If you’ve spotted a few too many little orange insects crawling around your windowsills lately, you’re definitely not alone.
Over the past few days, the people of Montreal have been taking to Reddit to ask the same question: why are there suddenly so many ladybugs everywhere?
Some say they’ve found them clustered on windows and walls, while others say they keep turning up inside their apartments.
As it turns out, there’s a pretty simple explanation. And the bugs you’re seeing might not be ladybugs at all.
They’re probably Asian lady beetles
Most of the “ladybugs” invading homes this time of year are actually Asian lady beetles, an introduced species that looks a lot like the native ones.
The easiest way to tell them apart is by the M-shaped marking behind the head, along with two white spots nearby. Asian lady beetles are also generally bigger than Quebec’s native ladybugs, and their colour can range from yellow and orange to red or even black, with anywhere from zero to nearly 20 spots.
Montreal’s Insectarium says the most common form in Canada is orange with 19 black spots.
The species is native to East Asia and was introduced to the United States in the 1980s to help control aphids. It made its way to Quebec in the early 1990s and has since spread across the southern part of the province.
Why they’re showing up now
There’s a reason your home suddenly feels like an insect hotel.
According to the Insectarium, Asian lady beetles gather in October and look for a place to spend the winter. Unlike some insects, they’ve adapted to Quebec’s cold by taking shelter in protected spots, and our homes happen to be one of them.
CAA-Quebec says they gather by the thousands on the sun-exposed sides of houses, searching for warmth. From there, they make their way in through cracks, windows and other openings. Come spring, they’ll do the reverse, trying to get back outside to start their life cycle again.
Are they dangerous?
Not really, but they can be a bit of a nuisance.
The Insectarium says insects like these pose no danger to homes or humans. Asian lady beetles don’t sting, transmit disease or contaminate food, though they might give you a slight nip if you handle them.
The real annoyance comes when they’re disturbed. When crushed or threatened, they release a foul-smelling orange liquid that can leave yellow stains on some surfaces. So whatever you do, try not to squish them.
If you have pets, CAA-Quebec says the beetles generally aren’t toxic to cats or dogs. But eating a lot of them could cause some digestive irritation, so it’s worth calling your vet if your pet shows any unusual symptoms.
And to be fair to them, they’re not all bad. Asian lady beetles help control aphids that damage plants. But they also compete with native lady beetles, which is why they appear on Quebec’s list of exotic species of concern.
How to keep them out
The best defence is stopping them before they get inside. Here’s what experts recommend:
- Caulk holes, cracks and gaps, especially on the sunny sides of your home
- Keep window and door screens in good shape, and don’t take them down until November
- Add covers or screens to exterior ducts and vents
- Check that your door frames are properly sealed
- Clear away debris around your home that could give them a place to hide
How to get rid of them
If a few have already made themselves at home, the Insectarium says a vacuum is your best bet. Just make sure to empty it or throw out the bag right away so they can’t crawl back out.
CAA-Quebec says strong scents like peppermint, citronella, camphor, garlic or cayenne pepper are sometimes used to keep them away, but results vary and the effect usually doesn’t last.
Using pesticides outside isn’t recommended either, as their decomposing bodies can end up attracting other insects looking for food.
If things get really out of hand, a pest control specialist may be able to help.
So the next time you see a swarm of little orange beetles on your window, you’ll know exactly who your uninvited guests are, and how to send them packing.
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