Blar i Scientific publications på forfatter "Diserud, Ola Håvard"
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Age of European silver eels during a period of declining abundance in Norway
Durif, Caroline; Diserud, Ola Håvard; Sandlund, Odd Terje; Thorstad, Eva Bonsak; Poole, Russell; Bergesen, Knut Aanestad; Escobar-Lux, Rosa H.; Shema, Steven; Vøllestad, Leif Asbjørn (Journal article, 2020)The European eel (Anguilla anguilla) is critically endangered throughout its range. Knowledge about age distribution of future spawners (silver eels) is essential to monitor the status and contribute to the recovery of ... -
Bias in estimates of electrofishing capture probability of juvenile Atlantic salmon
Hedger, Richard David; Diserud, Ola Håvard; Sandlund, Odd Terje; Saksgård, Laila M.; Ugedal, Ola; Bremset, Gunnbjørn (Journal article; Peer reviewed, 2018)We evaluated the effect of the total number of passes used, and the application of block nets, on multi-pass electrofishing removal sampling for estimating juvenile Atlantic salmon (Salmo salar L.) abundance and body size ... -
Bioenergetic consequences of warming rivers to adult Atlantic salmon Salmo salar during their spawning migration
Lennox, Robert J.; Eliason, Erika J.; Havn, Torgeir Børresen; Johansen, Martin Rognli; Thorstad, Eva Bonsak; Cooke, Steven J.; Diserud, Ola Håvard; Whoriskey, Frederick G.; Farrell, Anthony P.; Uglem, Ingebrigt (Journal article; Peer reviewed, 2018)1. Climate change poses a challenge to wild fishes, yet little is known about the behavioural use and metabolic consequences of thermally heterogeneous water encountered by wild salmon during their energetically demanding ... -
Biotic and abiotic determinants of the ascent behaviour of adult Atlantic salmon transiting passable waterfalls
Lennox, Robert J.; Thorstad, Eva Bonsak; Diserud, Ola Håvard; Økland, Finn; Cooke, Steven J.; Aasestad, Ingar; Forseth, Torbjørn (Journal article; Peer reviewed, 2018)The spawning migration of Atlantic salmon has been characterized by tracking salmon carrying electronic tags as they ascend rivers, but still little is known about how natural obstacles such as waterfalls influence migratory ... -
Characteristics of temporal changes in communities where dynamics differ between species
Solbu, Erik Blystad; Engen, Steinar; Diserud, Ola Håvard (Peer reviewed; Journal article, 2016)Communities with different phenotypic variation among species can have identical species abundance distributions, although their temporal dynamics may be very different. By using stochastic species abundance models, both ... -
Escaped farmed Atlantic salmon in Norwegian rivers during 1989–2013
Diserud, Ola Håvard; Fiske, Peder; Sægrov, Harald; Urdal, K.; Aronsen, Tonje; Lo, Håvard; Barlaup, Bjørn Torgeir; Niemela, Eero; Orell, P.; Erkinaro, J.; Lund, Roar A.; Økland, Finn; Østborg, Gunnel Marie; Hansen, Lars Petter; Hindar, Kjetil (Journal article; Peer reviewed, 2019)We report on the data from an extensive monitoring programme for the occurrence of escaped farmed Atlantic salmon (Salmo salar) in Norwegian rivers for 25 years. This monitoring started as a 3-year research programme in ... -
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 ... -
Genetic evidence of farmed straying and introgression in Swedish wild salmon populations
Palm, Stefan; Karlsson, Sten; Diserud, Ola Håvard (Peer reviewed; Journal article, 2021)Escaped farmed Atlantic salmon represent a well-documented and ongoing threat to wild conspecific populations. In Norway, the world-leading producer of farmed salmon, annual monitoring of straying and genetic introgression ... -
Heterogeneity among species and community dynamics – Norwegian bird communities as a case study
Solbu, Erik Blystad; Diserud, Ola Håvard; Kålås, John Atle; Engen, Steinar (Journal article; Peer reviewed, 2018)We have in this study analysed bird communities across Norway with a heterogeneous species abundance model, where dynamical parameters can vary among species. Similarity in community composition over time, used as a measure ... -
Infection by the cestodes Triaenophorus crassus and Diphyllobothrium spp. in a polymorphic whitefish population
