Biosecurity New Zealand urges Aucklanders to be on the lookout for yellow-legged hornets or nests, as numbers of the pest keep climbing.

Thirty-three Queen Hornets have so far been found in the Glenfield and Birkdale areas of the North Shore - two more since Friday - 21 with developed nests or signs of nests.

Biosecurity NZ north commissioner Mike Inglis said the hornets had not spread yet from Glenfield and Birkdale.

Officials have put up signs within one kilometre of where the hornets were initially found, including in the suburb of Milford, alerting people to the invasive insect.

Biosecurity NZ north commissioner Mike Inglis. Photo: RNZ/Marika Khabazi

Inglis said that was just to raise awareness of the issue, rather than to signal the hornets had spread.

"All we are doing is continuing to engage the public, get some signage up.

"If you spot one, take a picture of it - if it's a nest, take a picture of it. Don't disturb it, contact our hotline and our expert staff will be out to deal with it."

Inglis said teams had set more than 617 traps to eradicate the invasive insects, which were nearly twice the size of the common wasp and could wipe out bee colonies.

Trapping has already been extended out to 5km from the hornet detections, with a combination of carbohydrate and protein traps.

Inglis said staff would consult the technical advisory group overseeing the issue over extending further.

The insect traps hanging from trees around some locations in Auckland. Photo: RNZ/Marika Khabazi

He said tracking technology from the Netherlands had arrived, which focused on worker hornets and tracked those hornets back to the nest.

There were signs of worker hornets operating and more were likely to appear over the next 4-6 weeks, he said.

"We'll start to find some worker hornets as well, in terms of they're going out and building a secondary nest, they go foraging generally within the same area."

He said Biosecurity NZ had received more than 4860 messages from the public so far about the hornets.