Parks Canada preparing to isolate cove in Manitoba where zebra mussels were found

A containment curtain is expected to be installed next week in Clear Lake as Parks Canada officials hope to prevent the spread of zebra mussels.

Last week, Parks Canada said an adult zebra mussel was found in the part of Clear Lake known as Boat Cove.

"Parks Canada snorkelers found on partial shell and one living, adult-sized zebra mussel attached to a rock," Parks Canada previously said in a news bulletin.

The next step for officials is to hopefully prevent the spread of the mussels outside of the cove.

This means a containment curtain will be set up – stretching from the cove to the pier. Parts of the curtain have already arrived, with the remaining pieces set to show up on July 29 and a dive team will immediately start deploying the curtain.

"This work is being done in preparation for a potential eradication method," said Dameon Wall the external relations manager with Parks Canada. "However, I must stress that at this time a decision about whether to proceed with an attempted eradication has not been made. Parks Canada is awaiting the results of further visual surveys and water sampling from other areas of the lake, before determining the best course of action."

Wall said if the mussels have been contained, the goal is to treat the area with potash and eradicate the mussels.

Tim Town, the ecologist team lead for Parks Canada, said if this is the eventual path they take, it is quite an effective treatment.

"They've done quite a bit of testing in regards to the effect on other species, and it's fairly targeted, especially at the concentrations that would be required for treatment in our case," said Town.

He said they would need 100 milligrams per litre and at that level, it would only target freshwater mussels.

Wall noted if the zebra mussels have spread beyond the cove, then potash treatment would become less effective depending on how far they have spread.

Town said to date, no other samples from the lake have come back with any indications of zebra mussels other than in the Boat Cove area.

"We're pretty confident that things are still fairly isolated in terms of the establishment of zebra mussels," said Town. He did note, however, that they are still waiting for around 78 test results to come back.

Wall is reminding people that no watercraft are allowed in Clear Lake, and no matter what body of water people go to, rules have to be followed.

"The requirement under provincial rules is that you have to clean, drain and dry stuff before you leave the site, and certainly before it gets into any other water body," said Wall. "Minimizing the potential spread is everybody's responsibility."