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The introduction of biopollutant species challenge ecosystem health and economy in remote islands. Here we checked the advance of invasive fouling species in five French Polynesian islands. Expansion of invasive species (Acantophora spicifera , Bugula neritina , Chthamalus proteus , Dendostrea frons) was detected using individual barcoding (COI for animals, RBLC for algae), and metabarcoding on biofouling (COI and 18S sequences). They were especially abundant in Port Phaeton (Tahiti), Bora Bora and Rangiroa atoll. Chthamalus proteus is a vector of bacterial diseases and may harm native French Polynesian mollusks. Dendostrea frons is a vector of Perkinsus , a parasite to which black pearl oysters, the mainstay of the Polynesian economy, are susceptible. High ecological and epidemiological risks were estimated for C. proteus and D. frons , and ecological risks also for A. spicifera and especially for B. neritina. Strengthening marine biosecurity measures is highly recommended to conserve these unique ecosystems and their associated services. [Display omitted] • Biopollution is a threat for isolated ecosystems of remote islands. • DNA barcoding and metabarcoding biota inventory in French Polynesia ports. • A rapid advance of invasive species transported in fouling is detected. • Epidemiological and ecological risks of four biopollutants are considerable. • A higher control of ship hull fouling is urgently needed. [ABSTRACT FROM AUTHOR]

Macroalgae are able to retain environmental microplastics (MPs). The potential ingestion of MP through Atlantic agar Gelidium corneum and different animal species (hake, glass eels, mussels, topshells, anemones, sea cucumbers) that are seafood resources in Spain, was estimated from published MPs data calculating daily dose and annual ingestion rate. The study region was Asturias (SW Bay of Biscay). Lower MP ingestion rate from algae than from any animal analysed revealed a reduced risk of MP intake, probably because the alga is harvested from quite clean subtidal zones. However, MP bioconcentration in Atlantic agar was higher than in sea cucumbers, mussels or glass eels. Compared with other algae, G. corneum ranked the highest for MP retention rate, perhaps for its intricate branching and gelatinous surface, suggesting a possible use in MP bioremediation. More experimental studies in MP uptake by macroalgae are recommended to understand their implication in the accumulation of this pollutant. • Gelidium corneum is a safe seafood regarding microplastics risk. • Coastal organisms are polluted regardless their bioconcentration capacity. • Topshells, anemones, and mussels exhibit high microplastics concentrations. • G. corneum , holothurians, and hake from offshore are relatively clean. • Red algae with high bioconcentration ability may be used for microplastic remediation. [ABSTRACT FROM AUTHOR]

Early detection of invasive species is crucial to deal effectively with biological invasions in ports, which are hotspots of species introductions. In this study, a simplified end-time PCR methodology conducted on eDNA from water samples was developed for rapid detection of the invasive seaweed Asparagopsis armata (four hours from water collection to result visualization). It was tested dockside in four international Spanish ports in presence of stakeholders, whose feedback was obtained to explore the real applicability of this biotechnology. Although biological invasions were not a main concern for them, results indicate a unanimous approval of the methodology by the stakeholders, having detected the presence of A. armata in three of the ports. Stakeholders suggested further developments for easier application of the tool and multiple species detection, to be adopted for the control of invasive species in ports. • Ports are hotspots for the introduction of new species. • Biological invasions are most effectively treated with early detection. • A fast PCR protocol to detect species eDNA from water samples was developed. • Invasive alga Asparagopsis armata was found from three ports in <4 h. • Stakeholders evaluated positively this tool for rapid species detection. [ABSTRACT FROM AUTHOR]

Plastic pollution is a major ecological catastrophe that endangers vulnerable species. Small plastic fragments and filaments enter the food web in the ocean threatening marine species health. Here microplastics between 0.5 and 5 mm were quantified from eight beaches of southwest Bay of Biscay (Spain) within Natura-2000 Special Protection Areas for birds. Sand samples were taken using a randomized quadrat-based protocol. Between 145 and 382 particles per kg of dry sand were found, which is relatively high in comparison with other European beaches. Microfibers were more abundant than microplastics. PERMANOVA revealed a significant effect of the beach location (inside versus outside the estuary). Open beaches contained a higher microplastic density than sheltered ones suggesting that many beached microplastics come from the ocean. Birds are at risk in the studied protected spaces as revealed from high concentrations of fibres in depositions of European shag and gulls. • Microplastics were quantified in eight Natura 2000 beaches in southwest Bay of Biscay. • Microplastics density was high in comparison with other European beaches. • More microplastics in open than in sheltered beaches suggests MP sea origin • White fibres occurred in all the bird faeces examined, being more abundant in faeces than in the sand. • Seabirds are at risk of microplastic ingestion in the studied area [ABSTRACT FROM AUTHOR]

