Waterways threatened by zebra mussels

CHESTERMERE, Alta — It takes only two cups of water to spread zebra mussels, an invasive creature that plugs up infrastructure and eats other aquatic animals out of house and home.

Programs across Canada and the United States are urging boaters and fishers to clean, drain and dry their equipment before moving from one lake to the next.

“Invasive aquatic species are potentially one of the biggest threats to our fresh water resources,” says Sharina Kennedy of Alberta’s environment and sustainable resource development department.

Quadra and zebra mussels arrived in bilge water in cargo ships from Europe, and the threat spread when the water was emptied into the Great Lakes in the 1980s.

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States such as Idaho have developed major inspection stations, tracing where equipment came from and where it is going. They focus on boat traffic, fishing gear, float planes and aquaculture operations.

Inspection stations have found boaters were destined for eight lakes in Alberta. Most recently, inspectors intercepted a boat destined for Chestermere Lake east of Calgary.

“That boat turned out to be mussel fouled,” she told an agriculture tour.

A large town has grown up around the reservoir, which is part of the Western Irrigation District. The dangers to agriculture are significant because the mussels reproduce so quickly.

Mussels that entered the Bow River could quickly move downstream and into irrigation networks, dams and hydroelectric systems.

Zebra mussels looks like a striped clam.

They can survive out of water for 30 days and are capable of laying a million eggs a year. They start out as microscopic larvae and are producing eggs by six weeks of age.

There is no feasible control, and the mussels cannot be eaten because they produce a toxin.

Besides gluing themselves to infrastructure and other animals, the mussels also consume the plankton and algae used as food by native species. The result is a clear water body that does not support life.

However, they seem to avoid blue green algae.

“Where there are mussels there are often blue green algae problems,” Kennedy said.

They were found in Lake Winnipeg last year, but treatments of liquid potash and other chemicals appeared to kill the larvae. None were found this summer, according to Manitoba Conservation.

Those who find attached mussels on boats or other water equipment may report them to 855-366-BOAT.

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