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Probing the Limits of Egg Recognition Using Egg Rejection Experiments Along Phenotypic Gradients
Published on: August 22, 2018
Periodicity, persistence, and collapse in host-parasitoid systems with egg limitation
1Department of Mathematics, The College ofWilliam and Mary,Williamsburg, VA 23187-8795, USA. sjschr@wm.edu
Journal of Biological Dynamics
|August 11, 2012
Summary
Parasitoid biological control requires stabilizing factors like attack heterogeneity to manage insect pests. Aggregated parasitoid attacks promote coexistence, while random attacks can lead to host extinction.
Area of Science:
- Ecology
- Population Dynamics
- Biological Control
Background:
- Parasitoid populations are often limited by egg availability and host-searching time.
- Egg limitation can destabilize host-parasitoid interactions, necessitating stabilizing mechanisms for effective pest control.
- Heterogeneity in parasitoid attacks and host density-dependence are key factors influencing population stability.
Purpose of the Study:
- To analyze discrete time models of host-parasitoid dynamics incorporating egg limitation, search limitation, attack heterogeneity, and density-dependence.
- To determine the conditions under which parasitoids can successfully invade and coexist with host populations.
- To investigate the impact of the coefficient of variation (CV) of parasitoid attacks on population stability and outcomes.
Main Methods:
- Development and analysis of discrete time mathematical models.
- Analysis of host-parasitoid population dynamics under varying limitation and attack distribution scenarios.
- Numerical simulations to explore dynamics under different coefficients of variation (CV).
Main Results:
- Parasitoid invasion is contingent on intrinsic fitness exceeding host fitness.
- A critical threshold (CV*>1) for the coefficient of variation (CV) of attacks determines invasion success: CV>CV* leads to coexistence, while CV
- Weak search limitation allows coexistence even when CV
- Weak search limitation allows coexistence even when CV
Conclusions:
- Parasitoid attack aggregation (high CV) is crucial for stable coexistence with hosts.
- Heterogeneity in parasitoid attacks is a vital stabilizing mechanism in host-parasitoid systems.
- Understanding these dynamics is essential for optimizing classical biological control strategies.
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