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In fisheries, operational management units and biological data often do not coincide. In many cases, this is not even known due to the lack of information about a species' population structure or behaviour. This study focuses on two such species, the common ling Molva molva and the blue ling M. dypterygia , two Northeast Atlantic gadoids with overlapping geographical distribution, but different depth habitats. Heavily exploited throughout their ranges, with declining catches, little is known about their population structure. Genotyping-by-sequencing at thousands of genetic markers indicated that both species are separated into two major groups, one represented by samples from the coasts of western Scotland, Greenland, and the Bay of Biscay and the other off the coast of Norway. This signal is stronger for the deeper dwelling blue ling, even though adult dispersal was also identified for this species. Despite small sample sizes, fine-scale patterns of genetic structure were identified along Norway for common ling. Signatures of adaptation in blue ling consisted in signs of selections in genes involved in vision, growth, and adaptation to cold temperatures. [ABSTRACT FROM AUTHOR]

Sea trout ( Salmo trutta) originating from small coastal streams can be found at sea throughout the year, in contrast to conspecifics from larger rivers, which typically spend the autumn and winter in fresh water. Such an extended marine stay has been observed in coastal Skagerrak. We studied the seasonal variation in marine growth of Skagerrak sea trout based on scale increment patterns and body lengths of 563 individuals captured at sea. Growth, measured as increased body length, was rapid during summer while there was no evidence for continued growth during autumn and winter. Growth decreased with increasing age of the fish. Our results suggest that coastal Skagerrak is an important feeding area for sea trout during summer, and that an extended marine stay during autumn and winter may have trade-off benefits other than somatic growth. Alternative benefits might be increased winter survival and decreased migratory costs of juvenile fish. [ABSTRACT FROM AUTHOR]

Small-scale spatial variation in life history was found among genetically distinct local populations of Atlantic cod Gadus morhua from the Norwegian Skagerrak coast. Among populations, age at 50% maturity varied from 2·6 to 3·8 years, total ( LT) length at 50% maturity from 35 to 60 cm, annual survival from 33 to 64%, mean LT at age 4 years from 43 to 63 cm, and mean backcalculated LT at age 1 year from 8 to 12 cm. [ABSTRACT FROM AUTHOR]

Juvenile and adult anadromous trout Salmo trutta utilize the sea for feeding during the winter in the Skagerrak. This finding conflicts with the traditional view that anadromous trout overwinter in fresh water. Adults, just prior to spawning, were captured at sea in October to December, and spent fish were caught at sea from October to April, showing that the fish may leave the stream and move to sea just after spawning and spend the winter there. During mid-winter (January to February), the feeding probability (chance of finding a fish with food in its stomach) increased markedly with increasing body length, with no similar effect during early and late winter (October to December and March to April). Among individuals with food in their stomach (72·5%), there was no evidence for variation in feeding intensity [stomach fullness = (mass of stomach content)(fish body mass)−1] among early, mid-, and late winter. [ABSTRACT FROM AUTHOR]

Abstract Compared with many terrestrial and freshwater environments, dispersal and interbreeding is generally much less restricted in the marine environment. We studied the tendency for a marine species, the Atlantic cod, to be sub-structured into genetically differentiated populations on a fine geographical scale. We selected a coastal area free of any obvious physical barriers and restricted sampling to a 300-km region, well within the dispersal ability of this species. Screening 10 polymorphic microsatellite loci in 6 samples we detected a weak, but consistent, differentiation at all 10 loci. The average F ST over loci was small (0.0023) but highly significant statistically, demonstrating that genetically differentiated populations can arise and persist in the absence of physical barriers or great distance. We found no geographical pattern in the genetic differentiation and there was no apparent trend of isolation by distance along the coastline. These findings lend support to the notion that low levels of differentiation are due to passive transport of eggs or larvae by the ocean currents rather than to adult dispersal, the latter being strongly dependent on distance. [ABSTRACT FROM AUTHOR]

