Washington State Department of Agriculture (WSDA) announced Saturday that a team of heavily suited-up entomologists armed with industrial-strength vacuums successfully eradicated an Asian giant hornet nest two days after finding the nest in a tree on private property in Blaine, Wash.
In all, the entomologists with WSDA’s Pest Program removed 98 worker hornets. During the early morning extraction, 85 hornets were vacuumed out of the nest and another 13 live hornets were collected with a net while observing the nest on Friday.
“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,” managing entomologist Sven Spichiger said. “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.”
At about 5:30 a.m. Saturday, the team started by putting on protective suits and setting up scaffolding around the tree.
“The team stuffed dense foam padding into a crevice above and below the nest entrance and wrapped the tree with cellophane, leaving just a single opening. This is where the team inserted a vacuum hose to remove the hornets from the nest,” according to a WSDA news release.
The work was slow at first, but a few hard whacks to the tree with a wooden board dislodged the so-called “murder hornets,” when they began coming out of the tree and into the vacuum canister. Remaining hornets were stunned with carbon dioxide pumped into the tree.
The tree was then sealed with spray foam and wrapped in cellophane. Traps were placed nearby to catch stragglers.
“This weekend’s successful operation is due in large part to the careful planning and hard work of our Pest Program team,” WSDA Director Derek Sandison said. “I also want to thank the landowners, all those who have reported Asian giant hornet sightings to us and the citizen scientists who set traps, as well as staff with the U.S. Department of Agriculture, Washington State University and the University of Washington who have assisted in these efforts.”
In the coming week, the WSDA Pest Program intends to cut the tree down and open it to see how big the nest was. The entomologists also want to determine whether the nest had begun to produce new queens or not.
“We congratulate the Washington State Department of Agriculture for eradicating this nest,” said Osama El-Lissy, Deputy Administrator of the U.S. Department of Agriculture’s Plant Protection and Quarantine program. “Thanks to their expertise and innovation, this nest is no longer a threat to honey bees in the area. We are also pleased that the radio tags we provided worked so well, allowing state entomologists to tag and track a live Asian giant hornet back to the nest. It’s a strong example of our close cooperation in combatting this pest.”
WSDA will continue setting traps through at least November in hopes of catching any more Asian giant hornets still in Whatcom County and potentially locating any other active nests.
Asian giant hornets, an invasive pest not native to the U.S., are the world’s largest hornet and a predator of honey bees and other insects. A small group of Asian giant hornets can kill an entire honey bee hive in a matter of hours. Go to agr.wa.gov/hornets to learn more about Asian giant hornets and the state’s trapping and eradication project.