The End of Night

by Paul Bogard

  Because this happens at night, most of us never see. This moth, with its colored wings and long tail, a nocturnal butterfly in the light of the moon, has no purpose as it shares our world while its energy runs dry. No purpose, you might say, except for beauty. If their beauty was merely utilitarian, you would think after copulating they would just die. But instead they stick around for a few nights. I like the thought that this nocturnal butterflylike creature is out at night fluttering around for no apparent reason except to make this world more beautiful.

  Once at the lake I found a small brown moth in my bedroom, and my first thought was to squish it. But instead I stopped and watched, four wings, two on each side, tiny eyes and antennas. A friend who studies moths describes these small moths with their sloped wings as “fighter jets,” this one resting on the tarmac of my bedroom door. And I found that this tiny flier can do things fighter jets can’t. When I cupped the moth to my chest and released it into the night, it rose to reveal an autumn-orange underside. It was a member of the Catocalas, or underwings, group, and—as other moths have evolved “eyes” on their wings to mimic predators and bright wing colors to say Toxic!—this underwing color likely evolved to startle predators. But instead it startled me, a hidden flame in the lake’s wild night.

  I remember one summer when the local news was of a collision between a timber wolf and a motorcyclist. Both were dead, the sixty-two-year-old man thrown into a roadside ditch, and the wolf of unknown age found under the bike. They must both have been surprised, the meeting taking place before dawn, not far from the lake. I might have heard the wolf the night before, might have heard the motorcycle as it growled by. I don’t know if the man was wearing a helmet. The wolf was wearing its summer coat, and perhaps, having just stepped onto the highway, had paused without intending to. Some scent caught its nose, or some sight caught its eye—the rose pulse of the waning crescent moon just above the horizon, perhaps—and so this wolf paused on the highway when, on any other morning, he would have continued trotting across the blacktop, the broken yellow line, disappearing back into pines and oaks, the woods called home. And the man on the machine would have come flying around the highway’s curve in time to see the gray hind legs, the great silver coat, the glowing amber eyes. Instead, maybe the man was looking at the moon, too, wondering why it was still up in the morning. Maybe that was his last thought. Or maybe that last thought was, My gosh, what beauty.

  Every day in the United States alone more than a million birds and animals die on the nation’s roads and highways, and because so many species are nocturnal or crepuscular, more than half of this carnage occurs at night. These nighttime collisions are incredibly costly to humans as well. In fact, at least statistically, deer are far more dangerous than mountain lions or bears or, certainly, wolves. Every year in the United States more than two hundred people are killed in deer-vehicle collisions, the most dramatic result of the more than one million annual deer-vehicle collisions that cause ten thousand personal injuries and cost more than $1 billion in damages (and, of course, the deer do not fare well, either). Studies show that increasing highway lighting to reduce such collisions is ineffective, and actually makes it far more difficult for wildlife active at night, at dusk and dawn, to avoid collisions. Animal eyes that see so well in darkness or dim light—blessed with more rods than cones—are blinded by our headlights and streetlights. “On the issue of designing highway lighting to minimize road kill mortality,” writes Paul Beier in Ecological Consequences of Artificial Night Lighting, “our knowledge of mammalian vision is sufficient to conclude that, from the animal’s perspective, less is better.”

  Less light on our roads, fewer streetlights and not so bright, is not only better for wildlife but safer for us—we drive slower and pay more attention when we have to rely on our headlights.

  But how to do with less light on our streets and highways? One innovative concept comes from a design cooperative in San Francisco called Civil Twilight. Their award-winning idea: streetlights that respond to moonlight, or “lunar-resonant streetlights.” Relying on LEDs and highly sensitive photosensors, they would allow the level of brightness from the streetlight to balance the level of light from the moon. On nights when there is no moon, or just a crescent, the streetlights would provide enough light for pedestrians and drivers. On full-moon nights, the streetlights would dim to barely on. Civil Twilight estimates that their idea could save more than three-quarters of the money spent on streetlights, as well as bring the ambience of moonlight back to our streets.

