If you live near or frequent wooded areas, chances are good you have experienced deer flies in 2019. The wet weather this spring and early summer set us up well for a season of deer flies.
Deer flies are known for their painful bite, delivered by the female as she collects a blood meal necessary to produce eggs. It is estimated there are some 30 species of deer flies native to Indiana. Deer flies are approximately one-half inch long, black with some gold coloring, and a wing design that might remind you of a modern jet fighter.
Much like a jet fighter, they are equipped with all kinds of sensors. Deer flies can sense carbon dioxide given off in the breath of animals, drawing the females to the general area where they can feed. They then use their sense of detecting movement to find their victim. If you stay still for a moment after deer flies swarm, you will notice they settle down, once again trying to locate the object that is giving off carbon dioxide.
Controlling deer flies is nearly impossible. The use of insecticides to kill larva in their wet woodland home territories is not practical due to environmental concerns. Controlling adults is not realistic either, again because of the concerns of using insecticides in wetlands and because adults can fly in from neighboring properties that you cannot spray. At best, a spraying program might reduce the number of bites you may get over a short period of time.
Repellents containing DEET have very little or no effect on deer flies. Long sleeves, long pants and a large-brimmed hat are better for reducing bites than the repellents. Keep in mind, however, that mosquitoes and ticks often frequent the same areas as deer flies, so you may need that repellent for other pests.
My dad gave me a gadget a few years ago to catch deer flies when they land on your clothing. It is simply a yellow piece of tape coated one side with a sticky substance, similar to fly paper. The tape is placed on your hat or shoulders, and when the flies land on the flypaper side of the paper, they are stuck. I do not think it reduces the total number of bites I get; however, it does give me great satisfaction to see 40-50 deer flies stuck on the tape after an afternoon in the woods.