Eventually the sea evaporated, and the reef was buried under deposits of salts and gypsum. Then, a few million years ago, uplift and erosion of the area began to uncover the buried rock reef.
During the uplift that would become the Guadalupe Mountains, rainwater seeped downward through cracks and faults in the limestone. At the same time, hydrogen sulfide-rich water migrated upward from vast oil and gas fields to the south and east.
These two waters mixed, forming sulfuric acid, which dissolved the limestone and opened up the fractures and faults into the large chambers we see today. As the mountains were pushed up, the level where the rooms and passages in the cave were being formed moved lower into the ancient reef rock. This process created nearly horizontal levels connected by steep passages.
In Carlsbad Cavern, the older Bat Cave level and the younger Big Room level are connected by the steeply descending trail from the natural entrance.
The decoration of Carlsbad Cavern with stalactites, stalagmites, and an incredible variety of other formations began over , years ago after much of the cavern had been carved out. Creation of each formation depended on water that dripped or seeped down into the limestone bedrock and into the cave. As a raindrop fell to the ground and percolated downward, it absorbed carbon dioxide gas from the air and soil, and a weak acid was formed. Once the drop finally emerged in the cave, the carbon dioxide escaped into the cave air.
No longer able to hold the dissolved calcite, the drop deposited its tiny mineral load as a crystal of calcite.
Billions and billions of drops later, thousands of cave formations had taken shape. Oh, the shapes they took! Where water dripped slowly from the ceiling, soda straws and larger stalactites appeared. Water falling onto the floor created stalagmites. Sometimes a stalactite and stalagmite met and merged into a column. Draperies were hung where water ran down a slanted ceiling.
Flowstone was created by water flowing over the surface of a wall or floor while depositing layers of calcite. Cave pearls, lily pads, and rimstone dams appeared where pools of water occurred in the cave. Like pearls from oysters, cave pearls developed as layer upon layer of calcite built up around a grain of sand or other tiny object.
Lily pads formed on the surface of pools, while dams formed where water flowed slowly on the floor. Another type of cave formation that decorated cave walls and even other formations was popcorn, which formed when water evaporated and left behind aragonite.
Aragonite is a mineral chemically identical to calcite but with a different crystal structure. These crystals tend to be small, delicate, and shaped like needles. Some of the more unusual formations that occur in Carlsbad Cavern are helictites.
They grow seemingly without regard to gravity, their twisting shapes governed by crystal shapes, impurities, and the force of water under pressure. Carlsbad Cavern is a sanctuary for hundreds of thousands of Mexican free-tailed bats also.
During the day they crowd together on the ceiling of Bat Cave; a passageway near the natural entrance of Carlsbad Cavern. In this darkened home they are seen only by scientific researchers. At nightfall the bats leave the cave in gigantic swarms. Silhouetted against the night sky like a dark, swift-moving could, the bats make their most dramatic display. Like most species of bats, Mexican free-tailed bats navigate and locate their prey by emitting ultra-high frequency sounds.
Known as echolocation, this natural sonar system is similar to that used by dolphins and whales. When a bat's signals strike an object, they are reflected back and heard by the bat. The bat then takes whatever action is appropriate, whether it be zeroing in on a moth and other flying insects or swerving to avoid a tree limb.
As many as seven types of bats may roost in Carlsbad Cavern, but none is as prevalent as the Mexican free-tailed.
This dark brown to gray bat is distinguished by its long, narrow wings and a free-dangling, skinny tail. Only a part-time resident of Carlsbad Cavern this migratory bat stays here and in other Southwest caves from early spring through October. It flies to tropical Mexico and further south for the winter. Bat Cave serves as a summer home, a daytime refuge, and, perhaps most importantly, as a maternity roost for Mexican free-tailed bats.
The bats, which are mammals, migrate from Mexico to Carlsbad Cavern each year to give birth and raise their young. Young are born in June, under the cover of darkness and away from predators or disturbances. A female usually has just one offspring. Each birth occurs on the ceiling as the mother hangs by her toes and thumbs. The baby called a pup clings to its mother or to the ceiling. For the next four to five weeks, the youngster stays on the ceiling.
During the day, mothers and pups hang in clusters on the ceiling, resting and nursing. As many as bats may crowd into one square foot. At night the young are left in the cave while the adults leave to feed. How does a mother ever find her own baby in the teeming mass of pups? She remembers her pup's location, its scent, and the sound of its cry. In July or August each young bat takes its first flight, joining the adults on nightly forays.
