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4. Earlier sea-ice melt extends the oligotrophic summer period in the Barents Sea with low algal biomass and associated low vertical flux

Author

Kohlbach, Doreen, Goraguer, Lucie, Bodur, Yasemin V., Müller, Oliver, Amargant-Arumí, Martí, Blix, Katalin, Bratbak, Gunnar, Chierici, Melissa, Dąbrowska, Anna Maria, Dietrich, Ulrike, Edvardsen, Bente, García, Laura M., Gradinger, Rolf, Hop, Haakon, Jones, Elizabeth, Lundesgaard, Øyvind, Olsen, Lasse M., Reigstad, Marit, Saubrekka, Karoline, Tatarek, Agnieszka, Wiktor, Józef Maria, Wold, Anette, and Assmy, Philipp

Published
2023
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7. A review of the scientific knowledge of the seascape off Dronning Maud Land, Antarctica

Author

Lowther, Andrew, von Quillfeldt, Cecilie, Assmy, Philipp, De Steur, Laura, Descamps, Sebastien, Divine, Dmitry, Elvevold, Synnøve, Forwick, Matthias, Fransson, Agneta, Fraser, Alexander, Gerland, Sebastian, Granskog, Mats, Hallanger, Ingeborg, Hattermann, Tore, Itkin, Mikhail, Hop, Haakon, Husum, Katrine, Kovacs, Kit, Lydersen, Christian, Matsuoka, Kenichi, Miettinen, Arto, Moholdt, Geir, Moreau, Sebastien, Myhre, Per Inge, Orme, Lisa, Pavlova, Olga, and Tandberg, Ann Helene

Published
2022
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9. A review of climate change impacts on migration patterns of marine vertebrates in Arctic and Subarctic ecosystems.

Author

Kuletz, Katherine J., Ferguson, Steven H., Frederiksen, Morten, Gallagher, Colin P., Hauser, Donna D. W., Hop, Haakon, Kovacs, Kit M., Lydersen, Christian, Mosbech, Anders, and Seitz, Andrew C.

Subjects
FISH migration, ZOOGEOGRAPHY, MIGRATORY animals, ANIMAL migration, PLANKTON blooms
Abstract

Climate change is impacting marine ecosystems throughout the circumpolar Arctic, altering seasonal habitats and the food bases for fishes, seabirds, and marine mammals. Arctic and Subarctic regions provide resources for resident species and for species that migrate to the north from more southerly regions. Changes in northerly latitudes thus impact endemic as well as non-endemic animals. Herein, we review what is known about climate-driven changes in the migration patterns of Arctic and Subarctic marine vertebrates, including: 1) Arctic residents with seasonal movements – those fishes, seabirds, and marine mammals that complete their entire life cycle within the Arctic but exhibit seasonal movements; 2) Breeding migrants – many seabirds enter the Arctic to breed and subsequently migrate south in the fall; and 3) Summer visitors for feeding – certain species of boreal fishes, seabirds and marine mammals arrive during the northern summer to feed on abundant prey though they breed elsewhere. Migratory movements are often driven by the timing and extent of sea ice, which defines suitable habitat for some animals and limits access to open water and prey for others. Longer open-water seasons, warmer ocean temperatures, and stronger winds have resulted in earlier production blooms in spring and often, extended open-ocean plankton blooms into late summer, resulting in altered prey types and distributions. A common thread among taxa is that shifts in distribution and timing of migrating animals indicate they are traveling farther north, or shifting longitudinally, and migrations are occurring over longer seasonal time frames. Species performing multiple lifetime migrations or long-distance migrants may need to adjust migration timing or routing iteratively to match changes in marine productivity. Altered animal distributions or phenology, and reduced sea ice, affects access to animals that are critical nutritional, economical, and cultural components of Indigenous people's lives in the Arctic. Ongoing changes challenge the resilience and adaptability of Arctic people and ecosystems, and will require adaptive research and management approaches. [ABSTRACT FROM AUTHOR]

Published
2024
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21. Still Arctic? - The changing Barents Sea

