Halvor Knutsen

• Gustafsson, Malin; Strand, Åsa; Laugen, Ane Timenes; Albretsen, Jon; André, Carl & Broström, Göran [Show all 13 contributors for this article] (2024). Unlocking the secret life of blue mussels: Exploring connectivity in the Skagerrak through biophysical modeling and population genomics. Evolutionary Applications. ISSN 1752-4571. 17(5), p. 1–18. doi: 10.1111/eva.13704.
• Norderhaug, Kjell Magnus; Knutsen, Halvor; Filbee-Dexter, Karen; Sodeland, Marte; Jorde, Per Erik & Wernberg, Thomas [Show all 8 contributors for this article] (2024). The International Union for Conservation of Nature Red List does not account for intraspecific diversity. ICES Journal of Marine Science. ISSN 1054-3139. doi: 10.1093/icesjms/fsae039.
• Synnes, Ann-Elin; Olsen, Esben Moland; Jorde, Per Erik; Knutsen, Halvor & Moland, Even (2023). Contrasting management regimes indicative of mesopredator release in temperate coastal fish assemblages. Ecology and Evolution. ISSN 2045-7758. 13(12). doi: 10.1002/ece3.10745. Full text in Research Archive Show summary

  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.

• Jansson, Eeva; André, Carl; Quintela, Maria; Halvorsen, Kim Aleksander Tallaksen; Besnier, Francois & Ayllon, Fernando [Show all 10 contributors for this article] (2023). Genetic study reveals local differentiation persisting in the face of high connectivity and a genomic inversion likely linked with sexual antagonism in a common marine fish. ICES Journal of Marine Science. ISSN 1054-3139. 80(4), p. 1103–1112. doi: 10.1093/icesjms/fsad042. Full text in Research Archive
• McGill, L.; McDevitt, A.D.; Hellemans, B.; Neat, F.; Knutsen, Halvor & Mariani, S. [Show all 10 contributors for this article] (2023). Population structure and connectivity in the genus Molva in the Northeast Atlantic. ICES Journal of Marine Science. ISSN 1054-3139. 80(4), p. 1079–1086. doi: 10.1093/icesjms/fsad040. Full text in Research Archive Show summary

  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.

• Helmerson, Cecilia; Weist, Peggy; Brieuc, Marine Servane Ono; Maurstad, Marius Filomeno; Schade, Franziska Maria & Dierking, Jan [Show all 14 contributors for this article] (2023). Evidence of hybridization between genetically distinct Baltic cod stocks during peak population abundance(s). Evolutionary Applications. ISSN 1752-4571. 16(7), p. 1359–1376. doi: 10.1111/eva.13575. Full text in Research Archive Show summary

  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.

• Henriksson, Simon; Pereyra, Ricardo; Sodeland, Marte; Ortega-Martinez, Olga; Knutsen, Halvor & Wennhage, Håkan [Show all 7 contributors for this article] (2022). Mixed origin of juvenile Atlantic cod (Gadus morhua) along the Swedish west coast. ICES Journal of Marine Science. ISSN 1054-3139. doi: 10.1093/icesjms/fsac220. Full text in Research Archive Show summary

  Cryptic population structure in exploited fishes poses a major challenge for fisheries management. In Atlantic cod, sympatric ecotypes are well-known, for instance off the coast of northern Norway. Recently, two sympatric cod ecotypes have also been documented in the Skagerrak and Kattegat, where adult cod has declined dramatically. One ecotype has an apparent offshore origin and displays a more migratory lifestyle than the other, which is generally resident at the coast throughout its life. To investigate their relative abundances along the Swedish west coast, juvenile cod were collected at high spatial resolution along the coast and genetically assigned to ecotypes. The results reveal large proportions of the coastal ecotype in the southern Kattegat, Öresund, and inshore Swedish Skagerrak, whereas the offshore ecotype dominates in offshore areas. A regression model comparison suggests that differences in bottom depth, rather than distance from the open sea, explain the heterogeneous spatial distribution of the two ecotypes. In addition, the two ecotypes display genetic differences suggesting adaptation to different environments. The results underline that successful fisheries management requires identification and consideration of locally adapted sympatric ecotypes.

• Oomen, Rebekah Alice; Knutsen, Halvor; Olsen, Esben Moland; Jentoft, Sissel; Stenseth, Nils Christian & Hutchings, Jeffrey (2022). Warming Accelerates the Onset of the Molecular Stress Response and Increases Mortality of Larval Atlantic Cod. Integrative and Comparative Biology. ISSN 1540-7063. 62(6), p. 1784–1801. doi: 10.1093/icb/icac145. Full text in Research Archive
• Seliussen, Bjørghild Breistein; Dahle, Geir; Johansen, Torild; Besnier, Francois; Quintela, Maria & Jorde, Per Erik [Show all 11 contributors for this article] (2022). Geographic variation in gene flow from a genetically distinct migratory ecotype drives population genetic structure of coastal Atlantic cod (Gadus morhua L.). Evolutionary Applications. ISSN 1752-4571. 15(7), p. 1162–1176. doi: 10.1111/eva.13422. Full text in Research Archive
• Knutsen, Halvor; de Oliveira Catarino, Diana Sofia; Rogers, Lauren; Sodeland, Marte; Mattingsdal, Morten & Jahnke, Marlene [Show all 15 contributors for this article] (2022). Combining population genomics with demographic analyses highlights habitat patchiness and larval dispersal as determinants of connectivity in coastal fish species. Molecular Ecology. ISSN 0962-1083. 31(9), p. 2562–2577. doi: 10.1111/mec.16415. Full text in Research Archive Show summary

  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.

