Most mornings I awaken to the territorial song of a whip-poor-will. Wait a minute! you might say, if you have some familiarity with this bird. The whip-poor-will rarely performs its namesake song outside the spring mating season. And hey… (you may add suspiciously) whip-poor-wills winter along the Gulf of Mexico and in Central America. They’re hundreds of miles from your frigid Minnesota home in winter! What’s the story, Petersen? The truth is, I cheat. My whip-poor-will waker-upper comes from an alarm clock.

During the spring breeding season, local wild birds often make my electronic whip-poor-will redundant. Thanks to its high latitude, Minnesota’s June sunrises take place as early as 5:30 a.m. Humans may have allied dawn and birdsong, but birds don’t seem to consider this such a firm contract. More than two-dozen songbird species nest in our neighborhood, and many appear to consider it slothful to wait until sunrise before singing. Some start as early as 4:00 a.m.

In the heart of winter I miss that avian chorus, however inconvenient its timing. Some birds remain here year-round, to be sure. Last year my son’s kindergarten class studied winter birds. Over dinner one evening, he proudly informed me that birds only migrate if they can’t find their usual foods (such as insects). We enjoyed learning to recognize some of the species that frequent our yard in winter: black-capped chickadee, bluejay, American goldfinch, dark-eyed junco, American crow, Northern cardinal, white-breasted nuthatch, and several woodpecker species make up a partial list. (This year we have even been seeing American robins, historically the indicator of returning spring.) Each morning, as I watch the sunrise from the kitchen, I notice the smaller birds flitting to our feeders and heated birdbath from hidden perches among the trees and shrubs. In the depths of winter their business is conducted in almost unnatural silence. Later in the morning, if the day is warm enough, the birds’ voices begin to reach me through the windows of my office—impatient squawks of bluejays; burbling chatter from chickadees; stern-sounding ticks made by foraging juncos. The sound comes in waves throughout the day as winter flocks of each species move through their territories in search of food. As evening falls I resign myself to another long stretch of silence, and I look forward to the cheery, tri-toned wake-up call of my whip-poor-will alarm.

This morning, through the cottony strands of sleep still tying my mind to the dreamscape, I realized that something was different with my “alarm.”  I woke to a sound far more resonant and insistent. A sidelong glance at the clock—6:10 a.m.—told me that this sound had not come from my alarm, which was not due to go off for another fifteen minutes. The sound came again. Who-ha-hoo-o-o! And within a few heartbeats, the great-horned owl’s sonorous call was repeated. I smiled and pulled the blankets closer around me as I listened to the long concert.

Great-horned owls are the first of our winter-resident birds to nest, and hooting becomes most intense just before the female lays eggs. Devoted mates, the owls form pair-bonds that endure for years. Rather than migrating, the pair establishes and maintains a permanent territory. (Localized winter food shortages may break this pattern, prompting temporary southerly movements, or irruptions, toward better food sources.) Territorial boundaries are reaffirmed each autumn—just in case any young upstarts have showed up in search of a home. The big birds become unusually visible at this time, often perching on exposed branches or hunting in the afternoon. Great-horned owls also become more vocal in autumn. One of my most vivid memories from my son’s infancy is of sitting in his room during feedings in the middle of the night. As we rocked together in the chair by the window, the sleepy silence was often broken by the calls of a great-horned owl. Before putting the baby back in his crib I frequently stood at the window, swaying gently as I searched for the owl’s dark silhouette. The bird’s preferred hooting spot was the highest bare branch in the neighbor’s yard, from which his voice carried far across the trees and lake. Though years have passed, the sound of owl-song still evokes those nights with my newborn son.

It’s hard to say exactly where the owls’ nest is located. Great-horned owls don’t construct nests as some raptors do, but take over the nests previously occupied by crows, other raptors, or even squirrels. These might be stick nests, somewhat exposed in a winter-bare deciduous tree, or hollows in an aged tree. Around our property are many choices. I’ll be keeping a close eye on several old maple and oak trees at the bottom of the meadow. Each autumn we’ve seen great-horned owls perched on their branches or on the ground nearby. And one morning this past January, after a storm, my son and I were thrilled to notice a large set of wingprints in the meadow’s fresh snow—evidence of the bird’s attempt to capture prey on the ground.

