Is Climate Warming Altering the Severity and Frequency of Forest Insect Outbreaks in the Northwest?

    Faculty Advisory

  • Patrick Tobin, University of Washington, pctobin@uw.edu
  • NW CASC Fellow

  • Alex Pane, University of Washington, apane@uw.edu
In Progress

The forests of the Northwest are host to many native and nonnative biotic disturbance agents (e.g., bark beetles and folivores). Higher temperatures, longer summers, and in turn, greater drought stress, are all likely to contribute to greater disturbance intensity, severity, and related tree mortality. Most research has focused on the singular effects of biotic disturbance agents on their respective host trees and short-term ecosystem responses following disturbance. However, disturbance rarely occurs in isolation; tree decline and mortality from interacting biotic disturbance agents is a complex, ongoing and poorly understood process. Biotic disturbance is an inherent ecological process in the Northwest; thus, understanding the patterns of biotic disturbance interactions is pivotal to the management and preservation of regional forests.

This project will look to fill current knowledge gaps by determining at risk native tree species and the potential impacts an invasive species may have on disturbance dynamics under a changing climate. We will also look to identify local-to-regional scale biotic and abiotic processes that enable repeated insect outbreaks to occur within forest ecosystems. The findings from this project could inform management strategies for both native and nonnative disturbance agents while providing insights into how these strategies may need to change to continue to succeed in a warming climate.