Flies – Know Your Enemy

In America, Memorial Day is the traditional start of summer and now that that has passed, we are in it for real. If you spent time outdoors over the long weekend (and most Americans did), you undoubtedly encountered some flies. After all, according to this article, there are 17 million flies for each human being and there are nearly eight billion people on the planet (you do the math, it’s a lot). Not only are their sheer numbers staggering, the variety is as well – there are at least 120,000 species of flies. Since flies first appeared over 200 million years ago, this is an insect that has clearly excelled in evolution and adaption. All of this means that these fliers will definitely be out where you want to be this summer and shielding yourself from their annoying habits and the potential health risks they carry can be challenging. But, as with many things in life, knowledge is power and if you know what types of flies you are dealing with, developing a successful fly control program is within your reach.

House Fly (Musca domestica) -  

House Flies have big red eyes, translucent wings, and are grayish-brown with four large stripes running parallel down their bodies. 

By a large margin, the most common fly is the good ole House Fly. We are all very familiar with these irritating and disease-causing insects; they are a constant in all our lives. House Flies are known as “filth flies” because they feed and reproduce on rotting organic matter, manure and other smelly things. The majority of fly control methods out there work well against them (although none of them get rid of flies completely). These controls include parasitic wasps (ARBICO’s Fly Eliminators®),  smelly liquid traps, sticky traps, and sprays like Essentria IC-3. The downside is that there just so many of them that more keep coming (and humans and their pets keep making new messes for them). In one important way it’s to our advantage that their numbers are large – house flies are second in importance to bees as pollinators and are the primary pollinator for many plants. In the recent past, house flies have made their debut in Antarctica and their story there is yet another climate change cautionary tale (read about it here).With as many house flies as there are, we can be grateful that at least they don’t bite.

Stable Fly (Stomoxys calcitrans) – 

Stable flies have seven spots in a checkerboard pattern on their abdomen and long, needle-like mouthparts that project forward. 

Stable Flies are another filth-breeding fly species. However, unlike house flies that feed on decaying  and sugary organic matter, both male and female stable flies feed on blood. The image above shows a female stable fly engorged with blood. You can clearly see the long, straw-like proboscis she uses to suck up the blood. Stable flies do not generally feed on people (they are livestock lovers), but they will grab a human snack if their preferred hosts are unavailable. These flies are sometimes called Dog Flies because they’ll gather mercilessly around our beloved canines. Stable flies rest in vegetation, so they can be easily stirred up by lawn activities like mowing. This is a fly that can find you even if you live far away from any livestock. They have been known to travel more than 100 miles on their own and, occasionally large numbers of them are picked up by the wind and deposited great distances away in a sudden swarm for that area. Because they are filth flies, the same fly control methods used on house flies can be used on stable flies, but the success rate is not always as good as with house flies. The surest route to acceptable control would be to use the Fly Eliminators, sticky traps and sprays, and add a Bite Free™ Stable Fly Trap or a Biting Fly Trap.

Horse Fly (Tapadinae) – 

Horse Flies are short-bodied, but stout, and are brown, black or yellow. They usually have black splotches or patterns on their wings and stripes on their abdomens. These biting flies have protuberant mouth parts and very large, psychedelic eyes. This is a Greenhead Horse Fly, one of the largest species (can be over 1/2").

Horse flies, like stable flies, are biting flies that seek out mammalian blood. In the horse fly world, however, only the females drink blood (she needs a blood meal to form viable eggs); the males live on pollen and nectar for their short lives. Horse fly bites are especially nasty, as they don’t just break the skin – they cut into the skin with scalpel-like mouth parts, spit into the wound to keep it from coagulating, and feed as long as they can (here’s a video of a female feeding). The extravagant eyes of horse flies can help to distinguish between males and females; males have eyes that wrap-around while a female’s eyes are separated. Horse fly eyes are really beautiful, as are many eyes in the fly world. Check out this article for some truly stunning examples. Horse flies are another fly that can, and will, travel great distances for the blood they need. Don't discount their presence in your yard if there are no horses nearby, they do not need horses to survive and reproduce – just mammal blood. Horse flies are notoriously difficult to control, partly because they bred in watery natural habitats where larval control would be either illegal or unethical. Use everything in your arsenal to keep these suckers at bay - keep areas dried out when possible, use sticky traps generously, douse yourself and your animals in repellents and use traps specifically designed for horse flies  (Epps Biting Fly Trap® or the Biting Fly Trap). 

I have chosen to discuss these three flies as they are the ones that you will most likely come across and all have the potential to spread disease.  But, as shown in this image on the left, there are many more flies out there. Most of these flies are not a threat to you or your summer fun and will live out their lives in a few days. I encourage you to take a little time to know and appreciate the benign ones and to protect yourself from the potentially dangerous ones. I also encourage you to check out our full line of earth-friendly fly control.

Keep the fly swatter handy this summer!

Submitted by Pam