Whatever the location of the nest, several tiny owlets will hatch in mid-March. By early May, as frogs begin to call along the lakeshore and the trees in our orchard reach full bloom, the fledgling owls will be ready to fly beside their parents and begin their education in the ways of the owl.

If the female has already begun to lay her eggs, this morning’s round of owl-song may be the only concert we get. But soon enough the mornings will ring with the din of eager songbirds. For now, my whip-poor-will alarm provides sufficient daily affirmation of one of the first realizations I made when becoming a naturalist: Listen for birdsong every day, just because you can.

I'm standing on the coastal trail just west of San Francisco's Golden Gate. Fog obscures most of the famed structure, though now and then a blazing patch of red is revealed as a gust of wind pushes aside a corner of the low-lying cloud. My goofy grin and slightly elevated heart rate are reminiscent of the symptoms I used to experience on a promising second date. I indulge the emotions, for they are familiar and sweet. In a way, this city is like a long-lost lover. Although my new sweetheart—Minnesota—is also full of charms, some part of my heart will always remain here.

The Golden Gate Bridge is an iconic structure known around the world, and I never tire of this view. Yet there are countless more delights to be found across the landscape leading into this narrow, rocky passageway. Craggy cliffs, hidden beaches, and patches of woodland are revealed to those who explore the ecotone where land meets sea. Every stretch of the San Francisco coastline offers breathtaking views, and crowds are often minimal.

If I were asked to choose a mascot to represent this landscape, the brown pelican would have no rivals. To the inexperienced observer this might seem an odd choice. Weighing up to eight pounds, with a wingspan greater than 7 feet and a curving neck that culminates in an improbably long, hooked bill, brown pelicans look like make-believe creatures from a child's storybook: gangly, disproportionate, and comical. Yet airborne pelicans are the epitome of grace—flapping with slow ease; making fast, steep plunges in pursuit of fish; flying in long, curving formations that follow the breaking lines of waves.

In the 1820s and '30s, while traveling across the nation to study and paint avifauna, John James Audubon had many opportunities to observe brown pelicans. He found them to be "one of the most interesting of our American birds," and had this to say about pelicans on the wing.

"The flight of the Brown Pelican, though to appearance heavy, is remarkably well sustained, that bird being able not only to remain many hours at a time on wing, but also to mount to a great height in the air to perform its beautiful evolutions. Their ordinary manner of proceeding, either when single or in flocks, is by easy flappings and sailings alternating at distances of from twenty to thirty yards, when they glide along with great speed. They move in an undulated line, passing at one time high, at another low, over the water or land, for they do not deviate from their course on coming upon a key or a point of land. When the waves run high, you may see them "troughing," as the sailors say, or directing their course along the hollows. While on wing they draw in their head between their shoulders, stretch out their broad webbed feet to their whole extent, and proceed in perfect silence."

Autumn weather is as changeable as a teenager's moods. On Sunday night a heavy bank of clouds rolled in just as the Harvest Moon began to peek over the eastern horizon. The low pressure system parked over our heads and remained in place for two days, bringing two inches of much-needed rain.

Wednesday dawned fresh and golden. By early afternoon warmer air had caused unusual cloud formations to build up. Altoculumulus undulatus clouds are named for their resemblance to rippling wave trains along

the surface of the water. Also known as billows, these clouds form as the result of wind shear. Localized differences in wind speed and direction break up larger altocumulus clouds, reshaping them as narrow cloud-rolls. Billows may be ramrod-straight or form gentle curves, but are always evenly spaced in parallel rows.

I recall seeing billow clouds a few times in my childhood. Back then I found their symmetrical design a little frightening, reminiscent of the ribs of some skeletal sky-giant. As an adult I observe natural phenomena through the rational lens of science. Yet plenty of youthful imagination still tinges my view. Standing in the yard my eye was drawn to the straight line of those clouds, and for a moment I imagined having the ability to fly along that sky-path. But even as I watched, the clouds began to lose their structure—joining then stretching, thinning and breaking apart. Within 20 minutes, the sky was completely clear and blue. And I remained affixed to the ground.

Tentative sunlight at the terminus of the week brought local maple trees to the peak of color. While our neighbors began to spend evening hours raking, trees in our meadow and yard have steadfastly held on to their leaves. A golden glow fills the air at all hours, seeping through the windows and reaching my office as I work. As if I needed another distraction!

