Identification and Life Cycle
Filth flies (domestic) are typically found around the outside and inside of structures, and can be an extreme nuisance. Some domestic flies feed on blood, while others are scavengers and feed on decaying matter.
The Blow Fly, resembles a house fly, and is twice the size, approximately 1/2 – inch long. It is metallic blue, blue or green in color. Their life span can be 2-4 weeks, and lay up to 2,000 eggs in its lifetime.
The Bottle Fly, is approximately 1/2–inches long with large red eyes. Its head and thorax is gray and abdomen is a shiny metallic blue. The adults can live up to 4 weeks, laying eggs in clusters of 200 at a time.
The Cluster Fly, is about the same size as a house fly; 1/4 – inch in size. It is gray with black markings, and yellow hairs on its thorax. Their life span is 4-6 weeks. They lay eggs in the soil in summer months.
The Flesh Fly, is approximately 1/2- inch long. Adults have a gray and black checkerboard pattern on abdomen with a life span of 2-4 weeks. The female does not lay eggs, but retains them in her body, and can birth up to 300 larvae. Their life span is 2-4 weeks.
The Stable Fly, is about the same size as a house fly, a 1/4 – inch in size. It is gray in color with dark stripes on their back and a checkerboard pattern on its abdomen. Their life span is approximately 3 weeks, and the female can lay up to 1,000 eggs in a lifetime.
Habits and Damage
All flies belong to the insect order, Dipetera, meaning “two-winged”. A fly’s life cycle consist of 4 stages; egg, larva, pupa and adult. Eggs are laid in a variety of decaying or organic matter and hatch into larva (resembling pale maggots), then they pupate. At this time they do not feed, and soon emerge as an adult in 7-14 days.
Filth flies can pick up disease-causing pathogenic organisms that they can pass on to humans such as tapeworm, typhoid, hookworm, salmonella and more. They feed on and lay their eggs in organic material, such as garbage, sewage, and decomposing animal and vegetable matter. This habit makes them scavengers, and because they are in contact with unsanitary conditions, this enables them to contaminate food and surfaces.
Blow Flies and bottle flies lay eggs in decomposing organic matter such as garbage, animal manure and decaying vegetables. Garbage cans are the most common sources of filth flies in urban areas. They are commonly found in homes, restaurants and supermarkets.
Cluster Flies are seen more in the spring and fall. They can be found indoors forming compact clusters and hibernating typically in upper rooms, attics or window frames. They deposit their eggs on the soil and the larva or maggots then burrow into earthworms to feed.
Flesh Flies found in the home may have been attracted to odors of decay or just seeking shelter. The larvae commonly live in garbage, manure and animal carcasses. Flesh flies can breed in dead rodents and birds in attics or the wall voids of houses.
Stable Flies are similar in size and appearance of a house fly. Making this fly different, both the male and female has a long, pointed proboscis (sponging mouthpart) that extends forward beyond its head to pierce the skin and draw blood. This “bite” can be painful. Females deposit their eggs in a variety of decaying plant and animal matter. They can be found around stables, houses, along seashores, and near dog kennels.
Prevention and Management
The best strategy for controlling filth flies is to follow good sanitation, inspection and exclusion practices. An Integrated Pest Management (IPM) program can help maintain a pest-free environment.
It is important to properly identify the species and alter conditions in and around a home or building that flies are attracted to. By eliminating their breeding sites on which they lay eggs, you can prevent further fly infestations.
The following steps can be taken to help prevent or reduce a potential problem with flies.
- Correct any moisture problems around the structure such as water leaks in roof, walls and plumbing fixtures.
- Tightly seal plastic bags containing garbage before disposing in receptacles or dumpsters.
- Promptly remove manure, rotting mulch, lawn clippings and animal carcasses from the property.
- Empty food garbage receptacles daily and keep trash containers clean.
- Clean up sugary spills, dead insects, and greasy items on counters and floors.
- Repair holes in window screens & make sure that screens & windows close tightly.
- Eliminate shallow, stagnant pools of water that will attract flies and other insects.
- Inspect your potted house plants for excessive soil moisture which can attract flies.