Blar i Scientific publications på forfatter "Jensen, Arne Johan"
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Contemporary ocean warming and freshwater conditions are related to later sea age at maturity in Atlantic salmon spawning in Norwegian rivers
Villar, Jaime Otero; Jensen, Arne Johan; Stenseth, Nils Christian; Storvik, Geir Olve; Vøllestad, Leif Asbjørn; L'Abée Lund, Henning (Journal article; Peer reviewed, 2012)Atlantic salmon populations are reported to be declining throughout its range, raising major management concerns. Variation in adult fish abundance may be due to variation in survival, growth, and timing of life history ... -
Escaped farmed Atlantic salmon grow, migrate and disperse throughout the Arctic Ocean like wild salmon
Jensen, Arne Johan; Karlsson, Sten; Fiske, Peder; Hansen, Lars Petter; Hindar, Kjetil; Østborg, Gunnel Marie (Peer reviewed; Journal article, 2013)This paper describes the first observations of escaped farmed Atlantic salmon Salmo salar in the Arctic Ocean. Among 138 individuals of Atlantic salmon captured at the west coast of the Spitsbergen Island at Svalbard in ... -
Evaluation of genetic effects on wild salmon populations from stock enhancement
Hagen, Ingerid Julie; Ugedal, Ola; Jensen, Arne Johan; Lo, Håvard; Holthe, Espen; Bjøru, Bjørn; Florø-Larsen, Bjørn; Sægrov, Harald; Skoglund, Helge; Karlsson, Sten (Peer reviewed; Journal article, 2020)Many salmonid populations are of conservation concern, and the release of hatchery-produced juveniles is a frequently used measure to alleviate declines and increase harvest opportunities. While such releases may be of ... -
Evidence for the linkage of survival of anadromous Arctic char and brown trout during winter to marine growth during the previous summer
Jensen, Arne Johan; Finstad, Bengt; Fiske, Peder (Journal article; Peer reviewed, 2017) -
Gene flow from domesticated escapes alters thelife history of wild Atlantic salmon
Bolstad, Geir Hysing; Hindar, Kjetil; Robertsen, Grethe; Jonsson, Bror; Sægrov, Harald; Diserud, Ola Håvard; Fiske, Peder; Jensen, Arne Johan; Urdal, Kurt; Næsje, Tor; Barlaup, Bjørn Torgeir; Florø-Larsen, Bjørn; Lo, Håvard; Niemela, Eero; Karlsson, Sten (Journal article, 2017)Interbreeding between domesticated and wild animals occurs in several species. This gene flow has long been anticipated to induce genetic changes in life-history traits of wild populations, thereby influencing population ... -
High prevalence of vaterite in sagittal otoliths causes hearing impairment in farmed fish
Reimer, T.; Dempster, T.; Warren-Myers, F.; Jensen, Arne Johan; Swearer, S.E. (Peer reviewed; Journal article, 2016) -
Introgression from farmed escapees affects the full life cycle of wild Atlantic salmon
Bolstad, Geir Hysing; Karlsson, Sten; Hagen, Ingerid Julie; Fiske, Peder; Urdal, Kurt; Sægrov, Harald; Florø-Larsen, Bjørn; Sollien, Vegard Pedersen; Østborg, Gunnel Marie; Diserud, Ola Håvard; Jensen, Arne Johan; Hindar, Kjetil (Peer reviewed; Journal article, 2021)After a half a century of salmon farming, we have yet to understand how the influx of genes from farmed escapees affects the full life history of Atlantic salmon (Salmo salar L.) in the wild. Using scale samples of over ... -
Rapid evolution of genetic and phenotypic divergence in Atlantic salmon following the colonisation of two new branches of a watercourse
Jensen, Arne Johan; Hansen, Lars Petter; Johnsen, Bjørn Ove; Karlsson, Sten (Journal article; Peer reviewed, 2017)Background: Selection acts strongly on individuals that colonise a habitat and have phenotypic traits that deviate from the local optima. Our objective was to investigate the evolutionary rates in Atlantic salmon (Salmo ... -
Relationship between marine growth and sea survival of two anadromous salmonid fish species
Jensen, Arne Johan; Finstad, Bengt; Fiske, Peder; Forseth, Torbjørn; Rikardsen, Audun H.; Ugedal, Ola (Journal article; Peer reviewed, 2017)This study found empirical evidence supporting the “growth–survival” paradigm in the marine phase of Arctic char (Salvelinus alpinus) and brown trout (Salmo trutta). The paradigm postulates that larger or faster-growing ... -
Repeatable individual variation in migration timing in two anadromous salmonids and ecological consequences
Jensen, Arne Johan; Finstad, Bengt; Fiske, Peder; Diserud, Ola Håvard; Thorstad, Eva Bonsak (Peer reviewed; Journal article, 2020)Consistent individual differences in behavior have been demonstrated for many animals, but there are few studies of consequences of such repeated behavior in the wild. We tested consistency in migration timing to and from ... -
Salmon louse infestation in wild brown trout populations generates multi-modal mixture distributions
Diserud, Ola Håvard; Hedger, Richard David; Finstad, Bengt; Hendrichsen, Ditte Katrine; Jensen, Arne Johan; Ugedal, Ola (Peer reviewed; Journal article, 2020)For successful evaluation of the overall effects of salmon louse infestation on brown trout population dynamics, it is crucial to have a realistic understanding of how lice infestation distributions are generated and how ... -
Stable isotope marking of otoliths duringvaccination: a novel method for mass-marking fish
Warren-Myers, Fletcher; Dempster, Tim; Fjelldal, Per Gunnar; Hansen, Tom; Jensen, Arne Johan; Swearer, Stephen E. (Peer reviewed; Journal article, 2014)Tagging or marking of fishes enables the collection of population-based information for ecological research, yet few techniques enable 100% mark detection success. We tested a new mass-marking technique: otolith marking ... -
Supplementary stocking selects for domesticated genotypes
Hagen, Ingerid Julie; Jensen, Arne Johan; Bolstad, Geir Hysing; Diserud, Ola Håvard; Hindar, Kjetil; Lo, Håvard; Karlsson, Sten (Journal article; Peer reviewed, 2019)Stocking of hatchery produced fish is common practise to mitigate declines in natural populations and may have unwanted genetic consequences. Here we describe a novel phenomenon arising where broodstock used for stocking ... -
The cost of anadromy: marine and freshwater mortality rates in anadromous Arctic char and brown trout in the Arctic region of Norway
Jensen, Arne Johan; Finstad, Bengt; Fiske, Peder (Peer reviewed; Journal article, 2019)It is hypothesized that in diadromous fish, migrations may occur because of differences in the availability of food in marine and freshwater habitats. The benefits of migration to sea may be increased growth opportunities ...