But this too shall pass. As I write this in the late hours of Friday night, the drying leaves of a pin oak outside my office window begin to rattle. The wind has picked up from the west. With it, capricious Autumn may bring the first snow of the season.

Announced by all the trumpets of the sky,
Arrives the snow
—Ralph Waldo Emerson, from "The Snowstorm"

I've spent an undue share of my life pondering how to achieve my dreams and find good, meaningful work. Sometimes thinking is the precursor to creative work. But let's be honest. It can also be nothing more than fuel for the ego, an excuse to avoid trying the gifts we possess and doing the work we are meant to do. Ralph Waldo Emerson wrote, “Thought is the blossom; language the bud; action the fruit behind it." I am so moved by this story of a young person whose curiosity and recognition of a need led him to act, despite scarcity of emotional or financial support.

May your dreams continue to bear fruit, William Kamkwamba!

Now in his early 20s, William has written a book about his experiences. To learn more about William’s work or support his efforts, watch the videos below and use the widget to peek inside The Boy Who Harnessed the Wind. Also visit his homepage or his guest blog on Huffington Post.

The desert of east-central Nevada is lovely, cold, and deep. But as the first sunlight tinges thin clouds above, it’s time for William Grote to get moving. Quickly packing his belongings into the back of his Hauler, he hits the road. This three-wheeled bike looks a bit like an overgrown Mars Rover—and it’s got some of the same features. Wide tires enable the Hauler to traverse off-road terrain. And like the Rover, this vehicle carries a solar panel connected to a battery pack, which stores energy for later use. The battery powers an electric motor to assist the rider through challenging conditions, and also provides connections for AC power. (William’s pedal-power also contributes to battery storage.) The Hauler’s frame is designed to carry 500 pounds, in the form of passengers or cargo behind the recumbent driver’s seat.

William’s journey began at Hood River, Oregon, site of the Hauler factory. He left in early September, planning to follow the U.S. Bicycle Route System through the central United States to a final destination at Mount Pelier, Vermont. Total distance: more than 4000 miles—including an elevation change of 12,000 feet between the Rocky Mountains and the Great Plains.

This would be a profound personal journey under any circumstances. But William has added another component that also makes the journey relevant to communities through which he passes. As he travels, Williams will stop at local (usually rural) schools and other community centers. He sees it as a chance to educate about sustainability. In particular, William hopes to share the philosophy of cradle-to-cradle resource use, which looks at the full life-cycle of a product. How can production be more efficient, use  more sustained, and disposal less prevalent? Asking children to consider these questions reminds them to think toward the future. This sharing of ideas is the essence of William's journey, which he calls Read Across America.

On this cold morning William will pedal uphill to a small school in Baker, Nevada. One teacher, four grades, a dozen students. Under the brightening desert sun all the kids, the teacher, and many parents—in fact, pretty much the whole population of Baker, NV—gathers and mounts their bikes. This annual event is called the Wheel-A-Thon. A snaking line of townspeople makes its ways eight miles southeast to the neighboring town of Garrison—which happens to lie just across the border, in Utah. William rides along, one of the gang today, his crazy contraption gathering sunlight that has slipped between billowing, white clouds. Turning around they retrace the route, arriving at the schoolhouse in time for lunch. William reads Dr. Suess’s The Lorax and discussion ensues. Then he’s off again. He’s got promises to keep, and miles to go before he sleeps.

million Americans now pedal along streets and highways,” revealed author John E. Lodge. “And, last year, factories in the United States turned out 750,000 machines.” As today, people rode for fun, exercise, and as a mode of transportation. Lodge reported that the craze had also swept Hollywood. “One prominent actor pedals ten miles between his home and the studio twice a day, rain or shine.” It was during this period that many urban bike trails were established. Bike technology advanced to include multiple-speed gear shifts, safety features, and conveniences such as softer seats and kick stands.

Bikes have never lost their appeal as a source of fun, entertainment, and exercise. But the past century has seen the automobile roll over every competitor as the number one form of transportation. In 1960 there were about 74 million personal passenger vehicles, trucks, buses, and motorcycles in the United States. Today that number has escalated to more than 250 million. To make this comparison meaningful, of course, we must factor in population change. According to the U.S. Census Bureau, U.S. population has increased by about 70 percent since 1960—from 181 million to 307 million. Meanwhile there has been a greater than three-fold increase in the number of vehicles on American roads.

