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Asian giant hornet? Probably not!

A male Asian giant hornet, image credit Yasunori Koide via Wikipedia

The emergence of wasps and hornets this spring means a lot of Massachusetts residents are once again worried about the Asian giant hornet (Vespa mandarinia). Despite the stories in the media, there is still little to fear about this invasive insect in Massachusetts. Asian giant hornet has still only been found in Washington State and neighboring British Columbia, Canada. The Washington State Department of Agriculture successfully eradicated the nest they found in October 2020, and is planning  surveys and monitoring for 2021. Since Asian giant hornets cannot be spread through the movement of beehives, it is unlikely that this pest can spread very quickly from the west coast where it has been established.

That said, the overwhelming media attention directed towards “murder hornets” does have one benefit: it raises public awareness. That makes it likely that if Asian giant hornets are seen again, people will see them and report them, helping to prevent the establishment of this pest in the USA. While it is good to be on the lookout for invasive pests like the Asian giant hornet, keep in mind that there are several wasps and hornets found in Massachusetts that resemble this pest, but do not pose any risk to bees and do not attack humans, either. Here are three common lookalikes active during the spring:

1 ) The European hornet (Vespa crabro) is an introduced species that has been in the United States since the mid-1800s. It builds paper nests, while Asian giant hornets live in ground-based burrows. Though European hornets are larger than the common yellow jacket wasps we are used to seeing, they are much smaller than Asian giant hornet (less than 1 inch long, vs. AGH which gets closer to 2 inches long). Note the reddish-brown coloring on the head and upper body, and the black dots on the yellow lower body, a distinctly different pattern than on the body of an Asian giant hornet.

European hornet, image credit Larry Meade

2 ) The bald-faced hornet (Dolichovespula maculata) is another wasp you may see in Massachusetts. Although it may be aggressive to people who get too close to its papery, above-ground nest, it only attacks caterpillars, spiders, and flies. This species has a distinct black and white/pale yellow coloration that makes it easy to tell apart from Asian giant hornet, and similar to the European hornet, is under 1 inch long.

Bald-faced hornet, image credit Wikipedia

3 ) Another common look-alike is the Eastern yellowjacket (Vespula maculifrons). A species native to Massachusetts, Eastern yellowjackets are usually less than one inch long, and have a black and yellow striped abdomen and thorax, with a black and yellow head. They make nests underground and are attracted to sugary drinks, which can make them a nuisance at picnics, but they are also fierce predators of other pest insects, making them beneficial if you have a garden!

Eastern yellowjacket

If you think you have found an Asian giant hornet, especially if you have an apiary, please report it here. You can also visit our fact page for more information.


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