• Knutsen, Jan Atle; Kleiven, Alf Ring; Olsen, Esben Moland; Knutsen, Halvor; Espeland, Sigurd Heiberg & Sørdalen, Tonje Knutsen [Show all 15 contributors for this article] (2022). Lobster reserves as a management tool in coastal waters: Two decades of experience in Norway. Marine Policy. ISSN 0308-597X. 136. doi: 10.1016/j.marpol.2021.104908. Full text in Research Archive Show summary

  The positive effects of reduced fishing pressure in marine protected areas (MPAs) are now well documented globally. Yet, evidence of MPA benefits from long-term replicated before-after control-impact (BACI) studies and their usefulness in protecting target species are still rare, especially in northern temperate areas. Scientific rigor in the monitoring of MPAs is considered important for obtaining trust and compliance and can increase interest and enthusiasm for the benefits of marine conservation. Off the coast of southern Norway, a MPA imple- mentation process started up in 2002. Based on comprehensive consultations with local fishers and managers, four experimental lobster reserves were appointed in 2004. Two years later (2006), the reserves came into effect as the Norwegian Directorate of Fisheries implemented regulations as a by-law of the Saltwater Fisheries Act that effectively banned all fixed gear. Long-term monitoring of the MPAs and adjacent control areas has enabled a rigorous scientific evaluation of the effects of these MPAs on lobster populations, including effects on density, growth, demography, behavior, and phenotypic diversity. As protection effects started to manifest, the lobster reserves attracted high public attention and were soon considered a credible supplement to traditional fisheries management. In the period from 2002 to 2021, more than 50 lobster reserves have been implemented in Norway. Here, we review the experiences since the lobster reserves were designated, implemented, and embraced by local communities in Norway, and over two decades have become an important tool for fishery management. Thoughts on the future of MPAs along the coast of Norway are discussed.

• Sodeland, Marte; Jentoft, Sissel; Jorde, Per Erik; Mattingsdal, Morten; Albretsen, Jon & Kleiven, Alf Ring [Show all 12 contributors for this article] (2022). Stabilizing selection on Atlantic cod supergenes through a millennium of extensive exploitation. Proceedings of the National Academy of Sciences of the United States of America. ISSN 0027-8424. 119(8). doi: 10.1073/pnas.2114904119. Full text in Research Archive Show summary

  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.

• Moland, Even; Fernández-Chacón, Albert; Sørdalen, Tonje Knutsen; Villegas-Rios, David; Thorbjørnsen, Susanna Huneide & Halvorsen, Kim Aleksander Tallaksen [Show all 14 contributors for this article] (2021). Restoration of Abundance and Dynamics of Coastal Fish and Lobster Within Northern Marine Protected Areas Across Two Decades. Frontiers in Marine Science. ISSN 2296-7745. doi: 10.3389/fmars.2021.674756. Full text in Research Archive
• Kjesbu, Olav Sigurd; Sundby, Svein; Sandø, Anne Britt; Alix, Maud; Hjøllo, Solfrid Sætre & Tiedemann, Maik [Show all 43 contributors for this article] (2021). Highly mixed impacts of near-future climate change on stock productivity proxies in the North East Atlantic. Fish and Fisheries. ISSN 1467-2960. 23(3), p. 601–615. doi: 10.1111/faf.12635. Full text in Research Archive
• Synnes, Ann-Elin; Huserbråten, Mats Brockstedt Olsen; Knutsen, Halvor; Jorde, Per Erik; Sodeland, Marte & Moland, Even (2021). Local recruitment of Atlantic cod and putative source spawning areas in a coastal seascape. ICES Journal of Marine Science. ISSN 1054-3139. 78(10), p. 3767–3779. doi: 10.1093/icesjms/fsab226. Full text in Research Archive
• Kristensen, Martin Lykke; Olsen, Esben Moland; Moland, Even; Knutsen, Halvor; Grønkjær, Peter & Koed, Anders [Show all 8 contributors for this article] (2021). Disparate movement behavior and feeding ecology in sympatric ecotypes of Atlantic cod. Ecology and Evolution. ISSN 2045-7758. 11(16), p. 11477–11490. doi: 10.1002/ece3.7939. Full text in Research Archive
• Fernández-Chacón, Albert; Buttay, Lucie; Moland, Even; Knutsen, Halvor & Olsen, Esben Moland (2021). Demographic responses to protection from harvesting in a long-lived marine species. Biological Conservation. ISSN 0006-3207. 257, p. 1–10. doi: 10.1016/j.biocon.2021.109094. Full text in Research Archive
• Thorbjørnsen, Susanna Huneide; Moland, Even; Villegas-Ríos, David; Bleeker, Katinka; Knutsen, Halvor & Olsen, Esben Moland (2021). Selection on fish personality differs between a no-take marine reserve and fished areas. Evolutionary Applications. ISSN 1752-4571. 14(7), p. 1807–1815. doi: 10.1111/eva.13242. Full text in Research Archive
• Faust, Ellika; Jansson, Eeva; André, Carl; Halvorsen, Kim Aleksander Tallaksen; Dahle, Geir & Knutsen, Halvor [Show all 8 contributors for this article] (2021). Not that clean: Aquaculture-mediated translocation of cleaner fish has led to hybridization on the northern edge of the species' range. Evolutionary Applications. ISSN 1752-4571. 14(6), p. 1572–1587. doi: 10.1111/eva.13220. Full text in Research Archive
• Berg, Paul R.; Jorde, Per E.; Glover, Kevin A.; Dahle, Geir; Taggart, John B. & Korsbrekke, Knut [Show all 12 contributors for this article] (2021). Genetic structuring in Atlantic haddock contrasts with current management regimes. ICES Journal of Marine Science. ISSN 1054-3139. 78(1), p. 1–13. doi: 10.1093/icesjms/fsaa204. Full text in Research Archive Show summary

  The advent of novel genetic methods has made it possible to investigate population structure and connectivity in mobile marine fish species: knowledge of which is essential to ensure a sustainable fishery. Haddock (Melanogrammus aeglefinus) is a highly exploited marine teleost distributed along the coast and continental shelf on both sides of the North Atlantic Ocean. However, little is known about its population structure. Here, we present the first study using single-nucleotide polymorphism (SNP) markers to assess the genetic population structure of haddock at multiple geographic scales, from the trans-Atlantic to the local (fjord) level. Genotyping 138 SNP loci in 1329 individuals from 19 locations across the North Atlantic revealed three main genetic clusters, consisting of a Northwest Atlantic cluster, a Northeast Arctic cluster, and a Northeast Atlantic cluster. We also observed a genetically distinct fjord population and a pattern of isolation by distance in the Northeast Atlantic. Our results contrast with the current management regime for this species in the Northeast Atlantic, as we found structure within some management areas. The study adds to the growing recognition of population structuring in marine organisms in general, and fishes in particular, and is of clear relevance for the management of haddock in the Northeast Atlantic.

