epa07787998 Two experts prepare an explosive device to detonate an Asian hornet nest during a campaign to eradicate the invasive species in Pravia, Asturias, northern Spain, 23 August 2019. The Asian hornet (Vespa velutina) arrived in Spain in 2010 and Asturias' regional authorities launched a pioneering project with the use of explosive to eradicate the plague. The insect poblation is growing due to the environment conductive, enough food and the lack of predators. EPA-EFE/J.L.Cereijido
The so-called stinging "murder hornets," the world's largest hornets, can grow to two inches (5 cm) in length and prey on native bee and wasp populations, consuming honeybee hives and threatening agriculture.
The hornets are not native to North America. They were first detected in the United States in 2019, when a hornet was reported in Washington's Whatcom County, near the Canadian border, according to the WSDA.
This latest nest was uncovered in the base of a dead alder tree in Whatcom County and was eradicated on Wednesday.
"They did actually attempt to sting us this time," said Sven Spichiger, the department's managing entomologist, during a virtual news conference on Thursday.
"We are all very happy to say that our hornet suits worked very well and no injuries were sustained. We responded to this by blocking off the second entrance, which stopped them from coming out," he said.
In addition to the 113 worker hornets vacuumed out, staff netted another 67 other hornets in the area. The nest itself had nearly 1,500 hornets in various stages of development, the WSDA said in a statement.
Some of the live hornets were sent to USDA for research. The other will be destroyed, the agency said.
WSDA said it will continue to trap for Asian giant hornets through the end of November.
Once spotted and captured, hornets are fitted with a radio transmitter and released in the hope they can be followed back to the nest.
After a nest is confirmed to be in a tree by thermal imaging, the tree is wrapped in plastic while its trunk is hit with a piece of wood to get the hornets out so they can be vacuumed up and eradicated.