Fifty-six patients with angina pectoris on effort participated in a 28-day study comparing a transdermal nitroglycerin system (TNS) against placebo. The protocol was based on a regular double-blind multi-crossover pattern. The variables recorded included daily sublingual nitroglycerin requirement, daily anginal attack frequency, and a subjective patient evaluation of each day on a visual analog scale. TNS dosage ranged from 10 cm (5 mg per 24 h) to 60 cm (30 mg per 24 h) based on the patient's dosage prior to commencement of the study. All other medication was continued unchanged. The results demonstrate improvement on active therapy in the patient group using ≥20 cm TNS whereas no significant improvement in patients using 10 cm TNS was seen. In the higher dose group, the mean number of daily anginal attacks was 2.5 on placebo and 1.4 on active therapy (P<0.0001). Corresponding mean daily sublingual nitroglycerin requirement was 3.6 on placebo and 2.3 on active therapy (P<0.0001). Although TNS therapy was associated with significant improvement in the group using the higher dosage, the results suggest the development of tolerance on active therapy. The possibility of rebound effect and the absence of demonstrable efficacy in the low dose group require further investigation. [ABSTRACT FROM PUBLISHER]

In this article three main approaches to the concept of globalization are distinguished between, and it is demonstrated that arguments in the ‘new’ debate on globalization and the sss‘old’ debate on a new international division of labour are in many respects similar. [ABSTRACT FROM PUBLISHER]

Effects of N addition and drought on ectomycorrhizae of Norway spruce trees were investigated in an outdoor pot lysimeter study. Three levels of N were applied as ammonium nitrate in irrigation water for five years; ambient rainwater (N0) and 5 (N5) and 15 (N15) times this Nconcentration. Mean annual N addition during the five years corresponded to 5, 27 and 82 kg-ha-1-y- 1 for the N0, N5 and N15 treatments, respectively. During the third and fifth growthseasons two levels (lengths) of drought were artificially induced inaddition to a watered control. Soil cores taken from each pot lysimeter were analyzed for mycorrhizal colonization and ectomycorrhizae were categorized according to macroscopic morphology. Drought decreasedmycorrhizal colonization significantly. There was a significant interaction of drought and N effects on reduction of the mycorrhizal colonization. Although all of the mycorrhiza types were influenced by drought, only Cenococcum geophilum showed a significant change. N treatment alone did not show any significant effect either on mycorrhizal colonization or mycorrhizal types. [ABSTRACT FROM AUTHOR]

During periods of environmental change, genetic diversity in foundation species is critical for ecosystem function and resilience, but it remains overlooked in environmental monitoring. In the Baltic Sea, a key species for monitoring is the brown seaweed Fucus vesiculosus, which forms sublittoral 3D habitats providing shelter and food for fish and invertebrates. Ecological distribution models predict a significant loss of Baltic F. vesiculosus due to ocean warming, unless populations can adapt. Genetic variation and recombination during sexual reproduction are essential for adaptation, but studies have revealed large-scale clonal reproduction within the Baltic Sea. We analysed genome-wide single nucleotide polymorphism (SNP) data from the east Atlantic, the "Transition zone," and the Baltic Sea, and found a mosaic of divergent lineages in the Baltic Sea, contrasting an outside dominance of a few genetic groups. We determined that the previously described endemic species Fucus radicans is predominantly a large female clone of F. vesiculosus in its northern Baltic distribution. In the two Estonian sites, however, individuals earlier referred to as F. radicans are sexually and reproductively isolated from Baltic F. vesiculosus, revealing a separate lineage that may have diverged long before the formation of the Baltic Sea. Monitoring Baltic Fucus without considering this genetic complexity will fail to prioritise populations with adaptive potential to new climate conditions. From our genomic data, we can extract informative and diagnostic genetic markers that differentiate major genetic entities. Such a SNP panel will provide a straightforward tool for spatial and temporal monitoring and informing management decisions and actions., (© 2025 The Author(s). Molecular Ecology published by John Wiley & Sons Ltd.)

