Zebra mussels now found in Lake Winnipeg’s north basin

The Nature Conservancy of Canada believes the lake needs our help more than ever, and warns that more invasive species could be on the way.

Students in Zoology 315, a popular limnology course taught by UW-Madison Center for Limnology (CFL) Professor Jake Vander Zanden, found the hard-shelled animals while participating in a laboratory session this October. Zebra mussels feed on the suspended algae needed by other organisms and this disruption to the food web may limit survival and growth in fish.

“Zebra mussels are known to be in less than 5 percent of the lakes in Wisconsin that have been identified as suitable for them”, said Bob Wakeman, DNR aquatic invasive species coordinator.

The mussels also concentrate a lake’s nutrients along the bottom, dramatically changing ecosystem dynamics, and can clog intake valves. “Lake Winnipeg has a real opportunity, because where I’m from in Ontario, in the Great Lakes, there are over 200 invasive species”. The scientists are also working with the Wisconsin Department of Natural Resources to manage these invaders.

Of the 24 samples collected during the fall Lake Winnipeg monitoring program, one zebra mussel veliger was found in a single water sample collected southeast of George Island.

“It’s really important to make sure we are not transporting water from one lake to another because they have microscopic larva”, Vander Zanden said.