Deer flies are common, biting insects found across the globe, known for their painful bites. These insects pose a nuisance during warmer months, particularly in wooded and marshy environments, where they actively seek out hosts.
Physical Characteristics and Habitat
Deer flies typically measure between 0.25 to 0.5 inches in length, possessing a stout body. Their eyes often display iridescent green or gold bands, a distinctive feature. The wings are usually clear but marked with dark bands or patches. Some species may also exhibit yellow and black striping on their bodies.
These flies are abundant in damp, wooded, and wetland environments, including marshes, ponds, and streams, as their larvae require an aquatic or semi-aquatic habitat for development. Adult deer flies are strong fliers and are most active during summer months, with their activity peaking in June and July. They often rest on shrubbery or tall grass, waiting for hosts to pass by.
Biting Behavior and Health Concerns
Only female deer flies bite, as they require a blood meal to produce their eggs. Their mouthparts are blade-like, designed to cut into the skin and create an incision, allowing blood to pool. The fly then laps up the exposed blood. This cutting action results in an immediate, sharp pain, which many describe as similar to a bee sting.
A deer fly bite typically causes a red, raised bump that can be intensely itchy and painful, with swelling around the affected area. A small, clear blister might also appear at the bite’s center. While symptoms usually subside within a few days, persistent itching and scratching can lead to secondary bacterial infections if the bite is not kept clean. In some individuals, the saliva injected during the bite can cause allergic reactions, such as hives, swelling around the eyes, or even wheezing, though these severe reactions are less common. Deer flies are also known to occasionally transmit tularemia, a bacterial infection.
Prevention and Personal Protection
Wearing light-colored clothing, including long-sleeved shirts and pants, can help reduce the likelihood of deer fly bites. These insects are visually attracted to dark and moving objects, so lighter colors make you less noticeable to them. Additionally, wearing a hat can be effective, as deer flies are often attracted to the back of the head and scalp.
Applying insect repellents containing active ingredients like DEET or picaridin to exposed skin can offer some protection against bites. While some sources indicate that repellents may have limited effectiveness against deer flies compared to other insects due to their visual hunting, they can still deter them. Avoiding deer fly-prone areas, such as dense vegetation near water sources, is another strategy.