Stable Fly

Stomoxys calcitrans

Stable Fly

Adult stable fly (Whitney Cranshaw, Colorado State University,

Stable Fly

Adult stable fly mouthparts (Pavel Krok, Wikimedia Commons)

Stable Fly

Stable fly life cycle (University of Nebraska)


  • 1/4 inch; gray
  • four dark stripes on top of thorax (similar to house fly)
  • mouth parts are long and straw-like for blood feeding

Nesting Habits

  • eggs may be laid on moist straw or decaying organic matter such as hay and grass clippings and chicken manure


  • larvae feed mostly on animal carcasses, garbage, and decaying organic material


  • can inflict painful bites
  • nuisance inside buildings; enter buildings from outside
  • can spread disease through contact

IPM Recommendations

  • Keep exterior doors closed, install screen doors, or install an automatic door closer, especially on doors leading into the kitchen.
  • Keep screens in good repair.
  • Improve sanitation.
  • Keep dumpsters at least 50 feet from the building.
  • Locate breeding susbstrate, if possible, and remove.
  • Keep trash cans, dumpsters and garbage areas clean and free of odor.
  • Close lids on dumpsters and garbage cans.
  • Exclude fly entry via caulking, weather stripping, door sweeps, screens, etc.
  • Properly place light traps to catch flies that come indoors.
  • Use a fly swatter.
  • If animals are raised on school-adjacent properties, consider discussing control options with owner.

Additional Resources

IPM for Flies: Integrated Pest Management in Sensitive Environments (University of Nebraska-Lincoln Extension)