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Spatial heterogeneity, population "regulation" and local extinction in simulated host-parasitoid interactions
1Department of Entomology, University of Maryland, 20742, College Park, MD, USA.
Oecologia
|March 18, 2017
Summary
Spatial heterogeneity in local populations may allow natural enemies to regulate prey, but simulations show frequent local extinctions. The "spreading of risk" concept better explains these dynamics than traditional regulation models.
Area of Science:
- Ecology
- Population Dynamics
- Mathematical Biology
Background:
- Spatial heterogeneity influences ecological interactions.
- Conventional analyses may miss fine-scale regulatory effects.
- Previous models suggested spatial effects on population regulation.
Purpose of the Study:
- Investigate how spatial heterogeneity affects population regulation by natural enemies.
- Evaluate the applicability of the "spreading of risk" concept versus traditional regulation models.
- Address debates on spatial heterogeneity in insect population modeling.
Main Methods:
- Utilized simulation models to explore population dynamics.
- Analyzed interactions between hosts/prey and parasitoids/natural enemies.
- Compared model outputs to conventional k-factor analyses and life table data.
Main Results:
- Spatial heterogeneity can lead to population regulation undetectable by standard methods.
- Simulated populations frequently experienced local extinction events.
- The "spreading of risk" concept provided a better fit than stable equilibrium models.
Conclusions:
- Spatial heterogeneity plays a significant role in population dynamics.
- Local extinctions are a common outcome in spatially heterogeneous environments.
- "Spreading of risk" offers a valuable framework for understanding these complex ecological interactions.
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