Signs You Have a Bat Infestation and How to Safely Remove Them

HWCS Expert Team

Bats are fascinating creatures that play a vital role in insect control, eating thousands of mosquitoes and pests every night. However, when they decide to roost in your attic, walls, or chimney, they become a serious liability. Bat colonies can grow quickly, and the accumulation of their waste (guano) poses significant health risks.

Recognizing a Bat Problem

Bats are nocturnal and stealthy, so you might not see them right away. Look for these clues:

  • Guano Piles: Bat droppings look like mouse droppings but are shiny and crumble into dust when touched (due to insect parts). You might find piles on your porch, attic floor, or directly under the entry point on the side of your house.
  • Staining: Bats have oils on their fur. Over time, the entry points they squeeze through will develop dark, greasy rub marks.
  • Smell: A large colony produces a lot of waste. A strong, ammonia-like odor coming from the attic or walls is a telltale sign of accumulated guano and urine.
  • Squeaking: You may hear high-pitched squeaking or scratching sounds inside walls, especially at dusk and dawn when they are waking up or returning to roost.
  • Visual Confirmation: Watching your roofline at dusk (sunset) is the best way to confirm. If you see bats swooping out from your eaves or vents, you have a colony.

The Health Risks of Bats in Homes

While bats are not aggressive, living with them is dangerous primarily due to Histoplasmosis. This is a respiratory disease caused by a fungus that grows on bat guano. When the guano dries and is disturbed, spores are released into the air. If inhaled, these spores can cause serious lung infections.

Additionally, bats are a vector for rabies. While less than 1% of bats carry rabies, any bat found inside the living space of a home is a cause for concern and potential testing.

Why You Can’t “Trap” Bats

You cannot simply trap bats and move them. It is ineffective because they have a strong homing instinct and will return. Furthermore, in many places, it is illegal to kill bats or trap them during maternity season.

Most bat species in the US are protected by federal and state laws. During maternity season (typically late spring to late summer), flightless baby bats (pups) are in the roost. If you block the mother out, the pups will starve and die. This is inhumane, illegal, and results in a rotting smell in your walls.

The Only Solution: Exclusion

The only legal and effective way to get rid of bats is through a process called exclusion.

  1. Identification: Professionals identify the species and the main entry points.
  2. Sealing Secondary Points: All potential entry gaps except the main active ones are sealed tightly.
  3. Installing One-Way Valves: We install specialized one-way devices (often called bat cones or tubes) over the active holes. These allow bats to fly out at night to feed but are designed so they cannot fly back in.
  4. The Waiting Period: The devices are left in place for several days to ensuring all bats have left.
  5. Final Seal: Once the colony is gone, the one-way valves are removed, and the final holes are permanently sealed.
  6. Cleanup: Professional removal of guano and sanitization of the area is crucial to remove fungal spores and odors.

Bat exclusion is a precise science. Missing a single half-inch gap can lead to failure. If you suspect bats in your home, contact HWCS immediately for a legal, safe, and permanent solution.