Anyone who thinks mice or rats are the worst thing to have creeping around their house obviously has not encountered the specific horror of realizing bats are living in their home. Mice might squeak and rats might gnaw through walls, but bats do these things and then some. If they get into your walls you can hear them fluttering around; if one escapes into the light of your home you will have to face capturing and expelling a creature squeaking, hissing, and nose-diving at you. Their droppings accumulate rapidly under their roosting spot and are so toxic you will likely have to wear a respirator just to enter your own attic or garage.
The hard truth is bats are not easy to eliminate. If you research how to keep bats out of your house you will quickly understand this is a two step process: expelling the bat colony and then sealing up your house so that they cannot return. Killing off a bat colony is neither humane nor practical, so you will have to think of the process more as an eviction than an extermination. With a little diligence, and perhaps the help of a professional pest control expert, you can ensure the bats leave and do not return.
Assess Your Bat Situation
You will need to perform a basic inspection of where the bats are living. This is tricky because anywhere bats live you will find their poop, and bat guano is highly toxic. The experts recommend a HEPA filter mask, protective clothing, and goggles as the least amount of gear for confronting a bat problem. Bring a flashlight but try not to startle the bats with its light. See if you can determine how large the colony might be, where they are roosting, and even how they might be entering the house. If you can get a good enough look from a distance, you may be able to identify which variety of bat has moved in.
One of the surest ways to locate their entrypoint is to stand outside your home around dusk and wait for the bats to come flying out. Chances are they have multiple entrances and exits. Once feeding time begins, you should see bats swooping out of particular spots under the eaves of the roof or from between siding near their roosting place. Make a note of these locations so you can perform a close-up inspection of these holes and cracks during daylight hours. Alternatively, you can watch the bats re-entering the house before dawn.
Two things you or a pest control expert will need to look for during an inspection: the primary exit/entrance you noted and any cracks leading to your attic, garage, etc. as small as half an inch wide. Bats can squeeze in through holes that small and always have secondary entrances marked out in case their front door, so to speak, is blocked.
Sealing Your House
While it might be tempting, don’t seal off the bats’ primary entrance as soon as you find it– they will simply resort to one of their secondary entry points when it is time to feed. You also don’t want to risk sealing the bats into your house, which is a sure way to have them fluttering through your living space looking for a way out! Your first step is to seal off all holes and cracks serving as potential secondary routes for the bats. There are a lot of informational and commercial sites, like Bat Conservation and Management, that list the best caulks, foams, and sealants to use for bat problems.
You may notice once this step is complete the bats are only leaving from a single location each night or returning to a single place each morning. It may also take longer for them to leave to feed. This is a good sign, since it means traffic is backed up at the main hole and they are now unable to escape by other means. Once you are confident you or the professional you hire has sealed off these alternate exits/entrances, you are ready to seal up their primary exit.
Evicting the Bats
You now need to make sure every single bat has left the house to feed so you can seal up a bat-free attic or garage. Bats leave every night to feed except when they are caring for their young, in which case they take turns going out to eat. Make sure you are not trapping babysitting bats and their young by performing these steps well away from baby bat season during the summer months. This is why it is important to read more about the specific kind of bats living in your house.
How do you get bats to leave but make sure they can’t return while you’re sealing up the primary entrance? There are many commercial screens, funnels, and cones designed to freely let bats out but making it impossible for them to reenter after feeding. If you have a grasp on the habits of the colony in your house, you should have a good idea of when they are all gone to feed at night. You can either work in the dark to seal up the hole or trust the bat exclusion device will keep them out so you can perform the task the following day. Some experts recommend leaving the device up for several days while you continue to monitor the situation, ensuring you will not close any bats up inside.
Making Bats Your Neighbors
Some bat colonies are incredibly stubborn and homeowners go through all of these steps only to have the bats return. Some people hate to say goodbye to the insect control benefits a bat colony brings. In this case, you might have to accept that your property is especially welcoming for bats and set up an alternative living situation for them. Bat houses are one way to lure the bats away from your home, which you still need to seal up, and ensure they do not return. The Humane Society has great advice on how to maintain your local bat population but keep them well away from your living space.
Hopefully you are a little closer to evicting the bats from your house and reclaiming your living space. A bat problem is not the easiest pest issue to solve, but with a little know-how and diligence there is light at the end of the tunnel– and you know how bats feel about that.