Browsing Brage IMR by Author "Pedersen, Torstein"
Now showing items 1-20 of 23
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A standard protocol for describing the evaluation of ecological models
Planque, Benjamin; Aarflot, Johanna Myrseth; Buttay, Lucie; Carroll, JoLynn; Fransner, Sara Filippa Krusmynta; Hansen, Cecilie; Husson, Berengere; Langangen, Øystein Ole Gahr; Lindstrøm, Ulf Ove; Pedersen, Torstein; Primicerio, Raul; Sivel, Elliot Manuarii; Skogen, Morten D.; Strombom, Evelyn; Stige, Leif Christian; Varpe, Øystein; Yoccoz, Nigel (Peer reviewed; Journal article, 2022)Numerical models o ecological systems are increasingly used to address complex environmental and resource management questions. One challenge or scientists, managers, and stakeholders is to appraise how well suited these ... -
Can multitrophic interactions and ocean warming influence large-scale kelp recovery?
Christie, Hartvig C; Gundersen, Hege; Rinde, Eli; Filbee-Dexter, Karen; Norderhaug, Kjell Magnus; Pedersen, Torstein; Bekkby, Trine; Gitmark, Janne Kim; Fagerli, Camilla With (Journal article; Peer reviewed, 2019)Ongoing changes along the northeastern Atlantic coastline provide an opportunity to explore the influence of climate change and multitrophic interactions on the recovery of kelp. Here, vast areas of sea urchin‐dominated ... -
Community structure of deep fjord and shelf benthic fauna receiving different detrital kelp inputs in northern Norway
Ramirez-Llodra, Eva; Pedersen, Torstein; Filbee-Dexter, Karen; Hauquier, Freija; Guilini, Katja; Mikkelsen, Nina; Borgersen, Gunhild; van Gyseghem, Margo; Vanreusel, Ann; Vilas, Daniel (Peer reviewed; Journal article, 2020)Kelp forests produce large amounts of macroalgal detritus, ranging from whole plants to small particles (1 mm). The role of this kelp detritus in fueling deep-sea communities adjacent to healthy kelp forests was investigated ... -
Do capelin larvae deposit daily increments in their otoliths?
Ivarjord, Trond; Pedersen, Torstein; Moksness, Erlend (ICES CM documents, Working paper, 2004)Analysis of increment formation in larval fish otoliths has provided valuable information about growth, transport and mortality processes of larvae in wild stocks, but the technique has not been widely used on capelin ... -
Essay om fiskerier i Porsangerfjorden før og nå - et resultat av møter mellom fjordbrukere og forskere
Strand, Hans Kristian; Daleng, Jan; Eliassen, Tore; Follesø, Thor; Gjøsæter, Harald; Hansen, Hans Oliver; Hansen, Thomas; Johansen, Hartvig; Josefsen, Hedly; Larsen, Dagny; Martinsen, Terje; Nedreaas, Kjell Harald; Pedersen, Torstein; Skern-Mauritzen, Mette; Strand, Mette; Søvik, Guldborg; Zimmermann, Fabian (Rapport fra havforskningen;2020 - 41, Research report, 2020)Porsangerfjorden gikk fra å være en fiskerik fjord i første halvdelen av 1900-tallet, til en mye mer fiskefattig fjord i den andre halvdelen. Den fiskefattige tilstanden har vedvart fram til i dag. Den invaderende kongekrabben ... -
Extreme male-skewed sex ratios on spaning grounds for Atlantic cod Gadus morhua with typical coastal cod signatures of the Pan I (pantophysin) locus
Fevolden, Svein-Erik; Westgaard, Jon-Ivar; Pedersen, Torstein (Journal article; Peer reviewed, 2015-06-11)Large offshore and small inshore populations of Atlantic cod Gadus morhua L. display differences in migratory patterns and settling regimes, but little is known about possible differences in spawning behaviour. Cod presumably ... -
Future trajectories of change for an Arctic deep-sea ecosystem connected to coastal kelp forests
Vilas, Daniel; Coll, Marta; Pedersen, Torstein; Corrales, Xavier; Filbee-Dexter, Karen; Wernberg, Thomas (Peer reviewed; Journal article, 2021)Environmental stressors related to climate change and other anthropogenic activities are impacting Arctic marine ecosystems at exceptional rates. Within this context, predicting future scenarios of deep-sea ecosystems and ... -
Growth rates and age distributions of capelin (Mallotus villosus) larvae in the Barents Sea investigated by otolith increment analysis
Jakobsen, Ronny A.; Pedersen, Torstein; Moksness, Erlend (ICES CM documents, Working paper, 2004)In order to investigate age distributions and growth rates, otoliths from capelin larvae collected from the Barents Sea during the summers 2001-2003 were analysed using otolith microstructure analysis. Stations were ... -
Kelp-carbon uptake by Arctic deep-sea food webs plays a noticeable role in maintaining ecosystem structural and functional traits
Vilas, Daniel; Coll, Marta; Pedersen, Torstein; Corrales, Xavier; Filbee-Dexter, Karen; Pedersen, Morten Foldager; Norderhaug, Kjell Magnus; Fredriksen, Stein; Wernberg, Thomas; Ramirez-Llodra, Eva (Peer reviewed; Journal article, 2020)The flow of non-living carbon (detritus) is considered an important process because it connects ecosystems and fuels benthic communities. In Norwegian kelp forests, 90% of the kelp production is exported to adjacent ... -
