Bracken Cave: See the Most Bats in the World!
Bracken Cave

Here we are outside Bracken Cave near San Antonio where 15 million bats live in the summer. Photo: Teresa Nichta

Where can you find the most mammals in any single location on the planet? The answer is…in Bracken Cave. And just where is Bracken Cave? If you drive about halfway between Austin & San Antonio Texas, and you have a reservation, you will find the giant mouth of a cave.

And, if you are looking for the highest concentration of mammals in the world, look no further. Seriously? We imagine the most mammals in the world would be in Africa on the Serengeti during the Great Migration. All those wildebeests, zebras, and gazelles coming together, but we are wrong.


How Many Bats Are at Bracken Cave?

bat facts

Over 15 million Mexican free tailed bats spend their summer at Bracken Cave. Photo: Merlin Tuttle

Every spring, fifteen to twenty million female Mexican (also called Brazilian) free-tailed bats descend on Bracken Cave near San Antonio, Texas.  They all come from Mexico with one purpose. To give birth to a single pup (baby bat), raise their baby and then go back to Mexico. So it is not only the largest group of mammals in one location, it is also the largest maternity ward. Very cool.

Bats are Great Mothers

bracken cave

The mouth of Bracken Cave where the bats are starting to emerge. Photo: Teresa Nichta

But back to Bracken Cave. Inside the cave, the babies are packed onto the cave walls to the tune of 500 per square foot. That is a lot of baby bats.

So how does the momma bat find her pup when she gets back to the bat cave? It is believed by her sense of smell which is an incredible feat with all those babies. 

Luckily, bats are some of the best mothers of all. They groom, nurse, and teach their youngsters to fly. The babies nurse for 4-5 weeks and then start venturing out with their moms.

Unfortunately, only about 50% of the babies survive. Flying collisions and predators all take a toll on the little pups. It is fascinating to watch the hawks circling overhead, hoping to pick off a mother bat. While on the ground, the raccoons and snakes wait by the cave mouth for a baby bat to attempt to fly and fall.


And How Many Insects Does a Bat Eat? 

bracken cave

Standing in awe of the millions of bats circling

All the while, they are eating literally tons of insects every night, helping keep mosquito and other pesky insect populations at bay. In a single night, the bats from Bracken Cave can eat 140 tons of insects, saving farmers thousands of dollars in unneeded pesticides for their crops.  Now that is impressive!

To learn more about this amazing animal, read our “Bats” blog. You might be surprised to discover bats rarely carry rabies and they will never fly into your hair!

Who Owns Bracken Cave?

bat cave

The bat cave is located between Austin & San Antonio, TX

So who owns this magnificent bat cave? The cave is owned by Bat Conservation International (BCI) who limits access to the cave. Reservations are required in order to minimize disruption to the bat colony. The property surrounding the cave was saved from development through a joint effort by BCI, The Nature Conservancy,  and the City of San Antonio. Talk about a conservation success story.

The Great Merlin Tuttle

Merlin Tuttle

Merlin & Dale are checking out the bats

We visited the bat cave as a guest of the world-renowned bat expert, Merlin Tuttle and his wife, Paula. Merlin is the founder of Merlin Tuttle’s Bat Conservation and has done more to save bats worldwide from wrongful persecution and harm than any other human.

He was also a driving force in saving the bats that live in Austin. So it is quite an amazing experience to be visiting the caves with Merlin and some of his team. And it doesn’t hurt that Paula is a native plant expert. We learn so much as she points out all the cool native plants around Bracken Cave. A double win for us!

For us, it was one of the most moving, mind-blowing experiences either of us have ever had. Ever! Who knew 20 million (give or take a few million) bats live in a cave and come roaring out every night in search of insects. And each one of those bats is caring for a pup inside the cave when they return at dawn.

We also learned more about Merlin’s continued conservation initiatives through his website (where you can see some additional amazing photos) and his inspiring, informative book, “The Secret Lives of Bats”.

Bat Art for Conservation

Dale also got a number of ideas for bat sculptures from our visit to Bracken Cave. All the money raised from future bat sculptures will be used for bat conservation.

“Cliff Hanger” is one of his earlier sculptures which you can check out in our Art for Wildlife section.  

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Cliff Hanger by Dale Weiler was sold to help bat conservation

Bats Are One of the Most Important Mammals on the Planet

Bracken Cave

We think bats are one of the most important mammal on the planet.Photo: Merlin Tuttle

We believe bats are one of, if not the most important, mammal on the planet!  Help us debunk the myths, provide habitat and spread the word about these incredibly beneficial creatures. Become a bat advocate and make a difference in wildlife conservation.