The invasive Crepidula fornicata caused major problems along the European Atlantic coast, especially in France and Netherlands where high densities leads on changes in the habitat, disturb native marine wildlife as well as it originates competition for space and food. Despite its dangerous invasive nature, regular monitoring to alert about its presence in risk areas, like the south Bay of Biscay (Spain and south France), is not done yet. Here, we developed a species-specific marker to detect the presence of C. fornicata in environmental samples (eDNA) of seawater. The novel C. fornicata specific primers amplified a region of 239 bp within the COI gen. We employed this tool to check its presence in 6 estuaries of the Cantabrian Sea, an area comprised between the Spanish and French limits of the previously reported presence of this limpet in the south Bay of Biscay. The presence of C. fornicata was confirmed in A Coruña (Galicia, Spain), Eo and Villaviciosa estuaries (Asturias, Spain) while it was not detected in Santander, Bilbao (Spain), and Bayonne (France). This new method to detect C. fornicata could be easily implemented in regular monitoring to prevent and manage future invasions of this species. • The first highly sensitive C. fornicata specific marker was designed to detect this invasive limpet in environmental samples. • Six Spanish and French estuaries in the South Bay of Biscay were monitorized to detect Crepidula fornicata employing eDNA. • The results confirmed the presence of this invasive mollusc in Galicia and Asturias, not in Santander, Bilbao and Bayonne. • Spreading of the invasive C. fornicata in European coasts can be regularly monitored using this new molecular tool. [ABSTRACT FROM AUTHOR]

Abstract Coastal litter abundance and its effects have increased for years. Waste reduction is the most effective countermeasure to fight against this problem. Littering attitudes may have an effect on people's involvement in coastal cleanups. In this study, coastal litter perception, awareness about its impact and likely sources were investigated in local population from south Bay of Biscay, Spain. People of different age groups and commitment levels regarding litter were interviewed and their answers compared with data from the area. Results showed differences in perception between volunteers and non-volunteers, but not between children and adults. Interaction effect of age was found for awareness. Volunteers and children tended to erroneously attribute the main litter origin to beachgoers, more than non-volunteers or adults. Our results suggest that encouraging local population to clean beaches would contribute to improve their perception of the problem and their attitudes toward taking action. Highlights • Coastal and marine litter presence depends on human activity and attitudes. • People's actions on the field can determine litter fate and measures effectiveness. • Coastal litter perception determines citizens opinion and their actions. • Volunteering increases perception and measures taken against marine litter. • Encouraging population would contribute to improve coastal and marine conservation. [ABSTRACT FROM AUTHOR]

Marine litter has been considered a potential transport vector of non-indigenous species. In this study developed in Tjärnö (Sweden), at the entry of the Baltic Sea, the communities inhabiting coastal litter and natural substrates ( N  = 5448 macroorganisms) were monitored from eight sites of different ecological conditions. The results showed that litter can support high densities of marine organisms and represent a new habitat in the studied coast. The taxonomic profile of the communities supported by marine litter and hard natural substrate were significantly different. Moreover, opposite to the expectations of reduced diversity in artificial structures, more diverse communities were found on litter. Non-indigenous species were attached mainly to non-plastic artificial materials. From these results it can be concluded that marine litter can significantly alter the biotic composition of coastal ecosystem, representing a shelter for invasive species and diverse natives. [ABSTRACT FROM AUTHOR]

Marine litter is often left by beachgoers. Thus, understanding beachgoers' perception and awareness is important. In this study, the amount and type of litter was measured from nine beaches of central south Bay of Biscay (Spain), and a survey about perception and awareness of the beach littering was conducted among beachgoers. The region could be considered moderately littered compared with other studies, with significant differences among beaches for litter amount and types. Plastic was the most abundant item, followed by fishing gear. Differences among beaches for awareness and litter perception correlated significantly with differences in litter amount. Perception was positively correlated with beach frequentation. Significant gender differences were found, males taking more actions against litter than females regardless how much litter they perceived. These results could be employed for designing campaigns of beach litter treatment and awareness raising, by taking into account local differences detected in this study. [ABSTRACT FROM AUTHOR]

