The End of Night

by Paul Bogard

  But if wildness preserves the world, what preserves wildness? In his chapter from Walden titled “Solitude,” Thoreau hinted toward a possible answer.

  Though it is now dark, the wind still blows and roars in the wood, the waves still dash, and some creatures lull the rest with their notes. The repose is never complete. The wildest animals do not repose, but seek their prey now; the fox, and skunk, and rabbit, now roam the fields and woods without fear. They are Nature’s watchmen,—links which connect the days of animated life.

  Across the country from Walden and more than one hundred fifty years after Thoreau, Travis Longcore and Catherine Rich have created the Urban Wildlands Group in Los Angeles. Dedicated to “the conservation of species, habitats, and ecological processes in urban and urbanizing areas,” Urban Wildlands ranks light at night high on its list of concerns.

  “Back in 2002,” Longcore tells me, “if you had Googled ‘impact of light on wildlife,’ or ‘wildlife and night lighting,’ you basically got nothing except maybe birds and sea turtles.” In 2006, Longcore and Rich set about to change that by editing Ecological Consequences of Artificial Night Lighting, a collection that gathered the current research on light pollution and ecology. Along with articles on birds and sea turtles, the pair added pieces on bats, moths, fireflies, reptiles, amphibians, salamanders, fishes, and seabirds. Even so, most striking about this impressive anthology is that it remains remarkably thin—their section on “Mammals” has two papers, for example; their sections on “Fishes” and “Plants,” one each. For although, as they write, “natural patterns of darkness are as important as the light of day to the functioning of ecosystems… as a whole, professional conservationists have yet to recognize the implications.”

  With at least 30 percent of all vertebrates and more than 60 percent of all invertebrates worldwide nocturnal, and with many of the rest crepuscular, those implications are enormous. While most of us are inside and asleep, outside the night world is wide awake with matings, migrations, pollinations, and feeding—in short, the basic happenings that keep world biodiversity alive. Light pollution threatens this biodiversity by forcing sudden change on habits and patterns that have evolved to depend on light in the day and darkness at night. (In just one example, circadian photoreceptors—those same ones on which we humans rely—have been present in the vertebrate retina for at least five hundred million years.) Aside from crazy-looking ancient fish and their bottom-of-the-ocean ecosystems (and those of caves or soil), every creature on this planet has evolved in bright days and dark nights. None has had the evolutionary time to adapt to the blitzkrieg of artificial light.

  Significantly, Longcore and Rich make a distinction between “astronomical light pollution” and “ecological light pollution.” They define the latter as “artificial light that alters the natural patterns of light and dark in ecosystems.” Longcore says, “We had to do that, because the idea of ‘light pollution’ is very much an astronomy/astronomer focus. You could have a dark sky–compliant light—pointed down—and still do a lot of damage.”

  Light at night impacts wildlife in five primary areas: orientation, predation, competition, reproduction, and circadian rhythms. If we have heard anything about light at night and wildlife, we’ve probably heard about orientation. This is the problem of insects drawn to streetlights, of migrating birds being attracted to lit-up city buildings or communication tower lights, or of beach-born sea turtles heading the wrong way—toward streetlights and hotel signs—and ending up crushed by truck tires or plucked easily by predators.

  Introduce artificial light to a dark environment several billion years in the making and suddenly some species find themselves exposed to increased predation—and so reduce their foraging time. Introduced light means new pressures of competition between species, some of which adapt better than others. Artificial lights confuse reproduction cycles—the flashing attraction signs of fireflies, for example—or the internal circadian rhythms that synchronize the internal processes of birds, fish, insects, and plants, just as they do for humans. Beyond individual species, these light/dark rhythms also shape seasonal changes such as migration. Entire ecosystems shift as the length of light changes through spring, summer, fall, and winter. As one biologist told me, “We have levels of light hundreds and thousands of times higher than the natural lamp during the night. What would happen if we modified the day and lowered the light a hundred or a thousand times? Of course, the damage would be much worse. But it is a metric. You cannot modify half the time without consequences.”

  Some may ask why any of this matters for humans. But when we talk about ecological light pollution, we talk about the health of ecosystems, and no matter who we are or where we live, we live as part of one. Our ecological knowledge is really knowledge of our own health.

  “I’ve taught big intro classes where I would say, ‘Raise your hand if you can name three kinds of breakfast cereal.’ Every hand goes up,” Longcore says. “ ‘Raise your hand if you can name three TV sitcoms.’ Class of two hundred, every hand goes up. ‘Name three species of birds on campus.’ Uh… the black one? ‘Name three plants.’ Um… grass?” Longcore laughs. “I’m not making fun of these guys—this is the way we grow up in this country. We’re all urban. If somebody does have answers to those questions, they’ve grown up rural. People who grew up in a city have never needed this knowledge.”

