18 Sep 2015

Mite-y biocontrol

From Country Life, 9:15 pm on 18 September 2015

Landcare Research scientists are investigating a promising new biocontrol agent they hope will, over time, reduce the numbers of German and common wasps in New Zealand.

The wasps are significant environmental and economic pests.

They raid beehives, steal honey and prey on bees and, in vineyards, feed on grapes. Wasps also affect bird life by eating honey dew and the insects native bird species rely on. They pose a serious health risk to some people and  are a safety hazard to people working around them.

"With biological control what we are trying to do is reunite invasive organisms with their natural enemies from their native range." says Landcare Research biocontrol scientist Dr Ronny Groenteman.

During a recent study on the chemical ecology of European wasps, researcher Bob Brown discovered mites on the wasps. The mites appeared to attach themselves to wasps with their mouths and were located in areas difficult for the wasps to groom. Wing deformaties were apparent in infected wasps and heavily infected wasp colonies collapsed.

The first step of the project has been to identify why the mite is not already providing biocontrol and develop methods to ensure it can.  Further steps will ensure the mite is damaging to both species of  wasps, and that it will not pose a risk to honeybees, bumblebees and native bees.