Why Is It So Hard to Swat a Fly?

Frustrated man holding a fly swatter

Ever wonder: why is it so hard to swat a fly? It is already annoying to have your day disrupted by a pesky house fly suddenly whizzing by, hovering around your space, and often trying to fly right into your face! Even worse, when you try to smack the little nuisance with a fly swatter, it avoids your every advance and hovers just a few inches away without breaking eye contact, like it’s taunting you.

We’re here to tell you that flies do not have the emotional capacity or advanced sentience to playfully annoy you on purpose (at least, as far as entomologists know). Instead, flies simply possess the anatomical features and instincts to avoid your attacks with perfect precision. To learn more about why flies are so difficult to swat—and our experts’ tips for beating them at their own game—just keep reading!

Why Is It So Hard to Swat a Fly?

Flying and Take-Off Speed

As we’ve explained about gnats, all “true flies” (like the common house fly) belong to the taxonomic order Diptera. Any flies in this group are the ones that aptly anticipate your every swat due to their halteres. Halteres are teensy, knobby organs that modify the hind wings of all flies to serve two functions:

  1. Halteres help flies balance their position and stabilize themselves mid-flight.
  2. Entomologists have recently discovered that the halteres of the suborder Calyptratae (which includes the common house fly) vibrate mid-walk to help them launch into flight with only one beat of their wings in a mere seven milliseconds—that’s one-fifth of the time it takes other types of flies to take off!

Ultimately, even if you’re known for your incredible reaction speed, you don’t stand a chance against a bug that can fly away faster than you can blink; we mean that quite literally—a human blink occurs within about 100-400 milliseconds!

Mid-Flight Maneuvering

True flies’ halteres not only help them launch into the air at incredible speeds but also improve their mid-flight positioning capabilities, helping them quickly rotate their bodies up to 90 degrees, dramatically changing the flight course in seconds! That is why a fly can zip around you in all directions and suddenly have you turned around, clueless as to where they went!

Unmatched Sense of Sight

Flies have two compound eyes, giving them incredible vision. Their eyes do not move like ours, but they don’t need them to; a fly’s field of vision is nearly 360 degrees thanks to the thousands of tiny eyes (or lenses) within their two prominent eyes. Also, a fly’s brain processes images at about seven times the speed of a human’s, so flies see your fastest movements in slo-mo. 

How to Swat a Fly

Now, you know the answer to the question: Why is it so hard to swat a fly? In summary, flies have multiple advantages that make them quicker than you.

Still, we have some advice on swatting flies successfully, but you need to forget trying to be “faster.” Instead, consider your advantage over a fly, which is the ability to strategize with logic, anticipating your opponent’s next move. Though it seems flies know when you will swat them, they don’t; they simply move as soon as you do.

With these facts in mind, you need to wave in the direction of the standing fly so it takes off into the air, guess where it will land, and smack it immediately when it presumes it lands safely. We know it is easier said than done, but it is the only way to take care of a single fly without luring it into a sticky trap. 

When You Have a Major Fly Problem

Today, we’ve taught you how to take care of one pesky fly, but remember that swatters or DIY and store-bought fly traps will not cut it when an infestation swarms your property. If fly swatting becomes a part of your routine multiple times a day, you need a professional to investigate, and our experts would be glad to take care of your fly problems for you!

At Vulcan Termite and Pest Control, we have proudly served families in Alabama since 1965, and we would love to help yours, too! Call us at 205-663-4200 or contact us online today to learn more about our affordable, effective pest control solutions.

To learn more about pests in Alabama and how to prevent them, check out our pest blog!