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Monitoring litter on Arctic and subarctic shorelines: current status and next steps for monitoring programs
Get PDFPlastic pollution is ubiquitous, and the Arctic is no exception. One important step to understand the extent of the problem, and to monitor its impact is to have repeatable, comparable, and relevant measures across time and space that allow for the detection of marine litter trends. Arctic shorelines are a critical part of monitoring efforts. Pan-Arctic monitoring of litter on shorelines is also an essential component to examine global trends. Based on previous work examining litter in some regions of the Arctic, we suggest steps towards more harmonized protocols that include community-based monitoring, crowdsourced science programs, and science team-based surveys that are specific for the Arctic. Specifically, we recommend that shoreline survey sites for long-term monitoring be established where possible and be at least 50 m and surveys carried out at regular intervals of at least twice a year by any type of research team. Criteria for the selection of sites should be grounded in Indigenous and other local community and regional priorities, and should result in representation of both remote shorelines impacted by distant-source marine litter and shorelines impacted by more local sources. Results of any Arctic shoreline litter surveys should be made regularly available either through publications which include data sets, and/or accessible databases to promote regional comparisons and trend analysis across the pan-Arctic.publishedVersio
Lakselusinfestasjon på vill laksefisk våren 2023 — Fremdriftsrapport til Mattilsynet
Get PDFOvervåkingsprogrammet for lakselus på vill laksefisk (NALO) gjennomføres på oppdrag fra Mattilsynet og Nærings og Fiskeridepartementet, og har som mål å skaffe robuste data på lakselusinfestasjon hos vill laksefisk i alle 13 produksjonsområder for akvakultur. Fjordene hvor infestasjonen av lakselus er undersøkt på trålfanget postsmolt av laks er noe endret fra tidligere, Trondheimsfjorden og Altafjorden blir ikke undersøkt, i stedet blir Nordfjord og Vågsfjord (sør for Senja) undersøkt. Sjøørretstasjonene er omtrent som i fjor. Feltundersøkelsen i NALO gjennomføres fra slutten av april til siste uken i juli. I denne framdriftsrapporten presenteres foreløpige lusedata på laks og sjøørret fra Sørlandet til Trøndelag.Lakselusinfestasjon på vill laksefisk våren 2023 — Fremdriftsrapport til MattilsynetpublishedVersio
Protected fish spawning aggregations as self-replenishing reservoirs for regional recovery
Get PDFDispersal of eggs and larvae from spawning sites is critical to the population dynamics and conservation of marine fishes. For overfished species like critically endangered Nassau grouper (Epinephelus striatus), recovery depends on the fate of eggs spawned at the few remaining aggregation sites. Biophysical models can predict larval dispersal, yet these rely on assumed values of key parameters, such as diffusion and mortality rates, which have historically been difficult or impossible to estimate. We used in situ imaging to record three-dimensional positions of individual eggs and larvae in proximity to oceanographic drifters released into egg plumes from the largest known Nassau grouper spawning aggregation. We then estimated a diffusion–mortality model and applied it to previous years' drifter tracks to evaluate the possibility of retention versus export to nearby sites within 5 days of spawning. Results indicate that larvae were retained locally in 2011 and 2017, with 2011 recruitment being a substantial driver of population recovery on Little Cayman. Export to a nearby island with a depleted population occurred in 2016. After two decades of protection, the population appears to be self-replenishing but also capable of seeding recruitment in the region, supporting calls to incorporate spawning aggregation protections into fisheries management.publishedVersio
Behaviour and habitat use of first-time migrant Arctic charr: novel insights from a subarctic marine area
Get PDFAnadromous Arctic charr Salvelinus alpinus is a cold-adapted salmonid that is vulnerable to climate warming and anthropogenic activities including salmon farming, hydropower regulation, and pollution, which poses a multiple-stressor scenario that influences or threatens populations. We studied the horizontal and vertical behaviour of Arctic charr tagged with acoustic transmitters (n = 45, mean fish length: 22 cm) in a pristine, subarctic marine area to provide insights into the behaviour of first-time migrants. Tagged fish spent up to 78 d at sea, with high marine survival (82% returned to their native watercourse). While at sea, they utilized mostly near-shore areas, up to 45 km away from their native river. Arctic charr showed large variation in migration distance (mean ± SD: 222 ± 174 km), and the migration distance increased with body size. Although the fish displayed a strong fidelity to surface waters (0-3 m), spatiotemporal variation in depth use was evident, with fish utilizing deeper depths during the day and in late July. These results represent baseline data on Arctic charr’s marine behaviour in a pristine fjord system and highlight the importance of near-shore surface water as feeding areas for first-time migrants. Furthermore, the observed dependency on coastal areas implies a vulnerability to increasing human-induced perturbations, on top of impacts by large-scale climate change in marine and freshwater habitats.publishedVersio
