Scientists are calling for help from the public to eradicate the invasive Asian giant hornet species that has been discovered so far in the state of Washington State and British Columbia, Canada, over the past two years.
The Asian giant hornet is the biggest known hornet in the world. The hornet can grow up to 2 inches long with a curved stinger long enough to puncture a bee suit.
Scientists at the U.S. Department of Agriculture and the B.C. Ministry of Agriculture, Food, and Fisheries said people can help by laying out a mix of one cup of brown sugar and one cup of water to lure and trap these hornets, as the end of the species’ hibernation period approaches in April.
The trap only needs to be checked once every two weeks, and unlike the previous recommended traps of wine and orange juice, it is more economical.
Asian giant hornets or Vespa mandarinia are native to East Asia. The ecosystems of North America depend on honeybee colonies and other local insect species, and giant hornets pose a major threat, as the bees have no natural defense against them.
Two years ago, they were discovered in Nanaimo on Vancouver Island, in Canada, where a nest that was found was destroyed. More recently, the giant hornets and their nests have been found in Washington, and across the Fraser Valley in British Columbia.
Murder hornets were sighted in 31 places, and one was tracked, then the nest destroyed.
They can grow up to 2 inches long, have a wingspan of up to 2.75 inches, a quarter-inch-long stinger, and a large orange head. Although they don’t normally deliberately attack humans, a paper published by the University of Washington describes the sting of a murder hornet as “excruciating” and notes that unlike honeybees, hornets can sting repeatedly.
“We would like to use the public’s eyes to report sightings because we just don’t have enough resources to be everywhere all the time,” said Paul van Westendorp, an apiculturist with the B.C. Ministry of Agriculture, on Wednesday, March 17.
“If you have a trap near your house and you find some unusually large wasp or hornet-like creature in there, all that I would suggest is call [authorities] and we will deal with it.”
Last year, 1,200 Washingtonians hung traps and checked them in their own time, and half of confirmed detections came from community members.
With cooler temperatures in winter, queen hornets will scatter to seek shelter, and the males naturally die off. The queens will emerge again usually in March and April, seeking a nest.
Trapping the hornets follows the weather cycles, and around July is optimum for setting the traps, as the worker hornets are becoming active.
In October 2020, entomologists from the Washington State Department of Agriculture (WSDA) located the first known Asian giant hornet nest in the country in Whatcom County. Using a vacuum, entomologists successfully removed a total of 100 hornets from the nest. Across the border in Canada, only 6 hornets were found in the Fraser Valley in British Columbia in 2020.
If left unchecked, researchers at Washington State University predict that the hornets could invade all of Washington and Oregon by 2040.
Although the hornets generally do not bother humans, there is risk involved to hanging traps. But some experts say the bigger risk is having these dangerous pests go undetected.
“The real danger is having something that cause you a really serious world of hurt unbeknownst to you living on your property,” said WSDA’s Sven Spichiger. “So to me, hanging a trap actually protects you.”