Zebra mussels haven’t been an issue in Christina Lake, so far, but even as boating season winds down people are being asked to be vigilant to stop the invasive species from taking up residence.
The Christina Lake Stewardship Society released an information bulletin in the community’s Aug. 24 E-blast detailing how people can identify both zebra and Quagga mussels, why they are a problem and what people can do to help prevent their spread to the lake.
Zebra and Quagga mussels are small bivalve mollusks that grow in clusters, explained Lyra Tuck, stewardship coordinator for the Christina Lake Stewardship Society. Zebra Mussels are native to the Black Sea, arriving in the ballasts and hulls of international ships. They grow to about the size of a human fingernail and have been steadily spreading across Canada and The United States since they were first detected in the 1980s.
Quaggas are a more recent introduction. Showing up in the late 2010’s.
So far they haven’t been detected in lakes or rivers in B.C. or States neighbouring it, Tuck said, but the waters of Christina Lake are monitored and the province and federal enforcement inspect watercraft for signs of the mussels or their larvae.
“The Christina Lake Stewardship Society does monitoring on the lake here every second Friday and we go to Texas Creek and we do veliger (larvae) sampling,” she said. “They are a bivalve, meaning they are filter feeders and people hear that and think ‘great, clear water,’ but that isn’t always a good thing because that means light can penetrate deeper and kill plantlife.”
She added the sampling isn’t preventative because once they are found, little can be done to stop the spread. Monitoring Christina Lake is of great importance because it’s a tourism hotspot and would be an early warning for other regions if mussels were to be found.
Once the mussels are established, they multiply rapidly and can completely change an ecosystem, said Tuck. They have virtually no predators in this part of the world because they are highly toxic as they absorb bacteria and toxins from the water. They also are a hazard to humans because they can clog up water pipes and their discarded shells are very sharp and can slice flesh if someone steps on them.
The Society gathers samples in the lake by placing tubes in the water to see if any larvae have taken up residence. Samples are sent to a lab in Vancouver. The Society receives funding from the province to collect samples and host public education sessions.
There have been several public outreach sessions this season and the response from the public has been overwhelmingly positive, said Tuck.
“People are genuinely concerned about these mussels and what they can do to stop them from spreading,” she said.
One hot topic is how to tell the difference between invasives and native mussels. A big difference is their size and how they grow. Native mussels often grow to around five centimetres, are alone and dig into the strata while zebra and quagga mussels are always in clusters and stick to surfaces.
The other is what people can do to stop the spread. Tuck said the province and Society pushes the “Clean, Drain, Dry” mantra for boaters, where they are encouraged to inspect and disinfect their boats, drain ballasts, live wells, engines and props and thoroughly dry everything after being in the water.
American Customs and Border Protection and Canadian Border Services agents are trained to look for mussels and have the authority to seal a boat, preventing the owner from launching it.
Inspection stations are set up on Canada’s highways where people can pull in and have their boats looked at for free, Tuck said. From what she’s been told, most people comply.
If someone has had their boat in infested waters, they can be disinfected, but another method is to keep it drained and dry for at least 30 days to kill any larvae or mussels.
If you do find something that you think may be an invasive Zebra or Quagga mussel, you can either contact Christina Lake Stewardship Society at CLSS@shaw.ca or (250) 447-2504 or report it to the B.C. Conservation Officer Services Hotline at 1-877-952-7277 (RAPP).