But wait, there’s more! Changes in fuel economy during this half-century have been incrementally slow. Between 1960 and 1990 the average mileage (for all vehicle classes combined) crawled upward from 12.4 to 16.4. Corporate average fuel economy (CAFE) standards determine the mileage for passenger vehicles and light trucks, and they tend to represent the higher end of the mileage spectrum. Even so, the 25-year period beginning in 1980 saw only a 7 percent increase in fuel economy, reaching 24.8 mpg in 2000 and remaining near that level thereafter. New CAFE standards were passed in May 2009. By 2016 passenger vehicles must achieve 42 mpg and light-duty trucks 26 mpg. But poor fuel economy is only part of the problem. Data from the 2007 American Community Survey (a tool used to collect demographics between the 10-year national surveys) reveal that 76 percent of Americans drive alone in their cars to work. I’ll spare you the statistics on the gasoline consumption that results from this behavior. Suffice to say that it’s a lot.

Because you're savvy, I'll bet you can predict the next fact. A single gallon of gasoline emits 19.4 pounds of carbon dioxide into the atmosphere. (The number is slightly higher for diesel.) Burning fossil fuels has been linked to climate change, but also to increasing rates of asthma and other respiratory conditions. Meanwhile, millions of Americans experience heart disease, stroke, diabetes, obesity, and the precursors to these life-threatening conditions. Why? Because we don’t get enough exercise.

The National Institutes of Health have a simple solution. To promote a healthier lifestyle, and to protect our environment, NIH recommends biking and walking. (You knew I’d come full-circle eventually, didn’t you?)

“The European countries with the highest levels of walking and cycling have much lower rates of obesity, diabetes, and hypertension than the United States. The Netherlands, Denmark, and Sweden, for example, have obesity rates only a third of the American rate, while Germany’s rate is only half as high… Walking and cycling also help alleviate traffic congestion, save energy, reduce air and noise pollution, conserve land, and produce various other environmental benefits.”

What would that entail, and what would be the environmental benefits? A study commissioned by the Rails to Trails Conservancy clarifies these questions. It suggests that half of all the outings we take in a car are so close to home that we could bike there in 20 minutes. Twenty-five percent of our errands are significantly closer—accessible on foot in 20 minutes. Rails to Trails determined that “modest increases” in biking and walking by Americans “could lead to an annual reduction of 70 billion miles of automobile travel… equivalent to cutting oil dependence and greenhouse gas emissions from passenger vehicles by 3 percent.” Doesn’t sound like much? Here's a little perspective. The U.S. Senate just worked for months to agree on a complex cap-and-trade scenario that might reduce GHGs by 20 percent (below 2005 levels) between now and 2020. Losing 3 percent by an immediate behavioral change looks pretty good by comparison.

The wobbly economy was a good prompt in that direction for some folks, a process that has been aided (in some places) by infrastructure. The City of New York has constructed approximately 200 miles of bike lanes and plans more. Bike traffic has already increased by 35 percent. And despite its harsh winters Minneapolis is ranked as one of the nation’s most bike-friendly cities (second only to Portland, Oregon), offering more than 120 miles of bike lanes and trails, bike-friendly commuter trains, and more. Even Los Angeles, one of the most sprawling cities in the nation, has invested in a detailed plan to encourage and accommodate biking among its population.
 

As in the 1930s, popularity has bred a host of new biking technologies. Among these is the electric bicycle. Although more expensive than traditional bicycles, e-bikes have a distinct advantage: a built-in motor. You pedal anyway, right? On an e-bike, some of the kinetic energy from that motion is converted to chemical energy and stored in a battery. It’s available when the going gets tough, such as when riding into a headwind or up a hill. So far, China and India represent the biggest markets for e-bikes. Of 23 million e-bikes sold in 2008, fewer than 200,000 were purchased in the U.S. An innovative new alternative is the Hauler. Built more like a recumbent bike, the Hauler’s larger frame offers space to carry passengers or cargo—up to 500 pounds. Its battery is charged by a combination of leg-power and the original source of energy: sunlight. A solar panel is mounted on the slanted “roof,” offering longer battery storage, faster speeds, and more oomph on long and challenging trips. The designers, Lorax Motor Works of Oregon, envision it as an ideal vehicle for any setting: local rides, long-distance trips, or in developing nations where the demand for vehicles is on the rise. And like all e-bikes, the Hauler achieves transportation with no emissions.

