Female Mexican free-tails started roosting in the cave shortly after it was completed, said Lisa Blyler, public information manager for the Flood Control District. They’ve been there every ...

An Arcadia flood control tunnel is home to a colony of 10,000 Mexican free-tailed bats. Here's how to visit them.

During the summer months, a tornado of roughly 20 million Mexican free-tailed bats emerges from Bracken Bat Cave. The population swells around June after female bats give birth to a single pup.

Since the Bracken Cave is the largest known bat maternity colony in the world, the female bats produce millions of young bats each year. By the end of July, they're ready to test their flying ...