• Chung, Ming-Tsung; Jørgensen, Kris-Emil Mose; Trueman, Clive N.; Knutsen, Halvor; Jorde, Per Erik & Grønkjær, Peter (2020). First measurements of field metabolic rate in wild juvenile fishes show strong thermal sensitivity but variations between sympatric ecotypes. Oikos. ISSN 0030-1299. 130(2), p. 287–299. doi: 10.1111/oik.07647.
• Jørgensen, Kris-Emil M.; Neuheimer, Anna B.; Jorde, Per Erik; Knutsen, Halvor & Grønkjær, Peter (2020). Settlement processes induce differences in daily growth rates between two co-existing ecotypes of juvenile cod Gadus morhua . Marine Ecology Progress Series. ISSN 0171-8630. 650, p. 175–189. doi: 10.3354/meps13433.
• Seljestad, Gaute; Sanchez, Maria Quintela; Faust, Ellika; Halvorsen, Kim Aleksander Tallaksen; Besnier, Francois & Jansson, Eeva [Show all 11 contributors for this article] (2020). “A cleaner break”: Genetic divergence between geographic groups and sympatric phenotypes revealed in ballan wrasse (Labrus bergylta). Ecology and Evolution. ISSN 2045-7758. 10(12), p. 6120–6135. doi: 10.1002/ece3.6404. Full text in Research Archive
• Mattingsdal, Morten; Jorde, Per Erik; Knutsen, Halvor; Jentoft, Sissel; Stenseth, Nils Christian & Sodeland, Marte [Show all 10 contributors for this article] (2019). Demographic history has shaped the strongly differentiated corkwing wrasse populations in Northern Europe. Molecular Ecology. ISSN 0962-1083. p. 1–12. doi: 10.1111/mec.15310. Full text in Research Archive
• Ono, Kotaro; Knutsen, Halvor; Olsen, Esben M; Ruus, Anders; Hjermann, Dag Ø & Stenseth, Nils Chr (2019). Possible adverse impact of contaminants on Atlantic cod population dynamics in coastal ecosystems. Proceedings of the Royal Society of London. Biological Sciences. ISSN 0962-8452. 286(1908), p. 1–9. doi: 10.1098/rspb.2019.1167. Full text in Research Archive Show summary

  While many in-laboratory ecotoxicological studies have shown the adverse impact of pollutants to the fitness of an individual, direct evidence from the field on the population dynamics of wildlife animals has been lacking. Here, we provide empirical support for a negative effect of pollution on Atlantic cod (Gadus morhua) population dynamics in coastal waters of Norway by combining unique time series of juvenile cod abundance, body size, environmental concentration of toxic contaminants and a spatially structured population dynamics model. The study shows that mercury concentration might have decreased the reproductive potential of cod in the region despite the general decline in the environmental concentration of mercury, cadmium and hexachlorobenzene since the implementation of national environmental laws. However, some cod populations appeared to be more resistant to mercury pollution than others, and the strength and shape of mercury effect on cod reproductive potential was fjord-specific. Additionally, cod growth rate changed at scales smaller than fjords with a gradient related to the exposure to the open ocean and offshore cod. These spatial differences in life-history traits emphasize the importance of local adaptation in shaping the dynamics of local wildlife populations. Finally, this study highlights the possibility to mitigate pollution effects on natural populations by reducing the overall pollution level, but also reveals that pollution reduction alone is not enough to rebuild local cod populations. Cod population recovery probably requires complementary efforts on fishing regulation and habitat restoration.

