What might happen if humans eliminated mosquitoes?

Mosquito mycteria/Shutterstock.com

Nothing signals the start of summer quite like the sound of the bug zapper, the smell of citronella candles, and the joy of sharing insect repellent.

But much more than just an itchy nuisance, mosquitoes are considered the deadliest animal in the world. They carry disease that results in the deaths of one million people worldwide every year—and Canada is no exception. While Florida launched aerial-spraying programs this spring to stop the spread of the Zika virus, there’s similar concern north of the border, where they’re known to transmit West Nile virus.

Given just how dangerous and annoying the pests are, it makes you wonder—wouldn’t we just be better off without them? After all, what would happen if mosquitoes faced mass extinction?

According to Kateryn Rochon, an entomologist at the University of Manitoba, the answer is not much. Mosquitoes are a valuable part of the food chain—particularly in aquatic environments, where they’re consumed as larvae by fish and frogs—but the ecosystem would bounce back in the long-run if they were to go extinct.

“As far as I know, there is nothing that could be considered ‘mosquito-dependent,’” says Rochon. If mozzies were eliminated, another insect would simply rise up to take their place as both a food source and pollinator in different ecosystems. (That’s not to say that the replacement insect would be any more tolerable; it might also carry disease and a nasty bite.)

But before you start cheering for the complete annihilation of mosquitos, hold your applause—it’s not going to happen any time soon.

“We’re not going to eradicate mosquitoes in Canada, so it’s a moot point,” says Rochon. “Nobody is working on eradicating all mosquitoes.”

With around 80 species of mosquitoes in Canada—60 of which bite humans—mass extinction isn’t on any scientist’s agenda. Despite sensational news reports that indicate otherwise, research is focused on specific species, usually invasive, which are vectors of human pathogens. For example, Aedes aegypti, carries dengue virus, zika virus, chikungunya virus, and yellow fever virus. Originating in Africa, it’s invasive everywhere else, making it a target for elimination. Another species, Anopheles gambiae, carries malaria, which is why scientists are genetically engineering mosquitoes that produce only male offspring, in order to prevent the transmission of disease. (Only female mosquitoes bite.)

That’s not to say that controlling mosquitoes isn’t possible. In fact, it’s likely already happening in your city.

“When people think ‘mosquito control,’ they think of big trucks with foggers and stinky chemicals in the air,” says Rochon. This is misleading—instead, stagnant water is treated with a biocontrol agent to effectively kill mosquito larvae. (It’s harmless to other insects and animals.)

So the next time you spot a municipal worker in a ditch with a back-sprayer, stop to say thank you. Chances are, they’re not spraying for weeds—they’re actually getting rid of your least-favourite insect.