Now showing items 21-40 of 1914

    • Dechloranes and chlorinated paraffins in sediments and biota of two subarctic lakes 

      Arriola, Aline; Al Saify, Insam; Warner, Nicholas Alexander; Herzke, Dorte; Harju, Mikael; Amundsen, Per-Arne; Evenset, Anita; Möckel, Claudia; Krogseth, Ingjerd Sunde (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-16)
      Our understanding of the environmental behavior, bioaccumulation and concentrations of chlorinated paraffins (CPs) and Dechloranes (Dec) in the Arctic environment is still limited, particularly in freshwater ecosystems. In this descriptive study, short chain (SCCPs) and medium chain (MCCPs) CPs, Dechlorane Plus (DP) and analogues, and polychlorinated biphenyls (PCBs) were measured in sediments, ...
    • Bestandskartlegging av kongekrabbe i kvoteregulert område – 2022 - Toktrapport fra tokt med F/F Kristine Bonnevie 05. september – 26. september 2022 (2022624) 

      Hjelset, Ann Merete; Jenssen, Maria; Schuster, Erik; Olsen, Siri Aaserud; Larsen, Marita; Danielsen, Hanna Ellerine Helle; Olssøn, Ragni; Fuhrmann, Mona Maria; Johannesen, Reidar (Research report; Forskningsrapport, 2024-06-05)
      Havforskningsinstituttet skal gi råd og kunnskapsgrunnlag for kvotefastsetting og regulering av fisket på kongekrabbe til forvaltningsmyndighetene. <p> <p>Hensikten med toktet var å kartlegge bestanden av kongekrabbe i kvoteregulert område i Øst-Finnmark. Toktet inngår i en lang tidsserie som danner grunnlaget for den årlige kvoteanbefalingen og overvåkningen av utviklingen i kongekrabbebestanden.
    • Temporal variation in marine mammal species assemblage at South Orkney Islands revealed through passive acoustic data from 2016 and 2017 

      Åsvestad, Linn (Master thesis; Mastergradsoppgave, 2022-06-02)
      Passive Acoustic Monitoring (PAM) is a non-invasive method providing high- resolution information about marine mammal acoustic presence. Multi-species PAM studies can increase our understanding of temporal changes in species diversity and assemblage and is especially useful in remote areas such as the Southern Ocean. This study was based on 16 months of acoustic data spanning two austral autumns and ...
    • From Trash to Treasure: The use of Lumpfish (Cyclopterus lumpus) as feed for Red King Crab (Paralithodes camtschaticus) 

      Conradi-Larsen, Tora (Master thesis; Mastergradsoppgave, 2023-05-15)
      This thesis explores the potential of using farmed lumpfish (Cyclopterus lumpus), discarded from Atlantic salmon (Salmo salar L.) aquaculture industry, as a sustainable feed for juvenile red king crabs (Paralithodes camtschaticus). The red king crab has successfully established a self-sustaining population in the Barents Sea. With the red king crab being a large generalist predator, its impact on ...
    • Ingestion of Tyre Crumb Rubber and Uptake of Associated Contaminants in Marine Invertebrates (Pandalus borealis) and Fish (Cyclopterus lumpus) – An Experimental Exposure Study 

      Hägg, Fanny (Master thesis; Mastergradsoppgave, 2022-05-15)
      Crumb rubber (CR) produced from end of life vehicle tires is widely used on artificial sports fields and to create urban artificial surfaces. It is also used as a surrogate for tyre wear particles in experimental studies simulating the behaviour and effects of car tyre particles in the environment. It is known to contain a wide range of organic chemicals and metals, some of which are only just being ...
    • Aggregative response in white-tailed eagles- an initial study of the terrestrial implications of invasive Pacific pink salmons (Oncorhynchus gorbuscha) in northern Norway. 

      Bonde, Bror Mathias (Master thesis; Mastergradsoppgave, 2023-05-15)
      Abstract The spawning population of invasive Pacific pink salmon (Oncorhynchus gorbuscha) has only continued to increase in the river systems on the Varanger peninsula in Norway, causing concerns across institutional boundaries and management communities. So far, the Norwegian research efforts on Pacific pink salmon have been centred on consequential effects in marine- and freshwater ecosystems, ...
    • Exposure of marine invertebrates to car tire rubber: Uptake of rubber particles and related organic chemicals 

