A crew from the Washington State’s Department of Agriculture (WSDA) has eradicated the first nest of Asian giant hornets ever found in the United States, the Associated Press (AP) reports. Donning thick, white protective suits that made them look more like astronauts than entomologists, the team vacuumed 85 giant hornets from the nest, which was located inside a tree trunk on Saturday, October 24, according to a statement. WSDA entomologist Chris Looney captured an additional 13 other hornets using a net on Friday, according to an online press conference held this afternoon.
The suits may look like overkill, but they’re supposed to protect the wearer from the hornet’s 6-millimeter-long stinger, which can pierce ordinary bee-keeping suits and delivers a painful sting that some have likened to having a hot nail driven into one’s flesh. The suits also feature face shields that are aimed at blocking the venom that the world’s largest hornet—queens can reach two inches long—is capable of spraying into the eyes of any creature that threatens them or their hive, per the AP.
The massive invasive insects, first introduced to the American public as “murder hornets” back in May, hail from Asia and are known for attacking and devouring entire hives of honeybees in a matter of hours. Their arrival in the Pacific Northwest in late 2019 led many to worry that a full-scale biological invasion could be in the works, which could threaten the nation’s buzzing pollinators—which are already under threat and whose contributions to U.S. food production is valued at some $15 billion.
WSDA entomologists found the nest near the Canadian border in the city of Blaine, Washington, after weeks of trying to capture individual hornets with traps set in the surrounding area. Once the WSDA had trapped some hornets in the area, workers attached tiny tracking devices to the insects with dental floss and eventually tracked them back to the hive, BBC News Reports.
“The eradication went very smoothly, even though our original plan had to be adapted due to the fact that the nest was in a tree, rather than the ground,” says WSDA entomologist Sven Spichiger in the statement. “While this is certainly a morale boost, this is only the start of our work to hopefully prevent the Asian giant hornet from gaining a foothold in the Pacific Northwest. We suspect there may be more nests in Whatcom County.”
First located last Thursday at 4 p.m. local time, the WSDA team approached the nest around 5:30 a.m. on a cold Saturday morning, per the statement. During a press briefing this afternoon Spichiger said, the air was about 30 degrees Fahrenheit, which meant the hive was quiet, with only a few workers emerging.
To get more of the giant hornets to exit the hive, the team thwacked the tree with a wooden board to disturb the insects. Team members sucked up the flurry of mad hornets flying out of the tree-hollow using a vacuum.
After things died down, the team took extra steps to make sure the nest had been destroyed. They filled the tree hollow the hornets were inhabiting with spray insulation foam, wrapped the tree up with cellophane, pumped carbon dioxide gas inside the tree to put any remaining hornets to sleep and set baited traps in the area to catch any stragglers returning to the hive.
Next, a contractor hired by the WSDA will cut down the tree, allowing entomologists to examine the size of the nest and determine whether the colony had started producing new queens, which typically set off on their own to start new hives around this time of year. Technicians with the agency will continue to set traps in Washington State through November in hopes of locating additional nests. In the press briefing, Spichiger indicated that he thinks there could be three other nests in Whatcom County, based on the distribution of Asian giant hornet specimens his agency has collected.