The European Commission mandated EFSA to assess the toxicity of bromide, the existing maximum residue levels (MRLs), and possible transfer from feed into food of animal origin. The critical effects of bromide in experimental animals are on the thyroid and central nervous system. Changes in thyroid hormone homeostasis could result in neurodevelopmental toxicity, among other adverse effects. Changes in thyroid hormone concentrations and neurophysiological parameters have also been observed in experimental human studies, but the evidence was limited. Dose-response modelling of decreased blood thyroxine concentrations in rats resulted in a reference point of 40 mg/kg body weight (bw) per day. The Scientific Committee established a tolerable daily intake (TDI) of 0.4 mg/kg bw per day and an acute reference dose (ARfD) of 0.4 mg/kg bw per day to protect against adverse neurodevelopmental effects. The TDI value is supported by the results of experimental human studies with a NOAEL of 4 mg/kg bw per day and 10-fold interindividual variability. The TDI and ARfD are considered as conservative with 90% certainty. Insufficient evidence related to the toxicological effects of bromide was available for animals, with the exception of dogs. Therefore, the reference point of 40 mg/kg bw per day was extrapolated to maximum safe concentrations of bromide in complete feed for other animal species. Bromide can transfer from feed to food of animal origin, but, from the limited data, it was not possible to quantify the transfer rate. Monitoring data exceeded the current MRLs for some food commodities, generally with a low frequency. A conservative safety screening of the MRLs indicated that the TDI and ARfD are exceeded for some EU diets. Dietary exposure assessment for animals was not feasible due to insufficient data. The Scientific Committee recommends data be generated to allow robust dietary exposure assessments in the future, and data that support the risk assessment., (© 2025 European Food Safety Authority. EFSA Journal published by Wiley‐VCH GmbH on behalf of European Food Safety Authority.)

Knowledge of functional dispersal barriers in the marine environment can be used to inform a wide variety of management actions, such as marine spatial planning, restoration efforts, fisheries regulations, and invasive species management. Locations and causes of dispersal barriers can be studied through various methods, including movement tracking, biophysical modeling, demographic models, and genetics. Combining methods illustrating potential dispersal, such as biophysical modeling, with realized dispersal through, e.g., genetic connectivity estimates, provides particularly useful information for teasing apart potential causes of observed barriers. In this study, we focus on blue mussels ( Mytilus edulis ) in the Skagerrak-a marginal sea connected to the North Sea in Northern Europe-and combine biophysical models of larval dispersal with genomic data to infer locations and causes of dispersal barriers in the area. Results from both methods agree; patterns of ocean currents are a major structuring factor in the area. We find a complex pattern of source-sink dynamics with several dispersal barriers and show that some areas can be isolated despite an overall high dispersal capability. Finally, we translate our finding into management advice that can be used to sustainably manage this ecologically and economically important species in the future., Competing Interests: Pierre De Wit is an Editorial Board member of Evolutionary Applications and a co‐author of this article. To minimize bias, they were excluded from all editorial decision‐making related to the acceptance of this article for publication., (© 2024 The Author(s). Evolutionary Applications published by John Wiley & Sons Ltd.)

