Invasive Asian giant hornet discovered in Washington state

By Jean Lotus
State agricultural pest eradicators wear protective suits while searching for underground nests of invasive Asian giant hornets. Photo courtesy of the Washington State Department of Agriculture
State agricultural pest eradicators wear protective suits while searching for underground nests of invasive Asian giant hornets. Photo courtesy of the Washington State Department of Agriculture

DENVER, May 2 (UPI) -- Washington agriculture authorities are asking residents to be on the lookout for an invasive giant wasp with an "excruciating" sting that attacks honeybee colonies, leaving thousands of bees without heads.

"The Asian giant hornet been called the most venomous, intimidating insect in the world, and it even scares away other hornets," said Timothy Lawrence, director of the Island County extension office at Washington State University.


Asian giant hornets originating in South Korea were first reported last fall near Vancouver Island in British Columbia. Then, residents in Blaine, Wash., near the Canadian border, used an invasive species app to report wasps that were confirmed to be Asian giant hornets from Japan, the state agriculture department said.

An infestation of the new giant wasps could be devastating for beekeepers who bring their hives to the state to pollinate Northwest Pacific crops like cherries, blueberries and apples.


"Commercial beekeepers have 300 to 400 hives in the area. They may not want to go to certain counties if this infestation takes hold," Lawrence said.

In Europe, the invasive yellow-legged Asian hornets, which also kill honeybees and other pollinators, has caused millions of dollars' worth of damage to crops in France and elsewhere after they gained a foothold.

The Asian giant hornets, also called "yak-killer hornets," measure about 2 inches long and have an orangeish-yellow face with large black eyes.

"They're like something out of a monster cartoon," Susan Cobey, a bee breeder with WSU's Department of Entomology, said in a statement.

The Asian giant hornet's sting is described as excruciating, and they can sting repeatedly. Their quarter-inch stinger can penetrate beekeeping protective clothing, a state agriculture department warning said.

The wasps are dangerous if their underground nests are disturbed, or if a food source is threatened. Their venom, seven-times stronger than that of honeybees, can cause anaphylactic shock, but also can be lethal to people who are not allergic if victims are stung repeatedly.

"They give a warning before they sting. They snap their mandibles and make a clicking sound," Lawrence said. "But if you stick around to notice that, you're probably already in a world of hurt."


The wasps might have hitched a ride to the Pacific Coast in a container ship, but also could have been imported intentionally as an ingredient for a folk recipe for wasp venom in alcohol, made popular by Internet bodybuilders, entomologists think.

The life cycle of the Asian giant hornet begins when a queen emerges from hibernation in April and feeds on plant sap and fruit, looking for a spot to build an underground nest, according to state fact sheets. By summer, queens have created a colony of worker wasps that spread out to seek food.

At the end of the summer, the hornets enter a "high-protein demand" phase when they attack honeybee colonies, killing off the adults to feast on the immature brood of pupa and larva, scientists say.

The hornets will leave piles of dead bees, most of them headless, outside their beehive. A few dozen hornets can kill an entire colony of 30,000 bees in a few hours.

Scientists will be hunting for queens this spring, wearing special reinforced suits from China, said Rian Wojahn, eradication coordinator for the pest program at the Washington State Department of Agriculture.

"The suits are made out of thick foam material with everything -- boots, gloves, hat -- attached," Wojahn said.


Trappers have set out bait bottles, filled with orange juice and rice wine, in coordination with state beekeeper clubs.

The trappers will use heat cameras to find underground nests, Wojahn said. Wasps will be sedated with carbon dioxide fire extinguishers, and pest workers will dig out the nests.

Local entomologists worry about native bees and other pollinators that also might be threatened if the Asian giant hornet gets established, said Todd Murray, a Washington State University extension entomologist.

Global economies and travel between faraway parts of the world are making invasive species more common, Murray said.

"When we do get establishment of a new invasive species, its' a 'forever change,' and becomes something we learn to live with," he said. This is definitely a hornet I don't want to learn to live with."

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