Holy Chiroptera, Batman!
Partners of witches? Souls of the dead? Suckers of blood? Knee-deep in guano in a rank Texas cave with the man who knows the shocking truth about bats
Get full access to Outside Learn, our online education hub featuring in-depth fitness, nutrition, and adventure courses and more than 2,000 instructional videos when you sign up for Outside+.
A bat is on my back. Guano covers my boots, and sweat rolls down my face. The bat's tiny claws are working their way toward my neck, scrabbling, I'm sure, for an artery. But I forge on through this fetid Texas cave, shrugging my shoulders, while little Mexican free-tails continue to hurl themselves against me. What did I expect, entering a cave when seven million bats are coming out?
I am not a squeamish person and at times even delight in freakish experiences. But these bats are treading dangerously close to my subliminal fear threshold. They're quick-moving, sharp-toed, and feral. Am I imagining things, or are they a little panicked?
Thankfully, I have the ideal person to cower behind: Merlin Tuttle, de facto PR agent to the bats of the world. Tuttle, 54, founded and is the executive director of Bat Conservation International, based in Austin, Texas, an organization devoted exclusively to promoting and preserving bats. Tuttle has observed more bats in more places than anyone in history, and he is perfectly at ease with bats in his face.
When not among bats, Tuttle likes to talk, to spin yarns about the places he's been, the scrapes he's gotten out of. He'll tell you about the drunken rednecks in Tennessee who threatened to shoot him, the jaguar that leapt into his path in Honduras, and the time he fell 25 feet in an Alabama cave and broke his leg. He has been kidnapped by communist guerrillas in Uruguay and chased by South American Indians wielding curare-tipped arrows. Recovering from a bout of paratyphoid fever–disease is a constant in his line of work–Tuttle says he once hiked 12 miles through the Peruvian jungle, rappelled down a cliff face on vines, and swam across a pond filled with piranhas and electric eels to get to a reputedly excellent bat cave.
Tuttle has brought me here, to Bracken Cave, because it contains as many as 40 million Mexican free-tailed bats–the largest concentration of warm-blooded animals in the world. The cave lies 20 miles north of San Antonio; it is surrounded by private ranch land but is owned by Bat Conservation International. Though the cave is off-limits to the public, the bats emerge each evening from March to mid-November in a magnificent swirling stream that can flow for upward of three hours.
At first, Tuttle had said he was too busy to make this field trip. When I told him I wanted not only to witness the emergence but also to see the bats before they left the cave, he started to ponder. “It's dangerous to go in,” he said. “There's diseases, and there's high ammonia levels from all the guano.” He rubbed his large, squarish chin. He swept back his hair, which is ruler straight, mostly brown but with a surf zone of gray around the lower edges. He narrowed his eyes as his alter egos–creatures as different from each other as day is from night, as bats are from birds–battled: The executive director was a slave to his professional responsibilities; the naturalist was thrilled at the prospect of wallowing in guano. The executive director gave me a long lecture about histoplasmosis, a respiratory disease contracted by inhaling fungal spores found in guano, and airborne rabies, which is extremely rare but a possibility. I nodded to all that, and Tuttle said, “You really are stubborn. You remind me of me.” I knew then that the naturalist had triumphed. Still, Tuttle handed me two pages of liability waivers and allowed himself a split second of doubt: “When it gets out that Tuttle brought this girl to Bracken…” He cocked his head and let out a deep, gnarly laugh. I got out of there as quickly as I could, before he changed his mind.
Back at my hotel, I kept the bat karma on track by steeping myself in BCI propaganda. I read Bats magazine and various bat tracts and fact sheets. Then I watched The Secret World of Bats, an award-winning BCI video. The film contains many dramatic moments: fisherman bats sweeping down in super slow mo to snatch fish from lakes, lesser long-nosed bats pollinating important food crops by shoving their little noses deep into flower pistils, insectivorous leaf-nosed bats using long folds of skin on their faces to fine-tune their echolocation, a vampire bat sucking the lifeblood out of a roosting chicken. Tuttle filmed this bat, the creature for whom most of the world's bat horror is reserved, creeping furtively along the underside of a branch toward a sleeping chicken. Heat sensors located above its nose help it select a spot on the chicken's leg where blood vessels lie close to the surface. The bat licks the leg to soften the skin, punctures it with one swift strike, and begins to slurp blood with its pink, darting tongue. All while the chicken sleeps!
At dusk, I followed a gaggle of white-headed tourists down to Austin's Congress Avenue Bridge to take in America's most popular urban wildlife display: the nightly emergence of about a million and a half Mexican free-tailed bats. The bats roost under the bridge from March till early November. They took up residence here in 1980, after the Department of Transportation retrofitted the bridge and, by happy accident, created long crevices that have just the right humidity and temperature for Mexican free-tails.
