Bats cannot survive in the winter without assistance. If you find a bat in winter (inside or outside), please contact a wildlife rehabilitator as soon as possible.
If you find a bat inside your home during other seasons, it can be excluded safely by following the instructions below:
Night: Segregate the bat in one room/area. Open doors and windows to the outside and turn ON all outside lights. Darken the room the bat is in by turning off all inside lights. Bats are attracted to outside lights where insects are often flying (food) and will exit your room to approach the light. Continue to watch the exits to ensure the bat has left.
Day: If possible, do not take your eyes off him/her, as bats are very small once wings are folded and can disappear quickly. Prepare a tupperware container, such as a large yogurt or ice-cream container, by poking holes in the lid. Wait until the bat has landed and put the container over the bat. Slip a piece of cardboard along the opening (from bottom to top in order not to break its little toes). Slide the bat to the bottom by upending the container. Put a small cloth into the container with the bat and close the perforated lid. Keep in a cool, quiet and protected area until dark. Take the bat outside, open the container and slide the bat out onto a surface at least six feet from the ground. The bat will fly away once it has warmed its body temperature through shivering (about five minutes). If the bat does not fly away in the next hour or so, it is advisable to recapture him/her with your container, and call a wildlife rehabilitator near you.
Important note: Bats can carry the rabies virus. It is advisable never to handle a bat barehanded. If you are bitten, or suspect someone in your household has been bitten, please contact your doctor right away.