What's Buzzing Around the Bananas?

Vinegar flies, sometimes inaccurately called fruit flies, are small flies found hovering around over-ripened bananas left out on the counter.
What's Buzzing Around the Bananas? - Articles
What's Buzzing Around the Bananas?

These light yellowish brown to dark brown colored flies lay eggs in the fermenting materials. The complete life cycle of vinegar flies (egg, maggot, pupa, adult fly) can take place in as little as eight days if the conditions are right, which can quickly lead to large populations. While vinegar flies don't bite humans, they are a nuisance to have inside a building and should be controlled using integrated pest management (IPM) tactics.

Step 1: Removal of attractants

  • Remove any over-ripened or rotting fruit and vegetables.
  • Cover the fruit bowl or place fruits and vegetables in the refrigerator.
  • Don't toss food garbage into waste-paper baskets.
  • Keep compost in a covered container and take out daily. Clean container afterward.
  • Use a 16-mesh screening (or smaller) in doors and windows. Make sure there are no holes or gaps.

Step 2: Sanitation

  • Clean counters, floors, drains, garbage cans, recycling and compost containers, etc. regularly. Clean, clean, clean!
  • Store trash in a covered container. Don't reuse trash bags.
  • Rinse bottles and other items before placing in a recycling bin.
  • After mopping, dump out the mop water and clean the bucket and mop head.

Step 3: Trapping

Make your own trap:

  • Pour apple cider vinegar into a jar until it's around ΒΌ inch deep. Add one or two drops of liquid dish soap to the vinegar and mix them together.
  • Make a paper funnel, hold it together with tape. The opening at the bottom of the funnel should be around 1/8 inch in diameter. The opening at the top of the funnel should be larger than the top of the jar.
  • Place the funnel in the jar and make sure there aren't any gaps around the edge where the funnel and jar meet. Again, you can use tape to seal any gaps.
  • Put the trap near the source of the flies. The apple cider vinegar attracts them, and they fly into the funnel. With only a small opening, it's difficult to escape once in the jar. The flies drown when they land in the vinegar because the dish soap breaks the surface tension.
  • Empty the trap and reuse if necessary.

Step 4: Evaluation

  • Evaluate the results of using IPM. If the flies are gone, continue doing what you are doing and monitor for problems. If there are still flies, look for other possible breeding sites. Talk with the pest control professional at your facility for more IPM solutions.

For more information, see the Penn State Extension publication Vinegar Flies.