Bat Exclusion - NOT Extermination

Our human structures sometimes provide the perfect roosts for bats.  Well, perfect from the bats’ perspective; people don’t always think so.  However, there is no reason to exterminate the bats.  In fact, doing so is not only cruel but counterproductive; bats play a crucial role in controlling insect populations.  Instead, bats should be excluded from the building, allowing their exit but preventing their return.

Many bats like narrow slits for roosting sites.  If they lose their natural roosts in trees or caves, they might seek shelter in human structures.  Places like attic vents or gaps in old wooden siding often provide just the spacing that bats prefer.  Usually, there really isn’t any reason to evict bats.  If they are causing a problem, though, you might be able to exclude them yourself, or you can contact a reputable bat-exclusion professional who pledges to use safe and effective exclusion methods.

Bat exclusion has two main components: 1) leaving a one-way exit through which bats can leave but cannot return and 2) sealing all other potential entryways.  Bat Conservation International (BCI) has instructions on its website on how to use tubes or netting for one-way exits.  Other entry points can be sealed with caulking, flashing, screening, or heavy-duty mesh.  Please visit http://www.batcon.org/index.php/bats-a-people/bats-in-buildings/subcategory/69.html for more details.

Whether you are excluding bats yourself or hiring a professional, it is imperative not to do the excluding during maternity season, when bats give birth and raise their young.  If exclusion is done before baby bats can fly, the young bats can be trapped inside the structure and starve to death.  Maternity season in North America begins as early as mid-April in the southernmost U.S. and in mid-June in the northern U.S. and Canada.  Young bats fly by late August.  Therefore, exclusions should not be performed between April and August.

When bats are excluded, it’s a good idea to install bat houses for alternate living quarters.  BCI has information on building or buying bat houses at http://www.batcon.org/index.php/get-involved/install-a-bat-house.html.

My church, Monticello Presbyterian Church, was founded in 1829, and the oldest part of the current structure was built in 1898.  Several years ago we discovered bats in the attic.  Unfortunately, they couldn’t stay.  I happened to be serving as an elder at the time, and I explained to the church session (governing body) the importance of bats and that we should exclude them, not exterminate them.  Thankfully, they agreed, and we hired a professional bat exclusion company.  The company humanely excluded the bats, cleaned up all the guano (bat droppings), and sealed the crevices in the wooden siding so that the bats couldn’t get back inside.  I’m happy that we did what we could to be the good stewards of creation that God calls us to be.