An invasive species of worm dangerous to small animals, which could measure up to three feet long, is now well established in Ontario after crossing the American border.
“They are here. People are surprised to see them because they are so unusual. […] They don’t get very far alone. They must be transported. But they can spread quickly, because if you cut them, each piece becomes a new individual,” John Reynolds, a laboratory biologist and worm expert, told CTV News on Friday.
In recent months, the hammerhead flatworm or Bipalium adventitium has been seen several times in southern Ontario, particularly in the Newmarket, Hamilton and Kitchener regions, approximately 500 km from the border with Quebec. , according to the English-speaking media.
At least that’s what we can see on the website iNaturalist.ca, where citizens can list the presence of these critters with the date and images, to follow their expansion on the map, attributed to global warming.
This type of worm native to South Asia, which takes its name from the flat shape of its head, had already been observed sporadically in Quebec – including once in Mount Royal Park in 2018 – after having found their way in shipments of exotic plants, but in such small groups that the presence was negligible at the time, the expert estimated.
“They have become more visible recently,” insisted John Reynolds to the English-speaking media.
But according to the biologist, these worms, which can measure up to three feet long, release a neurotoxin deadly to small animals, called tetrodotoxin, which causes a reaction in humans upon contact with the skin.
“They can cause a terrible rash and make your hands tingle for a while. If you ingest one by mistake, it will just make you nauseous. It will certainly not be fatal,” he commented, advising to wear gloves when gardening.
The problem is that bipaliums are not easy to exterminate, since they multiply when they are cut in half and have no natural predators in Quebec, in addition to being resistant to the cold, we had previously reported. However, it is possible to immobilize them with a good dose of salt.
If you encounter one of these worms, you can report it to the Canadian site iNaturalist.ca to help track its spread, Emily Posteraro of the Invasive Species Center told CTV News.
“Ideally add precise location information, like an address. And take some photos, because that’s really the only way to verify detection,” she said.
