Biosecurity New Zealand ramps up efforts to eradicate aggressive yellow-legged hornets as warmer months approach

Yellow-legged hornet (far left) compared to species established in New Zealand: (from left) the German wasp (Vespula germanica), the Asian paper wasp (Polistes chinensis) and the Australian paper wasp (Polistes humilis). Photo / Biosecurity New Zealand

Biosecurity New Zealand has confirmed the removal of 27 yellow-legged hornets as they ramp up their search for the invasive species across the North Shore of Tāmaki Makaurau Auckland.

The wider areas surrounding hotspots Glenfield and Birkdale are now under increased surveillance, with traps established as far north as Murrays Bay.

Biosecurity New Zealand commissioner north Mike Inglis said in a statement the results show the agency’s intensified response is working.

Twenty-seven queen hornets, seven workers and 17 nests have been eliminated to date, with genetic testing suggesting the population is still “small” and “contained”.

“In recent weeks, we’ve put in five times as many traps (now more than 600) across a 5km radius from detection sites and property-by-property searches under way within 200 metres of confirmed finds,” Inglis said.

More than 2100 properties have been searched for the invasive species with the support of teams from Auckland Council, Pest Free Kaipātiki, Plant & Food Research and Kiwifruit Vine Health.

“Those ground searches are paying dividends, with many of the nests and queens being detected through those intensive ground sweeps,” Inglis said.

Hornet traps have been established across a broad area of Tāmaki Makaurau's North Shore. Photo / MPI

Biosecurity New Zealand is now being guided by international approaches, bringing over a member of the UK’s hornet response team and importing advanced trackers from the Netherlands.

“That technology arrived in New Zealand this week. Under the guidance of a UK expert, we plan to use the technology to trace nests if worker activity increases over summer,” Inglis said.

The agency has urged Aucklanders to continue reporting sightings of the insects to help control and contain the spread of the hornets.

“We’ve had more than 4000 public notifications so far – an incredible contribution – and we’re very keen for this to continue,” Inglis said.

Suspected sightings can be reported online at https://report.mpi.govt.nz/pest/ or by calling Biosecurity New Zealand’s exotic pest and disease hotline 0800 809 966.

However, the public is being warned not to interact with the insects or their nests, as this may make it more difficult to track them.

Yellow-legged hornets (vespa velutina) are a threat to the local ecosystem, competing with our honeybee population and impacting honey production.

Mahurangi Honey’s Pete Johnston told The Front Page “it’s important to nip this in the bud now” before breeding season begins.

If the hornets are similar to the German wasp, Johnston expects they will begin mating in March and February, producing somewhere between 300 to 500 queens.