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Climate based multi-year predictions of the Barents Sea cod stock.

https://arctichealth.org/en/permalink/ahliterature295553
Source
PLoS One. 2018; 13(10):e0206319
Publication Type
Journal Article
Date
2018
Author
Marius Årthun
Bjarte Bogstad
Ute Daewel
Noel S Keenlyside
Anne Britt Sandø
Corinna Schrum
Geir Ottersen
Author Affiliation
Geophysical Institute, University of Bergen, 5007 Bergen, Norway.
Source
PLoS One. 2018; 13(10):e0206319
Date
2018
Language
English
Publication Type
Journal Article
Abstract
Predicting fish stock variations on interannual to decadal time scales is one of the major issues in fisheries science and management. Although the field of marine ecological predictions is still in its infancy, it is understood that a major source of multi-year predictability resides in the ocean. Here we show the first highly skilful long-term predictions of the commercially valuable Barents Sea cod stock. The 7-year predictions are based on the propagation of ocean temperature anomalies from the subpolar North Atlantic toward the Barents Sea, and the strong co-variability between these temperature anomalies and the cod stock. Retrospective predictions for the period 1957-2017 capture well multi-year to decadal variations in cod stock biomass, with cross-validated explained variance of over 60%. For lead times longer than one year the statistical long-term predictions show more skill than operational short-term predictions used in fisheries management and lagged persistence forecasts. Our results thus demonstrate the potential for ecosystem-based fisheries management, which could enable strategic planning on longer time scales. Future predictions show a gradual decline in the cod stock towards 2024.
PubMed ID
30356300 View in PubMed
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Climate based multi-year predictions of the Barents Sea cod stock.

https://arctichealth.org/en/permalink/ahliterature299316
Source
PLoS One. 2018; 13(10):e0206319
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
2018
Author
Marius Årthun
Bjarte Bogstad
Ute Daewel
Noel S Keenlyside
Anne Britt Sandø
Corinna Schrum
Geir Ottersen
Author Affiliation
Geophysical Institute, University of Bergen, 5007 Bergen, Norway.
Source
PLoS One. 2018; 13(10):e0206319
Date
2018
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Animals
Climate
Fisheries - trends
Forecasting
Gadus morhua - physiology
Linear Models
Oceans and Seas
Population Density
Seasons
Abstract
Predicting fish stock variations on interannual to decadal time scales is one of the major issues in fisheries science and management. Although the field of marine ecological predictions is still in its infancy, it is understood that a major source of multi-year predictability resides in the ocean. Here we show the first highly skilful long-term predictions of the commercially valuable Barents Sea cod stock. The 7-year predictions are based on the propagation of ocean temperature anomalies from the subpolar North Atlantic toward the Barents Sea, and the strong co-variability between these temperature anomalies and the cod stock. Retrospective predictions for the period 1957-2017 capture well multi-year to decadal variations in cod stock biomass, with cross-validated explained variance of over 60%. For lead times longer than one year the statistical long-term predictions show more skill than operational short-term predictions used in fisheries management and lagged persistence forecasts. Our results thus demonstrate the potential for ecosystem-based fisheries management, which could enable strategic planning on longer time scales. Future predictions show a gradual decline in the cod stock towards 2024.
PubMed ID
30356300 View in PubMed
Less detail

Effect of a fish stock's demographic structure on offspring survival and sensitivity to climate.

https://arctichealth.org/en/permalink/ahliterature279559
Source
Proc Natl Acad Sci U S A. 2017 Jan 23;
Publication Type
Article
Date
Jan-23-2017
Author
Leif Christian Stige
Natalia A Yaragina
Øystein Langangen
Bjarte Bogstad
Nils Chr Stenseth
Geir Ottersen
Source
Proc Natl Acad Sci U S A. 2017 Jan 23;
Date
Jan-23-2017
Language
English
Publication Type
Article
Abstract
Commercial fishing generally removes large and old individuals from fish stocks, reducing mean age and age diversity among spawners. It is feared that these demographic changes lead to lower and more variable recruitment to the stocks. A key proposed pathway is that juvenation and reduced size distribution causes reduced ranges in spawning period, spawning location, and egg buoyancy; this is proposed to lead to reduced spatial distribution of fish eggs and larvae, more homogeneous ambient environmental conditions within each year-class, and reduced buffering against negative environmental influences. However, few, if any, studies have confirmed a causal link from spawning stock demographic structure through egg and larval distribution to year class strength at recruitment. We here show that high mean age and size in the spawning stock of Barents Sea cod (Gadus morhua) is positively associated with high abundance and wide spatiotemporal distribution of cod eggs. We find, however, no support for the hypothesis that a wide egg distribution leads to higher recruitment or a weaker recruitment-temperature correlation. These results are based on statistical analyses of a spatially resolved data set on cod eggs covering a period (1959-1993) with large changes in biomass and demographic structure of spawners. The analyses also account for significant effects of spawning stock biomass and a liver condition index on egg abundance and distribution. Our results suggest that the buffering effect of a geographically wide distribution of eggs and larvae on fish recruitment may be insignificant compared with other impacts.
PubMed ID
28115694 View in PubMed
Less detail

Effect of a fish stock's demographic structure on offspring survival and sensitivity to climate.

