European and English Wasps
European Wasp and English Wasp appear extremely similar and are difficult to tell apart, but currently the former species is more common and widespread in the state. Both species have similar life cycles and behaviour. Vespid wasps are the most troublesome outdoor insect pest found around homes, in gardens, fruit orchards and especially where sweet foods, fruits or liquids are present. With their yellow and black stripes they are familiar to most Tasmanians.
However, European or English Wasps are sometimes confused with a native species Thynnus zonatus, or Flower Wasp. This species is found in coastal areas in Tasmania. It is longer and more slender than the vespid wasps and only the males are winged. These wasps do sting but are not attracted to meat like the introduced vespids and are a solitary species that do not form nests. Flower Wasps are not regarded as pests as they do not interfere with outdoor eating or attack fruit like the introduced wasps.
Vespid wasps are swift, strong fliers and are likely, particularly in autumn, to become aggressive when interfered with. When wasps are close by, you should avoid sharp movements because these will attract their attention and may excite them so that they sting. They are capable of inflicting a severe sting. Unlike a bee, each wasp can sting repeatedly.
The grubs are fed on insect and animal matter obtained by the workers. In this regard the wasps may be beneficial since they prey on many harmful insects, including flies and caterpillars. However their predatory activity, when intense, has been shown to severely diminish native insect fauna in some areas and has a detrimental effect on biodiversity.
Towards the end of summer the colony reaches its full size, and the workers forage for sweet materials much more than previously. Similarly their search for protein-based foods intensifies and often switches from insects to meat scraps,such as pet food or picnic food, to feed the rapidly increasing number of grubs. The wasps become more aggressive as their numbers increase and they are most troublesome during autumn.
Mating flights occur on fine, warm days in the autumn, after which the new queens seek over-wintering sites. The colony then declines and usually perishes, although in Tasmania some nests are maintained throughout the winter and are further enlarged in the following season.
Wasps attack a wide range of damaged, ripe fruit. In general they are unable to damage sound fruit and thus are rarely a problem in clean, commercial apple orchards. Sometimes the wasps will damage ripe grapes directly by entering the fruit where it joins the stalk. Thin-skinned fruits such as raspberries, peaches and apricots may also be subject to direct attack when they are ripe and particularly when they are overripe.
Occasionally wasps may be seen in large numbers about pine or gum trees. They are attracted to the sweet secretions of scale insects, aphids or plant exudates. Alternatively control the scale insects or aphids.
For information on registered chemicals and current off-label permits for European wasp, visit the APVMA website:www.apvma.gov.au Agricultural chemicals, including insecticides, are not to be used for any purpose or in any manner contrary to the label or APVMA permit unless authorised under appropriate legislation. Before using a chemical, read and adhere to the instructions for use on the label or APVMA permit.
IF YOU ARE UNSURE ABOUT DOING THE TREATMENT YOURSELF, IT IS BEST TO
OBTAIN THE SERVICES OF A LICENSED PEST CONTROLLER.
Tasmania Online | Service Tasmania
This page - http://www.dpipwe.tas.gov.au/inter.nsf/WebPages/CPAS-5Y9793?open - was last published on 9 November 2012 by the Department of Primary Industries, Parks, Water and Environment. Questions concerning its content can be sent to Internet Coordinator by using the feedback form, by mail to GPO Box 44, Hobart, Tasmania, Australia 7001, or by telephone.
Please read our disclaimer and copyright statements governing the information we provide on this site.
A text version of this page is also available.