Norway. Our study shows that SDMs and genomic data can reveal species distribution determinants and provide indicators to aid in post‐control measures and potentially inferences about their success.
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•Factors shaping non-indigenous species (NIS) richness are tested in the Mediterranean.•There is a higher trend of NIS richness going from east to west in the Mediterranean.•NIS ...richness in marinas is mainly influenced by proximity to other major vectors.•NIS similarities between marinas are more influenced by environmental factors.•The Suez Canal exerts a very strong influence for NIS in Mediterranean marinas.
Rhodoliths, formed by free‐living coralline algae, are distributed worldwide, and the rhodolith beds (RBs) that they form are recognized as structurally complex habitats. In the Mediterranean, they ...are generally distributed in the mesophotic zone, at depths of 30–100 m; so far, only a few shallow RBs (<2 m) have been reported (e.g. Îles Kuriat, Tunisia, and Stagnone Marsala, Italy).
Here a shallow‐water RB located in the Mar Piccolo of Taranto (south‐eastern Italy, Mediterranean Sea) is described. The diversity of associated invertebrates, the rhodolith‐forming algal species, the type of sediments, and the bed extent are characterized.
The RB investigated extends over 5 ha at depths of 0.5–1.5 m. The rhodoliths vary in shape and size, from pralines to large spherical structures, and are formed by a single species, Neogoniolithon brassica‐florida, growing around nuclei of both natural and anthropogenic origin. The associated fauna consisted of 158 taxa, 79 (50%) of which were new basin records. The associated diversity was approximately twice that of the underlying and nearby sediments.
The structural complexity of the RBs promotes biodiversity and provides shelter, food, and a breeding ground for numerous species, including seahorses, which are a conservation priority in this basin.
A lack of biosecurity in the Suez Canal has combined with global warming and other human pressures to cause abrupt changes in the Mediterranean Sea. Throughout this region an influx of species is ...influencing the outcome of efforts to protect and restore nature.
Despite calls for targeted removals of invasive species from protected areas, there is limited information about the effectiveness of this course of action from both an ecological and a socio‐economic perspective. In this study, coordinated removals of lionfish (Pterois miles) by volunteers/scuba divers at three marine protected sites in Cyprus were conducted.
The removal efficiency was monitored using visual‐census surveys and citizen science data. Removals significantly decreased lionfish numbers but long‐term suppression of lionfish would require monitoring and repetition of removals when necessary, since population recovery was sometimes rapid.
Citizen science yielded the data needed to understand lionfish population changes and guide the timing of removal events, but was characterized by large variation and potential outliers, highlighting the need for large sample sizes.
Questionnaire surveys were used to assess the social impact of participation in lionfish removals; these showed that involvement had a strong positive impact on knowledge about lionfish and motivation to support marine conservation activities – the divers were even willing to pay extra to remove lionfish.
Management reforms would be needed to capitalize on this societal motivation, and enable effective lionfish removals by scuba divers, coordinated by competent authorities. The EU aims to protect at least 30% of the marine waters by 2030. Removal events could help shield selected conservation sites from the adverse effects of lionfish and at the same time help establish links with local communities, strengthening the sustainable use of marine systems both at corporate and at societal levels.
Ecology Letters (2010) 13: 937-946 An explanation for successful invasion is that invasive alien species sustain less pressure from natural enemies than co-occurring native species. Using ...meta-analysis, we examined whether invasive species: (1) incur less damage, (2) exhibit better performance in the presence of enemies, and (3) tolerate damage more than native species. Invasive alien species did not incur less damage than native species overall. The performance of invasive alien species was reduced compared to natives in the presence of enemies, indicating the invasive alien species were less tolerant to damage than native species. However, there was no overall difference in performance of invasive alien and native species with enemies present. The damage and degree of reduction in performance of invasive alien relative to native species did not depend on relatedness to natives. Our results suggest aliens may not always experience enemy release, and enemy release may not always result in greater plant performance.
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