  The idea borrows from an old one. In the eighteenth and nineteenth centuries, street lighting was still intimately tied to the changes in seasonal light and the moon’s monthly phases. In Paris, even after the advent of gas lighting in the 1840s, two kinds of lanterns were used, one that burned all night, and another that was lit only when the moon in the streets didn’t offer enough light. Even into the early twentieth century, many municipalities planned their lighting schedules in relation to the moon. Long before Paris was the City of Light, it was, as every city in the world, a city of moonlight.

  And to enchanting effect. In Nocturne: A Journey in Search of Moonlight, James Attlee explains, “Just as in a black-and-white photograph, the lack of colour visible by moonlight makes the architectural structure of the landscape more apparent.” Goethe saw this while touring Rome in 1787:

  Nobody who has not taken one can imagine the beauty of a walk through Rome by full moon. All details are swallowed up by the huge masses of light and shadow, and only the biggest and most general outlines are visible. We have just enjoyed three clear and glorious nights… This is the kind of illumination by which to see the Pantheon, the Capitol, the square in front of St. Peter’s and many other large squares and streets.

  It’s an effect we no longer experience today. Too often in modern cities the moon, overwhelmed by artificial lights, makes its crossing unnoticed. And so we forget the wild beauty of this natural light, or worse: We never miss it because we have never had the chance to learn.

  Tonight in Austin, Texas, I’m standing on the Congress Avenue Bridge with the chance to learn from Merlin Tuttle, the world’s foremost expert on bats. We are here at twilight to see the emergence of between 750,000 and 1.5 million Mexican free-tailed bats from under the bridge, a wild sight in the midst of a city of a similar number of humans. Founder of Bat Conservation International (BCI), Tuttle has worked for more than thirty years around the world to raise human appreciation for these amazing mammals. In the world of wildlife conservation, the name Merlin Tuttle means bats.

  In part because we so identify them with darkness, bats have suffered immeasurable persecution at human hands. This persecution has been and is motivated by irrational fears of bats carrying rabies (which only one half of 1 percent do); bats tangling themselves in human hair (which, for an animal whose echolocation can detect a single human hair, is not going to happen “unless you’re sporting a head of cucumber beetles,” warns one Ohio Department of Natural Resources website); or bats “attacking” humans (Tuttle says in his forty-year career he has yet to see a bat be aggressive toward humans). In the rational world, bats clear our skies of mosquitoes and other pesky insects while pollinating the flowers and fruits we enjoy—tasks that have enormous benefits, economic and otherwise, for humans. Yet around the world—and nowhere more relentlessly than in the United States—colony after colony of bats has been destroyed by humans wielding guns, fireworks, dynamite, flames, napalm, poison, tennis racquets, hockey sticks, and other weaponry, simply because we fear these small, nocturnal flying mammals. In just one example from the early 1960s, the world’s largest known bat colony, in southern Arizona, was reduced from thirty million to just thirty thousand, shotgun shells littering the hills outside the colony’s cave.

  But with his tireless work on their behalf, Tuttle has made a difference. He shares the story of a Tennessee farmer agreeing to let him study the bats in a cave on the farmer’s land but telling him, “While you�
�re in there, kill as many of them as you can.” When Tuttle found the cave floor littered with the discarded wings of potato beetles—the farmer’s main pest—the farmer changed his mind immediately about the bats. Tuttle says that when he first began working with bats and gave presentations, he’d have to spend the first ten minutes of his talk simply debunking myths. Now, he says, he often gives talks during which no one bothers to ask about rabies, or vampires sucking their blood, or the chances of a mass bat attack on an unsuspecting American city.

  When Tuttle first moved to Austin in 1986, there probably were some people who thought a mass bat attack was imminent. The Congress Avenue Bridge was only six years old, and a few hundred bats had discovered that its understructure made a perfect roost. Their arrival excited some in the Austin public to call for the bats’ eradication. “There was a USA Today headline that read, ‘Hundreds of Thousands of Rabid Bats Invade and Attack Citizens of Austin,’ ” Tuttle tells me. “The Austin American Statesman had one that read, ‘Bat Colony Sinks Teeth into City.’ But now that same paper has a bat mascot, and a bat hotline you can call and get information about when the bats are flying.” Tuttle laughs, saying that now, when people want to write stories about those days, they can’t find anyone who will admit to calling for the bats’ eradication.