https://arctichealth.org/en/permalink/ahliterature291333
Source
Proc Natl Acad Sci U S A. 2017 02 07; 114(6):1347-1352
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
02-07-2017
Author
Leif Christian Stige
Natalia A Yaragina
Øystein Langangen
Bjarte Bogstad
Nils Chr Stenseth
Geir Ottersen
Author Affiliation
Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, N-0316 Oslo, Norway; n.c.stenseth@ibv.uio.no l.c.stige@ibv.uio.no.
Source
Proc Natl Acad Sci U S A. 2017 02 07; 114(6):1347-1352
Date
02-07-2017
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Animals
Climate
Conservation of Natural Resources - methods
Female
Fisheries
Gadus morhua - physiology
Geography
Larva - physiology
Male
Norway
Oceans and Seas
Ovum - physiology
Population Dynamics
Population Growth
Russia
Abstract
Commercial fishing generally removes large and old individuals from fish stocks, reducing mean age and age diversity among spawners. It is feared that these demographic changes lead to lower and more variable recruitment to the stocks. A key proposed pathway is that juvenation and reduced size distribution causes reduced ranges in spawning period, spawning location, and egg buoyancy; this is proposed to lead to reduced spatial distribution of fish eggs and larvae, more homogeneous ambient environmental conditions within each year-class, and reduced buffering against negative environmental influences. However, few, if any, studies have confirmed a causal link from spawning stock demographic structure through egg and larval distribution to year class strength at recruitment. We here show that high mean age and size in the spawning stock of Barents Sea cod (Gadus morhua) is positively associated with high abundance and wide spatiotemporal distribution of cod eggs. We find, however, no support for the hypothesis that a wide egg distribution leads to higher recruitment or a weaker recruitment-temperature correlation. These results are based on statistical analyses of a spatially resolved data set on cod eggs covering a period (1959-1993) with large changes in biomass and demographic structure of spawners. The analyses also account for significant effects of spawning stock biomass and a liver condition index on egg abundance and distribution. Our results suggest that the buffering effect of a geographically wide distribution of eggs and larvae on fish recruitment may be insignificant compared with other impacts.
Notes
Cites: Proc Biol Sci. 2012 Jan 22;279(1727):275-83 PMID 21676978
Cites: Proc Natl Acad Sci U S A. 2012 Jun 5;109(23):8995-9 PMID 22615381
Cites: Glob Chang Biol. 2015 Mar 10;:null PMID 25758656
Cites: Proc Natl Acad Sci U S A. 2014 Mar 4;111(9):3478-83 PMID 24550465
Cites: J Anim Ecol. 2016 May;85(3):692-704 PMID 26781671
Cites: Glob Chang Biol. 2015 Apr;21(4):1521-30 PMID 25336028
Cites: Biol Lett. 2010 Apr 23;6(2):261-4 PMID 19923140
Cites: Science. 1995 Aug 4;269(5224):676-9 PMID 17758812
PubMed ID
28115694 View in PubMed
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Predator-prey interactions cause apparent competition between marine zooplankton groups.

https://arctichealth.org/en/permalink/ahliterature303052
Source
Ecology. 2018 03; 99(3):632-641
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
03-2018
Author
Leif Christian Stige
Kristina Ø Kvile
Bjarte Bogstad
Øystein Langangen
Author Affiliation
Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, P.O. Box 1066, N-0316, Oslo, Norway.
Source
Ecology. 2018 03; 99(3):632-641
Date
03-2018
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Animals
Biomass
Climate change
Ecosystem
Fishes
Population Dynamics
Zooplankton
Abstract
Predator-mediated apparent competition is an indirect negative interaction between two prey species mediated by a shared predator. Quantifying such indirect ecosystem effects is methodologically challenging but important for understanding ecosystem functioning. Still, there are few examples of apparent competition from pelagic marine environments. Using state-space statistical modeling, we here provide evidence for apparent competition between two dominant zooplankton groups in a large marine ecosystem, i.e., krill and copepods in the Barents Sea. This effect is mediated by a positive association between krill biomass and survival of the main planktivorous fish in the Barents Sea, capelin Mallotus villosus, and a negative association between capelin and copepod biomasses. The biomass of Atlantic krill species is expected to increase in the Barents Sea due to ongoing climate change, thereby potentially negatively affecting copepods through apparent competition. By demonstrating and quantifying apparent competition in a large marine ecosystem, our study paves the way for more realistic projections of indirect ecosystem effects of climate change and harvesting.
PubMed ID
29281755 View in PubMed
Less detail

Predator-prey interactions cause apparent competition between marine zooplankton groups.

https://arctichealth.org/en/permalink/ahliterature287916
Source
Ecology. 2017 Dec 27;
Publication Type
Article
Date
Dec-27-2017
Author
Leif Christian Stige
Kristina Ø Kvile
Bjarte Bogstad
Øystein Langangen
Source
Ecology. 2017 Dec 27;
Date
Dec-27-2017
Language
English
Publication Type
Article
Abstract
Predator-mediated apparent competition is an indirect negative interaction between two prey species mediated by a shared predator. Quantifying such indirect ecosystem effects is methodologically challenging but important for understanding ecosystem functioning. Still, there are few examples of apparent competition from pelagic marine environments. Using state-space statistical modeling, we here provide evidence for apparent competition between two dominant zooplankton groups in a large marine ecosystem, i.e., krill and copepods in the Barents Sea. This effect is mediated by a positive association between krill biomass and survival of the main planktivorous fish in the Barents Sea, capelin Mallotus villosus, and a negative association between capelin and copepod biomasses. The biomass of Atlantic krill species is expected to increase in the Barents Sea due to ongoing climate change, thereby potentially negatively affecting copepods through apparent competition. By demonstrating and quantifying apparent competition in a large marine ecosystem, our study paves the way for more realistic projections of indirect ecosystem effects of climate change and harvesting.
PubMed ID
29281755 View in PubMed
Less detail

6 records – page 1 of 1.