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    • The hidden influence of large particles on ocean colour 

      Davies, Emlyn John; Basedow, Sünnje Linnéa; McKee, David (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-02-17)
      Optical constituents in the ocean are often categorized as water, phytoplankton, sediments and dissolved matter. However, the optical properties of seawater are influenced, to some degree, by scattering and absorption by all particles in the water column. Here we assess the relevant size ranges for determining the optical properties of the ocean. We present a theoretical basis supporting the hypothesis ...
    • Redefining the oceanic distribution of Atlantic salmon 

      Rikardsen, Audun H.; Righton, David; Strøm, John Fredrik; Thorstad, Eva Bonsak; Gargan, Patrick G.; Sheehan, Timothy F.; Økland, Finn; Chittenden, Cedar; Hedger, Richard David; Næsje, Tor; Renkawitz, Mark; Sturlaugsson, Johannes; Caballero, Pablo; Baktoft, Henrik; Davidsen, Jan Grimsrud; Halttunen, Elina; Wright, Serena; Finstad, Bengt; Aarestrup, Kim (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-06-10)
      Determining the mechanisms driving range-wide reductions in Atlantic salmon marine survival is hindered by an insufcient understanding of their oceanic ecology and distribution. We attached 204 pop-up satellite archival tags to post-spawned salmon when they migrated to the ocean from seven European areas and maiden North American salmon captured at sea at West Greenland. Individuals migrated ...
    • Early spring subglacial discharge plumes fuel under-ice primary production at a Svalbard tidewater glacier 

      Vonnahme, Tobias; Persson, Emma; Dietrich, Ulrike; Hejdukova, Eva; Dybwad, Christine; Elster, Josef; Chierici, Melissa; Gradinger, Rolf (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-27)
      Subglacial upwelling of nutrient-rich bottom water is known to sustain elevated summer primary production in tidewater-glacier-influenced fjord systems. However, the importance of subglacial upwelling during the early spring season has not been considered yet. We hypothesized that subglacial discharge under sea ice is present in early spring and that its flux is sufficient to increase phytoplankton ...
    • Dense mesopelagic sound scattering layer and vertical segregation of pelagic organisms at the Arctic-Atlantic gateway during the midnight sun 

      Priou, Pierre; Nikolopoulos, Anna; Flores, Hauke; Gradinger, Rolf; Kunisch, Eirin; Katlein, Christian; Castellani, Giulia; Linders, Torsten Theodor; Berge, Jørgen; Fisher, Jonathan A.D.; Geoffroy, Maxime (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-05-18)
      Changes in vertical and spatial distributions of zooplankton and small pelagic fish impact the biological carbon pump and the distribution of larger piscivorous fish and marine mammal species. However, their distribution and abundance remain poorly documented at high latitudes because of the difficulties inherent to sampling relatively fast-moving organisms in ice-covered waters. This study documents ...
    • Summer and winter MgCO3 levels in the skeletons of Arctic bryozoans 

      Iglikowska, Anna; Krzemińska, Małgorzata; Renaud, Paul Eric; Berge, Jørgen; Hop, Haakon; Kuklinski, Piotr (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-02)
      <p>In the Arctic, seasonal patterns in seawater biochemical conditions are shaped by physical, chemical, and biological processes related to the alternation of seasons, i.e. winter polar night and summer midnight sun. In summertime, CO<sub>2</sub> concentration is driven by photosynthetic activity of autotrophs which raises seawater pH and carbonate saturation state (Ω). In addition, restriction of ...
    • Caligus elongatus and other sea lice of the genus Caligus as parasites of farmed salmonids: A review 

      Hemmingsen, Willy; MacKenzie, Ken; Sagerup, Kjetil; Remen, Mette; Bloch-Hansen, Karin; Imsland, Albert (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-02-24)
      This review was prompted by reports of unusually large numbers of sea lice tentatively identified as <i>Caligus elongatus</i> infesting farmed salmon in northern Norway. Following a brief introduction to the sea lice problem in salmonid aquaculture, the review is divided into a further eight sections. The first is a review of existing information on the life cycle and behaviour of <i>Caligus</i> ...
    • Arctic coastal benthos long-term responses to perturbations under climate warming: Climate change impact on Arctic benthos 

      Keck, Amalia; Kortsch, Susanne; Bluhm, Bodil; Beuchel, frank; Gulliksen, Bjørn; Ballantine, Carl; Cristini, Domiziana; Primicerio, Raul (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-31)
      <p>Climate warming influences structure and function of Arctic benthic ecosystems. Assessing the response of these systems to perturbations requires long-term studies addressing key ecological processes related to recolonization and succession of species. Based on unique time-series (1980–2017), this study addresses successional patterns of hard-bottom benthos in two fjords in NW Svalbard after a ...
    • Biogeography of epibenthic assemblages in the central Beaufort Sea 