  Tonight as we wait, a crowd of all ages gathers behind the bridge railing. On the Colorado River below, several small tour boats bob with rows of expectant faces, and individual kayakers ready their waterproof camera gear. At one end of the bridge, a billboard advertises Bacardi tequila, prominently featuring the company’s bat logo. Close by, bat watchers are greeted by a large black bat statue and a sign proclaiming the Congress Avenue bats to be the “world’s largest urban bat colony.” And every so often, a “world’s largest” waft of “aroma”—the distinct scent of bat guano—comes rising from under the bridge, as though the bats are letting us know they’re getting ready.

  The tiny percentage of bats that carry rabies wouldn’t seem to warrant human hatred toward them. Tuttle tells me that no group of mammals has been more intensively studied for disease issues than bats, and they still turn out to be among the safest animals around. “I rest my case here in Austin,” he says. “The public health people said these bats were going to attack people and give them rabies, and the city almost eradicated them. And I said, ‘Look, they have value, and if you leave them alone they’re going to leave you alone.’ And close to thirty years later, we’re still waiting for that first bat attack to occur.”

  One of the ways Tuttle has changed people’s perceptions of bats is through photography, a skill he taught himself out of necessity. After writing a feature story for National Geographic “talking about what really neat animals bats are and how they’re harmless, contrary to people’s superstitions,” Tuttle says he went to Washington to review photos for the article and found the only photos the magazine had were of snarling bats—a self-defense posture provoked by blowing in a bat’s face to get it to open its eyes. The photos made the bats look terrible—“anything but something you’d love.” Tuttle told the magazine, “You know, you wouldn’t do this to any other kind of animal. People would have a fit if anything was provoked before they were photographed.” In the years since, Tuttle’s bat photographs have been featured all over the world, photographs that show floppy long or stubby ears, happy eyes, and black, almost see-through wings—in other words, showing that bats are nothing you need hate.

  Because there are more than a thousand species of bats—fully one quarter of all the mammal species on the earth—it’s hard to generalize about them, but that doesn’t keep me from asking Aaron Corcoran to do just that. “Bats are amazing, amazing creatures,” says Corcoran, a doctoral student studying bat-moth relationships. When I ask what he thinks most amazing about them, he laughs. “You’d have to listen for an hour. I don’t know if there is one thing. What comes to mind first would be just their sensory environment and the world they live in and the speed at which they respond to the environment. An echolocating animal will make anywhere from ten to two hundred echolocation pulses per second, and in the tenth of a second or less between when a sound goes out and when the bat listens to the echoes, it will take all the information, process it, and make a decision about what to do next. The temporal scale they’re working at is just incredible. Some of them are making sounds that range from 20 kilohertz to 120 kilohertz, which is six times our range of hearing, in three-thousandths of a second. And then they will hear that sound come back, and just from the properties of that sound tell the texture of an object, how far away it is, and the direction. It can determine very quickly if it’s a prey item it wants to chase after, or one it doesn’t want.”

  Donald Griffin, who began working with bats in the late 1930s and is credited with discovering echolocation, said that studying bats was like visiting a magic well. For sixty years, he kept going back to that well, and it never stopped offering new discoveries.

  One of the most remarkable stories about bats is the way that, in a cave home to a million or more, a mother can leave to feed and then return to find her own offspring amid pups packed two hundred to five hundred per square foot. According to Tuttle, recent research shows that bats have the same long-lasting social structuring as higher primates and elephants. Researchers have also found that even though the bats they studied went to completely different winter hibernating sites for half the year, they still recognized each other as individuals and had different levels of “friendship.” “You can call it whatever you want to call it,” Tuttle says, “but it’s probably little different than what we have. They’re pretty smart.”

