Blar i Scientific publications på forfatter "Vøllestad, Leif Asbjørn"
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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 ... -
Contemporary ocean warming and freshwater conditions are related to later sea age at maturity in Atlantic salmon spawning in Norwegian rivers
Villar, Jaime Otero; Jensen, Arne Johan; Stenseth, Nils Christian; Storvik, Geir Olve; Vøllestad, Leif Asbjørn; L'Abée Lund, Henning (Journal article; Peer reviewed, 2012)Atlantic salmon populations are reported to be declining throughout its range, raising major management concerns. Variation in adult fish abundance may be due to variation in survival, growth, and timing of life history ... -
The evolving story of catadromy in the European eel (Anguilla anguilla)
Durif, Caroline; Arts, M.; Bertolini, F.; Cresci, Alessandro; Daverat, F.; Karlsbakk, Egil Erlingsson; Koprivnikar, J.; Moland, Even; Olsen, Esben Moland; Parzanini, C.; Power, M.; Rohtla, Mehis; Skiftesvik, Anne Berit; Thorstad, Eva Bonsak; Vøllestad, Leif Asbjørn; Browman, Howard (Peer reviewed; Journal article, 2023)Anguillid eels were once considered to be the classic example of catadromy. However, alternative life cycles have been reported, including skipping the freshwater phase and habitat shifting between fresh, brackish, and ... -
Habitat fragmentation has interactive effects on the population genetic diversity and individual behaviour of a freshwater salmonid fish
van Leeuwen, Casper; Dalen, Kristine; Museth, Jon; Junge, Claudia; Vøllestad, Leif Asbjørn (Journal article; Peer reviewed, 2017)Sufficient genetic diversity can aid populations to persist in dynamic and fragmented environments. Understanding which mechanisms regulate genetic diversity of riverine fish can therefore advance current conservation ... -
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 ... -
Mismatch between fishway operation and timing of fish movements: a risk for cascading effects in partial migration systems
van Leeuwen, Casper; Museth, Jon; Sandlund, Odd Terje; Qvenild, Tore; Vøllestad, Leif Asbjørn (Peer reviewed; Journal article, 2016)Habitat fragmentation is a growing problem worldwide. Particularly in river systems, numerous dams and weirs hamper the movement of a wide variety of species. With the aim to preserve connectivity for fish, many barriers ... -
Novel large-scale mapping highlights poor state of sea trout populations
Fiske, Peder; Forseth, Torbjørn; Thorstad, Eva Bonsak; Bakkestuen, Vegar; Einum, Sigurd; Falkegård, Morten; Garmo, Øyvind A.; Garseth, Åse Helen; Skoglund, Helge; Solberg, Monica Favnebøe; Utne, Kjell Rong; Vollset, Knut; Vøllestad, Leif Asbjørn; Wennevik, Vidar (Peer reviewed; Journal article, 2024)1. The state of sea trout in 1251 Norwegian watercourses was assessed based on a scoring system for human pressures, abundance data, and local knowledge. 2. Over 16,000 km of rivers and lakes were available to sea trout ... -
Predation of Atlantic salmon across ontogenetic stages and impacts on populations
Falkegård, Morten; Lennox, Robert; Thorstad, Eva Bonsak; Einum, Sigurd; Fiske, Peder; Garmo, Øyvind Aaberg; Garseth, Åse Helen; Skoglund, Helge; Solberg, Monica Favnebøe; Utne, Kjell Rong; Vollset, Knut; Vøllestad, Leif Asbjørn; Wennevik, Vidar; Forseth, Torbjørn (Peer reviewed; Journal article, 2023)Managers and stakeholders increasingly ask whether predation is a driving force behind the poor status of many species, and whether predator control is likely to be a successful management action to intervene. We review ... -
The potential influence of Atlantic salmon Salmo salar and brown trout Salmo trutta on density and breeding of the white-throated dipper Cinclus cinclus
Nilsson, Anna; L'Abee-Lund, Jan Henning; Vøllestad, Leif Asbjørn; Jerstad, Kurt; Larsen, Bjørn Mejdell; Røstad, Ole Wiggo; Saltveit, Svein Jakob; Skaugen, Thomas; Stenseth, Nils Christian; Walseng, Bjørn (Journal article; Peer reviewed, 2018)Interactions between birds and fish are often overlooked in aquatic ecosystems. We studied the influence of Atlantic salmon and brown trout on the breeding population size and reproductive output of the white-throated ... -
Timing and pattern of annual silver eel migration in two European watersheds are determined by similar cues
Sandlund, Odd Terje; Diserud, Ola Håvard; Poole, Russell; Bergesen, Knut Aanestad; Dillane, Mary; Rogan, Gerard; Durif, Caroline; Thorstad, Eva Bonsak; Vøllestad, Leif Asbjørn (Journal article; Peer reviewed, 2017)Many animals perform long-distance migrations in order to maximize lifetime reproductive success. The European eel migrates several thousand kilometers between their feeding habitats in continental waters (fresh-,brackish, ...