• Thorbjørnsen, Susanna Huneide; Moland, Even; Simpfendorfer, Colin A.; Heupel, Michelle R.; Knutsen, Halvor & Olsen, Esben Moland (2019). Potential of a no‐take marine reserve to protect home ranges of anadromous brown trout (Salmo trutta). Ecology and Evolution. ISSN 2045-7758. 9(1), p. 417–426. doi: 10.1002/ece3.4760. Full text in Research Archive
• Barth, Julia Maria Isis; Villegas-Ríos, David; Freitas, Carla; Moland, Even; Star, Bastiaan & André, Carl [Show all 15 contributors for this article] (2019). Disentangling structural genomic and behavioral barriers in a sea of connectivity. Molecular Ecology. ISSN 0962-1083. 28(6), p. 1394–1411. doi: 10.1111/mec.15010. Full text in Research Archive
• Svedang, Hendrik; Barth, Julia Maria Isis; Svenson, Anders; Jonsson, Patrik; Jentoft, Sissel & Knutsen, Halvor [Show all 7 contributors for this article] (2019). Local cod (Gadus morhua) revealed by egg surveys and population genetic analysis after longstanding depletion on the Swedish Skagerrak coast. ICES Journal of Marine Science. ISSN 1054-3139. 76(2), p. 418–429. doi: 10.1093/icesjms/fsy166. Full text in Research Archive
• Jorde, Per Erik; Kleiven, Alf Ring; Sodeland, Marte; Olsen, Esben Moland; Ferter, Keno & Jentoft, Sissel [Show all 7 contributors for this article] (2018). Who is fishing on what stock: Population-of-origin of individual cod (Gadus morhua) in commercial and recreational fisheries. ICES Journal of Marine Science. ISSN 1054-3139. 75(6), p. 2153–2162. doi: 10.1093/icesjms/fsy080. Full text in Research Archive
• Jorde, Per Erik; Synnes, Ann-Elin; Espeland, Sigurd Heiberg; Sodeland, Marte & Knutsen, Halvor (2018). Can we rely on selected genetic markers for population identification? Evidence from coastal Atlantic cod. Ecology and Evolution. ISSN 2045-7758. 8(24), p. 12547–12558. doi: 10.1002/ece3.4648. Full text in Research Archive
• Roney, Nancy; Oomen, Rebekah Alice; Knutsen, Halvor; Olsen, Esben Moland & Hutchings, Jeffrey (2018). Fine-Scale Population Differences in Atlantic Cod Reproductive Success: A Potential Mechanism for Ecological Speciation in a Marine Fish. Ecology and Evolution. ISSN 2045-7758. p. 1–11. doi: 10.1002/ece3.4615. Full text in Research Archive
• Knutsen, Halvor; Jorde, Per Erik; Hutchings, Jeffrey; Hemmer-Hansen, Jakob; Grønkjær, Peter & Mose Jørgensen, Kris-Emil [Show all 10 contributors for this article] (2018). Stable coexistence of genetically divergent Atlantic cod ecotypes at multiple spatial scales. Evolutionary Applications. ISSN 1752-4571. 11(9), p. 1527–1539. doi: 10.1111/eva.12640. Full text in Research Archive
• Sørdalen, Tonje Knutsen; Halvorsen, Kim Aleksander Tallaksen; Harrison, Hugo B.; Ellis, Charlie D.; Vøllestad, Leif Asbjørn & Knutsen, Halvor [Show all 8 contributors for this article] (2018). Harvesting changes mating behaviour in European lobster. Evolutionary Applications. ISSN 1752-4571. 11(6), p. 963–977. doi: 10.1111/eva.12611. Full text in Research Archive
• Thorbjørnsen, Susanna Huneide; Moland, Even; Huserbråten, Mats Brockstedt Olsen; Knutsen, Jan Atle; Knutsen, Halvor & Olsen, Esben Moland (2018). Replicated marine protected areas (MPAs) support movement of larger, but not more, European lobsters to neighbouring fished areas. Marine Ecology Progress Series. ISSN 0171-8630. 595, p. 123–133. doi: 10.3354/meps12546. Full text in Research Archive
• Spies, Ingrid; Hauser, Lorenz; Jorde, Per Erik; Knutsen, Halvor; Punt, André E. & Rogers, Lauren [Show all 7 contributors for this article] (2018). Inferring genetic connectivity in real populations, exemplified by coastal and oceanic Atlantic cod. Proceedings of the National Academy of Sciences of the United States of America. ISSN 0027-8424. 115(19), p. 4945–4950. doi: 10.1073/pnas.1800096115. Full text in Research Archive
• Coscia, Ilaria; Castilho, Rita; Massa-Gallucci, Alexia; Sacchi, Carlotta; Cunha, Regina L. & Stefanni, Sergio [Show all 9 contributors for this article] (2018). Genetic homogeneity in the deep-sea grenadier Macrourus berglax across the North Atlantic Ocean. Deep Sea Research Part I: Oceanographic Research Papers. ISSN 0967-0637. 132, p. 60–67. doi: 10.1016/j.dsr.2017.12.001.
• Faust, Ellika; Halvorsen, Kim Aleksander Tallaksen; Andersen, Per; Knutsen, Halvor & André, Carl (2018). Cleaner fish escape salmon farms and hybridize with local wrasse populations. Royal Society Open Science. ISSN 2054-5703. 5(3), p. 1–12. doi: 10.1098/rsos.171752. Full text in Research Archive
• Dornelas, Maria; Antão, Laura H.; Moyes, Faye; Bates, Amanda E.; Magurran, Anne E. & Adam, Dusan [Show all 270 contributors for this article] (2018). BioTIME: A database of biodiversity time series for the Anthropocene. Global Ecology and Biogeography. ISSN 1466-822X. 27(7), p. 760–786. doi: 10.1111/geb.12729. Full text in Research Archive
• Mattingsdal, Morten; Jentoft, Sissel; Tørresen, Ole K.; Knutsen, Halvor; Hansen, Michael Möller & Robalo, Joana I. [Show all 9 contributors for this article] (2018). A continuous genome assembly of the corkwing wrasse (Symphodus melops). Genomics. ISSN 0888-7543. 110(6), p. 399–403. doi: 10.1016/j.ygeno.2018.04.009.
• Roney, Nancy; Oomen, Rebekah Alice; Knutsen, Halvor; Olsen, Esben Moland & Hutchings, Jeffrey (2018). Temporal variability in offspring quality and individual reproductive output in a broadcast-spawning marine fish. ICES Journal of Marine Science. ISSN 1054-3139. 75(4), p. 1353–1361. doi: 10.1093/icesjms/fsx232.
• Delaval, Aurelien Nicolas; Dahle, Geir; Knutsen, Halvor; Devine, Jennifer Ann & Salvanes, Anne Gro Vea (2018). Norwegian fjords contain sub-populations of roundnose grenadier Coryphaenoides rupestris, a deep-water fish. Marine Ecology Progress Series. ISSN 0171-8630. 586, p. 181–192. doi: 10.3354/meps12400.
• Jansson, Eeva; Sanchez, Maria Quintela; Dahle, Geir; Albretsen, Jon; Knutsen, Halvor & André, Carl [Show all 12 contributors for this article] (2017). Genetic analysis of goldsinny wrasse reveals evolutionary insights into population connectivity and potentialevidence of inadverent translocationvia aquaculture. ICES Journal of Marine Science. ISSN 1054-3139. 74(8), p. 2135–2147. doi: 10.1093/icesjms/fsx046. Full text in Research Archive
• Barth, Julia Maria Isis; Berg, Paul Ragnar; Jonsson, Per R; Bonanomi, Sara; Corell, Hanna & Hemmer-Hansen, Jakob [Show all 16 contributors for this article] (2017). Genome architecture enables local adaptation of Atlantic cod despite high connectivity. Molecular Ecology. ISSN 0962-1083. 26(17), p. 4452–4466. doi: 10.1111/mec.14207. Full text in Research Archive
• Star, Bastiaan; Boessenkool, Sanne; Gondek, Agata Teresa; Nikulina, Elena A.; Hufthammer, Anne Karin & Pampoulie, Christophe [Show all 16 contributors for this article] (2017). Ancient DNA reveals the Arctic origin of Viking Age cod from Haithabu, Germany. Proceedings of the National Academy of Sciences of the United States of America. ISSN 0027-8424. 114(34), p. 9152–9157. doi: 10.1073/pnas.1710186114. Full text in Research Archive
• Catarino, Diana; Stefanni, Sergio; Jorde, Per Erik; Menezes, Gui; Company, Joan B. & Neat, Francis [Show all 7 contributors for this article] (2017). The role of the Strait of Gibraltar in shaping the genetic structure of the Mediterranean Grenadier, Coryphaenoides mediterraneus, between the Atlantic and Mediterranean Sea. PLOS ONE. ISSN 1932-6203. 12(5), p. 1–24. doi: 10.1371/journal.pone.0174988. Full text in Research Archive
