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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

Combined effects of fishing and oil spills on marine fish: Role of stock demographic structure for offspring overlap with oil.

https://arctichealth.org/en/permalink/ahliterature294288
Source
Mar Pollut Bull. 2018 Apr; 129(1):336-342
Publication Type
Journal Article
Date
Apr-2018
Author
Leif Chr Stige
Geir Ottersen
Natalia A Yaragina
Frode B Vikebø
Nils Chr Stenseth
Øystein Langangen
Author Affiliation
Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, P.O. Box 1066, Blindern, N-0316 Oslo, Norway. Electronic address: l.c.stige@ibv.uio.no.
Source
Mar Pollut Bull. 2018 Apr; 129(1):336-342
Date
Apr-2018
Language
English
Publication Type
Journal Article
Keywords
Animals
Arctic Regions
Computer simulation
Conservation of Natural Resources - methods
Environmental Monitoring - methods
Fisheries
Gadus morhua - growth & development
Petroleum Pollution - adverse effects
Population Dynamics
Reproduction
Abstract
It has been proposed that the multiple pressures of fishing and petroleum activities impact fish stocks in synergy, as fishing-induced demographic changes in a stock may lead to increased sensitivity to detrimental effects of acute oil spills. High fishing pressure may erode the demographic structure of fish stocks, lead to less diverse spawning strategies, and more concentrated distributions of offspring in space and time. Hence an oil spill may potentially hit a larger fraction of a year-class of offspring. Such a link between demographic structure and egg distribution was recently demonstrated for the Northeast Arctic stock of Atlantic cod for years 1959-1993. We here estimate that this variation translates into a two-fold variation in the maximal proportion of cod eggs potentially exposed to a large oil spill. With this information it is possible to quantitatively account for demographic structure in prospective studies of population effects of possible oil spills.
PubMed ID
29680556 View in PubMed
Less detail

Combined effects of fishing and oil spills on marine fish: Role of stock demographic structure for offspring overlap with oil.

https://arctichealth.org/en/permalink/ahliterature291417
Source
Mar Pollut Bull. 2018 Apr; 129(1):336-342
Publication Type
Journal Article
Date
Apr-2018
Author
Leif Chr Stige
Geir Ottersen
Natalia A Yaragina
Frode B Vikebø
Nils Chr Stenseth
Øystein Langangen
Author Affiliation
Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, P.O. Box 1066, Blindern, N-0316 Oslo, Norway. Electronic address: l.c.stige@ibv.uio.no.
Source
Mar Pollut Bull. 2018 Apr; 129(1):336-342
Date
Apr-2018
Language
English
Publication Type
Journal Article
Abstract
It has been proposed that the multiple pressures of fishing and petroleum activities impact fish stocks in synergy, as fishing-induced demographic changes in a stock may lead to increased sensitivity to detrimental effects of acute oil spills. High fishing pressure may erode the demographic structure of fish stocks, lead to less diverse spawning strategies, and more concentrated distributions of offspring in space and time. Hence an oil spill may potentially hit a larger fraction of a year-class of offspring. Such a link between demographic structure and egg distribution was recently demonstrated for the Northeast Arctic stock of Atlantic cod for years 1959-1993. We here estimate that this variation translates into a two-fold variation in the maximal proportion of cod eggs potentially exposed to a large oil spill. With this information it is possible to quantitatively account for demographic structure in prospective studies of population effects of possible oil spills.
PubMed ID
29680556 View in PubMed
Less detail

Competition among fishermen and fish causes the collapse of Barents Sea capelin.

