If you've spent any time outdoors in Sampson County recently, you've probably had an unwelcome visitor buzzing around your head. Whether you're hiking through the woods, camping with family, working in the garden, fishing, walking the dog, or simply relaxing on the porch, deer flies can quickly turn an enjoyable day outside into an irritating experience.
Many people refer to these insects as "yellow flies" or "dog flies," but the insects that commonly harass us in Sampson County are actually deer flies. While true yellow flies belong to the same family of biting flies (Tabanidae), they are a different group of insects and have a different appearance. Deer flies are generally smaller than horse flies, have dark bands across their wings, and often display colorful, patterned eyes that are surprisingly beautiful, despite their painful bite.
Only the female deer fly bites. She requires a blood meal to produce eggs, while males feed on nectar and other plant sugars. Unfortunately for us, humans are just another suitable host. Deer flies locate their victims by detecting movement, body heat, carbon dioxide, and dark-colored objects. Once they find a target, they use scissor-like mouthparts to slice the skin and lap up the blood that pools in the wound. Unlike mosquitoes, they don't insert a needle-like mouthpart, which is why their bites are often immediately painful.
These flies are especially common around the edges of forests, ponds, swamps, streams, and other moist areas where their immature stages develop. In North Carolina, adults are most active from late spring through early fall, with populations often peaking during the hot summer months. Anyone who enjoys the outdoors in Sampson County has likely experienced one following them down a trail or circling relentlessly around their head.
Unfortunately, controlling deer flies is difficult. The immature stages develop in wetlands and saturated soils over large areas, making it impractical to treat breeding sites. Even if flies are eliminated on one property, new adults can fly in from surrounding habitats because they are strong fliers capable of traveling considerable distances.
Your best defense is personal protection. Wear light-colored clothing whenever possible, as dark colors tend to attract deer flies. Long sleeves, long pants, and hats provide additional protection. EPA-registered insect repellents containing DEET or picaridin can help reduce bites, although no repellent completely prevents attacks when fly populations are high. If you're spending extended time outdoors, a head net may provide the greatest relief.
Several traps are available that can reduce deer fly numbers in localized areas. Sticky adhesive patches attached to hats often capture flies that circle above your head before landing. Larger blue-and-black sticky traps and commercially available horse fly traps may also reduce populations around campsites, barns, and home landscapes, although they will not eliminate the problem entirely.
The good news is that deer fly season doesn't last forever. As temperatures cool this fall, their numbers will naturally decline. Until then, a little planning, protective clothing, and the right repellent can make outdoor activities much more enjoyable.
So, the next time you're enjoying a walk through the woods or relaxing by the pond and hear that familiar buzzing around your head, you'll know exactly who's paying you a visit. It isn't a "yellow fly" or a "dog fly." More than likely, it's a persistent female deer fly looking for her next meal.
