greenbottle flies (Lucilia illustris and Phaenicia sericata),
Green Bottle Fly
Green Bottle flies have striking, metallic, blue-green or golden coloration with black markings. They also have black bristle-like hairs and three cross-grooves on the thorax. The wings are clear with light brown veins, and the legs and antennae are black.
Range from 1/4 to 3/8-inch in length.
As with Flesh flies, Green Bottle flies feed and breed almost exclusively on dead or rotting flesh, manure and other decomposing material, as they are attracted by the organic odors of decomposition.
Females deposit their eggs on these materials that the larvae, or maggots, then eat after hatching. They then burrow into shallow soil where they pupate, developing into adults in 1-3 weeks. As with flesh flies, the larvae of the green bottle fly are also used by forensic entomologists to determine the time of death in homicide investigations.
The Green Bottle fly is very common, and can generally be found anywhere that might contain dead or rotting flesh: farms, slaughterhouses, fishing docks, dumpsters, rendering plants, dumpsters, etc. They can also be found inhabiting animal feces and may deposit their eggs in the open wounds of living animals and even humans.
Green bottle flies usually do not occur in large numbers inside buildings. If they do, it means that the breeding site is probably indoors or in a place near an open vent, window, or doorway. Check chimneys, attics, crawl spaces, vents, under floorboards, and above ceiling tiles for the source, which is often a dead rodent, lizard, or other animal that has begun to decompose indoors.
A type of biotherapy exists (and is sometimes used, even today) known as Maggot Debridement Therapy (MDT). This involves the intentional introduction of specially selected and tested, disinfected fly larvae (maggots) for cleaning non-healing skin and soft-tissue wounds.
Medicinal maggots have three actions: 1) they debride (clean) wounds by dissolving the dead (necrotic), infected tissue; 2) they disinfect the wound by killing bacteria; and 3) they stimulate wound healing.
Removing the breeding sites of green bottle flies is the best method of non-chemical control. Proper sanitation is required, and includes cleaning areas where garbage is stored, removal of dead and decomposing animals and fish, and dispersal of decaying organic material, even compost piles.
Keeping green bottle flies from coming indoors involves properly fitted doors and windows which inhibit the migration of these flying pests. Check for screens that are loose or torn, and inspect for areas where rodents or birds may gain access to the building and possibly die while inside.
Be sure to seal all cracks around doors and windows, and install mesh screens behind any vents or other openings that might allow the passage of flies and other winged insects into the dwelling.
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