Author

Gerland, Sebastian, primary, Ingvaldsen, Randi B., additional, Reigstad, Marit, additional, Sundfjord, Arild, additional, Bogstad, Bjarte, additional, Chierici, Melissa, additional, Eldevik, Tor, additional, Hop, Haakon, additional, Renaud, Paul E., additional, Smedsrud, Lars H., additional, Stige, Leif Christian, additional, and Årthun, Marius, additional

Published
2024
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32. Kongsfjorden as Harbinger of the Future Arctic: Knowns, Unknowns and Research Priorities

Author

Bischof, Kai, primary, Convey, Peter, additional, Duarte, Pedro, additional, Gattuso, Jean-Pierre, additional, Granberg, Maria, additional, Hop, Haakon, additional, Hoppe, Clara, additional, Jiménez, Carlos, additional, Lisitsyn, Leonid, additional, Martinez, Brezo, additional, Roleda, Michael Y., additional, Thor, Peter, additional, Wiktor, Józef M., additional, and Gabrielsen, Geir Wing, additional

Published
2019
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36. Interactive effects of ocean acidification and temperature on oxygen uptake rates in Calanus hyperboreus nauplii

Author

Espinel-Velasco, Nadjejda, Gawinski, Christine, Kohlbach, Doreen, Pitusi, Vanessa, Graeve, Martin, Hop, Haakon, Espinel-Velasco, Nadjejda, Gawinski, Christine, Kohlbach, Doreen, Pitusi, Vanessa, Graeve, Martin, and Hop, Haakon

Abstract

The Arctic region is undergoing rapid and significant changes, characterized by high rates of acidification and warming. These transformations prompt critical questions about the resilience of marine communities in the face of environmental change. In the Arctic, marine zooplankton and in particular calanoid copepods play a vital role in the food web. Changes in environmental conditions could disrupt zooplankton communities, posing detrimental consequences for the entire ecosystem. Copepod early-life stages have been shown to be particularly sensitive to environmental stressors since they represent a bottleneck in the life cycle. Here, we investigated the responses of 4-day old Calanus hyperboreus nauplii when exposed to acidification (pH 7.5 and 8.1) and warming (0 and 3°C), both independently and in combination. Naupliar respiration rates increased when exposed to a combination of acidification and warming, but not when exposed to the stressors individually. Moreover, we found no discernible differences in lipid content and fatty acid (FA) composition of the nauplii across the different experimental treatments. Wax esters accounted for approximately 75% of the lipid reserves, and high amounts of long chain fatty acids 20:1 and 22:1, crucial for the reproduction cycle in copepods, were also detected. Our results indicate a sensitivity of these nauplii to a combination of acidification and warming, but not to the individual stressors, aligning with a growing body of evidence from related studies. This study sheds light on the potential implications of global change for Arctic copepod populations by elucidating the responses of early-life stages to these environmental stressors.

Published
2023

37. The circumpolar impacts of climate change and anthropogenic stressors on Arctic cod (Boreogadus saida) and its ecosystem

Author

Geoffroy, Maxime, Bouchard, Caroline, Flores, Hauke, Robert, Dominique, Gjøsæter, Harald, Hoover, Carie, Hop, Haakon, Hussey, Nigel E., Nahrgang, Jasmine, Steiner, Nadja, Bender, Morgan, Berge, Jørgen, Castellani, Giulia, Chernova, Natalia, Copeman, Louise, David, Carmen L., Deary, Alison, Divoky, George, Dolgov, Andrey V., Duffy-Anderson, Janet, Dupont, Nicolas, Durant, Joël M., Elliott, Kyle, Gauthier, Stéphane, Goldstein, Esther D., Gradinger, Rolf, Hedges, Kevin, Herbig, Jennifer, Laurel, Ben, Loseto, Lisa, Maes, Sarah, Mark, Felix C., Mosbech, Anders, Pedro, Sara, Pettitt-Wade, Harri, Prokopchuk, Irina, Renaud, Paul E., Schembri, Sarah, Vestfals, Cathleen, Walkusz, Wojciech, Geoffroy, Maxime, Bouchard, Caroline, Flores, Hauke, Robert, Dominique, Gjøsæter, Harald, Hoover, Carie, Hop, Haakon, Hussey, Nigel E., Nahrgang, Jasmine, Steiner, Nadja, Bender, Morgan, Berge, Jørgen, Castellani, Giulia, Chernova, Natalia, Copeman, Louise, David, Carmen L., Deary, Alison, Divoky, George, Dolgov, Andrey V., Duffy-Anderson, Janet, Dupont, Nicolas, Durant, Joël M., Elliott, Kyle, Gauthier, Stéphane, Goldstein, Esther D., Gradinger, Rolf, Hedges, Kevin, Herbig, Jennifer, Laurel, Ben, Loseto, Lisa, Maes, Sarah, Mark, Felix C., Mosbech, Anders, Pedro, Sara, Pettitt-Wade, Harri, Prokopchuk, Irina, Renaud, Paul E., Schembri, Sarah, Vestfals, Cathleen, and Walkusz, Wojciech

