System dynamics of the Barents Sea capelin
The capelin ( Mallotus villosus) in the Barents Sea plays a key role in the Arctic food web. The large fluctuations in the biomass of the Barents Sea capelin have been poorly understood and collapses in the biomass have occurred. A system analysis of the capelin stock has identified a state differen...
Published in: | ICES Journal of Marine Science |
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Main Authors: | , |
Format: | Text |
Language: | English |
Published: |
Oxford University Press
2002
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Subjects: | |
Online Access: | http://icesjms.oxfordjournals.org/cgi/content/short/59/6/1155 https://doi.org/10.1006/jmsc.2002.1285 |
Summary: | The capelin ( Mallotus villosus) in the Barents Sea plays a key role in the Arctic food web. The large fluctuations in the biomass of the Barents Sea capelin have been poorly understood and collapses in the biomass have occurred. A system analysis of the capelin stock has identified a state differential equation model and a frequency transfer function model of the stock properties. The results of this research show that the capelin stock dynamics is adapted to the 18.6 year and the 18.6/3=6.2 year lunar nodal tide that influences the temperature in the Barents Sea. An analysis of the capelin time series has identified a 6.2 yr cycle of recruitment, maturity and fish stock growth. An estimated frequency response of a stock-number, life-cycle model has identified a stochastic resonance of about half of the 6.2 yr cycle. The stochastic resonance shows that fluctuation of the stock number is a natural adaptation to the environment and a strategy for optimal growth and survival in the long run. In this stochastic resonance timing between the stock number fluctuation and the 6.2 yr cycle is most important. |
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