The absence of functional top predators has been proposed as a mechanism acting to shape fish assemblages in temperate marine ecosystems, with cascading effects on lower trophic levels. We explore this scenario by comparing the trophic and functional status of fish assemblages in Norwegian marine national parks, open to fishing, to a nearby coastal seascape that harbors a system of marine protected areas (MPAs) including a no-take zone. Demersal fish assemblages were sampled using fyke nets over three consecutive seasons. Atlantic cod ( Gadus morhua ) is potentially a dominant top predator in this ecosystem, and historically, this and other gadids have been targeted by the full range of former and present fisheries. In the present study, we find that average body size of the Atlantic cod was significantly larger in the zoned seascape compared to the unprotected areas (mean ± SD: 36.6 cm ± 14.38 vs. 23.4 ± 7.50; p  < .001) and that the unprotected seascape was characterized by a higher abundance of mesopredator fish species. These observations are consistent with the hypothesis that the protection of top predators within MPAs aids to control the mesopredator populations and provides empirical support to the notion that the present state of many coastal fish assemblages is driven by mesopredator release linked to functional depletion of large top predators., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Range expansions can lead to increased contact of divergent populations, thus increasing the potential of hybridization events. Whether viable hybrids are produced will most likely depend on the level of genomic divergence and associated genomic incompatibilities between the different entities as well as environmental conditions. By taking advantage of historical Baltic cod ( Gadus morhua ) otolith samples combined with genotyping and whole genome sequencing, we here investigate the genetic impact of the increased spawning stock biomass of the eastern Baltic cod stock in the mid 1980s. The eastern Baltic cod is genetically highly differentiated from the adjacent western Baltic cod and locally adapted to the brackish environmental conditions in the deeper Eastern basins of the Baltic Sea unsuitable for its marine counterparts. Our genotyping results show an increased proportion of eastern Baltic cod in western Baltic areas (Mecklenburg Bay and Arkona Basin)-indicative of a range expansion westwards-during the peak population abundance in the 1980s. Additionally, we detect high frequencies of potential hybrids (including F1, F2 and backcrosses), verified by whole genome sequencing data for a subset of individuals. Analysis of mitochondrial genomes further indicates directional gene flow from eastern Baltic cod males to western Baltic cod females. Our findings unravel that increased overlap in distribution can promote hybridization between highly divergent populations and that the hybrids can be viable and survive under specific and favourable environmental conditions. However, the observed hybridization had seemingly no long-lasting impact on the continuous separation and genetic differentiation between the unique Baltic cod stocks., Competing Interests: The authors declare no conflicts of interest., (© 2023 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd.)

Temperature profoundly affects ectotherm physiology. Although differential thermal responses influence fitness, thus driving population dynamics and species distributions, our understanding of the molecular architecture underlying these responses is limited, especially during the critical larval stage. Here, using RNA-sequencing of laboratory-reared Atlantic cod (Gadus morhua) larvae of wild origin, we find changes in gene expression in thousands of transcripts consistent with a severe cellular stress response at both ambient and projected (+2°C and +4°C) temperatures. In addition, specific responses to stress, heat, and hypoxia were commonly identified in gene ontology enrichment analyses and 33 of the 44 genes comprising the minimum stress proteome of all organisms were upregulated. Earlier onset of the stress response was evident at higher temperatures; concomitant increased growth and mortality suggests a reduction in fitness. Temporal differences in gene expression levels do not correspond to differences in growing degree days, suggesting negative physiological consequences of warming beyond accelerated development. Because gene expression is costly, we infer that the upregulation of thousands of transcripts in response to warming in larval cod might act as an energetic drain. We hypothesize that the energetically costly stress response, coupled with increased growth rate at warmer temperatures, leads to faster depletion of energy reserves and increased risk of mortality in larval cod. As sea surface temperatures continue to rise over the next century, reduced fitness of Atlantic cod larvae might lead to population declines in this ecologically and socioeconomically important species. Further, our findings expand our understanding of transcriptomic responses to temperature by ectothermic vertebrate larvae beyond the critical first-feeding stage, a time when organisms begin balancing the energetic demands of growth, foraging, development, and maintenance. Linking the molecular basis of a thermal response to key fitness-related traits is fundamentally important to predicting how global warming will affect ectotherms., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology.)

Identifying how physical and biotic factors shape genetic connectivity among populations in time and space is essential to our understanding of the evolutionary trajectory as well as the management of marine species. Atlantic cod is a widespread and commercially important marine species displaying several ecotypes with different life history strategies. Using three sets of SNPs: neutral, informative, and genome-inversion linked, we studied population genetic structure of ~2500 coastal Atlantic cod (CC) from 40 locations along Norway's 2500 km coastline, including nine fjords. We observed: (1) a genetic cline, suggesting a mechanism of isolation by distance, characterized by a declining F ST between CC and North East Arctic Cod (NEAC-genetically distinct migratory ecotype) with increasing latitude, (2) that in the north, samples of CC from outer-fjord areas were genetically more similar to NEAC than were samples of CC from their corresponding inner-fjord areas, (3) greater population genetic differentiation among CC sampled from outer-fjord areas along the coast, than among CC sampled from their corresponding inner-fjord areas, (4) genetic differentiation among samples of CC from both within and among fjords. Collectively, these results permit us to draw two main conclusions. First, that differences in the relative presence of the genetically highly distinct, migratory ecotype NEAC, declining from north to south and from outer to inner fjord, plays the major role in driving population genetic structure of the Norwegian CC. Second, that there is limited connectivity between CC from different fjords. These results suggest that the current management units implemented for this species in Norway should be divided into smaller entities. Furthermore, the situation where introgression from one ecotype drives population genetic structure of another, as is the case here, may exist in other species and geographical regions, thus creating additional challenges for sustainable fisheries management., Competing Interests: None declared., (© 2022 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd.)

