Scientists want to introduce wasp
An Australian beetle chews its way through millions of dollars in forestry profits every year but scientists say introducing a tiny wasp could change that.
Scion, the Crown Research Institute focused on the forestry industry, has applied to release a parasitoid wasp to control the eucalyptus tortoise beetle.
The Environmental Protection Authority is considering the application to introduce the Eadya daenerys wasp, which could help control the beetle by laying eggs in its larvae.
The wasp larva would then eat the inside out of its host, emerging from the beetle larva as it reached maturity, leaving just a skin behind.
Unlike parasites, which do not kill their hosts, parasitoids always do, and introducing the wasp could deliver a serious sting to beetle survival rates.
The authority’s general manager of hazardous substances and new organisms, Dr Fiona Thomson-carter, said about 90 per cent of tortoise beetle larvae survive into adulthood but if a larva is attacked just once by the parasitoid wasp, survival drops to just 10 per cent.
Although tortoise beetle larvae stood little chance against the wasp, it could only sting soft tissue and was harmless to humans.
Thomson-carter said the tortoise beetle caused significant damage to susceptible species of eucalypts.
Scion estimated that the beetle cost the forest industry between $1 million and $2.6m a year in chemical control costs.
Effective biocontrol could prevent $7.2m in annual losses caused by impaired tree growth and yield caused by the beetle.
Farm foresters and owners of smaller plantations could not afford aerial spraying to combat the tortoise beetle, so biocontrol was their only realistic option.