The tubeworm Ficopomatus enigmaticus is a highly invasive species with an increasingly expanding distribution in Europe and America. In port areas it causes damage to structures and sewage systems because it is an active reef builder. Having short generation time and high reproduction capacity it is especially important to detect the species before it is fully settled down. Here we have designed a PCR-based species-specific molecular marker within the Cytochrome Oxidase subunit I gene (COI). The new marker was validated in vitro and from field water samples obtained in southwest Bay of Biscay ports (north of Spain). The species was detected only from eDNA in Villaviciosa port, where it was not found de visu in the intertidal zone and floating structures. Adults were found in the same port one year later as confirmed taxonomically and by conventional barcoding, which confirms the utility of the new eDNA marker for early detection of F. enigmaticus . This new and cheap molecular tool could be used for routine monitoring of coastal areas, in order to early detecting this invasive species. [ABSTRACT FROM AUTHOR]

Floating plastic debris, such as bottles and fishing gear, is a shelter for different species in the oceans. Litter may therefore help the spread of non-indigenous species (NIS). Here we have challenged the idea of using the abundance of marine litter present in a zone to estimate the risk of NIS introduction. To test this, a targeted sampling of plastic bottles and fishing gear (ropes and nets) was performed along 22 beaches from the Cantabrian coast where ports have been reported as a source of biological invasions. All items with attached organisms were collected and recorded. Genetic barcoding was used to ascertain the species and identify NIS. In total 17 species attached to plastic bottles and fishing gears were identified. Three of them, found on the two types of items, are catalogued as invasive species: Austrominius modestus ; Magallana gigas ; and, Amphibalanus amphitrite . Prevalence and mean intensity of non-indigenous biota on plastic bottles and fishing gear were not significantly different. The abundance of barnacles in litter was significantly correlated with that found from ports in the same region. The results suggest that ropes are able to transport different marine organisms and NIS as plastic bottles do. Monitoring biota on marine litter could serve as an additional tool for NIS detection. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) affect both marine and terrestrial biota worldwide for their harmful effects, which range from physical cell damage to physiological deterioration. In this research, microplastics were quantified from gills, liver and muscle of demersal Benguela hakes Merluccius polli (n = 94), caught by commercial trawling from northwest African waters. Plastic polymers were identified using Fourier Transformed-infraRed spectroscopy (FT-iR). Fulton's k condition factor and the degree of DNA degradation in liver were measured. None of the individuals were free of MPs, whose concentration ranged from 0.18 particles/g in muscle to 0.6 in liver. Four hazardous polymers were identified: 2-ethoxyethylmethacrylate, polyester, polyethylene terephthalate, and poly-acrylics. MP concentration in liver was correlated negatively with the condition factor, suggesting physiological damage. Positive association of MP concentration and liver DNA degradation was explained from cell breakage during trawl hauls during decompression, suggesting an additional way of MPs harm in organisms inhabiting at great depth. This is the first report of potential MPs-driven damage in this species; more studies are recommended to understand the impact of MP pollution on demersal species. • Microplastics were counted from gills, liver and muscle in the African hake Merluccius polli. • Microplastics content in liver was negatively associated with hake's condition factor. • DNA degradation in liver suggests additional microplastics damage in demersal species. • Microplastics pollution may threaten fishing resources through poorer fish condition. [ABSTRACT FROM AUTHOR]

