Ohio State University Extension Fact Sheet

Ohio State University Extension Fact Sheet

Entomology

1991 Kenny Road, Columbus, OH 43210-1000


Midges and Crane Flies

HYG-2129-97

William F. Lyon

Common Name Scientific Name
Non-biting midge Chironomus plumosus (Linnaeus)
Chironomus attenuatus Walker
Biting midges, punkies or no-see-ums Culicoides furens (Poey)
Crane flies Tipula spp.

Occasionally during April, May, and June, homeowners become alarmed by large swarms of gnat-like insects sometimes confused with mosquitoes. These non-biting midges are found near lakes, ponds or streams and may "dance" in swarms over the water, inciting fish to jump. Most occur in huge swarms or small compact mating swarms, and a "humming" can be heard over a considerable distance. After sunset, adults become active and fly to night-lights, entering structures through the slightest of openings. Piles of eight to twelve inches of dead midges may accumulate in unwanted places. A stench similar to dead fish may be observed. There are also biting midges, which are very tiny insects (sometimes called "no-see-ums"), that suck blood from humans, mammals, reptiles, and other insects. Bites can cause itching and, in sensitive individuals, welts and lesions that can persist for several days. Other species transmit diseases. Crane flies (some resembling overgrown or "giant" mosquitoes) are small to large size with extremely long legs (similar to "daddy-long-legs") that break off easily. Many have patterned wings. They are non-biting or stinging, but may cause alarm by their presence on sides of homes and elsewhere.

Identification

Non-biting midges are small (1/8-inch to 1/2-inch long), delicate, mosquito-like, but lack scales on their wings. Adults are humpbacked, brown, black, orange, or gray, lack a long beak (proboscis), and males have very feathery antennae. Larvae are often whitish, cylindrical-like, elongate or wormlike (up to 1/2-inch to 3/4-inch long) usually with paired prolegs, respiratory tubes absent on the prothorax, and have a dark head. Some are known as "bloodworms" or "red worms" due to the presence of hemoglobin in the blood. Others have a greenish color. Most live in fresh water while others are found in very moist soil, in wet moss, and under damp bark. Most larvae feed on algae or small aquatic plants.

Non-biting Midge
Non-biting Midge

Biting midges, punkies or no-see-ums are very tiny (less than 1/4-inch long), slender gnat-like flies. Some have narrow spotted or clear wings. Larvae are tiny, whitish, elongate, or wormlike, and are found in sand, mud, decaying vegetation, and water in tree holes.

Biting Midges, punkies, or no-see-ums
Biting Midges, punkies, or no-see-ums

Crane flies are small to large (3/16-inch to just under an inch long) long-legged, slender-bodied with a V-shaped suture across the thorax. Legs of all species break off easily so that perfect specimens are difficult to maintain in an insect collection. Many have patterned wings and resemble mosquitoes. The larvae, called "leatherjackets," develop a tough skin and can usually be found in damp soil feeding on decaying vegetable matter. Maggots are legless, have poorly developed heads, and are about one inch long when mature. They are usually associated with poorly-drained soils and sometimes occur in large, concentrated numbers. They are sometimes mistaken as cutworms.

Crane Fly
Crane Fly

Life Cycle and Habits

During peak emergence, extremely large populations of non-biting midges may create much annoyance simply by accumulating in freshly applied paints, hanging onto outdoor laundry, clustering on screens, etc. Summer resorts along lakes and other water frontage may have houses and buildings covered with these midges that enter around vent openings, air conditioning units, windows, doors, etc. The following day, these midges are found dead on window sills throughout the building. Their presence causes concern to homeowners and others. Sometimes, midges invade factories and contaminate fabrics, plastics, packed materials, etc. Other times, thick swarms can cause allergic reactions in susceptible individuals and even cause traffic hazards. Even economic losses occur when customers go elsewhere from certain motels and restaurants to avoid nuisance midges that are attracted to night-lights on their premises.

Female midges lay eggs in masses over open water or attach to vegetation. Eggs hatch in about 72 hours and the young larvae drop to the bottom of the lake, stream, etc., feeding as scavengers on organic debris (silty ooze, algae and plankton). The larval stage takes about four weeks followed by pupation lasting usually 48 hours. Pupa emerge from their pupal skin, rising to the water surface like a mosquito. Adults do not eat and have a short life span of five to ten days. Males swarm at dusk with mating occurring after females enter the swarm. Midges overwinter in the larval stage. They are beneficial as an important item of food for many freshwater fish and other aquatic animals.

