(Canadian Press)

Spread of invasive species in Canada costs billions, changes environment

Experts say the plight of the spotted frog is one of many examples of how invasive species can overtake an area

For two decades experts have been carefully nursing a community of endangered northern leopard frogs in B.C.’s Kootenay region but invasive bullfrogs and fish threaten to muscle in, potentially swallowing years of work.

Purnimia Govindarajulu, a small mammal and herpetofauna specialist at B.C.’s Ministry of Environment, said disease and invasive fish already mean the endangered frogs aren’t thriving as they should be in a wetland in Creston.

More concerning to her is that a mass of bullfrog eggs was recently missed in a lake just 15 kilometres away, and Govindarajulu said teams in Canada and the United States are preparing to do battle with the voracious bullfrog to prevent its spread.

“We call it the American bullfrog action team,” she said, lowering her voice with mock authority.

“The defenders of the northern leopard frog,” she added with a chuckle.

Bullfrogs are native to parts of Central and Eastern Canada and are even on the decline in some areas, but they have overtaken parts of southern B.C. and are known to eat native fish, frogs, salamanders, snakes, birds and turtles.

Experts say the plight of the spotted frog is one of many examples of how invasive species can overtake an area, squeeze out existing plants or animals, create a lasting scar on the landscape and impose huge costs on the Canadian economy.

A common thread to the threat to many of Canada’s species at risk are invasive species, said Gail Wallin, executive director of the Canadian Council on Invasive Species.

“So not only do invasive species take over our natural environment, they actually threaten species at risk. They have a major environmental impact.”

Invasive species like giant hogweed, zebra mussels and knot weed can overwhelm entire ecosystems, stripping lakes, valleys and cities of wildlife and vegetation.

A 2008 report by the Canadian Food Inspection Agency said there were at least 486 invasive alien plant species alone in Canada.

The cost of battling or holding back invasive species is incalculable, Wallin said, pointing out that every level of government, homeowners, farmers, businesses and other groups spend money on the fight.

The annual economic impacts on agriculture, crops and forestry is estimated at $7.5 billion, she said.

“When we look at these huge economic costs, we have to recognize that we’re only looking at samples, we’re not looking at all the costs of the total number of invasive species in Canada,” Wallin said.

David Nisbet, manager of partnership and science at the Invasive Species Centre in Sault Ste. Marie, Ont., said putting a price tag on the issue is difficult because an invasive species can set off all kinds of actions and reactions. When pests kill trees it can change the oxygen supply, prompt flooding, reshape the neighbourhood canopy and cost homeowners or a city for replacements, he said.

Recent surveys by the centre on spending in Ontario shows an average municipal cost of $381,000 a year.

The Canadian Food Inspection Agency classifies invasive species as plants, animals and micro-organisms in an area where they’ve never been before. They can adapt, spread quickly and don’t have natural predators in their new environment.

Insects like the emerald ash borer, which kills ash trees, have ravaged hundreds of thousands of hectares of Ontario’s forests. Giant hog weed with its highly toxic sap has taken over entire valleys in B.C. and nematodes have had devastating impacts on Canadian crops.

Most invasive species are moved by people, Wallin said, adding that’s where they’re aiming education.

Hogweed was brought in as a garden plant. Firewood moved between campsites also transports pests. Boaters carry Eurasian milfoil or zebra and quagga mussels with them when they change lakes, she said.

Some of the largest factors in the spread and introduction of invasive species are trade and travel, Wallin said. Bugs can hide in untreated pallets and tourists may bring something back intentionally or not.

“We’ve got way more trade coming in now so we need to be more conscious of that. Other countries have new regulations in place, making sure that before you ship into our countries that your cargo is clean of invasive species,” Wallin said.

“We can do more than what we do now. It’s a big world and we’re all travelling. So yes, regulation will be really important.”

The problems spread because people aren’t aware of the risks, said Nisbet.

“They don’t have a negative intent in mind, we should try not to place the blame on Canadians who just aren’t aware, we try to place a lot of effort in raising that awareness.”

Govindarajulu said many people don’t realize it’s illegal to move or remove frogs from their environment and it’s also against the Wildlife Act to bring them back because they could be introducing disease into the rest of the population.

“Often it’s children and often people mean well. It’s not like they’re being vindictive, they want to help frogs and they think they are.”

The Invasive Species Centre runs a citizen science program in Ontario, training those interested to identify a problem before it spreads. Nisbet said the program has been helpful with people reporting their suspicions and findings around the province.

The lesson is to take action, he said.

“Whether it’s cleaning you gear after you go boating, or if you go hiking, cleaning your boots, cleaning your pets, getting all the seeds and plant material off, buying local firewood, buying native plants, just taking these sorts of actions to prevent the spread of invasive species further.”

