If you feel like your house, your yard – even your whole town is being overrun with caterpillars this year, you’re not alone.
Many parts of the country are seeing explosions in the fuzzy, striped critters known as forest tent caterpillars.
Why are the creepy crawlies suddenly everywhere, and are these infestations another sign of climate change?
Relax, says Amanda Roe, a research scientist with the Canadian Forest Service; this is all perfectly normal.
Roe told CTV’s Your Morning that forest tent caterpillars are native to Canada and go through cycles in which there are several years of low numbers of the critters, followed by years of high densities.
“Why they do that, we aren’t exactly sure, but we know they go in very regular cycles,” she said from Sault Ste. Marie, Ont. “We just happen to be in the high number period right now.”
While many of us are just noticing the caterpillars now, they have actually been growing for many weeks, high up in the trees, she said. They have been nibbling on a buffet of tree leaves, often stripping a tree bare as they fatten up. When that happens, they need to leave a tree to migrate to another, lusher one.
“This is when people really start to notice them because they are big and they are on the ground, or on their cars, or on their decks,” Roe said.
While finding hundreds of caterpillars on your deck or yard can be a bit unsettling, Roe says once the insects start migrating, it’s a sign they’re actually at the end of their caterpillar life.
Many have already begun to pupate and form cocoons on the sides of buildings, fences or trees. After 10 days, they will emerge as rather dull brown moths, living only for another night or two.
“(The moths) actually don’t even have mouths; they can’t eat. They have one job: make babies,” Roe said
After the moths’ eggs are laid, new baby caterpillars won’t emerge again until next spring, says Andrew Hebda, a curator of zoology with the Nova Scotia Museum of Natural History. “There's only one generation per year, so they'll come in, they'll be feeding on those fresh leaves, they'll go through those transformations into adults, and then, as adults, they'll go and lay their eggs for next year's crop,” Hebda told CTV Atlantic last week.
While a caterpillar-ravaged tree might not be a pretty sight, Roe said the insects don’t actually damage the trees they nibble on.
“The really neat thing about our trees is that they have adapted to this species, because it is native. They have the time to put out a whole new flush of leaves,” Roe said.