      Ravelo, Alexandra M.; Bluhm, Bodil; Foster, Nora; Iken, Katrin (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-01-27)
      Benthic communities change drastically in both biomass and community structure with increasing water depth on a global scale, attributed to a combination of food supply, environmental drivers, as well as physiological and competitive capacities. In the Arctic, benthic biogeographic patterns are additionally thought to be a result of the region’s glaciation history. Here, we investigate gross epibenthic ...
    • New species of aquatic chytrids from Oman 

      Hassett, Brandon; Al-Shaibi, Badriya K.; Al-Nabhani, Abdulrahman; Al-Sadi, Abdullah M. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-12)
      Oman is a desert country in the south of the Middle East. Springs and other water sources that harbor aquatic organisms can be separated by hundreds of kilometers. In Oct 2019, we isolated four freshwater aquatic fungi (Chytridiomycota) from benthic detritus baited with pine pollen on a general nutrient medium near Salalah, Oman. Database queries of nuc 28S rRNA (28S) and internal transcribed spacer ...
    • Adaptive niche-based sampling to improve ability to find rare and elusive species: Simulations and field tests 

      Chiffard, Jules; Marciau, Coline; Yoccoz, Nigel; Mouillot, Florent; Duchateau, Stéphane; Nadeau, Iris; Fontanilles, Philippe; Besnard, Aurélien (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-27)
      <ol> <li>Sampling efficiency is crucial to overcome the data crisis in biodiversity and to understand what drives the distribution of rare species.</li <li>Adaptive niche‐based sampling (ANBS) is an iterative sampling strategy that relies on the predictions of species distribution models (SDMs). By predicting highly suitable areas to guide prospection, ANBS could improve the efficiency of sampling ...
    • Nest association between two predators as a behavioral response to the low density of rodents 

      Pokrovsky, Ivan G.; Ehrich, Dorothee; Fufachev, Ivan A.; Ims, Rolf Anker; Kulikova, Olga; Sokolov, Aleksandr; Sokolova, Natalia; Sokolov, Vasiliy; Yoccoz, Nigel (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-11-04)
      Many birds nest in association with aggressive birds of other species to benefit from their protection against predators. We hypothesized that the protective effect also could extend to foraging resources, whereby the resultant resource-enriched habitats near a nest of aggressive raptors could be an alternative cause of associations between nesting bird species with non-overlapping foraging niches. ...
    • Phytoplankton community succession and dynamics using optical approaches 

      Fragoso, Glaucia Moreira; Johnsen, Geir; Chauton, Matilde Skogen; Cottier, Finlo Robert; Ellingsen, Ingrid H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-04)
      The phytoplankton in coastal regions are responding to constant environmental changes, thus the use of proxies derived from in situ frequent time-series observations and validated from traditional microscopic or pigment methods can be a solution for detecting rapid responses of community dynamics and succession. In this study, we combined in situ high-frequency (every 30 min from May to September ...
    • Geographic hierarchical population genetic structuring in British European whitefish (Coregonus lavaretus) and its implications for conservation 

      Crotti, M; Adams, Colin Ean; Etheridge, Elizabeth C.; Bean, Colin W.; Gowans, Andrew R.D.; Knudsen, Rune; Lyle, Alex A.; Maitland, P. S.; Winfield, Ian J.; Elmer, K. R.; Præbel, Kim (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-04)
      The European whitefish <i>Coregonus lavaretus</i> complex represents one of the most diverse radiations within salmonids, with extreme morphological and genetic differentiation across its range. Such variation has led to the assignment of many populations to separate species. In Great Britain, the seven native populations of <i>C. lavaretus</i> (two in Scotland, four in England, one in Wales) were ...
    • High parasite diversity in the amphipod Gammarus lacustris in a subarctic lake 

      Shaw, Jenny Carolyn; Henriksen, Eirik Haugstvedt; Knudsen, Rune; Kuhn, Jesper Andreas; Kuris, Armand M.; Lafferty, Kevin D.; Siwertsson, Anna; Soldánová, Miroslava; Amundsen, Per-Arne (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-05)
      Amphipods are often key species in aquatic food webs due to their functional roles in the ecosystem and as intermediate hosts for trophically transmitted parasites. Amphipods can also host many parasite species, yet few studies address the entire parasite community of a gammarid population, precluding a more dynamic understanding of the food web. We set out to identify and quantify the parasite ...
    • Does the Infectious Status of Aphids Influence Their Preference Towards Healthy, Virus-Infected and Endophytically Colonized Plants? 

