Bracken Cave is the summer home to the largest colony of bats in the world. An estimated 20 million

Mexican free-tailed bat The Mexican free-tailed bat or Brazilian free-tailed bat (''Tadarida brasiliensis'') is a medium-sized bat native to the Americas, so named because its tail can be almost half its total length and is not attached to its uropatagium. It has been ...

s roost in the cave from March to October making it the largest known concentration of mammals. The cave is located in southern

Comal County, Texas Comal County ( ) is a county located on the Edwards Plateau in the U.S. state of Texas. As of the 2020 census, its population was 161,501. Comal County is known for its rich German-Texan and European history. Its county seat is New Braunfels. ...

, outside the city of

San Antonio ("Cradle of Freedom") , image_map = , mapsize = 220px , map_caption = Interactive map of San Antonio , subdivision_type = Country , subdivision_name = United States , subdivision_type1= U.S. state, State , subdivision_name1 = Texas , s ...

. The -wide crescent shaped opening to the cave lies at the bottom of a sinkhole, formed when the roof of the cave collapsed. The cave and undeveloped around it are owned by

Austin, Texas Austin is the capital city of the U.S. state of Texas, as well as the county seat, seat and largest city of Travis County, Texas, Travis County, with portions extending into Hays County, Texas, Hays and Williamson County, Texas, Williamson co ...

-based

Bat Conservation International Bat Conservation International (BCI) is an international nongovernmental organization working to conserve bats and their habitats through conservation, education, and research efforts. BCI was founded in 1982 by bat biologist Merlin Tuttle, who ...

, which restores the land to support native vegetation and an abundant variety of wildlife. Bat Conservation International bought the initial from the Marbach family in 1992, and has been assisted in preservation efforts by

The Nature Conservancy The Nature Conservancy (TNC) is a global environmental organization headquartered in Arlington, Virginia. it works via affiliates or branches in 79 countries and territories, as well as across every state in the US. Founded in 1951, The Natu ...

. Access to the cave is restricted to protect the habitat of the resident bats. Bat Conservation International offers evening guided tours to the cave to watch the bats emerge from the cave.

In media

Bracken Cave has been featured in the media several times since its discovery. The

National Geographic Wild National Geographic Wild (shortened as Nat Geo Wild and abbreviated NGW) is a global pay television network owned by National Geographic Partners, a joint venture between The Walt Disney Company (73%) and the National Geographic Society (27%). T ...

channel included Bracken Cave in the ''World's Weirdest'' series episode "Freaks of the Sky." It was also featured in the first pilot episode of ''

Dirty Jobs ''Dirty Jobs'' is an American television series that originally aired on the Discovery Channel in which host Mike Rowe is shown performing difficult, strange, disgusting, or messy occupational duties alongside the job's current employees. The sh ...

''.

Bat haven

The Bracken Cave is the destination every March or April of over 20,000,000 Mexican free-tailed bats (''Tadarida brasiliensis''). These bats fly as much as from Mexico to this cave. After arriving in the cave, the migrant mothers give birth to pups. An astounding 500 pups have been recorded clinging to of the cave walls—an ingenious way for keeping warm; the temperature is around . The city of San Antonio, a local developer, and conservation groups reached agreement on "a $20 million deal" in 2014, to ensure that human development would not encroach on the bats, and that the sky near their cave would remain dark at night. Tadarida brasiliensis

Farming benefits

From March to October, the bats at Bracken Cave emerge between 6 and 8 p.m. flying southeast on a collision course with bugs such as cotton bollworth moths and army cut-worm moths being pushed away from crops southwest by winds. The bats consume several tons of insects per night, which according to research conducted in 2006, saves cotton farmers in south central Texas about a year.

Unknown bat count

While the Bracken Cave bat roost is often estimated at 20 million, the true number of bats is unknown due to unreliable counting methods. An animal behavior expert named Leonard Ireland, who researched the bats at Bracken Cave in the 1960s and 1970s, once said the clouds of bats emerging from the cave were up to " long and wide."

References

External links