(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

Two volunteers work to sieve a sample of sand and ocean water through a filter, capturing any potential microplastics. (Courtesy of Ocean Diagnostics)
Victoria startup making waves in microplastics research

New products from Ocean Diagnostics will make research faster, more affordable

Willows Beach in Oak Bay. (Black Press Media file photo)
Seven days of sun set to shine on Greater Victoria

Special weather statement warns of higher than usual temperatures

Chef Trevor Randle leads a June 21 online cooking featuring recipes – beef zesty lettuce wraps, blueberry strudel and blueberry spritzer. (Courtesy We Heart Local BC)
Free online cooking course explores B.C. blueberries and beef

Chef Trevor Randle calls them the province’s most flavourful foods

Island Savings kick-starts the Equipped to Heal campaign with $120,000. (Courtesy Victoria Hospitals Foundation)
Latest Victoria Hospitals Foundation campaign targets $1M for mental health

Goal is to outfit new 19-bed unit at Eric Martin Pavilion

Shaelyn Sinnott of Oak Bay Volunteer Services delivers groceries for client Irene Kenny. The organization has kept up delivery of food and medication throughout all phases of the COVID-19 pandemic. (Courtesy Oak Bay Volunteer Services)
Oak Bay volunteers keep critical services running

Duo drove between Oak Bay and Jubilee three days a week, twice a day during pandemic

Jesse Roper tackles weeds in his garden to kick off the 2021 season of What’s In My Garden Man? (YouTube/Whats In My Garden)
VIDEO: Metchosin singer-songwriter Jesse Roper invites gardeners into his plot

What’s In My Garden, Man? kicks off with the poop on compost

FILE – Most lanes remain closed at the Peace Arch border crossing into the U.S. from Canada, where the shared border has been closed for nonessential travel in an effort to prevent the spread of the coronavirus, Thursday, May 7, 2020, in Blaine, Wash. The restrictions at the border took effect March 21, while allowing trade and other travel deemed essential to continue. (AP Photo/Elaine Thompson)
Feds to issue update on border measures for fully vaccinated Canadians, permanent residents

Border with U.S. to remain closed to most until at least July 21

A portion of the George Road wildfire burns near Lytton, B.C. in this Friday, June 18, 2021 handout photo. THE CANADIAN PRESS/HO, BC Wildfire Service *MANDATORY CREDIT*
Blaze near Lytton spread across steep terrain, says BC Wildfire Service

Fire began Wednesday and is suspected to be human-caused, but remains under investigation

Blair Lebsack, owner of RGE RD restaurant, poses for a portrait in the dining room, in Edmonton, Friday, June 18, 2021. Canadian restaurants are having to find ways to deal with the rising cost of food. THE CANADIAN PRESS/Jason Franson
Canadian restaurateurs grapple with rising food costs, menu prices expected to rise

Restaurants are a low margin industry, so there’s not a lot of room to work in additional costs

RCMP crest. (Black Press Media files)
Fort St. John man arrested after allegedly inviting sexual touching from children

Two children reported the incident to a trusted adult right away

A Lotto 6/49 ticket purchased in Parksville for the June 19, 2021 draw is a $3M winner. (Submitted photo)
Winning Lotto 6/49 ticket worth $3M purchased on Vancouver Island

Lottery prize winners have 52 weeks to claim jackpot

Barbara Violo, pharmacist and owner of The Junction Chemist Pharmacy, draws up a dose behind vials of both Pfizer-BioNTech and Oxford-AstraZeneca COVID-19 vaccines on the counter, in Toronto, Friday, June 18, 2021. An independent vaccine tracker website founded by a University of Saskatchewan student says just over 20 per cent of eligible Canadians — those 12 years old and above — are now fully vaccinated. THE CANADIAN PRESS/Nathan Denette
At least 20% of eligible Canadians fully vaccinated, 75% with one dose: data

Earlier projections for reopening at this milestone didn’t include Delta variant

This undated file photo provided by Ernie Carswell & Partners shows the home featured in the opening and closing scenes of The Brady Bunch in Los Angeles. Do you know the occupation of Mike Brady, the father in this show about a blended family? (Anthony Barcelo/Ernie Carswell & Partners via AP, File)
QUIZ: A celebration of dad on Father’s Day

How much do you know about famous fathers?

Most Read