Signs Bats Are Using a Structure
Bat activity is often quiet and easy to miss until the signs are unmistakable.
What to look for
- Small dark staining around a soffit, gable vent, or roofline gap (oil and dirt from repeated entry)
- Guano (droppings) accumulating on the ground, in the attic, or on a windowsill below an entry point
- A faint ammonia-like odor
- Squeaking or scratching near the roofline, most noticeable at dusk as bats leave to feed
A quick way to confirm it
Watch the suspected entry point at dusk for about 20 to 30 minutes. Bats leaving in a steady stream to feed is a clear confirmation.
Timing matters
Florida’s bat maternity season runs April 16 through August 14 each year. Under Florida Administrative Code 68A-9.010, it is illegal to exclude or evict bats from a structure during that window. Legal exclusion using one-way devices can only happen August 15 through April 15, and devices must stay up at least 4 consecutive nights with overnight lows forecast at 50°F or above.