Deep in the heart of Texas, deep inside a cave, millions and millions of Mexican free-tailed bats roost together. One square foot of the cave's ceiling can contain more than 500 of them. When it comes to bat colonies, it turns out everything really IS bigger in Texas.

Bracken Cave Preserve, located just outside San Antonio, is home to the largest colony of bats in the world. "We have somewhere in the neighborhood of 20 million Mexican free-tailed bats," said Fran Hutchins, director of Bat Conservation International.

Bats can be found all throughout the Lone Star State – the ones that roost under the South Congress Bridge in Austin have even become a tourist attraction.

But there's nothing quite like Bracken. When a vortex-full of bats emerges from the cave to feed each evening, the resulting "batnado" is so massive it shows up on doppler radar. They're headed out to surrounding fields to spend the night feasting on insects that feast on crops like corn and cotton. Bats are a natural form of pest control.

"Farmers love bats," said Hutchins.

But the rest of the world doesn't necessarily. "They're not sure about bats," Hutchins suggested. "[For] a lot of people, what they know about bats is whatever horror movie they saw last."

In pop culture, bats are depicted as terrifying bloodsuckers. Even Batman himself is afraid of bats! But one wealthy Texas entrepreneur fell in love with the Bracken bats, inspiring him to pull a Bruce Wayne and build his own bat cave.

David Bamberger co-founded the fast-food chain Church's Texas Chicken. In the late 1990s, concerned about threats to the bats' natural habitat elsewhere in Texas, Bamberger built a giant cave on his sprawling ranch Selah, near Johnson City.

For a long time, no bats showed up.

The millionaire who'd gone batty was big news at the time. CBS News' Jim Axelrod interviewed him in 1999, after Bamberger had sunk $175,000 into his empty bat cave.

The cave was a colossal flop – until one night, when Bamberger heard the flapping of thousands of tiny wings: "Bats were pouring out of there by the thousands," he said. "Tears were running down my face. Oh, I'm so happy!"

Today, Bamberger's cave, which he's dubbed the "chiroptorium" (bats are members of the order chiroptera, meaning "hand wing"), is home to a couple hundred thousand bats, part of his larger conservation-focused preserve. It's impressive … romantic, even.

Joanna Bamberger recalled her first date when she was asked, "Would you care to come and see my bat cave?"

What's a gal say to that? "At my age, I've had every come-on in my life, but I've never been asked to see a bat cave before," she laughed.

David Bamberger is a 95-year-old newlywed; he married Joanna Rees Bamberger earlier this year. The two still come out to see the bats most evenings. "You sit there absolutely agog, because it's just wonderful to look at," she said.

Looking at the faces of high schoolers on a field trip to Bracken Cave, you don't see fear; you see awe.

Hutchins said, "The fun part is watching people that have never seen a bat fly or a bat this close. It can be very emotional for some people."

The majority of these Mexican free-tailed bats will be back in Mexico soon to spend the winter. They won't return to Texas to have their babies until sometime next spring, when they will continue to delight instead of fright. 

     
For more info:

• Bracken Cave Preserve, San Antonio (Bat Conservation International)
• Selah: Bamberger Ranch Preserve, Johnson City, Texas

     
Story produced by Dustin Stephens. Editor: Lauren Barnello. 

     
See also: 

• Nature up close: The largest bat colony in the world ("Sunday Morning") 
• Behind the scenes: Filming bats ("Sunday Morning")
• U.S. bat species devastated by fungus now listed as endangered
• The facts you didn't know about BATS! ("Sunday Morning")