Blar i NTNU Open på forfatter "Diserud, Ola Håvard"

Viser treff 1-16 av 16

    • A survey of freshwater fishes and their macroparasites in the Guanacaste Conservation Area (ACG), Costa Rica 

      Sandlund, Odd Terje; Daverdin, Rita; Choudhury, Anindo; Brooks, Daniel R.; Diserud, Ola Håvard (NINA rapport;635, Research report, 2010)
      Freshwater fish were collected mainly by electrofishing in 27 localities in rivers and streams within the Area de Conservacion Guanacaste in northwestern Costa Rica, in June 1998 (rainy season), February 1999 and March ...

    • Characteristics of temporal changes in communities where dynamics differ between species 

      Solbu, Erik Blystad; Engen, Steinar; Diserud, Ola Håvard (Journal article; Peer reviewed, 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 ...

    • Choice of DNA extraction method affects DNA metabarcoding of unsorted invertebrate bulk samples 

      Majaneva, Markus; Diserud, Ola Håvard; Hajibabaei, Mehrdad; Eagle, Shannon; Ekrem, Torbjørn (Journal article; Peer reviewed, 2018)
      Characterisation of freshwater benthic biodiversity using DNA metabarcoding may allow more cost-effective environmental assessments than the current morphological-based assessment methods. DNA metabarcoding methods where ...

    • Early-season brown trout (Salmo trutta) migrants grow and survive better at sea 

      Jensen, Arne Johan; Diserud, Ola Håvard; Finstad, Bengt; Fiske, Peder; Thorstad, Eva Bonsak (Peer reviewed; Journal article, 2022)
      The timing of seaward migration is a key life-history trait for many anadromous fish species, with growth and survival at sea depending on a match/mismatch scenario between the timing of the sea entry and optimal conditions. ...

    • Environmental DNA filtration techniques affect recovered biodiversity 

      Majaneva, Markus; Diserud, Ola Håvard; Eagle, Shannon; Boström, Erik; Hajibabaei, Mehrdad; Ekrem, Torbjørn (Journal article; Peer reviewed, 2018)
      Freshwater metazoan biodiversity assessment using environmental DNA (eDNA) captured on filters offers new opportunities for water quality management. Filtering of water in the field is a logistical advantage compared to ...

    • 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 ...

    • 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 ...

    • 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 ...

    • Modeling salmon lice effects on sea trout population dynamics using an individual-based approach 

      Hedger, Richard David; Diserud, Ola Håvard; Finstad, Bengt; Jensen, Arne Johan; Hendrichsen, Ditte Katrine; Ugedal, Ola; Næsje, Tor (Peer reviewed; Journal article, 2021)
      Salmon lice Lepeophtheirus salmonis infestation of sea trout Salmo trutta results in both additional marine mortality and behavioral changes which may contribute to sea trout population decline. For effective management ...

    • Modellering av gjellealuminium. Aluminiumspåslag på gjellene til laksesmolt og betydningen dette kan ha for utvandringen 

      Diserud, Ola Håvard; Kroglund, Frode; Teien, Hans-Christian; Tjomsland, Torulv; Økland, Finn (NINA rapport;773, Research report, 2012)
      Etter kalking av Storelva i Holt har utvandringen av smolt vært betydelig, mens fangstene av laks i elva fortsatte å være lave (Kroglund mfl. 2011c). I 2005 ble det observert smolt i dårlig form og uten fluktatferd i ...

    • 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 Gravbrøt; Sauterleute, Julian Friedrich; Tøfte, Lena S; Alfredsen, Knut; Forseth, Torbjørn (Journal article; Peer reviewed, 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 ...

    • 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 (Journal article; Peer reviewed, 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 ...

    • Repowering Smøla wind-power plant - An assessment of avian conflicts 

      Dahl, Espen Lie; May, Roelof Frans; Nygård, Torgeir; Åström, Jens; Diserud, Ola Håvard (NINA Rapport;1135, Research report, 2015)
      Gjennom pågående og tidligere forskning på effekter av vindkraft på fugl i Smøla vindpark, er havørn identifisert som den mest sårbare arten. Smøla vindpark påvirker havørn både gjennom økt dødelighet som følge av kollisjoner ...

    • The risk of individual fish being captured multiple times in a catch and release fishery 

      Thorstad, Eva Bonsak; Diserud, Ola Håvard; Solem, Øyvind; Havn, Torgeir Børresen; Bjørum, Lars Rasmus Oftedal; Kristensen, Torstein; Urke, Henning Andre; Johansen, Martin Rognli; Lennox, Robert J.; Fiske, Peder; Uglem, Ingebrigt (Peer reviewed; Journal article, 2019)
      The proportion of angled Atlantic salmon Salmo salar L. being caught and released has increased. If individuals are repeatedly captured, this may have fish welfare consequences. Of 995 Atlantic salmon tagged during catch ...

    • 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 ...

    • Why do we find dead bumblebees under linden trees? 

      Vinnes, Malene Kyrkjebø; Haugen, Inger Marie Aalberg; Diserud, Ola Håvard; Ødegaard, Frode; Gjershaug, Jan Ove (Peer reviewed; Journal article, 2022)
      1. Linden trees (Tilia spp.) have for a long time been associated with bumblebee (Bombus spp.) mortality in Europe and North America. Several explanations have been suggested for this phenomenon. This study aimed to explore ...