Asian giant hornet not expected to be in Virginia for the foreseeable future

While there have been a couple of sightings of Vespa mandarinia — commonly called the Asian giant hornet — in North America, there have not been any sightings in Virginia or on the East Coast.

The hornet was first seen in North America in fall 2019 when it was spotted in Vancouver, British Columbia, Canada, and was subsequently destroyed. At the time, no further Asian giant hornet adults were found in the Canadian province. In November 2019, a single hornet was seen around 10 miles away in British Columbia.

In winter 2019, less than 40 miles from that same nest, one dead Asian giant hornet worker was found in Washington state. That worker appears to be from a local nest or, less likely, blown in by Pacific winds. The nest was destroyed and no hornets have been observed in 2020.

“If it is discovered to be established in the Pacific Northwest later this summer, both American and Canadian governments will work hard to eradicate it. Even if that fails, the spread of the wasp is less than 40 miles a year, and it would be years before it spread from Canada to the East Coast. However, we should remain vigilant about all invasive species, such as the spotted lanternfly,” said Tim Kring, professor and head of the Department of Entomology in the Virginia Tech College of Agriculture and Life Sciences. “We have several large hornets less than 1.5 inches long that might be confused with the Asian giant hornet.”

Once established, the Asian giant hornet can be a significant problem for beekeepers, as it takes advantage of hives by attacking them in the spring and fall when they are more vulnerable. In the spring the hornets grab individual worker bees, then in the fall, they attack a hive en masse, killing the worker bees and feeding on the bee brood within the hive.

Vespa crabro, or the European Hornet, is commonly found in parts of the United States, including in Virginia. It has a few common identifying features but is significantly smaller at around one inch, versus two, when compared to the Asian giant hornet. The European hornet does not pose a major threat to honeybees and is a generalist predator.

While nearly as large as the Asian giant hornet, Sphecius speciosus, or the cicada killer, is not in the same insect family as the Asian giant hornet and is specialized to hunt annual cicadas, and to a significantly lesser extent, periodical cicadas. The cicada killer is not aggressive toward humans and does not sting often. It is common throughout the United States, especially in southeastern states including Virginia, and can be easily mistaken for the Asian giant hornet.

Another relative of the Asian giant hornet is Vespa velutina, or the Asian hornet, and also primarily feeds on domestic honeybees. The Asian hornet is not known to be in the United States and is found in Europe, India, and China.

At around one-inch-long, the Dolichovespula maculata, or the Baldfaced Hornet, is common in the United States and throughout Virginia. The biggest differences between the Asian giant hornet and the baldfaced hornet are the size and color of the hornets. The baldfaced hornet is a generalist predator that feeds on flies and caterpillars.

Virginia Cooperative Extension is always interested in any invasive species, including the spotted wing drosophila, spotted lanternfly, and Asian longhorned tick. Extension does not expect the Asian giant hornet to be seen in Virginia in the foreseeable future, but if you see anything unusual, take a quality photograph and send it to your local Extension office. If the dead specimen can be safely collected, you can mail it to your local Extension office.

- Written by Max Esterhuizen