  For Longcore, that bodes ill for the future. In his work with Urban Wildlands in Los Angeles, a city he calls “the poster child for light pollution,” he includes darkness as part of a larger ecological knowledge. “Unless we pay attention to nature in the places where people live, there will be no constituency for nature in the places where people don’t live,” he says. “People who grow up and never have the opportunity to go to a vacant lot and play with woolly bear caterpillars or raise a swallowtail butterfly from a larva or see the Milky Way just cannot have the sort of deep connection to land and nature on which our whole conservation enterprise in this country is based.”

  Every year of my life, I have come to this lake in northern Minnesota. In my earliest memories I am standing with my father on the dock watching the slow, straight line of a satellite through a sugary spread of stars; I am lying on the crunch-white snow-frozen lake watching the moon through my new handheld telescope. When I was a child in the seventies, night here would probably have ranked a 2 on Bortle’s scale, a “truly dark site.” I certainly remember stars thicker thirty years ago than now. I remember that really until the last ten years or so. While our darkest nights might still rank a 3, the local lights from Brainard, Longville, and even tiny Remer are pushing us toward Bortle Class 4. I hate to imagine where we may be headed.

  Still, this is the night I know best. From the end of our dock, from the edge of the woods, from our screened-in porch, I watch and listen, and on nights when the lake calms, I pull the ancient aluminum canoe from under the cedar trees and push it into water heavy like black oil, though clean and clear and cool. I back from dark shoreline shadows, paddling through stars, and raise a gold moon from the trees. Here the moon is as it ought to be everywhere: big, bright, beautiful. It moves through its seven phases (eight if you count “new”) with confidence, climbing from the woods behind our house and crossing over the lake at its own quiet pace. Its light is a gift from the sun, a reflection of the star shining on the other side of the world. Remarkably, the moon’s gray ash and rock reflect only 7 percent of the light sent its way, about as much as a sidewalk. But that’s enough light to illuminate the forest, bringing it alive with the scents and sounds of countless crepuscular and nocturnal species flying, hunting, singing, breathing. In ecosystems all over the world it’s the same: the dark provides cover, the moon provides light, and while the humans are home in our boxes watching our boxes, the nocturnal creatures keep this world alive.

  On the shore, on the dock, paddling on clear water—the lake is where I learned. Waiting for the moon, then getting out into the night.

  The
canoe gleams—I could read in this light. I’m glad to have my Twins cap, pulling it down to shield my eyes as I paddle to the middle of the lake. Perseus emerges over the horizon, the Summer Triangle overhead. Lying back, I let the canoe rotate away from the moon. A splash startles me, a fish for sure. Then silent and still again. As I drift over the sandbar something scrapes the bottom of the canoe. “Weeeeeeeeds!” we would cry as kids. A freaky sound, and I nudge the canoe into deeper water. Everything very quiet, very still. And then the sound of a truck on Highway 6, a mile away, the sound as it floats around the flat water amplified, for miles coming and miles going, sputtering and puttering and passing its gas from one horizon to another.

  From shore, the barred owl’s hoo-hoo, hoo-hooooo, in the water, frog songs and fish jumps. The lake pulses with life. I hear bubbles that have risen from bottom weeds burst, imagine walleyes and northerns cruising beneath the canoe. A loon calls, a plaintive wail so mournful that if you didn’t know better you might go for help.

  We swam with flashlights one summer as kids, my cousins and I. Straight beams of white light swording through black water. We had heard the story of two friends snowmobiling the winter before, of their going through the ice, drowning. I used to envision my beam finding skeletons still strapped to swallowed machines.

  Jorge Luis Borges wrote, “I think one should work into a story the idea of not being sure of all things, because that’s the way reality is.” There is so much unknown in the lake’s wild night. The way owls hunt and fly without sound in the dark. The way wolves drift through the woods like smoke, evaporating at the first hint of morning light.

  “Yeeeeeeeeeeeeeeeeaaaaaawwwww.” The owl behind our house releases this long yowl, a descending tremolo at the end, then launches into several hoo-hoo, hoo-hooooooooos, and is answered by a deeper-voiced owl from down the shoreline.

  I sit listening to these two owls going back and forth behind me as though they will never stop. Then, this is what I do: With two strokes I turn the canoe toward shore and set the paddle down. Two strokes as quietly as I can, and the owls stop. They hear me, back in the woods on their branches in moonlight.

  “You can hear better in the dark,” says Joseph Bruchac, a Native American writer and teacher, when I ask about our senses at night. “A Cherokee friend of mine told me about something he was taught as a child, part of traditional Cherokee culture, called ‘opening the night.’ What you do is you go out into a dark place, it could be on your back porch in the old days, and you sit, and you listen to what’s around you in a very close circle, within arm’s length. You concentrate on that, then you double the circle, and hear everything beyond there. And you keep doubling that circle. And he said it would reach the point where at night you could sit down and hear things a mile away.”

  Talking with Bruchac, I think of John Himmelman telling me he likes to “tune in to” one particular cricket or katydid (“leaves-with-legs,” he describes them), like singling out one particular instrument in an orchestra. Author of Cricket Radio: Tuning in the Night-Singing Insects and several other books, Himmelman lives on five wooded acres and says, “I like being able to pick out the individual callers. It takes me away, extending my consciousness beyond where I am. Almost like I’m taking a tour of the night forest.”

