Although they scare me more than stinging insects, I’ve never actually been bitten by a horsefly. In fact, the longest interaction I’ve ever had with one of these scary dipterans was at summer camp when a friend of mine rescued a big, gray horsefly from drowning in the pool. She, her twin sister and I spent a good portion of that week rescuing bugs from water and footpaths, as this girl was superhumanly adept at handling bugs and would scoop up stinging and biting insects like they were caterpillars.
We carried (or she carried and we followed) the partially-drowned horsefly over to a counselor to ask if the big fella was okay. The counselor, apparently unaware of my friend’s superpowers, snatched the horsefly out of her hand and chucked it over the pool fence in one fluid, reactionary motion. We stood there gaping for a few moments while the counselor processed the situation and tried to convince us that the poor dipteran was okay. However, its fate remains a mystery to this day – as does where all the camp friends I made over the years have gone off to. Hope they’re all doing well.
Anyway: horseflies. These blood-sucking insects really are flies in the order Diptera and get their name from feeding on horses. That’s right, for once the taxonomists actually gave an arthropod a logical name. Give yourselves a pat on the back, guys, good job. I knew you could do it.
Horseflies are so despised that they make mosquitoes look good. I mean, no one wants to have their blood sucked, but in North America mosquito bites just itch while horsefly bites are painful from the get-go. Then again, mosquitoes are infamous for spreading malaria, Zika virus, West Nile virus and other deadly diseases in other parts of the world, while at most a horsefly will give you a small, potentially infected welt… There’s really no winning when it comes to vampiric dipterans.
Here’s a little nightmare fuel for ya: you cannot escape horseflies. Want to go swimming this summer? Horseflies are attracted to water. Rather go for a bike ride instead? Hopefully it’s a rusty bike, because horseflies like shiny things. Guess you’ll just take your dog for a walk then, huh? Well horseflies are also attracted to movement. Fine then, you’ll just sit there and do nothing! Wrong – horseflies can detect carbon dioxide, so unless you plan to hold your breath until September, they’re coming for ya. But you can fight back against the horseflies, right? Sure, but be prepared to go to war, because horseflies are hardy insects that will pursue their quarry until they’re full or dead.
I can’t believe I’m describing a fly and not some sort of horror movie monster.
As annoying and terrifying as they may be, horseflies aren’t all bad. As proven by mosquitoes feeding bats, frogs, and dragonflies, even the most obnoxious arthropods still serve a purpose. On one hand, horseflies are pests that drain the blood of people and livestock, and are known to spread disease. On the other hand, they’re pollinators and a source of nutrition for birds. You can be the judge of whether the pros outweigh the cons, but never let it be said that horseflies are solely a nuisance.
Just as I’d rather live in a world with mosquitoes than a world without dragonflies, think of it this way: a few pesky horseflies means a few more birdsongs this summer.