Slow Blues

On confronting the wonder and terror of nature

National Geographic Image Collection/Alamy
National Geographic Image Collection/Alamy

Late on a mid-June night, I stood barefoot in the yard between our house and a field of prairie forbs. Around me fireflies blinked greenish yellow—hovering, dodging, or posing on stems. The night before, they had drawn me to the window. Now, although I’d stayed indoors for most of the past six months, their light had lured me outside.

I wore clothing infused with permethrin, a potent tick repellent, and carried a canning jar and a swatch of cheesecloth for a lid. In minutes, a fast flasher flew into the jar. It signaled frantically as I brought it indoors for inspection. Under a magnifying light I saw its red-dotted head, its tan-striped back, nearly two centimeters long, and its antennae half that length. An ivory lantern spanned two segments of its lower abdomen. Lynn Faust’s Fireflies, Glow-worms, and Lightning Bugs (2017) told me that this specimen was probably a subspecies of Photuris versicolor—common in the eastern United States—but beyond that, I had no idea. Fireflies can be hard to distinguish without a microscope. Some are more easily identified by behavior, their blinking pattern, and the hue of their light.

I kept the beetle only long enough to examine it. I didn’t want it to miss another moment of its brief mating season, its brief adult life—a mere three or four weeks. Outside, the field was still alight. I uncapped the jar and shook it gently over the grass, but the firefly, probably petrified, didn’t leave. I set down the jar and left it there, assuming the insect would find its way out.


My second bout with Lyme disease had made me feel steamrollered, flat as a paper doll, limp as a deflated balloon. Some days I didn’t have the strength to sit at a keyboard and type. While I lay on the couch, my ears rang and pains stabbed at random—elbow to ankle to knee to hand. My heart would stumble, stop, suspend its work like a parachute waiting to open, then restart with a jolt.

My partner, David, and I had moved to the country 12 years earlier to try our hand at rural living and learn all we could about the land and its inhabitants. We’d made bricks from our own clay subsoil and built a house with them. We foraged and grew fruits and vegetables, heated with wood we cut from our forest, and experimented with prairie restoration. The life we’d crafted and loved required energy. Now I was walled off from that dream. I gazed out the window as the seasons came and went.

In attempts to be positive, I would ask myself, What can I do? Most days I had enough energy to hold a book and pen. So I read and took notes.


According to Faust, over 2,000 species of fireflies exist worldwide, but that number is a guess. A thousand more might remain unidentified. Some are scarce, found in shards of habitat—a single slope in the western Andes, a certain beach along the Delaware coast.

One type, Photuris caerulucens, nicknamed “slow blue,” lives only in a narrow band, 80 miles north of our place, that crosses the Mississippi River from Minnesota to Wisconsin. It glows turquoise for a second, dips as if to punctuate its message, then goes dark for about four seconds before signaling again. Slow blues were first identified in 1926, and researchers recorded sightings in 1970 and 2014, but the species is minimally documented. Few scientists have seen it. Entomologists I consulted at the University of Wisconsin–Madison weren’t familiar with it. Like me, they had been introduced to slow blues by Faust’s book.

On routine walks around our property, I have often encountered phenomena I could not have imagined: a live snake in an overhand knot in the middle of a deer path, a road carpeted with toad hatchlings, an oak’s canopy thick with raccoons that swung like monkeys and scarfed down acorns all morning. I would gape, lose my sense of time’s passage, lose myself. Each discovery reminded me that more discoveries were possible. If wanting more awe is a kind of greed, I was greedy.

I wanted to see the slow blues.

I hoped their range was poorly understood and that they lived farther south than where they had been identified. Sitting inside, I watched for them. I wished for a blue-lit beetle to rap on my window, but the only flashes I saw that June were yellow or green. I knew that awe depends partly on luck and partly on effort. To see a slow blue, I would have to venture beyond my yard.


Exhaustion had kept me indoors, but so did the fear of being bitten again. Our woods and fields were full of blacklegged ticks, which convey the Lyme disease bacteria, Borrelia burgdorferi, to other animals through their bites. I had often found the poppy-seed-sized nymphs or BB-sized adults on my skin after hikes. Some were crawling. Some had latched on. I would pluck them off or pry them out nonchalantly—until I got sick.

