It’s not the first time that European honey bees and other pollinators in the United States have encountered invasive pests, with the parasitic Varroa mite being the most noteworthy. For years, researchers and beekeepers have wondered what the next invasive pest of concern would be. Perhaps Tropilaelaps mites, a parasitic mite that feeds on bee brood? Or an Asian honey bee, which is known to outcompete our European honey bees? Ultimately, it was the Asian giant hornet, making a confirmed appearance in Washington state during winter of 2019.
Asian giant hornets are extremely large hornets that range in size from 1.5 to over 2 inches long. They are equipped with relatively massive mandibles (teeth) and can easily tear honey bees in half. Usually, these hornets will not attack honey bees until late summer or early fall, when workers are feeding new queens and males within the colony that will emerge to mate in the fall.
When attacking a honey bee colony, the hornet excretes a pheromone marker on the hive to signal to others that the colony is its target. Up to fifty hornets attack the colony at once and can eliminate an entire honey bee colony in less than two hours. The hornets harvest bee brood to feed to their young and will defend the bee hive as if it were their own nest.
To date, Asian giant hornets have not been identified outside of Washington state and they are actively subject to quarantine measures by USDA’s Animal Plant Health Inspection Service (APHIS) and Washington Department of Agriculture. In addition to quarantine activities, USDA is actively supporting research efforts to develop interactive identification tools, map the hornet’s genome, and improve the efficacy of lures, traps, and monitoring programs.
If you believe you have encountered an Asian giant hornet, calmly leave the area, particularly if you are allergic to bee or wasp stings. To the untrained eye, these hornets can be easily confused with other insects. APHIS’ Asian Giant Hornet and Lookalikes Guide provides detailed photos and information for identification.
If you are in the state of Washington, sightings can be reported on the Washington State Department of Agriculture website. Outside of Washington, contact your state apiary inspector. If it is safe to do so, take a photo or collect a dead specimen of the pest to help experts identify the insect. Beekeepers—especially those located in the Pacific Northwest—can assist in tracking the possible movement of this pest by carefully examining the entrances of their hives for decapitated bees or for hives that have been taken over by hornets during the late summer and early fall seasons.
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My name is Paula Wolfel and I live in Austin, Texas. Last year we moved into a house that backs up to a Nature Preserve. And we started spotting these giant wasps/hornets. I kept asking around but could not find info. I finally got photos when I found one dead on my driveway. They arrived in late June and by late July we didn’t see them anymore. They love our lantana. This year they are back. But so is news about “Murder hornets” and “Asian Giant Hornets” - I have many photos but nowhere to attach them to send to you. Can I send them and get a confirmation that these are the same hornets that you all wrote about? And if so, we had them last summer. Could this be why we have had a decrease in bees on our property? Thank you!
@Paula Wolfel - thank you for your comment. We recommend that you contact your state apiary inspector. You can send your photos to the Texas Apiary Inspection Service.
Here is their contact information:
Texas Apiary Inspection Service
College Station, TX 77843-2475
Just found one in Michigan!
Very large and deadly looking,,,
We lived in Arlington, WA for 12 years, about an hour north of Seattle. So we've been following this story concerning the Pacific Northwest sightings. However, we now live in Chandler, AZ, a suburb of Phoenix. We saw one today and there is really no doubt as to what it was. What's more, it landed in our pool, stayed there for about 30 seconds and took off like it was no big deal. They're already much more widespread than given credit for.
Saw one in Connecticut at the Traders Joe’s while standing in line. I left the line and sat in my car until the line was gone.... Read about a sighting in PA, and DC on the east coast.
We have the Asian giant hornets on our property in Massachusetts. What is the best way to get rid of them?
@Darlene Bruch - thank you for your comment. Currently, the Asian giant hornet has not been identified outside of Washington state. Please consult APHIS’ Asian Giant Hornet and Lookalikes Guide. If you believe the specimen is an Asian giant hornet, please report your potential sighting to the Massachusetts state apiary inspector. We suggest you reach out to your local Extension office for advice on living with native insects, which are an important part of the local ecosystem.
I had one of these Again Giant Hornets in my garage about three years ago. I live in Western New York State.
I am not a beekeeper but found your report more effective than others because of your side-by-side photo comparison of the Asian bee and our honeybee. And the additional actual size photo blew me away!
Although I know this publication is focused on the U.S., I thought it would’ve been pertinent for this article to note the Asian bee was also found in two communities in nearby British Columbia, Canada.
I live in Covington, Ga. and I believe I saw one on my hummingbird feeder today.
All of the other bees disappeared when he showed up.
Even keeping the hummingbirds off the feeder.
My name is Pedro Paulo and I live in Methuen, Massachusetts. Today I was mowing my lawn and I without a doubt saw the single largest hornet I have ever seen. I know that this was not any regular hornet considering it's immense size and quicker than average flight speed. Not to mention it wasn't yellow it was a almost dark orange fitting all of the descriptions of the Giant asian hornet. These pest are not only in select places of our country they're spreading fast and at an alarming rate. Now I wanted to know of there is anything that is recommended to get rid of these invaders on your property?
I found one in lake stevens wa.
Those things are no joke to mess with!
We captured a murder hornet today, and it is still alive. We live in Freeland, WA. I think we should get this specimen to someone.
@Mary Sanders - thank you for your comment. Please consult APHIS’ Asian Giant Hornet and Lookalikes Guide. If you believe the specimen is an Asian giant hornet, please report your potential sighting to the Washington state apiary inspector. We suggest you reach out to your local Extension office for advice on living with native insects, which are an important part of the local ecosystem.
Hello, Four years ago a huge reddish-orange hornet slowly descended down from the sky as my nephew and I were sitting on our deck, the only reason I noticed it was because I glanced up at my hummingbird feeders which are hanging on a second-story window above the deck. I am pretty well versed in my entomology (my cousin has a Ph.D. from Cornell in entomology), this insect slowly hovered about three feet from my face, it was the size of my thumb. I thought it was a hummingbird because it dropped down vertically in a slow descent. I went to get my camera to take a photo, but unfortunately, it flew off after hovering around us for less than a minute. My neighbor across the street has honeybee colonies. Hearing recent stories on Asian giant hornets I "googled" photos of them and that is what we saw.
Can Bee Keepers use a simple device to prevent entry of larger predators? I envision a simple pipe elbow, probably 3/8" pipe, that would allow bees, but not the larger hornets to enter?
My limited knowledge of honey bees recalls the annual migration paths of western and eastern bees south through Central America, where they are replaced by their young, genetically programmed to return next year, either northwest or northeast states. This leads me to wonder if the predator hornets will follow those migratory bees south.
@Don Morrison - thank you for your comment. Some beekeepers use excluders on the entrances to beehives to keep predators out. APHIS has not tested this method, so we cannot provide a recommendation for or against excluders.
To your question about migration, some commercial beekeepers are called migratory beekeepers, because they move their bees for pollination contracts. However, honey bees do not migrate the way some birds and butterflies do.
Like honey bees, the Asian giant hornet overwinters when it gets cold, rather than migrating south. To date, Asian giant hornets have not been identified outside of Washington State.