Tent caterpillars crawling all over Edmundston
Scientist says an individual female can produce anywhere from 150 to 400 eggs
They're on the trees.
They're on the roads.
They're on homes and businesses.
They are tent caterpillars and hoards of them have descended on Edmundston.
"Two days ago, there were only a few. Then I sprayed it yesterday. It helps a little, but not enough," said Gilles Levesque in French.
The Edmundston resident has been fighting back against the crawlers by spraying his house with a mixture of dish soap and vinegar.
"We wonder what we can do about this. It increases from year to year," said Ronald Laplante, another resident in town.
"Last year, we were not infested in the same way."
Rob Johns with Natural Resources Canada's Atlantic Forestry Centre said the species is called the forest tent caterpillar.
"At this time of year they leave the [nest] and just start roaming pretty much randomly in different directions trying to find a place where they can spin a cocoon," Johns said.
But why are there so many of them?
Johns said it's because an individual female can produce anywhere from 150 to 400 eggs.
"You can imagine it wouldn't take long for a very small population to explode."
The species also has dramatic, decade-long cycles.
"They are well known to outbreak basically every 10 years. We're on a 10-year schedule right now, so basically right on time," he said, adding that usually the population is controlled by predators or disease outside of peak years.
"But every once in a while there's just a slight release, where the insects are able to get a little bit ahead of these predators, and it doesn't take very much for them to explode into these large-scale outbreaks. "
Johns said this has been going on for hundreds of years, with records of these 10-year cycles dating back to the 1700s.
Their preferred food is the aspen tree, and they like to feed in groups, so you won't usually find them too far apart from each other, Johns said.
But if people are worried about damage to trees, it's already too late.
"They're done eating [ and] they're basically just looking for a place to spend the winter. So any of the damage that they were going to cause has been caused already."
But there's no danger to people, he said.
"It's really more of an esthetic issue for people. They don't want to see these big mats of caterpillars," Johns said.
"The densities will be high for this year and maybe another year or two, then they will collapse and we won't see them for another 10 years or so."
City tries to control what it can
In Edmundston, the caterpillars are also swarming in municipal parks.
But fear not, said Daniel Gautreau, the city's green spaces and environment co-ordinator.
"It's not really dangerous for our trees," Gautreau said in French.
But the city is still working to keep the caterpillars under control, with workers cleaning picnic tables and park benches, he said.
"But it has to be started again every morning."
Gautreau said the good news is that it won't last for long.
"Two, three weeks," he said.
"We're at the start of the second week, so it could last another week. Maybe another two weeks."
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With files from Radio-Canada and Rachel Cave