Asian giant hornets have gained a fearsome reputation in the United States thanks to their size, strong sting, and fondness for beheading honeybees.
The Vespa Mandarinia, better known by the nickname “Murder Hornet,” is the largest hornet in the world, and US scientists and federal agencies are preparing for a new season.
Efforts to track down and eradicate the giant wasps are being led by officials in Washington state, where they were first spotted in December 2019.
The Washington State Department of Agriculture reviewed two reports of hornets near the town of Blaine, marking the first sighting of the country.
Canadian officials found the species in two locations in British Columbia in the fall of 2019.
Last year, both regions confirmed additional hornet sightings, leading to the first extermination of a giant hornet nest in the United States last October. A nest was found in a tree in a house in Blaine and 98 worker hornets were killed.
They are described by the wildlife authorities as an invasive pest. As the name suggests, they are typically found in tropical areas of South and East Asia.
Female Asian giant hornets can reach lengths of nearly 2.5 inches, with workers usually being slightly smaller. The flying insects have bright orange heads and large eyes, and their bodies have a characteristic pattern of yellow, black, and brown stripes.
Because of their size, the hornets can release more venom than the typical wasp and can stab repeatedly with enough force to pierce a beekeeper’s protective clothing.
Asian giant hornets live in social colonies established by a single queen and usually build their nests underground, according to the National History Museum in London.
They are known to feed on other insects, with their ruthless siege of beehives, often used to justify the nickname “murder hornet”.
Scientists have documented that Asian giant hornets use scouts to locate beehives and then set pheromone markers for the other hornets to follow. The wasps then enter what is known as a “slaughter phase” in which they kill the adult bees by decapitating them before taking larvae for food. This new source of food is aggressively guarded.
Experts say that an entire beehive can be wiped out by a few hornets in a matter of hours. European honey bees have no natural or advanced defense against such an attack and an influx of giant wasps could pose a major threat to the bees and the plants they pollinate.
Despite their reputation, the hornets are not believed to be deliberately aggressive and generally not attack people or pets – although they will sting if they feel threatened.
A report from North Dakota State University suggests that deaths from hornet stings in humans are “fairly rare,” with most related to allergic reactions. It is not clear how the insects got to British Columbia and Washington, but trade routes are likely.
The Washington State Department of Agriculture says residents could join the community scientist trap plan to eradicate the hornets. It is suggested to catch them between July and November when workers are more likely to be active.
“Trapping at other times is unlikely to catch Asian giant hornets because of their life cycle and unnecessarily killing local insects,” it warned on its website.
The agency said it will continue to use orange juice and rice cooking wine in its traps this year, but suggested that citizen scientists in Washington could also try a brown sugar-based bait. Detailed instructions on how to create a bottle trap have been posted on his website.
Residents are advised to cut a star-shaped opening in the bottle, which is baited with alcoholic rice that cooks wine and orange juice, or dark brown sugar and water. The bottle should stand 6 feet tall on trees, near forest edges if possible.
The location should be logged on the agency’s Hornet Watch Trap Submission Map. It needs to be emptied and refilled once a week for the entire 22 week season.
The department said, “If you find a live Asian Giant Hornet in your trap if you investigate – do not treat the trap. Contact WSDA immediately at 1-800-443-6684. All you need to do is catch any suspicious Asian Giant Hornets Report.” If you suspect you might have found one in your trap collection, take a picture and email it to aghtrapping@agr.wa.gov along with the date and trap number. Keep the copy until the WSDA confirms your find. “
The agency added that its traps would focus on Whatcom County, where the wasps were discovered in 2019 and 2020. Officials said they were particularly interested in hearing from citizen scientists in Whatcom, Skagit, Iceland, San Juan, Jefferson, and Clallam counties.
A dead Asian giant hornet. US scientists and federal agencies are preparing for a new season of insects in the coming months.
ELAINE THOMPSON / POOL / AFP / Getty Images
