Vital to Ecosystem : Many Still in the Dark About Bats
As dusk settled, the first of the bats made their move.
They darted at the entrance of the darkened cave, whipping back and forth, translucent membrane wings flapping furiously in the stiffening Texas breeze.
Then, as if answering a signal, an ocean of bats, millions of bats, the biggest single bat colony in the world, began to burst through the yawning crack in the earth. They swirled in the natural bowl at the entrance of the cave, gathering themselves into tight groups before moving off for their night’s work--the gobbling up of 250,000 pounds of insects.
As they swept away, others replaced them, repeating the ritual. It would take hours for the bats--about 20 million of them--to leave their roost and dart off into the night.
So what did Merlin Tuttle do, when faced with this bat swarm? He walked right in among them, into the bowl of bats. He flailed his arms around and snagged himself a bat with a one-handed catch.
And what did Paul Vordenbaum do? He pulled out a hip flask and poured himself a nip of bourbon.
“Watch out for snakes,” he warned Tuttle.
Perhaps this scene calls for an explanation. Tuttle is the ultimate batman, the leading defender of the bat cause, a scientist who has spent 25 years studying bats throughout the world. He even has two pet bats, Zuri and Rafiki (Swahili for “beautiful” and “friend”).
Vordenbaum, who watches over the bat cave owned by his cousin, Elgin Marbach, has spent enough time around the nocturnal creatures to realize that a rattlesnake is more menacing. The bats are also a source of income, for Vordenbaum and the Marbachs mine the bat guano in the winter, when their cave dwellers have moved south, and they sell it as fertilizer. Much to Vordenbaum’s chagrin, a good portion of the guano finds its way to Northern California, where it is the fertilizer of choice for marijuana growers.
Darkness was almost complete when Tuttle climbed up the side of the bowl and emerged from the bat swirl holding his catch. By the beam of a flashlight, he put his finger to the bat’s mouth to show that it is not aggressive by nature. Then he talked about how bats are much maligned, mostly because they can transmit rabies. But, he said in their defense, only 10 people have contracted rabies from bat bites in the last 40 years; lawn mower accidents kill more people than that each year.
“They really are one of the gentlest animals around,” said Tuttle, without batting an eye.
Vordenbaum agreed, saying that none of the men who work for him had ever been hurt in the decades of mining guano in the cave, in rocky cattle country just outside San Antonio.
That, however, is not the common image of bats, which make up about a quarter of the world’s mammal species.
They are seen as vile, ugly, rabid and downright scary. They are associated with Dracula, Halloween, moonless nights, haunted houses and evil in general, and they have been for a long time. Consider the ingredients in the brew concocted by the witches in Shakespeare’s “Macbeth”: “Eye of newt and toe of frog, wool of bat and tongue of dog.”
One of the few places in the world where bats are held in high esteem is China, where they are considered a good luck charm. The Chinese word for bat is fu , which also means happiness.
“Bats do need better press,” said Gary McCracken, a University of Tennessee bat expert, one of the few in the United States. McCracken estimates that if the nation’s bat experts all came together for a meeting, it would amount to a good-sized cocktail party.
The point man for educating the public about bats is Tuttle, the founder and president of a group known as Bat Conservation International. A friendly, studious-looking man, Tuttle, 44, founded his organization because the bat population of the world is rapidly being destroyed. And that, he said, would be catastrophic to the earth’s ecosystem, which depends on bats for everything from reforestation to insect control.
In this part of the world, they are being dynamited and their caves are being sealed up. They are being poisoned by fruit farmers and by people who simply do not want them in their attics. In Southeast Asia, the bats are endangered for another reason--they are a gourmet delicacy.
In one case, an Arizona cave housed 30 million bats in the 1960s. Now, there are only 30,000. Such numbers alarm Tuttle, who began his conservation group in Wisconsin, but moved to Texas this year because it is a better place to study bats--"bat nirvana,” he calls it. He has walked through cobra-infested jungles of Thailand at night to bat-watch, had his camp strafed by Peruvians who thought his night activity was larcenous rather than scientific, and has been stalked by curious jaguars and tigers.
“The biggest risk of studying bats is not the bats, but being out at night,” he said.
