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Get set for a likely re-run of last summer’s al fresco fiasco

A King Valley winemaker says he is already planning for a new season of European wasps, the aggressive pest that swarmed Melbourne in high numbers last summer, dashing hopes of would-be outdoor diners across the region.

Words by Kate Stanton
 
A surge in wasp numbers last summer tested the patience of diners.

A surge in wasp numbers last summer tested the patience of diners.

“Last year was horrendous,” says Fred Pizzini, owner of Pizzini Wines. “We eradicated about 40 nests within six or seven hundred metres of our cellar door.” 

Mr Pizzini says he will try to cull this year’s crop of wasps with homemade traps using fermented honey water.

“When we had functions, people were blaming us,” he says. “It’s not the fault of the venues. It is just a consequence of the conditions.”

“At the moment, the wasp queens are currently waking up from hibernation and they will start looking for sites to found new nests.” — Patrick Honan, Museum Victoria entomologist

Museum Victoria entomologist Patrick Honan says last summer’s wasp population hit a 20-year high, with wasp numbers reaching plague proportions across Victoria.  

“Enough to get people’s attention,” Mr Honan says. 

Tim Avenell, who works at a call centre for pest control company Rentokill, says last summer was an “unusually freakish season” for wasps. 

“Every call was about wasps. You’d finish one call, there’d be another call,” he says. “It was all over metro Melbourne.” 

Mr Honan says is still too early to tell whether the trend will continue. 

“At the moment, the wasp queens are currently waking up from hibernation and they will start looking for sites to found new nests,” he says.

In Europe, where the wasps originated, winters are cold enough to kill most of the nests. But in Australia, where winters are warmer, 10 per cent of the nests usually survive. 

Melbourne just had its coldest winter in 26 years, though it may not have been wet enough to drown the nests, which can hold up to 100,000 wasps. 

“If we get a lot of spring rains those new nests will be drowned,” says Mr Honan. “We’re not going to know until mid-to-late summer, because that’s when the nests get big enough to make an impact on people.” 

European wasps love fruit and meat, which means they are particularly prone to spoiling barbecues and picnics. 

Bees sting only once. But European wasps can sting repeatedly. Last March, a Wangaratta woman was stung 30 times when she knocked on someone’s front door, disturbing a neighboring nest.  

David Gay, of the Australian Environmental Pest Managers Association, says he has a “gut feeling” the wasps will be back.  There were just too many last summer. 

“You’d never get them all,” he says. “Given the larger base number, we’d expect that there would be a bigger starting number.”

“It was pretty disastrous. I think a lot of people probably didn’t come back while [the wasps] were here.” — Paul Van Der Sluys, of the Fairfield Boathouse and Tea Gardens

Mr Gay also has a theory that the popularity of urban beekeeping has made people hesitant to disturb nests. 

“Bees are sexy at the moment,” he says. “Some people have got wasps but think they’re bees and let them go.” 

Paul Van Der Sluys, who runs the Fairfield Boathouse and Tea Gardens, says lingering wasps can have a huge financial effect on his business. 

“It was pretty disastrous,” he says of last summer’s plague, which lingered and actually hit hardest in March and April.  “I think a lot of people probably didn’t come back while [the wasps] were here.”

Mr Van Der Sluys says the insects were particularly attracted to his food. 

“They were eating the chicken,” he says. “They love sugar as well, so they were eating all the jam on their scones.”

Mr Van Der Sluys says he usually tries to find and destroy wasp nests himself. But he thinks councils should be more “proactive” about helping businesses during wasp season. 

“You ring the council and they say ring a pest exterminator,” he says. “There should be someone walking around looking for these nests.”

Mr Van Der Sluys leases his business from Yarra Council and the surrounding area is on council land.

Councils around the city tell people who find wasp nests on private property to call an exterminator. 

But it’s hard to determine who is responsible when wasps fly everywhere. At what point do they become too big a problem?

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“It’s the same question with every pest,” says Mr Honan. “Should the government be controlling rats and mice in your home? Should the government be working on some sort of pest control for your plants?”

Latrobe MP Jason Wood last March called for the government to spend $1.5 million to find a biological way to kill European wasps.

But Museum Victoria’s Patrick Honan says he and other scientists tried and failed 20 years ago to come up with a successful wasp-killer. He says the best way to get rid of wasps is to track down the nests one by one. 

“They’ll always be here,” Mr Honan says. “And their population will always vary from year to year. And we’ll always need to manage them in some way.”

Mr Gay, of the pest managers association, says people who find wasp nests on their property should immediately call an experienced pest control professional. But for the brave at heart, Bunnings sells “Wasp Killer and Nest Destroyer” for $14.07. 

► An edited version of this story was also published in The Sunday Age

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