My doctor, a regional Lyme disease expert, had called our valley “the Midwest’s ground-zero” for tick-borne illnesses. A month before I went out to catch a firefly, a friend who lives up the road had been hospitalized with anaplasmosis, another of the six diseases conveyed by the ticks in our area. A second woman I knew was struggling to live after anaplasmosis caused her kidneys to fail. So far, I had avoided the deadliest pathogens. Still, I resented the one that ruled my life.

During my first bout with Lyme, in 2012, I had heard voices. Berating, shrill, insistent. I’d told the doctor, “I feel like I’m possessed.” He looked up from my blood test results and said, “You are.” He explained how the bacteria lodge in the heart, joints, and nervous system tissue and take different forms, making themselves more resistant to antibiotics. How the infection causes the brain to swell and how that leads to headaches, confusion, and behavioral changes. Lyme had made me no longer me.

Defiantly—very much like me—I told the doctor, “I’m going to beat this,” as I marched out of his office.

He called after me, “Well, I’m glad you have a good attitude.”

The Lyme bacteria’s possession dredged up memories of delusional parasitosis. For asthma, at 13, I had been prescribed adult doses of two drugs whose extreme side effects had included hallucinations and psychosis. I watched, horrified, as worms crawled out of my arms and legs. I was convinced I had lice. I pulled out my hair strand by strand, picked at my scalp, and woke my mom at all hours to show her proof—some imagined but very real arthropod pinched between my fingernails—that I was infested.

That phobia ended when I stopped taking the medicine, but thereafter, I was warier around insects. I cringed at any reference to lice. I inspected the sheets for bedbug trails. Then came Lyme disease, and with it, a concerning circularity: one form of psychosis caused by the bacteria’s effect on the brain is delusional parasitosis. I wondered if I was particularly susceptible. And if so, who was I to gauge whether my fear of ticks was overblown?


Slow blues, according to Faust’s book, had been seen over a marshy field with tamaracks in the distance, “between the now-small community of Bluff Siding and the village of Dodge, Wisconsin.” Bluff Siding is a bar, a bank, and a few homes overlooking a state highway that hugs the Mississippi River. Beside the river is a federal wildlife refuge. The refuge’s director told me slow blues didn’t exist there but suggested they might be found in the nearby Tamarack Creek Wildlife Area.

In early July, David and I drove to Tamarack Creek. On the way we passed industrial chicken operations with their block-long barns. The farmhouses and outbuildings became fewer and farther apart and the roads became smaller, until we were driving on a dirt track in the woods. Lightning flashed above the hills to our north. We parked in a turnoff hemmed in by trees. With alarming speed, insects enveloped the car—
mosquitoes, of course, and flies the yellow-gray of a tornado-brewing sky.

I sat still in the silent, safe interior. We could turn around and go home. But we had researched and planned the outing. We had driven an hour and a half to witness something astonishing. I put on a mesh jacket with a veil over my permethrin shirt, took a deep breath, and stepped out.


Years earlier, between my first and second bouts of Lyme, a friend told me that the disease had changed her personality. Once, she had been an extrovert; now, she was reluctant to go out. She no longer planned parties or volunteered at her kids’ school.

With my second case of Lyme I experienced similar inversions. Where I had been prone to impatience and haste, I was now slow and mild. I walked at a lag, pitching and rolling as if inside a bubble, while the horizon bobbed, too. I preferred sitting still. I could endure hours of small talk with dreamy, outsize interest. My lifelong insomnia disappeared. My memory was potholed, my reasoning sludgy. Also, just as I leaned on David physically when I was too weak to walk, I leaned on him emotionally more than before. I didn’t want to be left alone, not even for an hour.


Across the road from where we’d parked, David led the way into the bog, stomping down the reeds to clear a path. The sun was setting. The air was muggy. Thousands of fireflies blinked around us. They appeared as a web of tiny lanterns strung across that middle of nowhere. I felt daring and full of wonder, like the person I had been before Lyme, as I entered the marsh.

