Carlsbad bats "free-tail it" back from Mexico

Photo credit: Copyright Gautam Shah

Carlsbad bats "free-tail it" back from Mexico

by Rick LoBello, iloveparks.com

Second only to the marvel of the caverns themselves, Carlsbad Caverns National Park's sunset bat flight ranks as one of the most fascinating wildlife spectacles in North America. Although the bats are miniscule in size compared to larger mammals like Alaska's caribou and the Pacific Coast's humpback whales, few wildlife dramas can compare to Carlsbad's "main event."

Every evening from early May through October, swarms of nearly 800,000 Brazilian free-tailed bats exit the cave's natural entrance to feed on night flying insects like moths and mosquitoes. Park visitors packing the amphitheater are amazed at the sight. This is definitely the place to be on a New Mexico summer night.

In grand fashion the National Park Service seizes nature's exceptional moment as park rangers present bat fight amphitheater programs. Every evening rangers answer dozens of questions while correcting popular myths about bats. For example many people believe that bats are blind. Actually all bats can see, some better than others depending on their feeding habits. A bat hunting on insects at night does not need to see as well as a fruit eating bat in the tropics.

As the audience patiently awaits the rising curtain on the Cavern's big show, vociferous cave swallows fly overhead in search of their last meals for the day. These dive-bombing acrobats must know that soon they will be forced out of the way by an imminent barrage of bats taking over their air space above the entrance to the caverns.

Few people realize that the park's cave swallow colony, about two thousand strong, also has the distinction of being the largest such colony known to the United States. Nesting along the walls of the natural entrance these beautiful birds, more typical of Mexico, are often at first glance mistaken for bats. But in stark contrast to the squeaking sounds of the swallows, the near silent exiting of bats is a completely different picture.

As the flight develops, a large black cloud appears in the summertime sky, the same cloud that first attracted early Carlsbad explorer Jim White to the cave in the early 1900s. Come September Carlsbad's bat colony begins to migrate south to spend the winter months in Mexico. The migration extends into October and sometimes early November as the maternity colony departs the area in smaller groups. Although much is still unknown about their travel route, we do know that the migration extends at least 800 miles. Information on Carlsbad free-tailed bats was first obtained during the 1950s when more than 100,000 bats were tagged with wing bands. Three Carlsbad individuals were eventually recovered. One traveled to Central Mexico covering over 800 miles in 68 days.

Despite extensive studies in search of banded bats, little is known about the break-up of the colony during the winter months. Do some of the larger groups migrating from Carlsbad stay together or do most of them break up into smaller groups or separate as individuals?

Learn more about Carlsbad's bat colony on the Carlsbad Caverns National Park website. You can also support conservation and research on bats by Adopting a Bat from the Carlsbad Caverns Guadalupe Mountains Association.