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Whole-ocean network design and implementation pathway for Arctic marine conservation
Get PDFForestalling the decline of global biodiversity requires urgent and transformative action at all levels of government and society, particularly in the Arctic Ocean and adjacent seas where rapid changes are already underway. Amid growing scientific support and mounting pressure, the majority of nations have committed to the most ambitious conservation targets yet. However, without an approach that inclusively and equitably reconciles conservation and sustainable ocean use, these targets will likely go unmet. Here, we present ArcNet: a network design framework to help achieve ocean-scale, area-based marine conservation in the Arctic. The framework is centred around a suite of web-based tools and a ~ 5.9 million km2 network of 83 priority areas for conservation designed through expert-driven systematic conservation planning using conservation targets for over 800 features representing Arctic biodiversity. The ArcNet framework is intended to help adapt to new and emerging information, foster collaboration, and identify tailored conservation measures within a global context at different levels of planning and implementation.publishedVersio
Modellert påvirkning av lakselus på vill laksefisk i 2024
Get PDFI denne rapporten presenteres Havforskningsinstituttets modellprodukter til Trafikklysvurderingen; modellert smittepress og påslag av lus på utvandrende postsmolt langs hele norskekysten. Modellproduktene er ment å bli vurdert sammen med observasjoner, og utfyller disse ved å gi viktig tilleggsinformasjon ettersom modellene spenner over større områder, og over lengre tid enn det er praktisk mulig å observere. Rapporten omfatter hovedsakelig resultater for 2024. Modellproduktene inngår i Havforskningsinstituttets bidrag til ekspertgruppen for Trafikklyssystemet og grunnlaget for vurderingen av lakselus-indusert dødelighet per produksjonsområde.Modellert påvirkning av lakselus på vill laksefisk i 2024publishedVersio
Tolerance to fluctuating currents in farmed Atlantic salmon: a novel method to simulate offshore wave effects in the laboratory
Get PDFTo ensure acceptable animal welfare in emerging offshore Atlantic salmon aquaculture, it is crucial to understand the biological limits of the fish. Much work has been done on the effects of water currents, but few studies exist on waves, owing to logistical limitations. The purpose of this study was therefore to establish a method to replicate wave-like fluctuating water currents in the laboratory and quantify tolerance limits in salmon. To accomplish this, a swim tunnel system was modified so that current speeds could be programmed to automatically alternate between minimum and peak speeds of a desired magnitude and interval. The critical swimming speed (Ucrit) was subsequently measured in salmon of ~800 g as a baseline from which standardized tests of fluctuating currents could be prescribed. Fluctuating current trials were then performed using minimum speeds of 20% Ucrit and peak speeds of 80, 100, 120, and 140% Ucrit, and cycles of 0.5, 1, and 2 min. Fish were tested for 4 h or until they fatigued. All fish at 80 and 100% Ucrit endured 4 h of fluctuating currents. However, at 120% Ucrit, only 17% completed the test, and at 140% Ucrit, all fish became fatigued within 1.5 h, thus defining acute limits to fluctuating peak speeds. Wave interval did not affect fatigue times significantly. In conclusion, a novel method is introduced here to assess tolerances to various wave-like environments, showing that salmon can endure ~20% higher peak speeds in dynamic fluctuating currents when compared to known swimming capacities at constant speeds.publishedVersio
Low uptake of pharmaceuticals in edible mushrooms grown in polluted biogas digestate
Get PDFThe uptake dynamics of two sulfonamide antibiotics, two fluoroquinolone antibiotics, and the anticonvulsant carbamazepine during the cultivation of two species of edible mushrooms (Agaricus subrufescens and A. bisporus) was investigated. None of the antibiotics were accumulated by the mushrooms, while carbamazepine and its transformation product carbamazepine-10,11-epoxide were taken up by A. bisporus fruiting body but only in small amounts (up to 0.76 and 1.85 μg kg−1 dry weight, respectively). The sulfonamides were quickly removed from the mushroom growth substrate, while the recalcitrant fluoroquinolones and carbamazepine were only partially removed. Dissipation half-lives were generally lower for A. subrufescens than A. bisporus, but A. subrufescens was also grown at a slightly higher culture temperature. A. subrufescens also showed a lower uptake of contaminants. Comparison of maximum dietary intake with other common exposure sources showed that these mushrooms can safely be eaten although produced on a polluted substrate, with respect to the investigated compounds.publishedVersio
