Earring-Sized Transmitters Revolutionize War on Yellow-Legged Hornets

Earring-sized transmitters are being attached to worker hornets as Auckland's war on the insect pest continues. Biosecurity New Zealand said the new technology imported from the Netherlands had been a success in helping hunt down nests of yellow-legged hornets. Since October last year, 43 queen hornets had been found in the Glenfield and Birkdale areas on Auckland's North Shore. The pest, not known to be established in New Zealand, was considered a biosecurity concern due to the potential impact on honeybee and wild bee populations. Biosecurity Commissioner Mike Inglis said since Christmas, they had been luring workers to feeding stations and attaching small radio transmitters to them to observe their movements. "Tiny transmitters weighing less than 160mg are then attached to the workers, and we've been able to track their flight path back to the nests using signals from the transmitter to a radio receiver." He said they were also using thermal drones to pinpoint where nests were and to assess how big the population inside was. He said the technology had helped find hundreds of workers and three hornet nests in the past three weeks. "We've been able to destroy the nests with any queens and workers inside them. So far its been very successful. "Our focus is on locating and destroying queens to stop them from producing any new generations. "It's really important as we go through the summer, and more workers build secondary nests sometimes in higher up trees, that we continue to use these trackers alongside thermal drones, so we can locate these nests and destroy them, and hopefully the queen is in that secondary nest." Two specialists from the United Kingdom who had experience managing yellow-legged hornets arrived in New Zealand this week. "Every summer, they have incursions in Europe. In terms of using the technology to find secondary nests, particularly in taller trees, and how you deal with that we're really keen to get their advice. "They're already included in our technical advisory group, so we've built a good relationship. The first week they're here, they'll be involved in operations on the ground, working with our staff." Inglis said between $2m and $3m had been spent on the hornet eradication operation. He said the highest cost had been staffing. "We've got over 575 beekeepers engaged in an 11km search zone. We also engage beekeepers throughout the country, making sure there are eyes and ears on the ground. "There's up to 170 staff involved in this response at any given time. A variety of entomologists, people answering notifications from the public, staff on the ground, and contractors. "It's a heavy investment, but it's absolutely worth it to make sure we're on top of this and we eradicate the hornet." Biosecurity earlier said it had received almost 10,000 reports of possible sightings this summer. Biosecurity encouraged anyone who believed they had seen a suspected yellow-legged hornet, located a possible nest, or had taken a clear photo to report it online at report.mpi.govt.nz or by calling Biosecurity NZ's exotic pest and disease hotline on 0800 809 966.