Bats Inside? How To Detect Bats

Are bats inside your home or building?  How do you detect bats?

You’ve called us.  You think you have bats inside, but either have only occasionally seen some, or not yet seen them at all.  Maybe you’ve seen some droppings, (please look in our “Common Questions” tab for info about how to determine the difference between a mouse dropping from bat guano, and how to detect if it is fresh or old) or maybe you’ve heard some little chirpy noises in the ceiling or wall. Could it be bats inside?

With over two decades in the bat business, we will know how to tell whether you have bats inside or not, and also where they are entering or exiting.  But, if there is any doubt, or if you are curious, you can do a little detective work yourself.  Go around the exterior of your home or building.  Look for guano on the ground, or on decks and porches, perhaps stuck on windows.  Or there may be some white urine staining on the siding or windows.  Then you can serve some “Watchman Duty”.  Stand at different ends of your house outside around sunset.  It helps if more than one person does this, but if it is just you, then circle around.  The difficultly is, it depends on what species of bats you may be hosting as to what time he is going to make his nightly exit.

Western Pipistrelle bats and the slow flying Silver-haired bats make their exit before sunset.  Mexican Free-tailed bats exit right at sunset, and usually in a nice column or group.  Our very popular Little Brown bats exits at late dusk.  The Big Brown bats makes their debut about 20 minutes after sunset.  The little California Myotis bat, the Townsend’s Big-eared bat and the cute and creamy Pallid bat leave about an hour after sunset.  The Pallid bat will continue to go in and out through the night.  Fringe-tailed bats leave 1 – 2 hours after sunset; the huge Western Mastiff bat waits for complete darkness.  And the mostly solitary guy, the Hoary bat leaves very late, 2 – 5 hours after sunset. He can make audible chattering and hissing sounds, and may like to hunt around your outdoor light.

If you prefer, you can also get out right around dawn in the morning and catch some erratic flying guests coming in for a landing and back to bed.  Now you know if there are bats inside and how to detect bats.