Insects, Spiders, Mice and More... Cercopia Moth University of Nebraska-Lincoln
University of Nebraska Cooperative Extension in Lancaster County
444 Cherrycreek Road, Lincoln, NE Email

Educational Resource Guide #262

Midges: Non-biting Gnats
by Barb Ogg, Ph.D, Extension Educator

Midges are widely distributed in the United States and Canada. The most common midges people complain about are non-biting nuisance pests belonging to the family Chironomidae. The general public often refers to them as "gnats." 

Chironomus midges are similar in appearance to the mosquito, but they cannot bite. Midges have plumose antennae that resemble a small feather. They are very small--none larger than 1/8-inch long. The adult midge may be a variety of colors from dark brown to green. 

Adult Male MidgeMidge populations are dependent on water--this includes a variety of sources including wet soil or plant waterings. In the Lincoln area, homeowners in the Capital Beach area are perennially faced with large numbers of midges during periods of the warmer months. Typically, male midges swarm in large numbers at dusk. Mating occurs when females enter the swarm. 

Like mosquitoes, the midge larval stage is aquatic. The adult females lay eggs in masses over open water or attached to aquatic vegetation. They hatch in several days and the young larvae drop to the bottom where they build tubelike structures of bottom debris held together by strands of silk. One interesting fact is that the blood of some midge larvae (called bloodworms) is red, unlike the blood of most other insects. It is red because it contains hemoglobin which binds tightly to oxygen. This is necessary because of the stagnant, low oxygen conditions that may be present where these larvae live. 

The larvae are scavengers, feeding on bottom debris. Under favorable conditions, they are larvae for about four weeks and then they pupate for several days. Just before emergence, the pupa rises to the water surface, emerging from the water surface, like a mosquito. Larval midges are very beneficial because they serve as food for fish. 

During their swarming activities, adults may be attracted to lights. Buildings with outside lighting will attract large numbers of these insects. If these lights are around vent openings, air conditioning units or windows, the insects can find ways into the structure. The next day, dead midges can be found on window sills, possibly through the entire building. This causes concern to homeowners and occupants of office buildings, hotels and healthcare facilities. 

Control. Avoid the use of unnecessary lights around dusk when midges swarm. If midges are entering the house, make sure that vent openings and other entry points are sealed.

Pools of standing water should be drained if possible; yet, it is not possible to prevent midges from breeding in lakes and permanent bodies of water. 

Area insecticide fogs applies to foliage will provide some temporary control of adults. updated June 5, 2002

Back to Flies, Gnats and MosquitosReturn for more information on Flies, Gnats and Mosquitos

Looking for information about a specific insect pest or your local wildlife? Visit here.


USE OF THE EDUCATIONAL MATERIALS: You may reproduce the Educational Resource Guides for educational purposes but not for sales purposes (unless otherwise indicated as a sales item--these items may not be reproduced). Videotapes are copyrighted and may not be reproduced. If you have questions about using any photographs or images, visit Credits for use. You're also welcome to link to "Insects, Spiders, Mice and More" from your website. Please credit: University of Nebraska Cooperative Extension in Lancaster County (http://lancaster.unl.edu/enviro/pest/bug.htm)

About This Site line Weekly Features
Insects and Spider Educational Resources line Wildlife Educational Resources
Head Lice Resources You Can Trust line Identifying Your Pest line Credits

University of Nebraska Cooperative Extension in Lancaster County
444 Cherrycreek Road, Suite A, Lincoln Nebraska 68528-1507
Phone: 402-441-7180 | Web Site: http://lancaster.unl.edu

4-H & Youth | Agriculture & Acreage | Environment & Natural Resources | Family Living
Food: Safety, Nutrition & Cooking | Gardening | Home Environment |
Insects, Spiders, Mice & More | Nutrition Education Program | NEBLINE Newsletter

Parents, Teachers and Students: Consider the University of Nebraska-Lincoln

University of Nebraska Cooperative Extension in Lancaster County Confidentiality Statement

University of Nebraska Cooperative Extension educational programs abide with the nondiscrimination policies of the University of Nebraska-Lincoln and the United States Department of Agriculture.
All Rights Reserved 1996-2004