Local groups receive grants to monitor invasive species
By: By Emily Kram, Superior Telegram
In 2007, curly leaf pondweed and Eurasian water milfoil were detected in the St. Croix Flowage near Gordon. Rapid action was taken to eliminate the outbreak by the Wisconsin Department of Natural Resources and local lake associations and interest groups.
The milfoil was treated and mostly removed, but Scott Peterson, executive director of Friends of the St. Croix Headwaters, said the area still must be monitored closely for the invasive plant.
“It is like a chronic disease,” Peterson said. “Once you have it you can never get rid of it.”
This summer, the St. Croix Headwaters group will continue its monitoring efforts thanks to a $10,000 DNR River Planning grant it received in July to fund an aquatic invasive species (AIS) study.
“The project is designed to address one of Wisconsin’s most immediate aquatic invasive species study needs, which is monitoring along our flowing waters to increase our understanding of the spread of invasive species through these corridors and how they are impacting river and stream ecosystems,” Peterson said.
Matthew Berg, a biology teacher at Grantsburg High School, will lead efforts to conduct an aquatic plant survey. He and his students have worked with the St. Croix Headwaters group before to conduct a mussel study last year. According to Peterson, survey work will be done on the St. Croix River between Upper St. Croix Lake at Solon Springs and the St. Croix Flowage at Gordon.
“In addition, the work will include a section of the St. Croix National Scenic Riverway directly downstream from the Gordon Dam,” Peterson said. “This area has a chronic Eurasian water milfoil (problem), which while small, is proving difficult to completely eradicate.”
The St. Croix Headwaters group is partnering with the River Alliance of Wisconsin and Douglas County AIS Coordinator Amy Eliot on the project.
“The important thing about a plant survey is it tells not only what invasive species are there, it also shows the native plants and overall health of the ecosystem,” Eliot said.
Eliot, who works with the Lake Superior Research Institute based at the University of Wisconsin Superior, will undertake another water monitoring program in Douglas County this summer, also funded by a Wisconsin DNR grant. The funding for Eliot’s project comes from the Aquatic Invasive Species Education, Prevention, & Planning Program. She will work with assistant Josh Horky to determine if about half a dozen invasive species are present in local waters.
In the next two or three months, Eliot plans to check at least 12 local lakes for a variety of invasive plants and animals. Among the invasive species she will test for are: rusty crawfish, mystery snails (which come from Europe and Asia), zebra mussels, spiny water fleas, curly leaf pondweed and Eurasian water milfoil. All have been confirmed in Wisconsin inland lakes, with Eurasian water milfoil the most common infector.
“I think we need to act now,” Eliot said. “We are situated between southern lakes that already have a lot of these invasive species, but we also have Lake Superior at our northern doorstep, which (harbors) invasive species.”
Because of her past work with the Wisconsin DNR, Eliot feels strongly that lakes should be available to all for use. At the same time, she expects those who enjoy the lakes to also be stewards of the waters. Small things like cleaning boats carefully after use and eliminating phosphorus runoff from lawn fertilizer on lakefront property can have a large cumulative effect.
“If humans stop and take a look at their equipment, maybe we can prevent the spread (of invasive species).” Eliot said.
Elsewhere in the Northland, the prevention battle has already given way to the crusade to exterminate.
Since early this spring, the Upper St. Croix Lake Association has been rearing beetles of the genus Galerucella to use as a biocontrol for purple loosestrife. The small, brown or amber-colored beetles feed only on purple loosestrife and can dramatically reduce the population of the invasive plant over time.
Lynne Nason, with the Lake Association, has been monitoring the beetles as they develop in an enclosure outside of the Solon Springs Mercantile. She said they should be ready to transport to problem loosestrife areas within a matter of days.
After the adult beetles are relocated, they feed on the purple loosestrife before burrowing into the ground to spend the winter. When the snow melts, the beetles reemerge and produce larva that feed on the loosestrife foliage, and the cycle continues.
Around Upper St. Croix Lake and in the ditches around Solon Springs, the Lake Association seems to be winning its battle. Nason has noticed purple loosestrife is no longer present in areas it had once taken over, and she is hopeful the invasive plant can now be held in check.