Viser treff 1421-1440 av 2078

    • DNA barcoding of the northern Northeast Atlantic skates (Chondrichthyes, Rajiformes), with remarks on the widely distributed starry ray 

      Lynghammar, Arve; Christiansen, Jørgen Schou; Griffiths, Andrew M.; Fevolden, Svein-Erik; Hop, Haakon; Bakken, Torkild (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-06-23)
      The skate fauna in the northern Northeast (NE) Atlantic is poorly investigated, and misidentifications are common. Here, ‘DNA barcoding’ was used to analyse 105 specimens of 15 species previously reported from the area to investigate the occurrence of species. Of these 15 species, three were new to the region and confirmed with voucher specimens. Three previously reported taxa were not obtained from ...
    • Transmission dynamics of the monogenean Gyrodactylus salaris under seminatural conditions 

      Hendrichsen, Ditte Katrine; Kristoffersen, Roar; Gjelland, Karl Øystein; Knudsen, Rune; Kusterle, Stefan; Rikardsen, Audun H.; Henriksen, Eirik Haugstvedt; Smalås, Aslak; Olstad, Kjetil (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-07-12)
      Tracking individual variation in the dynamics of parasite infections in wild populations is often complicated by lack of knowledge of the epidemiological history of hosts. Whereas the dynamics and development of Gyrodactylus salaris Malmberg, 1957, on Atlantic salmon, Salmo salar L., are known from laboratory studies, knowledge about infection development on individual wild fishes is currently sparse. ...
    • Comparative life cycle assessment of tailings management and energy scenarios for a copper ore mine: A case study in Northern Norway 

      Song, Xingqiang; Pettersen, Johan Berg; Pedersen, Kristine Bondo; Røberg, Stian (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-07-05)
      In support of continuous environmental improvement in the mining industry, it is important to systematically assess the environmental impacts of mining and mineral processing operations from a life cycle perspective. Although life cycle assessment (LCA) is widely used as an environmental systems analysis tool, the application of LCA in the mining industry is still in progress. This paper carried ...
    • Parasite communities of two three-spined stickleback populations in subarctic Norway—effects of a small spatial-scale host introduction 

      Kuhn, Jesper Andreas; Kristoffersen, Roar; Knudsen, Rune; Jakobsen, Jonas; Marcogliese, D. J.; Locke, S. A.; Primicerio, Raul; Amundsen, Per-Arne (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-01-30)
      We compared metazoan parasite communities of an introduced three-spined stickleback (Gasterosteus aculeatus) population with the nearby source population in northern Norway to study differences and clarify if factors controlling parasite dispersal act on a small spatialscale. The two component communities were highly similar. All parasite taxa found in the source population also occurred in the ...
    • Risk assessment of marking and tracing methods with regards to the welfare of farmed salmonids. Opinion of the Panel on Animal Health and Welfare of the Norwegian Scientific Committee for Food Safety 

      Mortensen, Stein; Kristiansen, Tore S; Mejdell, Cecilie Marie; Uglem, Ingebrigt; Agdestein, Angelika; Basic, Dean; Bergh, Øivind; Brun, Edgar; Bøe, Knut Egil; Das Neves, Carlos G; Godfroid, Jacques; Gudding, Roar; Hoel, Kristian; Rimstad, Espen; Hjeltnes, Brit (Research report; Forskningsrapport, 2016-12-15)
    • Temporal changes and between-host variation in the intestinal parasite community of Arctic charr in a subarctic lake 

      Kuhn, Jesper A.; Knudsen, Rune; Kristoffersen, Roar; Primicerio, Raul; Amundsen, Per-Arne (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-03-16)
      The occurrence of trophically transmitted intestinal parasites in Arctic charr was analyzed from data material collected over two decades from Lake Takvatn, northern Norway. The main objectives were to investigate (i) between-year variation in parasite infracommunity composition, (ii) between-host variation in infracommunity composition, and (iii) possible interspecific interaction between parasites. ...
    • Effects of fish species composition on Diphyllobothrium spp. infections in subarctic brown trout - is three-spined stickleback a key species? 

