Fall Is Coming: Are Bats Looking at Your Home?

As we approach fall, bats begin looking for a place to call home—and it could be yours.

As the crisper air moves in, their food source (insects) is on the way out. This is typically around October and November in New England and marks the time when bats begin preparing for hibernation.

Where Do Bats Hibernate?

Bats favor dark and secluded places for hibernation, which is why colonies are often found in caverns or other remote areas. However, bats can also hibernate much closer to you… as in your home.

While some bats seek out hollow trees or empty outbuildings, attics and crawl spaces present some of the most welcoming environments for bats seeking a winter spot. They love areas adjacent to warm vents and pipes, as the heat allows maternity colonies to focus less on staying warm and more on growing. Once they find these spaces in late summer or early fall, they often simply decide to stay through winter.

How to Tell If You Are Sharing Your Space with Bats

Other than the obvious sighting, you can inspect your attic for roosts in small cracks along attic walls. Roosts are often found between rafters or tucked into spaces between rafters and roofing materials. If you notice these signs, it’s time to call in the professionals.

Any bats present that aren’t in hibernation mode will most likely retreat rather than engage with you, but proceed with caution. Even if you don’t see evidence of a colony, wild animals can be unpredictable. Listen for squeaking or scurrying sounds and look for bat droppings (guano).

While mouse droppings and bat droppings are similar in appearance—black, dry, and about the size of a grain of rice—bat droppings are typically concentrated directly beneath the roost area.

Bat Hibernation: How It Works

Some bats are capable of limited activity during their hibernation period, but most remain inactive.

When a bat hibernates, its metabolism slows dramatically to conserve energy. Each day, the bat cycles in and out of a deep resting state known as torpor. During this time, a bat’s heartbeat can decrease from 200–300 beats per minute to as few as 10 beats per minute. This allows the bat to conserve energy and survive for up to six months on stored body fat.

Often, bats can lose as much as half of their body weight during hibernation. The torpor state also allows them to adapt to surrounding temperatures. Bats can lower their body temperature from around 100 degrees to 40 degrees or less as needed to preserve energy.

Prevention – Our Preferred Approach

Our preferred approach is prevention—keeping bats out before they move in.

Bats can enter your home through an opening as small as a quarter of an inch. Keeping them out requires careful inspection and attention to detail.

We recommend the following steps to help ensure that mother bats and their young resist roosting in your attic this year:

• Identify and seal all cracks in the home’s exterior using caulk, weather stripping, or wire screening as needed, including around windows.
• Hire a professional to cap all chimneys and air vents in and around the home and garage.

If you suspect a bat colony in your attic, contact us for a professional inspection. Our bat removal experts know how to properly manage exclusion.

Important: Do NOT seal holes until all bats have been properly removed. You must ensure that every entry point is addressed. These animals are used to being there—it’s their home now. If you miss even one spot, they will find it, and you may not realize they’ve returned until it’s too late.

Just like you typically enter your home the same way each time, so do they. But just like you, they have alternative entry points—and so do they!