• Rogers, Lauren; Storvik, Geir Olve; Knutsen, Halvor; Olsen, Esben Moland & Stenseth, Nils Christian (2017). Fine-scale population dynamics in a marine fish species inferred from dynamic state-space models. Journal of Animal Ecology. ISSN 0021-8790. 86(4), p. 888–898. doi: 10.1111/1365-2656.12678. Full text in Research Archive
• Halvorsen, Kim Aleksander Tallaksen; Larsen, Torkel; Sørdalen, Tonje Knutsen; Vøllestad, Leif Asbjørn; Knutsen, Halvor & Olsen, Esben Moland (2017). Impact of harvesting cleaner fish for salmonid aquaculture assessed from replicated coastal marine protected areas. Marine Biology Research. ISSN 1745-1000. 13(4), p. 359–369. doi: 10.1080/17451000.2016.1262042. Full text in Research Archive
• Westgaard, Jon-Ivar; Saha, Atal; Kent, Matthew Peter; Hansen, Hanne Hellerud; Knutsen, Halvor & Hauser, Lorenz [Show all 9 contributors for this article] (2017). Genetic population structure in Greenland halibut (Reinhardtius hippoglossoides) and its relevance to fishery management. Canadian Journal of Fisheries and Aquatic Sciences. ISSN 0706-652X. 74(4), p. 475–485. doi: 10.1139/cjfas-2015-0430. Full text in Research Archive
• Laurel, Benjamin J.; Cote, David; Gregory, Robert S.; Rogers, Lauren; Knutsen, Halvor & Olsen, Esben Moland (2017). Recruitment signals in juvenile cod surveys depend on thermal growth conditions. Canadian Journal of Fisheries and Aquatic Sciences. ISSN 0706-652X. 74(4), p. 511–523. doi: 10.1139/cjfas-2016-0035.
• Blanco Gonzalez, Enrique ; Knutsen, Halvor & Jorde, Per Erik (2016). Habitat discontinuities separate genetically divergent populations of a rocky shore marine fish. PLOS ONE. ISSN 1932-6203. 11(10). doi: 10.1371/journal.pone.0163052. Full text in Research Archive
• Halvorsen, Kim Aleksander Tallaksen; Sørdalen, Tonje Knutsen; Durif, Caroline; Knutsen, Halvor; Olsen, Esben Moland & Skiftesvik, Anne Berit [Show all 9 contributors for this article] (2016). Male biased sexual size dimorphism in the nest building corkwing wrasse (Symphodus melops): implications for a size regulated fishery. ICES Journal of Marine Science. ISSN 1054-3139. 73(10), p. 2586–2594. doi: 10.1093/icesjms/fsw135.
• Kleiven, Alf Ring; Chacon, Albert Fernandez; Nordahl, Jan-Harald; Moland, Even; Espeland, Sigurd Heiberg & Knutsen, Halvor [Show all 7 contributors for this article] (2016). Harvest pressure on coastal atlantic cod (Gadus morhua) from recreational fishing relative to commercial fishing assessed from tag-recovery data. PLOS ONE. ISSN 1932-6203. 11(3). doi: 10.1371/journal.pone.0149595. Full text in Research Archive
• Berg, Paul Ragnar; Star, Bastiaan; Pampoulie, Christophe; Sodeland, Marte; Barth, Julia Maria Isis & Knutsen, Halvor [Show all 8 contributors for this article] (2016). Three chromosomal rearrangements promote genomic divergence between migratory and stationary ecotypes of Atlantic cod. Scientific Reports. ISSN 2045-2322. 6, p. 1–12. doi: 10.1038/srep23246. Full text in Research Archive
• Sodeland, Marte; Jorde, Per Erik; Lien, Sigbjørn; Jentoft, Sissel; Berg, Paul Ragnar & Grove, Harald [Show all 10 contributors for this article] (2016). "Islands of divergence" in the Atlantic cod genome represent polymorphic chromosomal rearrangements. Genome Biology and Evolution (GBE). ISSN 1759-6653. 8(4), p. 1012–1022. doi: 10.1093/gbe/evw057. Full text in Research Archive
• André, Carl; Svedang, Hendrik; Knutsen, Halvor; Dahle, Geir; Jonsson, Patrik & Ring, Anna-Karin [Show all 8 contributors for this article] (2016). Population structure in Atlantic cod in the eastern North Sea-Skagerrak-Kattegat: early life stage dispersal and adult migration. BMC Research Notes. ISSN 1756-0500. 9(63). doi: 10.1186/s13104-016-1878-9. Full text in Research Archive
• Sanchez, Maria Quintela; Danielsen, Elin A.; Lòpez, Lùa; Barreiro, Rodolfo; Svåsand, Terje & Knutsen, Halvor [Show all 8 contributors for this article] (2016). Is the ballan wrasse (Labrus bergylta) two species? Genetic analysis reveals within-species divergence associated with plain and spotted morphotype frequencies. Integrative Zoology. ISSN 1749-4869. 11(2), p. 162–172. doi: 10.1111/1749-4877.12186.
• Roney, Nancy E.; Hutchings, Jeffrey; Olsen, Esben Moland; Knutsen, Halvor; Albretsen, Jon & Kuparinen, Anna (2016). Fine-scale life-history structure in a highly mobile marine fish. Evolutionary Ecology Research. ISSN 1522-0613. 17, p. 95–109.
• Freitas, Carla; Olsen, Esben Moland; Knutsen, Halvor; Albretsen, Jon & Moland, Even (2016). Temperature-associated habitat selection in a cold-water marine fish. Journal of Animal Ecology. ISSN 0021-8790. 85(3), p. 628–637. doi: 10.1111/1365-2656.12458. Full text in Research Archive
• Barceló, Caren; Ciannelli, Lorenzo; Olsen, Esben Moland; Johannessen, Tore & Knutsen, Halvor (2016). Eight decades of sampling reveal a contemporary novel fish assemblage in coastal nursery habitats. Global Change Biology. ISSN 1354-1013. 22(3), p. 1155–1167. doi: 10.1111/gcb.13047.
• Knutsen, Halvor; Jorde, Per Erik; Blanco Gonzalez, Enrique ; Eigaard, Ole Ritzau; Pereyra, Ricardo T. & Sannæs, Hanne [Show all 9 contributors for this article] (2015). Does population genetic structure support present management regulations of the northern shrimp (Pandalus borealis)in Skagerrak and the North Sea? ICES Journal of Marine Science. ISSN 1054-3139. 72, p. 863–871. doi: 10.1093/icesjms/fsu204.
• Catarino, Diana; Knutsen, Halvor; Verissimo, Ana; Olsen, Esben Moland; Jorde, Per Erik & Menezes, Gui [Show all 14 contributors for this article] (2015). The Pillars of Hercules as a bathymetric barrier to gene flow promoting isolation in a global deep-sea shark (Centroscymnus coelolepis). Molecular Ecology. ISSN 0962-1083. 24(24), p. 6061–6079. doi: 10.1111/mec.13453.
• Ellis, Charlie; Hodgson, DJ; Andre, Carl; Sørdalen, Tonje Knutsen; Knutsen, Halvor & Griffiths, Amber (2015). Notes on Hardy's uncertainty principle for the Wigner distribution and Schrödinger evolutions. PLOS ONE. ISSN 1932-6203. 525(1). doi: 10.1016/j.jmaa.2023.127116. Full text in Research Archive
• Berg, Paul Ragnar; Jentoft, Sissel; Star, Bastiaan; Ring, Kristoffer Hofaker; Knutsen, Halvor & Lien, Sigbjørn [Show all 8 contributors for this article] (2015). Adaptation to low salinity promotes genomic divergence in Atlantic Cod (Gadus morhua L.). Genome Biology and Evolution (GBE). ISSN 1759-6653. 7(6), p. 1644–1663. doi: 10.1093/gbe/evv093. Full text in Research Archive
• Blanco Gonzalez, Enrique; Aritaki, Masato; Knutsen, Halvor & Taniguchi, Nobuhiko (2015). Effects of large-scale releases on the genetic structure of red sea bream (Pagrus major, Temminck et Schlegel) populations in Japan. PLOS ONE. ISSN 1932-6203. 10(5), p. 1–20. doi: 10.1371/journal.pone.0125743. Full text in Research Archive
• Freitas, Carla; Olsen, Esben Moland; Moland, Even; Ciannelli, Lorenzo & Knutsen, Halvor (2015). Behavioral responses of Atlantic cod to sea temperature changes. Ecology and Evolution. ISSN 2045-7758. 5(10), p. 2070–2083. doi: 10.1002/ece3.1496. Full text in Research Archive

