Mosquitoes are back. Here's what to expect
After a delayed start due to cool spring weather, Ottawa's mosquito season is ramping up as temperatures warm. Experts say the city is in for a typical heavy season.
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Mosquitoes are emerging across Ottawa as warmer temperatures finally arrive after a cool, damp spring that delayed the typical breeding cycle.
Marc Avramov, a PhD candidate in Carleton University's biology department, says the cooler spring slowed mosquito development — nights dipped below 7 C even as days warmed, which kept the bugs lethargic. But that reprieve is ending. "When it's really warm during the day, but then it drops down quite a bit at night, what happens is the developmental process for the mosquitoes slows down and we don't see this typical explosion of activity," Avramov said. "However, I've started to notice more mosquitoes buzzing around and biting pretty heavily in the past few days."
Robert Anderson, a research scientist at the Canadian Museum of Nature, explains the mechanics. Mosquitoes thrive in standing water left by melting snow. Eggs laid around pond edges hatch when temperatures rise, producing larvae that feed in the water before emerging as adults. Environment Canada is forecasting high-20s C daytime temperatures and lows around 15 C — ideal conditions for the cycle to accelerate.
Avramov notes Canada faces mosquitoes year-round regardless of conditions. "We're always going to have a pretty solid amount of mosquitoes." The city has roughly 40 of Canada's 80-plus mosquito species.
The season is hitting its stride just as patios and pools reopen.