      Kuhn, Jesper A.; Frainer, André; Knudsen, Rune; Kristoffersen, Roar; Amundsen, Per-Arne (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-04-25)
      Subarctic populations of brown trout (Salmo trutta) are often heavily infected with cestodes of the genus Diphyllobothrium, assumedly because of their piscivorous behavior. This study explores possible associations between availability of fish prey and Diphyllobothrium spp. infections in lacustrine trout populations. Trout in i) allopatry (group T); ii) sympatry with Arctic charr (Salvelinus alpinus) ...
    • Trophic ecology of brown trout (Salmo trutta L.) in subarctic lakes 

      Sanchez-Hernandez, Javier; Amundsen, Per-Arne (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-04-29)
      In subarctic lake systems, fish species like brown trout are often important predators, and their niche performance is a key characteristic for understanding trophic interactions and food web functioning at upper trophic levels. Here, we studied summer habitat use and stomach contents of brown trout under both allopatric and sympatric conditions in six subarctic lakes to reveal its trophic role, and ...
    • Return migration of adult Atlantic salmon (Salmo salar L.) to northern Norway 

      Ulvan, Eva Marita; Foldvik, Anders; Jensen, Arne Johan; Finstad, Bengt; Thorstad, Eva Bonsak; Rikardsen, Audun H.; Næsje, Tor (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-09-18)
      The return migration of adult Atlantic salmon was investigated by analysing recaptures of individuals tagged and released as smolts in the River Altaelva and the River Halselva using a catch per unit effort approach. Although the salmon were recaptured over a large area along the coastline (from >1100 km south to>500 km northeast of their home rivers), the results indicated a relatively accurate ...
    • Food/feed and environmental risk assessment of insect-resistant and herbicide-tolerant genetically modified maize 59122 x 1507 x NK603 for food and feed uses, import and processing under Regulation (EC) No 1829/2003 (EFSA/GMO/UK/2005/21). Opinion of the Panel on Genetically Modified Organisms of the Norwegian Scientific Committee for Food Safety 

      Andreassen, Åshild Kristine; Brandtzæg, Per; Sorteberg, Hilde-Gunn Opsahl; Holck, Askild Lorentz; Junttila, Olavi; Konestabo, Heidi Sjursen; Meadow, Richard; Nielsen, Kaare Magne; Vikse, Rose (Research report; Forskningsrapport, 2013-10-21)
      In preparation for a legal implementation of EU-regulation 1829/2003, the Norwegian Scientific Committee for Food Safety (VKM) has been requested by the Norwegian Environment Agency (former Norwegian Directorate for Nature Management) and the Norwegian Food Safety Authority (NFSA) to conduct final food/feed and environmental risk assessments for all genetically modified organisms (GMOs) and ...
    • Gjenfangst av laks (Salmo salar L.) etter fang og slipp-praksis i norske elver 

      Johansen, Martin Rognli (Master thesis; Mastergradsoppgave, 2017-05-18)
      Som følge av at norske laksebestander har blitt redusert i løpet av de siste tiårene har det blitt vanligere å gjenutsette laks i forbindelse med sportsfiske. Noen av disse gjenutsatte laksene er rapportert å gjenfanges, men omfanget av dette har hittil ikke vært dokumentert i detalj i norske elver. Slik gjenfangst kan tenkes å beskatte forskjellige deler av en populasjon ulikt, være problematisk i ...
    • Haul-out behaviour of walruses (Odobenus rosmarus) monitored by camera stations - potential impacts of tourist visitations 

      Øren, Kine (Master thesis; Mastergradsoppgave, 2017-05-16)
      The rapid growth of tourism in Polar Regions stimulates a need for investigating potential impacts on targeted species and sensitive areas, such as walrus (Odobenus rosmarus) haul-out sites. This study examines effects of tourist visitations on haul-out dynamics and site use by walruses in Svalbard, Norway. Camera stations were established at five traditional walrus haul-out sites that experience ...
    • Spawning behavior of Arctic charr (Salvelinus alpinus): spawning synchrony, vibrational communication and mate guarding. 