In an email exchange, Faust told me that a dozen species of fireflies probably live on my property, but I had distinguished only two types in my back yard. At Tamarack Creek, I recognized a multiplicity, each with a subtly different hue and pulse pattern. One type floated slowly as it glowed. Another dipped while signaling. But I saw no light that could have been called blue or bluish green. We stood among the reeds for hours, dwarfed by them, suspended between the pulsing lights. Then, in one moment, the bog went dark. In the next moment, all the beetles flared again. We gasped. Faust told me later that although synchronously flashing fireflies don’t live in Wisconsin, “they often seem to get one another going, with their enthusiasm causing periodic mass flashes.”

I detained a few fireflies in empty spice jars and examined them under a headlamp, but they looked just like the one I’d caught in our yard—too large to be slow blues and signaling yellow-green. Maybe we were early. Maybe we’d picked the wrong spot. How narrow, really, is the slow blues’ range? Are they rare or only understudied?

I’ve read that science has not even begun to decipher the mysteries of the commonest species, such as field mice, and that we have discovered only 14 percent of the species living on our planet. Often while hiking, I’ve thought, Why do we explore space or read science fiction when we’re surrounded by the bizarre and miraculous at home?


“Nervous awe and apprehension are born out of proximity and attention,” the poet Mary Ruefle writes in her essay “On Fear.” She quotes Barry Lopez: “On a day-to-day basis [Inuit people] have more fear. Not of being dumped into cold water from an umiak, not a debilitating fear. They are afraid because they accept fully what is violent and tragic in nature.” She adds, “The industrial world destroys nature not because it doesn’t love it but because it is not afraid of it.”

Allowing for the common, if problematic, distinction between “nature” and “human,” when I was a city dweller, I would drive hours to take solace in nature’s sensory extravaganza—the pine’s incense, the creek’s rush, owls calling at dusk. It calmed and revived me. But my noticing then was temporary, and being short-lived, superficial. After I moved to the country, nature dazzled me in different ways. I observed its systems at work, its rhythms and interdependencies. It seemed to want nothing from me. What a relief. I could wade through the river and wander all day on the other side without a smartphone, ID, or money. Nature didn’t ask favors or demand a response. But that was only more romantic imagining. Lyme disease made clear to me that nature has an agenda of its own, and a certain degree of wariness is wise.


A week after David and I stood in the marsh, I went slow blue hunting again, this time with my friend Liz. I had studied the map and found another tamarack swamp closer to Bluff Siding, where the entomologist Eunice Myers and her student Bernard Boland had identified and named the slow blues in 1926.

As we drove north, I watched the verdant hills and thought, peril. With every passing field and forest: tick, tick, tick, tick. How many millions were out there, lying in wait? One night in the swamp—bushwhacking through vegetation, standing still in the bug-thick air—seemed foolish in retrospect. It might have been all I could tolerate.

Studies with mice demonstrate that memories can be transmitted through generations and that specific phobias might be inherited. I welcomed this news. Maybe my shaking and sweating palms when climbing a ladder weren’t so irrational. According to my crude understanding of epigenetics, my symptoms might have originated in the refashioning of a 16th-century woman’s DNA as she watched her husband fall to his death from the chimney he was mending. Thus, her progeny’s DNA harbored a sensible fear of heights.

Genetics might have explained my acrophobia, but my fear of bugs was learned. I paid them little mind when I was a child. Even as an adult, I don’t fear them categorically. Rather, I fear their cunning and what they convey—not death so much as my involuntary metamorphosis into a person I don’t recognize. Although my journal indicates that in July 2017, I was feeling somewhat better, with enough energy to drive and walk and take notes, and enough lucidity to identify what I observed, I was not who I had been, and I didn’t know if I would ever return.

Philosophers and physicists say that repulsions come with equal attractions. But whether we fear or adore something, we are bound in a relationship with it. I wanted a better, braver bond with arthropods. The slow blues offered possibility. Also, inspiration. For this nearly forgotten species in its nearly forgotten habitat, a small blinking light was a matter of survival, an urgent attempt to carry on. A hopeful sign I needed to see.