      Galtung, Kristin (Master thesis; Mastergradsoppgave, 2023-05-15)
      Car tire rubber particles (CTRPs) are a major source of microplastic pollution to the environment, originating from abrasion during driving or the use of crumb rubber granulates made of discarded tires. However, large knowledge gaps remain regarding the distribution and presence of CTRPs in marine environments and interaction with marine organisms. The aims of this thesis were to investigate the ...
    • Isolation and Characterization of Bacteriophages from the Arctic 

      Hosen, Md Sabuj (Master thesis; Mastergradsoppgave, 2023-05-14)
      Bacteriophages are viruses that specifically infect bacteria. These obligate intracellular parasites are Earth's most copious, ubiquitous, and genetically diverse (unexplored) biological entities. Organisms in the Arctic environment constantly experience extreme conditions, therefore life in the Arctic evolved different specialized strategies and molecules to survive which offers huge opportunities ...
    • The impact of advection on a Subarctic fjord food web dominated by the copepod Calanus finmarchicus 

      Basedow, Sünnje Linnéa; Renner, Angelika; Espinasse, Boris Dristan; Falk-Petersen, Stig; Graeve, Martin; Bandara, Kanchana; Sørensen, Kai; Eiane, Ketil; Hagen, Wilhelm (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-04)
      Fjord and shelf food webs are frequently supplemented by the advection of external biomass, which in high-latitude seas often comes in the form of lipid-rich copepods that can support a wide range of fish species, including Northeast Arctic cod (Gadus morhua). A seasonal match or mismatch at the lower trophic levels (phytoplankton and zooplankton) is central in determining how much energy and biomass ...
    • Habitat segregation by sympatric juvenile Arctic charr and brown trout in shallow lake areas: a consequence of interspecifc diferences in predator avoidance? 

      Svenning, Martin; Stien, Audun; Borgstrøm, Reidar (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-06)
      In sympatry, juvenile brown trout (Salmo trutta) usually occupy the shallow and most productive areas (littoral zone) of lakes, while juveniles of Arctic charr (Salvelinus alpinus) are found in deeper, less productive parts. In contrast, when Arctic charr juveniles occur in allopatry, they often occupy shallow littoral areas as well. Habitat segregation has traditionally been interpreted as a trade-of ...
    • Is the diet cyclic phase-dependent in boreal vole populations? 

      Neby, Magne; Ims, Rolf Anker; Kamenova, Stefaniya Kamenova; Devineau, Olivier; Soininen, Eeva Marjatta (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-04-17)
      Herbivorous rodents in boreal, alpine and arctic ecosystems are renowned for their multi-annual population cycles. Researchers have hypothesised that these cycles may result from herbivore–plant interactions in various ways. For instance, if the biomass of preferred food plants is reduced after a peak phase of a cycle, rodent diets can be expected to become dominated by less preferred food plants, ...
    • Synchronous timing of return to breedingsites in a long-distance migratory seabirdwith ocean-scale variation in migrationschedules 

      van Bemmelen, Rob S.A.; Moe, Børge; Schekkerman, Hans; Hanssen, Sveinn Are; Snell, Katherine R. S.; Humphreys, Elizabeth M.; Mäntylä, Elina; Hallgrimsson, Gunnar Thor; Gilg, Olivier; Ehrich, Dorothee; Calladine, John; Hammer, Sjúrður; Harris, Sarah; Lang, Johannes; Vignisson, Sölvi Rúnar; Kolbeinsson, Yann; Nuotio, Kimmo; Sillanpää, Matti; Sittler, Benoit; Sokolov, Aleksandr; Klaassen, Raymond H. G.; Phillips, Richard A.; Tulp, Ingrid (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-22)
      Background Migratory birds generally have tightly scheduled annual cycles, in which delays can have carry-over effects on the timing of later events, ultimately impacting reproductive output. Whether temporal carry-over effects are more pronounced among migrations over larger distances, with tighter schedules, is a largely unexplored question. <p><p>Methods We tracked individual Arctic Skuas ...
    • Sluttrapport for prosjekt: "Kartlegging og testing av metoder for å redusere interaksjoner mellom fiskeri og hval" - FHF 901681 

      Tenningen, Maria; Sivle, Lise Doksæter; Biuw, Martin; Rikardsen, Audun H. (Research report; Forskningsrapport, 2024-04-03)
      Spekkhoggere og knølhval i norske farvann følger den pelagiske fiskeflåten og beiter på fisken som blir samlet sammen av nøtene. Disse interaksjonene har ved flere anledninger ført til skade eller død av hval, og fangsttap og ødelagte redskap for fiskerne. Målsetningen i dette prosjektet var å kartlegge og teste utstyr og metoder som kan bidra til å redusere uønskede interaksjoner mellom spekkhoggere ...
    • Reindeer in the Arctic reduce sleep need during rumination 

