‘Murder Hornet’ Eradication is Relief to US Honeybees
A Northern Giant Hornet removed from a nest. Photo courtesty: Washington Department of Agriculture.
Five years after the headline-grabbing “murder hornet” (Vespa mandarinia, renamed the northern giant hornet in 2022) was first spotted in Washington state, the U.S. has declared the invasive species eradicated.
The Washington State Department of Agriculture and the U.S. Department of Agriculture made the announcement Wednesday. It follows three years without a confirmed detection of the hornet. Four nests were destroyed in 2020 and 2021.
While the number of nests was low, Professor Mike Goodisman, whose lab studies social insects and invasive species, explains that had the number grown, eradication would have been increasingly unlikely due to the potential exponential growth of the population.
"Each nest is started by a new queen. One new queen can start a new nest, but the colony she produces can produce 100 new nests. Because of how they reproduce, it could grow from 100 to 10,000 the year after that, and then from 10,000 to one million."
Goodisman says that social insects are more difficult to eradicate. However, traps and tracking methods allowed officials to contain the population in the Pacific Northwest. While the murder hornet is not the only invasive hornet species in North America, its threat to the already-declining honeybee population spurred action. Murder hornets can clear out a honeybee hive in 90 minutes, and Goodisman says the brutality of these attacks earned the northern giant hornet their nickname and is instantly recognizable.
"When murder hornets attack a honeybee colony, you'll find hundreds to thousands of decapitated honeybees," he said, adding that although murder hornets eat a variety of insects, they "have a taste for honeybees."
In the murder hornet's native Asia, the honeybee population has developed a defense mechanism to swarm and surround the attacking hornet, but North American honeybees are defenseless. This elevates the threat of a possible invasion, with the potential for a widespread impact on our food supply.
"A threat to the honeybee population would be a commercial disaster," Goodisman said. "Honeybees are critical in agriculture for pollinating a great variety of the foods we eat, and if we don't have these pollinators, then we wouldn't have many of the foods — fruits especially — that we are used to."
The eradication of the hornet is a significant achievement, but Goodisman says it's not a foregone conclusion that they will not reemerge. Because social insects, like murder hornets, can hibernate in various materials, cargo ships and other commercial transportation can unknowingly bring invasive species worldwide. He explains that officials will continue to set traps and employ additional tracking methods to ensure the population remains eradicated in the U.S.
If murder hornets come back, humans are not at immediate risk. Like the bald-faced hornet and the true hornet, which live in Georgia, murder hornets typically leave humans alone unless provoked, Goodisman says, but their larger-than-normal stingers cause more pain and are more harmful to small animals.