House Fly

Flying Insects—House Fly

Size

House fly adult is about 1/8-1/4 in (4-7.5 mm) long, female larger than male. Mature larva is about 1/4-3/8 in (7-10mm).

Characteristics

Adult face has 2 velvety strips, silver above and gold below; thorax has 4 narrow stripes; no pale spot behind head or rear tip of thorax; sides of abdomen usually pale; sponging mouth parts. Larva is eyeless, legless, tapered from rear to head, which is a pair of dark hooks.

Color

Adult is dull gray. Larva is cream colored and greasy looking.

Where

House flies are distributed worldwide, and throughout the U.S.

Habitat

Females lay eggs on almost any warm, moist material with adequate food supply for egg-laying and larval development. Most house flies stay within 1-2 miles of their larval habitat if food is available, though some have migrated up to 20 miles. During the day, they rest less than 5 ft. from the ground; at night, mainly above 5 ft., but near their food sources.

Diet

House flies are general feeders on liquids; attracted to many substances, from excrement to human foods. House flies can liquefy solid foods by regurgitation.

Biology

Adult female lays oval, white eggs singly in clusters of 20-50, laying 350-900 eggs in her lifetime. Eggs hatch in 8-20 hours. Larvae go through 3 instars in 3-7 days at 70-90 degrees F. Full grown larvae go to a cool, dry place to pupate, traveling up to 150 feet in 3-4 days. Pupa goes from yellowish to black during a period of a few days to a month, depending on temperature and humidity. After emerging, the body hardens and the wings dry within about an hour. Development from egg to adult can be as few as 6 days, with 10-12 generations per summer. Adults live 15-25 days.

Damage

House flies excrete and regurgitate whenever stopping to rest. They have many hairs and bristles, as well as sticky pads at the base of the leg claws. Therefore, they tend to transmit disease organisms, especially those associated with filth.

Control

1. Inspect to determine species and location of breeding and larval development activities. This is best done at night.

2. Remove larval development sites by emptying, cleaning, drying garbage containers.

3. Secure screens, seal holes, install various types of traps.

4. Use pesticides registered and labeled for use on house flies. When using any pesticide, always read entire label first, and obey all directions, observing all restrictions and precautions.