WINNIPEG — The Manitoba government says monitoring has shown a significant increase in the number of zebra mussels in Lake Winnipeg and the Red River.
A Conservation and Water Stewardship news release says the province, boaters and the public have been finding significant numbers of zebra mussels on boats along beaches and on infrastructure such as swimming buoys, docks and ladders.
They’ve also been found at the St. Andrews lock and dam.
The freshwater mussels, which are not native to western Canada, have been spreading around the world.
They clog pipes at water treatment plants and can also increase algae blooms in lakes, which can kill fish and wildlife.
Zebra mussels were discovered in Lake Winnipeg in October 2013 and have been found in lakes in popular recreation areas in the United States and in Alberta.
Both Manitoba and Alberta have enacted legislation requiring inspection of boats in transit.
In June 2014, Manitoba declared victory over zebra mussels after a unique experiment which doused four infested harbours with liquid potash. The harbours were initially declared mussel free, but they soon came back.
Boaters found possessing zebra mussels may be fined or prosecuted under the federal Fisheries Act.
Experts have suggested zebra mussels would devastate Manitoba’s $500-million commercial and recreational fishery if they take hold, and could have a $75 million impact in Alberta and $28 million in B.C.
A conference in Richmond, B.C., heard earlier this year suggestions that the mussels may be coming in with Canadian snowbirds towing pleasure boats back to Western provinces from winter getaways in the United States.