Expert says warm September in Maritimes could cause higher aggression in bees and wasps

Maritimers have been enjoying high temperatures and beautiful weather this September, but experts on insects say there is a cost. They say the higher temperatures make wasps and hornets more territorial and aggressive.

Andrew Hebda is a retired curator of zoology at the Nova Scotia Museum. He says 10 degrees is an important temperature for wasps and hornets.

“Below that they are inactive and above that they are active,” Hebda said. “The warmer it gets the more active they are and the more they feed and they reproduce and the warmer it is the more generations we will have.”

Residents within the Maritimes may see more hives and nests around their homes. They tend to settle under eaves and overhangs. The pesky insects also find their way to restaurant patios.

Ann Simser is a lead server at Seven Bays Café. She says wasps and hornets are annoying for staff and customers.

“They come out here to sit and they go back inside because they can’t deal with them flying all around them,” said Simser.

Hebda said the insects are more aggressive when the food supply dwindles in the fall.

“I have definitely noticed the uptick in the last month, just like other pollinators they just want your food,” said Nova Scotia resident Matthew Wilson.

Ontario resident Chris Withnall said wasps and hornets have invaded Ottawa as well.

“I have been stung by bees, hornets and wasps, all of them,” Withnall said. “I’m one of the lucky ones, I don’t respond terribly but they do hurt.”

Unlike bees, wasps and hornets have smooth stingers that they can use multiple times. For those who are allergic, those stings can be life-threatening.

“What we are seeing is our response to a foreign substance and the venom being put in has some additional side effects such as pain or there may be enzymes,” said Hebda.

The effect of those stings can be cumulative, causing worse reactions with multiple stings over time, Hebda said.

“I guess stings get worse when you get older and I haven't been stung in like 20 years, so I imagine the next one is going to be terrible,” said Wilson.

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