Document Type
Article
Journal/Book Title/Conference
SIAM Journal on Applied Mathematics
Volume
77
Issue
1
Publisher
Society for Industrial and Applied Mathematics Publications
Publication Date
2-22-2017
First Page
294
Last Page
314
Abstract
Outbreaks of phytophagous forest insects are largely driven by host demographics and spatial effects of dispersal. We develop a structured integrodifference equation (IDE) outbreak model that tracks the demographics of sedentary hosts under insect infestation pressure. The model is appropriate for a spectrum of pests attacking the later age classes of long-lived hosts, including mountain pine beetle (MPB), spruce budworm, and spruce beetle, which, among them are responsible for more forest damage than fire. The model generates a train of periodic waves of infestation. We approximate the IDE with a partial differential equation and search for traveling wave solutions. The resulting ordinary differential equation predicts the shape of an outbreak wave profile and peak infestation as functions of wavefront speed, which can be calculated analytically. This culminates in the derivation of an explicit approximation of invasion wave amplitude based on net reproductive rate of the infesting insect and its host searching efficiency. Results are compared with observations taken during a recent MPB outbreak in the northern US Rocky Mountains.
Recommended Citation
Duncan, J.P., Powell, J.A. Analytic approximation of invasion wave amplitude predicts severity of insect outbreaks (2017) SIAM Journal on Applied Mathematics, 77 (1), pp. 294-314.
Comments
http://epubs.siam.org/doi/10.1137/15M1042085