Sandlund, Odd Terje; Næsje, Tor; Diserud, Ola Håvard (Peer reviewed; Journal article, 2021)The whitefish (Coregonus lavaretus s.l.) stock in Lake Femunden, Norway, includes three morphs: deepwater spawning (D-), river spawning (R-) and shallow water spawning (S-) whitefish. Infections by Diphyllobothrium spp. ... -
Influence of gear switching on recapture of Atlantic salmon (Salmo salar) in catch-and- release fisheries
Lennox, Robert J.; Diserud, Ola Håvard; Cooke, Steven J.; Thorstad, Eva Bonsak; Whoriskey, Frederick G.; Solem, Øyvind; Havn, Torgeir Børresen; Uglem, Ingebrigt (Journal article; Peer reviewed, 2016)Anglers that release Atlantic salmon (Salmo salar) in recreational fisheries do so with the intention that the fish will survive and contribute to succeeding generations. In some instances, salmon that are released may be ... -
Integrative taxonomy of the Changeable Hawk-Eagle Nisaetus cirrhatus complex (Accipitriformes: Accipitridae) in India
Gjershaug, Jan Ove; Diserud, Ola Håvard; Kleven, Oddmund; Rasmussen, P.C.; Espmark, Yngve (Peer reviewed; Journal article, 2020)The Changeable Hawk-Eagle Nisaetus cirrhatus complex is represented by two taxa in mainland India: N. c. cirrhatus in the northern plains and peninsula and N. c. limnaeetus in the Himalayan foothills. Traditionally these ... -
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 ... -
Long-term variation in numbers and biomass of silver eels being produced in two European river systems
Poole, W. Russell; Diserud, Ola Håvard; Thorstad, Eva Bonsak; Durif, Caroline; Dolan, Conor; Sandlund, Odd Terje; Bergesen, Knut Aanestad; Rogan, Gerard; Kelly, Sean D.; Vøllestad, Leif Asbjørn (Journal article; Peer reviewed, 2018)The European eel (Anguilla anguilla) population has been in decline at least since the 1960s and reliable regional information, particularly on the spawner production and escapement (i.e. the silver eel life stage), is a ... -
Modelling climate change effects on Atlantic salmon: Implications for mitigation in regulated rivers
Sundt-Hansen, Line Elisabeth Breivik; Hedger, Richard David; Ugedal, Ola; Diserud, Ola Håvard; Finstad, Anders G.; Sauterleute, Julian Friedrich; Tøfte, Lena S.; Alfredsen, Knut; Forseth, Torbjørn (Peer reviewed; Journal article, 2018)Climate change is expected to alter future temperature and discharge regimes of rivers. These regimes have a strong influence on the life history of most aquatic river species, and are key variables controlling the growth ... -
Modelling the effect of hydropeaking‐induced stranding mortality on Atlantic salmon population abundance
Hedger, Richard David; Sauterleute, Julian Friedrich; Sundt-Hansen, Line Elisabeth Breivik; Forseth, Torbjørn; Ugedal, Ola; Diserud, Ola Håvard; Bakken, Tor Haakon (Journal article; Peer reviewed, 2018)Studies of hydropeaking‐induced stranding mortality on fish populations have been confined to analysis of empirical data and/or short‐term hydraulic‐habitat modelling of individual events and are thus limited as to how ... -
Movements of dead fish in rivers
Havn, Torgeir Børresen; Økland, Finn; Teichert, Maxim A.K.; Heermann, L.; Borcherding, J; Sæther, Stein Are; Tambets, M.; Diserud, Ola Håvard; Thorstad, Eva Bonsak (Journal article; Peer reviewed, 2017)Background: The aim of telemetry studies is often to determine the fate and mortality rates of ish. A moving ish is usually regarded as alive and a long-term stationary ish as dead—and the site where it became stationary ... -
Natural and anthropogenic drivers of escaped farmed salmon occurrence and introgression into wild Norwegian Atlantic salmon populations
Diserud, Ola Håvard; Fiske, Peder; Karlsson, Sten; Glover, Kevin Alan; Næsje, Tor; Aronsen, Tonje; Bakke, Gunnar O; Barlaup, Bjørn Torgeir; Erkinaro, J.; Florø-Larsen, Bjørn; Foldvik, Anders; Heino, Mikko Petteri; Kanstad-Hanssen, Øyvind; Lo, Håvard; Lund, Roar Asbjørn; Muladal, R.; Niemela, E.; Økland, Finn; Østborg, Gunnel Marie; Otterå, Håkon Magne; Skaala, Øystein; Skoglund, Helge; Solberg, Ingrid; Solberg, Monica Favnebøe; Sollien, Vegard Pedersen; Sægrov, Harald; Urdal, Kurt; Wennevik, Vidar; Hindar, Kjetil (Peer reviewed; Journal article, 2022)Marine aquaculture of Atlantic salmon (Salmo salar) is a relatively new industry where breeding programs have led to rapid genetic change in the captive populations that were built up alongside conspecific wild individuals. ... -
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 ...