International scientists meeting at the Invasive Species Council of B.C. on Tuesday said zebra and quagga mussels can be sneaky stowaways that have the ability to devastate waters where they're not indigenous.
Colonies of the mussels not only pose risks to fishing and biodiversity but are known to clog pipes and cause major problems for hydroelectricity and irrigation infrastructure, the conference heard.
Economic impact studies suggest the annual cost associated with an infestation could amount to $75 million in Alberta and, based on more conservative criteria, $28 million in B.C.
Though British Columbia, Alberta and Saskatchewan currently remain free of the unwanted creatures, experts warned that Canada's patchwork of strategies and regulations must be strengthened.
B.C. is leading the work to confront the problem nationwide, but has had to rely heavily on a "loose collaboration" with authorities in the U.S., said council chairman Barry Gibbs.
He said Idaho has a nearly decade-old boat tracking program and mandatory inspection system.
"They've created maps, and that's probably what's scared the hell out of all of us," Gibbs said. "Because those maps show that the boats are going and coming, just through Idaho, from all Canadian provinces in the West and all over the U.S.
"These boats are travelling everywhere. It's staggering."
Gibbs and other experts at the conference are pushing for the passage of draft federal regulations, under the Fisheries Act, to give Canada's border agents the power to inspect and quarantine boats returning from contaminated waters.
Lake Mead in Nevada, at the base of a northbound highway route, is one of the biggest culprits, he said.
The regulations would apply to the zebra and quagga mussels, as well as three species of invasive Asian carp. If passed as early as this spring, the Canada Border Services Agency could start enforcement immediately.
Jodi Romyn, senior manager with the council, said the regulations and associated training for agents would form a broad net.
"They're a line of defence that can speak to that issue, regardless of what (the species) is," she said.
The porous border was made especially evident just last year, the council members said, pointing to the discovery that zebra and quagga mussels had found their way into Lake Winnipeg.
They credit a made-in-B.C. plan initiated in 2012 for staving off the species' introduction so far, including the interception of a contaminated commercial vessel before it was anchored in Shuswap Lake.
Together with the provincial Environment Ministry they worked to protect the lake, at the heart of the south-central region, which connects with a vast network of rivers and streams. B.C. already has its own legislation that includes a more fulsome list of invasive species.
"Based on monitoring, we haven't found any (mussels) so we believe those efforts were successful," Romyn said, adding that in 2014 alone B.C. managed to halt 10 commercial boats that were identified as originating from infested areas.
The experts said invasive species are an ongoing threat and that interprovincial collaboration must be strengthened. Boat owners can take their own action simply by cleaning, draining and drying their boats if they plan to transfer a craft from one water body to another in less than 30 days, after which point the mussels die.
Measures for early detection and rapid response to an infestation appear well in hand on the local level, said conference presenter Mike Ielmini with the U.S. Department of Agriculture's Forest Service.
"At the big scale we're having trouble with this," he said. "We don't have the same concept in invasives as we do with homeland security issues or fire issues or human health issues."
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