https://arctichealth.org/en/permalink/ahliterature179006
Source
Proc Natl Acad Sci U S A. 2004 Aug 10;101(32):11679-84
Publication Type
Article
Date
Aug-10-2004
Author
Dag Ø Hjermann
Geir Ottersen
Nils Chr Stenseth
Author Affiliation
Centre for Ecological and Evolutionary Synthesis, Department of Biology, University of Oslo, Post Office Box 1050 Blindern, N-0316 Oslo, Norway.
Source
Proc Natl Acad Sci U S A. 2004 Aug 10;101(32):11679-84
Date
Aug-10-2004
Language
English
Publication Type
Article
Keywords
Animals
Ecosystem
Feeding Behavior
Fishes
Humans
Models, Theoretical
Predatory Behavior
Abstract
The vast majority of the world's fisheries are typically managed within a single-species perspective, ignoring the dynamic feedback mechanisms generated by the ecological web of which they are a part. Here we show that the dynamics of the Barents Sea capelin (Mallotus villosus), the world's largest stock of this species, is strongly influenced by both within-system ecological feedback mechanisms and the impact of harvesting. Both overexploitation and predation by herring (Clupea harengus) can cause the population to collapse, whereas predation by cod (Gadus morhua) is demonstrated a delay in the stock's recovery after a collapse. Such collapses, which have occurred twice in 20 years, affect the entire Barents Sea ecosystem, a region that for ages has provided food for all of Europe.
Notes
Cites: Science. 1984 Jun 1;224(4652):985-717731996
Cites: Trends Ecol Evol. 2004 Feb;19(2):101-816701236
PubMed ID
15286282 View in PubMed
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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
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Cites: Science. 1995 Aug 4;269(5224):676-9 PMID 17758812
PubMed ID
28115694 View in PubMed
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Productivity in the barents sea--response to recent climate variability.

https://arctichealth.org/en/permalink/ahliterature258856
Source
PLoS One. 2014;9(5):e95273
Publication Type
Article
Date
2014
Author
Padmini Dalpadado
Kevin R Arrigo
Solfrid S Hjøllo
Francisco Rey
Randi B Ingvaldsen
Erik Sperfeld
Gert L van Dijken
Leif C Stige
Are Olsen
Geir Ottersen
Source
PLoS One. 2014;9(5):e95273
Date
2014
Language
English
Publication Type
Article
Keywords
Animals
Biodiversity
Biomass
Chlorophyll - analogs & derivatives
Climate
Ecosystem
Oceanography
Oceans and Seas
Population Dynamics
Remote Sensing Technology
Reproducibility of Results
Satellite Imagery
Seasons
Temperature
Zooplankton
Abstract
The temporal and spatial dynamics of primary and secondary biomass/production in the Barents Sea since the late 1990s are examined using remote sensing data, observations and a coupled physical-biological model. Field observations of mesozooplankton biomass, and chlorophyll a data from transects (different seasons) and large-scale surveys (autumn) were used for validation of the remote sensing products and modeling results. The validation showed that satellite data are well suited to study temporal and spatial dynamics of chlorophyll a in the Barents Sea and that the model is an essential tool for secondary production estimates. Temperature, open water area, chlorophyll a, and zooplankton biomass show large interannual variations in the Barents Sea. The climatic variability is strongest in the northern and eastern parts. The moderate increase in net primary production evident in this study is likely an ecosystem response to changes in climate during the same period. Increased open water area and duration of open water season, which are related to elevated temperatures, appear to be the key drivers of the changes in annual net primary production that has occurred in the northern and eastern areas of this ecosystem. The temporal and spatial variability in zooplankton biomass appears to be controlled largely by predation pressure. In the southeastern Barents Sea, statistically significant linkages were observed between chlorophyll a and zooplankton biomass, as well as between net primary production and fish biomass, indicating bottom-up trophic interactions in this region.
Notes
Cites: Adv Mar Biol. 2003;46:225-34014601414
Cites: Science. 2005 May 27;308(5726):1280-415845876
Cites: Science. 2007 Feb 23;315(5815):1084-517322049
Cites: Ann N Y Acad Sci. 2008;1134:267-31918566098
Cites: PLoS One. 2012;7(1):e2894522276100
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Cites: Biol Lett. 2012 Dec 23;8(6):1012-522977068
PubMed ID
24788513 View in PubMed
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8 records – page 1 of 1.