Gene flow shapes spatial genetic structure and the potential for local adaptation. Among marine animals with nonmigratory adults, the presence or absence of a pelagic larval stage is thought to be a key determinant in shaping gene flow and the genetic structure of populations. In addition, the spatial distribution of suitable habitats is expected to influence the distribution of biological populations and their connectivity patterns. We used whole genome sequencing to study demographic history and reduced representation (double-digest restriction associated DNA) sequencing data to analyse spatial genetic structure in broadnosed pipefish (Syngnathus typhle). Its main habitat is eelgrass beds, which are patchily distributed along the study area in southern Norway. Demographic connectivity among populations was inferred from long-term (~30-year) population counts that uncovered a rapid decline in spatial correlations in abundance with distance as short as ~2 km. These findings were contrasted with data for two other fish species that have a pelagic larval stage (corkwing wrasse, Symphodus melops; black goby, Gobius niger). For these latter species, we found wider spatial scales of connectivity and weaker genetic isolation-by-distance patterns, except where both species experienced a strong barrier to gene flow, seemingly due to lack of suitable habitat. Our findings verify expectations that a fragmented habitat and absence of a pelagic larval stage promote genetic structure, while presence of a pelagic larvae stage increases demographic connectivity and gene flow, except perhaps over extensive habitat gaps., (© 2022 The Authors. Molecular Ecology published by John Wiley & Sons Ltd.)

The European Commission asked EFSA to deliver an opinion on the nutritional safety and suitability of a specific protein hydrolysate. It is derived from whey protein concentrate and used in infant and follow-on formula by HIPP-Werk Georg Hipp OHG. The dossier that was submitted to the European Commission aimed at requesting an amendment of Regulation (EU) 2016/127 with respect to the protein sources that may be used in infant and/or follow-on formula. This opinion does not cover the assessment of the safety of the food enzymes used in the manufacture of the protein hydrolysate. The protein hydrolysate under evaluation is sufficiently characterised with respect to the fraction of the hydrolysed protein. In the pertinent intervention study provided, an infant formula manufactured from the protein hydrolysate with a protein content of 1.9 g/100 kcal and consumed as the sole source of nutrition by infants for 3 months led to growth equivalent to a formula manufactured from intact cow's milk protein with the same protein content. No experimental data have been provided on the nutritional safety and suitability of this protein source in follow-on formula. However, given that it is consumed with complementary foods and the protein source is considered nutritionally safe and suitable in an infant formula that is the sole source of nutrition of infants, the Panel considers that the protein hydrolysate is also a nutritionally safe and suitable protein source for use in follow-on formula. The Panel concludes that the protein hydrolysate under evaluation is a nutritionally safe and suitable protein source for use in infant and follow-on formula, as long as the formula in which it is used contains a minimum of 1.9 g/100 kcal protein and complies with the compositional criteria of Commission Delegated Regulation (EU) 2016/127 and the amino acid pattern in its Annex IIIA., (© 2022 Wiley‐VCH Verlag GmbH & Co. KgaA on behalf of the European Food Safety Authority.)

