Destructive, invasive freshwater species detected near east coast

Zebra mussels, an invasive species that kills native mussels and chokes drinking water systems, have been discovered in the Saint John River in New Brunswick, the farthest east in Canada they've been positively identified.

Fisheries and Oceans Canada said last week in a release that environmental DNA tests over the summer had detected the presence of the small Eurasian freshwater mussels with the telltale striped pattern in parts of the river as far apart as Edmundston, Grand Falls and Nackawic, communities that span more than 200 kilometres.

Volunteer monitors from Société d'aménagement de la rivière Madawaska also saw and collected what they thought were zebra mussels along a hydroelectric dam in Edmundston. The dam is on the Madawaska River, about 40 kilometres downstream from Lake Temiscouata in Quebec, near the border, where the invasive molluscs were detected last year.

Lab tests in late August confirmed the bad news: the destructive zebras had arrived in New Brunswick.

"The zebra mussel damages and wreaks havoc on Canada's freshwater ecosystems,” said Diane Lebouthillier, the federal fisheries minister, in the release. “We're building a strong regional network that provides scientific and technical support to combat these invasions."

Ottawa, she said, was working with provincial, municipal, non-governmental and Indigenous partners to monitor New Brunswick's lakes and rivers for any new presence of aquatic invasive species.

Every year, zebra mussels cause millions of dollars in damage in Canada by clogging intake pipes and other important parts in power stations and water treatment plants, and by damaging boats. If enough of them attach to navigational buoys and floating bridges, their accumulated weight can sink them.

The invasive species is thought to have arrived in the Great Lakes in the 1980s from ballast water released by large ships from the Black Sea in Europe. According to the U.S. Geological Survey, they have spread rapidly throughout the Great Lakes and into the large rivers of the eastern Mississippi drainage. They have also been found in Texas, Colorado, Utah, Nevada and California.

They were first detected in Ontario in 1988 and have gone as far west as Lake Winnipeg and as far east as Nackawic.

They are particularly harmful to native mussels, many of which are species at risk. Zebra mussels hog their food, such as plankton, and attach themselves to native mussels, suffocating them.

Earlier this year, the federal Liberal government created the Aquatic Invasive Species Prevention Fund, backed with nearly $8.8 million over five years, to help combat the problem. The nonprofit group Organisme de bassin versant du fleuve Saint-Jean and its partners are using the program to introduce a plan to limit the spread of zebra mussels throughout the Saint John River watershed.

New Brunswick and Quebec volunteers will map areas most vulnerable to the presence of zebra mussels and work on setting up a network of boat washing stations in key locations. The larvae of the mussels are microscopic, float in the water and follow the currents of lakes and rivers until they attach to a solid surface, making them difficult to detect.

The release stated the stations would teach boaters how to stop the spread of zebra mussels by cleaning, draining and drying their watercraft. In addition, a public education and awareness campaign on best practices to control the spread of the invasive species will be launched.

DFO is encouraging the public to be vigilant, learn how to prevent the spread of zebra mussels, and report any sightings to the federal department or the New Brunswick Invasive Species Council.

It also warns that eating zebra mussels is not recommended because they accumulate toxins as they filter water.

John Chilibeck, Local Journalism Initiative Reporter, The Daily Gleaner