Emerging microplastics (MP) pollution is one of the biggest threats for the oceans today. Consumers could reduce MP pollution adopting R-behaviors such as reducing consumption of plastic, refusing products with MP, replacing them for green products, and recycling. Here we tested the efficiency of online nudges (images and short messages) for promoting MP-conscious behavior in Spain (n = 671). The perceived level of environmental responsibility and the willingness to adopt R-behaviors were measured. Messages about seafood with MP and plastic-polluted marine environment were more efficient than images of animals killed by plastics. Feeling responsible for MP pollution predicted R-behavior intention. Women would adopt more R-behaviors than men, while men were more sensitive than females to the proposed nudges. Raising the sense of environmental responsibility would be priority in education campaigns. For different cultural sensitivities to animal suffering, evoking environmental health instead of threats to wildlife would be generally recommended. [Display omitted] • Microplastic pollution is an increasing threat for the ocean. • Plastic and microplastics consumption should be cut down. • Images of microplastic-polluted seafood increase the willingness of R-behavior. • Men are more sensitive to environmental messages than females. • Responsibility for the ocean predicts R-behavior and should be encouraged. [ABSTRACT FROM AUTHOR]

Microplastics pollution is widespread throughout the world, affecting all marine ecosystems and their organisms. The red alga Gelidium sp. is the source of best quality agar and is directly consumed as seafood in many countries. Here we quantified microplastics in Gelidium corneum harvested along the Asturias coast (southwest Bay of Biscay) from locations differently affected by factors that influence microplastics concentration like substrate size, ports, rivers, etc. Results showed that G. corneum collected near sandy substrates accumulates more microplastics than those from rocks, suggesting that the substrate's dynamics is key to allow microplastics to reach these algae and enter the human diet. Considering their composition, polyethyleneimine and polyester were identified and classified as harmful according to the European Chemicals Agency. The polyethyleneimine is present in the 28,6 % analysed from the algae and may pose a risk to consumers. The amount of microplastics potentially ingested by consumers would be lower than mussels and eels of the same region; but could potentially increase in agar if microplastics are not retained during processing. More research to identify microplastics sources and measures to prevent them in coastal areas are recommended. [Display omitted] • MP are present in all investigated ecosystems and their organisms, as well as transferred throughout the food web. • MP are in beaches; their composition can help to identify the sources and risks. • G. corneum near sandy substrates had more microplastics than those from rocks. • Dominant colours were white/transparent and blue in algae, and black in water. In G. corneum only fibers were found. • Polyethyleneimine (PEI) is the main risk for consumer in this region, corresponding to 28.6%. [ABSTRACT FROM AUTHOR]

Ports are gateways for many marine organisms transported by ships worldwide, especially non-indigenous species (NIS). In this study carried out in North Iberian ports (Cantabrian Sea, Bay of Biscay) we have observed 38% of exotic macroinvertebrates. Four species, namely the barnacle Austrominius modestus , the tubeworm Ficopomatus enigmaticus , the Pacific oyster Crassostrea gigas and the pygmy mussel Xenostrobus securis , exhibited clear signs of invasiveness. A total of 671 barcode (cytochrome oxidase subunit I or 18S rRNA) genes were obtained and confirmed the species status of some cryptic NIS. Negative and significant correlation between diversity estimators of native biota and proportion of NIS suggests biotic resistance in ports. This could be applied to management of port biota for contributing to prevent the settlement of biopollutants in these areas which are very sensitive to biological invasions. [ABSTRACT FROM AUTHOR]

Early detection of dangerous exotic species is crucial for stopping marine invasions. The New Zealand pygmy mussel Xenostrobus securis is a problematic species in coasts of temperate regions in the northern hemisphere. In this study we have controlled a population of this invader that recently expanded in a north Iberian estuary with both a participatory approach involving researchers and citizens, and employing a sensitive eDNA-based tool to monitor the population expansion in the estuary. Results demonstrate successful eradication of pygmy mussels in the outer part of the estuary with citizen science and the practical utility of eDNA for controlling biological invasions. [ABSTRACT FROM AUTHOR]

DNA efficiently contributes to detect and understand marine invasions. In 2014 the potential biological pollutant pygmy mussel ( Xenostrobus securis ) was observed for the first time in the Avilés estuary (Asturias, Bay of Biscay). The goal of this study was to assess the stage of invasion, based on demographic and genetic (DNA Barcoding) characteristics, and to develop a molecular tool for surveying the species in environmental DNA. A total of 130 individuals were analysed for the DNA Barcode cytochrome oxidase I gene in order to determine genetic diversity, population structure, expansion trends, and to inferring introduction hits. Reproduction was evidenced by bimodal size distributions of 1597 mussels. High population genetic variation and genetically distinct clades might suggest multiple introductions from several source populations. Finally, species-specific primers were developed within the DNA barcode for PCR amplification from water samples in order to enabling rapid detection of the species in initial expansion stages. [ABSTRACT FROM AUTHOR]

