Parks Canada monitoring for zebra mussels

Parks Canada says genetic traces of zebra mussels found in a recent water sample taken from Clear Lake aren’t cause for undue concern.

Although tests for environmental DNA for the invasive species came back positive last month, it could have come to the lake on a boat, water toy or other source, without the transfer of any living mussels.

Living organisms like zebra mussels, which originated from the lakes of southern Russia and Ukraine and were introduced to many countries worldwide in the 1980s, shed DNA all the time, says Borden Smid, resource conservation manager with Parks Canada.

“It’s something that occurs naturally in the environment with living organisms,” Smid said.

Similar situations have resulted in waters being tested for zebra mussel environmental DNA for many years, and is more of a red flag to be on the lookout for future problems rather than an indication that zebra mussels have gained a foothold in the lake, located 100 kilometres north of Brandon in Riding Mountain National Park.

The sample in question was taken during a regular monitoring check over the August long weekend last year. One of three samples taken that day came back signaling the presence of DNA from zebra mussels.

“But it doesn’t mean a zebra mussel was in the water,” Smid said. “If we did have boats that were from areas around Manitoba, that come to Riding Mountain … and if they came from a water body that had zebra mussels in it, there’s just DNA floating around in that water as well.”

Zebra mussel DNA can adhere to boats, air mattresses and even lifejackets. To get rid of these trace elements of DNA, bleach would need to be used.

But even though parks officials aren’t too concerned about the presence of zebra mussel environmental DNA in Clear Lake, they began increasing monitoring and testing for the invasive species by working closely with Fisheries and Oceans Canada, Ontario and Prairie Region, and the provincial government on Feb. 20.

Parks Canada is also planning to work closely with Keeseekoowenin Ojibway First Nation, businesses and tourism stakeholders and environmental non-government organizations during the testing process, said Dameon Wall, Riding Mountain National Park’s external relations manager.

“We want to definitely have them by our side as we’re starting those conservations,” he said.

The Sun contacted Keeseekoowenin Ojibway First Nation but did not receive a reply by press time.

“We’ve got a whole bunch of sample sites that they’re going over … until the ice comes off. We’ll be going over them every other week, collecting samples and doing testing to see if we get more hits of DNA,” Smid said.

Parks Canada is also looking at whether they need to do more stringent inspections of boats. Smid said Parks Canada has been holding consultations to ensure people understand that testing will have to go on for awhile. In the meantime, Parks Canada is asking people to stay away from the research and dive sites on Clear Lake where testing is going on.

“We will have to test for a while, and if we keep getting negative … then eventually the lake will be clear,” Smid said.

Education is an important part in ensuring that zebra mussels don’t ever become a part of Clear Lake’s ecosystem, as they have in Lake Winnipeg. Although Parks Canada has always tried to teach swimmers and boaters about the importance of watching out for the invasive species, more awareness can only be a good thing, Smid said.

“I think we want to have a bit more presence on the beach at Clear Lake, so people are a bit more aware of what needs to be done,” he said. “There’s always something else we can do in terms of informing the public.”

This is not the first time genetic traces of zebra mussels have been found in the national park. Traces were detected in Whirlpool Lake in December 2017. The lake and its campground were closed for all of 2018 as a precautionary measure.

The best way for boaters to prevent the spread of zebra mussels is the “clean, drain, dry” process, in which boaters inspect and clean watercraft and any gear, grain any sitting water and let them dry completely between trips.

» mleybourne@brandonsun.com, with files from the Winnipeg Free Press

» Twitter: @miraleybourne