Genetic monitoring uncovers long-distance marine feeding coupled with strong spatial segregation in sea trout (Salmo trutta L.) consistent at annual and decadal time scales
Get PDFGenetic data have greatly increased means to understand fish marine migration behaviours at large spatial scale within a quantitative framework. The anadromous sea trout is a prized target of recreational fishery and an important ecosystem component in freshwater and marine coastal habitats in large parts of temperate northern Europe. Nonetheless, little is known about population distributions while feeding at sea. To reconcile notions about feeding migrations being predominantly locally restricted or not, we used SNP data for 3465 trout representing >100 rivers to identify population origins of 903 coastally feeding fish captured throughout the North Sea-Baltic Sea transition area. Across areas, coastal collections generally showed marked stock-mixing and overall 70:30% native:non-native fish with seasonal variation corresponding with spawning run timing. Data revealed strong spatial feeding segregation between trout from the Scandinavian Peninsula and the European continent. This is surprising given the short distances between areas, but is in alignment with strong genetic differentiation between populations in these areas. Estimation of stock complexity of coastal feeding aggregations showed no spatial trend through the North Sea-Baltic Sea transition area otherwise characterized by strong environmental clines. Analyses of scale samples collected in the 1950s indicate that stock-mixing was consistent over almost 70 years.publishedVersio
Råd om fiske av snøkrabbe på norsk sokkel i Barentshavet 2025
Get PDFBasert på MSY-tilnærmingen anbefaler Havforskningsinstituttet at totalfangsten av snøkrabbe på norsk sokkel i 2025 ikke bør overstige 12 724 tonn.Råd om fiske av snøkrabbe på norsk sokkel i Barentshavet 2025publishedVersio
Size-fractioned zooplankton biomass in the Barents Sea ecosystem: changes during four decades of warming and four capelin collapses (1980-2020)
Get PDFZooplankton in the Barents Sea has been monitored by the Institute of Marine Research in Norway on autumn cruises since 1986, using a standardized procedure with determination of dry weight biomass in three size fractions following splitting of the sample in two halves. Along with summer data for the early 1980s, we can now describe changes of zooplankton biomass over four decades. The biomass of the central Barents Sea has fluctuated inversely with collapses and recoveries of the Barents Sea capelin stock, which is a major planktivore. Zooplankton biomass in the central Barents Sea was low in 1983 and 1984, driven by low abundance of Calanus finmarchicus, followed by a pronounced peak in 1987 associated with a “first” collapse of the capelin stock. Biomass showed another pronounced peak in 1994, driven by the small size fraction and interpreted to reflect an advective signal from the adjacent Norwegian Sea. In the two most recent decades, there have been divergent trends, with a relatively high biomass in the inflowing Atlantic water, reflecting a second summer generation of C. finmarchicus, and decreased biomass in the central area, reflecting a lower abundance of Calanus glacialis driven by a combined effect of capelin predation and climate.publishedVersio
Risiko knyttet til gyting i merd hos oppdrettstorsk ulike deler av året