Austin did not always love bats. Citizens at first petitioned the city to eradicate the colony. The bats carried disease, people thought. They would spread rabies. Flying rats that mobilized under cover of darkness, they would attack people, fly into their long hair, and drive them insane. Their ideas, in short, were not modern.
Throughout history, bats have figured in folktales, fables, and myths. They have been, variously, male sexual totems, the ghosts of murderers' victims, the souls of the dead, harbingers of rain, partners of witches, deterrents to locusts, and the central ingredient in love potions. In the East, the bat is a good omen, denoting happiness, wealth, peace, virtue, and long life. In the West, the bat is mainly a harbinger of evil, unlucky and unclean. In the Middle Ages, bat blood was believed to prevent the regrowth of plucked hair; the Awakiutl people of Mesoamerica placed bat intestines in cradles to help babies sleep; bat skin is used as a poultice for rheumatism in India. Recently, Merck Pharmaceuticals discovered that the vampire bat's saliva contains an anticlotting compound 25 times more effective than anything on the market today.
“People fear what they don't understand,” Tuttle says. So when Austin geared up to eliminate the bats, he went into educational overdrive, making speeches, going on TV, and producing brochures. Bats, he told anyone who'd listen, are gentle animals. Less than 0.5 percent of the bat population carries rabies, and if a bat does get sick, it lies low. Fewer than 20 people in North America have died of any bat-related disease in the past 45 years.
Tuttle played the ecological-web card: He told Austin that clearings in rainforests would not regenerate if bats weren't around to help disperse the seeds of pioneer plants. He played the utility card: The world would have fewer wild stocks of tropical fruit without bat pollinators, and agave, from which tequila is made, would die. But the most effective ploy in winning the hearts and minds of Austin, not surprisingly, was the personal-comfort card. The Congress Avenue bats, Tuttle said, ate 10,000 to 30,000 pounds of insects a night. A little brown bat, the most common of North America's 44 species, can eat up to 600 mosquitoes in an hour. “I don't want to demonize insects, but I have to say this because that's what people relate to,” Tuttle says. Eventually he prevailed. The petitioners backed down, the city set up special bat-viewing areas, and a tourist attraction was born.
At Congress Avenue, a lady from Lubbock said she's afraid of bats because they carry rabies. I gave her the straight dope. She didn't seem convinced. “I would be afraid if I were isolated with a bat,” her husband said. Why? “Because they're blind.” I told him that bats can see but that because they make their living in the dark, they also navigate with an echolocation system so refined they can detect a human hair in their flight path. “Hmmm,” he said.
By eight, about 50 people were arrayed under and on the bridge, camcorders in hand. They were bored and restless. Finally, at 8:15, the bats began to emerge, spooling out in a ribbon, east over the lake. They swooped and darted, making a beautiful flapping sound, like the pitty-pat of a million people clapping one finger against a palm.
Austin's bats are probably among the best-protected animals in the world. They are the city's totem and its organic pest patrol. Their patron saint lives nearby, and anyone who observes their remarkable exodus becomes complicit in their preservation. But elsewhere in the world, bats are in big trouble. Habitat loss and environmental pollution take the usual toll, but the biggest threat to bats is human ignorance. Entire colonies are lost when people shove burning tires or dynamite into their caves. In Asia, bats are eaten as aphrodisiacs. But surprisingly, it is mine closings, according to Tuttle, that have most devastated bat populations; about a million bats were buried in the last year. “In the last century,” he says, “bats have been chased and harassed out of caves and into mines. They imprint on the mine, and then, when the mine is closed, they die. They have no place else to go.”
Tuttle and I meet the next evening and speak not at all of histoplasmosis. It's 6:30 when we get to Bracken Cave, and immediately we begin to gear up with headlamps, battery packs, and respirators. Years ago, Tuttle inhaled copious amounts of ammonia deep in a nearby bat cave. He walked around for a couple of weeks feeling fluish, became weaker, and then got a friend to drive him to the hospital, where he stayed for ten days. His doctors said his lungs were emphysemic, burned by the gas. They warned him that another exposure could be fatal.
We barely have the headlamps on when I look to the still bluish sky and spot a thin stream of bats. “It's started!” I cry. I had wanted to see the bats asleep, hanging from the cave ceiling. It never occurred to me that we might be entering while the bats were exiting. We hurry up a neatly mowed path to the cave entrance, which sits at the bottom of a crater and rises about ten feet high. The grass around the opening is dead, killed by wafting ammonia fumes. Already there's a warm, pissy smell in the air. “Actually, I've grown to like it,” Tuttle says.