Whatever form it takes—from a rusty old Schwinn to the sleekest racer or the most advanced electric model—the bicycle is more than a toy, exercise machine, or vehicle. Albert Einstein claimed to have thought of the theory of relativity while cycling. Suffragist Susan B. Anthony saw the bicycle as a source of independence for women. And author H.G. Wells wrote, “When I see an adult on a bicycle, I do not despair for the future of the human race.” In 2008 U.K. Prime Minister Gordon Brown declared, “The place of cycling in our society is set to grow, and I am committed to doing everything possible to encourage that.” The statistics show that Americans also love biking. But are we willing to put on our helmets and ride as a solution to what plagues us?

"Beauty has as many meanings as man has moods.
    Beauty is the symbol of symbols.
Beauty reveals everything, because it expresses nothing.
When it shows us itself, it shows us the whole fiery-colored world."
    —Oscar Wilde

In the early morning hours I stand at the kitchen window, alone with the silence and my thoughts. The last few stars fade overhead as a pale glow touches the treeline across the lake.

To my surprise, a late-feeding bat appears over the meadow, making a wide sweep at canopy level. The bat passes just a few meters in front of the window. Suddenly it lurches to the side, down, then rapidly forward. Such maneuvers make bat flight appear haphazard

and clumsy, but I know better. Bats are expert fliers, rivaling birds at every turn.

I think about the amazing structure of a bat’s wing. Evolutionarily, this wing and my arm are homologous—they have the same basic skeletal structure, which can be traced back to a common (if very distant) mammalian ancestor. In x-rays this homology would become immediately apparent. The main difference, of course, is that the little flier’s finger bones are proportionately much longer. A bird’s wing has fewer, more robust bones. This sturdy framework provides easy lift, even from the ground—but far less flexibility. Bats can not only bend the elbow but move each digit independently to make rapid changes in flight direction and speed. (What about the thumb, you may wonder? This shorter digit protrudes from the leading edge of each wing, serving as a grappling hook and all-purpose tool.)

When hunting small prey, such as micromoths or mosquitoes, a bat may simply grab the insect in its mouth. Scientists at Wake Forest University have found that large prey, such as tiger moths, are handled differently. The bat zooms up to a large insect and sweeps it up in a wing. Then the insect is dropped into the cupped tail membrane. Finally the bat bends forward and gobbles up the prey, as if eating from a bowl. Keep in mind that all of this happens in milliseconds, while the bat is midair. Scoop—gulp—swoop! The red bat, one of our local species, shaves a step off this routine. It flies under the prey and executes a forward roll, making the capture directly into the tail membrane. So efficient.

As "my" bat flutters into the shadowy woods of our neighbor’s property, I idly hope its aerobatic foraging was successful. Moments later my attention is diverted to the bottom of the hill, where robins have begun to pour from the canopy of a big maple tree. They emerge in groups of two, six, then dozens at a time. Flying low over the meadow, their dark silhouettes cross those of Canada geese on the lake.

Now my meditative silence is officially broken. Robins chuck worriedly as they settle on the lawn for breakfast, and the geese wish each other good morning with a noisy chorus of whistles and honks. Another familiar morning sound comes from within my own home: the contact call of a Blond-Haired Boy.

There’s just a moment more to gaze out the window. Golden light reflects against low clouds and back onto the water. It’s a moment of simple beauty. I can’t pass this to anyone else. But I’ll carry it with me through the day.

fields and wetlands. Streamers of water vapor dance slowly across lake surfaces. Thick white pockets pile up wherever the landscape forms a shallow basin. Now the sun has risen a few degrees above the horizon. Light is scattered through the layers of fog, filling the sky with peach-colored haze. I’m grateful for the lack of traffic so I can safely grab my camera from the back seat and shoot half a dozen frames.

Over the past week or more I have noticed the splotches of color touching maple trees in my neighborhood. Ground fog is the second clue I rely on to confirm that we are shifting from summer to autumn. This time of year the sun sets noticeably earlier and rises later. The days remain warmish, but in the prolonged hours of darkness Earth’s surface cools rapidly by radiation. As heat flows away from the land, air near the surface also begins to cool. When air temperature reaches the dew point, the particles of water vapor within it condense to form droplets of liquid water.

