What’s that squeak? That rustle of wings? That shadow moving across the ceiling?
Bats are one of the most common home invaders around the world, and while they’re usually harmless, they’re certainly not welcome — and for good reason. When bats roost in homes — usually in attics and other dry, warm places — they create a mess of droppings and pee that emits an unpleasant aroma. And if they manage to get into the living area of a home, there’s a concern they could carry rabies, a viral disease that can be transmitted to humans through a bite.
So if you do find a bat or several in your home, what’s the best plan of action?
One option is to call a professional, a pest-removal specialist who can evict the bats safely, efficiently and effectively. The other option is to get rid of the critters yourself.
Calling in the professionals
“Some people might not know all the tricks,” said Shane Steeves of Midcoast Wildlife Specialists, a company that has been evicting bats and repairing the damage they leave behind since 1998. “They may end up locking them into the home instead of finding the right opening and locking them out.”
Just this year, Midcoast Wildlife Specialists has removed bats from about 150 homes throughout the state of Maine, with the typical eviction costing between $1,200 and $1,500 and an additional cost for any cleanup or repairs.
“We’re one of the few companies that will do the whole thing, the exclusion part and the cleanup and repair,” Steeves said. “We’ll often remove all the old insulation, vacuum and sterilize and re-insulate back to state code.”
Bat infestations can be messy and unsanitary. But before any cleanup can be done, the bats have to be excluded from the building — for good.
To evict the bats, Midcoast Wildlife Specialists locates where the bats are entering the house. They then create a one-way door over the entry point. This simple contraption opens outward, allowing the bats out of the house, but not back in. They then wait for the bats to fly out for their nightly hunt.
However, Steeves and his associates prefer to only remove bats from buildings during certain times of year, when the animals are most likely to survive the ordeal. In Maine, they usually won’t evict bats when they’re raising pups in late spring and early summer or while they’re hibernating in late fall and the winter.
“They may not survive,” Steeves said. “They may not find another dwelling in time to take up occupancy. If it gets too cold, they actually freeze to death.”
But sometimes, they will make an exception.
“If [the bats are] a threat to the person or a very bad health issue, we unfortunately take a hit and we do the work,” said Steeves, who consults with a state biologist in such cases. “We let [the biologists] make the call.”
Getting rid of bats yourself
Bats play an important role in the ecosystem around the world by consuming vast quantities of insects, pollinating plants and dispersing seeds. And of the more than 1,300 species of bats living worldwide, many species are endangered or threatened. Therefore, it’s a good idea to consult a local wildlife specialist such as a game warden before taking bat-related matters into your own hands.
If you do decide to remove bats from your home without the help of professional services, a great resource to learning more about this is Bat Conservation International, a worldwide organization dedicated to the protection of all bat species and the goal of “creating a world in which bats and humans successfully coexist.” On the organization’s website, batcon.org, there are detailed instructions on how to build a bat exclusion device out of a PVC pipe that acts as a one-way door.
“[But] first you have to figure out how they’re getting in,” Fran Hutchins, Bat Conservation International’s Director of Bracken Cave Preserve in Texas, said. “There’s usually a little crack or hole the size of a quarter. That’s all they need to get into a space.”
Hutchins said that bats often enter a home through the eves or gables, and that they can work their way through broken vents and screens. Often they’ll leave behind grayish “scuff marks,” where their body oils rub off as they squeeze through the narrow space.
“A lot of bats like to roost in nooks and crannies, caves and hollows in trees,” Hutchins said. “They like a very hot roost, so many times, they’re in someone’s attic space for that reason. It’s a nice, warm, dry, dark place to be.”
When a bat starts to roost in a house, the main concern, Hutchins said, is the mess and odor they cause, but there’s also a concern about bats carrying and transmitting rabies.
Most bats don’t have rabies. For example, among bats submitted for rabies testing because they could be captured, only about 6 percent had rabies, according to the U.S. Centers for Disease Control and Prevention. Nevertheless, bats are the most common source of human rabies in the U.S. Among the 19 naturally acquired cases of rabies in humans in the country from 1997 to 2006, 17 were associated with bats. Among these, 14 patients had known encounters with bats. Four people awoke because a bat landed on them and one person awoke because a bat bit him. In these cases, the bat was inside the home.
Rabies is transmitted to humans through the saliva of infected animals. Therefore, it’s important that anyone dealing with bats wear gloves. Though if you use an exclusion device to remove the bats, you won’t need to come in contact with them at all.
“You also could put up a bat house beforehand, and then maybe they’ll move to the bat house rather than another part of your house or the neighbors,” Hutchins said.
However, in cold climates, bat houses are not warm enough dwellings for bats during the winter. If you can, it’s best to wait until spring.