A nest weighing almost 100 kilograms (220 lbs), without wasps, has been unearthed in Tasmania, and appears to be the largest wasp construction ever found. The discovery marks the end of a season in which much of Australia has been overrun, or perhaps overflown, by the invasive creatures.
It is often said that Australia is trying to kill you. Between the venomous snakes, deadly spiders, sharks, crocodiles and jellyfish, it can indeed seem like that, but the animal that causes the most grief to residents isn't even a native species. European wasps arrived in southeastern Australia in 1959 by way of New Zealand, and multiplied to plague proportions from a lack of natural predators.
The European wasps (Vespula germanica) don't kill many people, but then again, neither do Australia's local species. However, being common in the places where most Australians live, they've haunted many a barbeque and picnic.
Few people have had it as bad as the Waddington family of Karoola. According to Simon Fearn of Launceston's Queen Victoria Museum, “The people had been experiencing lots of wasps right from early spring. I suspected there must have been a second year nest on the property. We tried to find it but were not successful simply because there were so many wasps flying around it was hard to find.” However, the offer of $20 if he could find the nest was all the incentive 12-year-old Jordan Waddington needed.
Getting rid of the wasps, removing the overgrowth and dirt and digging the nest out required several days' work, and Fearn said he got stung several times, despite inserting toxic chemicals in the evening. “If you tried to do that during the day, you'd probably be killed.” Still, he thinks this wasn't too bad, “considering that a nest like this could contain more than 100,000 wasps.”
The one cubic meter (30 cubic feet) nest is now on display at the museum.
Fearn says the nest is so huge because it was into its second year of growth. V. germanica produce nests the size of a football before the majority of the species die off over winter. “The nests are effectively made of paper, so if they get wet they can become moldy,” Fearn says. The queens hibernate before establishing a new nest in the spring. However, when the winter is mild and dry enough, the nest inhabitants can survive and keep building the following year.
Besides their annoyance effect, the wasps can be damaging for local farmers. “All the workers at this time of year are frantically trying to get sweet, sugary substances,” says Fearn. “Any fruit crops, apples, pears, grapes they will go after. I've seen ripe pears that European wasps have just completely hollowed out you just have the skin hanging on the tree.”
The effect on local insects is less well known, but Fearn thinks the “wasps must be eating more [native insects] than all the local birds put together.”
