Overview
- Health and identity: Authorities identify the tiny summer kitchen insects as Drosophilidae (commonly called vinegar, essig or Tau flies) and not the larger Tephritidae that damage orchards.
- Why they appear: These flies are drawn to fermenting or overripe foods and vinegar- or alcohol-like odors because they seek feeding spots and places to lay eggs.
- Risk and spoilage: Experts say the flies and their eggs are not known to transmit disease but can introduce yeasts and bacteria that accelerate food spoilage.
- Reproduction limits: A single female can lay up to about 400 eggs, development is fastest around 20–25°C, and reproduction falls off below about 10°C or above about 32°C.
- Practical control: Authorities recommend removing breeding sites by refrigerating or sealing food, emptying and cleaning compost and bins daily, and using simple traps of apple cider vinegar or fruit juice with a drop of dish soap.