From Milton Courier, April 15, 2019

Although an invasive species, zebra mussels are not foreign to many of Wisconsin’s lakes and waterways, and Lake Koshkonong is no exception. The aquatic creatures were first documented in the lake in 2009, Wisconsin Department of Natural Resources Aquatic Invasive Species Coordinator for the south central region Susan Graham said.

The creatures arrived into the Great Lakes system in the mid-1980s, she said.

They were identified in Rock Lake, near Lake Mills and upstream from Koshkonong, in 2005, she added.

“We knew it was only a matter of time before they were in Koshkonong. They were in pretty great numbers on piers a couple of years ago.” With Indianford located just a few miles downstream along the Rock River, it was not surprising, she said, that they would be found there, too.

Still, Edgerton resident George Wellenkotter was surprised, he said, when his hands became cut while helping to remove debris taken by backhoe from the Indianford Dam powerhouse trash racks last month.

Upon closer inspection of the debris, he said, he saw what he believed were several zebra mussels attached to a log.

After viewing photographs of one of the specimens, DNR Statewide Aquatic Ecologist Lisie Kitchel identified the creature as a zebra mussel.

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