Hope all of you are doing well and staying safe. You probably are glad that, even during these uncertain and difficult times, we can stay sane in the company of our bees. I just wanted to provide a quick update regarding the Asian Giant Hornets that were in the news once again. You may recall an Asian Giant Hornet alert that I sent in March 2020.
What are Asian Giant Hornets (AGH)?
The Asian Giant Hornets (Vespa mandarinia) are native to Asia. They are the world’s largest hornet measuring about 2 inches long with a wing span of 3 inches and distinct large orange-colored heads. They mostly nest underground and sometimes in dead logs. They generally prey on different types of insects (beetles, praying mantis, etc.), but may seek honey bee hives during summer and fall when their protein needs are high to feed their young. Their coordinated attack as a group could be devastating to honey bee colonies, as only a few hornets can decimate an entire honey bee colony in few hours. They are generally not aggressive towards people and do not pursue them, but can sting if threatened or if their nest is disturbed.
Should we be concerned about AGH?
We should not panic about AGH at this time as they have not been reported to have established in the Pacific Northwest or US, but we should be vigilant. There are no confirmed reports of AGH in Oregon. A couple of hornets were found in two different locations in northwest Washington closer to the Canadian border during 2019, but there have been no further reports of AGH sightings in 2020 (as of May 15). As AGH is a potential threat to honey bee colonies, we need to make sure that they are not established in our region/country by active surveillance and eradication measures.
What to do if you think you have indeed seen an AGH or suspect AGH attack on your colony?
Since the recent media reports, concerned beekeepers, master gardeners, and citizens have been contacting ODA, OSU, OSBA, and other relevant groups for updates and to report potential AGH suspects. Please keep in mind that there are several confusing look-alikes of AGH in the Pacific Northwest, such as sawflies, cicada killers, and other wasps, and it is easy to panic if you see one of these large hornet look-alikes. If you are confident that you have seen an AGH or you suspect an AGH attack on a bee hive, then please report the sightings/incident to ODA at: oda.fyi/HornetReport or call (503) 986-4636. If possible, please take a picture of the suspect from a safe distance and upload to the ODA reporting site listed above. You can also report the sightings to us at OSU (Honey Bee Lab or Pollinator Health Extension).
Below are links to some good information on Asian Giant Hornet biology, identification, and monitoring:
www.oregon.gov/ODA/shared/Documents/Publications/IPPM/AsianGiantHornet PestAlert.pdf
cms.agr.wa.gov/WSDAKentico/Documents/Pubs/846-SizingUpAsianGiantHornet.pdf
agr.wa.gov/departments/insects-pests-and-weeds/insects/hornets
In addition, a new publication: Asian Giant Hornet: A potential threat to honey bee colonies in Oregon
Ramesh Sagili
NOTE: In addition to what Ramesh provides here, Lynn Royce has written that she recently saw a video online of honey bees mobbing a Asian Giant Hornet, overheating it and thus killing it. Lynn says the video implied that certain honey bees learned to kill the hornet this way, which may be misleading in that it suggests that killing the hornet by overheating it is a new technique the honey bees have learned. As we know, the bees have long killed yellowjackets and others in this way. It works when there is but one wasp or hornet. This technique will not work, as Lynn puts it, “against a mob.”
Further details and comparisons with “look-alikes” are available at: www.aphis.usda.gov/aphis/ourfocus/planthealth/plant-pest-and-disease-programs/honey-bees/agh/asian-giant-hornet. And a National Geographic video (www.youtube.com/watch?v=w7zWGOGjLxs) may also be of interest here!