Wildlife biologist explains bat myths

Myth: They always live in caves

During the warmer months, bats can roost in many areas: tucked into the loose bark of a tree, behind a leaf, hanging from the eaves of a church or curled up in the rafters of an abandoned barn. The 10 species that live in Maryland are tiny, weighing as little as a nickel and as much as a quarter, and are about the size of a hand with their wings extended. During the winter, half these species migrate south, and the others head into caves to hibernate.

"Caves offer a great winter hibernating habitat," said Browne. With constant humidity levels and temperatures a degree or two above freezing, they offer a safe environment where bats can huddle together or on their own, out of the elements and protected from predators.

Myth: They can't see

While bats are famous for using echolocation, they do have some vision. Echolocation requires a lot of energy, so they use it judiciously.

"They're basically screaming at an extremely high frequency," she said. They have to think, "Is it worth my effort, the calories, to explore this thing that may be food, or to decide if this is an obstacle or predator I need to avoid, or a potential mate I should explore?"

They can use their limited vision to supplement echolocation as they travel familiar paths, she said, much like a human can commute home without stopping to carefully read every road sign.

Myth: They're just scary sky rats

Bats get a bad rep for carrying rabies (in fact, less than 1% do), but they play an important role in the ecosystem. In Maryland, they're one of the primary predators of pests like mosquitoes, stink bugs and crop-destroying beetles. Just one little brown bat, a species common in the state, can eat 1,200 insects in an hour. In other parts of the world, they pollinate plants like bees and feed on fruit and disperse seeds like birds to help rejuvenate entire forests.

Bats are under threat themselves, not only from human-induced habitat loss, but from White-nose Syndrome, a fungus that has killed nearly 7 million bats across the country since 2006. Wind turbines also cause mortalities in migrating bats and birds.

"We don't need to fear them. They are not trying to harm us," Browne said. "They're just going about their lives and raising families, just like we are."