Carlsbad Caverns National Park is home to a diverse array of wildlife, most notably its famous colony of Brazilian free-tailed bats (also called Mexican free-tailed bats). During the warmer months, hundreds of thousands of these bats emerge from the cave at sunset in a spectacular "flight program." Beyond the bats, the park hosts 17 other bat species and several specialized "cave dwellers" like the Cave Swallow. On the desert surface, you can spot mammals such as mule deer, mountain lions (cougars), javelinas, and the ringtail (a member of the raccoon family). The park is also home to desert-hardy reptiles like the mottled rock rattlesnake and various lizards. In the Chihuahuan Desert surroundings, you might encounter desert cottontails and black-tailed jackrabbits. Birdwatchers can see roadrunners and golden eagles. The park maintains a delicate balance, where the nutrient-rich "guano" (bat droppings) inside the caverns supports a unique ecosystem of tiny cave-dwelling insects and microorganisms that never see the light of day.