  When the bats begin to emerge into Austin’s night in spurts and long flows, a just-audible cheer goes up and people—adults included—actually giggle at the sight. I can tell that Tuttle, having seen the emergence so many times, isn’t that impressed. (“It should be getting better,” he says.) But I get excited seeing one bat, so the ebb and flow of thousands have me whispering amazement. I’m seeing an animal, despite all human attempts to deny it life, come swirling from under a bridge in what seems like joyful flight, and I’m saying to Tuttle, “This might not be good, but it’s breathtaking.” He laughs. “When it’s good, it’s one of the wildlife sights of the world. You can see the columns for miles.”

  Hundreds of thousands of Mexican free-tailed bats emerging from under the Congress Avenue Bridge in Austin, Texas. (© Randy Smith Ltd.)

  The bats swirl in curling black funnels off toward the eastern horizon, headed toward agricultural lands to feed on corn-ear and army-worm moths, which Tuttle tells me are billion-dollar-a-year pests for the Texas economy. In fact, a recent study shows insect-eating bats are worth at least $3 billion to U.S. agriculture alone. As they spend the night feeding, bats eat literally tons of bugs, saving farmers the cost of pesticides. But the $3 billion figure is actually quite conservative, and the savings may be more than $50 billion, as the study omitted many downstream costs to pesticide use, such as human health problems and difficulties related to the development of resistance in bugs. All around the world, bats pollinate fruits and flowers and eat pests that otherwise would devour crops. Ironically, the enormous benefit they bring to human societies is probably proportional to the hatred and fear with which those same societies regard them.

  Despite the advocacy of Tuttle and others, bats still desperately need help. In addition to continued human harassment, millions of cave-dwelling bats east of the Mississippi have been wiped out by a plague of white-nose syndrome—a disease named for the white fungus that appears on the muzzles and wings of infected bats—and migrating bats have no defense against wind turbines, which threaten to kill at least sixty thousand a year by 2020 in the United States alone. Unlike birds, which typically die from direct impact with turbine blades, bats are killed by a condition called barotrauma, essentially a version of “the bends” suffered by scuba divers. The rapid drop in air pressure around the wind turbine blades causes bats�
� lungs to burst. Lights may play a role in these deaths, as bats must fly close to the blades to suffer barotrauma, and some species will be drawn to the insects attracted to the turbine lights. If that weren’t enough, European studies show that the glare and trespass of artificial lighting diminishes bat habitat and disrupts their already stressed lives. While scientists struggle to figure out white-nose syndrome and wind turbine deaths, controlling our light would be an easy step toward helping these creatures that do so much to help us.

  Tuttle’s devotion to helping bats continues to take him around the world. When I’d first reached his house at the start of the evening, he had been memorizing sentences in Spanish for an upcoming talk in Cuba. (He was working on “Newspapers are still, despite all we’ve learned about bats, publishing stories about how dangerous they are” when I arrived.) At the end of the night, after we leave the bridge, we will drive up the road to look for red bats hunting moths above the lights of the Texas state capitol—the bats devouring the moths in midair, moth wings fluttering to rest at our feet. Tuttle brings his “bat detector” along, a kind of transistor-radio-like device that sputters and beeps and buzzes as it translates bat activities. As we stand listening and looking up into the night, a young woman walks by with a smile, nods at the bat detector, and says, “You guys talking with the bats?”

  For Merlin Tuttle, the answer has long been yes, in whatever language it takes.

  At twilight on a clear night at the end of June, I park in a Cape Cod National Seashore lot, make my way through hordes of gnats (a woman coming from the beach says to her friend: “Jesus Christ, these gnats are like rabid foxes”), and descend to the sand and the sea. I love the feeling of striding out to meet the night, and this is a night I have been looking forward to ever since reading Henry Beston’s The Outermost House. Shore fires ahead and behind, birdcalls all around, the pump and splash of crashing surf, the gathering curtains of dusk over the ocean to the east. Finally, I’m walking Beston’s beach.