(Canadian Press)

(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.

Just Posted

Lightning in Kelowna, B.C. (Contributed)
Severe thunderstorm watch in effect for Okanagan

Conditions are favourable for the development of severe thunderstorms overnight

Justin Fotherby,17, and Ashley McMillan, 17 have been chosen for an invitation only competition that sees 20 of Canada’s top swimmers per event vying for a spot at the upcoming 2021 Tokyo Olympic Games. (Submitted)
Penticton swimmers off to Olympic trials

The pair are eyeing a spot on the Canadian team heading to the Tokyo Olympics

Bentley resting on a bench at Kal Park in Vernon not knowing there is a baby rattlesnake curled up below. Bentley jumped down and was bit by the snake. (Facebook)
Dog bit by baby rattler at popular Vernon park

The rattlesnake was hidden underneath a park bench when it struck out

Renderings of what the skating rink could look like beside City Hall between Martin and Main in downtown Penticton. (Activate Penticton image)
Outdoor skating rink back at Penticton council

City staff recommend going forward with rink which could host 2022 BCHL’s 60th year celebration

Longtime SOWINS volunteer Diane Fru (far left) walks with members of her family as they Walk To End Abuse Sunday, June 13, 2021. South Okanagan Women In Needs Society (SOWINS) raised a record amount this year. (Monique Tamminga Western News)
Walk to End Abuse in South Okanagan breaks fundraising record

More than $53,000 raised so far while the pandemic has increased need for SOWINS’ services

Canadian Prime Minister Justin Trudeau participates in a plenary session at the G7 Summit in Carbis Bay, England on Friday June 11, 2021. THE CANADIAN PRESS/Adrian Wyld
Canada donating 13M surplus COVID-19 vaccine doses to poor countries

Trudeau says the government will pay for 87 million shots to be distributed to poor countries

Premier John Horgan speaks as provincial health officer Dr. Bonnie Henry, right, and health minister Adrian Dix look on during a press conference to update on the province’s fall pandemic preparedness plan during a press conference from the press theatre at Legislature in Victoria, Wednesday, Sept. 9, 2020. THE CANADIAN PRESS/Chad Hipolito
B.C. officials to provide details on Step 2 of COVID reopening plan Monday

Step 2 could allow for larger gatherings and a resumption of recreational travel

Indigenous Services Minister Marc Miller is seen during a news conference, Wednesday May 19, 2021 in Ottawa. THE CANADIAN PRESS/Adrian Wyld
Indigenous child-welfare battle heads to court despite calls for Ottawa to drop cases

Feds are poised to argue against two Canadian Human Rights Tribunal rulings

Two-year-old Ivy McLeod laughs while playing with Lucky the puppy outside their Chilliwack home on Thursday, June 10, 2021. (Jenna Hauck/ Chilliwack Progress)
VIDEO: B.C. family finds ‘perfect’ puppy with limb difference for 2-year-old Ivy

Ivy has special bond with Lucky the puppy who was also born with limb difference

A million-dollar ticket was sold to an individual in Vernon from the Lotto Max draw Friday, June 11, 2021. (Photo courtesy of BCLC)
Lottery ticket worth $1 million sold in Vernon

One lucky individual holds one of 20 tickets worth $1 million from Friday’s Lotto Max draw

A logging truck carries its load down the Elaho Valley near in Squamish, B.C. in this file photo. THE CANADIAN PRESS/Chuck Stoody
Squamish Nation calls for old-growth logging moratorium in its territory

The nation says 44% of old-growth forests in its 6,900-square kilometre territory are protected while the rest remain at risk

Flowers and cards are left at a makeshift memorial at a monument outside the former Kamloops Indian Residential School to honour the 215 children whose remains are believed to have been discovered buried near the city in Kamloops, B.C., on Monday, May 31, 2021. THE CANADIAN PRESS/Darryl Dyck
‘Pick a Sunday:’ Indigenous leaders ask Catholics to stay home, push for apology

Indigenous leaders are calling on Catholics to stand in solidarity with residential school survivors by not attending church services

(Heather Lueck image)
Crash north of Enderby knocks out power, slows Highway 97A traffic

A witness captured footage of a medical helicopter landing at the scene

Most Read