First killer wasp nest discovered on US soil

Scientists in Washington state have discovered the first nest of so-called killer hornets in the United States and plan to destroy it on Saturday to protect native bees, authorities said.

Workers at the state Department of Agriculture spent weeks searching, trapping, and flossing to tie tracking devices to Asian giant hornets, which can cause painful stings to people and spit venom, but are the biggest threat to bees of which farmers depend to pollinate crops.

“Ladies and gentlemen, we did it,” agency spokeswoman Karla Salp said in a virtual briefing. Bad weather delayed Friday’s plans to destroy the nest found in Blaine, a city north of Seattle.

The nest is about the size of a basketball and contains roughly 100 to 200 hornets, according to the scientists, who have suspected it was in the area since invading insects started showing up late last year.

Authorities have said it is not known how they got to North America.

Despite their moniker and the hype that has raised fears in an already bleak year, the world’s largest hornets kill at most a few dozen people a year in Asian countries, and experts say that is likely far less.

Meanwhile, hornets, wasps and bees typically found in the United States kill an average of 62 people a year, the Centers for Disease Control and Prevention said.

The real threat from the Asian giant hornets, which are 5 cm long, is their devastating attacks on bees, which are already beset by problems like mites, disease, pesticides and food loss. A small group of hornets can kill an entire hive of bees in hours, and they have already destroyed six or seven hives in Washington state, authorities said.

The nest was found after a Department of Agriculture worker caught two hornets on Wednesday. Two more were captured Thursday, the agency said.

Using dental floss, “entomologists were able to connect radio trackers to three hornets, the second of which led to the discovery of the nest” on Thursday, agriculture officials said.

He was about 274 meters from the traps in a tree cavity on private property, authorities said.

Dozens of hornets were seen moving in and out of the tree about 2 meters above the ground. The owner is allowing the state to eradicate the nest and remove the tree.

Saturday’s plan is to fill the cavity with foam and cover it with plastic wrap to prevent the hornets from escaping, said Sven-Erik Spichiger, an entomologist with the Department of Agriculture.

Then, a tube will be inserted to suck up the trapped hornets and deposit them into a collection chamber, he said.

Workers will wear thick protective suits that can prevent hornets’ 6mm long stingers from hurting workers, Spichiger said.

They will also wear face shields because trapped hornets can spit painful venom into their eyes. “We extract them alive,” he said. “We will kill them.”

The tree will then be cut down to extract newborn hornets and find out if any queens have already left the hive, he said. Authorities suspect there may be more nests in the area and will continue to search.

“It is still a very small population and we are actively hunting them,” Spichiger said.

Scientists from the department have been searching for nests since the first Asian giant hornets were captured earlier this year.

The first confirmed detection of the hornet in the US was in December 2019 near Blaine and the first live hornet was caught in July. Just over 20 have been captured so far, all in Whatcom County.

The invasive insect is normally found in China, Japan, Thailand, South Korea, Vietnam, and other Asian countries.

The state of Washington and the Canadian province of British Columbia are the only places where hornets have been found on the continent.