A three-species model explaining cyclic dominance of Pacific salmon

JOURNAL OF THEORETICAL BIOLOGY

卷:276

Article

Guill, Christian¹  Drossel, Barbara¹  Just, Wolfram²  Carmack, Eddy³ 

[1] Tech Univ Darmstadt, Inst Festkorperphys, D-64289 Darmstadt, Germany

[2] Queen Mary Univ London, Sch Math Sci, London E1 4NS, England

[3] Fisheries & Oceans Canada Inst Ocean Sci, Sidney, BC V8L 4B2, Canada

关键词: Cyclic dominance;    Population oscillations;    Single-generation cycles;    Neimark Sacker bifurcation;    Strong resonance;   

DOI  :  10.1016/j.jtbi.2011.01.036

来源: Elsevier

【 摘 要 】

The four-year oscillations of the number of spawning sockeye salmon (Oncorhynchus nerka) that return to their native stream within the Fraser River basin in Canada are a striking example of population oscillations. The period of the oscillation corresponds to the dominant generation time of these fish. Various-not fully convincing-explanations for these oscillations have been proposed, including stochastic influences, depensatory fishing, or genetic effects. Here, we show that the oscillations can be explained as an attractor of the population dynamics, resulting from a strong resonance near a Neimark Sacker bifurcation. This explains not only the long-term persistence of these oscillations, but also reproduces correctly the empirical sequence of salmon abundance within one period of the oscillations. Furthermore, it explains the observation that these oscillations occur only in sockeye stocks originating from large oligotrophic lakes, and that they are usually not observed in salmon species that have a longer generation time. (C) 2011 Elsevier Ltd. All rights reserved.

【 授权许可】

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