Fly Season In Montreal Is Upon Us — Here's How To Keep The Juicy Buzzing Menaces At Bay

There are several types of obnoxious fly out there.

Staff Writer
A fly trap in an outdoor greenhouse has caught several species of fly.

A fly trap in an outdoor greenhouse has caught several species of fly.

"About mid-afternoon, the black fly arrives.

"His trick is to alight on your neck, run up to your cap or behind your ear, and suck till full. [...]

"On the bad days, [...] a man is submerged in a ferment of flying, alighting, crawling, biting, bleeding bugs; and it is too much. The citronella-castor fails; head nets stifle you; life darkens and – but with dusk, they are gone."

The year is 1922. Travelogue author T. Morris Longstreth is making his way across the Laurentian woods, which are swarming with many flies, including the menace Montrealers know all too well: the black fly. Known to invade houses in the hotter months of the year, black flies and their close relatives are a torment and a scourge. Here's what you need to know about them as their season comes ever closer.

What are those flies that swarm my house in the summer?

They're most likely either the black flies that have tormented us since long before 1922, or they're a similar fly called the cluster fly.

Black flies emerge when temperatures increase, usually beginning around May and especially June. They're mostly harmless, but the females can bite and draw blood.

Cluster flies are similar in size to black flies but have a greyish, silvery body. They're named for their penchant for gathering in clusters in houses in the warmer months, and they're not dangerous besides being a nuisance.

Are black flies or cluster flies dangerous?

According to Health Canada, neither type of fly causes extreme harm. Cluster flies especially are not typically hazardous, but they're certainly bothersome.

How do you get rid of flies from your house?

The best way to get rid of cluster flies is by killing them, either with a fly swatter or using commercial fly traps, according to Health Canada. Cluster flies don't breed inside, so killing them all is the best way to end your infestation.

Pesticides are an option for when your infestation is quite severe. Be aware that killing cluster flies makes them release a gross smell, and they can even stain surfaces if they're smashed. Gross!

Black flies operate similarly, so killing them by physical or chemical means is the best way to go.

To prevent fly infestations from happening in the first place, Health Canada recommends keeping your window and door screens properly fitted, weather-stripping windows and doors, and filling any crevices around openings in your building's structure. Basically, if you make sure they can't get in, you'll never have to get them back out again.

Access to food, which in the fly's case mostly means sugar, is one key way flies survive inside for longer than a few days, according to the University of Florida. Making sure your kitchen areas are clear of food residue and potential fly food is a good way to ensure a minimal amount of flies this summer.

This article's cover image was used for illustrative purposes only.

Willa Holt
Staff Writer
Willa Holt is a Staff Writer for MTL Blog, often found covering weird and wonderful real estate and local politics from her home base in Montreal.