NON-BITING FLIES

Non-biting flies are extremely important pests because they are everywhere and they also transmit a wide variety of diseases. For example, the house fly has been found to harbor over 100 different pathogenic organisms.
Flies feed on a variety of food sources but usually they feed on decaying or fermenting organic matter. Fly control can pose a problem because their food sources need to be determined and the adult flies may be some distance from it. Therefore, fly management involves:
  1. Correct Identification of the fly
  2. Location of the food and breeding sites
  3. Elimination of the food and breeding sites
  4. Preventative measures
  5. Insecticide treatment if needed

IDENTIFICATION

Flies can be easily identified by the adult stages of the insect. The larval stages, called maggots, are the ones who will be found where the "feeding habits" section below points to.
Cluster Flies
Identifying Characteristics: These relatively large flies are dark gray, non-metallic in color. The thorax is lacking distinct stripes but does possess numerous short golden hairs. Their movements are sluggish and when crushed, emit a buckwheat honey odor. Their name comes from the fact that they will overwinter inside in large clusters behind pictures, in attics, behind wall voids, etc.

Feeding Habits: The larvae are parasites of the common earthworm.

Blow / Bottle Flies
Identifying Characteristics: Color partly or wholly metallic blue, green, or dull brassy, sometimes black. Feeding Habits: Most species develop in meat or animal carcasses, but they will also develop in animal excrement, decaying vegetation, and / or garbage. Dead rodents, birds, and other small animals can be the source of flies within the structures while dog excrement and garbage are common exterior sources.
Fruit Flies
Identifying Characteristics: Also known as vinegar flies, these insects are dull tan to brownish yellow or brownish black in color with eyes that are usually red. They are small, usually about 1/8 inch in size.

Feeding Habits: These flies develop on fruits and vegetables such as bananas, grapes, peaches, pineapples, tomatoes, mustard pickles, potatoes etc. as well as fermenting liquids such as beer, cider, vinegar, and wine. They will also develop in the briny or vinegar like liquids at the top of imperfectly sealed canned fruits and vegetables.

House Flies
Identifying Characteristics: The color of this fly is dull gray with the face having 2 velvety stripes, each silver above and gold below. The thorax has 4 narrow black longitudinal stripes.

Feeding Habits: Although these flies have been shown to migrate as much as 20 miles, most stay within 1 to 2 miles. Eggs are laid on almost any warm, moist material with sufficient food for larval development. This ranges from excrement to human foods. Therefore, these flies are able to transport a wide variety of diseases.

Drain Flies
Identifying Characteristics: Drain flies, also known as moth flies, filter flies, sewage flies, or psychodids, are yellowish to brownish gray to black in color. Their wings are broadly oval and are held roof like over the body during resting. They are also small in size, only 1/16 to 1/4 inch.

Feeding Habits: Eggs are laid on the surface of the gelatinous film which covers filter stones of sewage treatment plants or which lines the water-free portions of drain pipes. The lavae feed on the algae, bacteria, fungi, microscopic animals, and sludge of this film.

INSPECTION

Once the type of fly has been determined, then an inspection to find the breeding source of the fly infestation should be performed. The purpose is to find ALL sources.

SANITATION

This involves the removal of the breeding material. Specifically:
  • Cluster Flies: This is impractical since the breeding source is earthworms. Prevention is the only practical method of cluster fly control.
  • Blow or Bottle Flies: Removal of dead and decay matter as well as keeping garbage containers clean.
  • Fruit Flies: Keeping fruit refrigerated and beer and wine spills cleaned immediately.
  • House Flies: Keeping garbage cans tightly sealed, dog excrement from building up, and any other breeding material cleaned up.
  • Drain Flies: Keeping drains cleaned by pouring a caustic drain cleaner down the drain regularly, according to directions.

PREVENTION

This involves exclusion by using screening, caulking, tight fitting windows and doors, etc. You should also consider using air curtains, insect light traps, sticky traps, etc. to reduce or eliminate the flies from entering.

TREATMENT

Insecticide applications involve using appropriately labeled products on larval habitat, adult resting surfaces, around crevices such as attic vents and facial boards, or on a room by room basis, depending on the infestation. Insecticide treatments indoors should only be done when all the above has been done and there is still a large infestation. See Pestdude's PESTICIDES page for more information on pesticides.

See also: HOW TO CHOOSE A PEST MANAGEMENT PROFESSIONAL

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