Carlsbad Caverns National Park
Hundreds of thousands of Mexican free-tailed bats, whirling counterclockwise, spill forth from a gigantic hole in the earth and are silhouetted against a colorful desert sky... this is the bat flight experience at Carlsbad Caverns National Park.
Prior to the evening flight of the bats, a talk is given at the cavern entrance by a park ranger. The starting time of the talk varies with sunset, it is best to call the park at 505-785-2232 or check at the visitor center for the exact time. Programs may be canceled in the event of inclement weather. The bat flight talks are scheduled from Memorial Day weekend through the end of September. There is no charge for the bat flight program. In late October or early November the bats migrate to Mexico for the winter, they return in April or May depending on the weather.
The best bat flights normally occur in August and September. At this time baby bats, born in the early summer, join the flight along with migrating bats from colonies further north.
The daily pre-dawn return of the bats is different from the evening exit flights but are just as impressive. Early risers can see the bats as they re-enter Carlsbad Cavern with spectacular dives from heights of hundreds of feet. Individual bats diving in from every direction may reach speeds of 40 km/h (25 mph) or more.
Bat Flight Breakfast
A bat flight breakfast is held annually, usually on the second Thursday in August, from 5 a.m. to 7 a.m. Park employees sponsor this breakfast once each year. A special program is given and other activities may be scheduled as staffing permits. A reasonable charge is made for the breakfast. Regular cavern fees apply for entry into the cave following the breakfast.
For Your Comfort and Safety
Flash photography is not permitted at the program, nor are flash cameras. The flash disturbs the bats exiting and re-entering an important maternity roost. Spaces to accommodate people using wheelchairs are located at the entrance to the amphitheater. Restrooms are available and fully accessible. Pets are not allowed in the amphitheater area.
Nearly 1,000 feet below the surface, and over a mile from any known opening, lives a colony of about 100 Fringed myotis bats. This maternity colony roosts just above Lake of the Clouds, the lowest and warmest point in Carlsbad Cavern.
Researchers found that most Fringed myotis bats exit the main cave entrance with the Mexican free-tailed bats; a few depart through the smaller second natural entrance. This opening, located 200 yards east of the main cave entrance, is surrounded by a fence. It was also found that lights left on in the cave delayed the emergence of the Fringed myotis bats. Rangers now turn out all lights in the cave at the end of each day.
This research was funded with a grant from the Adopt-A-Bat program, a nonprofit fund that supports bat conservation, education, and research.
Counting the Bats
The colony of Mexican free-tailed bats at Carlsbad Cavern declined from an estimated 8.7 million in 1936 to approximately 200,000 in 1973. Similar declines have been noted throughout the southwestern United States and Mexico. The pesticide DDT is thought to be the primary cause.
In 1996 infrared photographs were taken of the ceiling in the Bat Cave of Carlsbad Caverns. The spring pre-birth population of Mexican free-tails was estimated to be about 193,000 bats. The population nearly doubled to an estimated 352,000 bats by fall when the young were flying. The population of the bat colony fluctuates greatly from season to season. It also changes daily, perhaps in response to conditions of drought or rain, food availability, or the life cycle of the bats. Research on the diet and activity level of the bats will help biologists to understand the causes of population change.
Experiments with recording the sounds made by bats are ongoing. Eventually we hope to correlate this sound "signature" with the population estimate from the photo-monitoring method. Sound recordings taken throughout the night have the additional benefit of helping us to understand bat behavior during various seasons, weather patterns, or disturbances.
Details mentioned in this article were accurate at the time of publication