Blar i Brage IMR på forfatter "Ottersen, Geir"

Viser treff 21-40 av 76

    • Diets of the Barents Sea cod (Gadus morhua) from the 1930s to 2018 

      Townhill, Bryony; Holt, Rebecca Emma; Bogstad, Bjarte; Durant, Jo l M.; Pinnegar, John K.; Dolgov, Andrey V.; Yaragina, Natalia A.; Johannesen, Edda; Ottersen, Geir (Peer reviewed; Journal article, 2021)
      A new dataset on the diet of Atlantic cod in the Barents Sea from the 1930s to the present day has been compiled to produce one of the largest fish diet datasets available globally. Atlantic cod is one of the most ecologically ...

    • Direct and indirect climate forcing in a multi-species marine system 

      Ottersen, Geir; Stige, Leif Christian; Dalpadado, Padmini; Chan, Kung-Sik; Hjermann, Dag Ø.; Lajus, Dmitry L.; Yaragina, Natalia A.; Stenseth, Nils Christian (Journal article; Peer reviewed, 2010-10)
      Interactions within and between species complicate quantification of climate effects, by causing indirect, often delayed, effects of climate fluctuations and compensation of mortality. Here we identify direct and indirect ...

    • Do abiotic mechanisms determine interannual variability in length-at-age of juvenile Arcto-Norwegian cod? 

      Ottersen, Geir; Helle, Kristin; Bogstad, Bjarte (Journal article; Peer reviewed, 2002)
      For the large Arcto-Norwegian stock of cod (Gadus morhua L.) in the Barents Sea, year-to-year variability in growth is well documented. Here three hypotheses for the observed inverse relation between abundance and the mean ...

    • Dramatic changes in spawning stock age-structure of Barents Sea cod 

      Ottersen, Geir; Hjermann, Dag Ø.; Stenseth, Nils Christian (ICES CM documents, Working paper, 2004)
      Atlantic Cod (Gadus morhua) is one of the commercially most important fish species in the North Atlantic and plays a central role in several ecosystems. Fishing pressure has been heavy over a prolonged period and the ...

    • Effekter på økosystemer og biologisk mangfold : Klimaendringer i norsk Arktis : NorACIA delutredning 3 

      Loeng, Harald; Ottersen, Geir; Svenning, Martin A.; Stien, Audun (Research report, 2010-02)

    • Enhancing stock-recruitment models for North Sea cod by including climate and zooplankton 

      Ottersen, Geir; Olsen, Esben Moland; Stenseth, Nils Christian (ICES CM documents;2009/C:08, Working paper, 2009)
      The “recruitment problem” - trying to understand what regulates recruitment variability in marine fish populations - has been the number one issue in fisheries science since the early twentieth century. Intuitively, the ...

    • Environmental benefits of leaving offshore infrastructure in the ocean 

      Fowler, Ashley M.; Jørgensen, Anne-Mette; Svendsen, Jon C.; Macreadie, Peter I.; Jones, Daniel O.B.; Boon, Arjen R.; Booth, David J.; Brabant, Robin; Callahan, Emily; Claisse, Jeremy T.; Dahlgren, Thomas G.; Degraer, Steven; Dokken, Quenton R.; Gill, Andrew B.; Johns, David G.; Leewis, Robert J.; Lindeboom, Han J.; Linden, Olof; May, Roelof Frans; Murk, Albertinka J.; Ottersen, Geir; Schroeder, Donna M.; Shastri, Sunil M.; Teilmann, Jonas; Todd, Victoria; Hoey, Gert Van; Vanaverbeke, Jan; Coolen, Joop W.P. (Peer reviewed; Journal article, 2018)
      The removal of thousands of structures associated with oil and gas development from the world’s oceans is well underway, yet the environmental impacts of this decommissioning practice remain unknown. Similar impacts will ...

    • Environmental toxicology: Population modeling of cod larvae shows high sensitivity to loss of zooplankton prey 

      Stige, Leif Christian; Ottersen, Geir; Hjermann, Dag Ø.; Dalpadado, Padmini; Jensen, Louise K.; Stenseth, Nils Christian (Journal article; Peer reviewed, 2010-12-30)
      Two factors determine whether pollution is likely to affect a population indirectly through loss of prey: firstly, the sensitivity of the prey to the pollutants, and secondly, the sensitivity of the predator population to ...

    • Environmental toxicology: Population modeling of cod larvae shows high sensitivity to loss of zooplankton prey 

      Stige, Leif Christian; Ottersen, Geir; Hjermann, Dag Ø.; Dalpadado, Padmini; Jensen, Louise K.; Stenseth, Nils Christian (Journal article; Peer reviewed, 2010-12-30)
      Two factors determine whether pollution is likely to affect a population indirectly through loss of prey: firstly, the sensitivity of the prey to the pollutants, and secondly, the sensitivity of the predator population to ...

