What Are They?
Found in and around restaurants, homes, bars, fruit markets and other establishments that sell or utilize produce, the fruit fly is a considerable pest throughout the United States. Although fruit flies quickly become nuisances when they enter homes, the insects do not bite humans because they do not feed on blood or possess the ability to pierce human skin. Their destruction is mostly limited to the contamination of ripe or decomposing fruits and vegetables as they have sponge-like mouthparts used to suck up liquefied plant matter. Though fruit flies live out their entire life cycle in approximately a week, they lay hundreds of eggs during that time in the skin of ripe fruits, uncovered trash bins, and garbage disposals.
Scientific Classification: Drosophila spp.
Also known as vinegar or pomace flies, fruit flies feed on the yeasts released by decaying organic matter such as fruits and vegetables.
What Do They Look Like?
Below are some characteristics of fruit flies.
Size: Smaller than a housefly, fruit flies generally measure up to 1/8 inches in length, including the wings.
Color: The fruit fly exhibits a yellow to tan thorax, a yellow abdomen and black striping on the dorsal surface of the abdomen.
Body: With a single pair of wings on the middle segment of the back, a round head with red or black compound eyes, and short antennae, the fruit fly appears similar to other fly species.
While females are moderately larger than males, members of both sexes possess halteres, which enable the insects to remain balanced during flight.
Fruit flies can be distinguished from other fly species by the presence of feathery arista on their antennae.
Do They Bite?
While considered a general annoyance, fruit flies are not known to bite humans or animals. Lacking the proper mouthparts to bite or blood feed as certain other flies do, the insects typically remain attracted to sweet or other fermented liquids, including beer, liquor, soda, vinegar, and a variety of ripening or rotting produce.
What Do They Eat?
Fruit flies mainly feed on the yeast that forms when fruits and vegetables start to decay. The insects also consume other decaying matter. Preferred food sources include fresh fruits and vegetables, such as tomatoes, bananas and grapes, as well as fermenting liquids, such as beer, cider, vinegar and wine. Adult fruit flies may land in spilled soda and sweet juices to feed as well.
Vs. Other Pests
Insects like mosquitoes, black flies, and some species of midges are commonly mistaken for fruit flies due to their small size. Not all these insects feed on blood, but all three are capable of biting humans. However, it is rare for these types of flies to infest homes.
Problems Caused by Fruit Flies
Damage to Food
Fruit flies cause irreparable damage to fruits and vegetables. When left unchecked in bars, restaurants, grocery stores and similar businesses, the presence of the pests may lead to the loss of products and profits.
Nuisance & Disease
Though sometimes regarded as a nuisance pest, the fruit fly can also carry certain disease-causing organisms from coming into contact with excrement, trash receptacles and dumpsters. In rare cases, humans and pets may ingest live larvae which can lead to myiasis and diarrhea.
Life Cycle & Reproduction
Fruit flies go through four stages in their growth process and you can kill fruit flies in any of these stages. However before you begin to get rid of fruit flies you may need to know what the stages are first.
Read more about the fruit fly life cycle.
How Long Can They Live?
Fruit flies enjoy a lifespan of about 40 or 50 days and have been known to lay up to 500 eggs during that time.
How Do You Find Them?
What Attracts Them?
The fruit fly often enters buildings from compost piles, dumpsters and trash receptacles where produce is disposed. Attracted to uncooked foods and the yeast produced by over-ripened fruits and vegetables, fruit fly infestations can rapidly get out of hand. The presence of quickly decomposing produce attracts the pests and sustains their larvae.
Where to Look For
- Check drains, garbage disposals, trash cans and food storage areas for any visible indications of fruit flies.
- Fruit flies generally appear around exposed produce in search of food and a site to lay their eggs.
- Look for maggots around rapidly rotting fruits and vegetables.
- Adult fruit flies are often found in glasses of wine or other attractive liquids left out overnight.
Houseplants may provide harborage to flies in the home, as well. Flies found living and breeding in houseplant soil are often mistaken as fruit flies, but in most cases the insects are fungus gnats. Similar in appearance to fruit flies, fungus gnats are slightly larger and darker in colour. These insects prefer damp soil over fermenting fruit for breeding and can be as much of a nuisance as fruit flies.
In the Garden
Fruit flies can be attracted to the ripening and fermenting fruits and vegetables in a homeowner’s garden. Common garden plants that fruit flies infest include tomatoes, squash, and melons. Female flies often lay their eggs just under the surface of fruits and vegetables so larvae may feed on their surroundings after hatching. Gardeners should be careful when bringing potted plants and picked harvests into the home, as overripe fruits and vegetables may contain fruit fly larvae that will hatch and infest the home.
Perhaps the best way to help eliminate fruit fly infestations is to remove anything that attracts the insects. Leaving produce unsupervised and uncovered invites the pests to feed and breed.
Here are some tips:
- Throw away wet trash frequently.
- Dump rotting fruits/vegetables or put them in the fridge.
- Look for any moisture in home plants.
- Check your drain for any food particles stuck in there.
- Thoroughly dry dish rags, wet mop etc frequently.
Maintaining proper sanitation of food preparation and storage areas remains critical to keeping fruit flies away. In restaurants and bars, cleaning hard-to-reach areas, such as behind refrigeration units and under stoves where food can collect will also help eliminate attractive breeding sites. Regularly emptying trash cans and recycling bins helps discourage fruit flies from infesting as well.
Tips for Removal from Home
Home remedies for capturing and eradicating fruit flies include trapping the insects in a jar filled with cider-vinegar or a similar substance, with a paper funnel serving as the lid. Chemicals and store-bought traps may also prove beneficial for smaller infestations. As the fruit fly is quick to reproduce, infestations can rapidly become uncontrollable.
Elimination Can be Tricky
Eliminating fruit flies can be much more of a challenge than preventing them: the only way to get rid of them is to remove or thoroughly clean every possible breeding site. Simply killing the flies that you can see doesn’t eliminate the eggs and the cycle will repeat itself over and over unless you are very thorough. Identifying the source of the new flies can be difficult, especially in an environment where there are a number of potential breeding sites.
Traps can locate and eliminate some fruit flies, but eliminating their development sites is the best control option. Typical development sites include garbage cans, under appliances, in fruit bowls and anywhere else that may harbor even a small bit of organic material.
Wait 1-2 weeks to determine if your efforts were successful. If they weren’t, the flies will reappear with the next hatching cycle and you will need to renew your efforts to identify where they are breeding and eliminate those sources.