In this study, high-throughput sequencing (HTS) metabarcoding was applied for the surveillance of plankton communities within the southeastern (SE) Baltic Sea coastal zone. These results were compared with those from routine monitoring survey and morphological analyses. Four of five nonindigenous species found in the samples were identified exclusively by metabarcoding. All of them are considered as invasive in the Baltic Sea with reported impact on the ecosystem and biodiversity. This study indicates that, despite some current limitations, HTS metabarcoding can provide information on the presence of exotic species and advantageously complement conventional approaches, only requiring the same monitoring effort as before. Even in the currently immature status of HTS, this combination of HTS metabarcoding and observational records is recommended in the early detection of marine pests and delivery of the environmental status metrics of nonindigenous species. [ABSTRACT FROM AUTHOR]

Transfer of organisms with ships’ ballast water is recognized as a major pathway of non-indigenous species introduction and addressed in a few recent legislative initiatives. Among other they imply scientific and technical research and monitoring to be conducted in a efficient and reliable way. The recent development of DNA barcoding and metabarcoding technologies opens new opportunities for biodiversity and biosecurity surveillance. In the current study, the performance of metabarcoding approach was assessed in comparison to the conventional (visual) observations, during the en route experimental ballast water survey. Opportunities and limitations of the molecular method were identified from taxonomical datasets rendered by two molecular markers of different degree of universality – the universal cytochrome oxydase sub-unit I gene and a fragment of RuBisCO gene. The cost-efficacy and possible improvements of these methods are discussed for the further successful development and implementation of the approach in ballast water control and NIS surveillance. [ABSTRACT FROM AUTHOR]

The BluefishPomatomus saltatrixis a highly migratory species that is composed of different stocks and populations along its nearly cosmopolitan distribution. The Bluefish is the only member of its genus and family, and high migration rates could prevent vicariant speciation across its wide geographical distribution. However, the extent of gene flow between distant populations is unknown. We employed two mitochondrial genes (cytochrome-coxidase subunit I and cytochromeb) and eight nuclear microsatellite loci to study population structure and infer dispersal of this important commercial and recreational fish across its Northern Hemisphere distribution. Higher gene flow estimates for nuclear loci (of biparental inheritance) than for mitochondrial loci (of maternal inheritance) suggested sex-biased dispersal, which could be explained by greater female homing or fidelity to spawning sites and greater dispersal of males. Males could contribute more to transoceanic connectivity of Bluefish populations in the North Atlantic Ocean, thus shaping the observed pattern of spatial genetic structure of the Bluefish in its Northern Hemisphere distribution. Received February 1, 2014; accepted June 9, 2014 [ABSTRACT FROM AUTHOR]

Highlights: [•] Impact of Prestige oil spill was studied on two sympatric megrim fish populations. [•] Samples before and nine years after the accident were genetically analyzed. [•] A large proportion of post-F1 interspecific hybrids was found in the polluted area. [•] Both species’ population structure was altered by introgression of foreign alleles. [•] The spillage likely promoted a hybrid zone for Lepidorhombus in the areas affected. [ABSTRACT FROM AUTHOR]

Abstract: Population structuring based on mitochondrial DNA variation along the rural landscape of the Trubia valley in North Iberia revealed significant association between road density and genetic distance between populations of two amphibian species, the midwife toad Alytes obstetricans and the palmate newt Lissotriton helveticus. Traffic calming (concentration of flows on minor rural roads at a few highways to decrease volumes and speeds) near urban settlements mitigates the population fragmentation of L. helveticus but not that of A. obstetricans, indicating that even small roads with low-intensity traffic act as barriers for the latter species. We suggest that the construction of passages for amphibians across rural roads would potentially mitigate population fragmentation of endangered species like the anuran A. obstetricans. [Copyright &y& Elsevier]