Together we walk down the rocky slope into a vortex of bats. They're coming faster now, in clusters of a hundred or more and then a thin, steady stream. I squat down, about 15 feet from the cave's mouth. Every so often, the wind changes direction and dashes some bats to the ground, victims of wind shear. They quickly recover.
All around us, bats whirl in a counterclockwise pattern, a maelstrom of dark angles. I feel like I've stuck my head in a blender and someone's pushed the puree button. The flapping wings make that beautifully soft sound I heard at Congress Avenue, but multiplied tenfold. Improbably, I'm giggling, overwhelmed by this spectacle, delighted beyond words. Tuttle laughs too, and then he stands up and stretches an arm into the air. He opens a palm and with a swift snatching motion pulls down a bat.
“See how soft they are?” He flips the bat into an upright position and holds it out for me to stroke. The creature is about two inches long, brown and mousy. “Mexican free-tails are the least cute bats on earth,” Tuttle told me earlier. “But people always say, 'How cute,' when I show them one in my hand.”
“How cute,” I say to Tuttle now. The bat's face is tiny, wrinkly, and feels like velvet. Tuttle gently pulls open the wings to a span of about a foot. He holds it up in the fading light to show me the veins running through the thin, leathery skin, the four fingers and the thumb, which has a curved nail used for grooming, eating, gripping, and climbing up T-shirts. The hand bones are super-long and super-skinny; they remind me of skeletons and of evil.
I urge Tuttle into the cave. “Stay close to me,” he says. “Some of this guano is like quicksand. I once fell in up to my neck. What a way to go!” The guano is a soft brown color and about the consistency of flour. It blankets the floor in a layer at least six inches deep. It contains about a thousand species of bacteria and makes a superior fertilizer. Guano mining supports entire communities in some Third World countries, and it helps balance Tuttle's budget, too: Bracken Cave droppings are sold through a San Antonio nursery, and BCI receives a percentage of the profit.
We continue deeper into the cave. The smell of ammonia intensifies. The respirators aren't doing much. The slope of the cave floor becomes steeper, and our dim headlamps make out shadowy rocks on either side. At one point the passageway narrows, and our presence causes some bats to miscalculate their route. They whack into us and fall to the ground, or they whack into us and just cling. It feels like we're being pelted with wet tissues. We have to be careful where we walk, too, because bats are bouncing off our bodies and getting half-buried in guano under our feet.
One bat smacks into my back and scrambles up, higher, higher, until its creepy chiropteran toes are almost at my throat. “Merlin!”
“Get this bat off me!” I turn, and he removes the quivering creature. “Maybe we should get out of their way,” Tuttle suggests. “They're coming around the corner fast here, and they don't have time to adjust.” Tuttle tugs his respirator strap and shuffles in the guano. He laughs–whether at me or at the situation, I don't know–and heads for the side of the cave.
About 600 feet in, the temperature seems 30 degrees warmer, and the ammonia is twice as strong. But the bat action is a little slower, and it seems safe to stop and glance at the cave's ceiling. The Chinese say that bats sleep head down because their brains are so heavy. This isn't so; they sleep upside down so they can take off with the glide they need to gain flight speed. Swooping toward freaked-out homeowners waving brooms in the middle of the room is not their intention.
I scan the cave ceiling, but my lamp is dim, and it's hard for me to say what is lumpy limestone and what is bat. If I were here in early June with a more powerful headlamp, I'd see newborn bat pups clustered on the ceiling at densities of 500 per square foot. In pictures, pink, hairless babies are crammed so tight they make the cave ceiling look like a Rose Bowl parade float. The mothers apparently have no trouble locating and nursing their own young.
Something lands in my eye, and I give it a swipe. Tuttle turns and says, “Oh, you don't have glasses on.” He seems surprised. “Don't rub.”
“But I have bat shit in my eyes,” I tell him, blinking.
“That's not shit!” he yells, practically crowing. “That's piss!”
As a boy growing up in Hawaii, the son of Seventh-Day Adventists, Merlin Tuttle had no particular interest in bats. “At two, I collected monarch caterpillars in jars,” he says. “I knew when a chrysalis would open, and I'd call my parents to come and watch. We moved to California when I was five, and I got into herpetology. I dragged six-foot snakes into the house and terrified my mom. Then I practiced falconry. I had relationships with all kinds of strange animals.”
