You may have noticed more wasps being a nuisance during outdoor dining these days.

That's because, according to Poulin's entomologist and director of technical operations Taz Stuart, it's the time of year when their natural food sources are starting to disappear.

"Aggressive is a good word," he says. "It's getting a little cooler at night, the sun's lower in the sky, and at the end of the day wasps (start) searching for... the sugars and the carbohydrates (from if), you know, you're making a steak or a burger or having a sweet pop or another drink; they're going to those food sources because their natural food sources are gone."

Stuart says wasps are social insects, and although they don't necessarily mark their territory, they may go tell their friends about the great food source they've found.

"And they'll track it down. They'll fly a great distance. If it smells good and the wind's the right way and a nest is nearby, you'll become their primary source."

If you're going to swat at them, Stuart says keep calm and collected, and move slowly. He also recommends checking your drink before you go for a sip.

"Always look into your can of pop or fold over the tab so they can't fly in. I've met a couple people who've, you know, drank a Coke on their deck and they got stung in the mouth because they didn't realize a wasp was inside the can."

Stuart says wasps will eat anything that's a food source.