Zebra mussels not welcome but won’t doom Lake Sarah

DNR Invasive Species Specialist Allison Gamble shows a sample of how zebra mussels can attach themselves to a native mussel. This sample was taken from the Mississippi River. Gamble was in Murray County last week.

By Per Peterson

The last thing Department of Natural Resources officials want to deal with is invasive species in a Minnesota lake. However, the recent discovery of zebra mussels in Lake Sarah, as disheartening as it is, is not a death sentence for the popular fishing and recreation lake.

“I think we would expect to see them expand in Lake Sarah for a while and then hope the population takes a dive,” DNR Invasive Species Specialist Allison Gamble told a small audience that gathered last Thursday at the DNR lake access on the west side of Lake Sarah. “It’s certainly not like the lake is doomed. The lake will be fine.”

Still, once zebra mussels — freshwater mussels not native to Minnesota — are introduced to a lake, it’s virtually impossible to eliminate them. They can be controlled with a pesticide that was approved for open-water use in 2016.

“It’s very new and the research is still ongoing in terms of trying to control them in spot treatments,” she said. Gamble said zebra mussels are the only mussels in Minnesota that will attach to solid structures — from docks and lifts, buoys and sticks, to larger, native mussels. They can change the ecology of the lake by sucking in particles in the water to get the food source out, and then eliminating the clear water.

“It’s the same food that juvenile fish would eat,” Gamble said.

For more on this article, see this week’s Headlight-Herald.