Abstract

Arctic cod (Boreogadus saida) is the most abundant forage fish in the Arctic Ocean. Here we review Arctic cod habitats, distribution, ecology, and physiology to assess how climate change and other anthropogenic stressors are affecting this key species. This review identifies vulnerabilities for different life stages across the entire distribution range of Arctic cod. We explore the impact of environmental (abiotic and biotic) and anthropogenic stressors on Arctic cod with a regional perspective in a scenario up to the year 2050 and identify knowledge gaps constraining predictions. Epipelagic eggs and larvae are more vulnerable to climate change and stressors than adults. Increased water temperatures, sea-ice decline, altered freshwater input, acidification, changing prey field, increased interspecific competition, new predators, and pollution are the principal stressors that will affect Arctic cod populations. Detrimental effects are likely to be greater in regions characterized by the advection of warmer Atlantic and Pacific waters. In contrast, Arctic cod may benefit from ocean warming in colder areas of the High Arctic. The risk from fisheries is moderate and primarily limited to bycatch. Overall, a decrease in suitable habitat and an associated decline in total Arctic cod biomass are predicted. In most Arctic seas, the relative abundance of Arctic cod within the fish community will likely fluctuate in accordance with cold and warm periods. A reduced abundance of Arctic cod will negatively affect the abundance, distribution, and physiological condition of certain predators, whereas some predators will successfully adapt to a more boreal diet. Regional management measures that recognize the critical role of Arctic cod are required to ensure that increased anthropogenic activities do not exacerbate the impacts of climate change on Arctic marine ecosystems. Ultimately, the mitigation of habitat loss for Arctic cod will only be achieved through a global reduction in

Published
2023

40. A red tide in the pack ice of the Arctic Ocean

Author

Olsen, Lasse M., Duarte, Pedro, Peralta-Ferriz, Cecilia, Kauko, Hanna M., Johansson, Malin, Peeken, Ilka, Różańska-Pluta, Magdalena, Tatarek, Agnieszka, Wiktor, Jozef, Fernández-Méndez, Mar, Wagner, Penelope M., Pavlov, Alexey K., Hop, Haakon, and Assmy, Philipp

Published
2019
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41. Dependency of Arctic zooplankton on pelagic food sources: New insights from fatty acid and stable isotope analyses.

Author

Kohlbach, Doreen, Lebreton, Benoit, Guillou, Gaёl, Wold, Anette, Hop, Haakon, Graeve, Martin, and Assmy, Philipp

Subjects
STABLE isotope analysis, ZOOPLANKTON, MARINE zooplankton, FATTY acids, FOOD chains, ORGANIC foods, RHEOLOGY, GLOBAL warming
Abstract

