The history of zebra mussel control in Minnesota began in the early 2000s. The initial pilot projects used physical and chemical methods in an attempt to eradicate zebra mussels and prevent further spread within the state. As earlier detection monitoring became more prevalent, zebra mussel introductions were found sooner and partial lakes treatments were attempted. While these efforts have been successful in controlling zebra mussels in confined areas, lakewide control or eradication of new populations remains a challenge.
- 1989 — Zebra mussels discovered in Lake Superior
- 2000 — First inland lake discovery, first control effort in Minnesota (Lake Zumbro drawdown)
- 2011 — First partial lake pesticide treatment in response to a new infestation
- 2015 — DNR & MAISRC develop ZM monitoring protocols for rapid response projects
- 2018 — First research project examining treatment of veligers in an enclosed bay
- Treatment of zebra mussels in Minnesota lakes
The DNR supports the careful experimental control of zebra mussels in situations that will help us evaluate the potential impacts. The DNR does not yet support widespread chemical control of zebra mussels using pesticides due to potential environmental and ecological concerns. We define experimental control as a pilot project aimed at testing new and promising methods in both adaptive management and research. All projects involving the control of zebra mussels are permitted through the DNR.
- What are we learning?
- Zebra mussel control and eradication efforts are difficult due to zebra mussel biology.
- If zebra mussels are found early and isolated, it may be possible to kill all the zebra mussels using pesticides.
- Long term control has not been achieved with partial lake treatments due to challenges in zebra mussel detection.
- Formulations of copper (EarthTec QZ®) are the most cost-effective pesticide to date and can be applied to kill adult zebra mussels and veligers.
- Zebra mussels may be controlled at much lower copper concentrations than previously thought, although nontarget impacts were still observed.
- Ongoing research
Within the last decade, there have been considerable advancements in the research and technology relating to the control of zebra mussels. The DNR continues to evaluate the cost-benefit of zebra mussel control as new information becomes available. We continue to partner with the Minnesota Aquatic Invasive Species Research Center (UMN) and other researchers to evaluate control methods. Some areas of interest that require further evaluation include:
- Nontarget impacts of copper (such as with fish, invertebrates, macrophytes, zooplankton, phytoplankton)
- Long term population control (such as veliger suppression)
- Whole lake treatments
- Incorporating new tools to improve search detectability (such as eDNA)
- MAISRC Copper-Based Control: Zebra Mussel Settlement and Nontarget Impacts
- Alternatives to nonselective copper treatments (such as RNA interference or “RNAi”)
- What experimental control projects will the DNR permit?
The DNR will continue to permit projects on a case-by-case basis. The DNR would encourage projects that build upon the existing knowledge and research of zebra mussel control.
Contact your area invasive species specialist to discuss your potential project.
Projects are more likely to be permitted in situations where:
- there has been initial discussion about your proposal with an invasive species specialist
- the project will offer significant new knowledge of zebra mussel control
- the monitoring and/or project design is sufficient to evaluate outcomes and ‘success’
- the project is likely to have acceptable nontarget impacts
- the water body has been surveyed according to an established monitoring protocol
- there are sufficient resources or partners (e.g., watershed districts, local units of government, lake groups) available to fulfill monitoring requirements and project implementation cost*
*some DNR funds may be available for experiment control projects