How to get rid of toxic hammerhead worms
The invasive – and toxic – hammerhead worm has been spotted in Ontario.
Also known as a broadhead planarian, the worm can grow up to three feet (or a little more than 91 centimetres) long and has a neurotoxin, called tetrodotoxin, which is also found in pufferfish. The extremely potent poison can cause tingling or a rash when touched by humans, and nausea if swallowed.
But John Reynolds, a laboratory biologist and worm expert, said they’re not dangerous.
"They don't really do a lot of damage to crops or anything. They aren't fatal to people.”
Reynolds said the worm poses more of a threat to small animals and pets, but he doesn't know of any fatal cases.
“It's not going to kill them. But they can get upset, vomit or whatever, and they'll get a stinging sensation or numbing of their tongue," Reynolds explained. "I've heard rumours about pets, but I've never had any actual person, give me any useable data or information."
He added that the hammerhead worm doesn’t really have a predator.
"If you break a piece off or cut it, every piece that breaks off can become a new individual. So it's almost like they're here forever if you're not careful.”
A hammerhead flatworm is seen in this photo, spotted in Newmarket, Ont. on Sept. 23, 2021. (David Rudkin)
The worms have been spotted around Guelph and Hamilton over the past several years and reported to the invasive species platform iNaturalist.ca. The latest sighting was recorded in Newmarket in March.
"They're different than anything that's ever been here before. All of a sudden the change in the climate, things are moving up that you're finding here," Reynolds said.
He explained that the hammerhead worm originated in Southeast Asia and were likely brought over accidently through plant deliveries to nurseries.
"If they came up, not in bare root, but in ball and burlap, then it's quite conceivable that either small members of these flat worms or their cocoons were in the soil," he said.
Reynolds recommends gardeners purchase plants without any soil around their roots.
"When you go to the plant nursery, get bare root, because then you can really see, because the cocoons are quite small, they're really hard to see.”
If you do come across a hammerhead worm in your garden, Reynolds said the best thing to do is pick it up with gloves or a shovel and put it into a plastic bag, then leave the bag out in the sun until the worm dies. The bag and worm can be thrown into your garbage.
"Even if they were still slightly alive when in the garbage, they're going to a landfill, they're not going to bother anything in a landfill," he said.
According to Reynolds, the worms will likely move on from a garden if there isn’t any other insects or worms to eat.
"Their main focus is eating slugs, snails and my beloved earthworms,” he said. “If they can't find any of those, they're cannibalistic. They'll eat other members of their own species."
Composting concerns
Amanda Hunter, the owner of Worm Wrangler in Kitchener, provides red worms to customers who compost. While hammerhead worms are not an issue for those who do it indoors, Hunter said anyone using worms to help with outdoor composting could experience challenges.
"I would suspect that these hammerhead worms would potentially inhibit their ability to compost. They would probably decimate their worm population that they've invested to inoculate their compost with, that sort of thing," Hunter explained. "I'm not interested in seeing these guys flourish.”
Reporting sightings
Ontario’s Ministry of Natural Resources and Forestry encourages people to report sightings online through the Early Detection and Distribution Mapping System to assist in tracking the hammerhead worm.
The Invasive Species Centre also encourages people to report any hammerhead worms, or any other invasive species, on iNaturalist.ca.
CTVNews.ca Top Stories
DEVELOPING 122 active wildfires burning across Canada, 32 considered 'out of control'
The 2024 wildfire season has begun, and it's shaping up to follow last year's unprecedented destruction in kind, with thousands of square kilometres already consumed.
B.C. parents sentenced to 15 years for death of 6-year-old boy
A British Columbia Supreme Court judge has sentenced the mother and stepfather of a six-year-old boy who died from blunt-force trauma in 2018 to 15 years in prison.
Veteran TSN sportscaster Darren Dutchyshen has died
Veteran TSN broadcaster Darren 'Dutch' Dutchyshen, one of Canada’s best-known sports journalists, has died. He was 57. His family says 'he passed as he was surrounded by his closest loved ones.'
Miller scores late as Canucks grind out 3-2 win over Oilers in Game 5
J.T. Miller scored in the final minute of the game and the Vancouver Canucks came back for a 3-2 victory over the Edmonton Oilers in Game 5 of their second-round playoff series Thursday.
Think twice before sharing 'heartbreaking' social media posts, RCMP warn
Mounties in B.C. are urging people to think twice before sharing "heartbreaking posts" on social media.
Police issue Canada-wide warrant for Regina homicide suspect
Police have issued a Canada-wide warrant for a man wanted in a homicide which occurred in Regina on May 12.
Trudeau calls New Brunswick's Conservative government a 'disgrace' on women's rights
Prime Minister Justin Trudeau assailed New Brunswick's premier and other conservative leaders on Thursday, calling out the provincial government's position on abortion, LGBTQ youth and climate change.
Kevin Spacey receives star support as he fights to get his career back
Kevin Spacey is pushing back on the 'rush to judgment' against him and is being backed by some big names as he seeks to reclaim his acting career.
Speaker cuts ties with Sask. Party, alleges he faced threats, harassment from gov't MLAs
The Speaker of the Saskatchewan Legislature Randy Weekes has severed ties with the Sask. Party after accusing some members of harassment and intimidation tactics, including a situation he claimed saw the Government House Leader bring a hunting rifle to the legislative building.