Murder hornets in PNW? Washington officials say 2022 will be a test year
The hunt for Asian giant hornets remained quiet in Washington after the third nest was eradicated in 2021, but that doesn’t mean they’re gone
PORTLAND, Ore. (KOIN) — Washington state officials hope there will be a little less buzz when it comes to Asian giant hornets in 2022. In other words, they hope the work they’ve been doing to eradicate invasive species in 2021 will pay off.
In August and September 2021, the Washington State Department of Agriculture located and exterminated three Asian giant hornet nests. There have been no further detections since the nests were removed.
The researchers also determined in early January that the three nests were linked to the nest they eradicated in 2020. Karla Salp, public engagement specialist for the WSDA, said it was an encouraging sign that he n there were no other hives.
“It shows that they all came from this nest, and more importantly, there was no interbreeding with other nests that we hadn’t detected. So if we had obtained evidence of Cross-breeding DNA, we would have known there were other nests there,” she explained.
Salp was careful to say that “lack of evidence is not evidence of lack”. In other words, just because they don’t have evidence of other nests doesn’t mean there aren’t other nests out there.
However, another positive sign was that in every eradicated nest in 2021 there was a mature queen inside and she was the only queen. This means that WSDOT reached the nests in time before the queens could breed new virgin queens that could potentially come out and start new nests.
Salp attributes this to timing. The 2021 nests were discovered in August and September, earlier in the season. The 2020 nest was eradicated towards the end of October and there were nearly 200 queens in that nest at the time. Salp said some of them might have flew off and started the new nests they found the following year.
Right now, in January, the hornets are overwintering, which means they are quite dormant. The queens begin to emerge in early spring, and the WSDOT says this will be what really determines whether their efforts to defeat the invaders have truly succeeded.
Salp said the WSDA would begin developing a plan for 2022 in late winter or early spring. So far, all the hives have been discovered in the same area east of Blaine, Washington, leading WSDA to hope they haven’t spread far.
WSDA used radio trackers to locate the nests. Either they go out and capture a hornet after receiving a sighting report, or they use a live hornet caught in a wasp trap. They will cool the hornet to a temperature where they are not active and attach a radio tracker to them and let them go. They will then follow this tracker to locate the nest.
Salp said there has been a lot of public interest in wanting to help track invasive insects and she attributes this to much of the WSDA’s success.
“We’ve found that people, just by keeping their eyes open and reporting sightings to us, you know, getting a picture of what they see and sending it to us, it’s actually more effective than our entrapment,” she said.
She said the WSDA gets more detections from public sightings than from the tracking system itself.
Asian giant hornets, which are invasive pests not native to the United States, feed on other insects such as bees. A small group of hornets can wipe out a hive of bees in just a few hours. This is why the WSDA is so determined to remove them from the area.
Salp said things calmed down after the resolution of the third nest in 2021, but she said you never know if they will reappear in 2022. She encourages anyone who sees an insect they think is an Asian giant hornet to take a photo of it and report it to their state’s invasive species manager.
In Washington, you can report a suspected Asian giant hornet sighting in line or by emailing [email protected] or calling 1.800.443.6684.