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Updated: Jul 12, 2026
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Linking Predation Risk, Herbivore Physiological Stress and Microbial Decomposition of Plant Litter
Published on: March 12, 2013
Environmental fluctuations can stabilize food web dynamics by increasing synchrony
David A Vasseur1, Jeremy W Fox
1Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada T2N 1N4. dvasseur@ucalgary.ca
Ecology Letters
|August 31, 2007
Summary
Environmental fluctuations can surprisingly stabilize complex food webs, even when they synchronize consumer dynamics. This challenges classical ecological theory by showing that synchrony, not asynchrony, can promote stability in natural ecosystems.
Area of Science:
- Ecology
- Ecological Dynamics
- Food Web Stability
Background:
- Species-rich natural food webs are theoretically prone to instability and extinction.
- Asynchronous consumer density fluctuations can stabilize food webs in constant environments.
- Environmental fluctuations often synchronize ecological dynamics in nature.
Purpose of the Study:
- To investigate the impact of environmentally induced fluctuations on food web stability.
- To determine if synchrony or asynchrony is more critical for stability under environmental fluctuations.
- To test if classical food web models predict stability under realistic environmental conditions.
Main Methods:
- Utilized a 'diamond-shape' food web model.
- Introduced environmentally induced fluctuations in consumer mortality rates.
- Analyzed the effects of weak-to-moderate fluctuation strengths on food web dynamics.
Main Results:
- Environmentally induced fluctuations stabilized food webs by disrupting asynchrony.
- Synchrony promoted stability through reduced top predator abundance during declines and resource competition during increases.
- Stabilizing effects were observed across various food web structures and fluctuation implementations.
Conclusions:
- Environmental fluctuations can stabilize species-rich food webs, contrary to classical theory.
- Synchronous dynamics, driven by environmental fluctuations, can enhance ecosystem stability.
- The findings suggest a realistic mechanism for food web stabilization in nature.
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