Get PDFEn gjennomgang av kunnskapen knyttet til gyting i merd hos oppdrettstorsk viser at temperatur er en sentral faktor for å kunne vurdere miljørisiko. Atlantisk torsk er utbredt på begge sider av Atlanterhavet, og innenfor utbredelsesområdet er hovedregelen gyting om våren. Men det forekommer også populasjoner med gyting på andre årstider som omfatter de fleste av årets måneder. Langs norskekysten er sommer- og høstgyting blant villtorsk ikke verifisert, men i Vest-Finnmark er det påvist skrei med moden rogn så seint som månedsskiftet mai-juni. Eksperimentelle forsøk har vist at de fysiologiske prosessene som leder til god eggmodning og normal eggutvikling hos torsk blir negativt påvirket ved temperaturer fra ca. 10 °C og høyere, mens torskelarver har en større toleranse for slike temperaturer og kan vokse godt ved 17 °C i de mer utviklede larvestadiene. Ved kjønnsmodning og gyting i temperaturer over 10 °C har forsøk imidlertid vist at en liten andel egg vil befruktes, og en god del av disse vil ha en normal utvikling i det første eggstadiet. I et tilfelle med omfattende kjønnsmodning i et oppdrettsanlegg og påfølgende gyting i merd under slike temperaturforhold kan det derfor tenkes å være en betydelig mengde befruktede egg i god utvikling. Data for årstidsvariasjoner i temperatur har ikke vært tilgjengelig for de syv lokalitetene det ønskes en vurdering for, og simulerte data fra en hydrodynamisk modell har derfor blitt benyttet. Simuleringene viser en betydelig variasjon mellom år og innen en måned, og data om faktiske temperaturforhold bør benyttes som et tillegg i en vurdering om kjønnsmodning i et anlegg har behov for oppfølging utenom normal gytesesong. Data på forekomst av dyreplankton viser at byttedyr for torskelarver vil være til stede langs norskekysten utenom normal gytesesong, både sommer og høst.Risiko knyttet til gyting i merd hos oppdrettstorsk ulike deler av åretpublishedVersio
Effects of the sea lice chemotherapeutant, emamectin benzoate, on metabolism and behaviour of the sea-pen Pennatula phosphorea
Get PDFChemotherapeutants used to control infestations by sea lice can be released into the marine environment surrounding aquaculture farms. Among these therapeutic agents, emamectin benzoate is extensively utilized even though its impact on non-target taxa has not been thoroughly examined. In this context, we explored the effects of emamectin benzoate on a common Norwegian habitat-forming species: the phosphorescent sea-pen Pennatula phosphorea. Specifically, we examined P. phosphorea metabolic and responses before, during and after exposure to emamectin benzoate. Results indicate that an 8-day emamectin benzoate exposure (0.8 mg/L) did not induce P. phosphorea mortality or significant behavioural or metabolic modifications. However, we highlighted the presence and persistence of emamectin benzoate in exposed P. phosphorea tissue. These results indicate that emamectin benzoate is unlikely to adversely impact P. phosphorea populations in the environment. However, persistence of emamectin benzoate in tissue constitutes a potential for bioaccumulation with repeated treatments and should be examined in further studies.publishedVersio
The effect of enzymatic and viability dye treatment in combination with long-range PCR on assessing Tulane virus infectivity
Get PDFHuman norovirus (HuNoV) is regularly involved in food-borne infections. To detect infectious HuNoV in food, RT-qPCR remains state of the art but also amplifies non-infectious virus. The present study combines pre-treatments, RNase and propidium monoazide, with three molecular analyses, including long-range PCR, to predominantly detect infectious Tulane virus (TuV), a culturable HuNoV surrogate. TuV was exposed to inactivating conditions to assess which molecular method most closely approximates the reduction in infectious virus determined by cell culture (TCID50). After thermal treatments (56 °C/5 min, 70 °C/5 min, 72 °C/20 min), TCID50 reductions of 0.3, 4.4 and 5.9 log10 were observed. UV exposure (40/100/1000 mJ/cm2) resulted in 1.1, 2.5 and 5.9 log10 reductions. Chlorine (45/100 mg/L for 1 h) reduced infectious TuV by 2.0 and 3.0 log10. After thermal inactivation standard RT-qPCR, especially with pre-treatments, showed the smallest deviation from TCID50. On average, RT-qPCR with pre-treatments deviated by 1.1–1.3 log10 from TCID50. For UV light, long-range PCR was closest to TCID50 results. Long-range reductions deviated from TCID50 by ≤0.1 log10 for mild and medium UV-conditions. However, long-range analyses often resulted in qPCR non-detects. At higher UV doses, RT-qPCR with pre-treatments differed by ≤1.0 log10 from TCID50. After chlorination the molecular methods repeatedly deviated from TCID50 by >1.0 log10, Overall, each method needs to be further optimized for the individual types of inactivation treatment.publishedVersio