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Dupont, Nicolas; Durant, Joël; Langangen, Øystein Ole Gahr & Stige, Leif Christian
(2023).
Effects of abrupt ecological change on the Barents Sea Arctic food-web: predictions from a food-web state-space model.
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Dupont, Nicolas; Durant, Joël; Langangen, Øystein Ole Gahr & Stige, Leif Christian
(2023).
Survival of adult polar cod (Boreogadus saida) in the context of “borealization” of the Barents Sea
.
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Planque, Benjamin; Aarflot, Johanna Myrseth; Buttay, Lucie; Carroll, JoLynn; Fransner, Sara Filippa Krusmynta & Eide, Cecilie Hansen
[Show all 17 contributors for this article]
(2023).
A standard protocol for describing the evaluation of ecological models.
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Durant, Joël; Ono, Kotaro & Langangen, Øystein Ole Gahr
(2023).
Empirical evidence of non-linearity in the interaction between fish stocks in the Barents Sea.
Show summary
The strength of species interactions can have a significant impact on population dynamics. Empirical estimates of interaction strength are often based on the assumption that the interaction strength is constant. Several fish species interact in the Barents Sea and their population dynamics are typically modelled under the assumption of constant interaction strength. However, interactions between species are often non-linear in marine ecosystems and this could fundamentally change our understanding of food webs’ functioning. Here, we present two examples of such nonlinear interactions in the Barents Sea, between cod Gadus morhua and capelin Mallotus villosus, and between cod and haddock Melanogrammus aeglefinus. Analysis of long survey time series in the Arcto-boreal Barents Sea within a state-space modelling framework showed that the effect of capelin on cod is not linear but varies with capelin abundance. Similarly, interactions between cod and haddock have changed over the past two decades due to rising ocean temperatures, altering the equilibrium abundances and the dynamics of the system. Our analyses demonstrate that long-term climate change in the Arcto-boreal system leads to differences in equilibrium conditions for species communities and demonstrates the importance of investigating nonlinearities in species interactions, leading to a better understanding of species communities and species assemblages.
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Dupont, Nicolas; Durant, Joël; Langangen, Øystein Ole Gahr & Stige, Leif Christian
(2022).
Change in the Barents Sea Arctic food-web dynamic based on biotic and abiotic environmental factors.
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Dupont, Nicolas; Durant, Joël; Gjøsæter, Harald; Langangen, Øystein Ole Gahr & Stige, Leif Christian
(2021).
Using time series to predict the future: quantifying the effects of borealization on polar cod (Boreogadus saida).
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Dupont, Nicolas; Durant, Joel Marcel; Langangen, Øystein; Gjøsæter, Harald & Stige, Leif Christian
(2019).
Environmental effects on population annual mean length of polar cod (Boreogadus saida) in the Barents Sea
.
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Dupont, Nicolas; Durant, Joel Marcel; Langangen, Øystein; Gjøsæter, Harald & Stige, Leif Christian
(2019).
Environmental effects on population
annual mean length of polar cod (Boreogadus saida) in the Barents Sea
.
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Stige, Leif Christian; Durant, Joel Marcel & Langangen, Øystein
(2019).
Effects of climate change, fishing and oil on marine ecosystems.
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Stige, Leif Christian; Langangen, Øystein; Durant, Joel Marcel; Knutsen, Halvor; Olsen, Esben Moland & Ottersen, Geir
(2019).
Forskning på torsk.
Biolog.
ISSN 0801-0722.
37(2),
p. 46–49.
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Stige, Leif Christian; Rogers, Lauren; Neuheimer, Anna B.; Hunsicker, Mary E.; Yaragina, Natalia A. & Ottersen, Geir
[Show all 9 contributors for this article]
(2019).
Density- and size-dependent mortality in fish early life stages.
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Deris, Leana; Langangen, Øystein & Durant, Joel Marcel
(2018).
Effect of stock collapse on predator prey relationships.
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Färber, Leonie Anette; Sguotti, Camilla; Durant, Joel Marcel; Langangen, Øystein; Otto, Saskia A & Möllmann, Christian
(2018).
Detecting catastrophic transitions – the case of North Atlantic herring.
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Langangen, Øystein
(2018).
Long-term effects of local scale OIL pollution on fish Populations and COMmunities in the Lofoten-Barents Sea system (OILCOM).
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Stige, Leif Christian; Langangen, Øystein & Stenseth, Nils Christian
(2018).
Skreien ikke utenfor livsfare.
Dagens næringsliv.
ISSN 0803-9372.
p. 32–32.
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Stenseth, Nils Christian; Stige, Leif Christian & Langangen, Øystein
(2018).
Kunnskapsbasert forvaltning i et varmere klima.
Aftenposten (morgenutg. : trykt utg.).
ISSN 0804-3116.
p. 16–16.
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Deris, Leana; Langangen, Øystein & Durant, Joel Marcel
(2018).
Effect of cod (Gadus morhua) predation on juvenile herring (Clupea harengus) in the Barents Sea.
Show summary
The Barents Sea is a shelf sea sustaining a highly productive ecosystem including several commercially important fish stocks among which the Northeast Arctic (NEA) cod (Gadus morhua), Norwegian Spring Spawning (NSS) herring (Clupea harengus) and the Barents Sea (BS) capelin (Mallotus villosus) are key fish species in this ecosytem. NSS herring is currently one of the largest herring stocks in the world, and it is both an important prey (for e.g. cod and marine mammals) and predator species (for e.g. planktonic early life stages of fish and zooplankton).