  Himmelman says he notices the sounds of crickets… and of katydids, of singing birds and chorusing frogs, even of “caterpillar-droppings bouncing off leaves in the summer, and the rustling in the understory along woodland edges… because I have consciously tuned in to them… since I was a very young child.” He often leads tours to listen to night-singing insects and says people are delighted by what they hear. “They’re so used to being inside, it’s already an adventure when they show up. We don’t even get started until after nine p.m.,” he explains, and he says that the adults are as excited as the kids. “The most common thing I hear is, ‘I never realized these were out here!’ If I only find one or two things, that’s a slow night for me. But for these people who have never really gone on a night walk, they’re thrilled.”

  Walking on Cape Cod in the 1920s, the American writer Henry Beston mused on “those trillions of unaccountable lives, those crawling, buzzing, intense presences”:

  It occurs to me that we are not sufficiently grateful for the great symphony of natural sound which insects add to the natural scene; indeed, we take it so much as a matter of course that it does not stir our fully conscious attention. But all those little fiddles in the grass, all those cricket pipes, those delicate flutes, are they not lovely beyond words when heard in midsummer on a moonlight night?

  Himmelman tells me that insect song has been around forever; that fossils of sound-producing Ensifera (katydid and cricket) forebears date back two hundred fifty million years. As such, it’s a sound humans have always known as part of their nights, a sound Himmelman explains as that of “two hardened wings being rubbed together, multiplied many times over.” Crickets and katydids sing at night to avoid daytime predators, and sing in chorus to disguise their location from nighttime foes. “A singing insect is compelled to sing,” Himmelman writes. “To silence it, you’d have to tie its wings behind its back.” But instead, he suggests, think of these sounds as “a gift we humans have been given. We can take pleasure in hearing such sounds. It doesn’t always matter why that sound is being made, or who or what is making it. Sounds can enrich our lives.”

  The same is true of scents, and the night air is rich. During the day, rising warm air carries the earth’s scents away, but as night temperatures cool and night winds calm, those scents stay close to the ground, waiting like messages for those creatures who can receive them. Pollinators, scavengers, hunters, and prey—the scents from the earth are maps of their nocturnal world, directing travel, pairing species. Saying, Come get me. Warning, Stay away. Even for we olfactory-limited humans, night air holds overwhelming power, with scents that can send us instantly across countries and oceans, and back through time.

  In the house where I grew up—with my room on the second floor, in the northwest corner—I set my bed near the windows so that, with the lights out, I could lean toward the screens, close my eyes, and imagine the lake, or my grandparents’ house, or even some unreachable place from the past or the future or inside myself—I didn’t know, but I wanted to be there.

  Fall nights spoke of fires and wood smoke, my parents’ black Franklin stove burning the split lake logs of birch and oak, the smoke of summer infused in autumn, drifting through the neighborhood. In winter, the air told of snow and cold already in forests and lakes across the border, too soon coming our way. In earliest spring I would open the window an inch and breathe a fresh wet chill, the coming season somewhere south, red cardinals and rust-breasted robins moving their songs toward us some each day. I would press my nose near and could barely stand it—the scent so full of intoxicating promise I would have to pull away.

  For moths, the night’s scents mean everything—life instructions, keys to mating, perhaps even their muse. Mostly we mock their attraction to flame, to fire, to electric light. Mostly we know them as we know any of night’s wildlife—dead, at the base of our light fixtures, under a rolled magazine. That we can be so quick to kill moths is ironic, for they do so much to keep our world alive. While each individual moth lives only a week or two, collectively they pollinate some 80 percent of the world’s flora. Estimates of moth species range from 150,000 to 250,000 worldwide, so no matter where we live they share our lives.

  While some moth species can have serious costs for agriculture, only 1 percent of moth species give the rest a bad name. The others are harmless. But because they come out at night, we ignore them, fear them, squish them without thought. And in their attraction to light they suffer tremendous losses, night after night. In addition to their irreplaceable role as pollinators for the flowers, bushes, cacti, plants, and trees we benefit from and enjoy, moths are a vital part of ecosystem food chains. While those species that eat moths enjoy a momentary benefit from
moths being attracted to light—the Luxor beam comes to mind—those lights actually act as a vacuum, sucking such protein from the ecosystem, the food and fuel on which creatures further up the food chain rely.

  Ecologists are only beginning to understand the long-term impact of this phenomenon, but Himmelman calls a world without moths “bleak,” and not simply because of their economic or utilitarian value. Of the luna moth, he writes:

  Its beauty is ethereal and its nature ephemeral; it doesn’t live much past a week or two. It emerges from its cocoon in the leaf litter, then mates and lays eggs within the first forty-eight hours. Then it has the rest of its nights with nothing to do. No purpose. It doesn’t eat. It doesn’t drink. All its energy comes from the leaves it ate as a caterpillar. That energy is finite and cannot be replenished. It is like a toy airplane powered by a twisted rubber band. Once the rubber band unwinds, the propeller stops turning and the plane falls to the ground.