I parked on the shoulder of a county road next to the swamp. It was 70 degrees at 10 p.m., dark, humid, and very still. The sky was cloudless, the Big Dipper garish above us. I wore my mesh bug suit and carried a camera, flashlight, notebook, and pen. Liz carried a butterfly net. I vowed to stay on the pavement to avoid ticks.

The slim, curving road looked similar to the road I live on but felt less friendly. Pickups rumbled in from a distance and blew past us. Each time one approached, we scurried to stand behind my car. A few motorists slowed. One man stopped and asked if we were okay, and we hastily answered, “Yes!” Once the headlights passed, we focused on the marsh again. We saw fast flashers, slow flashers, steady glows, and beacons that traced out long-division symbols. We counted seconds between the light pulses, and I wrote the timing in my notebook. Bullfrogs barked and grunted. Something hissed. Other beings plunged or plopped into the water.

After a half hour, we still hadn’t seen a slow blue. We reviewed what we knew of their preferred conditions. We decided again that the night was ideal. We debated scouting out another location to the west.

Then we turned to face the opposite side of the road, where the treetops we could barely make out indicated that the ground rose slightly. We stared through the dark. About 12 feet above the weeds, a bluish-green light was moving from north to south. It dipped slightly, went dark for four and a half seconds—I was counting silently—before lighting up again farther south. “That’s it!” we whispered. We held our breath. The tiny glow transfixed us. It drifted south, then switched off and on again in a pattern matching exactly what Myers and Boland had recorded and in an unmistakable turquoise hue, unlike anything we had ever seen.


In his writings about Japan in the late 19th century, journalist Lafcadio Hearn reported on the East’s reverence for fireflies. The Japanese followed the insects’ annual light shows. They celebrated, captured, and caged them. Some people believed fireflies to be the ghosts of fallen soldiers. Others used them in traditional medicines. According to Hearn, “Firefly-ointments used to be made which had power, it was alleged, to preserve a house from the attacks of robbers, to counteract the effect of any poison, and to drive away ‘the hundred devils.’ And pills were made with firefly-substance which were believed to confer invulnerability.”

But despite their onetime use as invincibility potions, many fireflies are toxic. Their bodies contain lucibufagin, a potent cardiac glycoside, a substance that can stop the heart. In addition to advertising their sexual availability, their light might serve as a warning to potential predators, such as bats, that not only do they taste terrible, but they are also poisonous. Ingesting one beetle could doom a salamander. More than a handful might kill a human. Still, I thought, maybe the firefly substance acts as a tonic in fractional doses. Maybe, like foxglove’s digitalis, another cardiac glycoside, it bolsters the heart’s contractions and steadies its rhythm. Had someone handed me those pills, I would have downed one.


Lynn had asked me to catch a specimen and take closeups of its front and back. So Liz jogged after the flying beetle with her net held high, as I hurried after her. But given this male slow blue’s altitude, there was little chance we could capture it. We searched for one of the females, which stay closer to the ground, but didn’t see any.

The area we jogged toward smelled like a carcass, and for the rest of the night, as we paced the road, gazing toward the upland side, the smell followed us. When a car passed, the stink rushed us and seemed even more putrid. The swamp’s night creatures rasped and groaned, while Liz and I joked about zombies lurching after us. At any moment they might clap their greasy claws over our mouths. We laughed to chase away our fears.

Slow blue males flickered a few more times, but never more than two simultaneously. Compared to the quickly flashing Photinus consimilis and Big Dippers, Photinus pyralis, on the other side of the road, Photuris caerulucens was elusive. Near 11 p.m., when we were about to leave, we saw one more. Or so we thought. I said to Liz, “Everything matches, but I haven’t noticed it dropping in flight.” Then the turquoise light swerved downward before being extinguished. Liz said to it, “Thank you for the clarification.”


Fireflies’ bioluminescence is called “cold fire” because unlike a campfire, it produces no heat. It’s the product of a reaction between luciferin and luciferase, chemicals named after lucifer, Latin for “light-bringing.” Luciferase, an enzyme, is also used as a marker in biochemistry, enabling researchers to trace certain bacteria, for example, through generations of organisms.