Global warming causes dramatic environmental change to Arctic ecosystems. While pelagic primary production is initiated earlier and its intensity can be increased due to earlier ice melt and extended open‐water periods, sea‐ice primary production is progressively confined on a spatio‐temporal scale, leading to unknown consequences for the ice‐associated (sympagic) food web. Understanding ecological responses to changes in the availability and composition of pelagic and sympagic food sources is crucial to determine potential changes of food‐web structure and functioning in Arctic marine communities under increasingly ice‐free conditions. Focus was placed on the importance of suspended particulate organic matter vs. sympagic organic matter for 12 zooplankton species with different feeding modes covering five taxonomic groups (copepods, krill, amphipods, chaetognaths, and appendicularians) at two ice‐covered, but environmentally different, stations in the north‐western Barents Sea in August 2019. Contributions of diatom‐ and flagellate‐associated fatty acids (FAs) to total lipid content and carbon stable isotopic compositions of these FAs were used to discriminate food sources and trace flows of organic matter in marine food webs. Combination of proportional contributions of FA markers with FA isotopic composition indicated that consumers mostly relied, directly (herbivorous species), or indirectly (omnivorous and carnivorous species), on pelagic diatoms and flagellates, independently of environmental conditions at the sampling locations, trophic position, and feeding mode. Differences were nevertheless observed between species. Contrary to other studies demonstrating a high importance of sympagic organic matter for food‐web processes, our results highlight the complexity and variability of trophic structures and dependencies in different Arctic food webs. [ABSTRACT FROM AUTHOR]

Published
2023
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42. The circumpolar impacts of climate change and anthropogenic stressors on Arctic cod (Boreogadus saida) and its ecosystem

Author

Geoffroy, Maxime, primary, Bouchard, Caroline, additional, Flores, Hauke, additional, Robert, Dominique, additional, Gjøsæter, Harald, additional, Hoover, Carie, additional, Hop, Haakon, additional, Hussey, Nigel E., additional, Nahrgang, Jasmine, additional, Steiner, Nadja, additional, Bender, Morgan, additional, Berge, Jørgen, additional, Castellani, Giulia, additional, Chernova, Natalia, additional, Copeman, Louise, additional, David, Carmen L., additional, Deary, Alison, additional, Divoky, George, additional, Dolgov, Andrey V., additional, Duffy-Anderson, Janet, additional, Dupont, Nicolas, additional, Durant, Joël M., additional, Elliott, Kyle, additional, Gauthier, Stéphane, additional, Goldstein, Esther D., additional, Gradinger, Rolf, additional, Hedges, Kevin, additional, Herbig, Jennifer, additional, Laurel, Ben, additional, Loseto, Lisa, additional, Maes, Sarah, additional, Mark, Felix C., additional, Mosbech, Anders, additional, Pedro, Sara, additional, Pettitt-Wade, Harri, additional, Prokopchuk, Irina, additional, Renaud, Paul E., additional, Schembri, Sarah, additional, Vestfals, Cathleen, additional, and Walkusz, Wojciech, additional

Published
2023
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43. Still Arctic?—The changing Barents Sea

Author

Gerland, Sebastian, primary, Ingvaldsen, Randi B., additional, Reigstad, Marit, additional, Sundfjord, Arild, additional, Bogstad, Bjarte, additional, Chierici, Melissa, additional, Hop, Haakon, additional, Renaud, Paul E., additional, Smedsrud, Lars Henrik, additional, Stige, Leif Christian, additional, Årthun, Marius, additional, Berge, Jørgen, additional, Bluhm, Bodil A., additional, Borgå, Katrine, additional, Bratbak, Gunnar, additional, Divine, Dmitry V., additional, Eldevik, Tor, additional, Eriksen, Elena, additional, Fer, Ilker, additional, Fransson, Agneta, additional, Gradinger, Rolf, additional, Granskog, Mats A., additional, Haug, Tore, additional, Husum, Katrine, additional, Johnsen, Geir, additional, Jonassen, Marius O., additional, Jørgensen, Lis Lindal, additional, Kristiansen, Svein, additional, Larsen, Aud, additional, Lien, Vidar S., additional, Lind, Sigrid, additional, Lindstrøm, Ulf, additional, Mauritzen, Cecilie, additional, Melsom, Arne, additional, Mernild, Sebastian H., additional, Müller, Malte, additional, Nilsen, Frank, additional, Primicerio, Raul, additional, Søreide, Janne E., additional, van der Meeren, Gro I., additional, and Wassmann, Paul, additional

Published
2023
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45. Panel-based Assessment of Ecosystem Condition of Norwegian Barents Sea Shelf Ecosystems

