Blar i NIVA Open Access Archive på forfatter "Kristensen, Torstein"
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An acoustic sensor transmitter for in situ assessment of water quality and fish behaviour during chemical treatment of a parasite-infected river system: tag design and practical use
Alfredsen, Knut; Urke, Henning Andre; Kristensen, Torstein; Kvakland, Marte; Grønningsæter, Åge; Hagen, Anders Gjørwad; Alfredsen, Jo Arve (Peer reviewed; Journal article, 2021)Behaviour of potential host fish during chemical treatment against the ectoparasite Gyrodactylus salaris is a vital factor in designing treatment strategies, evaluating risk factors and establishing insights into previously ... -
Cardiac molecular-acclimation mechanisms in responseto swimming-induced exercise in atlantic salmon
Castro, Vicente; Grisdale-Helland, Barbara; Helland, Ståle; Torgersen, Jacob; Kristensen, Torstein; Claireaux, Guy; Farrell, Anthony P.; Takle, Harald Rune (Journal article; Peer reviewed, 2013)Cardiac muscle is a principal target organ for exercise-induced acclimation mechanisms in fish and mammals, given that sustained aerobic exercise training improves cardiac output. Yet, the molecular mechanisms underlying ... -
Diel migration pattern of Atlantic salmon (Salmo salar) and sea trout (Salmo trutta) smolts: an assessment of environmental cues
Haraldstad, Tormod; Kroglund, Frode; Kristensen, Torstein; Jonsson, Bror; Haugen, Thrond O (Journal article; Peer reviewed, 2017)The timing of smolt migration is a key phenological trait with profound implications for individual survival during both river descent and the subsequent sea sojourn of anadromous fish. We studied relationships between the ... -
Effects of mining chemicals on fish: exposure to tailings containing Lilaflot D817M induces CYP1A transcription in Atlantic salmon smolt
Olsvik, Pål A.; Urke, Henning A.; Nilsen, Tom O.; Ulvund, John B.; Kristensen, Torstein (Journal article; Peer reviewed, 2015)Background: Mine tailings, containing metals and production chemicals such as flotation chemicals and flocculants, may pose an environmental threat to aquatic organisms living in downstream ecosystems. The aim of this work ... -
Freshwater treatment of amoebic gill disease and sea-lice in seawater salmon production: considerations of water chemistry and fish welfare
Powell, Mark Darryn; Kristensen, Torstein (NIVA-rapport; 6632, Research report, 2014)Amoebic gill disease (AGD) and sea lice are two of the most significant disease issues facing the Norwegian Atlantic salmon aquaculture industry. Although both diseases respond to various extents, to freshwater treatment, ... -
Freshwater treatment of amoebic gill disease and sea-lice in seawater salmon production: Considerations of water chemistry and fish welfare in Norway
Powell, Mark Darryn; Reynolds, Patric; Kristensen, Torstein (Journal article; Peer reviewed, 2015)Amoebic gill disease (AGD) and sea lice are two of the most significant disease issues that the Norwegian Atlantic salmon aquaculture industry is facing. Although both diseases respond to various extents, to freshwater ... -
Konsekvenser av sjødeponi i Repparfjorden for anadrom laksefisk. Delutredning i KU program for planlagt gruvedrift i Nussir og Ulveryggen i Kvalsund kommune
Urke, Henning Andre; Kristensen, Torstein; Daae, Kjersti Lundmark; Bergan, Morten Andre; Ulvund, John Birger; Alfredsen, Jo Arve (NIVA-rapport;6176, Research report, 2011)Utredningen tar for seg mulige konsekvenser av sjødeponi for anadrom laksefisk i Repparfjorden basert på foreliggende grunnlagsundersøkelse og resultater fra andre delutredninger i henhold til planprogrammet. Laksesmolten ... -
Predicting the nationwide outmigration timing of Atlantic salmon (Salmo salar) smolts along 12 degrees of latitude in Norway
Vollset, Knut; Lennox, Robert J.; Lamberg, Anders; Skaala, Øystein; Sandvik, Anne Dagrun; Sægrov, Harald; Kvingedal, Eli; Kristensen, Torstein; Jensen, Arne Johan; Haraldstad, Tormod; Barlaup, Bjørn Torgeir; Ugedal, Ola (Peer reviewed; Journal article, 2021)Aim Accurate predictions about transition timing of salmon smolts between freshwater and marine environments are key to effective management. We aimed to use available data on Atlantic salmon smolt migration to predict the ... -
Reduced Acid Deposition Leads to a New Start for Brown Trout (Salmo trutta) in an Acidified Lake in Southern Norway
Lund, Espen; Garmo, Øyvind A; de Wit, Heleen A; Kristensen, Torstein; Hawley, Kate L; Wright, Richard F (Journal article; Peer reviewed, 2018)Acid deposition has led to acidification and loss of fish populations in thousands of lakes and streams in Norway. Since the peak in the late 1970s, acid deposition has been greatly reduced and acidified surface waters ... -
Sjøauren i Lærdalselva; vekstmønster og fjordvandringar før og no
Kristensen, Torstein; Urke, Henning A.; Haugen, Thrond O.; Rustadbakken, Atle; Alfredsen, Jo A.; Alfredsen, Knut; Rosseland, Bjørn O. (NIVA-rapport;6122, Research report, 2011)Forsknings- og utgreiingsarbeid knytt til behandlingar mot Gyrodactylus salaris i Lærdalselva har framskaffa interessante data på sjøaurestamma sin biologi. Telemetristudiar av vandringsåtferd i elv og fjord er gjennomførde. ... -
Sluttrapport - Artec pilot Dokumentasjon av vannkvalitet og fiskefysiologi i et pilotanlegg for resirkulering (Artec Pilot) og et gjennomstrømmingsanlegg
Hess-Erga, O.; Kristensen, Torstein; Eliassen, Robert; Iversen, Martin H. (NIVA-rapport;6281, Research report, 2012)Sett under ett viser forsøkene at Resirkuleringssystemet (Artec Pilot) kan benyttes til kommersiell smoltproduksjon på lik linje med tradisjonelt gjennomstrømmingssystem. Ved optimal drift vil også fiskevelferden bli godt ...