Researchers at the Minnesota Aquatic Invasive Species Research Center work all around the state to find solutions to aquatic invasive species problems. Here's what's going on at Lake Minnetonka this summer:
Zebra mussel control treatments
In partnership with the U.S. Geological Survey, researchers will use low-dose copper treatments to treat zebra mussel populations in St. Alban's Bay. Robinson Bay will be monitored as a control reference. This treatment specifically targeted zebra mussel larvae (veligers) because the amount of copper required to kill them is significantly lower than what is required to kill adults. Larval suppression could be a very useful technique to suppress overall populations. They will also be evaluating the impacts of these treatments on non-target species like native zooplankton, benthic invertebrates, and fish. The treatment occurred in July, and the last sampler plate will be removed in October. Data will be evaluated over the winter, with results expected in early summer 2020. Learn about other zebra mussel research going on at MAISRC -- including sequencing the zebra mussel genome! -- here.
Developing common carp removal schemes
Based off years of foundational common carp work in the Lake Minnetonka subwatershed, researchers are working this summer to develop new ways to effectively and selectively remove invasive common carp from Lake Minnetonka. Previous research has shown that carp can be selectively attracted with food to form large aggregations that can then be removed with special, high-precision nets. However, to make these nets more effective, scientists are researching how to maximize carp foraging aggregations using two key social learning strategies: increasing access to bait to allow both frequent visitors (often “bold”) and infrequent visitors (often “shy”) to participate in foraging aggregations, and releasing individuals that might bring other carp to the aggregation. Field work will be conducted in Halstead's Bay. Learn about other common carp research going on at MAISRC here.
Starry stonewort early detection
Early detection is critical when it comes to the control of starry stonewort. Lake Minnetonka will be surveyed for this invasive alga as part of Starry Trek on August 17. Starry Trek volunteers found starry stonewort in Grand Lake in 2017, which led to the lake association and Minnesota DNR rapidly mobilizing to hand-pull the infestation. This early intervention was successful, with starry stonewort now under control in the lake. Click here for information about participating in Starry Trek.
Improving Eurasian and hybrid watermilfoil management
Hybrid watermilfoil, the child of native Northern watermilfoil and invasive Eurasian watermilfoil, was confirmed to be in Lake Minnetonka through genetic verification that MAISRC conducted in the summer of 2018. This summer, research will be conducted to assess the response of hybrid watermilfoil to herbicide treatment, and pilot a new herbicide challenge-screening of hybrid watermilfoil. Together, these will improve management efforts for this invasive plant. Field work will be conducted at Gray's Bay, Smith's Bay, and North Arm. Learn more about other Eurasian and hybrid watermilfoil research going on at MAISRC here.