Scientists ready for another AGH trapping season

Washington State Department of Agriculture (WSDA) officials are preparing to start Asian giant hornet monitoring efforts this year with a new monitoring program of paper wasp nests and setting 1,000 traps in Whatcom County.

WSDA is asking Washington residents to “adopt” one or more paper wasp nests to monitor from June through the end of October. The new program comes after scientists noticed a pattern of the invasive hornets attacking larvae in paper wasp nests. Participants will get a site ID number to log weekly check-ins after registering their paper wasp nest in WSDA’s online registration form. The nest should be monitored at least five minutes per week. More information on the new program can be found at bit.ly/3MK5OcZ.

“In 2021, all three of our nests came from public reports where folks had noticed Asian giant hornets feeding on the paper wasps in these paper wasp nests,” WSDA managing entomologist Sven Spichiger said during a May 24 press conference. “This turned out to be a very valuable tool for us and it’s pretty easy to do.”

The state agency caught 14 hornets last year, the first of which was a dead hornet found in Snohomish County. WSDA officials said they will not put additional monitoring efforts since no other hornets were detected. All three hornet nests eradicated last year were within 2 square miles of each other near the U.S./Canada border in east Blaine.

“We’re still in a very tight and confined area which leads us to a bit of optimism that it has not spread to multiple counties and does not appear to be throughout the rest of Whatcom County, which is really good news,” Spichiger said.

Spichiger said the state agency had a “fairly serious” unconfirmed report during the weekend of May 20 that scientists are investigating. The hornet was found in the same area where all three nests were eradicated last year.

“We’re not sure what to make of it because it’s very early for the type of activity that was described,” he said, later adding, “We have no verified detections yet in 2022, but as always, we’ll let everybody know if we do.”

He added that many of the state’s insect trapping programs are running late because of cool spring weather. The insects aren’t appearing as early. WSDA spokesperson Karla Salp later said scientists have added traps around the unconfirmed sighting as a precaution.

WSDA workers will add about 1,000 traps near the U.S./Canada border, from Lynden to the coast. They will also finish their last year of trapping in Bellingham near where a hornet was killed in 2020. Scientists have to trap in an area for three consecutive years without finding a hornet to consider it eradicated.

Spichiger is also encouraging the public to build and monitor traps starting July 1 when worker hornets are expected to emerge. More information on building traps can be found at bit.ly/38LSWo9.

“We’ve made some progress in not just fighting this, but in fighting other invasive species as well,” he said. “We really appreciate your assistance.”

To report a suspected Asian giant hornet detection, visit agr.wa.gov/hornets, email hornets@agr.wa.gov or call 800/443-6684.