Fruit flies, tiny insects often seen hovering around ripe produce, do not bite humans because their mouthparts are not designed for piercing skin. Many people mistakenly believe fruit flies bite due to encountering other small, biting insects.
Fruit Fly Characteristics
Fruit flies, commonly known as Drosophila melanogaster, are small insects measuring about 2-4 millimeters in length. They typically have a tan to brownish-yellow body with distinct red eyes. These insects are strongly attracted to fermenting fruits, decaying organic matter, and sugary liquids like wine, beer, or fruit juice. They often appear in kitchens where such food sources are exposed.
The mouthparts of a fruit fly are adapted for sponging or lapping up liquids, not for biting or piercing. Their feeding apparatus, primarily the labium, contains fine tube-like structures called pseudotracheae. These structures allow them to absorb liquids, effectively soaking up their food rather than cutting or puncturing it.
Why People Might Think They Bite
The misconception that fruit flies bite often arises from confusing them with other small, flying insects that do possess biting mouthparts. Insects such as biting midges, sometimes called “no-see-ums,” are tiny and can inflict painful bites. These midges are typically 1-3 mm long and have specialized mouthparts with minute cutting blades that lacerate the skin to feed on blood. Their bites can cause itchy welts.
Drain flies, also known as moth flies, are a common household nuisance often mistaken for fruit flies. They have fuzzy, moth-like appearances and are attracted to organic material in drains and sewers. While a nuisance, drain flies do not bite humans. Fungus gnats, often found near houseplants, also do not bite but are sometimes confused with fruit flies.
Controlling Fruit Fly Presence
Even though fruit flies do not bite, their presence can be annoying, and they can contaminate food surfaces by carrying bacteria. Effective control begins with removing their food sources and breeding grounds. Storing ripe produce in the refrigerator and promptly cleaning up any spills, especially sugary ones, can help prevent infestations. Regularly emptying trash cans, particularly those containing food waste, is also important.
Simple homemade traps can effectively reduce fruit fly populations. A common method involves placing a small amount of apple cider vinegar in a jar, adding a few drops of liquid dish soap, and covering the opening with plastic wrap or a lid with small holes. The vinegar attracts the flies, and the dish soap breaks the surface tension of the liquid, causing them to drown. Another option is to use old wine or beer as bait in a similar trap.