Put a Bat In Your Belfry

By Bill and Gail Herald

What's that? You don’t have a belfry? Don’t even know what a “belfry” is? (insert definition here). Not to worry. You don’t need a belfry, but you do need bats!

When our summer weather starts to feel more like the Amazon Jungle, the term “bug days of summer” starts to have more relevance than the familiar “dog days of summer.” Every year, people start to ask about ways to lower their neighborhood “bug index.” With the health of our Chesapeake Bay now in more peril than ever, people are interested in environmentally-conscious ways to reduce the bugs without using chemical sprays and other poisons that eventually leach into the Bay.

So, don’t spray poisons; put up a birdhouse instead. Birds are major bug fighters. As an added bonus, some of the best insect-eating birds are the most beautiful and fun to watch, such as Carolina Wrens, Eastern Bluebirds, Ruby Throated Hummingbirds and Purple Martins. These avian “All-Stars” are among the most popular and desirable birds in our area. Although each bird and species has a different appetite, they can consume up to 2,000 insects each day per bird.

That’s impressive! But this record of avian appetites is completely eclipsed by another airborne acrobat: the bat! Studies show that a healthy bat can consume in a single hour what a bird eats in an entire day! It is possible for a bat to literally eat its own weight in insects in a day! Try that the next time you order pizza!

Bats are the champion insect eaters of our area, yet many people know little or nothing about bats. Worse yet, many people are afraid of bats, still believing old tales and superstitions that have no basis in fact. Compounding this ignorance and prejudice against our fellow-mammals is a lack of awareness. Many people do not know that bats are here and all around us on a daily basis. They just don’t know about bats, how they live and how they can go to work eating insects in their neighborhood. With a little knowledge, effort and persistence, you can diversify the ecology of your backyard and enjoy fewer pesky insects at the same time.

Fear is the first obstacle for many people. They recall old movies about hordes of blood-sucking vampires flying into bedrooms through open windows. Who wants to become a close friend of Count Dracula? The truth is very different. There are no vampire bats in North America. Although there is such a creature in South America, they are a relatively uncommon pest of cattle and other livestock on large ranches. They don’t like people.

A second fear is based upon a complete misunderstanding. Some people are afraid that a bat will fly into their hair and get tangled up and caught. This fear seems to stem from the belief that bats are blind and are thus apt to bump into things like bee-hive hairdos. In truth, bats see quite well. What is truly exceptional, however, is their hearing. Because most of us navigate by sight, it is hard for us to understand that bats see well but actually navigate with exceptional precision using sonar. Using sound, they hunt by a technique known as echolocation. They are constantly emitting noises and forming a mental image of their prey by the sound waves that bounce back from the flying insect. Thus, bats know exactly where you are and are not going to get tangled by accident in your hair.

And no, there is little fear of rabies from bats. Studies show that they are less-likely to be rabid than dogs and cats.

Quite understandably, bats are exceptional flyers. Because they feed on tiny insects that flit through the air, bats are known for their acrobatic flight that swoops and turns in ways that are very different from a bird. Bats often make “Figure 8” patterns in the air as they cruise a likely spot for a tasty bite to eat.

In our area, bats are most often seen at dusk as they swoop and dive feeding on insects. Our most common bats are the Big Brown Bat and the Little Brown Bat. Both are actually quite small. The ferocious sounding Big Brown Bat is about the size of your index finger and weighs less than one ounce. The Little Brown Bat is more like your pinky finger and weighs in a less than one-half ounce. Both are upstanding citizens in our ecosystem, doing lots of good deeds and getting little recognition for their hard work.

Bat experts now identify at least two types of bat houses, each appropriate for a different life-stage. The most common is the bat version of the bachelor pad. This type of house seems to attract young male bats who seem most interested in “hanging out.” These bat boxes are relatively thin-profile rectangles, designed for housing up to 30 bats in a shape that is somewhat reminiscent of an old fashioned washboard. The second type of bat box is designed for duty as a maternity ward. In these larger boxes, up to 50 mothers and children huddle together in a sort of communal nursery.

Recent studies show that position and number of bat houses have an influence on occupancy. The best location for a bat box is on a pole or the side of a building, at least 10-12 feet off the ground, where it will receive at least six hours of direct sunlight every day. A clear area of 15-20 feet in front of the box is needed for take-offs and landings. A location within a quarter mile of a lake, river or stream is preferred. Multiple houses in the same area increase the likelihood that the houses will be occupied.

Attracting bats to a house is not a certainty, but a well-located house will have the best chance for success. Although bats roost in the springtime, it can take a year or more for a box to be occupied. A good strategy can be to put out a bat box in the summer or fall in order for the box to be noticed and ready for occupancy when the bats are ready to roost.

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