Summertime pest can refer to a variety of insects, such as mosquitoes, skeeters, and gnats. Mosquitoes are eight-letter flying insects that feed on the blood of humans and other animals. Skeeters are seven-letter flying insects that are closely related to mosquitoes and also feed on the blood of humans and other animals. Gnats are four-letter flying insects that are smaller than mosquitoes and skeeters and feed on the nectar of plants. All three of these insects can be a nuisance during the summer months.