Scientists know that fireflies control their chemical signaling with precision but not why different species glow in different shades. They don’t know how quickly firefly populations are diminishing or how habitat loss and skies brightened by artificial light are affecting different species. Or why slow blues live only in a narrow swath of upper Mississippi River backwaters. What factors led them to evolve and thrive there? Algorithms can predict the bounds of a species’ niche, the only place it can thrive, given ideal temperature, humidity, the hours of light and darkness, food sources, predators, and pressure from other species that share its range. But no one has run the calculations for slow blues.

Also unknown is how quickly slow blues could adapt to changing conditions. If the tamarack swamp is drained for farmland, if the climate gets warmer or wetter than they can tolerate, will they evolve in time to survive in new circumstances? With their life cycle requiring two years underground as larvae or pupae, it’s unlikely they could migrate. Fireflies depend on very specific habitats. Their sensitivity makes them an indicator species. When conditions degrade, they’ll disappear before others.

Ticks, just the opposite, are highly adaptable. They have flourished and conquered new territory as North America’s temperatures have warmed. In 2018, the second year of my second bout with the disease, investigative journalist Mary Beth Pfeiffer published Lyme: The First Epidemic of Climate Change. Although the bacteria that causes Lyme has existed for millennia, Pfeiffer writes, “we have revived and empowered a sleeping giant”—thanks to warmer winters and earlier springs, “ticks have climbed latitudes like ladders; they have moved up mountains.” In fact, the spread of Lyme disease is one gauge the EPA uses to track climate change.

Reading Pfeiffer’s conclusions, derived from her interviews with experts worldwide about Lyme disease and the spread of ticks, could alter the DNA of even the most critter-bold explorer. For me, she confirmed a familiar dread. On viewing Monet’s Poppy Fields near Argenteuil in a museum, she wrote, “I can no longer look at such pastoral loveliness without seeing what lurks within.”


A year after I had stepped out to catch a firefly, a combination of pharmaceuticals, exercise, and diet had brought me close to normal functioning. To avoid ticks, I no longer walked into woods or fields. I wouldn’t brave the path to the prairie we’d planted, although I longed to see it and the bees and butterflies it must have attracted. Those were the ticks’ habitats. But I wouldn’t give up my garden. I planted rows of tomatoes, peppers, beans, greens, broccoli, pumpkins, potatoes, and popcorn. Gardening, I was my old self. I also restarted my running routine, shuffling up and down our road, careful to stay on the asphalt.

In mid-May, I found a tick dug into my scalp. It seemed impossible. What had I done wrong? Where had I crossed paths with it? I pulled it from my hair—a scrap of skin still in its mouthparts—and dropped it in a jar of alcohol. I tried to dismiss the incident. Given the volume of antibiotics I had taken over the previous 18 months, I imagined I was unlikely to contract Lyme disease again. But three weeks later, I was flattened, chilled, and feverish. Pain jetted down my legs and arms. I filled a new prescription for antibiotics.

The next month, I felt well enough to go outside and harvest some things, including a plastic bag full of kale. I used half the kale that day. Three days later, I took out the rest. At the bottom of the white bag was a black dot. A fleck of soil? I brought it close. A tick. I put on my glasses. Five more blacklegged ticks clung to the bag’s interior. All my precautions had proved useless. Most likely, I had been bitten in my own garden while wearing boots and clothes saturated with permethrin, my invincibility potion. As David tweezered the ticks out of the bag and into a jar of alcohol, I paced the kitchen behind him.

Some people in our valley live among ticks, get bitten, and don’t get ill. Some fall ill and shrug it off. They adapt to whatever changes it brings. They would never give up their place in this quiet, stunning landscape, this close-knit community. But after my third case of Lyme, with my habitat narrowed to exclude forests, fields, prairies, and even my garden, with my energy sapped, I admitted that maybe, to be the person I wanted to be, I would have to redefine my niche.

The unthinkable suddenly became possible: Leave the land. Get rid of the tractor, sawmill, chainsaws, beekeeping supplies, and gardening tools. Walk away from the house we had built. Break the news to friends with sadness. We could find a safer place to call home. But we might sacrifice, among many things, the potential for regular awe. I wasn’t sure I could make the trade.

