Nova Scotia

Mosquitoes find you by your carbon dioxide say researchers

It’s been said many times: mosquitoes suck. But before they can suck your blood, they have to find you. And researchers are trying to better understand how they do that.

Once they have detected the CO2, the mosquitoes start looking for other signals a potential victim is nearby

Researchers found that once mosquitoes have detected CO2, they start looking for other signals a potential victim is nearby, like heat and moisture. (AP file photo)

It's been said many times: mosquitoes suck. But before they can suck your blood, they have to find you and researchers are trying to better understand how they do that.

A recent study indicates breathing out carbon dioxide (CO2) is what first puts you on the bugs' radar — not the smell of your shampoo, or the colour of your shirt, as some believe.

The experiment, undertaken by the University of Washington and the California Institute of Technology, put mosquitoes in a wind tunnel that had a spot painted on the floor.

At first, the mosquitoes did nothing, but once researchers introduced whiffs of CO2, the bugs honed in on it, then headed for the painted spot, thinking it might be a warm-blooded meal.

So it appears the CO2 heightened their other senses.

"Perhaps CO2 is a gate, something that creates a gating process," Andrew Hebda of the Nova Scotia Museum of Natural History told CBC Radio's Mainstreet.

Once they have detected the CO2, the mosquitoes start looking for other signals a potential victim is nearby, like heat and moisture.

Hebda says when heading out camping or fishing this summer, you can ignore the old wives' tales about not wearing scented cosmetics. In his estimation, perfumes and shampoos don't make that much of a difference.

But you should pay some attention to the colour you wear — not that mosquitoes care about how the colour looks.

"Colour, temperature, well essentially dark versus light, if you're dark in the day time, well of course you're attracting heat, and so that's strictly solar, you're a solar panel there," Hebda said.

No matter what you do, though, if you're breathing, the mosquitoes will figure out you're there.

Comments

To encourage thoughtful and respectful conversations, first and last names will appear with each submission to CBC/Radio-Canada's online communities (except in children and youth-oriented communities). Pseudonyms will no longer be permitted.

By submitting a comment, you accept that CBC has the right to reproduce and publish that comment in whole or in part, in any manner CBC chooses. Please note that CBC does not endorse the opinions expressed in comments. Comments on this story are moderated according to our Submission Guidelines. Comments are welcome while open. We reserve the right to close comments at any time.

now