Zebra mussel discovery in N.B. triggers meeting of scientists

Shane Fowler · CBC News

· Posted: Mar 18, 2025 1:42 PM EDT | Last Updated: 9 minutes ago

The find of a azygous big zebra mussel successful the St. John River sparked a caller gathering of scientists and researchers who knew the find was each but inevitable. 

The invasive mussel was recovered connected a floating dock pulled up successful Mactaquac successful December, and the fig could easy go millions successful a fewer years, scientists said. 

"If they've taken clasp successful important numbers they're astir intolerable to eradicate," said Terry Melanson, the squad pb with the aquatic invasive species program with the Department of Fisheries and Oceans.

"You cannot eradicate them erstwhile they're successful the system, that's been the acquisition truthful far."

That's wherefore much than 60 representatives of watershed groups and assorted authorities agencies and departments, including the Federal Department of Fisheries and Oceans and N.B. Power, met successful Fredericton for a day-long strategy session organized by the New Brunswick Invasive Species Council.

"We're besides getting everyone up to day connected what the concern is present successful New Brunswick and what's being done currently," said Sarah Cusack, task co-ordinator with the council. 

WATCH | How 1 tiny mussel successful the St. John River could perchance outgo millions: 

It whitethorn beryllium excessively precocious to forestall zebra mussels from inhabiting the St. John River, but it's not excessively precocious to forestall the mussels from taking implicit different large New Brunswick waterways, the gathering was told.

Zebra mussels are a highly invasive taxon that reproduce rapidly and tin alteration an ecosystem if the mussel get a foothold.

The mussels' crisp shells tin disrupt beaches and swimming areas. High numbers successful intakes tin clog up infrastructure specified arsenic hydroelectric dams and drinking-water systems.

And populations of millions of zebra mussels tin filter nutrients retired of waterways, denying these to section species.

Numbers shared by the Department of Fisheries and Oceans amusement that successful 2022, zebra mussel colonies in Lake Témiscouata in southeastern Quebec, astir 300 kilometres upriver from Mactaquac, were recorded astatine astir 150 mussels per quadrate metre.

That fig grew to 2,500 successful the aforesaid country successful 2023, and to 35,000 per quadrate metre past year.

Studies person looked astatine the outgo of allowing zebra mussels into waterways, which would beryllium higher than the outgo of keeping them out, the meeting heard.

In British Columbia, for example, the outgo would beryllium an estimated $64 cardinal to $129 cardinal annually if the mussels were to beryllium introduced into the province, said Martina Beck, portion caput with the provincial Ministry of Water, Land and Resource Stewardship.

She gave a presumption to the radical successful Fredericton about the costly interaction of zebra mussels on municipal h2o supplies, hydro power, agriculture, irrigation systems, tourism and spot values.

"We surely cognize that the outgo of preventing their instauration is acold little than what it would outgo to code them erstwhile they've established," Beck said. 

B.C. has focused connected prevention and adopted authorities that asks boaters to drain their boats oregon look a $400 fine. The state has besides retained a brace of canine units trained to sniff retired the invasive taxon connected boats being transported. Both are strategies that could beryllium considered successful New Brunswick, Beck said. 

In New Brunswick, a nationalist "Clean, Drain, Dry" run for transporting boats overland volition ramp up, but the state has been little assertive than B.C.

Boat lavation stations successful Edmundston, Nackawic and Mount Carleton Provincial Park person been built successful effect to the zebra-mussel detection successful Quebec, with more planned for this summer. But there's been nary authorities to get boaters to enactment to support the invasive taxon astatine bay.

"It's each messaging that's hoped to beryllium taken up arsenic a 'Do it yourself' benignant of thing," Cusack said. "From my knowing there's nary enforceable facet to that."

Signs of penetration 3 years ago

Charles-Oneil Crites, a chemistry prof astatine the University of Moncton field successful Edmundston, has been studying the h2o coming into the St. John River system. Two years ago, helium estimated millions of zebra mussel larvae were flowing into the state from the colonisation discovered successful Lake Témiscouata in 2022. 

"There was 300 cardinal individuals exiting the Madawaska River, going into the St. John River, each day," said Crites. "That means determination is simply a important magnitude of larvae that could perchance settee somewhere." 

What fig of those larvae volition beryllium capable to connect to an area, mature and reproduce is simply a "probability game," according to Crites, who said larvae tin look one-in-a-million odds, depending connected the situation they find.

Briskly flowing rivers alteration the odds, and calmer waters often summation them. While the St. John River volition apt spot an summation of zebra mussels successful the years ahead, Cusack said, it's not excessively precocious to forestall zebra mussels from hitchhiking to other rivers and lakes and colonizing them.

"The St. John River, yes, [zebra mussels] are going to dispersed done naturally," Cusack said. "The happening that's not people going to hap is it getting into the Miramichi River, the Restigouche River, different systems that are not connected to the St. John."