Advanced radio tracking technology is successfully hunting down yellow-legged hornets (Vespa velutina) and their nests in Auckland, boosting the fight against the insect pest.

The small radio trackers imported from the Netherlands have successfully helped find queens, workers, and three hornet nests to date, and are becoming a very important tool in our eradication operation.

Biosecurity New Zealand’s on-the-ground team lure worker hornets to a feeding station and observe their movements to help estimate nest proximity. Tiny transmitters weighing less than 160mgs are then attached to the workers, and the team are then able to track their flight path back to the nests using signals from the transmitter to a radio receiver.

Thermal drones had also been used to pinpoint where nests are, and to assess the population inside.

This tracker technology is expected to be especially useful as summer progresses and hornets are likely to build larger secondary nests up in trees where they’re less visible to ground searchers.

Video footage of the trackers in action can be viewed here.

The fantastic response from across the country and importantly, from the local community where these hornets have been found, continues. Teams on the ground have engaged with schools and community groups and there are families making traps and putting them in their backyards. A guide to making traps is available here.

Through our groundwork, the recent use of the tracking devices and public involvement, we have so far found 43 queen hornets and 30 of these were found with nests. Our focus is on locating and destroying queens to stop them producing a new generation of hornets. At the end of autumn, workers (approximately 600 have been found to date and destroyed) die, but any remaining mated queens can hide over winter and emerge the following spring to build nests and raise their young.

Response facts and figures:

• All detections have been confined to the Glenfield and Birkdale areas of Auckland.
• As well as trackers, there are 965 traps currently in an area out to 11km from detection locations.
• Ongoing daily ground surveillance takes place across the North Shore, with over 8,300 visits so far to individual properties.
• A public awareness campaign is running nationwide throughout summer.
• Two specialists from the United Kingdom with experience managing yellow-legged hornets are currently in New Zealand, observing the response operation and sharing their expertise, including their use of the tracking technology.

All growers - especially those in Auckland - are urged to continue to be on the lookout for yellow-legged hornets or nests, especially near any hives they may have on their property. Report sightings immediately to Biosecurity New Zealand on 0800 80 99 66 or make an online report here.

There is also a video and various resources available on our dedicated response page here.

Manufacturer information about the hornet tracking system is available here.