Zebra mussels have moved north of the border. Manitoba officials are trying to determine the scope of an infestation discovered recently in Lake Winnipeg.
It's not known how the zebra mussels reached the world's tenth largest freshwater lake, but the Red River flows north into the lake, bringing water from Minnesota lakes where zebra mussels are established. Zebra mussels have not been confirmed in the Red River, but veligers, the immature mussels that float with the current, have been found in the river.
It's also possible (and perhaps more likely) that anglers traveling north to fish Lake Winnipeg carried the zebra mussels with them on their watercraft or equipment.
Manitoba is now implementing a boat inspection program at the U.S.-Canada border and adding boat decontamination units to clean boats entering Manitoba at border crossings.
Manitoba officials are concerned zebra mussels will add to the existing problems caused by large amounts of phosphorus and nitrogen pollution flowing into Lake Winnipeg. A significant amount of that pollution comes from the Red River.
Pollution causes massive algae blooms each summer, and threatens the lakes fish populations.
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