Understanding Phorid Flies
Phorid flies, often called scuttle flies, are small insects commonly mistaken for fruit flies due to their similar size. They measure only a few millimeters in length, ranging from 0.5 to 6 millimeters. A distinguishing characteristic of these flies is their humped or hunchbacked thorax. Their flight pattern is erratic, involving a rapid, darting movement.
These flies are known for their quick, scuttling run across surfaces, which gives them their common name. Phorid flies undergo a complete metamorphosis, progressing through egg, larval, pupal, and adult stages. Their life cycle can be remarkably short, completing in as little as 14 days under optimal conditions, enabling rapid population growth.
Do Phorid Flies Bite Humans?
Phorid flies do not possess mouthparts for biting or piercing human skin. Their mouthparts are designed for sponging or lapping up liquid food sources, not for drawing blood. This anatomical difference means they are physically incapable of inflicting a bite. Any sensation perceived as a bite from a small fly is likely due to another insect, such as a mosquito or biting midge, or a misidentification.
Their diet consists of decaying organic matter, including rotting fruits, vegetables, and animal carcasses. They also feed on fungi, molds, and microbial growths found in moist conditions. They may consume sugary liquids, but they do not seek out blood as a food source. Therefore, concerns about phorid flies transmitting diseases through bites are unfounded.
Why Phorid Flies Infest Human Environments
Phorid flies are attracted to moisture and decaying organic materials, readily available in many human environments. They thrive in places where moisture accumulates and organic matter decomposes, such as clogged sink drains, garbage disposals, and neglected floor drains. Rotting produce, overflowing garbage bins, and even pet waste can also serve as breeding sites. Their presence often indicates an underlying sanitation issue within a structure.
These flies can also infest less obvious locations, including areas where plumbing leaks or where dead animals, such as rodents, are decaying within wall voids or crawl spaces. Their rapid reproduction rate means even a small, overlooked source of organic matter can lead to an infestation. Their numbers can become a nuisance, and they have the potential to contaminate food surfaces by carrying microorganisms from their breeding sites.
Controlling Phorid Fly Presence
Control of phorid flies centers on identifying and eliminating their breeding sources. This involves sanitation practices to remove decaying organic matter and address moisture issues. Regularly cleaning and flushing drains with hot water or a biological drain cleaner can remove the organic film where larvae develop. Disposing of rotting food, emptying garbage cans frequently, and storing food in sealed containers are important steps.
Addressing hidden moisture problems, such as leaky pipes or overflowing drip pans, will remove breeding grounds. For persistent infestations, especially when the source is difficult to locate, professional pest control assistance may be necessary. While vinegar traps can temporarily reduce adult fly populations, they do not address the root cause and are not a long-term solution. Focusing on source elimination is the most effective strategy for managing phorid fly presence.