Image via flickr by Judy Gallagher
Spotting just one or two flesh flies isn’t a cause for concern, but you should be alert to any significant number of these flies. Learn how to identify flesh flies and what to do about their presence.
Flesh flies are a type of mid-sized flying insect known to lay eggs in carcasses or open wounds. They are often associated with remains. Infestations in the home are uncommon, but it’s essential to act upon a swarm of flesh flies.
Flesh flies typically range from 1/3 inch to 1/2 inch long. They are gray with a distinctive checked pattern on the top of the abdomen. The thorax has three dark stripes, and many species of flesh flies have a reddish tip on the end of their abdomen. They are similar in size to houseflies and might initially be mistakenly identified as such. However, the flesh fly’s patterning is easily identifiable if you get a close enough look when it lands.
Flesh flies are prevalent and may be found throughout the United States. Flesh fly eggs stay inside the body of the female until they’re ready to hatch. She then lays them directly in the food source that she has selected; this is often the body of a recently deceased animal, such as a mouse. Other suitable materials are spoiling meat or manure.
Some species of flesh fly have different preferences. The Sarcophaga Kelly species lays her larvae on the underside of grasshoppers’ wings, where they become a deadly parasite. The Wohlfahrtia vigil fly may deposit larvae on infants’ skin. Other species leave their larvae in bee and wasp nests.
The larvae emerge from the eggs and dine on their food source. It takes a few days for the larvae to grow large enough to leave. At this point, they will crawl away to pupate. When they’re outside, the larvae will typically stay close by, burrowing into the nearby soil. Inside the home, they may travel much farther. The larvae will emerge as adults, roughly 10 to 14 days later.
Flesh flies will rarely infest buildings in large numbers. A few flies might make their way indoors, drawn by food odors and the warm or cold air currents moving through open doors and windows. However, if you see several flesh flies, this usually indicates that they are breeding somewhere nearby, which is a major cause for concern.
If you see more than one or two errant flies, you may want to look for a breeding source in the building; this might be a dead bird or mouse in the attic or a wall cavity. A significant number of flesh flies could indicate another type of infestation in the home, which is feeding these insects.
Other common sources of breeding material for flesh flies are garbage dumpsters. If you live near a meat rendering facility or processing plant, this could also attract flesh flies to the area. In some cases, flesh flies may be attracted to breeding facilities, shelters, farms, or other properties with many animals. Here, they will seek out open wounds. Protect your animals from flesh flies by properly treating injuries.
Flesh flies can cause many problems. They can transmit bacteria and other organisms that they pick up while landing on feces, carcasses, and other unsanitary material. These flies have been known to carry salmonella, streptococcus, E. coli, and the poliovirus. They may also transmit myiasis or dysentery. Flesh flies can cause intestinal infections in those who eat food that’s contaminated with flesh fly larvae.
If you believe that you have a flesh fly infestation, a pest control professional can help you track down the source of the problem. It’s important to know where the flesh fly larvae are coming from to exterminate these troublesome insects properly. It’s rare for a flesh fly problem to become so severe that you need chemical treatment. It’s more likely that you will need to accurately identify the fly, find its source of breeding material, and get rid of anything that’s providing a food source for the larvae.
An experienced exterminator can help you properly sanitize your space. He or she can also point out points of entry, such as gaps around windows and doors where flesh flies are entering your house. If the infestation is severe, your exterminator may place traps or use chemical baits and aerosol products to get rid of the flies.
Flesh flies are unpleasant pests. However, they can serve a purpose for researchers, scientists, and detectives. Learn more about flesh flies and their purpose.
Flesh fly larvae can help inform forensic entomologists about the time of death. A close examination of the state of the larvae may provide a timeline for the course of events in a criminal investigation; this is also true of other types of flies, so forensic entomologists need to distinguish between one species and another to make the proper calculations.
Though you don’t want flesh flies in your home, they do play an essential role in nature. They are part of the natural decomposition process that breaks down carcasses and returns nutrients to the soil. In wild areas, flesh flies help balance the ecosystem.
Flesh flies are extremely attracted to light. You may find them buzzing loudly near light sources that are around their breeding areas. UV light traps are very effective at trapping these flies if you’re struggling to control large numbers of them.
If you believe that you have flesh flies in your home, speak with a pest control professional to make sure that you’ve identified the pest correctly. The exterminator can then help you come up with a treatment plan suited to the problem.