Browsing NIVA Open Access Archive by Author "Haugen, Thrond Oddvar"
Now showing items 1-9 of 9
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Anthropogenic and natural size-related selection act in concert during brown trout (Salmo trutta) smolt river descent
Haraldstad, Tormod; Höglund, Erik; Kroglund, Frode; Olsen, Esben Moland; Hawley, Kate Louise; Haugen, Thrond Oddvar (Peer reviewed; Journal article, 2020)By hindering migration and inducing direct turbine mortality during downstream migration, hydropower is regarded as one of the most serious threats to anadromous salmonids. Yet, little attention has been paid to long-term ... -
Behavioural response of brown trout (Salmo trutta) to total dissolved gas supersaturation in a regulated river
Lennox, Robert J.; Thiemer, Kirstine; Vollset, Knut Wiik; Pulg, Ulrich; Stranzl, Sebastian; Nilsen, Cecilie Iden; Haugen, Thrond Oddvar; Velle, Gaute (Peer reviewed; Journal article, 2021)Total dissolved gas supersaturation from dams and power stations is a chronic freshwater pollutant that is toxic to animals with aquatic respiration. Laboratory ecotoxicology experiments have revealed capacity for captive ... -
Forhold for overlevelse av Gyrodactylus salaris i Oslofjorden
Staalstrøm, Andre; Christensen, Guttorm; Haugen, Thrond Oddvar (NIVA-rapport;7814-2023, Research report, 2023)I denne rapporten har modellkjøringer med FjordOs-modellen blitt kalibrert mot målinger av saltholdighet i overflatelaget i Oslofjorden. Disse modellresultatene er brukt for å vurdere muligheten for at vandrende laks kan ... -
Hydropower-induced selection of behavioural traits in Atlantic salmon (Salmo salar)
Haraldstad, Tormod; Haugen, Thrond Oddvar; Olsen, Esben M.; Forseth, Torbjørn; Höglund, Erik (Peer reviewed; Journal article, 2021)Renewable energy projects such as hydropower facilities contribute towards meeting the world`s growing energy demands and urgent need for mitigating climate change. However, such infrastructure has the potential to ... -
Increased precision of growth data gained by reading multiple scales from each individual of Atlantic salmon (Salmo salar)
Haraldstad, Tormod; Haugen, Thrond Oddvar; Borgstrøm, Reidar; Jonsson, Bror (Journal article; Peer reviewed, 2016)The precision of growth estimates based on fish scales often remains uncertain because of withinindividual variation in scale size and scale patterns, and also due to measurement errors. Based on scale readings of Atlantic ... -
Influence of dense macrophyte vegetation and total gas saturation on the performance of acoustic telemetry
Thiemer, Kirstine; Lennox, Robert; Haugen, Thrond Oddvar (Peer reviewed; Journal article, 2022)Acoustic telemetry is widely used as a method for high resolution monitoring of aquatic animal movement to investigate relationships between individual animals and their environment. In shallow freshwater ecosystem, aquatic ... -
Migratory passage structures at hydropower plants as potential physiological and behavioural selective agents
Haraldstad, Tormod; Haugen, Thrond Oddvar; Kroglund, Frode; Olsen, Esben Moland; Höglund, Erik (Peer reviewed; Journal article, 2019) -
Parallelism in thermal growth response in otoliths and scales of brown trout (Salmo trutta L.) from alpine lakes independent of genetic background
Thaulow, Jens; Haugen, Thrond Oddvar; Borgstrøm, Reidar (Journal article; Peer reviewed, 2017)Low density in natural populations of salmonids has predominantly been managed by stocking of non‐native conspecifics. Due partly to domestication, introduced non‐native fish may be maladapted under natural conditions. ... -
Smoltutvandring i Nidelva 2014-Utprøving av tiltak for nedvandrende smolt ved Rygene kraftverk
Haraldstad, Tormod; Guttrup, Jim; Haugen, Thrond Oddvar (NIVA-rapport;6760, Research report, 2014)Antall pre-smolt oppstrøms Rygene, 3546 (3083-4214), er lavere en hva en kunne forvente utfra antall oppvandrende gytefisk og egnet gyte- og oppvekstareal i elva. I tillegg estimeres et betydelig tap av smolt under ...