Zebra mussels found in lake near Cannon Falls

CANNON FALLS, Minn. — Zebra mussels, an invasive species, have been found in a lake south of the Twin Cities.

According to the Minnesota Department of Natural Resources, staff members found one adult zebra mussel in Lake Byllesby in August of 2023. At the time, officials say there were no other zebra mussels or signs of reproduction.

This summer, staff members found four zebra mussel larvae, which indicated that they were reproducing in the lake.

Native to eastern Europe and western Russia, zebra mussels were unintentionally introduced to the Great Lakes system through contaminated cargo ship ballast water which was discharged, the DNR said. They were first discovered in 1988.

They are small with striped, D-shaped shells that are roughly a quarter of an inch to half an inch long.

The DNR says Minnesota law requires people to clean watercraft, drain water and dispose of unwanted bait in the trash to help slow the spread of the invasive species.