Biting midges, punkies or no-see-ums are found especially along the seashore and the shores of rivers or lakes. Their small size is responsible for the name "no-see-ums" and their bite is far out of proportion to their size. Larvae are aquatic or semiaquatic, found in moist sand, mud, decaying vegetation of salt and freshwater marshes, ponds and streams. They are believed to be scavengers.

Crane flies occur chiefly in damp situations with abundant vegetation. Larvae are aquatic or semiaquatic, feeding on decaying vegetable matter. Others feed on living plants and may cause damage especially to turf and pasture. Some feed on flowers, certain vegetables and small fruits. Others are predaceous. Little is known of the adult feeding habits, but some possess a long slender proboscis and feed on plant nectar. Crane flies do not bite or sting humans.

Control Measures

No control measures for midges are entirely satisfactory when large bodies of water are nearby. Locating the source of breeding is best. If possible and practical, locate standing water on your premises and eliminate it. Midges may fly as far as a quarter of a mile from the breeding site such as a lagoon, drainage ditch, standing water, lake or pond. They can also develop in and around buildings in well-watered soils and occasionally in standing water from air-conditioning units on building roofs. Check stagnant, polluted water accumulating in bird baths, clogged rain gutters, water-holding tree stumps, flower pots, old tires, etc. Sometimes, it is often best to wait out the one-to two-week emergence period for a particular species, hoping that additional emergence periods will not occur. However, several species emerging at different times may occur in the same locality, lasting six to eight weeks or longer at 75 degrees F to 80 degrees F during hot, muggy weather.

Prevention

Houses and buildings with outside lighting will attract large numbers of non-biting midges. Move light away from sensitive areas such as doorways, windows, patios, etc. Avoid the use of unnecessary lights until 45 minutes after sundown since 90 percent or more of flight activity takes place before that time. Sometimes, eggs are laid on surfaces around lights and on buildings. These egg masses can become unsightly and smear when wet. By replacing a 100-Watt mercury vapor light (ultraviolet energy) with a 50-Watt high-pressure sodium vapor light, midge concentrations are significantly reduced. (Lights least attractive to insects are sodium vapor or halogen with pink, yellow or orange tints and dichrom yellow bulbs.) Blacklight traps (bug zappers) will kill midges, but unfortunately often attract more midges into the area than are killed. Larvae have been controlled in small bodies of water by stocking with carp and goldfish at the rate of 150 to 500 pounds of fish per acre.

Biting midges apparently do not travel far from the place where larvae develop, and one may often avoid punkie attacks by simply moving a few yards away.

Insecticides

Small bodies of landlocked water may be treated with insecticides, but these bodies of water may or may not be the source of nuisance midges. Several of the commercial insecticides labeled for midge control are for application only by Public Health Officials, trained personnel of Mosquito Abatement Districts, and licensed pesticide applicators. For control of midge larvae, one can apply temephos (Skeeter Abate) two percent or five percent, in standing water, shallow ponds, lakes, woodland pools, tidal water, marshes, swamps and waters high in organic content (highly polluted water). For adult control, one can apply permethrin (Biomist) ULV, using any standard ULV ground applicator capable of producing a nonthermal, aerosol spray with droplets ranging in size from 5 to 30 microns. Also, labeled for adult control is chlorpyrifos + permethrin (ULV Mosquito Master). Permethrin 6.92 to 10 percent EC is a broad spectrum multiuse insecticide, providing quick knockdown.

Certain formulations of pyrethrins are labeled for outdoor adult midge control. Some licensed pest control operators use total release of aerosols and fog (ULV) for adult control. Granular pesticides have been used in barrier treatments around structures.

For additional information on insecticides labeled for midge control, contact:

Clarke Mosquito Control Products, Inc.
159 Garden Ave.
P.O. Box 72197
Roselle, IL 60172
1-800-323-5727
FAX 1-800-832-9344

Crane flies are short-lived and will soon disappear. There is no need to kill these adult insects. Repellents containing DEET and long-sleeved shirts and long-legged pants provide relief against biting midges.


All educational programs conducted by Ohio State University Extension are available to clientele on a nondiscriminatory basis without regard to race, color, creed, religion, sexual orientation, national origin, gender, age, disability or Vietnam-era veteran status.

Keith L. Smith, Associate Vice President for Ag. Adm. and Director, OSU Extension.

TDD No. 800-589-8292 (Ohio only) or 614-292-6181



| Ohioline | Search | Fact Sheets | Bulletins |