Invasive Earthworms in the Crown of the Continent System and Implications for Land Management

Author

Meghan Elizabeth Scott, University of Montana, Missoula

Year of Award

2022

Document Type

Professional Paper

Degree Type

Master of Science (MS)

Degree Name

Environmental Studies

Department or School/College

Environmental Studies Program

Committee Chair

Dan Spencer

Commitee Members

Len Broberg, Vicki Watson

Keywords

earthworms, Crown of the Continent, soil ecology, Montana, Canada

Subject Categories

Other Ecology and Evolutionary Biology | Other Forestry and Forest Sciences | Terrestrial and Aquatic Ecology

Abstract

The United States contains invasive earthworms originating from Europe and Asia; the majority are European lumbricids. Direct introduction occurs primarily through human activity and, once established, earthworm populations are difficult to address. When exotic earthworms engage in bioturbation, they negatively alter subterranean food webs and nutrient cycling by disrupting soil layering systems. The most prominent form of physical alteration is the change and removal of the topmost organic layer. This disruption is associated with altered nitrogen and carbon cycling, as well as altered forest floor plant communities.

The Crown of the Continent ecosystem is located in southwestern Alberta, southeastern British Columbia and northwestern Montana. This unique transboundary system is home to distinct biodiversity and is less altered by humans than many other ecosystems. The presence of exotic earthworms introduces new challenges for land managers and local soil systems. Current US policy offers an ineffective “innocent until proven guilty” attitude towards introduced species. Preventing spread and mitigating the effects of exotic earthworms is needed to preserve soil quality. Non-native earthworms and earthworm products could be banned and/or restricted by land managers to prevent further spread. Supplemental action, such as invasive species education programs, can enhance preventative practices.

Recommended Citation

Scott, Meghan Elizabeth, "Invasive Earthworms in the Crown of the Continent System and Implications for Land Management" (2022). Graduate Student Theses, Dissertations, & Professional Papers. 11974.
https://scholarworks.umt.edu/etd/11974