The Canadian Press

Like us on Facebook and follow us on Twitter.

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

A pair of crashes on Highway 1 between Abbotsford and Chilliwack have snarled traffic in both directions.
Pair of crashes snarl traffic between Abbotsford and Chilliwack

Traffic delays eastbound, large westbound backup

Final numbers won't be known for weeks, but turnout was down across the board in the Fraser Valley and B.C.
Chart: Tyler Olsen
Election turnout down across Fraser Valley and B.C.

Even after thousands of mail-in ballots counted, turnout is likely to fall below 50% in many ridings

NEWS FILE PHOTO
Voters in Chilliwack, Abbotsford, Mission and Langley may head back to polls in 2021

Election of local politicians in BC vote would trigger by-elections in several Fraser Valley cities

(from l) Fraser-Nicola candidates Jonah Timms (BC Green Party), Jackie Tegart (BC Liberal Party), and Aaron Sumexheltza (BC NDP). The polls have now closed and the counting has started. (Photo credit: Submitted)
Results awaited in Fraser-Nicola as polls have now closed

Counting of advance and election day votes has begun; mail-in votes to be counted starting Nov. 6

Fraser-Nicola BC Liberal Party candidate Jackie Tegart with supporters on the Ashcroft bridge, Oct. 21, 2020. Tegart is the frontrunner in the riding after the initial vote count, with mail-in ballots to be counted starting on Nov. 6. (Photo credit: Barbara Roden)
Liberal incumbent Jackie Tegart holds narrow lead over Aaron Sumexheltza of NDP

Initial count is complete, and mail-in ballots will determine who wins in Fraser-Nicola

NDP Leader John Horgan celebrates his election win in the British Columbia provincial election in downtown Vancouver, B.C., Saturday, Oct. 24, 2020. THE CANADIAN PRESS/Jonathan Hayward
Horgan celebrates projected majority NDP government, but no deadline for $1,000 deposit

Premier-elect says majority government will allow him to tackle issues across all of B.C.

This Crescent Beach home, located at 12505 22 Ave., was subject of a police search warrant June 18. (Google image)
Civil forfeiture office alleges $2M Surrey home was used to launder cannabis money

Court documents request the home, and $85,000 to be turned over to the government

FILE – Prime Minister Justin Trudeau greets Premier John Horgan during a press conference at the BC Transit corporate office following an announcement about new investments to improve transit for citizens in the province while in Victoria on Thursday, July 18, 2019. THE CANADIAN PRESS/Chad Hipolito
Trudeau congratulates Horgan on NDP’s election victory in British Columbia

Final count won’t be available for three weeks due to the record number of 525,000 ballots cast by mail

Comedic actor Seth Rogen, right, and business partner Evan Goldberg pose in this undated handout photo. When actor Seth Rogen was growing up and smoking cannabis in Vancouver, he recalls there was a constant cloud of shame around the substance that still lingers. Rogen is determined to change that. (Maarten de Boer ohoto)
Seth Rogen talks about fighting cannabis stigma, why pot should be as accepted as beer

‘I smoke weed all day and every day and have for 20 years’

Provincial Green Party leader Sonia Furstenau speaks at Provincial Green Party headquarters at the Delta Victoria Ocean Pointe in Victoria. (Arnold Lim / Black Press)
VIDEO: Furstenau leads BC Greens to win first riding outside of Vancouver Island

Sonia Furstenau became leader of BC Greens one week before snap election was called

Join Black Press Media and Do Some Good

Pay it Forward program supports local businesses in their community giving

NDP Leader John Horgan elbow bumps NDP candidate Coquitlam-Burke Mountain candidate Fin Donnelly following a seniors round table in Coquitlam, B.C., Tuesday, October 20, 2020. THE CANADIAN PRESS/Jonathan Hayward
Horgan, NDP head for majority in B.C. election results

Record number of mail-in ballots may shift results

RCMP crest. (Black Press Media files)
Mounties looking for teen boy ‘unlawfully at large’ from Riverview psychiatric hospital

Nolan Godron left the hospital, located at 2721 Lougheed Highway in Coquitlam, without consent on Saturday

The Canadian border is pictured at the Peace Arch Canada/USA border crossing in Surrey, B.C. Friday, March 20, 2020. More than 4.6 million people have arrived in Canada since the border closed last March and fewer than one-quarter of them were ordered to quarantine while the rest were deemed “essential” and exempted from quarantining. THE CANADIAN PRESS/Jonathan Hayward
Majority of international travellers since March deemed ‘essential’, avoid quarantine

As of Oct. 20, 3.5 million travellers had been deemed essential, and another 1.1 million were considered non-essential

Most Read