Officials with the Washington State Department of Agriculture held a press conference today to discuss the details about the first Asian giant hornet nest found in North America after dissecting it for more than a week.
The nest was found in a cavity of a dead tree east of Blaine after a WSDA team equipped a captured hornet with an electronic tracker and followed it back to the nest. An early morning eradication was carried out using a vacuum to extract live occupants and any remaining were subject to multiple doses carbon dioxide.
The section of the tree was transported to a walk-in cooler at a research center and cracked open to reveal the nest and its, many still live, occupants.
Here are some of details released today:
- The nest was just located over 8-feet above the ground in the tree.
- The nest was14 inches long by between 8 to 9 inches wide.
- 6 layers of comb made up the nest
- Combs are a cluster of cells which hold individual hornet larvae as they develop.
- ~776 cells total in the combs.
- 6 unhatched eggs in cells
- 190 larvae (most had fallen out of the combs into the tree cavity during the nest removal)
- 108 capped cells with pupae (thought to be new queens given their large size)
- Pupae are the stage after the larvae stage
- 112 worker hornets (female)
- 9 drone hornets (male)
- 76 queens
All told, more than 500 Asian giant hornet specimens in various stages of development were collected between the eradication process, subsequent dissection of the nest and area traps.
The pupae thought to be queens represent the those that could have established new nests next year.
It appears that if any queens left the nest prior to the eradication, it was only a few. It appeared they had gotten to the nest “just in time.”
“While it’s possible more queens could have left the nest earlier in the year, it’s unlikely.” according to WSDA entomologist Sven-Erik Spichiger.
Queens hibernate, typically underground, emerging in the spring to establish new nests according to the WSDA. They have to find a male to mate with to successfully start a new nest.
WSDA is starting to pull their traps and taking their sentinel bee hives down expecting to have all down by Thanksgiving. They will resume monitoring after the winter hibernation season early in the spring.
In the event no other hornets are found, WSDA will continue to trap for at least 3 more years to demonstrate the area is free from Asian giant hornets.