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• Stenseth, Nils Christian; Jentoft, Sissel; Moland, Even; Knutsen, Halvor; Haugen, Thrond Oddvar & Colman, JE [Show all 9 contributors for this article] (2023). Langsiktig forskning og modige tiltak må til om vi skal redde Oslo­fjorden. Debattinnlegg i Khrono, 14.08.2023. khrono.no/langsiktig-forskning-og-modige-tiltak-ma-til-om-vi-skal-redde-oslofjorden/800689. Khrono.no. ISSN 1894-8995.
• Oomen, Rebekah Alice; Knutsen, Halvor; Moland, Even; Olsen, Esben Moland; Knutsen, Jan Atle & Bernatchez, Louis [Show all 8 contributors for this article] (2022). Nothing so boundless, nothing so patient: Obituary for Professor Jeffrey Alexander Hutchings (1958–2022). Fish and Fisheries. ISSN 1467-2960. 23(3), p. 519–521. doi: 10.1111/faf.12661.
• Karlsson, Sten; Skaala, Øystein; Knutsen, Halvor; Lo, Håvard & Sægrov, Harald (2020). Nasjonal kartlegging av genetisk struktur hos sjøørret.
• Stige, Leif Christian; Langangen, Øystein; Durant, Joel Marcel; Knutsen, Halvor; Olsen, Esben Moland & Ottersen, Geir (2019). Forskning på torsk. Biolog. ISSN 0801-0722. 37(2), p. 46–49.
• André, Carl; Barth, Julia Maria Isis; Jonsson, Patrik; Jentoft, Sissel; Knutsen, Halvor & Svedäng, Henrik (2019). Response to comments by Cardinale et al. on “Local cod (Gadus morhua) revealed by egg surveys and population genetic analysis after longstanding depletion on the Swedish Skagerrak coast” by Svedäng et al. (2019). ICES Journal of Marine Science. ISSN 1054-3139. 76(4), p. 1212–1213. doi: 10.1093/icesjms/fsz125.
• Oomen, Rebekah Alice; Knutsen, Halvor; Olsen, Esben Moland; Jentoft, Sissel; Stenseth, Nils Chr. & Hutchings, Jeffrey (2018). Transcriptomic variability in population responses of Atlantic cod to temperature.
• Thorbjørnsen, Susanna Huneide; Moland, Even; Villegas-Rios, David; Knutsen, Halvor & Olsen, Esben Moland (2018). Personality of sea trout and consequences for survival quantified using detailed movement data from a telemetry study in a southern Norwegian fjord.
• Blanco Gonzalez, Enrique ; Jentoft, Sissel; Hansen, Michael Møller; Knutsen, Halvor; Sodeland, Marte & Mattingsdal, Morten [Show all 9 contributors for this article] (2018). Understanding adaptation in translocating wrasses.
• Thorbjørnsen, Susanna Huneide; Moland, Even; Simpfendorfer, Colin A.; Heupel, Michelle R.; Knutsen, Halvor & Olsen, Esben Moland (2017). A no-take marine reserve provide benefits to anadromous sea trout (Salmo trutta).
• Thorbjørnsen, Susanna Huneide; Moland, Even; Villegas-Rios, David; Knutsen, Halvor & Olsen, Esben Moland (2017). Repeatability of sea trout behavioural traits and potential for detecting behavioural syndromes.
• Barth, Julia Maria Isis; Star, Bastiaan; Matschiner, Michael; André, Carl; Knutsen, Halvor & Bradbury, Ian [Show all 13 contributors for this article] (2017). Chromosomal rearrangements as barriers to homogenization in highly mobile fish.
• Barth, Julia Maria Isis; Star, Bastiaan; Matschiner, Michael; André, Carl; Knutsen, Halvor & Bradbury, Ian [Show all 13 contributors for this article] (2017). Chromosomal rearrangements as barriers to homogenization in highly mobile fish.
• Blanco Gonzalez, Enrique ; Knutsen, Halvor & Jorde, Per Erik (2016). Seascape genomics in a growing fishery: the case of a translocated cleaner fish, the corkwing wrasse (Symphodus melops).
• Oomen, Rebekah Alice; Knutsen, Halvor; Olsen, Esben Moland; Jentoft, Sissel; Stenseth, Nils Christian & Hutchings, Jeffrey (2016). Genetic variability in population responses of Atlantic cod to temperature.
• Blanco Gonzalez, Enrique; Knutsen, Halvor & Jorde, Per Erik (2015). Genetic and phenotypic characterization of local and translocated corkwing wrasse (Symphodus melops) populations.
• Oomen, Rebekah Alice; Knutsen, Halvor; Olsen, Esben Moland; Jentoft, Sissel; Stenseth, Nils Christian & Hutchings, Jeffrey (2015). The transcriptomic response of cod to temperature.
• Oomen, Rebekah Alice; Knutsen, Halvor; Olsen, Esben Moland; Jentoft, Sissel; Stenseth, Nils Christian & Hutchings, Jeffrey (2015). Genetic variability in population responses of Atlantic cod to temperature.
• Oomen, Rebekah Alice; Knutsen, Halvor; Olsen, Esben Moland; Jentoft, Sissel; Stenseth, Nils Christian & Hutchings, Jeffrey (2015). Genetic variability in population responses of Atlantic cod to environmental change and the transcriptomic response to temperature.
• Blanco Gonzalez, Enrique; Knutsen, Halvor & Jorde, Per Erik (2015). Genetic and phenotypic characterization of local and translocated corkwing wrasse (Symphodus melops) populations.
• Blanco Gonzalez, Enrique; Jorde, Per Erik & Knutsen, Halvor (2015). Climate change and the development of the corkwing wrasse (Symphodus melops) fishery in Scandinavia: genetic population structure and potential implication of translocated cleaner fish.
• Knutsen, Halvor (2015). Leppefisknæring i vekst- flytting av fisk til hvilken pris?
• Mellerud, Ida Kristin; Vøllestad, Leif Asbjørn & Knutsen, Halvor (2014). Connectivity among populations of Atlantic cod (Gadus morhua) at the Norwegian Skagerrak cod.
• Barceló, Caren & Knutsen, Halvor (2014). Eight decades of fish sampling reveal a contemporary novel fish assemblage along the Skagerrak coast of Norway.
• Oomen, Rebekah Alice; Knutsen, Halvor; Olsen, Esben Moland; Jentoft, Sissel; Stenseth, Nils Christian & Hutchings, Jeffrey A. (2014). Genetic variability in population responses of Atlantic cod to environmental change.
• Barth, Julia Maria Isis; Berg, Paul Ragnar; Star, Bastiaan; Bonanomi, Sara; Hemmer-Hansen, Jakob & Knutsen, Halvor [Show all 8 contributors for this article] (2014). A genomic perspective on cod connectivity in the Skagerrak/Kattegat.
• Berg, Paul Ragnar; Jentoft, Sissel; Star, Bastiaan; Ring, Kristoffer Hofaker; Knutsen, Halvor & Lien, Sigbjørn [Show all 8 contributors for this article] (2014). Adaptation to low salinity promotes genomic divergence in Atlantic cod (Gadus morhua L.).
• Knutsen, Halvor (2014). Facebookside Centre for Coastal Research (CCR). Show summary

