Female biting gnats bite people and animals to develop their eggs, causing swelling and irritation. Sensitive individuals may also experience allergenic asthma and nausea. Biting gnats are also known as black flies, buffalo gnats and turkey gnats.
Biting gnats are small and humpbacked. Their bites usually focus on the head area. They usually feed during sunny, warm days, especially in mid-morning and evening. Biting intensifies before storms and during overcast conditions.
Common insect repellents that contain DEET offer some protection against gnats, although the may swarm around you even when you're using a repellent.
Dark colors attract biting gnats, so light-colored clothing is the best choice if you know you will be in an area where they are likely to be present. Because they like to attack the head, a light-colored hat that covers the ears can be particularly helpful.