SEATTLE — The invasive species known as the “murder hornet,” recognized for its potent sting and its devastating impact on honey bee colonies, has been officially eradicated from the United States. This announcement comes five years after the hornet was first identified in Washington state, close to the Canadian border.
On Wednesday, both the Washington and U.S. Departments of Agriculture declared this successful eradication effort, noting that there had been no sightings of the northern giant hornet in Washington since 2021.
This achievement is attributed to a collaborative effort from local residents, who participated by setting up traps on their properties and reporting sightings. Researchers played a significant role as well; they successfully captured a live hornet, affixing a small radio tracking device to it with dental floss and tracing it back to a nest situated in an alder tree within the forest. Just as queens were starting to emerge, scientists effectively destroyed the nest, preventing further reproduction.
Sven Spichiger, the pest program manager for the Washington State Department of Agriculture and a seasoned entomologist with over 25 years of experience, expressed his elation during a virtual news conference. He remarked on how rare it is for humans to triumph over insects in such a definitive way.
The infamous hornets can reach lengths of 2 inches (5 cm) and were previously referred to as Asian giant hornets. They first garnered international attention in 2013 when outbreaks in China resulted in 42 fatalities and left 1,675 individuals injured. In the United States, about 72 individuals succumb to the stings of bees and hornets annually, as reported by the National Institutes of Health.
Initially, hornets were detected in North America in British Columbia, Canada, in August 2019, with confirmations in Washington state occurring shortly thereafter in December. A local resident in Whatcom County identified a specimen, and a beekeeper reported disturbances in hives, submitting hornet specimens in the summer of 2020. Experts believe the hornets may have arrived in North America hidden within plant pots or in shipping containers.
DNA analysis indicated that the hornet populations identified in British Columbia and Washington originated from different countries, suggesting no direct relationship. Notably, there have also been no confirmed sightings in British Columbia since 2021, leading the nonprofit Invasive Species Centre in Canada to declare the species eradicated there as well.
The northern giant hornets pose serious threats to native insects and pollinators, particularly honey bees. They are capable of decimating a bee colony in as little as 90 minutes by decapitating the bees and taking over the hive, using the bee brood to nourish their offspring.
With the ability to sting through most beekeeper protective gear, these hornets can inject nearly seven times the venom of a honey bee and can sting multiple times. At one point, the Washington agriculture department procured specialized reinforced suits from China in response to the threat.
To date, Washington has been the only state to report the presence of northern giant hornets, with four nests discovered by trappers in 2020 and 2021.
Despite the eradication news, Spichiger emphasized that vigilance will continue in Washington. He mentioned that entomologists will keep monitoring traps in Kitsap County, where there had been an unverified sighting in October, although trapping efforts and public reporting have not yielded any findings.
Spichiger also pointed out that other invasive hornet species could create challenges. In Georgia and South Carolina, officials are currently combating yellow-legged hornets, while southern giant hornets have recently been identified in Spain.
“Continued vigilance is essential,” noted Spichiger, reaffirming the commitment to keeping these invasive threats at bay.