It spawns in the Norwegian Sea in February-March and deposits eggs on the sea bottom. After hatching, larvae and 0-group appear in the upper water layer and drift by the coastal current to enter the Barents Sea where they spend their first 3 to 4 years of life before migrating to the north Atlantic as adult. It is during its juvenile life stage that the herring is susceptible to predation by the large stock of NEA cod.
Here, we develop a state-space model to estimate the effect of cod predation on young herring mortality. We used the obtained estimates to quantify at the population level the joint effect of fishing and cod predation on young herring. Our results indicate a significant effect of cod and illustrate how management of NSS herring benefits from jointly considering cod and fishing.
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Färber, Leonie Anette; Camilla, Sguotti; Durant, Joel Marcel; Langangen, Øystein; Otto, Saskia A & Möllmann, Christian
(2018).
Detecting catastrophic transitions – the case of North Atlantic herring.
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Dupont, Nicolas; Stige, Leif Christian & Langangen, Øystein
(2017).
Effects of heterogeneous spatial mortality on recruitment of Northeast Arctic cod (Gadus morhua) in the Barents Sea.
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Langangen, Øystein
(2017).
Multi-decadal variations in spawning ground use in Northeast Arctic haddock.
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Langangen, Øystein
(2017).
Ticket to spawn: combining economic and genetic data to evaluate the role of climate and harvesting on temporal shifts in spawning location.
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Stige, Leif Christian; Ottersen, Geir; Yaragina, Natalia A.; Stenseth, Nils Chr. & Langangen, Øystein
(2017).
Effect of a fish stock’s demographic structure on offspring exposure to possible oil spills.
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Färber, Leonie Anette; Durant, Joel Marcel; Vindenes, Yngvild & Langangen, Øystein
(2017).
Benefit of long distance migration for Barents Sea cod.
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Durant, Joel Marcel; Langangen, Øystein & Dupont, Nicolas
(2017).
Barents Sea cod larvae survival and match-mismatch
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Bellier, Edwige; Langangen, Øystein & Ohlberger, Jan Philipp
(2017).
Stage-dependent interactions of two harvested competitors.
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Diekert, Florian Klaus; Langangen, Øystein; Färber, Leonie Anette; Stige, Leif Christian & Durant, Joel Marcel
(2016).
Ticket to Spawn – Using economic data to shed light on biological hypothesis.
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Langangen, Øystein
(2016).
Multi-decadal changes in spawning ground use in Northeast Arctic haddock: Climate or harvest induced?
.
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Stige, Leif Christian; Kvile, Kristina Øie & Langangen, Øystein
(2016).
Zooplankton and fish: revealing key processes in predator−prey dynamics in the Barents Sea.
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Stige, Leif Christian; Kvile, Kristina Øie & Langangen, Øystein
(2016).
Zooplankton and fish: revealing key processes in predator‑prey dynamics in the Barents Sea.
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Kvile, Kristina Øie; Dalpadado, Padmini; Fiksen, Øyvind; Langangen, Øystein; Opdal, Anders Frugård & Prokopchuk, Irina P.
[Show all 8 contributors for this article]
(2016).
Climate responses of Calanus finmarchicus in a high latitude system.
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Kvile, Kristina Øie; Stige, Leif Christian; Prokopchuk, Irina P. & Langangen, Øystein
(2016).
A statistical regression approach to estimate zooplankton mortality from spatiotemporal survey data.
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Färber, Leonie Anette; Stige, Leif Christian; Durant, Joel Marcel; Diekert, Florian Klaus & Langangen, Øystein
(2016).
Ticket to Spawn – Using economic data to shed light on biological hypothesis.
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Vindenes, Yngvild; Langangen, Øystein; Winfield, Ian J. & Vøllestad, Leif Asbjørn
(2016).
The relative impacts of early life conditions and maternal size effects in determining average fitness and population growth of pike
.
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Vindenes, Yngvild; Langangen, Øystein; Winfield, Ian J. & Vøllestad, Leif Asbjørn
(2015).
Fitness consequences of early life conditions and maternal size effects in pike (Esox lucius)
.
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Vindenes, Yngvild; Langangen, Øystein; Winfield, Ian J. & Vøllestad, Leif Asbjørn
(2015).
Relative fitness importance of a size-mediated maternal effect – an integral projection model approach
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Vindenes, Yngvild; Langangen, Øystein; Winfield, Ian J. & Vøllestad, Leif Asbjørn
(2015).
Relative fitness consequences of early life conditions and maternal length in Windermere pike
.
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Carroll, JoLynn; Skeie, Geir Morten; Bogstad, Bjarte; Klok, Chris; Nepstad, Raymond & Juselius, Jonas
[Show all 32 contributors for this article]
(2014).
An ecosystem-based modeling system for predicting oil spill impacts in the marine environment.
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Langangen, Øystein
(2014).
Spatial variations in mortality in the early life-stages in a marine fish (Gadus Morhua).
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Kvile, Kristina Øie; Langangen, Øystein & Stige, Leif Christian
(2014).
Including drift in analyses of observation data reveals environmental effects on copepod biomass in the Barents Sea.
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Langangen, Øystein
(2013).
Spatial variations in mortality in pelagic early life stages of a marine fish (Gadus morhua).
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Nilsen, Ina; Eide, Cecilie Hansen; Olsen, Are; Langangen, Øystein Ole Gahr & Kaplan, Isaac
(2023).
Dealing with uncertainty in ecosystem models along three axes; resolution, forcing and projections.
Universitetet i Bergen.
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