Worker wasps are 12-15mm long (about the size of a Honeybee), bright yellow (not orange) with black markings including arrow-shaped marks down the middle of the abdomen with paired black spots on the sides. Wings are long and transparent, antennae black and legs mostly yellow. Queens, usually only seen in winter and spring, are similar but larger (20mm). Nest is nearly always concealed, commonly underground or in a roof or wall cavity.
Tasmania and wetter parts of South Australia, Victoria, the ACT and south-eastern New South Wales. Mostly found in suburban areas and farmland. Accidentally introduced to Australia; native to Europe and temperate Asia.
A social wasp, forming large colonies. Queen spends winter hibernating under shelter and emerges in spring to establish a new nest. Her first offspring are workers which take over nest chores. A "paper" nest is made by mixing saliva with wood fibres and grows over summer to reach the size of a football.
Workers feed on sweet substances such as secretions from sucking insects, fermenting fruit and people's food and drinks. They feed their grubs in the nest with other insects and spiders which they catch and kill, or with bits of meat from carrion or pet food bowls. The nest population may be several thousand by the end of summer. A colony produces and releases new mated queens in autumn then dies out in winter. Occasional nests survive winter and continue to grow.
Serious pest. Wasps will aggressively defend their nest by swarming out to attack a disturbance. Sting is painful and multiple stings or a sting in the throat can be dangerous or fatal.
Also an environmental pest: high numbers of wasps can denude an area of other insects and spiders. May have some beneficial value as predator of pest insects.
!Warning! Do not approach an active nest. Call a pest control operator to destroy nest.
Be aware of wasp hazard at barbecues and picnics. Cover food and drinks. Do not drink directly out of cans or bottles. Wasps can get on food and into drink bottles and cans outdoors, where they can be accidentally swallowed.
For multiple stings or stings on the throat, seek urgent medical aid. Otherwise apply ice pack to site of sting or anaesthetic spray. Or follow some advice from 400 years ago: "If any venomous beast, by his sting or biting have caused your flesh to rise... put upon the stung place the dung of a cow or ox, very hot."