What’s with all the mosquitoes? B.C. expert says late summer to blame

As the summer temperatures rise, more and more mosquitoes are making for a buzzing annoyance on the Lower Mainland.

There are a number of different types of mosquitoes in B.C., according to Carl Lowenberger, a professor of Entomology and Parasitology at SFU. However, what you’re likely swatting away right now is what he refers to as a snowmelt species.

“These are mosquitoes that do not lay their eggs on water or in the water, but they lay their eggs on the borders of water, above the waterline. They do this along tributaries of the Fraser River or in depressions where snow will fall and snow will melt,” Lowenberger explained.

“What happens is that these eggs can remain viable for many years. So if we don’t get a good rainfall, don’t get a good snowmelt, the eggs which were laid two years ago will just sit there for another year, two or three or four years. Eventually, we’ll get a year like we have this year with a high snowpack, a lot of rain, and they all get inundated. So they all get flooded and all the eggs hatch at the same time.”

But there’s also the fact that this spring was much cooler and wetter than usual. Lowenberger says larvae that hatched during that time would have taken longer to develop into mature mosquitoes as they waited for warmer temperatures to set in.

“Rather than come out over a few weeks of emergence, they’re all coming out in a much shorter period of time and they’re all looking for a food source,” he told CityNews, noting for female mosquitoes, humans and other animals are that food source.

But what exactly attracts mosquitoes? Are there specific factors that make a person more likely to get bit?

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Lowenberger says the research is ongoing.

“The data and the conclusions are not conclusive, but basically, if you’re hiking somewhere or walking in the woods, mosquitoes will notice your movement and be attracted to a moving object. As you get closer, they’ll realize it’s giving off a heat signal so they can detect the fact that you have a heat signal of a certain temperatures. As they get closer, they’ll cue in on specific smells on your body — mainly sweat and carbon dioxide — and some studies suggest it depends on the bacteria on your skin or some other odours,” he explained.

If you want to avoid getting bit, Lowenberger suggests wearing long sleeve shirts and long pants, though with the heat that may be the last thing you want to do. He says insect repellents are another option, as are other products.