You may have noticed.

High temperatures and sustained warm weather have led to an increased wasp population but understanding the sometimes aggressive little stingers can reduce the chance of being stung, experts say.

"If it is warm, they grow more quickly. If they can grow more quickly, they go through their generations more rapidly, you get more wasps being produced in a given nest and therefore you have more wasps out hunting about," Ken Fry told CBC News on Friday.

He's an animal science instructor at Olds College.

While there are 14 known species of yellow-jacket wasps in Western Canada, there aren't any hornets, which are much larger and come with more painful stings, Fry said.

"There's a group of wasps, Dolichovespula, that build their nests in trees, under the eaves. They are called aerial nesters because their nests are above ground. They typically prefer fresh food, they are actively hunting living caterpillars, beetle grubs, fly maggots, any insect of any sort. That's what they feed their young," he explained.

Ken Fry

Ken Fry, an animal science instructor at Olds College, says wasps are misunderstood and stings can be mitigated. (Submitted by Ken Fry)

Wasps differ from bees in terms of diet and aggression.

"Honey bees and bumblebees feed their young a combination of nectar and pollen, whereas the yellow jackets, they will feed their young meat, so captured insects," he said.

Fry says bumblebees generally are docile because they have smaller nests and therefore are less aggressive because "every worker they lose is a significant loss to that small nest size."

Wasps don't suffer from the same cautious approach to interacting with humans.

"Yellow jackets, having nests in the hundreds and potentially thousands of individuals, they don't have that much reluctance. Because they are naturally predators, they are more inclined to fight at a lesser level of provocation."

The contribution wasps make to the world around them, however, is largely misunderstood.

"For the most part they are helping to maintain a reasonable level of insect population in our ecosystems," Fry said.

"Without the predators we would be up to our ears in bugs. Our plants would be fully stripped because there would be no population control as it were. They do a great job of managing insects out in the wild and in our yards. It's just unfortunate that, in their hunting forays, they could encounter us."

Nicholas Holland

Nicholas Holland, owner of Peregrine General Pest Control Inc., says keeping a backyard free of food debris can reduce the number of wasps that come around. (James Young/CBC)

And it's those increased encounters that have a Calgary pest control company buzzing with business.

"Each of our technicians is taking care of at least 10 wasp nests a day," said Nicholas Holland, owner of Peregrine General Pest Control Inc.

"They are all over the place, from under front steps and back decks, to up in trees. It's crazy where they turn up but obviously they affect people trying to enjoy their properties and there is nothing worse than being stung by a wasp, especially unexpectedly."

Holland says there are steps people can take to mitigate wasp interactions.

"Don't leave the pop cans sitting outside, put them in recycling. Wash the recycling bin out. After you are finishing barbecuing, scrub the table next to it down. Remove the grease. Remove the things that are going to be attractive, that are sweet and juicy and appealing to wasps and other stinging insects," he said.

But if a wasp nest appears in a high traffic area, calling in a pro may be the best way to go, Holland said.

That's advice that Fry agrees with too.

"Don't try to antagonize the yellow jackets or don't, in a foolhardy way, try to get rid of a nest on your own."

Wasp killing

A dust is injected under a deck where a wasp nest has been located. The dust should kill the queen wasp within about 3 days. (James Young/CBC)

Fry says if you squish a wasp, a pheromone is released which is a battle cry for other wasps.

"If you squish a yellow jacket, guaranteed you are going to have a whole bunch of really angry sisters coming to check out the situation," he explained.

"It's best not to swat them."

The best home remedy, Fry says, is a two-litre pop bottle. Cut the top section off and place it inverted into the remaining portion of the bottle. Put the bottle a safe distance from doors or seating areas. A little sugar water is all you need to attract the wasps because they can get in but can't get out and they eventually drown.

wasp pop bottle trap

Ken Fry says the best way to reduce wasps is a pop bottle with sugar water placed a distance from doors or gathering areas. (Alison Zulyniak)

If you do get stung, baking soda can ease the pain around the sting, but if the reaction is more systemic it might take Benadryl or similar antihistamine.

Some people, like Fry himself, can experience anaphylactic shock if stung by enough wasps in a short period of time. It can require an epinephrine autoinjector like EpiPen or even hospitalization.

But for pest control expert Holland, avoiding wasps in the first place is the best medicine.

"Keep clear of a wasp nest for your own personal safety," Holland said.

"Being stung once is bad enough but having multiple stings can really ruin your day fast."


If a wasp nest appears in a high traffic area, calling a pro may be the best bet. (John P. Ashmore/Shutterstock)

With files from CBC's Diane Yanko, Allison Dempster and James Young