      Fingu-Mabola, Junior Corneille; Martin, Clément; Bawin, Thomas; Verheggen, François Jean; Francis, Frédéric (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-07-11)
      Aphids (Hemiptera: Aphididae) cause significant damage and transmit viruses to various crop plants. We aimed to evaluate how the infectious status of aphids influences their interaction with potential hosts. Two aphid (Myzus persicae and Rhopalosiphum padi) and plant (Nicotiana tabacum and Triticum aestivum) species were used. The preferences of aphids towards healthy, virus-infected (Potato Leafroll ...
    • Best environmental predictors of breeding phenology differ with elevation in a common woodland bird species 

      Bison, Marjorie; Yoccoz, Nigel; Carlson, Bradley; Klein, Geoffrey; Laigle, Idaline; Van Reeth, Colin; Asse, Daphné; Delestrade, Anne (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-08-17)
      Temperatures in mountain areas are increasing at a higher rate than the Northern Hemisphere land average, but how fauna may respond, in particular in terms of phenology, remains poorly understood. The aim of this study was to assess how elevation could modify the relationships between climate variability (air temperature and snow melt‐out date), the timing of plant phenology and egg‐laying date of ...
    • Understanding and managing the interactions of impacts from nature-based recreation and climate change 

      Monz, Christopher; Gutzwiller, Kevin J.; Hausner, Vera Helene; Brunson, Mark W.; Buckley, Ralf; Pickering, Catherine (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-04)
      Disturbance to ecosystems in parks and protected areas from nature-based tourism and recreation is increasing in scale and severity, as are the impacts of climate change—but there is limited research examining the degree to which these anthropogenic disturbances interact. In this perspective paper, we draw on the available literature to expose complex recreation and climate interactions that may ...
    • Acceptance of near-natural greenspace management relates to ecological and socio-cultural assigned values among European urbanites 

      Lampinen, Jussi; Tuomi, Maria; Bucharova, Anna; Cancellieri, Laura; Casado-Arzuaga, Izaskun; Deák, Balázs; Eriksson, Ove; Fernández de Manuel, Beatriz; Filibeck, Goffredo; Kowarik, Ingo; Pons, Xavier; Schröder, Roland; Sperandii, Marta Gaia; Valkó, Orsolya (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-31)
      Grasslands are widespread elements of urban greenspace providing recreational, psychological and aesthetic benefits to city residents. Two urban grassland types of contrasting management dominate urban greenspaces: frequently mown, species-poor short-cut lawns and less intensively managed, near-natural tall-grass meadows. The higher conservation value of tall-grass meadows makes management interventions ...
    • Strong migratory connectivity across meta-populations of sympatric North Atlantic seabirds 

      Merkel, Benjamin; Descamps, Sebastien; Yoccoz, Nigel; Grémillet, David; Fauchald, Per; Danielsen, Jóhannis; Daunt, Francis; Erikstad, Kjell E.; Ezhov, Aleksey V.; Harris, Mike P.; Gavrilo, Maria; Lorentsen, Svein-Håkon; Reiertsen, Tone Kristin; Systad, Geir Helge Rødli; Thórarinsson, Thorkell Lindberg; Wanless, Sarah; Strøm, Hallvard (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-04)
      Identifying drivers of population trends in migratory species is difficult, as they can face many stressors while moving through different areas and environments during the annual cycle. To understand the potential of migrants to adjust to perturbations, it is critical to study the connection of different areas used by different populations during the annual cycle (i.e. migratory connectivity). ...
    • Stomping in silence: Conceptualizing trampling effects on soils in polar tundra 

      Tuomi, Maria; Väisänen, Maria; Ylänne, H; Brearley, Francis Q.; Barrio, Isabel C.; Bråthen, Kari Anne; Eischeid, Isabell; Forbes, Bruce C.; Jónsdóttir, Ingibjörg; Kolstad, Anders Lorentzen; Macek, Petr; Petit Bon, Matteo; Speed, James David Mervyn; Stark, Sari; Svavarsdóttir, Kristin; Thorsson, Johann; Bueno, C. Guillermo (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-24)
      <ol> <li>Ungulate trampling modifies soils and interlinked ecosystem functions across biomes. Until today, most research has focused on temperate ecosystems and mineral soils while trampling effects on cold and organic matter‐rich tundra soils remain largely unknown.</li><p> <p><li>We aimed to develop a general model of trampling effects on soil structure, biota, microclimate and biogeochemical ...