Populations of southern European Atlantic salmon Salmo salar are subjected to exploitation by sportfishing and exhibit evidence of dramatic catch reduction for the same fishing effort over recent history. We employed nine microsatellite loci as markers to estimate effective population sizes of Atlantic salmon in five rivers of northern Spain for comparison with 1990s data describing the same populations; marked declines in effective population sizes over the last decade were detected, and a reduced census size is proposed to be one of the probable causes. These estimates highlight the endangered status of the Atlantic salmon populations in northern Spain. A reduction in fishing effort and an increase in protective measures are recommended for the conservation of these fragile populations at the southernmost edge of the species' natural distribution. [ABSTRACT FROM AUTHOR]

Populations of Atlantic salmon Salmo salar at the edge of the species' distribution are the most vulnerable to environmental changes. Those inhabiting southern European rivers are expected to be particularly affected by global warming. However, they are exploited as a very valuable resource for the region, attracting tourism and generating substantial income. In the central part of northern Spain (Asturias), there is a long tradition of sport fisheries (angling). The first salmon caught in a river each year is called the 'campanu.' Analysis of a 50-year time series demonstrates that the run timing of the Asturian Atlantic salmon has changed over this period, as inferred from significant delays in the date of capture of the campanu. Average campanu weight has experienced a parallel significant decrease but age has not changed, indicating diminution of salmon condition. These changes are statistically associated with an increase in regional temperature, there being a minor effect of the global climate North Atlantic Oscillation index. Negative effects of high temperatures on salmon run and feeding, together with long migratory routes, may explain these results. [ABSTRACT FROM AUTHOR]

Mislabeling of North American merlucciid hakes in stock surveys and commercial market samples was detected by employing nuclear 5S ribosomal DNA (rDNA) and mitochondrial cytochrome b variation as molecular markers. Results showed that offshore hake is sold in European markets but is labeled as the morphologically similar silver hake , which is the target species of the fishery. This suggests that offshore hake may be inadvertently included within silver hake landings, as the two species overlap in the southern area of silver hake distribution (approximately 41°-35°N latitude near North American coasts). An inexpensive and technically easy technique based on polymerase chain reaction (PCR) amplification of a fragment of 5S rDNA and visualization of PCR products in agarose gels is recommended for routine species assignation in landings for purposes of exploitation estimates and for authentication of commercial hake species. [ABSTRACT FROM AUTHOR]

Coastal areas are environments of high diversity and severely threatened by hazards as marine litter and biological invasions. Citizens' knowledge and awareness are drivers of changes needed to improve environment conservation. Density both of litter and IAS Cortaderia selloana were measured from six beaches in southwest Bay of Biscay along with awareness of inhabitants of the zone using a social survey. Relationship between beach littering, alien invasion and perception and awareness of adults and students were assessed. Litter levels were associated with port presence and showed relationship between environmental degradation, IAS and litter accumulation. Adults were more aware about both issues and their perception of litter and plant invasion were positively correlated. Results suggest enhancing marine awareness, with more effort addressed specifically to students. There is a misperception of the real magnitude of IAS and litter impacts that should be approached improving awareness about this topics in the younger generations. [ABSTRACT FROM AUTHOR]

Brown trout, Salmo trutta, European eel, Anguilla anguilla, and European minnow, Phoxinus phoxinus, three fish species inhabiting European freshwater ecosystems, were evaluated for their use as in situ pollution biomarkers using the micronucleus test in renal erythrocytes. Experimental exposure (by immersion) to different concentrations of cyclophosphamide, colchicine, and cadmium showed that brown trout are more sensitive to the three compounds than minnows and eels. In situ surveys of wild freshwater ecosystems with different levels of pollution showed that minnows and eels living in polluted sites do not present higher micronuclei averages than those caught in clean rivers systems, whereas micronuclei are induced in brown trout inhabiting polluted sites. Our results demonstrated the suitability of brown trout for in situ biomonitoring of freshwater ecosystems as well as for laboratory tests using the micronucleus test. [Copyright &y& Elsevier]

Mussels Mytilus edulis were sampled at increasing distances from urban effluents in two very different locations, Gijon (northern Spain, Europe, 43°N) and Puerto Madryn (Argentina, South America, 43°S), and from an industry effluent in Puerto Madryn. The micronucleus test was performed on branchial cells. For the three situations, a statistically significant negative association was found between the distance of sampling site from the effluent and the mean number of micronuclei per 1000 cell counts, in a range of distances as short as 300 m. The micronucleus test in Mytilidae, here revealed to be sensitive enough to monitor urban pollution, is proposed for routine surveys of pollution as a bioindicator of choice for coastal ecosystems. [Copyright &y& Elsevier]

