Many bark beetles are closely associated with fungi. While the fungi gain transport to a new and otherwise inaccessible host tree, the benefit of the interaction to the beetle has been debated. One paradigm holds that the fungi help the beetle kill the tree; however, many of the fungi are nonpathogenic and many species of bark beetles are nonaggressive and attack only dead trees, yet may still be associated with fungi. The goal of this project is to determine if bark beetles benefit nutritionally from their fungal associates. Using laboratory and field studies, the effects of the two main filamentous fungal associates of mountain pine beetle on beetle fitness will be determined. Differences between the two fungal associates that may explain variation in benefits conferred to the beetle will also be investigated. Periodic outbreaks of mountain pine beetle cause significant economic losses in western North American forests. If fungal associates affect beetle fitness, this could affect the population dynamics of the insect. Thus, this research will not only contribute to the understanding of factors driving multispecies interactions and shaping ecological communities, but will also lead to a greater understanding of factors that may influence the population dynamics of a major forest pest. Results will be disseminated to middle and high school students as part of field trips and to the public during bark beetle workshops. This project will support the dissertation research of a doctoral student.