Life on Earth has been characterized by recurring cycles of ecological stasis and disruption, relating biological eras to geological and climatic transitions through the history of our planet. Due to the increasing degree of ecological abruption caused by human influences many advocate that we now have entered the geological era of the Anthropocene, or "the age of man." Considering the ongoing mass extinction and ecosystem reshuffling observed worldwide, a better understanding of the drivers of ecological stasis will be a requisite for identifying routes of intervention and mitigation. Ecosystem stability may rely on one or a few keystone species, and the loss of such species could potentially have detrimental effects. The Atlantic cod ( Gadus morhua ) has historically been highly abundant and is considered a keystone species in ecosystems of the northern Atlantic Ocean. Collapses of cod stocks have been observed on both sides of the Atlantic and reported to have detrimental effects that include vast ecosystem reshuffling. By whole-genome resequencing we demonstrate that stabilizing selection maintains three extensive "supergenes" in Atlantic cod, linking these genes to species persistence and ecological stasis. Genomic inference of historic effective population sizes shows continued declines for cod in the North Sea-Skagerrak-Kattegat system through the past millennia, consistent with an early onset of the marine Anthropocene through industrialization and commercialization of fisheries throughout the medieval period., Competing Interests: The authors declare no competing interest., (Copyright © 2022 the Author(s). Published by PNAS.)

In situ soil washing at the field scale has not yet been investigated as a remediation strategy for soils impacted by per- and polyfluoroalkyl substances (PFAS). This remediation strategy is a promising low-cost alternative to other costlier remediation options like excavating, transporting and landfilling large amounts of PFAS contaminated soil. However, it is unclear if it is effective at the field scale, where large areas of heterogenous soil can be challenging to saturate with infiltration water and then pump to a treatment facility. To address this for the first time, herein we established three different trials involving in situ washing of an undisturbed, 3 m deep, sandy vadose zone soil contaminated with aqueous film forming foam (AFFF). The trials were performed at a site with an established pump and treat system for treating PFAS contaminated groundwater. In situ soil washing was compared to the more conventional practice of washing excavated soil on top of an impermeable bottom lining where the PFAS contaminated water was collected and monitored in a drainage system before treatment. The measured amount of perfluorooctane sulfonate (PFOS) removed was compared with expectations based on a non-calibrated, 1-D first order rate saturated soil model using only the local soil-to-water distribution coefficient as well as the volume and irrigation rate of wash water as input. This model predicted results within a factor of 2. The suspected reasons for small discrepancies between model predictions and excavated vs in situ washing was a combination of the heterogeneity of PFOS distribution in the soil as well as preferential flow paths during soil washing that prevented full saturation. This analysis showed that in situ soil washing was more efficient and less costly than washing excavated sandy soil, particularly if a pump-and-treat system is already in place., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Coexistence of ecotypes, genetically divergent population units, is a widespread phenomenon, potentially affecting ecosystem functioning and local food web stability. In coastal Skagerrak, Atlantic cod ( Gadus morhua ) occur as two such coexisting ecotypes. We applied a combination of acoustic telemetry, genotyping, and stable isotope analysis to 72 individuals to investigate movement ecology and food niche of putative local "Fjord" and putative oceanic "North Sea" ecotypes-thus named based on previous molecular studies. Genotyping and individual origin assignment suggested 41 individuals were Fjord and 31 were North Sea ecotypes. Both ecotypes were found throughout the fjord. Seven percent of Fjord ecotype individuals left the study system during the study while 42% of North Sea individuals left, potentially homing to natal spawning grounds. Home range sizes were similar for the two ecotypes but highly variable among individuals. Fjord ecotype cod had significantly higher δ 13 C and δ 15 N stable isotope values than North Sea ecotype cod, suggesting they exploited different food niches. The results suggest coexisting ecotypes may possess innate differences in feeding and movement ecologies and may thus fill different functional roles in marine ecosystems. This highlights the importance of conserving interconnected populations to ensure stable ecosystem functioning and food web structures., Competing Interests: All authors declare to have no conflicts of interest., (© 2021 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Marine reserves can protect fish populations by increasing abundance and body size, but less is known about the effect of protection on fish behaviour. We looked for individual consistency in movement behaviours of sea trout in the marine habitat using acoustic telemetry to investigate whether they represent personality traits and if so, do they affect survival in relation to protection offered by a marine reserve. Home range size had a repeatability of 0.21, suggesting that it represents a personality trait, while mean swimming depth, activity and diurnal vertical migration were not repeatable movement behaviours. The effect of home range size on survival differed depending on the proportion of time fish spent in the reserve, where individuals spending more time in the reserve experienced a decrease in survival with larger home ranges while individuals spending little time in the reserve experienced an increase in survival with larger home ranges. We suggest that the diversity of fish home range sizes could be preserved by establishing networks of marine reserves encompassing different habitat types, ensuring both a heterogeneity in environmental conditions and fishing pressure., Competing Interests: None declared., (© 2021 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd.)

