Menace in disguise: Biting Asian ladybug giving helpful cousin a bad name
A leading bug expert in Winnipeg says a stinky, biting cousin of the ladybug is on the rise in the area, where it’s masquerading as its more docile relative.
The Asian ladybug (a.k.a ladybird or ladybeetle) was first introduced in North America to kill aphids, but its numbers have surged to the point where it’s becoming a problem in some parts of the country. The pest varies in colour but can look a lot like the North American ladybug, except it has more black spots on its back, and it can be red, yellow or orange in colour.
Entomologist Taz Stuart says these invaders are not nearly as friendly as their local cousins. They bite, they create a stinky smell and they like to shack up in people’s homes for the winter, whether they’re invited or not.
“They look like a ladybug and at this time of year they’re coming in from the fields and the crops because they’re getting cut down,” Stuart told CTV Winnipeg.
Health Canada says North American ladybugs are “among our most beneficial insects,” because they eat all kinds of pests, including aphids. The Asian ladybugs also eat aphids, but their swarming and biting habits make them much more of a pain.
Stuart says the Asian ladybeetle can be found in cracks, crevices, window sills and doorframes around the home during colder months, and can cause a stinky smell when they die in numbers.
Some Winnipeg residents say they’ve had some unpleasant encounters with the bugs while enjoying the outdoors.
“I was just walking along the path and I felt a pinprick kind of feeling here, and I just saw the ladybug and it shooted off,” Byron Hildebrand told CTV Winnipeg.
Jessica Nikkel says she was surprised to suffer an Asian ladybeetle bite while taking her dog for a walk. “I thought it was a fly and I looked and sure enough it was a ladybug,” she said.
Health Canada says there are no approved pesticides for dealing with the Asian ladybeetle. Instead, it recommends sealing up cracks and crevices for the winter.
“Once ladybugs have moved in, there are few treatment options,” Health Canada says. “Sweep or vacuum them up, then seal and throw out the bag so they can’t escape back into your home.”
Asian ladybeetles have spread throughout North America, but Stuart says the bugs haven’t been much of a problem in Winnipeg until recently.
“Previous to 2016 you really hadn’t seen a whole bunch of Asian ladybird beetles out there, but last year we had an increase,” he said. “We had a good number of calls around Halloween and people were concerned.”
With files from CTV Winnipeg