The full contents of the first “murder hornet” nest discovered in the U.S. have been revealed, and they’re unsurprisingly terrifying. On Tuesday, Washington state officials announced they found over 500 Asian giant hornets in the nest, including dozens of not-yet-fertile queens that were primed to mate, wait out the winter, and then start their own hives next year. Thankfully, nearly all hornets in this nest were exterminated.
Scientists made the discovery in late October, inside a tree on a private residence in Whatcom County. Entomologists from the state suited up in thick protective gear as a precaution against the invasive hornets’ long stingers and venomous spit before vacuuming out an estimated 100 hornets into canisters (13 were captured alive in a net for future study). Then they flooded the nest with carbon dioxide in an effort to kill or knock out the remaining hornets and cut open the tree. The nest was then taken to cold storage so it could later be opened up and studied safely.
Even with the freeze session and multiple applications of carbon dioxide—a synthetic version of how some bees naturally defend themselves against the hornets—most were still alive when the nest was finally opened. Ultimately, the scientists tallied up six comb layers, containing over 700 cells used to store growing hornets; six undeveloped eggs; 190 larvae; 168 pupae (the next stage of bug life after larva); 112 worker hornets, nine drones (males whose main function is to mate with the queen); and 76 queens, with all but one likely virgin new queens that hadn’t mated yet.
Had these queens survived, they would have emerged from the nest, mated with a drone and become fertile, then found a place to survive the winter so they could emerge next spring and start the cycle anew. The worker hornets, meanwhile, would have died in the abandoned hive over the winter; such is the cruelty of social insect life.
Thankfully, the find seems to have been made in time to stop these hornets from spreading elsewhere in the area, before they would enter a period of feeding colorfully known as their “slaughter phase.” Scientists have been worried about the invasive species encroaching farther into the state and elsewhere, following their discovery in Washington last winter. Asian giant hornets, while not usually aggressive toward humans, are a major predator of honeybees, and it’s feared they would threaten the already-fragile farmed population of bees in the U.S. if they became established here.
So far, despite hundreds of alleged sightings in multiple states since last year, only a few reports have been genuine, and so far only in Washington state. But that doesn’t mean that scientists in the area are resting easy. They’ll keep looking out for worker hornets to trap up until Thanksgiving, in order to track them back to hives, as they did for this first one. And even if they don’t see any more this year, they plan to keep traps out for at least the next three years, to ensure the hornets are truly gone. For now, it’s still hoped that these efforts can eradicate the hornet before they make the Pacific Northwest their new playground.