ACT residents should be on the lookout for European wasps as spring approaches, warn CSIRO Entomology and Canberra Urban Parks.

European wasps are an aggressive introduced insect now established in the Fyshwick area and spreading to other parts of Canberra. They can sting painfully, and some people suffer a dangerous allergic reaction.

European wasps are attracted to fruit, meat and sweet foods and drinks, which often brings them close to people. They are persistent and will attack and sting if provoked. "Unlike honeybees," says Mr Kim Pullen, Information and Advice Officer at CSIRO Entomology, "they can sting repeatedly. Outdoor living can be unpleasant when wasps are about."

The European wasp is slightly larger than a honey bee and has much brighter yellow markings on the body and yellow legs. Its black antennae are longer and thicker than a honey bee's.

Mr Pullen says European wasps are social insects which live communally in nests. "The only effective way of reducing their numbers is by destroying nests. This is a job, however, for experienced people only," he warns.

"The wasps will defend a nest aggressively, particularly early in the season. If you think you have found a nest, keep away from it and call a pest control company," says Mr Pullen. For those householders prepared to treat a nest themselves, CSIRO Entomology can provide information on the appropriate chemicals and methods.

The wasp has three castes: queen, male and worker. "The wasps we see are foraging workers, since the queen stays in the nest after establishing it. Males are only produced for a brief period at the end of summer," he says.

The nest itself is always concealed, usually underground and with the entrance hidden in vegetation, between rocks or in a tree stump. The wasps will also nest in wall cavities or roof spaces of buildings. Nests are constructed of a grey papery material, and are initially football-shaped. Larger ones become irregular and can be a metre long.

"A constant stream of wasps to and from a hidden spot is a certain indication that a nest is present," says Mr Pullen.

He says that food present at a picnic or barbecue will naturally attract European wasps in the vicinity. Covering the food will reduce the risk of being stung.

"It is important not to leave cans of drink open and unattended. A wasp may get into the can and sting the mouth or throat as it is swallowed with the drink. Drinking from a glass, or through a straw, reduces this risk," he says.

A wasp sting leaves a hot, red, swollen mark which can be very painful for a few hours. The pain can be reduced with an icepack or an anaesthetic pain-relieving spray.

"If you are stung in the mouth or throat, seek immediate medical attention because the swelling can cause breathing difficulties and possible choking," Mr Pullen warns.

The wasp is native to Europe and the Mediterranean region - its introduction to Australia was accidental. Since the first sightings in Tasmania in 1959, it has been steadily spreading and is now well established there and in Victoria and New South Wales. It may eventually occupy most of southern Australia.

CSIRO Entomology continues to liaise with state authorities in an effort to find effective ways to combat this pest.

Further information
Kim Pullen (02) 6246-4263 or 0419 428 400
Jenny Goldie (02) 6246 4194
(wasp photos available on request)