WSDA entomologists continue to track and study Giant (aka Murder) Hornets

A hornet worker sporting a new,
ultra-light solar powered tracking tag

Washington State Department of Agriculture (WSDA) entomologists recently returned from their second trip to Korea this season, completing a second season of collaborative field research with Kyungpook National University on the northern giant hornet in its native range.

The goals of that project are to learn more about hornet foraging behavior (to better deploy the food-based traps currently used), colony cycles and diurnal behavior patterns, and potential dispersal behavior of newly produced queen hornets.

 
The latter is particularly important for establishing response areas upon detection of hornets in new areas. The season was wracked with challenges, including a typhoon that impacted some of the data collected. 

Nevertheless, the team returned with over 200 tethered flight mill trials (a way to estimate the physiological maximum of queen hornet flight ability), 250,000 data points for worker hornets entering and exiting their nests, and over 120 hours of camera footage of activity outside of the hornet nests.

A male hornet pausing for a juice
break while attached to a flight mill

They also collected months of data from hornets tagged and moving throughout their foraging areas, although this data is compromised by the hornets literally chewing their tracking tags to pieces.

They also tested new, smaller tags that are not yet commercially available – the tags seem to have promise for studying many different insect species.

All told, the team assembled a very large data set that will provide unique insights into hornet biology, even given the many setbacks of 2023, which was not a great year for hornets in the local area.

WSDA has placed around 800 traps in Whatcom County where the hornets were first discovered in Washington state. The program is continuing to monitor and check traps for hornets. They will begin removing traps in December.

There have been no confirmed detections of northern giant hornets so far in 2023.

It is still important to be on the lookout. Dead or alive, northern giant hornet reports are helpful. In December 2019 and September 2020, dead hornets were collected. One hornet was found on a porch, and the other was inside a lantern-style electric yard light that had a paper wasp nest inside.

British Columbia continues to do surveillance with traps and urge beekeepers to do the same. They are wrapping up their season. This year they have had no northern giant hornet detections.

Any confirmed report can help guide trapping efforts, and collected hornets can aid in future research. If you think you have seen a hornet, report it online, email hornets@agr.wa.gov, or call 1-800-443-6684. Include a photo if you can safely obtain one. If the specimen is dead, you may collect it and wait for our response.

The so-called "murder hornets" can be lethal to humans with venom allergies and wipe out an entire honeybee colony in two hours.