Bats In Buildings
In the United States and around the world, bats provide humans many beneficial services by eating insects, pollinating flowers, and spreading seeds. In fact, no other order of mammals provides the ecological and economic services that bats do on a daily basis. Insect eating bats are the primary predator of night flying insects, many of which are mosquitoes and agricultural pests. A 2011 USGS study, found that bats save U.S. farmers $3.7-$53bn per year by reducing the need for pesticides. Every year pesticide use increases, threatening waterways and beneficial insects whose populations are already in drastic decline.
As much as we love our flying friends, sometimes they live a bit close for comfort - in our homes and businesses. Occasionally bats occupy buildings to hibernate, raise their young, or roost. These “alternative roosts” become occupied when their natural habitat is destroyed or disturbed. Many species in the U.S. will take residence in bridges, culverts, and buildings. However, it is much safer for bats and humans if they live separately.
How Do I Know If I Have Bats?
You will see, hear, or smell them. Areas where bats enter are typically stained brown due to body oils. Look around for guano (poop) as well, which accumulates under their roost sites. Bats are CHATTY!! They talk and gossip all the time. Their vocalizations are easily audible to humans although we can’t hear their echolocation calls. As for smell, a substantial colony will be a bit odorous, to say the least.
How Did They Get In?
Bats don’t need much room to access a building. An opening ½”x1” provides ample room for bats to gain access. Occasionally bats will enter open doors and windows. If a single bat is in your house, simply close it in one room and open a window, it should find its way out. It’s amazing how bats are able to find such unique roosting areas. What we’re curious about is how they inform the rest of the colony?? Such interesting animals!
A bat exclusion is a process that is used to lock bats out of a building. Bat exclusions are humane and do not harm the bat colony. One of the first steps is to determine if it is the proper time of year. Here in Florida, It is illegal to exclude bats from April 15-August 15 due to maternity season. This is when females are raising pups that can't fly. Maternity season varies depending on the part of the country which you live. Generally, maternity season falls during mid April - mid September. However, this time is too broad for specific regions of the country. An honorable professional can advise the proper time for their service area based on historic information.
After the presence of bats has been confirmed, the next step is to locate the active entry points that the bats are using. For these locations, a one-way door device is placed over the entrance which allows the bats to leave safely but not return. The entire colony will not leave in one night, and the exclusion material/device must be kept in place for multiple days. However, once they exit, they will search the home to attempt to get back inside. It is amazing how persistent bats can be to return to their homes. For this reason, it is important to hire a professional with experience in bat removal. Often, it takes years of practice for a professional to hone their skills. The one-way doors should be removed after an extended period of time has passed to allow all bats to exit. Once the doors are removed, the entrance can be properly sealed to prevent the bats from entering in the future. One-way doors should never be a permanent fixture on your home, because it is weaker than a true repair.
BTW, Bats Are Protected!
Bats are federally protected in the U.S. Check out the resources below.
Environmental Protection Agency, Section 24(c) of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), which prohibits off-label use of pesticides. Bats are protected in that no chemicals are labeled for use against bats.
The Endangered Species Act of the U.S. Fish and Wildlife Service offers some protection to bats deemed federally endangered (In the United States and Canada, eight species or subspecies are listed as Endangered, a ninth is listed as Threatened as of February 2017). See https://www.fws.gov/endangered/laws-policies/ for U.S. federal policy governing endangered species. More info here.
If you have bats in your home, the following resources can help. Check Out These Professional Bat Exclusion Companies. These businesses have a history of contributing to bat conservation efforts. Consider contacting them for your bat removal needs.
Michigan - Critter Catchers, Inc.
United States: Wildlife Control Helpline, LLC