Brown marmorated stink bugs in Metro Vancouver raise concerns

Stink bugs are a nuisance to those dealing with the critters, but it turns out some types of them aren’t just an annoyance in Metro Vancouver.

The brown marmorated stink bug is an invasive species. You may have noticed more of them in recent weeks around the Lower Mainland, likely due to the weather the region has been experiencing.

“This year has been a very odd year. They like warm and dry, and we’ve had an extremely warm and dry season, that could be the link,” Gail Wallin, executive director, Invasive Species Council of BC, explained.

“They’re actually a major pest to many of our food industries — they attack more than 100 different plants, at least. And when something’s not from the local area, its populations can really explode because they don’t have their normal predators with us, and that’s what’s happening with the brown marmorated stink bug.”

The Invasive Species Council of BC is asking people to keep an eye out for brown marmorated stink bugs, which are not native to the province. (Courtesy Invasive Species Council of BC)

The brown marmorated stink bug first came to North America from Asia in the early 2000s, though it’s hard to determine exactly how they got here. They started popping up around 2016 in the Lower Mainland, with Wallin saying the population then started to “explode.”

They tend to enjoy fruit crops, of which there are plenty around the region.

Wallin says while there are some factors that are slightly helping keep stink bug numbers in check, the Lower Mainland has a “rich population” of the critters, meaning people need to be alert to keep them from spreading to new locations.

“The general rule of thumb is we don’t want to bring new invasive species into any part of the province or country and that’s because when you get a new invasive species, like the brown marmorated stink bug, it’s actually going to be competing with native species or changing the habitat for the native species that are there. And an ecosystem is actually very delicately balanced,” she told CityNews.

Keep brown marmorated stink bugs from spreading, says Invasive Species Council of BC

Locals have a role to play, Wallin notes. She says the underlying message is: restrict where they are.

“Prevention is by far the best thing to do. Making sure that we don’t take this brown marmorated stink bug to a new location, like the interior, the Kelowna area, other fruit areas — let’s restrict its population as much as we can,” Wallin said.

She recommends people check their homes, adding stink bugs will be looking for warm spots over the winter months.

“They’re actually very distinct, they’ve got that really brown, shield look. They look like some of our native stink bugs, so you have to look closely to see if it’s got white strips on its antenna — so there’s ways to distinguish it.”

While it may not be appealing to get up close with a stink bug, Wallin says it’s important to do these checks. The Invasive Species Council is encouraging people to report what they see to the group any time, including if you think you’ve spotted a brown marmorated stink bug, and to leave any bugs where they found them — not to move them around.