BAT EXCLUSION TECHNIQUE

As their natural habitats are destroyed, bats often move into the attics, eaves, or walls of houses and other buildings. Unless the numbers of bats are very large, most homeowners are unaware that bats are using their home as a day or night roost.

If for some reason you prefer not to share your home with bats, they can be humanely evicted during the early spring and late fall. They must never be evicted during nursery season—early May through September—because the babies will be unable to fly away with their mothers. In addition, never attempt to poison bats, as this practice is illegal in California and most other states.

To humanely evict a colony of bats, hang netting over suspected entry locations. Possible entry locations are illustrated here:



The netting should be fastened on the top and both sides of the point of entry, but left open at the bottom, with the bottom edge hanging approximately 12 inches lower than the entry location. This will create a form of "doggy door," from which bats will be able to crawl out from under, but to which they will not easily gain readmittance. One-quarter-inch bird netting or fiberglass screening are both suitable as netting material. Leave netting in place for at least one week to be sure that all bats have left, then permanently seal the entry hole.