    • Erfaringer fra et tiår med forvaltningsplanarbeid i Norge og utfordringer fremover 

      van der Meeren, Gro; Arneberg, Per; Ottersen, Geir; Storeng, Anne Britt (Rapport fra Havforskningen;4-2015, Working paper, 2015-06)

    • Et digitalt temperaturatlas for Norskehavet 

      Ottersen, Geir (Fisken og havet, Research report, 2009)
      A digital temperature archive for the Norwegian Sea compiled from 59496 temperature profiles is presented. It consists of interpolated temperature fields for the quarters January-March, April-June, July-September, and ...

    • An evaluation of recruitment indices for Northeast Arctic cod (Gadus morhua L.) 

      Helle, Kristin; Bogstad, Bjarte; Marshall, C. Tara; Michalsen, Kathrine; Ottersen, Geir; Pennington, Michael (ICES CM documents, Working paper, 1999)
      Indices of the abundance of Northeast Arctic cod (Gadus morhua L.) for various life stages were compared in order to determine the earliest stage at .which year-class strength is established. The indices considered are: ...

    • Faglig grunnlag for en forvaltningsplan for Nordsjøen og Skagerrak: Arealrapport 

      Ottersen, Geir; Postmyr, Egil; Irgens, Magnus (Fisken og havet;6-2010, Research report, 2010-06-25)
      Arealrapporten gir en omfattende beskrivelse av havområdets miljø, ressurser og forurensningssituasjon. Rapporten identifiserer særlig verdifulle områder, og det gis en generell og foreløpig vurdering av områdenes sårbarhet. ...

    • Fish and oil in the Lofoten–Barents Sea system: synoptic review of the effect of oil spills on fish populations 

      Hjermann, Dag Ø.; Melsom, Arne; Dingsør, Gjert Endre; Durant, Joël M.; Eikeset, Anne Maria; Røed, Lars Petter; Ottersen, Geir; Storvik, Geir; Stenseth, Nils Christian (Journal article; Peer reviewed, 2007-06-06)
      The Lofoten-Barents Sea area, which contains some of the most valuable fish stocks of the Atlantic Ocean, is being considered for offshore oil production. We review the effects of a hypothetical oil spill on fishes in this ...

    • Forvaltningsplan Barenshavet – rapport fra overvåkingsgruppen 2014 

      Havforskningsinstituttet (Fisken og Havet, særnummer;1b-2014, Research report, 2014-06-05)

    • Forvaltningsplan Norskehavet - rapport fra overvåkingsgruppen 2013 

      Arneberg, P.; Ottersen, Geir; Frie, Anne Kirstine; van der Meeren, Gro; Johansson, Josefina; Selvik, Ingunn (Fisken og Havet, særnummer;1b-2013, Research report, 2013-02-15)

    • Growth of northeast arctic cod in relation to ambient temperature 

      Michalsen, Kathrine; Ottersen, Geir; Nakken, Odd (ICES CM documents, Working paper, 1996)
      In the present study temperature related changes in horizontal distribution are described and the influence of temperature on the growth of Northeast Arctic cod is interpreted. Data from acoustic-and bottom trawl surveys ...

    • Havforskningsrapporten 2011 : Ressurser, miljø og akvakultur på kysten og i havet 

      Agnalt, Ann-Lisbeth; Fossum, Petter; Hauge, Marie; Mangor-Jensen, Anders; Ottersen, Geir; Røttingen, Ingolf; Sundet, Jan H.; Sunnset, Beate Hoddevik (Fisken og havet, særnummer;1-2011, Research report, 2011-03)

    • Helhetlig forvaltningsplan for Norskehavet: arealrapport med miljø- og naturressursbeskrivelse 

      Ottersen, Geir; Auran, Jo Anders (Fisken og havet, Research report, 2007)
      The norwegian government has initiated a provess towards an integrated management plan for the Norwegian Sea. This report constitutes an important part of the description of underlying facts and knowledge and includes: a. ...

    • Hydrografisk variabilitet i tid og rom i Skagerrak 

      Ottersen, Geir; Søiland, Henrik; Svendsen, Einar; Danielssen, Didrik S. (Fisken og havet, Research report, 2003)
      This report addresses the tempora1 and spatial variability in the hydrography of the Skagerrak by means of statistical investigations including frequency analyses and spatial correlations. The analysis is based on the fixed ...