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arXiv · 1503.01843

Host-feeding enhances stability of discrete-time host-parasitoid population dynamic models

Brooks Emerick·Abhyudai Singh
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Abstract

Discrete-time models are the traditional approach for capturing population dynamics of a host-parasitoid system. Recent work has introduced a semi-discrete framework for obtaining model update functions that connect host-parasitoid population levels from year-to-year. In particular, this framework uses differential equations to describe the hosts-parasitoid interaction during the time of year where they come in contact, allowing specific behaviors to be mechanistically incorporated into the model. We use the semi-discrete approach to study the effects of host-feeding, which occurs when a parasitoid consumes a potential host larva without ovipositing. Our results show that host-feeding by itself cannot stabilize the system, and both the host and parasitoid populations exhibit diverging oscillations similar to the Nicholson-Bailey model. However, when combined with other stabilizing mechanisms such as density-dependent host mortality or density-dependent parasitoid attack rate, host-feeding expands the region of parameter space that allows for a stable host-parasitoid equilibrium. Finally, our results show that host-feeding causes inefficiency in the parasitoid population, which yields a higher population of hosts per generation. This suggests that host-feeding may have limited long-term impact in terms of suppressing host levels for biological control applications.

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Brooks Emerick, Abhyudai Singh. 2015-03-06. Host-feeding enhances stability of discrete-time host-parasitoid population dynamic models. https://arxiv.org/abs/1503.01843

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