Fruit Flies

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Fruit flies get their name because they are often found feeding on ripening or decaying fruits and vegetables. However, they also are often found in garbage cans and other unsanitary locations.

HOW DO I KNOW IF I HAVE FRUIT FLIES?

  • Fruit flies are tiny flies that are often seen in the kitchen near bowls of fruit or vegetables, glasses of wine, dirty mops or brooms, and garbage cans.

  • Adult fruit flies sit on walls and around window and door sills as well as near their breeding sources.

  • Outdoors, fruit flies congregate nearby dumpsters, garbage cans or in damp compost piles where fruits and vegetables are discarded.

  • Fruit flies can be a problem year round, but are especially common during late summer and fall because they are attracted to ripened or fermenting fruits and vegetables.

WHAT DO FRUIT FLIES LOOK LIKE?

  • Adult red-eyed fruit flies are small flies about 1/8” in length with large, red eyes.

  • Adult dark-eyed fruit flies are a little larger than red-eyed fruit flies and have dark eyes.

  • Fruit flies have beige bodies with transverse black rings across their abdomen.

  • Fruit fly larvae are yellowish white, small, legless and pointed at the head end with inconspicuous head.

ARE FRUIT FLIES DANGEROUS?

  • Fruit flies do not bite, however fruit flies are considered to be a hazard to human health because their hairy bodies and sticky feet can transmit harmful germs and bacteria.
  • Fruit flies are known to spread diarrhea-causing illnesses.
  • Adam’s recommends that you do not use your hands to kill fruit flies, but if you do, to wash your hands afterwards.

WHY ARE FRUIT FLIES IN MY HOUSE?

  • Unrefrigerated fruits and vegetables in a bowl on your kitchen counter, in the display case at your favorite grocery store, or even still on the vine in your garden, will attract fruit flies.

  • Fruit flies can smell ripe and fermenting fruits and vegetables from as far as 3/4 of a mile away.

  • Fruit flies can get inside your house through window screens or crack and crevices around windows and doors.

  • Sometimes, fruit flies -- or their eggs – can get into your home on fresh fruits or vegetables you brought home from the grocery store.

  • Harvesting vine ripe tomatoes and other vegetables from your garden may also be how fruit fly eggs are getting inside your home.

  • Although fruit flies are attracted to ripened or fermenting fruits and vegetables, they will breed in drains and wherever there is moist organic matter.

  • Adult fruit fly adults can easily follow air currents, so there could be several breeding places inside your home.

  • Fruit flies are a nuisance year round, especially where sanitation is an issue.

WHAT DO FRUIT FLIES EAT?

  • Adult fruit flies prefer to eat overripe, fermenting fruits and vegetables, plant secretions and honeydew produced by aphids.

  • Fruit flies also feed on the skins and stems of fruit, fungi, and the sludge left in drain pipes.

  • Fruit fly larvae also feed on fermenting and decaying fruit and vegetable matter dripped under your refrigerator or caught in a sponge.

WHAT IS THE LIFECYCLE OF FRUIT FLIES?

  • Fruit flies go through a complete metamorphosis, which has four stages: egg, larva, pupa and adult.
  • Fruit flies multiply quickly: at 70°F the life cycle can be completed in two weeks; and at 85°F it is completed in only 8 days.
  • A mated female will lay approximately 500 eggs in her lifetime.
  • Eggs hatch in 24 hours and go through three larval instars within four to six days.
  • Puparium (the hardened exoskeleton of the last larval instar) and pupa stage lasts five to six days.
  • Newly emerged flies are attracted to light.
  • After 48 hours, new adult fruit flies become sexually active; and the cycle repeats.

13 INTERESTING FACTS ABOUT FRUIT FLIES:

  1. There are over 4,500 species of fruit flies in the world.
  2. The genus Drosophila includes a large number of species of fruit flies, including the Drosophila melanogaster which is considered the most common species of fruit flies found inside buildings.
  3. Fruit flies can be found all over the world, except in Antarctica.
  4. Male fruit flies that are sexually rejected by female fruit flies find consolation in alcohol. Researchers from the University of California proved that male fruit flies prefer alcohol to non-alcohol food after they’ve been rejected by female fruit flies. After rejection, a chemical in the fruit fly’s brain known as neuropeptide F decreases, creating an urge for alcohol just like in humans in similar situations.
  5. Because fruit flies breed easily and quickly, they are the most commonly used insects to study genetic traits and chromosome mapping. The fruit flies’ short lifespan enables scientists to examine changes and mutations that can occur between birth and death.
  6. About 75% of human diseases that are linked to genetic abnormalities can be induced and examined in fruit flies. Fruit flies are used in the study of Parkinson's and Alzheimer's disease, aging, cancer, immunity, alcohol and drug abuse.
  7. Fruit flies can beat their wings 220 times per second.
  8. Fruit flies are excellent fliers. They are able to execute sharp turns and rotate their bodies 90 degrees in just 50 milliseconds.
  9. Each of a fruit fly’s eyes consists of 760 individual lenses.
  10. Two-thirds of a fruit fly's brain is used for seeing.
  11. In order to attract the opposite sex, a male fruit fly will vibrate his wings in such a way as to produce songs, changes the posture of his body, and will even lick the female's body to get her ready to mate.
  12. A female fruit fly will often mate with more than one male and then collect the sperm cells inside her body.
  13. FDA regulations allow 35 fruit fly eggs per 8 oz. of raisins (FDA: Defect Levels Handbook).