Midges breed in water and under summer conditions several generations may occur each year. Adults are relatively short lived, about 10 days at most. Their presence causes a great annoyance to homeowners who live near the aquatic breeding sites. In some instances they may be so numerous as to cover sides of houses. The males of many species swarm at dusk and mating occurs when females enter the swarms.
Larval stages serve as food for fish in the aquatic habitat.
The adults may be attracted to lights at night. The adults do not fly very far. In contrast to the caddisflies, these insects hold the wings close to the body giving them a flattened appearance. Adults are usually found near water in shady places. The nymphs are found under stones, around branches, or in debris in the stream bed.