Bats play an important role in our environment, providing natural insect control and pollinating agricultural crops, among other benefits. But most homeowners consider them undesirable as house guests.
About Bats
The nocturnal habits of bats create a sense of mystery about them, since they’re not readily viewed. As a result, numerous myths have developed around bat behavior, but the truth about bats is just as fascinating as the lore.
These are the only mammals that fly – and they’re fast, clocking speeds up to 60 miles per hour, though five to 10 miles per hour is typical. Bats aren’t blind, but they fly in the dark when there’s less competition for night-flying insects, relying on echo-location to navigate at night and find their prey. When they emit sound waves of high-frequency they receive information on distance, speed, direction, texture and size of an object from the sonar, or reflected sound waves
They also like the cool temperatures of the evening, which moderate the body heat generated during flying.
Annual Cycle
Bats both migrate and hibernate, which may explain why such small creatures live so long — six to seven years on average. They emerge from hibernation in the spring and migrate to summer habitats. Male and female bats roost separately, as they have different temperature requirements. Male bats roost alone or in small groups. Female bats tend to build up in larger numbers – up to several hundred.
Female bats give birth to a single pup in mid-summer. Pups fly at two to three weeks old, becoming self-sufficient within a month after birth. Nursery colonies begin to break up at this point, moving to other feeding sites or beginning their fall migration to hibernating sites. Bats return to the same roosts year after year.
Bats in the House
Rock crevices and tree cavities provide natural roosting sites for bats, but human-made structures also present suitable conditions that tempt them inside. They can enter a house through an opening the size of a quarter, often roosting in attic rafters or behind a wall. As their numbers build up, the sight and smell of bat guano (droppings) may become offensive and clean-up can be a costly undertaking.
Bat Removal
Don’t try to remove bats from your house in mid-summer, when the pups are young and not yet leaving the roost. Trapping bats inside will drive them elsewhere in the house or lead to their death.
If a bat flies into your house, turn off the lights and open doors and windows so they can find their way out. Less than one-half of 1 percent of bats contract rabies but precautions should be taken. Avoid handling bats, but if you must, wear gloves or catch them with a cardboard box or pillowcase to release them outside. Make sure your pets are vaccinated.
The best time to take action to prevent or remove the potential for bats roosting in the house is before they migrate in the spring or after they leave in the fall. All access points should be sealed with screening or polyurethane foam. Installing a sleeve exit over an entry point will allow bats to exit but not get back in. You can also discourage them by interfering with their sonar by hanging Mylar balloons or strips of Mylar aluminum foil.
When the entry points are numerous or bat colonies large, you may need help from a professional to ensure successful bat control in South Florida.