When Tuttle was 16, his family moved to Knoxville, Tennessee. In a cave about two miles from his house, he discovered a colony of gray bats, described as nonmigratory in the scientific literature. He and his father banded the bats, recaptured them a few hundred miles north, and proved the experts wrong. At the University of Tennessee, Tuttle photographed every frog species in eastern North America and then went on to earn his B.A. in zoology from Andrews University, in Michigan, and a Ph.D. in ecology and evolution at the University of Kansas.
A year after receiving his doctorate, Tuttle took a job as curator of mammals at the Milwaukee Public Museum. He did a lot of bat fieldwork and, in an effort to combat the animals' bad press, began photographing them in winsome poses. Alarmed over the decline of bat species–more than 50 percent of North American bat species are considered threatened or endangered–he approached the major environmental groups for help. “In Washington I was ignored,” he says. “They would give $300,000 for a panda, but they couldn't give $250 for a bat.” The Chiroptera, he learned, just weren't cute enough. Tuttle took matters into his own hands in 1982 by forming BCI and, in 1986, quitting his museum job and moving to Austin to run the foundation full time. Along the way, he married and divorced; his ex-wife remains a member of BCI.
Although Tuttle has published more than 46 papers based on his fieldwork and written several books, his expertise today is conservation, not science. He has a genius for raising money–BCI operates on a $1.2 million annual budget–and for reaching compromise with potential antagonists. In the bad old days, the Texas Department of Transportation might have taken a blowtorch to the bat crevices in bridges. Now the agency is funding a research project with BCI to figure out how to build bridges with more bat habitat. Tuttle has also changed the minds of farmers who want the “flying vermin” off their property and cavers who tear down protective gates over the entrances to bat caves. He got them to explore when the bats aren't in residence and to leave sensitive parts of the caves alone. He's now an honorary life member of the National Speleological Society.
“I do bats because no one else wanted to do it,” Tuttle says today. “It would have been easier to raise money to kill them than to save them.”
At the back of Bracken cave, about 150 feet underground, the bats are gone, and we take stock of our situation. The floor is more than eight inches deep in guano, and the surface is roiling with dermestid beetles, flesh-eating insects that prey on dead adults and fledglings that crash on their virgin flights. When a pup falls, it's reduced to bare bones within minutes. Fascinated, I start picking through the guano for tiny chiropteran skulls and skeletons, but all of a sudden Tuttle barks, “This mask isn't doing anything at all. Let's get out of here.”
He's breathing hard. The air is terrible. “This is a carbon-dioxide sink,” he says, sternly. “If you kept your head down near the ground for five minutes, you'd pass out.” My eyes are burning, and I can't get a full breath of air, but I'm too excited to leave. I put a handful of skulls in my pocket and reluctantly start to follow him out of the cave. The torrent of bats is now but a trickle. The respirators aren't worth a damn, and I'm worried about Tuttle's lungs. I start figuring out how many feet I'd have to drag his body through guano before fresh air revived him. I think about all those waivers I signed, never guessing it would be the bat man himself who succumbed.
Finally at the mouth of the cave, Tuttle rips the mask from his face and swallows great gulps of air. “Wow,” he says. “That was intense. I think the ammonia level was about 50 percent of what's lethal.”
We walk up the opposite side of the crater and sit down on a rock to regroup. Tuttle thinks that there will be another emergence tonight, that we haven't seen the last of Bracken's bats. He pulls a comb out of his pocket and goes to work on his head. “I can feel the mites crawling across my scalp,” he says.
Now that he mentions it, so can I. I flick a dermestid beetle off my arm and crush what I believe to be a mite. I'd like to scratch something on my face, but I think about where my fingers have been. I look at Tuttle, neatly combed but still sweaty and flecked with who knows what. “Do I have bat shit on my face?” I ask him.
“No,” he answers, “but would I tell you if you did?”
At 8:05, another emergence begins. It's slow at first but quickly picks up speed. Soon there are more bats than sky. Tuttle has seen thousands of emergences the world over, but still he seems transfixed. Sitting on a rock in the dark, he smiles beatifically. Later I ask whether his smile was of bored tolerance or old-fashioned wonder. “Definitely wonder,” he says. “I just love watching bats.”
“You're not sick of leading journalists through caves?”
“You're the first writer I ever brought in,” he says.
“During an emergence, you mean?”
“No, ever.” I'm surprised enough, but then he drops the bombshell. “In fact, that was the first time I'd ever walked in during an emergence.” The full horror of what we've just done now strikes me.
“You mean you've never walked into a cave during an emergence? You never pushed your way past seven million bats?”
“Hell no,” he says, grinning.
In that moment it becomes clear that Merlin Tuttle's dominant and true personality is the naturalist. The executive director has been left behind, back at his desk, a lowly creature of the day.
Elizabeth Royte, a frequent contributor to Outside, lives among little brown bats in Gotham.