Drove to New Mexico on Monday. Stopped at Carlsbad Caverns for the night.
We're through birding for a while, so we didn't stop for birds. We didn't
stop to descend into the caverns either. We stopped so we could catch the
flight of the bats. It is quite a spectacle this flight of the bats. The
natural entrance to the caverns is an open pit, with a bat observation
amphitheater built into the hill on one side. In the afternoon, this open
pit is filled with cave swallows darting in and out, chirping and swirling
the last of their bug eating business of the day, before they settle down
for the night. The cave swallows are the warm-up act. Just before dark,
the main event begins. Not a single bat. Nothing. Then, suddenly, four
hundred thousand famished insect eating machines. They can't come out all
at once. They flow. The flowing swirling mass makes it's way to the sky.
Out of the pit in a counterclockwise swirl, three rotations, forming a
single undulating stream off into the night sky. The stream follows a fluid
path, not like a stream of water, but more like a wandering wisp of smoke,
flowing away, then coming back. When it wanders directly overhead, we're
bathed in the fluttering of thousands of tiny bat wings.
Each bat weighs half an ounce. All these bats together will consume three
tons, the equivalent of three Volkswagen beetles in weight, of insects
tonight. It takes thirty minutes for four hundred thousand bats to blow out
of the cave. They will feed all night, up to forty miles away, and return
by four am.
On the way to the bat program, a scott's oriole flew across the road in
front of us.
