(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.

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

Just Posted

Toronto Public Health nurse Lalaine Agarin makes preparations at Toronto’s mass vaccination clinic, Jan. 17, 2021. THE CANADIAN PRESS/Frank Gunn
3 deaths, 234 new cases of COVID-19 in Interior Health over the weekend

One death connected to outbreak at Kamloops’ Royal Inland Hospital, where 20 patients and 28 staff have tested positive

(THE NEWS – files)
Snowy days ahead for the Okanagan and Shuswap

The region could get up to 5 cm by Thursday

People skate on a lake in a city park in Montreal, Sunday, January 10, 2021. THE CANADIAN PRESS/Graham Hughes
The end of hugs: How COVID-19 has changed daily life a year after Canada’s 1st case

Today marks the one year anniversary of COVID-19 landing in Canada

The Okanagan Regional Library is holding a pair of online contests for its young readers. (File photo)
Okanagan Regional Library challenges young readers

Pair of contests online aimed at kids aged up to 18

Terrance Josephson of the Princeton Posse, at left, and Tyson Conroy of the Summerland Steam clash during a Junior B hockey game at the Summerland Arena in the early spring of 2020. (John Arendt - Summerland Review)
QUIZ: How much do you know about hockey?

Test your knowledge of Canada’s national winter sport

Crews with Discovery Channel film as an Aggressive Towing driver moves a Grumman S2F Tracker aircraft around a 90-degree turn from its compound and onto the road on Saturday, Jan. 23, 2021. It was the “most difficult” part of the move for the airplane, one organizer said. (Jenna Hauck/ Chilliwack Progress)
VIDEO: Vintage military plane gets towed from Chilliwack to Greater Victoria

Grumman CP-121 Tracker’s eventual home the British Columbia Aviation Museum on Vancouver Island

ICBC has seen savings on crash and injury claims in the COVID-19 pandemic, with traffic on B.C. roads reduced. (Penticton Western News)
ICBC opens online calculator for rate savings starting in May

Bypassing courts expected to save 20% on average

Salmon Arm RCMP search a property in the 700 block of Grandview Bench Road in March 2019, assisting Edmonton police with an investigation that led to the arrest of a Salmon Arm man man who was charged in relation to an Edmonton bank robbery and a related explosions. (File photo)
Salmon Arm man accused in Edmonton bank explosions in court for weapon offences

Local provincial court appearances for charges including possessing weapon for dangerous purpose

Salmon Arm’s Halle Krawczyk gives a thumbs up following surgery on Jan. 22 in Pittsburgh, her second of three battling an extremely rare form of cancer that formed tumours on her two upper vertebrae and the clivus behind the nose. (Contributed)
‘Absolutely perfect:’ Salmon Arm girl’s surgeries for rare cancer exceed expectations

Halle Krawczyk doing well, mom credits hundreds of people praying for making the difference

(AP Photo/Elaine Thompson, File)
16% boom predicted for B.C. real estate sales in 2021: experts

Along with sales, the average price of homes is also predicted to rise, by nearly 8 percent

Zaudanawng “Jay-Dan” Maran in his Creston home. Hanging on the wall behind him is a logo of Kachin’s Manaw festival. Photo: Aaron Hemens
From Myanmar to Creston: The story of a refugee

In October 2007, Zaudanawng “Jay-Dan” Maran and his friends encountered a woman being sexually assaulted by two Myanmar soldiers.

Karen Hudema, 71, admitted she felt left out due to her hearing loss, but now, after being awarded free hearing devices through the National Campain for Better Hearing Program from HearingLife Canada, she says her self-esteem has been restored. (Caitlin Clow - Vernon Morning Star)
‘I have my self-esteem back’: Vernon senior awarded hearing aids

Free testing leads to life-changing improvement for local lady

FILE – Canadian Prime Minister Justin Trudeau delivers his opening remarks at a news conference outside Rideau cottage in Ottawa, Tuesday, January 19, 2021. THE CANADIAN PRESS/Adrian Wyld
Vaccine CEO ‘very, very clear’ that Canada’s contracts will be honoured: Trudeau

Trudeau says he spoke to Moderna CEO on the morning of Jan. 26

The trial of Harry Richardson began Monday at the Nelson courthouse. File photo
Trial of man accused of shooting RCMP officer in West Kootenay in 2019 begins

Harry Richardson is facing five charges in a Nelson courtroom

Most Read