Tuttle thinks bats are beautiful. He also thinks that people fear bats because they don’t know anything about them.
Bat fear, he believes, can be overcome with bat facts, and these are a few of his offerings:
--The bats from the cave in Bracken alone eat a quarter of a million pounds of insects each night, most of them mosquitoes. “The bats will leave you alone; the mosquitoes won’t,” he says.
--There are almost 1,000 varieties of bats and they live in every part of the world except uninhabitable deserts and the polar regions. In the tropical areas of the world, they are needed for seeding and pollinating rain forests. They also pollinate and disperse seeds in the wild for bananas, plantains, avocados, mangoes, dates, figs, cashews and the agave plant, from which tequila is made.
--As for the bat guano, it is used for other things besides growing marijuana. In the Malaysian state of Sarawak, for example, it is used to fertilize crops that produce almost a third of the world’s supply of black and white pepper.
All this, Tuttle says, and bats still get a bad rap.
“It’s only natural that people fear most what they understand least,” Tuttle said. “Bats have the misfortune of being shy and only active at night, so people come to fear them.”
Tuttle said he tried for years to enlist the aid of major conservation groups to help protect bats, but never received any help. So he founded Bat Conservation International, which now has an unimposing 900 members in 25 countries. One of the organization’s biggest supporters is Bacardi rum, which has a bat as a trademark, a throwback to the days when the company wanted a distinctive symbol that illiterate imbibers would recognize even if they could not read the label.
The president of Bacardi, Bill Walker, said he read a newspaper article two years ago about Tuttle’s group during a time when he was searching for a meaningful conservation effort. Bats were a natural because of the Bacardi trademark.
“It suddenly clicked,” he said. “The interest in conservation became more specific.”
Since then, Bacardi has printed 1 million pro-bat brochures, which the company gives away.
“We get a surprising amount of mail,” Walker said. “I didn’t realize so many people were interested in bats.”
Madison Avenue, though, would have trouble selling bats. They do, after all, carry rabies. And certain species of bats are vampires that live by extracting blood from animals and humans.
Tuttle takes on the first problem by explaining that only sick bats, incapacitated by their own disease, are the ones who bite when they come into direct contact with pets or people. Healthy bats, he said, have about as much interest in being around people as people do about being around bats. So if you do not touch them, and pets are vaccinated, the chance of contracting rabies is almost nonexistent.
“If you want to find a rabid bat, you can find one almost any day of the summer,” Tuttle said. But if you leave them alone, “the odds of being harmed are about the same as being run over by a Mack truck carrying a load of cement while you are at home sleeping at 3 in the morning.”
Others More Dangerous
Dr. Denny Constantine, a California public health veterinarian and one of the world’s leading experts on rabies, said there was more danger of the disease from other animals.
“In surveys, we’ve found that one out of 200 bats was incubating rabies,” he said. “If you go out and collect skunks and foxes, you may find a much higher proportion.”
And, “if you have a colony of bats in your house and one bat has rabies, it’s not likely the other ones are going to get it.”
As for the question of vampire bats, Tuttle dismisses that by saying that there are only three known species and they all live in Central and South America. But human fear of them has decimated the bat population in Mexico.
McCracken, the University of Tennessee expert, said he traveled to Mexico early this year to study the wintering habits of the Mexican free-tail bat, the same species that inhabits the Bracken cave in the warmer months. He had with him a long list of roosting sites, but almost half the caves had been dynamited or burned out by people who feared they might be inhabited by vampire bats. And, Tuttle said, more than 8,000 caves had been destroyed in Brazil for the same reason, further endangering a number of other species.
“The people who don’t know that much about bats think they’re all vampires,” Tuttle said. “I can show you bats that are more distantly related than a sea otter is to a tiger.”
Despite such bad news on the bat front, Tuttle also points to successes since his organization was founded in 1982. He said six of the largest bat populations in North America are now protected by federal agencies and conservation groups because of his efforts, and that governments in other parts of the world are now examining bats in a more favorable light. Tuttle said, however, that the bat cause is still in its infancy.
“The bats have just been neglected, unless they have caused a problem,” he said.
Tuttle thinks, by the way, that every backyard should have a bat house, and will even send out plans on how to make one. What’s good enough for birds, he believes, ought to be good enough for bats.