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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
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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

Disentangling the mechanisms behind climate effects on zooplankton.

https://arctichealth.org/en/permalink/ahliterature269701
Source
Proc Natl Acad Sci U S A. 2016 Feb 1;
Publication Type
Article
Date
Feb-1-2016
Author
Kristina Ø Kvile
Øystein Langangen
Irina Prokopchuk
Nils C Stenseth
Leif C Stige
Source
Proc Natl Acad Sci U S A. 2016 Feb 1;
Date
Feb-1-2016
Language
English
Publication Type
Article
Abstract
Understanding how climate influences ecosystems is complicated by the many correlated and interrelated impacting factors. Here we quantify climate effects on Calanus finmarchicus in the northeastern Norwegian Sea and southwestern Barents Sea. By combining oceanographic drift models and statistical analyses of field data from 1959 to 1993 and investigating effects across trophic levels, we are able to elucidate pathways by which climate influences zooplankton. The results show that both chlorophyll biomass in spring and C. finmarchicus biomass in summer relate positively to a combination of shallow mixed layer depth and increased wind in spring, suggesting that C. finmarchicus biomass in summer is influenced by bottom-up effects of food availability. Furthermore, spatially resolved C. finmarchicus biomass in summer is linked to favorable transport from warmer, core areas to the south. However, increased mean temperature in spring does not lead to increased C. finmarchicus biomass in summer. Rather, spring biomass is generally higher, but population growth from spring to summer is lower, after a warm compared with a cold spring. Our study illustrates how improved understanding of climate effects can be obtained when different datasets and different methods are combined in a unified approach.
PubMed ID
26831099 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
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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Population resilience to catastrophic mortality events during early life stages.

https://arctichealth.org/en/permalink/ahliterature267712
Source
Ecol Appl. 2015 Jul;25(5):1348-56
Publication Type
Article
Date
Jul-2015
Author
Jan Ohlberger
Øystein Langangen
Source
Ecol Appl. 2015 Jul;25(5):1348-56
Date
Jul-2015
Language
English
Publication Type
Article
Keywords
Aging
Animals
Biomass
Ecosystem
Environmental monitoring
Gadiformes - physiology
Larva
Models, Biological
Ovum
Population Density
Population Dynamics
Time Factors
Abstract
Catastrophic mortality events that drastically reduce the abundance of a population or a particular life stage can have long-term ecological and economic effects, and are of great concern in species conservation and management. Severe die-offs may be caused by natural catastrophes such as disease outbreaks and extreme climates, or human-caused disturbances such as toxic spills. Forecasting potential impacts of such disturbances is difficult and highly uncertain due to unknown future conditions, including population status and environmental conditions at the time of impact. Here, we present a framework for quantifying the range of potential, population-level effects of catastrophic events based on a hindcasting approach. A dynamic population model with Bayesian parameter estimation is used to simulate the impact of severe (50-99%) mortality events during the early life stages of Northeast Arctic cod (Gadus morhua), an abundant marine fish population of high economic value. We quantify the impact of such die-offs in terms of subsequent changes in population biomass and harvest through direct comparison of simulated and historical trends, and estimate the duration of the impact as a measure of population resilience. Our results demonstrate strong resilience to catastrophic events that affect early life stages owing to density dependence in survival and a broad population age structure. Yet, while population recovery is. relatively fast, losses in harvest and economic value can be substantial. Future research efforts should focus on long-term and indirect effects via food web interactions in order to better understand the ecological and economic ramifications of catastrophic mortality events.
PubMed ID
26485960 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

Ticket to spawn: Combining economic and genetic data to evaluate the effect of climate and demographic structure on spawning distribution in Atlantic cod.

