SEATTLE — The Asian giant hornet has resurfaced in the Canadian province of British Columbia, miles away from traps placed to contain it, suggesting that the invasive insect has already established itself in a broader territory than previously known.
Paul van Westendorp, a provincial apiculturist for British Columbia, said he had confirmed that one of the large hornets was discovered in the city of Langley this month. The specimen, collected after a woman killed an unusual-looking insect at her home, was found about eight miles north of where two other hornets were discovered last year near Blaine, Wash.
Since those initial troubling discoveries — the aggressive hornet’s first apparent foray into North America — American biologists have been placing traps throughout northwestern Washington State, while field workers in British Columbia focused traps along the border with the United States and in the community of White Rock. But the new discovery indicates that the hornet is not confined to that previously known territory, and that researchers may need to expand the scope of their work.
“This particular insect has acquired a larger distribution area at this time than we had thought,” Mr. van Westendorp said.
A necropsy of the insect is planned for next week to determine whether the hornet was a queen. Queens typically begin to emerge in the spring when they are looking for a place to establish a nest.
Beekeepers have been particularly worried that the Asian giant hornet, which can grow up to two inches long, could decimate beehives if it becomes established in North America. The hornet, which earned the nickname “murder hornet” among some in Japan, has an appetite for bee carcasses, conducting attacks on hives that can swiftly wipe out an entire colony by decapitating the bees one by one.
With a potent stinger, the hornet can be a public health threat if someone is stung repeatedly, and it is linked to up to 50 deaths a year in Japan.
Mr. van Westendorp said he was still hopeful that researchers, with the help of beekeepers and the public, would be able to hunt down and eradicate the new hornet before it could become established in the Pacific Northwest. But he also said the region, which appears to offer a hospitable habitat for the hornet, may need to prepare for the possibility that the insect is around for the long term.
One set of the hornets eradicated on Vancouver Island last year was not genetically linked to those found in Washington State, suggesting that hornets may be continuing to arrive on ships or cargo planes from Asia.
“These kinds of introductions will continue in the future,” Mr. van Westendorp said.
But even if the hornets do establish themselves in North America, Mr. van Westendorp said, most people should not worry too much about them, much as they do not usually fret about sharks when going into the ocean. He is concerned that people fearful of the hornets will kill bees and wasps that are critical to the region’s habitats.
In Washington State, some people have seized on fears of Asian giant hornets to post fake warning signs at trailheads claiming that the hornets were nesting in the area. The state said it removed at least three of those signs, and officials have made others available to be posted in areas where the hornets have been discovered.