Author

Siwertsson, Anna, Husson, Berengere, Arneberg, Per, Assmann, Karen, Assmy, Philipp, Aune, Magnus, Bogstad, Bjarte, Børsheim, Knut Yngve, Cochrane, Sabine K.J., Daase, Malin, Fauchald, Per, Frainer, André, Fransson, Agneta, Hop, Haakon, Höffle, Hannes, Gerland, Sebastian, Ingvaldsen, Randi Brunvær, Jentoft, Sissel, Kovacs, Kit M., Leonard, Deanna Marie, Lind, Sigrid, Lydersen, Christian, Pavlova, Olga, Peuchet, Laurene, Primicerio, Raul, Renaud, Paul Eric, Solvang, Hiroko Kato, Skaret, Georg, van der Meeren, Gro Ingleid, Wassmann, Paul, and Øien, Nils Inge

Abstract

The 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 anthropogenic activities. An ecosystem in good ecological condition is defined as a system that does not deviate substantially from this reference condition in structure, functions or productivity. This means that, in practice, what is assessed here is the extent to which an ecosystem is impacted by anthropogenic drivers. This report describes the first operational assessment of the ecological condition of Norwegian Arctic and Sub-Arctic marine shelf ecosystems in the Barents Sea. The assessment method employed is the Panel-based Assessment of Ecosystem Condition (PAEC1), and the current assessment has considered to what extent the Barents Sea shelf ecosystems deviate from the reference condition2 by evaluating change trajectories. Panel-based Assessment of Ecosystem Condition of Norwegian Barents Sea Shelf Ecosystems

Published
2023

46. Panel-based Assessment of Ecosystem Condition of Norwegian Barents Sea Shelf Ecosystems - Appendices

Author

Siwertsson, Anna, Husson, Berengere, Arneberg, Per, Assmann, Karen, Assmy, Philipp, Aune, Magnus, Bogstad, Bjarte, Børsheim, Knut Yngve, Cochrane, Sabine K.J., Daase, Malin, Fauchald, Per, Frainer, André, Fransson, Agneta, Hop, Haakon, Höffle, Hannes, Gerland, Sebastian, Ingvaldsen, Randi Brunvær, Jentoft, Sissel, Kovacs, Kit M., Leonard, Deanna Marie, Lind, Sigrid, Lydersen, Christian, Pavlova, Olga, Peuchet, Laurene, Primicerio, Raul, Renaud, Paul Eric, Solvang, Hiroko Kato, Skaret, Georg, van der Meeren, Gro Ingleid, Wassmann, Paul, and Øien, Nils Inge

Abstract

Source at https://hi.no/hi.

Published
2023

50. Seasonal cruise Q2 2021

Author

Ludvigsen, Martin, Assmy, Philipp, Adams, Matthew James Samuel, Amargant-Arumí, Martí, Mo-Bjørkelund, Tore, Bodur, Yasemin, Bremnes, Jens Einar, Flo, Snorre, Gawinski, Christine, Giebichtenstein, Julia, Halvorsen, Elisabeth, Hatlebakk, Maja, Hess, Silvia, Hop, Haakon, Itkin, Polona, Jones, Elizabeth, Karlsson, Konrad, Keck, Amalia, Kohlbach, Doreen, Kohler, Stephen Gustav, Krapp, Rupert, Leopold, Peter, Marquardt, Miriam, Jorda Molina, Eric, Nowicki, Robynne, Mork Olsen, Lasse, Anglada Ortiz, Griselda, Petit, Tristan, Ricardo de Freitas, Thaise, Saubrekka, Karoline, Sen, Arunima, Steer, Adam, Summers, Natalie, Thiele, Stefan, Thorstensen, Helene, and Vihtakari, Mikko

Abstract

The spring season was the target for the Nansen Legacy cruise organized in late April and first half of May 2021 following the transect defined for this series of cruises to capture the variations of the year sampling physical, biological and chemical conditions in the ice and the sea. The transect went through both open water and ice. Seven process stations were visited (P1 through P7) together with smaller NLEG stations according to the program for the seasonal investigations. The first station (P1) was in open waters, while the remaining six main station had ice coverage of varying degree. Each of the process stations lasted 24 hours or more to allow a full diurnal cycle. Sampling included ice physics, ice samples, phytoplankton, zooplankton, marine chemistry and eco toxicology using acoustic, optical and robotics methods together with lab analyses of physical samples. Remote sensing data were also matched with in situ observations of both sea and ice conditions.

Published
2022
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