  https://www.facebook.com/marinecenternorway?ref=hl

• Knutsen, Halvor & Olsen, Esben Moland (2014). Bare småtorsk til jul? [Newspaper]. Agderposten.
• Espeland, Sigurd Heiberg & Knutsen, Halvor (2023). Rapport fra høstundersøkelsene med strandnot i indre og ytre Oslofjord 2022. Havforskningsinstituttet. ISSN 1893-4536. Full text in Research Archive Show summary

  Rapporten oppsummerer resultater fra funn som ble gjort ved gjennomføring av forsøksfiske med strandnot i indre og ytre Oslofjord frem til 2022. Registreringene er gjort som del av Havforskningsinstituttets høstundersøkelse som har pågått siden 1919 (med de tilleggsstasjoner som er dekket for formål av denne rapporten). Rekruttering av torsk i Indre Oslofjord har vært svært lav de siste årene, også sett i forhold til de siste årene hvor trenden har vært på et historisk lavt nivå. Andre arter som sjøørret, er et eksempel på en art som gjør det bedre, og har hatt en liten økning de senere årene. Mer generelt har de varmekjære artene hatt et oppsving de siste 20 årene, der de pelagiske arter overtar for bentiske. Varmere klima med mer avrenning som både bidrar og til overgjødsling og formørkning gjør at naturen blir enda mer sårbar for fiske.

