Biting Flies

There are several different types of flies that people refer to as “biting flies”.

Black Flies

One of the most notorious biting flies is the black fly. Some people use the name buffalo gnat or turkey gnat to describe these insects. These flies are often found near shores. After a blood meal, the females deposit their eggs in the water or on an object near the water. In some areas, these flies occur in large swarms.

Black flies deliver a painful bite. The bite site can become swollen. Cattle and other livestock can suffer from black fly bites. These flies can be the vectors of several diseases to animals and humans.

Horse Flies

Deer and horseflies actually bite cattle and mules as well as deer, horses, and people. They are large flies. Some species can reach more than an inch in length.

They develop in water or in moist soil.

Some of these flies can transmit tularemia that they get from rabbits and hares. Some of them can also transmit several diseases to domestic animals.

These flies are strong fliers, but do not fly well on windy days.

Sand Flies

There are tiny flies that people call sand flies or no-see-ums. They are common in coastal areas and along waterways. Although they are tiny, these flies deliver a painful bite because of the type of mouth that they have. They cause a red, inflamed spot that can itch for several days.

Stable Flies

Stable flies are also included among the biting flies. These are medium-sized flies, about ¼” long. They look so similar to houseflies that many people call them biting houseflies. When they occur near the ocean, people often call them beach flies.

Stable flies feed in the morning and evening, but they feed less on cloudy or windy days. They attack people’s ankles. They attack animals on their undersides. This can seriously affect milk production in dairy cattle.

Symptoms of Fly Bites

The species of biting flies produce slightly different physical reactions in the humans they bite. For example, horse and deer flies leave behind itchy, red, swelling welts. Black flies may produce small puncture wounds or cause golf ball sized swelling and induce black fly fever, which is characterized by headaches, nausea, swollen lymph nodes, and fever. Finally, biting midges leave behind itchy, irritated, and small bites.

People may contract secondary bacterial infections if they persistently scratch at bite sites. Additionally, individuals who are allergic to biting fly saliva may experience life-threatening reactions. Severe symptoms include rashes, swelling around eyes, wheezing, weakness, and dizziness.


The first step to treating fly bites is cleaning the affected areas with mild soap and water. Icing bites for 15 minute increments over the course of a day helps prevent swelling and infection. If bleeding occurs or severe symptoms present, individuals should seek expert medical advice immediately.

Biting flies are almost impossible to control outdoors. They can be kept out of houses by careful maintenance and by keeping doors and windows screened or closed.

People who live in an area where biting flies are a problem often use insect repellant products when they go outdoors. When they go out, people usually dress in loose-fitting clothing to avoid leaving skin exposed. They also learn what times to avoid going outdoors and they avoid the feeding areas of their local biting flies.