Blar i Brage IMR på forfatter "Skjæraasen, Jon Egil"
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Synergies between climate and management for Atlantic cod fisheries at high latitudes
Kjesbu, Olav Sigurd; Bogstad, Bjarte; Devine, Jennifer A.; Gjøsæter, Harald; Howell, Daniel; Ingvaldsen, Randi; Nash, Richard D.M.; Skjæraasen, Jon Egil (Journal article; Peer reviewed, 2014-02-18)The widespread depletion of commercially exploited marine living resources is often seen as a general failure of management and results in criticism of contemporary management procedures. When populations show dramatic and ... -
Terrestrial fatty acids from feed oil in feed for farmed salmonids are transferred to the liver, gonads, and muscle of wild Atlantic cod (Gadus morhua)
Meier, Sonnich; van der Meeren, Terje; Skjæraasen, Jon Egil; Bannister, Raymond; Rasinger, Josef; Karlsen, Ørjan (Peer reviewed; Journal article, 2023)Wild fish attracted to salmon farms feed on waste feed that presently contain high levels of fatty acids of terrestrial origin. This study examines whether mature Atlantic cod (Gadus morhua) caught at spawning grounds has ... -
Timecourse of oocyte development in saithe Pollachius virens
Skjæraasen, Jon Egil; Devine, Jennifer Ann; Godiksen, Jane Aanestad; Fonn, Merete; Otterå, Håkon Magne; Kjesbu, Olav Sigurd; Norberg, Birgitta; Langangen, Øystein; Karlsen, Ørjan (Journal article; Peer reviewed, 2017)Wild caught North Sea saithe Pollachius virens were monitored for growth, sex steroid profiles and oocyte development pre-spawning and measured for egg size and group fecundity during the spawning season in the laboratory. ... -
Timing and determination of potential fecundity in Atlantic cod (Gadus morhua)
Skjæraasen, Jon Egil; Nilsen, Trygve; Kjesbu, Olav Sigurd (Journal article; Peer reviewed, 2005)Studies using annual averages of lipid storage or estimated quality of the feeding season have shown that energy reserves influence egg production in Atlantic cod (Gadus morhua). However, vitellogenesis starts months ... -
Trade-offs between growth and reproduction in wild Atlantic cod
Folkvord, Arild; Jørgensen, Christian; Korsbrekke, Knut; Nash, Richard D.M.; Nilsen, Trygve; Skjæraasen, Jon Egil (Journal article; Peer reviewed, 2014-04-08)Animals partition and trade off their resources between competing needs such as growth, maintenance, and reproduction. Over a lifetime, allocation strategies should result in distinct trajectories for growth, survival, and ... -
Triploid Atlantic salmon and triploid Atlantic salmon × brown trout hybrids have better freshwater and early seawater growth than diploid counterparts
Fraser, Thomas; Lerøy, Hilde; Hansen, Tom Johnny; Skjæraasen, Jon Egil; Tronci, Valentina; Pinto Pedrosa, Cindy; Fjelldal, Per Gunnar; Nilsen, Tom Ole (Peer reviewed; Journal article, 2021)The use of reproductively sterile triploid salmonids would enhance the environmental sustainability of the aquaculture industry by preventing genetic exchange between escapees and wild conspecifics. To this end, we assessed ... -
Vertical dynamics and reproductive behaviour of farmed and wild Atlantic cod Gadus morhua
Meager, Justin J.; Skjæraasen, Jon Egil; Fernö, Anders; Karlsen, Ørjan; Løkkeborg, Svein; Michalsen, Kathrine; Utskot, Stig Ove (Journal article; Peer reviewed, 2009-09-04)Rapid development of fish mariculture and efforts to restock depleted populations have raised concerns about the effects on wild populations and the risk of genetic introgression from hybridisation. Reproduction of many ... -
Vertical dynamics and reproductive behaviour of farmed and wild Atlantic cod Gadus morhua
Meager, Justin J.; Skjæraasen, Jon Egil; Fernö, Anders; Karlsen, Ørjan; Løkkeborg, Svein; Michalsen, Kathrine; Utskot, Stig Ove (Journal article; Peer reviewed, 2009-09-04)Rapid development of fish mariculture and efforts to restock depleted populations have raised concerns about the effects on wild populations and the risk of genetic introgression from hybridisation. Reproduction of many ... -
Vertical dynamics and reproductive behaviour of farmed and wild Atlantic cod Gadus morhua
Meager, Justin J.; Skjæraasen, Jon Egil; Fernö, Anders; Karlsen, Ørjan; Løkkeborg, Svein; Michalsen, Kathrine; Utskot, Stig Ove (Journal article; Peer reviewed, 2009-09-04)Rapid development of fish mariculture and efforts to restock depleted populations have raised concerns about the effects on wild populations and the risk of genetic introgression from hybridisation. Reproduction of many ...