The big brown bat accounts for over 75 percent of the bat contacts with people and pets and is the bat most often tested for rabies. The little brown bat is also quite common in homes during the spring and summer, and large numbers hibernate in abandoned iron mines. However, the number of human and animal exposures, and the number of little brown bats found to be rabid, are much less than for the big brown bat. The only permanent method to get rid of bats from a home and keep them out is to exclude them by bat-proofing. There are no chemicals registered in New Jersey for killing bats, and the use of unregistered pesticides only increases the chances that children and pets will come in contact with sick bats.
Bats often roost in dark, undisturbed areas, such as attics and wall spaces.
The entry points are often near the roof edge, such as under the eaves, soffits or loose boards, openings in the roof or vents, or crevices around the chimney. Sometimes bats will roost behind shutters or under boards without entering the home. While the objective is to seal off all of the actual and potential bat entry points, care must be taken to follow the correct procedures to avoid blocking the bats inside the roost. Sometimes the only evidence of the presence of bats in a building will be an accumulation of droppings in one area of the attic, or droppings and rub marks on siding at the bat entry opening. This allows the bats to leave but not enter again.