Global climate change effects on forest insect outbreak dynamics

University Of Virginia Main Campus, Charlottesville VA

Investigators

Abstract

Climate change may alter the outbreak dynamics of forest-defoliating insects, with potential consequences for both the economy and the environment. Although numerous studies predict that climate change will increase the frequency and severity of outbreaks, few studies have examined whether recent climate trends have impacted outbreak dynamics. Furthermore, the results of those few studies have not been consistent. Outbreak histories of 10 forest-defoliating insect species and long-term climate datasets will be examined to determine whether the regularity, frequency, and magnitude of outbreaks have shifted over time relative to long-term norms, and to evaluate whether shifts in dynamics may be influenced by climate changes. Potential causes of shifts in outbreak dynamics will be investigated by fitting quantitative population growth models to historical outbreak data, and then integrating the results from the models with existing knowledge of biological interactions (e.g., disease, parasitism) that influence the population sizes of each defoliator species. Finally, the impacts of climate change on the outbreak dynamics of forest-defoliating insects as a whole will be assessed by synthesizing the findings for individual species. This project will contribute to a better understanding of whether changes in climate have led to shifts in the population behavior of forest-defoliating insect species. The project will also shed light on the effects of changes in climate on the biological interactions ultimately responsible for population cycles. Broader impacts of this project include potential recommendations for pest control programs. For example, control plans could be modified by selecting biological control agents (e.g., diseases) that are likely to become more effective in the future due to climatic trends. In addition, research techniques and findings will be disseminated to science-curriculum supervisors for preK-12 schools.