WHATCOM COUNTY, Wash. — Officials with the Washington State Department of Agriculture (WSDA) announced this week that about 900 monitored traps in place in Whatcom County over the past 12 weeks have not captured any northern giant hornets (formerly known as Asian giant hornets). In addition, there have been no confirmed sightings either.
WSDA, in collaboration with USDA, has been testing different hornet attractants. The goal is to create a bait better at attracting northern giant hornets than the proven orange juice and rice wine mixture that has been used in bottle traps (link to YouTube video) since the invasive hornets were detected in a ground nest in Nanaimo, BC in 2019.
According to this week’s announcement, “Scientists are sampling four different lures. Some traps are emitting honeybee odors. A few traps contain bacillus volatiles, which are known to attract another closely related hornet. The last bait is two variations of hornet alarm pheromone. The pheromone is a foraging or defense compound the hornet can produce to signal assistance from hornets.”
It has been determined by molecular analysis of hornet excrement found in the last nest discovered in the east Blaine area that the hornets had been feeding on paper wasps and honeybees. This week’s announcement said that “the bald-faced hornet was high on the menu.”
Bottle trapping season begins in July when the worker hornets begin leaving the nests to forage and continues until November.
4 nests were located in Alder trees in east Blaine since the Nanaimo ground nest was discovered, 1 in 2020 and 3 in 2021.
WSDA officials continue to encourage residents to be on the lookout and report potential sightings via their Hornet Watch Report Form or by emailing them at email@example.com.
In the past, WSDA officials have said they will continue to set traps until there have been 3 successive years with no confirmed northern giant hornet captures.