Collaborative Research: LTREB: RUI: Impacts of Insect Herbivory on the Pace and Pattern of Primary Successional Change at Mount St. Helens

Washington State University, Pullman WA

Investigators

Abstract

This project will test the hypothesis that insect herbivory is an unrecognized major factor influencing recovery of biological systems following the catastrophic 1980 eruption of Mount St. Helens (MSH). The work will quantify impacts of insect herbivores on two key "ecosystem engineering" plants: lupins, which facilitate soil development; and willows, the main source of three dimensional vegetation structure required by many animals. It will also evaluate the effects of herbivores on bird and mammals assemblages. The proposed work will extend the continuous study of insect herbivore impacts at MSH to 18 years, and of mammal community assembly and response to vegetation to 28 years, providing the most comprehensive data set on vertebrate response to catastrophic disturbance in the coniferous forest biome. How biological systems recover from catastrophic disturbances such as volcanic eruptions is fundamental to a basic understanding of how communities of plants and animals assemble and function, and provides the theoretical basis for environmental restoration. MSH has provided a unique opportunity to test ecological understanding of recovery from disturbance. Our work builds on this legacy by elucidating previously unrecognized mechanisms controlling recovery, and by providing long-term records accessible to future scientists. The project also enhances science education through student involvement and work with the National Volcanic Monument and its non-profit partner, the Mount St. Helens Institute.