Carlsbad bats "free-tail it" back from Mexico
by Rick LoBello
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.
