British Columbia and Washington State are joining forces for a cross-border effort to find and eradicate Asian giant hornet nests this summer.
Sometimes called murder hornets, the insects are an invasive species native to East and South Asia that threaten to destroy honey bee colonies, which are important for BC and Washington’s agriculture industries.
Both jurisdictions are laying out traps for the Asian giant hornets to detect where they’re living and lead investigators back to their nests to destroy them.
Officials are asking “citizen scientists” on both sides of the border to lay out their own simple pop bottle-style traps and contact the appropriate agency in BC or Washington if they spot an unusually large hornet.
“We would like to use the public’s eyes to report sightings because we don’t have enough resources to be everywhere all the time,” Sven-Erik Spichiger, managing entomologist with the Washington State Department of Agriculture, said at a Wednesday news conference.
Officials suggest using a mixture of water and brown sugar to attract the insects, but orange juice, grape juice, and rice wine will also work.
After being spotted for the first time in BC in 2019 and several more times on both sides of the border last summer, scientists and agricultural officials say the pressure is on to eradicate the invasive insect before it establishes itself in the Pacific Northwest.
The hornets are known to attack honey bees, and will slaughter entire colonies in a matter of hours by decapitating the bees. Then, they’ll take over the bee colony as their own and eat the young.
They threaten to cause untold damage to the Pacific Northwest’s beekeeping industry, which will in turn make it more difficult to grow certain types of produce the Lower Mainland is known for, such as blueberries.
The hornets nest in the ground and will aggressively defend their home if disturbed.
Paul van Westendorp, BC’s provincial apiculturist, recounted how a nest was found in Nanaimo in 2019 that was next to a public park and walkway. If a dog or child had sniffed the nest, they could have been attacked.
“If there’s direct exposure to you of a hornet’s nest, absolutely there is danger to your health and well-being.”
He added the hornets are an apex predator, and they will kill other native species of wasps and hornets. Eliminating those middle predators could upset the insect ecosystem, leading to more types of unwanted bugs here.
Officials believe the hornets were introduced via marine traffic coming into one of BC or Washington’s ports. They suspect a young queen could have insulated herself in a shipping container or vehicle and emerged here in the spring to set up a new nest.
They added more invasive species could be introduced this way in the future.
Van Westendorp believes the Fraser Valley is the most attractive ecosystem for the Asian giant hornets, and doesn’t think they’ll establish themselves in BC’s evergreen forests or further east in the Interior.
That’s why he’s particularly focused on asking BC beekeepers to monitor for the hornets.
With consistent “predation” from humans in the form of trapping and extermination, van Westendorp hopes Asian giant hornets can be brought under control this year.
Last year in BC there were six confirmed sightings of Asian giant hornets.
South of the border, Washington state reported 31 confirmed sightings, plus at least 500 insects found at a nest that was destroyed.
Spichiger shared a map of the traps planted for this summer, where the focus is near previous sightings in places such as Whatcom, Skagit, San Juan, Island, Jefferson and Clallam counties Birch Bay, Custer, and Blaine.
He believes putting out a trap is in people’s best interest, because it’s safer to know in advance if there are Asian giant hornets in your area rather than unwittingly disturbing a nest.
“This is not a species that we want to tolerate here in the US and certainly not in Washington State,” Spichiger said.
Those interested in setting up traps should put them out by July.