Scientists are fighting wasps with wasps
Scientists are looking at a parasitic wasp as the latest weapon in the war against wasps.
Landcare Research is exploring possible biocontrol agents, including a mite, to help control German and common wasps which cost the country’s primary industries about $130 million each year.
The most recent addition to the line-up is Sphecophaga, a species of parasitic wasp whose larvae feed off their host, eventually killing it.
The species was tried as a biocontrol agent against wasps in New Zealand in the 1980s, but so far has only established in a few locations. Research suggests this could be because the parasitic wasps were from the wrong region - sourced from Switzerland, Israel and the United States.
Victoria University recently discovered New Zealand’s dominant wasp species originate from the UK.
Landcare Research biocontrol scientist Dr Ronny Groenteman said this information was ‘‘a key piece of the puzzle’’.
‘‘Interactions between hosts and parasites are complex, and even more so when the host is a colony-forming insect as they rely heavily on chemical communication within the colony. These chemical signals serve as their language.
‘‘In order for Sphecophaga to go undetected in the nest, they must ‘speak’ the correct language, or dialect, in order to fool their hosts. Otherwise, wasps are so hygienic that they will rapidly remove any foreign intruders they detect,’’ Groenteman said.
In light of this new information, Landcare Research scientist Dr Bob Brown is heading to the UK in September to collect and bring back Sphecophaga to see if they can go undetected.
Sphecophaga females enter the wasp nest and lay their eggs on young just before they begin to pupate. The Sphecophaga larvae then feed on the wasp pupae killing them, he said.
The research is being funded by a Ministry for Primary Industries’ Sustainable Farming Fund (SFF) grant to the Vespula Biocontrol Action Group.
Both Brown and Groenteman are optimistic about the parasitic wasp, however, they said often multiple agents were needed to completely suppress a pest.
Brown has also been investigating the biocontrol potential of a mite, Pneumolaelaps niutirani, he found on wasp nests in 2011.