We examined the genetic structure of two North American populations of Atlantic salmon Salmo salar, those of the Connecticut and Penobscot rivers. The native population in the Connecticut River (at the southern edge of the species' natural distribution) was extirpated nearly 200 years ago. A restoration population was founded about 30 years ago with individuals from the Penobscot River, 400 km north of the Connecticut River. We investigated the current variation of both populations at enzymatic and microsatellite loci to assess the genetic changes that have occurred in the Connecticut River population with respect to the predominant (brood source) population. Significant differences between the two stocks were found at both enzyme and microsatellite loci and in the age of maturity of returning adults. [ABSTRACT FROM AUTHOR]

Hybridization between Atlantic salmon Salmo salar and brown trout S. trutta is frequently reported, and the role of mature male Atlantic salmon parr has been suspected but never proven. Salmon fry were stocked into a headwater tributary stream of the Connecticut River, where no adult salmon are present. The stream has a self-sustaining population of brown trout. Enzyme electrophoresis revealed the presence of one hybrid (0.81% of the sampled population). The maternal species was identified as brown trout; therefore, the only possibility for the male parent was that it was a mature male Atlantic salmon parr. This is the first direct evidence of parr producing hybrid offspring in a totally natural setting and in the absence of any sea-return salmon. [ABSTRACT FROM AUTHOR]

Electronic waste sites are rich in heavy metals contained in electronic and electric equipment waste and pose a risk of pollution if metals enter in the environment nearby. The Korle lagoon, located in the center of Accra, is receiving waste effluents from industries, households and the adjacent e-waste burning site Agbogbloshie which is the biggest in the country. Thus, the risk of heavy metal contamination of the water body and subsequent uptake in the aquatic food chain is particularly relevant. Small-scale fishing, not entering the commercial chain, occurs in the lagoon despite its consideration of biologically dead. We assessed if the exposure to heavy metals through these fish consumption is posing higher health risks than fish sold on Ghanaian markets. Using ICP-MS technology, we quantified concentrations of As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn in fish caught from the Korle Lagoon (Trachinotus ovatus , Mugil curema and Mugil cephalus) and compared them to fish from the Tema Newtown fishing market (Scomber colias , Pseudotolithus senegallus). Cobalt and lead concentrations, typical e-waste metals, were higher in fish from the Korle lagoon, even though they were of lower trophic level. Calculated risk indices revealed risk of elevated arsenic and mercury exposure, particularly through T. ovatus from the Korle lagoon, if consumed daily as it is common in the region. This study suggests the need of monitoring programs of Ghanaian catch, with a special focus in environmental risk areas like Korle lagoon to ensure human food safety. [Display omitted] • Korlee lagoon is not a biologically dead water body. • Higher WEEE metal content in fish living near e-waste sites • There is an important cobalt pollution in the fishes from in the lagoon. • Health risk assessment shows that consumption of standard meal sizes of analyzed species is totally discouraged. • Monitoring fish catches to ensure nutritional supply and prevent health hazards is necessary. [ABSTRACT FROM AUTHOR]

While levels of microplastics and other pollutants keep increasing in all coastal habitats, seafood is being eaten all over the world. In this research, three edible species were sampled from six points along the central north coast of Spain: Actinia equina anemones and Phorcus lineatus and Steromphala umbilicaris topshells (N = 100). Putative microplastics (N = 2157) were identified, counted, and many analyzed through FT-IR spectroscopy. Herbivorous topshells contained significantly more microplastics than carnivorous anemones. The most common particles were fibers, with transparent, blue and black as most prominent colours. Plastics included PE, polyester, PET, PP, nylon, PS, PVB and acrylic fibers. The sampled items contained several harmful compounds, including PTTC of which even one particle could be fatal if inhaled. This highlights the urgent need for studies regarding the safety of seafood. • Microplastics of/with harmful materials in Bay of Biscay anemones and topshells • Topshells contain more microplastics than anemones. • Transparent, black and blue fibers are predominant. • Anthropogenically modified cellulose is the commonest material. • Harmful compounds were: 7 irritant, 4 toxic, 3 carcinogenic and 1 mutagenic. [ABSTRACT FROM AUTHOR]