Mosquito 101 — The bug biology you need to survive this season

‘Tis the season to be slappin’ — unless you get skeeter savvy with this advice from an entomologist

‘Tis the season to be slappin’ — unless you get skeeter savvy with this advice from an entomologist

(Credit: iStock/Getty Images)

It is a well-guarded intelligence that vampires are quite real. Sure, they don't wear capes, speak in syrupy, vaguely Romanian accents or coif their hair into obnoxious widow's peaks, but they really do vant to suck your blood. Taking to the skies to descend upon us and feast as the sun goes down, authentic vampires are just far more wee than the movies suggest. While their bites don't kill in this part of the world (usually, anyway) they do have the rare power to annoy us half to death.

Mosquito is spanish for "little fly" but the scientific family name for the common Canadian variety is Culicidae. Almost cute if it weren't for the blood lust, buzzing and itchy calling cards. Still, mosquitoes aren't singular in their thirst. Tons of animals practice hematophagy, or blood feeding: leeches, vampire bats, the gatefold butterfly — yup. Darwin even discovered vampire finches (full points to Hitchcock) on the Galapagos. But none of these last few live here. We'll have to satisfy ourselves with just the one winged hematophagous species in Canada — and one is more than enough.

Aside from being real-life nosferatu, mosquito anatomy alone is something of a horror show. Descriptions of the skeeter stinger, or proboscis (pronounced pro-bosses), read like a 19th-century surgical tool. For starters it has six parts: a sheath, two hyper-sharp serrated saw-like needles, two more to spread the meat flap a smidge post-incision and a fifth probe/syringe combo to mine our nutrient-rich veins. For more on their creepy, built-in apparatus peep this vid from PBS:

Face scrunching bug biology aside, they do represent real danger in certain subtropical parts of the globe and have garnered the honour of deadliest bite on the planet. Due to diseases like malaria, dengue and yellow fever carried and spread by some species, their annual death toll is actually in the hundreds of thousands. Those species aren't native to Canada and are rarely found here but global warming trends might well change that, in time.

Dr. Fiona Hunter, professor of entomology at Brock University and notable mosquito authority, has been studying the winged syringes for years. Back in 2017 she suggested there was at least some cause for alarm when Aedes aegypti, the species know to harbour both the Zika and West Nile virus, was found in southern Ontario. "I think it's alarming — for the country — that our climate is changing," confirmed Hunter. "In the last decade we've added another 10 mosquito species to our endemic list ... so we know something is going on." Happily, all the interloping mosquitoes found here have tested negative for Zika and West Nile virus and the government rates the threat as pretty low.

Still, it's easy to see how a sickness-carrying species could get out of hand. A little research reveals that a female mosquito has a significant clutch size (note: not a measure of her preferred tiny purse). A clutch is the number of eggs she can lay just 3 days after mating: it's an impressive 200 eggs or so. Likely, she'll do that three times should she live a full lifespan (about 48 days). I'll let you do the mosquito math there.

Fighting the good fight against something so prolific may prove more manageable for some. Thanks to a study that had a small sample of participants willing to become skeeter fodder, we do know mosquitoes are measurably more attracted to some folks based on genetic factors alone. Apparently, you're born into a legacy of lunchability. Case in point, another study suggests that mosquitoes are more attracted to humans with blood type O than any other blood group.    

But some experts, like retired U.S. Navy entomologist Joseph Conlon, reject even the most well-peddled theories about mosquito attraction. He maintains the blood type study was later debunked. He also says foods and colours matter little to mosquitoes. But he's adamant about one thing: "If you're a mammal, you're on the menu."

With all the duelling theories, we wanted to talk to someone who's been in the field. So, should you require more knowledge with which to arm yourself as this year's skeeter season gets underway, rest easy. We reached out to entomologist, natural science teacher and one-time resident skeeter expert at McGill University, Chris Cloutier MSc, who weighed in on the bloodsucking bane of the bucolic (and urban) BBQ.     

We've read that only females bite — why is that?

Females require a blood meal so that they can produce their eggs. They require proteins from blood in order to do so.

Gentle reminder that blood meal is crucial for her: 1 female = approximately 600 eggs a lifespan.

Are mosquitoes attracted to some people more than others?

Yes, they are. Recent findings suggest that the mix of bacteria found on the surface of the skin, or more specifically, the odours they produce are what make one person seem more attractive to skeeters than another. Although, one of the main attractants remains CO2 and those that maybe breathe a little heavier or possibly sweat more while walking for instance will produce more CO2. CO2 in your breath is a big factor.

Does the colour of what you're wearing really matter?

Yes. Navy blue, black and brown are the worst. Light colours like white, beige, yellow, are better for avoidance.

Is wearing perfume a bad idea (does it attract them)?

Not 100% sure, it has been noted that those who recently washed their hair or are wearing products like perfume are more attractive to them. Since they do work with an olfactory system (of sorts) and find their hosts via smell, anything you add to the mix might help or hinder. I guess depending on the product used, it could go either way.

Why are some years way worse than others for mosquito mayhem?

It all has to do with life cycles, which is greatly influenced by things like winter temperature, snowfall accumulation, spring rains, etc. Many of the real "biters" overwinter as eggs which were laid in depressions on the ground last fall. They hatch in response to flooding, so in years when rain is abundant or there was lots of snow cover, more puddles are formed and thus more eggs hatch. This is a simple answer, as other factors also factor in.

Is there a particularly bad time of day for becoming a buffet?

Dawn and dusk on average are worse, but there are species that bite at any time of day, especially in the shade.

Does anything really keep them at bay (might we rank effectiveness of smoke, bug spray, citronella, or those zapper lights)?

The only real effective repellents are those containing DEET or picaridin. All others have limited effectiveness, but for those people sensitive to chemicals, they are certainly better than nothing. Bug zappers are useless in most cases and simply kill other insects like moths and beetles.

Why do some bites get really big and itchy while others don't?

The reason they itch at all is the body's response to the saliva the females inject to improve blood flow and feastability. Some concoctions are different than others and thus the body reacts differently. Also, usually the worst bites occur in early spring as our bodies have gone a good 5-6 months potentially without a mosquito bite, so the immune system reacts strongly to the first couple bites each year.

Can you develop an allergy over time? Can you prevent one?

I have never heard of allergies to mosquito bites, but there are different levels of tolerance (if you will) to bites. Some people react very strongly and tend to swell more than others.

Are they truly the most deadly animal on the planet due to the death tolls of infectious diseases they spread?

This one comes up a lot. The mosquito is a vector of disease meaning it is simply the vehicle...the driver is really the pathogen (ex. Malaria, dengue, yellow fever, etc.) Those are what are responsible for human deaths. The mosquitoes just facilitate the transfer and proliferation. Place the blame where you may, but it is a team effort. I maintain that since they have a hand in it, they deserve the title as most deadly. Thankfully the number of species which are capable of spreading disease is actually quite low compared to the total number of species out there.

"It's not adapted to our winters," Cloutier adds, "thankfully." That said, with mosquito season poised to peak in the third week of June, maybe start dressing like a house painter. And mind the breathing.