Fruit fly.

Facts About Small Flies

Depending on the types of flies that are present, different actions may be required for treatment and elimination. Understanding some of the more common types of small flies and their preferred breeding sites can help with fly prevention in your facility. 

facts about small flies


Fruit/Vinegar Fly

  • Adult is about 3-4mm, dull tan to brownish yellow or brownish black with red eyes.
  • Attracted to fruit for egg-laying; feeds on the fluids in fermenting fruits and vegetables.
  • Breeding sites: unrinsed bottles and cans, indoor and outdoor trash receptacles, used mops and rags, beverage dispensers, open foods, standing water, floor mats, drains, garbage disposals, damp laundry (e.g., linens)
  • Capable of breeding indoors and well as outdoors


Image of a moth fly.

Moth/Drain/Filter/Sewage Fly

  • It is 1,5-5mm long and pale yellow to brownish gray to blackish.
  • Adult has a delicate fuzzy appearance and flies only short distances, then crawls on surfaces.
  • Breeds indoors and outdoors on gelatinous bacterial film of drains, filters, sewers, lift stations, pits and sump pumps.
Image of Phorid Fly

Phorid Flies

  • Adult is 1-5mm long and is black, brown or yellowish.
  • Has a humpbacked profile and erratic movements, particularly when running.
  • Breeds indoors and outdoors in moist, decaying matter; may be a sign of a plumbing or structural problem.

More Resources

Fruit flies on an orange.

Small Flies and Food Safety

Although the fruit fly (also known as a small fly) has historically been considered a nuisance pest, recent research proves that small flies contaminate food with bacteria carried from unsanitary surfaces (such as trash, drains, mops, etc.). 

People out to eat sitting around a table.

Small Flies and Customer Experience

You’re enjoying a meal with friends at a restaurant and mid-sentence, you notice a fruit fly buzzing around in front of you. While you probably find this to be a nuisance, did you know it is also a sign of sanitation issues in the restaurant? 

Small flies on fruit.

Fly Control and Prevention

There are many simple actions that can make a big difference in avoiding a fruit fly infestation.