      Furrer, Melanie; Meier, Sara A.; Jan, Maxime; Franken, Paul; Sundset, Monica Alterskjær; Brown, Steven A.; Wagner, Gabriela; Huber, Reto (Journal article; Tidsskriftartikkel, 2023-12-22)
      Timing and quantity of sleep depend on a circadian (ca 24-h) rhythm and a specific sleep requirement. Sleep curtailment results in a homeostatic rebound of more and deeper sleep, the latter reflected in increased electroencephalographic (EEG) slow-wave activity (SWA) during non-rapid eye movement (NREM) sleep. Circadian rhythms are synchronized by the light-dark cycle but persist under constant ...
    • Interannual differences in sea ice regime in the north-western Barents Sea cause major changes in summer pelagic production and export mechanisms 

      Amargant I Arumi, Marti; Müller, Oliver; Bodur, Yasemin Vicdan; Ntinou, Iliana Vasiliki; Vonnahme, Tobias; Assmy, Philipp Kurt Wolf; Kohlbach, Doreen; Chierici, Melissa; Jones, Elizabeth Marie; Olsen, Lasse Mork; Tsagaraki, Tatiana; Reigstad, Marit; Bratbak, Gunnar; Gradinger, Rolf Rudolf (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-22)
      The Barents Sea is a highly dynamic and productive marine ecosystem and a hotspot of global warming. Variability in sea ice extent is a common feature in the Barents Sea with substantial movements of the sea ice edge on short-term, seasonal to interannual time scales. Historically the northern Barents Sea (north of 75◦N) has been ice-covered in winter, but recently it has become the area with most ...
    • Can plastic related chemicals be indicators of plastic ingestion in an Arctic seabird? 

      Collard, France; Tulatz, Felix; Harju, Mikael; Herzke, Dorte; Bourgeon, Sophie; Gabrielsen, Geir Wing (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-22)
      For decades, the northern fulmar (Fulmarus glacialis) has been found to ingest and accumulate high loads of plastic due to its feeding ecology and digestive tract morphology. Plastic ingestion can lead to both physical and toxicological effects as ingested plastics can be a pathway for hazardous chemicals into seabirds' tissues. Many of these contaminants are ubiquitous in the environment and the ...
    • Diel activity rhythms in wild songbirds in the Subarctic 

      Staurland, Marie Østlid (Master thesis; Mastergradsoppgave, 2024-02-15)
      The highly rhythmic environment caused by the rotation of the earth has driven the evolution of an intrinsic timekeeping mechanism in most organisms known as circadian clocks. As climate change drives the expansion of southern species into northern latitudes, their circadian clocks are challenged by the novel light conditions they encounter. In contrast to the clear day and night in southern latitudes, ...
    • To keep or not to keep track of time in eternal sunshine? Diel activity patterns of Svalbard arthropods during polar day 

      Huntsaar, Maria (Master thesis; Mastergradsoppgave, 2024-02-16)
      Organisms on Earth are exposed to cyclic changes in environmental variables due to Earth’s rotation around it’s axis. As a response, many organisms adapt their behaviour in a rhythmic manner, which is often cued by 24h light-dark cycles. However, in the Arctic, traditional 24h light- dark cycle cues do not exist for long periods at the time. Arthropods play an important role in the high latitude ...
    • Long-term warming-induced trophic downgrading in the soil microbial food web 

      Dahl, Mathilde Borg; Söllinger, Andrea; Sigurðsson, Páll; Janssens, Ivan; Peñuelas, Josep; Sigurdsson, Bjarni D.; Richter, Andreas; Tveit, Alexander; Urich, Tim (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-05-01)
      Climatic warming has been hypothesized to accelerate organic matter decomposition by soil microorganisms and thereby enhance carbon (C) release to the atmosphere. However, the long-term consequences of soil warming on belowground biota interactions are poorly understood. Here we investigate how geothermal warming by 6 °C for more than 50 years affects soil microbiota. Using metatranscriptomics we ...
    • Norwegian killer whale movements reflect their different preytypes 

      Vogel, Emma Frances; Rikardsen, AH; Blanchet, Marie-Anne; Blévin, Pierre; Biuw, Martin (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-21)
      Norwegian killer whales (Orcinus orca) are thought to be generalists that feed primarily on fish, but some individuals have been observed targeting pinnipeds. In the study reported here, field observations of foraging behaviours formed the basis of a priori classification as either seal-eaters or fish-eaters. Concurrent collection of photographic identification and biopsies for stable isotope analysis ...