In Bat Cave, bats share their quarters with only a few insects and spiders. The spectacular flight of the Mexican free-tailed bat begins with a few bats fluttering out of the natural entrance of Carlsbad Cavern. Then in a matter of minutes a thick bat whirlwind spirals out of the cave up into the darkening night sky.
Once out of the cave the mass of thousands of bats undulates, serpentine fashion, toward the southeast to feed in the Pecos and Black river valleys. Once there, they gorge on moths and other night-flying insects. Using echolocation, its sonar system, each bat may catch and eat more than half their body weight in insects in a single night. With the coming of dawn, the bats begin flying back to the cave individually or in small groups.
They reenter the cave in a fashion almost as remarkable as their departure. Each bat positions itself high above the cave entrance. It then folds its wings close to its body and plummets like a hailstone into the blackness of Carlsbad Cavern, making strange buzzing sounds as it does.
One by one, the bats return to the safety of Bat Cave, where they sleep until dusk the next evening. Over 1, years ago American Indians ventured into the entrance of Carlsbad Cavern. They left no record of entering the dark zone of the cave, but they did leave mysterious drawings on cave walls near the natural entrance.
In the s settlers discovered the cavern, drawn to it by the spectacle of hundreds of thousands of bats rising up out of the natural entrance in the evening. Some stayed on to mine the huge deposits of bat guano in the cave and sell it as a natural fertilizer. A cowboy named Jim White became fascinated by the cave and spent hours exploring it. White was eager to show the natural wonders of this extraordinary place to others, but few believed his improbable tales of a huge underground wilderness full of unusual formations.
It took photographs to convince skeptics that Carlsbad Cavern was everything it was said to be. In black-and-white pictures taken by Ray V. Davis, who accompanied White on a cave trip, were displayed in the town of Carlsbad, N. They created a sensation. People clamored to see the marvelous cave. White took them on tours that began with a foot descent in a bucket once used to haul bat guano from the cave.
Word of the cave spread, finally reaching Washington, D. Again, there were nonbelievers. In the U. Department of the Interior sent Inspector Robert Holley to see whether Carlsbad Cavern was truly an outstanding natural scenic wonder. Originally a skeptic, Holley wrote in his final report: "I am wholly conscious of the feebleness of my efforts to convey in words the deep conflicting emotions, the feeling of fear and awe, and the desire for an inspired understanding of the Divine Creator's work which presents to the human eye such a complex aggregate of natural wonders.
Later that year Carlsbad Cavern was proclaimed a national monument. White, who continued cave explorations for most of his life, became its first chief ranger. Through illustrated articles in magazines like National Geographic and by word of mouth, Carlsbad Caverns became one of the world's most celebrated cave systems and was designated a World Heritage Site in The park has expanded and now includes 46, acres and over other caves.
For many years cavers felt a strong breeze blowing from the floor of a small cave known as Misery Hole. Despite the rather comical nature of his business, Jim managed to build two houses, both practically on top of the cavern, and provide for his wife and family with the profits he made from fertilizer and tourism. The Monument was introduced at the beginning of his term in office after having taken over from his predecessor, President Warren G. Harding, died of an apparent heart attack in August of the same year.
Sadly, Mr. White died in at the age of 63 of coronary thrombosis and was buried next to his wife, Fannie, in Carlsbad Municipal Cemetery.
While there is no evidence these native peoples explored deep into the cave, they were certainly aware of its existence. Eventually Spanish and European Americans began settling in the area. In their explorations they soon stumbled upon the gaping mouth of what is now known as Carlsbad Cavern. Several of those individuals claim to be the first to have entered the cave, but they have mostly been forgotten by history.
Our first credited cave exploration happened in the cave in Sixteen year-old cowboy, Jim White, was rounding up cattle one evening when he spotted smoke from a wildfire off in the distance. He went into high alert.
Fires could be just as devastating then as they are now. He rode closer to gather information. How big was it? Was it moving quickly? What direction was it burning? These questions and more pushed Jim to ride to the fire so he could report back to camp with the most accurate information possible. As Jim approached the smoke, he noticed something strange: he couldn't smell the smoke, hear the crackling of flames, or feel the heat of fire.
Jim realized he wasn't seeing smoke. He was watching bats. Thousands-upon-thousands of Brazilian free-tailed bats. Jim finally stopped at the mouth of the cave completely mesmerized by the spectacle of flying mammals filling the air above him.
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