Competition-induced starvation drives large-scale population cycles in Antarctic krill

Antarctic krill (Euphausia superba)—one of the most abundant animal species on Earth—exhibits a five to six year population cycle, with oscillations in biomass exceeding one order of magnitude. Previous studies have postulated that the krill cycle is induced by periodic climatological factors, but t...

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Bibliographic Details
Published in:Nature Ecology & Evolution
Main Authors: Ryabov, Alexey B., de Roos, André M., Meyer, Bettina, Kawaguchi, So, Blasius, Bernd
Format: Article in Journal/Newspaper
Language:unknown
Published: Springer Nature 2017
Subjects:
Online Access:https://epic.awi.de/id/eprint/45025/
https://epic.awi.de/id/eprint/45025/1/Ryabovetal2017.pdf
https://epic.awi.de/id/eprint/45025/2/Ryabovetal2017suppl.pdf
https://hdl.handle.net/10013/epic.51269
https://hdl.handle.net/10013/epic.51269.d001
https://hdl.handle.net/10013/epic.51269.d002
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Summary:Antarctic krill (Euphausia superba)—one of the most abundant animal species on Earth—exhibits a five to six year population cycle, with oscillations in biomass exceeding one order of magnitude. Previous studies have postulated that the krill cycle is induced by periodic climatological factors, but these postulated drivers neither show consistent agreement, nor are they supported by quantitative models. Here, using data analysis complemented with modelling of krill ontogeny and population dynamics, we identify intraspecific competition for food as the main driver of the krill cycle, while external climatological factors possibly modulate its phase and synchronization over large scales. Our model indicates that the cycle amplitude increases with reduction of krill loss rates. Thus, a decline of apex predators is likely to increase the oscillation amplitude, potentially destabilizing the marine food web, with drastic consequences for the entire Antarctic ecosystem.