https://arctichealth.org/en/permalink/ahliterature295360
Source
Glob Chang Biol. 2018 Oct 09; :
Publication Type
Journal Article
Date
Oct-09-2018
Author
Øystein Langangen
Leonie Färber
Leif C Stige
Florian K Diekert
Julia M I Barth
Michael Matschiner
Paul R Berg
Bastiaan Star
Nils Chr Stenseth
Sissel Jentoft
Joël M Durant
Author Affiliation
Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, Oslo, Norway.
Source
Glob Chang Biol. 2018 Oct 09; :
Date
Oct-09-2018
Language
English
Publication Type
Journal Article
Abstract
Climate warming and harvesting affect the dynamics of species across the globe through a multitude of mechanisms, including distribution changes. In fish, migrations to and distribution on spawning grounds are likely influenced by both climate warming and harvesting. The Northeast Arctic (NEA) cod (Gadus morhua) performs seasonal migrations from its feeding grounds in the Barents Sea to spawning grounds along the Norwegian coast. The distribution of cod between the spawning grounds has historically changed at decadal scales, mainly due to variable use of the northern and southern margins of the spawning area. Based on historical landing records, two major hypotheses have been put forward to explain these changes: climate and harvesting. Climate could affect the distribution through, for example, spatial habitat shifts. Harvesting could affect the distribution through impacting the demographic structure. If demographic structure is important, theory predicts increasing spawner size with migration distance. Here, we evaluate these hypotheses with modern data from a period (2000-2016) of increasing temperature and recovering stock structure. We first analyze economic data from the Norwegian fisheries to investigate geographical differences in size of spawning fish among spawning grounds, as well as interannual differences in mean latitude of spawning in relation to changes in temperature and demographic parameters. Second, we analyze genetically determined fish sampled at the spawning grounds to unambiguously separate between migratory NEA cod and potentially smaller sized coastal cod of local origin. Our results indicate smaller spawners farther away from the feeding grounds, hence not supporting the hypothesis that harvesting is a main driver for the contemporary spawning ground distribution. We find a positive correlation between annual mean spawning latitude and temperature. In conclusion, based on contemporary data, there is more support for climate compared to harvesting in shaping spawning ground distribution in this major fish stock in the North Atlantic Ocean.
PubMed ID
30300937 View in PubMed
Less detail

Ticket to spawn: Combining economic and genetic data to evaluate the effect of climate and demographic structure on spawning distribution in Atlantic cod.

https://arctichealth.org/en/permalink/ahliterature298445
Source
Glob Chang Biol. 2019 01; 25(1):134-143
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
01-2019
Author
Øystein Langangen
Leonie Färber
Leif C Stige
Florian K Diekert
Julia M I Barth
Michael Matschiner
Paul R Berg
Bastiaan Star
Nils Chr Stenseth
Sissel Jentoft
Joël M Durant
Author Affiliation
Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, Oslo, Norway.
Source
Glob Chang Biol. 2019 01; 25(1):134-143
Date
01-2019
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Animal Distribution
Animals
Atlantic Ocean
Climate change
Fisheries - economics
Gadus morhua - genetics - physiology
Norway
Reproduction
Abstract
Climate warming and harvesting affect the dynamics of species across the globe through a multitude of mechanisms, including distribution changes. In fish, migrations to and distribution on spawning grounds are likely influenced by both climate warming and harvesting. The Northeast Arctic (NEA) cod (Gadus morhua) performs seasonal migrations from its feeding grounds in the Barents Sea to spawning grounds along the Norwegian coast. The distribution of cod between the spawning grounds has historically changed at decadal scales, mainly due to variable use of the northern and southern margins of the spawning area. Based on historical landing records, two major hypotheses have been put forward to explain these changes: climate and harvesting. Climate could affect the distribution through, for example, spatial habitat shifts. Harvesting could affect the distribution through impacting the demographic structure. If demographic structure is important, theory predicts increasing spawner size with migration distance. Here, we evaluate these hypotheses with modern data from a period (2000-2016) of increasing temperature and recovering stock structure. We first analyze economic data from the Norwegian fisheries to investigate geographical differences in size of spawning fish among spawning grounds, as well as interannual differences in mean latitude of spawning in relation to changes in temperature and demographic parameters. Second, we analyze genetically determined fish sampled at the spawning grounds to unambiguously separate between migratory NEA cod and potentially smaller sized coastal cod of local origin. Our results indicate smaller spawners farther away from the feeding grounds, hence not supporting the hypothesis that harvesting is a main driver for the contemporary spawning ground distribution. We find a positive correlation between annual mean spawning latitude and temperature. In conclusion, based on contemporary data, there is more support for climate compared to harvesting in shaping spawning ground distribution in this major fish stock in the North Atlantic Ocean.
PubMed ID
30300937 View in PubMed
Less detail

10 records – page 1 of 1.