The bats found here are Mexican Freetail Bats. These winged crusaders are insect eaters that clear the night of pesky bugs. They actually live here only during the Summer months, and they come here to give birth and raise their young in the caverns.

Bats use echo location to find their way in the dark, and each one uses it's own unique frequency. Similar to how we humans have different voices.

The bat populations have been in decline here for sometime, and no one knows exactly why. Today the bats number around 300,000, while it is thought that there were over one million bats here when James White entered the cavern in 1898.

The Mexican Free-tail bat weighs only half an ounce, but has an 11 inch wing span. Bats reside about 1/2 mile inside the cave hanging in close groups 30-80 feet above the cave floor, but they are not near the tour route .

Although the bats usually leave starting somewhere between 7:30 and 8:30pm, this is not always the case. Sometimes they don't leave until as late as midnight and sometimes not at all.

In Winter it's not known exactly where the bats go, but it is believed to be Northern Mexico.