The entomologists and researchers who led the Washington State fight against the Asian Hornet made some adjustments to the techniques they used to mark, track, and hope to eliminate invasive species.
At a press conference last week, WSDA’s management entomologist Sven-Erik Spichiger detailed the difference this year, as a new nest of the so-called “murder hornet” was discovered and eradicated.
First, WSDA has moved to a slightly different radio tracker produced by another company. This miniature technology is related to the Hornet, followed by the WSDA staff carrying the receiver. Last year, when another nest was located near Blaine, Washington, WSDA used dental floss to tie the trackers together, and Bumblebee seemed to be able to chew the material.
“We switched to the Kevlar line this year,” Spichiger said, noting that three bumblebees were captured and tagged this year. “The last bumblebee, the one that brought us back to the nest, doesn’t seem to be done in stages.” He said that the workers “can recapture the bumblebee and deactivate the tag after discovering the bumblebee nest, and maybe use it again. .”
Last fall, when a researcher at the University of Washington sought some equipment insight and guidance, the use of radio technology was explained for the first time.
Spichger said that scientists are cooling the captured bumblebees as little as possible. Once the bumblebee is caught in the net, it will be cooled for about 10 minutes, then labelled and released. The hard part is keeping up.
“When you try to track things that are flying very fast in the Himalayan BlackBerry, tracking events is as difficult as people think,” Spichger said, adding that this year’s new receiver is also lighter and easier to pass heavy swipes. carry.
A signal is completely lost. WSDA has been working very close to the Canadian border, and they think they have lost their signal when they point north. They shared radio tag frequencies and worked with their counterparts in British Columbia, who did some tracking on the Canadian side of the border. But the label was never restored or repositioned.
The nest was cleared from a rotting alder tree on August 25, which proved to be slightly different from the eradication in October last year.
“I would say this: This nest is more aggressive than the nest we encountered in 2020,” Spichger said. “Generally [the hornets] They are more interested in what we are doing, and they almost ignored us at the Bird’s Nest in 2020. “
Spichger said that warm temperatures may lead to aggression by the wasps-he is grateful that the safety equipment has played a role.
“Some of us who are working very nervously in the area were approached by wasps, and they did try to sting us this time,” he said. “But we are all happy to say that our Hornet suits worked well and there were no injuries.”
Spichger said that the Hornet “bounced directly off our cute suit”, which he described as a 1/4 inch thick soft foam covered with a white mesh net. The hornet stinger cannot penetrate the foam.
“They can be a little warmer,” Spichiger said of the bee suit. “They are quite uncomfortable, but it must be more comfortable than being stung, so we are always happy to make this trade-off.”
Spichiger shared some figures related to the contents of the nine beehives: 292 eggs, 422 larvae, 563 cap cells (the bumblebee that is about to produce), 195 staff members vacuumed or caught nets. There were no males. 1 queen bee. There are a total of 1,473 individual life stages, almost three times the size of the nest last year, which had about 500 life stages last year.
Spichiger and WSDA provided more gold nuggets from this year’s Hornet work:
- Officials will test the genes of several specimens to see if this nest is related to the nest that was eradicated last year.
- Spichiger doesn’t know why this nest is larger than the previous one. He said that the environment seems to be very suitable for the growth of bumblebees, maybe the weather this year is better. The data so far does not indicate that there are more nests, but he said, “We will continue to set traps.”
- WSDA needs to see three years of negative survey data and three years of no wasp report before considering the eradication of wasps. But biologically speaking, Spitzger has a large part of remote and overgrown lands that scientists cannot reach, so it may take years for the state to confidently declare 100% eradication of bumblebees.
- A subset of the new nest wasps will be retained to try to develop new traps.
- An owner did observe the Asian hornet attacking and taking away the bees that were foraging on her sunflower.
Watch last week’s full press conference here: