What is the most important method for excluding bats from reentering structures?

The most important method for excluding bats from reentering structures is denial of reentry. This approach focuses on sealing potential entry points through which bats might access the building, ensuring that once they have been evicted, they cannot return. Effective exclusion involves thorough inspections to identify and seal any gaps, cracks, or holes, particularly in areas like attics, eaves, and vents where bats commonly enter.

When bats are excluded properly, it minimizes the chances of future infestations, making it a sustainable long-term solution. This method is more effective than simply trapping bats, which does not prevent further reentry and may also be stressful and harmful to the bats. The use of repellents can be less reliable, as their effectiveness varies and they do not physically prevent reentry. Similarly, using lights can discourage bats temporarily, but it does not address the structural entry points that need to be blocked for lasting exclusion. Thus, sealing the building and denying bats access is the most reliable method for keeping these animals out.