Browsing NORCE vitenarkiv by Author "Lennox, Robert J."

Now showing items 1-14 of 14

    • A test of migratory coupling in the salmon-trout predator-prey complex of a subarctic fjord 

      Lennox, Robert J.; Espedal, Espen Olsen; Barlaup, Bjørn Torgeir; Mahlum, Shad Kenneth; Vollset, Knut (Peer reviewed; Journal article, 2019)
      Atlantic salmon (Salmo salar) smolts are vulnerable to predators during their seaward migration. To determine whether sea trout (Salmo trutta) exhibit a coupled migration to exploit the smolt run, we tracked Atlantic salmon ...

    • 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 ...

    • Development of a risk assessment for sea trout in coastal areas exploited for aquaculture 

      Finstad, Bengt; Sandvik, Anne Dagrun; Ugedal, Ola; Vollset, Knut; Karlsen, Ørjan; Davidsen, Jan Grimsrud; Sægrov, Harald; Lennox, Robert J. (Peer reviewed; Journal article, 2021)
      The regulation of aquaculture production in Norway considers the potential impact of salmon lice on wild fish. However, most attention has been focused on impacts on wild Atlantic salmon, despite the fact that anadromous ...

    • Drift diving: A quick and accurate method for assessment of anadromous salmonid spawning populations 

      Skoglund, Helge; Vollset, Knut; Lennox, Robert J.; Skaala, Øystein; Barlaup, Bjørn Torgeir (Peer reviewed; Journal article, 2021)
      The accuracy of drift diving surveys of Atlantic salmon, Salmo salar L. and sea trout, Salmo trutta L., was evaluated by comparing the abundance and size distribution with catches in a fish trap over 6 years in the River ...

    • How pathogens affect the marine habitat use and migration of sea trout (Salmo trutta) in two Norwegian fjord systems 

      Lennox, Robert J.; Eldøy, Sindre Håvarstein; Vollset, Knut; Miller, Kristi M.; Li, Shaorong; Kaukinen, Karia H.; Isaksen, Trond Einar; Davidsen, Jan Grimsrud (Peer reviewed; Journal article, 2020)
      Wild fish are confronting changing pathogen dynamics arising from anthropogenic disturbance and climate change. Pathogens can influence animal behaviour and life histories, yet there are little such data from fish in the ...

    • Laks i sjøørretbekker – villaks eller oppdrettslaks? 

      Pulg, Ulrich; Karlsson, Sten; Diserud, Ola H.; Postler, Christoph; Stranzl, Sebastian Franz; Espedal, Espen Olsen; Lennox, Robert J. (LFI - Laboratorium for ferskvannsøkologi og innlandsfiske;, Research report, 2020)
      Innkrysning av rømt oppdrettslaks vurderes som en av de største truslene mot villaks. Overvåking av innkrysning og innsig av oppdrettslaks samt uttak av oppdrettsfisk gjennomføres i en rekke lakseelver. I mindre kystvassdrag ...

    • Lakselusinfestasjon på vill laksefisk langs Norskekysten i 2020 - Sluttrapport til Mattilsynet 

      Nilsen, Rune; Serra Llinares, Rosa Maria; Sandvik, Anne Dagrun; Johnsen, Ingrid Askeland; Mohn, Agnes Marie; Karlsen, Ørjan; Lehmann, Gunnar Bekke; Birkeland, Ina Bakke; Stöger, Elisabeth; Lennox, Robert J.; Uglem, Ingebrigt; Berg, Marius (Rapport fra havforskningen, Research report, 2020)
      Overvåkingsprogrammet for lakselus på vill laksefisk (NALO) er i 2020 gjennomført på oppdrag fra Mattilsynet (MT) og Nærings- og Fiskeridepartementet (NFD). En hydrodynamisk spredningsmodell som beregner tetthet av infektive ...

    • Negative impacts of the sea lice prophylactic emamectin benzoate on the survival of hatchery released salmon smolts in rivers 

      Lennox, Robert J.; Salvanes, Anne Gro Vea; Barlaup, Bjørn Torgeir; Stöger, Elisabeth; Madhun, Abdullah; Helle, Turid Myklebust; Vollset, Knut (Peer reviewed; Journal article, 2020)
      Emamectin benzoate (EB) is a prophylactic pharmaceutical used to protect Atlantic salmon (Salmo salar) smolts migrating out of rivers and into the ocean against sea lice parasites. Randomized control trials comparing the ...

    • Predation research with electronic tagging 

      Lennox, Robert J.; Dahlmo, Lotte Svengård; Ford, Adam T.; Sortland, Lene K.; Vogel, Emma; Vollset, Knut Wiik (Peer reviewed; Journal article, 2022)
      Predation is a fundamental aspect of ecology that drives ecosystem structure and function. A better understanding of predation can be facilitated by using electronic tags that log or transmit positions of predator or prey ...

    • 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 (Journal article; Peer reviewed, 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 ...

    • Size dependent effects of passive integrated transponders (PIT-tags) on early life stages of salmon: a preliminary literature review 

      Vollset, Knut; Lennox, Robert J.; Mahlum, Shad Kenneth; Näslund, Joacim; Larsen, Martin H.; Thorstad, Eva B.; Frechette, Danielle; Finstad, Bengt; Davidsen, Jan Grimsrud (LFI – Laboratorium for ferskvannsøkologi og innlandsfiske, Research report, 2019)
      Passive Integrated Transponder (PIT) tags are commonly used to individually mark salmonids for assessing marine and freshwater survival, habitat use, and other aspects of life history essential for persistence of the ...

    • Systematic review and meta-analysis of PIT tagging effects on mortality and growth of juvenile salmonids 

      Vollset, Knut; Lennox, Robert J.; Thorstad, Eva Bonsak; Auer, Samuel; Bär, Kerstin; Larsen, Martin H.; Mahlum, Shad Kenneth; Näslund, Joacim; Stryhn, Henrik; Dohoo, Ian (Peer reviewed; Journal article, 2020)
      A systematic review and meta-analysis was conducted to evaluate the appropriate tag:fish size ratio when tagging juvenile salmonids (genera Oncorhynchus, Salmo, and Salvelinus). The review yielded 18 publications with 211 ...

    • 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 ...

    • Vurdering av overlevelsen til laksesmolt i Tysseelva ved bruk av akustisk telemetri Pilotstudie 2022 

      Gabrielsen, Sven-Erik; Berhe, Saron; Hanssen, Erlend Mjelde; Nilsen, Cecilie Iden; Normann, Eirik; Landro, Yngve; Lennox, Robert J.; Skår, Bjørnar; Vollset, Knut; Wiers, Tore (LFI - Laboratorium for ferskvannsøkologi og innlandsfiske, Research report, 2022)
      NORCE LFI fikk i mars 2022 en henvendelse fra Eviny v/Sissel H. Mykletun om å utføre undersøkelser for å prøve og avklare om laksesmolten overlever utvandringen ned Samnangervassdraget. Eviny har et elvekraftverk (Tyssefossen ...