Sunday, 4 February 2007

European wasps

In the late afternoon, European wasps (Vespula germanica) arrive in my garden. They're after wood, which they strip from the fence posts and chew into pulp. Somewhere, in this rapidly gentrifying area, a wasp colony is building an extension to its nest and the materials are coming from my garden.

Two species of introduced Vespula are found in Melbourne. The European wasp is the more abundant, whereas the English wasp (V. vulgaris) is restricted to the eastern suburbs. The two are easy to tell apart—if you can get close enough without provoking them. The European wasp has a black arrowhead on its first abdominal segment. The corresponding mark on the English wasp is a small triangle. (You can see that in this image from this CSIRO insect site.)

European wasps are recent arrivals in Australia. They became established in Tasmania in the late 1950s / early 1960s. Within two decades, they were recorded on the mainland. At almost the same time, the English wasp also appeared in Victoria. This species went in the other direction, spreading to Tasmania, where it has been very successful. Museum Victoria has lots more information on these wasps in Australia.

I took this picture with my digital camera set to telephoto. The flash seemed to upset the wasp, so after firing off half a dozen photos I backed away in a nonchalant yet determined way. Although I don't have a serious response to the toxin, I've been stung enough times to know that any encounter between me and a shirty insect is bound to end badly. And not for the wasp.


Duncan said...

I've been wondering if the fires in the high country have had any effect on the large populations of European Wasp up there. A chap I know was set upon in the Moroka area and suffered a large number of stings, quite life threatening.

Snail said...

It'd be good if the fires did burn out the nests. But I suspect that the buggers would just recolonise.

I can't believe how abundant they are in some areas. Having lunch in a cafe in the Dandenongs once, I was driven indoors by the swarm of wasps. They were like a black and yellow blizzard.