Translocation and introduction of non-native organisms can have major impacts on local populations and ecosystems. Nevertheless, translocations are common practices in agri- and aquaculture. Each year, millions of wild-caught wrasses are transported large distances to be used as cleaner fish for parasite control in marine salmon farms. Recently, it was documented that translocated cleaner fish are able to escape and reproduce with local wild populations. This is especially a challenge in Norway, which is the world's largest salmon producer. Here, a panel of 84 informative SNPs was developed to identify the presence of nonlocal corkwing wrasse ( Symphodus melops ) escapees and admixed individuals in wild populations in western Norway. Applying this panel to ~2000 individuals, escapees and hybrids were found to constitute up to 20% of the local population at the northern edge of the species' distribution. The introduction of southern genetic material at the northern edge of the species distribution range has altered the local genetic composition and could obstruct local adaptation and further range expansion. Surprisingly, in other parts of the species distribution where salmon farming is also common, few escapees and hybrids were found. Why hybridization seems to be common only in the far north is discussed in the context of demographic and transport history. However, the current lack of reporting of escapes makes it difficult to evaluate possible causes for why some aquaculture-dense areas have more escapees and hybrids than others. The results obtained in this study, and the observed high genomic divergence between the main export and import regions, puts the sustainability of mass translocation of nonlocal wild wrasse into question and suggests that the current management regime needs re-evaluation., Competing Interests: None declared., (© 2021 The Authors. Evolutionary Applications published by John Wiley & Sons Ltd.)

