|European wasp queens are about 20mm long, approaching twice the size of the worker wasps which are 13 - 15mm
long, about the same size as a honey bee. Wasps have shiny black and yellow stripes with black spots on the abdomen and are not obviously hairy like the honey bee which is markedly
hairy and has yellow and brown bands on the abdomen. The wings of the wasp are folded when at rest. The legs of the wasp are mainly yellow while the legs of the honeybee are
The entrance to a European wasp nest site is generally via a hole in the ground with workers flying in and out on foraging activities. The nets, which are normally hidden
underground but sometimes found in wall and roof cavities of buildings, are made of grey-coloured 'wasp paper' and may grow to the size of a basketball or more by the end of the season
(see photo below).
Native paper wasps (Polistes) are brown in colour without pronounced stripes and building round, exposed combs suspended from the branches of shrubs and also eaves and gutters of
buildings. Mud dauber and potter wasps have black, brown and yellow markings and many have long, thin waists. They build cells from mud which are often attached to the walls of
houses. The larvae in the cells are provided with paralysed prey such as caterpillars or spiders.
Because of the benign weather which results in a much longer 'wasp season' and an abundance of food including native insects and human food sources, and possibly because the wasp was
introduced with none of its natural enemies, this species has thrived in Australia. Their nests are typically twice the size and can produce more than 8,000 new queens per colony
compared with less than 2,000 queens from a European colony.
Significantly, this species can over-winter in Australia, resulting in nests of prodigious size in following years (See photo below). Thus, their potential for population increase and
geographical dispersion are far greater than in their original homeland.
|Below: Large European wasp nest (Tasmania)
Above: European wasp killing honey bee
This aggressive colonizer now threatens rural industries such as berry and grape growing and beekeeping and has the potential to impact adversely on tourism when they are very abundant
at outdoor venues.
Because of high densities and their insect-foraging activities, European wasps can destroy virtually all insect species in an area with up to 100kg of insect and spider prey per year
captured by foragers for a single over-wintering nest.
This heavy insect predation pressure results in a decrease in biodiversity through loss of birds and other predators which feed on insects. There is also a potential for a
decrease in plant pollinating insects with potentially disastrous consequences for native plants.
What to do to find, target and destroy nests
The destruction of their nests is the only effective way to reduce the impact of the European wasp in the community. If there are wasps in your area, try and locate the nest
entrance, talk with your neighbours and raise awareness of the wasp problem. After collecting food or wood fibres for building, worker wasps generally return directly to their nest -
try and follow the 'wasp line' and establish the direction back to the nest.
Once found and confirmed by phoning the European Wasp Hotline on phone 02 6162 1914, wasp nests are best destroyed by a professional pest controller. If you attempt to destroy a
nest without suitable experience and protective clothing, be warned - European wasp nests in Australia can be twice as big, with may times more worker wasps, than their counterparts in
European wasp building paper nest
The European Wasp Seasonal Cycle in the ACT
Winter (June - August) - Queens in hibernation. A few over-wintering nest still active.
Spring (October) - Queens leave their hibernation quarters and search for suitable nest sites and establish embryonic nests.
Early Summer (December) - Nests with several hundred cells and hundreds of worker wasps. Foraging and building activities increasing.
Summer (January - February) - Nests increasing in size with up to 10,000 rearing cells for worker production. Up to 1,000 adult worker wasps per nest.
Early Autumn (Late March) - Queen cell building begins. Up to 2,000 adult workers present.
Autumn (mid to late April) - New queen adults start being produced. Number of worker wasps can reach 3,000 per nest.
Late Autumn (May) - Queen production in full swing. The number of adult wasps up to 4,000 per nest. colony cycle reaches its climax with up to 30,000 worker-rearing cells
and 15,000 queen-rearing cells per nest.
Winter (June - August) - After producing upwards of 7,000 queens, some nests continue into winter mode and low-level queen production is maintained. A maximum of 12 -
16,000 queens can be reared in a single nest. Most queens leave their nest, mate and then hibernate until spring. Very few nests successfully over-winter.
For identification of the European wasp and other insect and spider specimens, and for further information, contact:
|European Wasp and Insect Identification Hotline
Reproduced with permission.