Santa Barbara Museum of Natural History

I have some bats living in the wall of my garage.  I am replacing the siding on the garage and need to relocate them.  What is the best thing to do?  

Bruce, Mission Canyon - April 18, 2018

Curator Response

Hi Bruce,

Unfortunately, it’s not easy to relocate a bat colony. Before you do it, you may want to install a bat house in a suitable location on your property, so that evicted bats can quickly find an alternate roost. Find out what species of bat is roosting in the building. There are several sensitive species of bats that occur locally, and special care and planning is needed before attempting to relocate them. Even if your bats aren’t sensitive, knowing the species can help you inform your bat box design. Some species are crevice roosters, while others prefer small or large hollow spaces.

To exclude your bats, you’ll need to determine how the bats are getting into and out of the area of the wall where they are roosting. Exclusion barriers can then be installed over the access points. The barriers allow bats to leave, but not to return. Bat Conservation International has some very thoughtful advice about this: http://www.batcon.org/resources/for-specific-issues/bats-in-buildings/excluding-a-colony

The problem with undertaking relocation at this time of year is that bats are likely to have young which they leave in their roost site. So if you exclude adult bats from being able to reenter a roost site, you’re likely to cause the death of their young. I would recommend against attempting removal/exclusion of bats until the fall, or better yet, next winter. Many of the bats that occur in our region tend to migrate to more temperate environs further south for the winter.

Hope this helps!

Paul Collins, Curator of Vertebrate Zoology