• Knutsen, Halvor; Espeland, Sigurd Heiberg & Moland, Even (2022). Evaluering av tiltak for vern av kysttorsk i sør innført juni 2019. Havforskningsinstituttet. ISSN 1893-4536. Full text in Research Archive Show summary

  Vi ser i våre data ingen tegn til at bestandssituasjonen for torsk er endret i indre Skagerrak, ytre- og indre Oslofjord siden tiltak ble innført i 2019. Havforskningsinstituttets data viser stabilt lave fangster av torsk i hele tiltaksområdet, selv om årene 2017 og 2019 viste forholdsvis sterke årsklasser. Landingene i yrkesfisket viser en vedvarende nedgang siden 2019. Fravær av torsk på strandnotsstasjoner i Oslofjorden innenfor Drøbak knyttes til flere forhold. Særlig er vegetasjonen på tidligere gode habitater klart dårligere sammenholdt med andre deler av Skagerrakkysten. Økt temperatur i overflaten og tilgroing av habitater med hurtigvoksende trådformede alger («lurv») bidrar trolig til dette. Avrenning, næringsbelastning og formørkning av kystvannet er også påvirkninger som bidrar i negativ retning for torsk og andre bunnfiskbestander.

• Asplin, Lars; Bienfait, André Marcel; Espeland, Sigurd Heiberg; Fall, Johanna Jennifer Elisabeth; Gagnon, Karine & Grøsvik, Bjørn Einar [Show all 17 contributors for this article] (2022). Svar på høring om tillatelse til utslipp fra foreløpig anleggsvirksomhet samt mudring, dumping og utfylling i forbindelse med bygging av Stad skipstunnel. Havforskningsinstituttet. Full text in Research Archive
• Moland, Even; Synnes, Ann-Elin; Naustvoll, Lars Johan; Freitas, Carla; Norderhaug, Kjell Magnus & Thormar, Jonas [Show all 15 contributors for this article] (2021). Krafttak for kysttorsken - Kunnskap for stedstilpasset gjenoppbygging av bestander, naturtyper og økosystem i Færder- og Ytre Hvaler nasjonalparker. Havforskningsinstituttet. ISSN 1893-4536. Full text in Research Archive Show summary

  Ytre Oslofjord har en unik kystnatur av svært stor verdi for både fastboende og tilreisende. Færder- og Ytre Hvaler nasjonalparker ligger side om side ytterst i fjorden, og skal sikre naturverdiene for kommende generasjoner. Nasjonalparkene har utformet egne forvaltningsplaner og -mål, som gjenspeiler et ønske om å legge best mulig til rette for at fiskearter, fugler, planter og insekter skal fortsette å trives innenfor parkenes grenser. Generelle mål for naturverdiene er at de skal opprettholdes med god økologisk funksjon, og et høyt biologisk mangfold.

• Boitsov, Stepan; Knutsen, Halvor; Simonsen, Jan Henrik & Frantzen, Sylvia (2020). Undersøkelse av mageinnhold i fiskeyngel og kystnære fiskearter etter utslippet av plastpellets fra M/V Trans Carrier. Havforskningsinstituttet. ISSN 1893-4536. Full text in Research Archive Show summary

  Havforskningsinstituttet har på oppdrag fra Kystverket gjennomført en undersøkelse av mageinnhold i fiskeyngel og kystnære fiskearter fra området utpekt som mest påvirket av plastpellets-utslippet fra M/V Trans Carrier tidligere i år. Det ble i september-oktober 2020 samlet inn 633 individer av ni fiskearter langs kysten i Østfold. Prøvetakingen ble utført som en del av Havforskningsinstituttets strandnotserie. Samtlige individer av fisk ble undersøkt visuelt på Havforskningsinstituttets laboratorium for mageinnhold. Det ble ikke funnet plastrester i noen av individene. Det vurderes derfor at utslippet ikke har påvirket de undersøkte fiskeartene i det berørte området.

• Espeland, Sigurd Heiberg & Knutsen, Halvor (2019). Rapport fra høstundersøkelsene med strandnot i indre og ytre Oslofjord 2018. Havforskningsinstituttet. ISSN 1893-4536. Full text in Research Archive Show summary

  Rapporten oppsummerer resultater fra funn som ble gjort ved gjennomføring av forsøksfiske med strandnot i indre og ytre Oslofjord i 2018. Registreringene er gjort som del av Havforskningsinstituttets høstundersøkelse som har pågått siden 1919 (med de tilleggsstasjoner som er dekket for formål av denne rapporten). Rekruttering av torsk i Indre Oslofjord var i 2018 svært lav, også sett i forhold til de siste årene hvor trenden har vært på et historisk lavt nivå. Det ble fanget kun 3 yngel av torsk på 56 trekk fra Sandefjord og østover. Det ble på de samme stasjonene også bare fanget 1 eldre torsk ved årets nottrekk. De varmekjære artene har hatt et oppsving de siste 20 årene, og spesielt ser vi at pelagiske arter overtar for bentiske.

• Aglen, Asgeir; Nedreaas, Kjell Harald; Moland, Even; Knutsen, Halvor; Kleiven, Alf Ring & Johannessen, Tore [Show all 11 contributors for this article] (2016). Oppdatert kunnskapsstatus om kystnær torsk i Sør Norge. Havforskningsinstituttet. ISSN 0071-5638.

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