Ecosystem response to darkening of the coastal zone – food web implications - Pilot Study
Get PDFThe Ecosystem response to darkening of the coastal zone – food web implications project was financed as pilot study within the to acquire preliminary knowledge on how the coastal ¨darkening¨ phenomenon affects plankton composition, distribution, and dynamics. The data collected provide base knowledge for future research focusing on the effects of increased river runoff due to changing climate on the flow of energy and carbon within the lower food web and ultimately, the potential repercussions on fish recruitment.Ecosystem response to darkening of the coastal zone – food web implications - Pilot StudypublishedVersio
Panel-based Assessment of Ecosystem Condition of the Norwegian Sea Pelagic Ecosystem
Get PDFThe System for Assessment of Ecological Condition, coordinated by the Norwegian Environment Agency, is intended to form the foundation for evidence-based assessments of the ecological condition of Norwegian terrestrial and marine ecosystems not covered by the EU Water Framework Directive. The reference condition is defined as “intact ecosystems”, i.e., a condition that is largely unimpacted by modern industrial activities. An ecosystem in good ecological condition does not deviate substantially from this reference condition in structure, functions or productivity. This report describes the first operational assessment of the ecological condition of the pelagic ecosystem in the Norwegian Sea. The assessment method employed is the Panel-based Assessment of Ecosystem Condition (PAEC1) and the current assessment has considered to what extent the Norwegian Sea pelagic ecosystem deviates from the reference condition2 by evaluating change in trajectories.Panel-based Assessment of Ecosystem Condition of the Norwegian Sea Pelagic EcosystempublishedVersio
Monitoring programme for veterinary control on seafood products imported to Norway from third countries - Results from 2022
Get PDFThis report summarises results from the ongoing monitoring programme for veterinary border control on seafood products imported to Norway from countries outside the EU and the European Economic Area in 2022. Eight samples of products imported in 2021 but analysed in 2022 are also included. Samples were collected by personnel at the Norwegian Border Inspection Posts (BIP). The Institute of Marine Research (IMR) carried out the analytical work on behalf of the Norwegian Food Safety Authority (NFSA). We want to thank NFSA for good cooperation during the conduct of this monitoring programme. A risk assessment for different groups of imported products formed the basis for the selection of analytical activities, where current trend of hazards, as reported in The Rapid Alert System for Food and Feed (RASFF) notification system and the compositional nature of the products and origin formed an up-to-date basis for the risk assessment.Monitoring programme for veterinary control on seafood products imported to Norway from third countries - Results from 2022publishedVersio
Atlantic cod individual spatial behaviour and stable isotope associations in a no-take marine reserve
Get PDFForaging is a behavioural process and, therefore, individual behaviour and diet are theorized to covary. However, few comparisons of individual behaviour type and diet exist in the wild. We tested whether behaviour type and diet covary in a protected population of Atlantic cod, Gadus morhua. Working in a no-take marine reserve, we could collect data on natural behavioural variation and diet choice with minimal anthropogenic disturbance. We inferred behaviour using acoustic telemetry and diet from stable isotope compositions (expressed as δ13C and δ15N values). We further investigated whether behaviour and diet could have survival costs. We found cod with shorter diel vertical migration distances fed at higher trophic levels. Cod δ13C and δ15N values scaled positively with body size. Neither behaviour nor diet predicted survival, indicating phenotypic diversity is maintained without survival costs for cod in a protected ecosystem. The links between diet and diel vertical migration highlight that future work is needed to understand whether the shifts in this behaviour during environmental change (e.g. fishing or climate), could lead to trophic cascades.publishedVersio
Monitoring programme for veterinary control on seafood products imported to Norway from third countries - Results from 2021
Get PDFThis report summarises results from the ongoing monitoring programme for veterinary border control on seafood products imported to Norway from countries outside the EU and the European Economic Area in 2021.Monitoring programme for veterinary control on seafood products imported to Norway from third countries - Results from 2021publishedVersio