Officials Declare the U.S. Free of ‘Murder Hornets’ in a Rare Victory Against an Invasive Insect
Five years after the first sighting in Washington state, intense efforts have eradicated the bee-killing hornets from the nation
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The name alone advertises that this insect is no joke: When the murder hornet was first spotted in the North American continent in 2019, entomologists were abuzz with worry and sprang into action to eradicate the invasive species.
Five years later—and after four nests were successfully destroyed—officials have declared a rare victory against the murder hornets for having exterminated them from United States soil.
“I’ve gotta tell you, as an entomologist—I’ve been doing this for over 25 years now, and it is a rare day when the humans actually get to win one against the insects,” Sven Spichiger, pest program manager with the Washington State Department of Agriculture, told journalists in a virtual news conference, per Gene Johnson of the Associated Press.
The murder hornet, more formally known as the northern giant hornet or the Vespa mandarinia, is originally from northern parts of Asia, such as Japan and China. It’s the largest member of the wasp family, measuring two inches in length. Their stingers deliver as much venom as a snake or seven times that of a honeybee. That makes its stings excruciating—one victim described the pain as “like having red-hot thumbtacks being driven into my flesh”—and it also makes them deadly. These hornets cause an estimated 30 to 50 human deaths each year in Japan, not all of them due to venom allergy.
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Moreover, giant hornets are known for their grisly methods for bee murder—unfortunate beekeepers have found their hives filled with bee carcasses, the heads ripped from their bodies. The rapacious killers can wipe out an entire bee colony within hours. Asian bees that have evolved alongside these predators have developed a curious way of dealing with their threats: Bees will swarm onto the hornet interloper and beat their wings until they cook their quarry alive. Such bee-induced temperatures have been measured to reach 115 degrees Fahrenheit.
Bees in the U.S. and Europe, however, have yet to devise similar defensive strategies. So, murder hornets pose a major threat not just to bees but also to other local insects. In areas where agriculture is a key economic driver and thus is dependent on pollinators, such murder hornet sightings can be a major cause for concern.
The first murder hornet sighting in the United States occurred in Whatcom County in northwest Washington, an area near the Canadian border that produces millions of pounds of raspberries and blueberries annually, according to Mike Baker of the New York Times. The report came just about four months after a separate murder hornet detection on Vancouver Island in British Columbia, Canada. Officials said the first hornet to reach North America likely stowed away in a shipping container or plant pots.
These first observations triggered a flurry of pest control activity to hunt the hunters. Pest managers created search grids and set traps. Trackers used thermal cameras to scan the forest floors in search of the hornet colony’s signature heat. For live individuals that were captured, entomologists tied tiny trackers onto their bellies using dental floss to suss out the location of their nests.
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Now, officials think their multi-year efforts have paid off in the state. There have been no confirmed sightings of murder hornets in the last three years, enough to clear the bar for a pronouncement of eradication, according to the definition of the U.S. Department of Agriculture. In October, officials received a tip of a giant hornet sighting 100 miles away from the original nest site, but they found no evidence confirming the report. But to be safe, the officials set up traps in the area and plan to continue the effort through next year.
“If the entire community hadn’t stood up and taken action, there is a real good chance that we would just all be living with the northern giant hornet, even for years to come,” Spichiger told the New York Times. “It is a very difficult task to eradicate an insect once it has become well-established.”
Experts are celebrating for now, but they recognize the achievement came only at great hassle. “It proves that the permanent removal of invasive species is possible, but only when given ample funding and public attention,” entomologist Chris Alice Kratzer, author of The Social Wasps of North America, tells National Geographic’s James Bittel.
The victory against murder hornets doesn’t mean they won’t pop up again in the future. Another wayward insect might find its way to U.S. shores again. “We will continue to be vigilant,” Spichiger tells the AP.
Elsewhere, humans are waging war against other kinds of invasive insects. Georgia and South Carolina are fending off the invasion of the yellow-legged hornet, a smaller relative of the giant hornet that also makes quick work of local pollinators. In northern Spain, officials are scrambling to contain the recent invasion of the southern giant hornet, a second blow to the beekeeping sector that’s already spread thin from the assault of another hornet, the Vespa veluntina.
In an increasingly interconnected world, where humans and trade crisscross the globe, species invasion will only grow more common without intervention. Models predict that insect invasions will increase by 36 percent between 2005 and 2050. Since the mid-1800s, at least 930 foreign insect species have snuck onto U.S. soil. The terrorizing hornet is yet one more instance in humankind’s long history of unwitting pest introductions, and it likely won't be the last.
