Bats provide essential pest control and pollination services but are frequently excluded from buildings using methods that trap and kill them, raising welfare and conservation concerns.
Bat exclusion raises welfare concerns when conducted during the maternity season, typically May through August in the northern hemisphere. Pups that cannot fly are left inside when adults are excluded, dying of starvation. The welfare harm is compounded by the conservation impact on declining species. Responsible exclusion conducted outside maternity season using one-way devices allows bats to exit naturally and find alternative roosts without causing death of dependent young.