Bat Encounters

Occasionally a solitary bat will fly into a garage, home, or other building. Most often in these cases direct contact can be avoided.

1. First, close interior doors to prevent the bat from flying further into the building. Then open windows and doors that lead outside and turn off all lights and ceiling fans. The bat can usually find an exit and escape on its own.
2. If the bat does not leave on its own, it can be safely captured and released in the spring/summer/fall. Remember bats are rarely aggressive but like all wild animals, may bite when frightened.
3. Always wear thick gloves if potentially capturing or handling bats. When the bat lands, cover it with a small container with air holes. Slip a piece of cardboard between the wall and the container, trapping the bat inside.
4. Put the covered container with bat somewhere quiet until nightfall then take it outdoors for release. Do not attempt to give food or water to the bat.
   Many bats cannot take flight from the ground. You can hold the container up, slowly remove the lid, while tilting the container. The bat will likely fly out, if not hold the container high off the ground. If the bat seems unable to fly, monitor it and call the Ministry of Environment Inquiry Centre.

If you find a bat in your home in the winter, it is a bat that has roused from hibernation and is most likely a big brown bat. Big brown bats hibernate in a variety of structures in the winter, including caves, mines, rock crevices, and buildings. Unfortunately, if you release a bat back outside (or use exclusion devices) in the winter and it can no longer access its roost (in your home or nearby) and it will most likely freeze or starve to death. In this case it is best to call the Ministry of Environment Inquiry Centre.

If necessary, minimally invasive action to seal off potential access points for bats to the living space of your home can be taken at any time without special authorization. Hibernating bats are extremely difficult if not impossible to locate inside an attic or walls during the winter. It is more effective to exclude bats in the spring when steps can be taken to prevent them from re-entering the home. In the spring building owners can choose to install one way exits and permanently seal exterior access points, per the Bat Exclusion Policy. This exclusion method works with the biology of bats and minimizes renovation costs for the homeowner.

Like finding a single bat in the winter, hearing or seeing many bats in the winter means it is likely you have located a hibernating colony. Note that sometimes things that sound like bats can turn out to be other things (e.g. mice or squirrels). First, try not to disturb these bats. Bats go into a state of torpor in the winter and disturbing them can cause stress that may affect their ability to preserve energy stores through the colder months.

Sealing human living quarters off from attics and crawl spaces can allow bats to continue to persist through winter while keeping humans safe. There are minimal health risks of having bats in the walls/attics if they are not directly in contact with people. You can find information on potential health risks from the Canadian Wildlife Health Cooperative on Bats and Rabies and Histoplasmosis.

If you find many bats in a building in the summer, you likely have a maternity colony. This can be big brown bats or the Endangered little brown bat – and they often return to the same place year after year.

A maternity colony is where females give birth, nurse, and wean their young. Installing exclusion devices can be safe before pups are born. Once the babies arrive (June to August, depending on conditions and species), they cannot fly for up to five weeks, so it's best not to disturb the bats until the pups are mature enough to fly. If you decide to install exclusions, consider putting up a bat house first.