War on wasps in Bay

Wasps attacking honey bees. Photo/DOC

Introduced wasps are firmly in the Department of Conservation's sights this summer, as it expands its wasp control operations using the new wasp bait Vespex.

Vespex is a protein bait targeted only at wasps and is not attractive to bees. It was successfully piloted at five public conservation land sites in the South Island last year, reducing wasp activity at those sites by more than 95 per cent.

DOC scientist Eric Edwards said this year the Department would be using Vespex in priority areas where wasps were a threat to our native wildlife or presented a high nuisance factor.

In the next few weeks, DOC and its partners planned to bait wasps over 7,000 hectares at more than 30 sites. This included new sites in Auckland, the Bay of Plenty, the East Coast of the North Island and Whanganui.

In the South Island wasps would again be controlled at sites in the Nelson Lakes area, Pelorus Bridge and the Marlborough Sounds, and in the Abel Tasman National Park.

Mr Edwards said previously DOC staff could only respond to the wasp threat by locating and destroying individual nests, which was dangerous and time consuming.

"This bait station method means that the wasps can be controlled over a wider area because they take the insecticide back to their nests to feed their larvae. Many nests can be destroyed from a single bait station," he said.

One of the larger projects will be undertaken along 46km of the Abel Tasman Coast Track, in conjunction with Project Janszoon and the Abel Tasman Foreshore Scenic Reserve Fund.

"Bait stations are being placed near picnic areas and along tracks and huts to reduce the nuisance factor of wasps," he said. "Working together in this way means that birds, insects and people can get some relief from pest wasps. We hope this partnership approach can be adopted elsewhere in New Zealand."

Vespex was developed by Nelson based consultancy Merchento in conjunction with DOC, and was recently made available for public use.

Mr Edwards said he expects wasp control to increase over the coming years now that councils, community groups and individuals can also access the bait.

Wasps are one of the most damaging insect pests in New Zealand. Mr Edwards said their numbers could build up again each summer, so it was important that Crown agencies and universities joined the fight researching how to remove them in the long term.