Types of Bat Colonies and Dangers of Bats

Bats in homes causing concern usually fall into three types.

Random bat – Random bats can be bats that enter through open doors, windows, garage doors, etc. This type of entry is impossible to protect against and most often occurs during the month of August when young bats start flying but can happen year-round.

Non-maternal colonizing bats – This situation is very common throughout the eastern region of the United States and occurs year-round, but most commonly during the months of October through February. Typically composed of male bats, this type of colony is generally a lesser number of bats than a maternal colony. They become a problem to home owners when a roosting colony overwinters in attics and void areas of a home. A warm spell or a drop in temperature during this hibernation period will awaken bats to find a temperature zone to fit their needs resulting in bats in interior of home. This type of bat situation is ended through exclusion.

Maternal colony – This situation is a female grouping of bats using attic or voids as an area to give birth and raise young. This colonization is often the most extreme and becomes generational as female bats born in a structure can return to said structure to give birth. During certain periods of this birthing cycle a “blackout” period will be followed. Blackout is the time period when bat pups have been born but are flightless. During this time frame bats cannot be evicted; however secondary work can be performed. This situation is ended through exclusion.

Bat exclusion is the process of ridding a structure of bats. Bats enter a structure through construction gaps and other areas common in the construction of our homes/structures. They are not rodents and do not gnaw into homes, but like a small rodent, can enter through gaps as small as 5/8 x 3/4-inch gap.

Exclusion must be done to the entire home as doing only one section would be akin to locking the front door while leaving the back door open. Bats have a homing instinct and strive to continue to roost in the same structure. Exclusion effectively ends bats ability to enter a structure leaving them no “choice” but to roost elsewhere.

Exclusion is the proven method of bat control and is approved by the National Wildlife Control Operators Association (NWCOA) and bat protection organizations. Exclusion is a long-term solution to a colony of bats using a home and reduces risk of a single bat entering interior of home. However, no professional in the wildlife control industry can guarantee a single bat will not enter your home due to factors beyond our control such as open garage doors/windows, furnace or fireplace venting that cannot be excluded due to venting issues.

If you encounter a bat in your home, it is a good idea to call a professional Wildlife Control Operator (WCO). Bats carry rabies, a disease which is fatal if contracted and treatment is not sought prior to the onset of symptoms. if you are bitten by a bat, or if saliva from a bat gets into your eyes, nose or mouth, seek medical attention immediately. Whenever possible, the bat should be captured, preferably by a professional WCO, and sent to a laboratory for testing. In addition, bats that are found in a room with a person who cannot reliably rule out physical contact (for example a sleeping person, a child, a mentally disabled person or an intoxicated person) will need to be tested for rabies. If contact has occurred or is suspected call your personal physician or local health department immediately.