      Brattli, Magnus Beyer (Master thesis; Mastergradsoppgave, 2017-05-15)
      A mismatch between male and female gamete release can result in reduced or failed fertilization in external fertilizers, sperm competition and reduced paternity. Here, I video monitored spawning behavior of free living Arctic charr (Salvelinus alpinus), and analyzed details of their reproductive biology. In total, 157 spawnings were recorded. Females clearly preferred spawning with the dominant male, ...
    • Strategies for timing of nest departure in the common guillemot Uria aalge 

      Johansen, Malin Kjellstadli (Master thesis; Mastergradsoppgave, 2017-05-15)
      Duration of parental care in avian species varies widely, from altricial to precocial species. The seabird family Alcidae is unique among birds in the variation of mass and age at nest departure. The common guillemot Uria aalge exhibits an intermediate nest departure, where chicks leave the nest flightless and only at a quarter of adult body size. The aim of this study was to examine factors controlling ...
    • An empirical analysis of cultural ecosystem values in coastal landscapes 

      Brown, Greg; Hausner, Vera Helene (Journal article; Tidsskriftartikkel, 2017)
      Coastal areas are especially important to human well-being with half the world's population living within 60 km of the sea and three-quarters of all large cities located in the coastal zone. Supporting and regulatory ecosystem services in coastal areas have received considerable research attention given human vulnerability to climate change, but cultural ecosystem services in the coastal zone are ...
    • Effects of exhaustive swimming and subsequent recuperation on flesh quality in unstressed Atlantic cod (Gadus morhua) 

      Svalheim, Ragnhild Aven; Karlsson-Drangsholt, Anders; Olsen, Stein Harris; Johnsen, Helge K.; Aas-Hansen, Øyvind (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-25)
      Wild Atlantic cod of commercial size (1.9 ± 0.5 kg) were swum to exhaustion in a large swim tunnel in an attempt to mimic the initial stage of trawling, when fish swim at the trawl mouth until they fatigue or lose interest and subsequently drop into the trawl. The objective of the study was to investigate if exhaustive swimming in unstressed cod had any negative effects on fillet quality, and if ...
    • CRISPR/Cas9—Advancing Orthopoxvirus Genome Editing for Vaccine and Vector Development 

      Okoli, Arinze Stanley; Okeke, malachy ifeanyi; Tryland, Morten; Moens, Ugo (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-01-22)
      : The clustered regularly interspaced short palindromic repeat (CRISPR)/associated protein 9 (Cas9) technology is revolutionizing genome editing approaches. Its high efficiency, specificity, versatility, flexibility, simplicity and low cost have made the CRISPR/Cas9 system preferable to other guided site-specific nuclease-based systems such as TALENs (Transcription Activator-like Effector ...
    • Brucella antibodies in alaskan true seals and eared seals — two different stories 

      Nymo, Ingebjørg H.; Rødven, Rolf; Beckmen, Kimberlee; Larsen, Anett K.; Tryland, Morten; Quakenbush, Lori; Godfroid, Jacques (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-01-31)
      Brucella pinnipedialis was first isolated from true seals in 1994 and from eared seals in 2008. Although few pathological findings have been associated with infection in true seals, reproductive pathology including abortions, and the isolation of the zoonotic strain type 27 have been documented in eared seals. <br> In this study, a Brucella enzyme-linked immunosorbent assay (ELISA) and the Rose ...
    • Estimating population trends of a riparian bird community in low-Arctic tundra. 

      Koren, Clémence (Master thesis; Mastergradsoppgave, 2018-02-15)
      In the Northern Norway tundra, willow thicket along river valleys create a more productive environment than the surrounding open tundra and host a rich community of bird species by providing food, shelter from predators and nesting site. The state of Arctic ecosystem is expected to undergo long-term changes due to opposite effects of climate change and herbivory pressure. It is also the background ...
    • Nutrients vs. turbulence, and the future of Arctic Ocean primary production 

      Randelhoff, Achim; Sundfjord, Arild; Fer, Ilker; Reigstad, Marit; Tremblay, Jean-Eric; Guthrie, John D. (Conference object; Konferansebidrag, 2016-11)
      This poster presents estimates of nitrate fluxes in the Arctic Ocean and speculates on the associated primary production in a future climate.