Austin bat-watching scenes

Austin is known for its Mexican free-tailed bats (Tadarida brasiliensis). More than 1 million Mexican free-tailed bats call Austin's Congress Avenue Bridge "home." While in residence each year, these bats provide a valuable service to Central Texas by consuming more than 4 million pounds of insects.

The hotter and dryer the weather is, the hungrier the bats are, and the earlier they must emerge to hunt. During the best flights, up to five columns of emerging bats can be seen for miles as much as 45 minutes before sunset.

Each spring, free-tailed bats migrate from central Mexico to roosting sites throughout the southwestern United States. By mid-March, hundreds of thousands of mother bats arrive in Austin.

In early June, each one gives birth to a single baby, called a pup.