Bottle Flies: Identification, Behavior, and Control Strategies

Green and Blue Bottle Flies: Overview

Green and Blue Bottle Fly on a leaf

Green and blue bottle flies are easily identifiable by their metallic blue or green sheen, distinguishing them from other flies, such as house flies. Commonly referred to as “blow flies,” these insects encompass several species that share similar life cycles and habits.

Habitat and Infestation

These flies are prevalent in urban areas. When infestations occur, the sources of their larvae are typically traced back to either garbage or dead animals, particularly rodents. Identifying and eliminating these sources can lead to effective control. Poorly maintained garbage cans are a common breeding ground for these flies, even if they appear to be in good condition. For instance, small vent holes in metal garbage can lids allow adult flies to enter, enabling a single female fly to lay hundreds of eggs.

Homes near slaughterhouses, meat processing plants, or garbage dumps are especially vulnerable to infestations due to the abundance of suitable larval food sources, primarily decaying meat.

Behavior and Characteristics

Green and blue bottle flies are active and noisy, often more bothersome indoors than house flies. A large population indoors can indicate the presence of a dead animal hidden within walls, attics, or crawl spaces. For example, a dead animal in an attic can lead to larvae emerging in living spaces, while unemptied garbage cans can allow larvae to migrate into kitchens.

Larvae are identifiable by the fleshy protuberances surrounding their spiracles. While blow flies are primarily associated with dead animals, the larvae of the humpback fly are often found in mausoleums and decaying organic matter.

Attraction and Reproduction

Even in the absence of visible dead animals, these flies may enter homes drawn by specific odors, such as methane, which is emitted from decaying organic matter. Methane also originates from gas leaks, attracting flies to the source.

Female green and blue bottle flies can lay up to 600 eggs in their brief lifespan of two to three weeks. They typically prefer to lay eggs on decaying animal matter but will also use manure or decomposing vegetable matter. The larvae feed on the surface material before burrowing deeper and eventually pupating in the ground.

Once they emerge as adults, they may be noticed around plumbing pipes, heater ducts, and light fixtures. Their heavy flight and buzzing sound make them particularly noticeable. Monitoring methods, such as light traps, are effective for managing populations in settings like meat processing plants.

Control of Green and Blue Bottle Flies

Effective control of green and blue bottle flies, also known as blow flies, involves a combination of preventive measures and active extermination strategies. Here are several approaches to managing infestations:

1. Sanitation and Waste Management

Proper sanitation is crucial in preventing infestations. Regularly cleaning and maintaining garbage cans, ensuring they are tightly sealed, and promptly disposing of waste can significantly reduce breeding sites. Flies are often attracted to decaying organic matter, so eliminating potential food sources is essential. Keeping areas around garbage disposal units and compost piles clean and well-maintained can help mitigate fly populations .

2. Physical Exclusion

Sealing entry points in buildings can help prevent flies from getting indoors. Installing tight-fitting screens on windows and doors, as well as using door sweeps, can reduce access. It’s also important to ensure that any gaps or cracks in the building’s structure are sealed .

3. Traps and Baits

Using fly traps can be an effective control method. Light traps are particularly useful in commercial settings, such as restaurants and food processing facilities. These traps attract flies, capturing them and reducing the population. Additionally, bait stations can be employed in strategic locations to lure and kill adult flies .

4. Insecticides

Chemical control may be necessary in cases of severe infestations. Pyrethroid insecticides are commonly used against adult flies and can be applied in areas where flies are known to congregate. However, it is essential to follow label instructions and consider potential impacts on non-target species, including beneficial insects .

5. Professional Pest Control Services

For persistent or large-scale infestations, enlisting professional pest control services may be the best approach. You can call Traffic Pest Solutions if you are in LA County or can call a local pro near you