Chemical contaminants are present in all foods. Data on the occurrence of contaminants in foods that are often consumed or contain high contaminant concentrations are critical for the estimation of exposure and evaluation of potential negative health effects. Due to limited resources for the monitoring of contaminants and other chemical substances in foods, methods for prioritisation are needed. We have developed a straightforward semi-quantitative method to rank chemical substances in foods for monitoring as part of a risk-based food control. The method is based on considerations of toxicity, level of exposure including both occurrence in food and dietary intake, vulnerability of one or more population groups due to high exposure because of special food habits or resulting from specific genetic variants, diseases, drug use or age/life stages, and the adequacy of both toxicity and exposure data. The chemical substances ranked for monitoring were contaminants occurring naturally, unintentionally or incidentally in foods or formed during food processing, and the inclusion criteria were high toxicity, high exposure and/or lack of toxicity or exposure data. In principle, this method can be used for all classes of chemical substances that occur in foods, both unintended contaminants and deliberately added chemical substances. Foods considered relevant for monitoring of the different chemical substances were also identified. The outcomes of ranking exercises using the new method including considerations of vulnerable groups and adequacy of data and a shortened version based on risk considerations only were compared. The results showed that the resolution between the contaminants was notably increased with the extended method, which we considered as advantageous for the ranking of chemical substances for monitoring in foods., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Sediment samples (0-1 cm) and tube-dwelling polychaetes from the Norwegian Continental Shelf and the Barents Sea were collected, including areas close to oil and gas installations and remote locations. Microplastics (≥45 μm) were found in quantifiable levels in 27 of 35 sediment samples, from 0.039 to 3.4 particles/g dw (dw = dry weight); and in 9 of 10 pooled polychaete samples, from 11 to 880 particles/g ww (ww = wet weight). Concentrations were significantly higher in tube-dwelling polychaetes than sediments from the same locations (p<0.0097) by orders of magnitude. To quantify this factor increase in polychaetes, a Biota-Sediment Particle Enrichment Factor (BSPEF) is introduced, which ranged from 100 to 11000 g dw /g ww (280-31000 g dw /g dw ). Higher microplastic levels were observed in polychaete tube than in soft tissue (n=4). The feeding behavior and life cycle of tube-dwelling polychaetes could have an important influence on the transport, distribution and food-chain dynamics of microplastics on the seafloor., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Identifying and quantifying microplastic in marine samples can be facilitated by removing natural organic matter (NOM). Cellulosic material, like chitin, however, are a type of NOM that is resistant to chemical digestion, and difficult to eliminate from samples. To address this, a two-step digestion method was developed to remove or reduce cellulosic materials in diverse marine media. This method was applied to reference microplastics, reference cellulosic materials, and diverse marine samples from the Inner Oslofjord Norway. This included plankton, seabed sediments near a water treatment plant and driftline sand. The method was developed and tested for plastic particles >45 μm. The first-step was to pre-dissolve cellulosic materials using a mixture of urea:thiourea:NaOH. This was followed by an oxidative digestion step, here using H 2 O 2 and NaOH. Most reference plastics were unaffected, except minor effects for PET and nylon. After sufficient repetitions, cellulosic materials in both reference and marine samples were largely removed. This method was compared to other digestion methods used for microplastic quantification, including single-step oxidation, alkaline treatment, acid treatment and enzymatic treatment. The results indicate that the pre-dissolution step greatly facilitates NOM and cellulosic material digestion for the purpose of microplastic quantification., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Capture and long-distance translocation of cleaner fish to control lice infestations on marine salmonid farms has the potential to influence wild populations via overexploitation in source regions, and introgression in recipient regions. Knowledge of population genetic structure is therefore required. We studied the genetic structure of ballan wrasse, a phenotypically diverse and extensively used cleaner fish, from 18 locations in Norway and Sweden, and from Galicia, Spain, using 82 SNP markers. We detected two very distinct genetic groups in Scandinavia, northwestern and southeastern. These groups were split by a stretch of sandy beaches in southwest Norway, representing a habitat discontinuity for this rocky shore associated benthic egg-laying species. Wrasse from Galicia were highly differentiated from all Scandinavian locations, but more similar to northwestern than southeastern locations. Distinct genetic differences were observed between sympatric spotty and plain phenotypes in Galicia, but not in Scandinavia. The mechanisms underlying the geographic patterns between phenotypes are discussed, but not identified. We conclude that extensive aquaculture-mediated translocation of ballan wrasse from Sweden and southern Norway to western and middle Norway has the potential to mix genetically distinct populations. These results question the sustainability of the current cleaner fish practice., Competing Interests: None declared., (© 2020 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Understanding the biological processes involved in genetic differentiation and divergence between populations within species is a pivotal aim in evolutionary biology. One particular phenomenon that requires clarification is the maintenance of genetic barriers despite the high potential for gene flow in the marine environment. Such patterns have been attributed to limited dispersal or local adaptation, and to a lesser extent to the demographic history of the species. The corkwing wrasse (Symphodus melops) is an example of a marine fish species where regions of particular strong divergence are observed. One such genetic break occurred at a surprisingly small spatial scale (F ST ~0.1), over a short coastline (<60 km) in the North Sea-Skagerrak transition area in southwestern Norway. Here, we investigate the observed divergence and purported reproductive isolation using genome resequencing. Our results suggest that historical events during the post-glacial recolonization route can explain the present population structure of the corkwing wrasse in the northeast Atlantic. While the divergence across the break is strong, we detected ongoing gene flow between populations over the break suggesting recent contact or negative selection against hybrids. Moreover, we found few outlier loci and no clear genomic regions potentially being under selection. We concluded that neutral processes and random genetic drift e.g., due to founder events during colonization have shaped the population structure in this species in Northern Europe. Our findings underline the need to take into account the demographic process in studies of divergence processes., (© 2019 The Authors. Molecular Ecology published by John Wiley & Sons Ltd.)