Why European Wasps are a problem

Mated queens come out of winter shelter in spring and start new nests on their own. Once the first workers emerge, numbers build quickly from around mid-December and peak in late summer and autumn. In autumn, new queens leave the nest to find somewhere to spend the winter. Exact timing varies with the weather each year.

Cold weather kills worker wasps, and mated queens shelter alone over winter. In Australia's milder climate, though, some nests survive the winter and keep growing. Over several seasons they can become very large nests of more than 100,000 wasps.

Traps can draw wasps away from a spot such as an outdoor table. Government-funded research found that trapping workers alone rarely reduces the overall population, because a nest can produce more wasps each day than traps catch. What reduces numbers is finding and destroying nests, backed by a well-placed trap program that is serviced through the season.

Protein baits work when worker wasps are carrying meat home to feed larvae. Government researchers link protein baiting to the mid-season build-up. In early spring there are few or no workers, and late in the season foragers mainly want sugar and won't take meat baits. In our experience, baits put out at the very start or end of the season mostly miss. Read why DIY wasp baits mostly fail early and late.

Queen trapping uses sugar-lure traps to catch queens as they come out of winter shelter in spring or leave the nest in autumn. It's well-meant, but in our experience queen trapping at the start and end of the season is mostly futile. The traps catch some queens, but not enough to change how many nests turn up, because the queens that aren't caught, and queens flying in from surrounding land, still start nests. It's a numbers game: one queen that's missed can produce thousands of workers and hundreds of new queens over several months. We put the effort into finding and destroying nests, and into a trap program timed for the mid-season build-up.

European Wasps are stout and about the size of a honey bee, bright yellow and black, with all-black antennae. They fly fast with their legs tucked in and rarely hover. Paper wasps are longer and thinner, with orange-brown antennae, and they often hover with their back legs dangling. See our Identification Kit.

Most nests are in the ground, often with only a small entrance hole showing. Others are in wall cavities, roof spaces, retaining walls, rockeries, tree stumps and conifer trees. Inside buildings, a steady stream of wasps going to and from one spot is a common sign.

Watch where the wasps fly. They may forage up to about half a kilometre from the nest and fly almost straight back to it, so the nest may be on a neighbour's land. Keep your distance, and don't poke, block or spray the entrance. Tell us what you are seeing and we will find it.

It isn't recommended. The ACT Government and Queanbeyan-Palerang Regional Council both warn against treating nests yourself because of the risk of stings. The ACT Government says nests on private land should be removed by a qualified pest control operator. European Wasps can sting more than once.

In the ACT, the ACT Government treats European Wasp nests on ACT Government land and takes reports through its online form or Access Canberra on 13 22 81. A nest on private land is the owner's responsibility. In Queanbeyan-Palerang, report nests on public property to the council, and use a pest controller for private property. Elsewhere in NSW, contact your local council about public land.

Use an ice pack to ease pain and swelling. Get medical help straight away if you are stung in the mouth, have difficulty breathing or develop an itchy rash. For life-threatening symptoms such as anaphylaxis, call 000.

In NSW, the European Wasp is established, so NSW DPI says sightings do not need to be reported to the department. In the ACT, you can report nests on ACT Government land to the ACT Government. We are always glad to hear about sightings through our report form.