until the question was resolved—all because of a tardigrade we thought we knew.
After observing eggs in Dr. Tenlen’s lab, I returned home to set up a new dish of pet tardigrades to study. I wanted to find one carrying eggs and began by collecting moss from the bottom of our back stairs, scraping it off the concrete surface. I didn’t search long before finding my first specimen, and I examined it closely. It was clear and I could easily see through it, and I thought I detected spherical objects inside. But surely, that was much too lucky? I turned up the power of the microscope, looked closer, and discovered that there were definitely eggs inside. They were enormous compared to the water bear’s body, and I couldn’t fathom how they all fit inside—and I’m not alone; scientists still don’t understand this about tardigrade development either. It was hard to get an accurate count because the tardigrade was constantly in motion, and as her body moved from side to side, the eggs squished back and forth.
I cleared a space in the debris around the water bear so I could see her more easily, but I was soon distracted by a much larger nematode thrashing off to the side. Easily ten times the length of the tardigrade, it soon moved into the center of my view. The unfortunate gravid tardigrade was bumped and thrown around by the larger animal, but her legs never stopped moving, and at one point she managed to grab onto the nematode, holding on like a cowgirl on a bucking bronco. After a few good bucks she was thrown off, and I used a tool to pull the nematode away from her so she could continue in peace.
Somehow the tardigrade ended up on her back with her little legs clawing at the water until she found a patch of debris and was able to climb, although with eight legs it looked more like gliding. But as her head lifted up toward me, she fell back again. Was the burden of those eggs too much for her? She spent some time scrambling on her back again, as if unable to right herself. I wondered if she could sense me. Every bump of the glass dish sent her tumbling, my touch having an earthquake-like effect on this tiny world. Even my breath rippled the water, and I had to hold my hand in front of my face to not disturb it.
I flipped the switch on the microscope, turning the backlight off and the overhead light on. Suddenly the little water bear turned from transparent to a translucent white color and I could see a patch of yellow on her. The yellow looked shiny, almost like she’d ingested tiny flecks of gold. I had a hunch and flipped the switch again. The gold appeared to be in the same place as her eggs—were the eggs gold? As I watched this endearing creature with her golden eggs, I thought with guilt about her living in the moss at the bottom of the stairs, being stepped on by us giant Homo sapiens. I suppose that’s nothing compared to a voyage to space, but I apologized to her anyway.
The Crow Roosts at Night
They come from the north. Every night as the sky darkens and the sun touches the horizon, hundreds of them fly over our house in one long, continuous line, a river that may change course to the east or west of us but always within view. They are the commuters of the sky, unimpeded by traffic lights and not limited by the routes of the road. They fly together on the same plane, but once in a while an individual will dive or swoop over a tree or over nothing at all, seemingly just for fun. They fly through the rain, the wind, the fading sunset. Many nights I stop what I’m doing to watch them. The half-closed curtains are still gripped in my hands when my mind and eyes flutter back down to earth. I can’t seem to help following them. They enchant me.
I can’t say exactly when my appreciation of crows began. It’s like a love that grows gradually but, once realized, feels like it has always been there. Every time I watch a murder of crows, as a group is called, whether they’re foraging along the lake’s edge or gathering in trees, my fascination steadily increases. It wasn’t long after we moved into our house in south Seattle one September that I first noticed their astonishing numbers. Truly, they’re hard to miss as they fly south over the Rainier Valley every night in the hundreds, perhaps thousands. I counted crows one evening while I was participating in the Great Backyard Bird Count citizen-science project. When I stopped at the end of my hour, which had started long before the crows began their commute, I had counted nearly three hundred in just one five-minute span of that hour. At the time, where they were going was a mystery to me.
When the weather turns cold and the leaves turn red, they start flying in larger numbers. When the bare trees sprout flowers and new leaves, fewer crows fly by while they spend their nights at their nests. However, every night in the autumn and winter all the crows around Seattle head to one of several roosts, where they gather to sleep after a day of foraging around the city. The roost on the north end of Lake Washington is one of the best known and perhaps the largest, with 10,000 crows on Bothell’s University of Washington campus. I wanted to experience that many crows in one place, so I headed to Bothell one January night.
After getting to the campus, I followed a winding path downhill from the parking garage, passing the playing fields and heading toward the wetlands. At the bottom of the hill I stood with the densely packed, bare trees of the wetlands on my left and the playing fields to my right. High on the hill towering over it all sat the campus buildings. My breath hovered in the cold air, and my toes began to tingle from the chill. Eager for the experience—and the crows—I had arrived well before dusk, so I waited, and waited. For three-quarters of an hour I scanned the empty skies all around and worried that the crows had changed their minds and gone somewhere else for the night. I saw not a single one. Eventually, after my toes had gone fully numb, a slow trickle of birds started to arrive from the south; but instead of gathering around the wetlands as I had expected, they continued right on past. Again I worried that they weren’t coming as I watched crow after crow ignore the campus and continue on a path toward some unseen destination.
But then, an hour after I had arrived, the flow of crows shifted and they started to fly in. At first a small stream of black silhouettes flowed in from one direction, and then more and more from several directions. As I watched the sky, the small streams morphed into wide rivers, flowing in from many directions, and I stood at the center of the confluence. Soon the sky was covered with evenly spaced crows, black as India ink against a deep blue sky. Lower along the horizon the crows were outlined against pink illuminated clouds. Instead of heading straight for the trees in the wetlands, where I expected them to roost, they flew to the tall Douglas firs on top of the hill by the campus buildings, five hundred feet away from me. There they circled, mingled, and landed unseen in the thickly needled branches of the trees, cawing all the while. As the evergreens filled, some birds started lining up along the roofs of the campus buildings while others chose the bare branches of deciduous trees. More and more continued to arrive, the sky never empty, the noise unabating.
At some unknown signal, even while the latecomers were still arriving, the crows began swooping down the hill, over the sports fields, and over the path where I stood, into the wetland trees. It was noisy, chaotic, and felt as if the sky were falling—and yet, despite the ruckus, there was a sense of order to the process. The crows didn’t all move at once, but in one slow rolling wave. The first to fly downhill landed in the trees at the south end of the wetlands; then birds slowly began filling up the trees northward. The sky became black with crows as they continued flying down the hill and into the trees. I felt like the sun, a static point with everything moving around me. Standing beneath the crows, I turned in continuous circles—I watched the latecomers still arriving from the north, then turned to watch birds flying down from the top of the hill, then turned again to watch them land in the leafless trees of the wetlands.
The crows’ flying formation is very uniform, not at all like the frantic starling murmurations that create art in European skies, or the flight of Vaux’s swifts that gather in the nearby town of Monroe and swirl in a giant funnel into an old chimney to roost at night. The crows space out—not too close together, yet not too far apart—creating an orderly, steady formation of flying bodies. As the crows continued gathering in the wetlands, I walked down the short boardwalk into the middle of the trees. Where organized chaos reigned outside, inside felt like complete chaos. The crows shifted about, fluttering from