Life history genomic regions explain differences in Atlantic salmon marine diet specialization
Aykanat, Tutku; Rasmussen, Martin; Ozerov, Mikhail; Niemelä, Eero; Paulin, Lars; Vähä, Juha-Pekka; Hindar, Kjetil; Wennevik, Vidar; Pedersen, Torstein; Svenning, Martin; Primmer, Craig R. (Peer reviewed; Journal article, 2020) -
Mass production of juvenile Atlantic cod (Gadus morhua L.) in a pond: results and new approaches in 1985
Folkvord, Arild; Kvenseth, Per Gunnar; Pedersen, Torstein; Øiestad, Victor (ICES CM Documents;1985/F:63, Working paper, 1985)Large scale production of juvenile Atlantic cod has been carried out since 1980. A break-through was obtained in 1983 with high survival rates of cod larvae to metamorphosis. This year we have tried to solve two remaining ... -
Mass-production of cod fry (Gadus morhua L.) in a large basin in western Norway - a new approach
Øiestad, Victor; Kvenseth, Per Gunnar; Pedersen, Torstein (ICES CM Documents;1984/F:16, Working paper, 1984)In February 1984, the fresh water in a small lake was replaced by seawater pumped from 40 m depth. Four-day old cod larvae were transferred on 11 and 26 April into this seawater basin, which was 5 m above sea level with ... -
Modelling the spatial shifts of functional groups in the Barents Sea using a climate-driven spatial food web model
Nascimento, Marcela Conceicao; Husson, Berengere; Guillet, Lilia; Pedersen, Torstein (Peer reviewed; Journal article, 2023)We built a dynamic, spatial food web model for the Barents Sea, developed with Ecospace by including species’ habitat requirements and ecological interactions. The model was used to test the spatial shifts of different ... -
Overexploitation, Recovery, and Warming of the Barents Sea Ecosystem During 1950–2013
Pedersen, Torstein; Mikkelsen, Nina; Lindstrøm, Ulf; Renaud, Paul Eric; Nascimento, Marcela C.; Blanchet, Marie-Anne; Ellingsen, Ingrid H.; Jørgensen, Lis L.; Blanchet, Hugues (Peer reviewed; Journal article, 2021)The Barents Sea (BS) is a high-latitude shelf ecosystem with important fisheries, high and historically variable harvesting pressure, and ongoing high variability in climatic conditions. To quantify carbon flow pathways ... -
Possibilities and limitations of extensive aquaculture of marine fish: evaluation of current results with Atlantic cod and further prospects
Kristiansen, Tore S.; Pedersen, Torstein; Svåsand, Terje (ICES CM documents, Working paper, 1998) -
Predation mortality from ambush and cruising predators on newly-settled 0-group gadoids
Pedersen, Torstein; Strand, Hans Kristian; Christie, Hartvig C; Moy, Frithjof (Peer reviewed; Journal article, 2020)We investigated predation from an ambush predator (shorthorn sculpin) and two cruising predators (Atlantic cod and saithe) on bottom-settled 0-group cod and saithe juveniles in a fjord in northern Norway. Stomach contents ... -
Predation of oyster larvae by Aurelia aurita in a Norwegian oyster pond
Aase, Hans; Misund, Ole Arve; Pedersen, Torstein (ICES CM Documents;1986/F:21, Working paper, 1986)In the norwegian oyster spatting ponds several factors may influence the spat production. During a basic, general study in a pond in 1983-84, Aurelia aurita was demonstrated to be a heavy predator on pelagic oyster ... -
Predation on early life stages is decisive for year-class strength in the Barents Sea capelin (Mallotus villosus) stock
Gjøsæter, Harald; Hallfredsson, Elvar H.; Mikkelsen, Nina; Bogstad, Bjarte; Pedersen, Torstein (Journal article; Peer reviewed, 2015-10-11)Year-class strength of Barents Sea capelin has been monitored closely since the early 1970s and during this ∼45 years period three short periods of almost total recruitment failure leading to three stock collapses have ... -
Settling-depth vs. genotype and size vs. genotype correlations at the Pan I locus in 0-group Atlantic cod Gadus morhua
Fevolden, Svein-Erik; Westgaard, Jon-Ivar; Pedersen, Torstein; Præbel, Kim (Journal article; Peer reviewed, 2012-11-14)We sampled 0-group juvenile Atlantic cod Gadus morhua L. within fjords and offshore in northern Norway from 1994 to 2008 using different gears for the 3 sampling depths: shore seine (0−3 m), pelagic trawl (various depths), ... -
Size of spawning Arcto-Norwegian cod (Gadus morhua L.) and the effects on their eggs and early larvae
Solemdal, Per; Bergh, Øivind; Dahle, Geir; Falk-Petersen, Inger-Britt; Fyhn, Hans Jørgen; Grahl-Nielsen, Otto; Haaland, J.M.; Kjesbu, Olav Sigurd; Løken, Sissel; Opstad, Ingegjerd; Pedersen, Torstein; Skiftesvik, Anne Berit; Thorsen, Anders (ICES CM Documents;1993/G:41, Working paper, 1993)Using a new method for determining the stage of spawning in batch spawners, a positive correlation between the length of Arcto-Norwegian cod females, having spawned 25-75% of their eggs, and the egg diameter was established. ...