by Harry Noyes, Bexar Audubon
Society
From the October/November 2000 Issue
of "Bexar Tracks," the BAS
Newsletter
The visual spectacle was all it was
billed to be, but it was the sensations no one had mentioned that struck me
most.
The pungent smell of guano, of
course, but more surprisingly the quiet, insistent humming and soft downward
breeze off thousands of rapidly beating leathern wings.
A narrow, twisting river of bats
writhed just above the low trees above our heads, not more than 15 or 20 feet
off the ground – close enough to see the tiny heads projecting in front of the
pulsing wings.
Soon those tiny heads would be
chomping down on myriads of moths with the gusto of velociraptors.
Some 200 tons of insects die in those sonar-guided jaws nightly.
So massive are the fleets involved
in this nightly air battle that human radar can pick up the scene as the stream
of bats closes with the stream of bugs 5,000 feet or more up in the Texas sky.
No one really knows how much money the bats save
That night more than 30 million bats
would boil out of
By this late August evening, the
maximum summer load had already been trimmed as some of the bats had dispersed
from the jam-packed cave to other roosts. Others had succumbed to nature's
rigorous winnowing.
A hawk swooped through the
chiropteran flow this dusk and returned to a nearby tree, presumably with a
small wingy corpse to shred and swallow. One observer
saw the snake that hangs around the mouth of the cave grabbing bats that fly
too low.
But the huge population of bats –
believed to be the greatest single concentration of mammals of any kind at any
place upon the Earth -- hardly notices such losses.
Unfortunately, other bats in other
places suffer unnatural losses whose impact cannot be ignored. Many species of
bats around the world are endangered by human ignorance and greed – through
habitat loss, persecution and even hunting for food.
Americans may not eat bats, but many
of us are no less superstitious about them than the peoples
of developing lands. Just recently, many local people were thrown into near
panic by inaccurate TV reports suggesting that rabid bats were fluttering
everywhere.
The truth is, that while bats can
get rabies, only a tiny percentage do and rabid bats
typically avoid human contact. Virtually the only humans who ever get rabies
from bats are people who foolishly handle bats they find lying on the ground.
There are many reasons besides rabies
for bats to fly around in daytime, especially in the late summer when many
young ones are just learning to fly and hunt and may get lost trying to return
home at dawn.
Certainly the tiny risk of rabies
from bats is far outweighed by the human lives they save, through consumption
of disease-bearing insects, through crop-protection that reduces pesticide use,
through pollination and seed-dispersal by vegetarian bats that preserve crucial
plant species.
The 65 or so members and guests of Bexar Audubon Society who visited
But ultimately it was the bats
themselves that taught the most important lessons, about the beauty, the
majesty and the sheer incredible vastness of life on Earth. The several dozen
fortunate folks who stared upward at that seemingly endless river of bats,
open-eyed and sometimes open-mouthed with awe (despite warnings that guano has
to start somewhere), left with a clearer appreciation of this wonder of the
biological world and how much we stand to lose if we do not safeguard places
like Bracken Cave and the creatures who reside in them.