Prevention and Early Detection of Invasive Earthworms

Earthworms are common throughout much of Minnesota, but few realize that they are not native to the state and were in fact introduced from Europe and Asia. Earthworms are invasive in Minnesota and have been shown to have large and potentially irreversible impacts on hardwood forest biodiversity and regeneration. As dispersal by human actions is the primary means of introduction and spread of invasive earthworms, there exists great potential to arrest the current spread of earthworms already present and prevent the introduction of additional species. This appropriation is being used by the Natural Resources Research Institute at the University of Minnesota - Duluth to:

• Identify the areas of the state at greatest risk from invasive earthworms,
• Assess the different ways worms are transported to currently worm-free areas,
• Develop strategies to slow or prevent their further spread, and
• Conduct outreach to inform and engage various stakeholders in actions aimed at preventing further spread of earthworms.

Overall Project Outcome and Results
We used a multi-pronged approach to quantify the relative importance of different vectors of spread for invasive earthworms, make management and regulatory recommendations, and create mechanisms for public engagement and dissemination of our project results through the Great Lakes Worm Watch website and to diverse stakeholders. Internet sales of earthworms and earthworm related products pose large risks for the introduction of new earthworm species and continued spread of those already in the state. Of 38 earthworm products sampled, 87% were either contaminated with other earthworm species or provided inaccurate identification. Assessment of soil transported via ATV's and logging equipment demonstrated that this is also a high risk vector for spread of earthworms across the landscape, suggesting that equipment hygiene, land management activities, and policies should address this risk. Preliminary recommendations for organizations with regulatory oversight for invasive earthworms (i.e. MN-DNR, MDA and MPCA) include the implementation of required trainings on invasive earthworms for commercial operations involved in any enterprise using or selling earthworm or earthworm products (i.e. fishing bait, composting, etc.). Recommended trainings would be similar to those already required of minnow bait operations. Finally, substantial efforts were completed to train, inform, and actively engage diverse stakeholders in efforts to document invasive earthworm and their relative impacts across the state/region and to identify earthworm-free and minimally impacted areas worthy of protection. As a result of this project we added 716 survey points and 9,697 specimens to our database and worked directly with 40 groups and over 1300 individuals (e.g. citizens, college students-teachers, K-12 students-teachers, natural resource managers, and researchers) in 10 different states (Minnesota, Wisconsin, Ohio, New York, Massachusetts, Virginia, Pennsylvania, Alaska, Kentucky, Michigan). Five peer-reviewed publications, a second edition of the book "Earthworms of the Great Lakes", and two online maps were produced and disseminate our results.

Project Results Use and Dissemination
The project has allowed us to greatly enhance and expand the quality and quantity of resources provided through the Great Lakes Worm Watch website. In addition to the many people we interact with directly there are thousands that access our website resources annually. In 2012, Great Lakes Worm Watch established and now maintains a Facebook page. We use the platform, linked to our website, to communicate research, outreach and educational opportunities.

Additionally, this project has resulted in five peer-reviewed publications; information has been presented at 20 professional seminars/conferences and approximately 40 trainings to natural resource professionals, students, and the public; media coverage in over 40 different stories; and participated in numerous other public outreach activities such as exhibits at conferences and fairs.