Summer pests are small insects that can be a nuisance during the warmer months. Common summer pests include gnats, which are small flies that often swarm around people and animals; skeeters, which are a type of MOSQUITO; mosquitoes, which are blood-sucking insects; and midges, which are small flies that feed on plants. All of these pests can cause discomfort and annoyance, and can even spread diseases.