Months later, after I’d regained some strength, after my workout partner said, “You got your fire back!” I thought, maybe I’m fully recovered. I told David, “We can stay.”

He pushed back. I couldn’t walk in the woods. Couldn’t mow. Couldn’t prune. Couldn’t garden. I was nervous about stepping off our walkway and into the grass.


Even after two years of struggling, I found it hard to admit that I was no longer who I had been. Days I never left the bed I kept secret. I only wanted to return to normal. If I had enough energy to wash dishes, I was thrilled. If I had more, I went running or baked bread. I would insert my old self into my new circumstances, even if the exertion set me back for another week. Then, at least for a while, I had denied Lyme’s control over me.

I couldn’t accept an unconditional exile from the natural world. I wanted to see the slow blues again. I wanted David to see them. I had new information about their habitat, a photo from an obscure entomology journal of the very “tamarack swamp in Wisconsin” where Eunice Myers identified the species in 1926. The photo was taken in 1970, but I imagined not much had changed, that ground too flood-prone to be plowed.

In July 2018, David, Liz, our friend Gary, and I drove north to find the swamp in the photo. At sunset, the clouds over the Mississippi were rouge and lavender stripes. The water was flat. A barge headed downstream. Gary pointed out islands where Native Americans had built effigy mounds and hills with bald crowns that were restored goat prairies. Together, we dreamed up techniques and conditions for experiments we might conduct to research the slow blues. In a lab—or no, in a giant tent over the grounds where they breed. Gary kept asking me about their lifecycle, but I couldn’t remember anything. When we stopped for gas, I handed him Lynn’s book.

We found the very spot where the 1970 photo was taken, matching the curve in the road, the 35-mph sign at its left edge, the gentle hill in the background. It was less than a mile west of where Liz and I had seen the slow blues the previous summer. We passed an old tractor pulling two empty hay wagons, then parked at the entrance to a dirt road marked with a modest “No Trespassing” sign.

I wore my permethrin garb and doused my ears, neck, and hands with bug repellent. I carried the butterfly net, although I knew I wouldn’t use it. My heart was in witnessing, not capturing.

The night was cooler than normal. Whether because of temperature or humidity, previous flooding, or some shift in the predator-prey balance, even the commonest fireflies were scarce. But near 11 p.m., on the upland side of the road, I saw one moving slowly about 15 feet above the ground. I thought that its lantern was a shade of blue—I wanted it to be—but the others contradicted me, and I wasn’t certain enough to insist.

Several pickups stopped. We talked with the drivers: the man who owned the land, who said it was okay for us to park there to look for fireflies, but didn’t understand why we’d want to; a man who farmed the ridgetop we faced and couldn’t say whether he had ever seen a blue-glowing firefly because he was colorblind; and a pair of citizen scientists like us, who were looking for bats.

An hour later, with no slow blue sightings, I gave up hoping to see what I had come for. With the others, I simply stood beside the bog and stared into the dark. I was aware of feeling contented in an imperfect habitat—outdoors, but on a manmade surface, not entirely safe from ticks and not fully immersed in nature. Happy, anyway, to be with people I cared about and who cared about me.

We packed away our flashlights, notebooks, and nets. We got into the car. But rather than drive away, we sat quietly, waiting, giving our quarry one last chance. Just then we were astonished by a brief, brilliant shooting star arcing across the southeastern sky where we had been watching for fireflies and where Mercury had been rising and falling all summer. It was so bright that I imagined I could have seen it from anywhere in the world. Maybe, maybe not. But as its arc faded, I felt sure that no matter where I went, I would experience awe, if coupled with fear, as long as I kept paying attention.

Permission required for reprinting, reproducing, or other uses.

Tamara Dean has written for Orion magazine and The Southern Review, among other publications. The author of the book The Human-Powered Home, she lives in Viola, Wisconsin. Her essay “Slow Blues,” published in the Autumn 2020 issue of the Scholar, was a National Magazine Award finalist.

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