Yet only certain environmental and atmospheric conditions produce ground fog. Aside from radiative cooling, the critical factors are clear and windless skies. On cloudy nights, a larger percentage of outgoing longwave (infrared) radiation is held close to the surface. The air stays warm, so fog can't form. A clear sky allows radiation to escape the atmosphere unimpeded. When breezes whip up, they push water droplets aloft to mix in the atmosphere. On still nights water droplets huddle into mini-clouds that remain close to earth. Ground fog usually evaporates as air warms in the hours after sunrise.

Back on the road, orange light floods my car through the passenger window. On either side of the highway fingers of fog swirl upward, waking at the touch of the sun. A new day has begun. Autumn approaches.

hummingbirds are not as large as crows. That image has remained in my mind. The ruby-throated hummingbird’s bill accounts for one-fifth of its body length. Expand the hummer to crow-size and its bill would be more than 10 centimeters long. The pileated woodpecker provides a useful model. This bird is of comparable size to the American crow, but its bill is elongated like Pinocchio’s nose after he’s told a series of whoppers. Rather than being chisel-shaped like the woodpecker's, however, a hummingbird's bill is rapier-thin and sharp. Our Superhummer would be a Musketeer among birds. Mon dieu!

The dogfights haven’t ended among our remaining hummingbirds, but a sudden decline in population density has reduced the intensity of these interactions. Three days ago I noticed the absence of any males in the yard. Male ruby-throated hummingbirds always leave in August, heading gradually toward the Gulf Coast. Females and juveniles remain somewhat longer, into October if conditions permit. During that time they may share the yard with dark-eyed juncos and pine siskins. These songbirds also travel south after nesting, but because they eat seed (among other reasons) their migration from Canada may end right here in central Minnesota.

I have often wondered whether the same birds somehow return year after year to our yard. Site fidelity is an aspect of migration that is of concern to biologists. But it can be difficult to prove. Banding studies  shed some light on the question for ornithologists. Captured birds are fitted with tiny metal leg bands. Each band is stamped with a unique number, and may also carry a discrete color pattern. Bands allow individual birds to be identified upon sighting or recapture. At Hilton Pond Center in York, South Carolina, biologists banded 3,614 ruby-throated hummingbirds between 1984 and 2007. More than 430 of these birds came back to Hilton Pond the spring after banding. A couple returned several years in a row. Amazing information can be obtained from such simple techniques, but they require funding, staff, and infinite patience.

Audubon wasn’t terribly scientific when he described the ruby-throated hummingbird as a “glittering fragment of the rainbow”—but he was utterly accurate. I watch a little female perch atop our rain gauge between bouts of feeding and chasing. Her belly is rotund with nectar and she looks perfectly fit. This wee gem has a long journey ahead. I don’t know if she’ll make it back to this yard in the spring. But we’ll keep the nectar flowing, just in case.

Follow the hummingbird migration, and that of other species, using maps posted by Journey North. These are updated daily based on data provided by citizens across the continent.

Much as I love spending time outside, it’s no exaggeration to say that I could gaze out the kitchen windows for a whole day. The east window provides a view of the hillside meadow and lake that comprise our “backyard.” We don't live in isolation; I can see houses on the far lakeshore and, at night, lights from the highway beyond. Yet this is something more than the typical sprawling suburban property. It’s just on the edge of wild. We routinely observe loons on the lake and bald eagles overhead. The tame and familiar wildlife—deer, raccoons, and woodchucks—are occasionally joined by minks, coyotes, and huge flocks of turkeys.

The expansive lakeview is always tempting, yet today I’m drawn to the smaller, paired windows over the kitchen sink. There's no grand vista framed here—just the front yard. It’s a yard like many others in our area. There’s a deck and a small, screened cabin where we sometimes take our meals. Several flower patches and bird feeders are scattered across the open space. A big, hundred-year-old boxelder tree throws shade over the grass where my young son plays. A tidy orchard gives fruit of three varieties, and a white picket fence defines part of the property line. This view is appealing not so much for its scale as for its intimacy and the relatively invisibility offered by a reflective window pane. Wildlife—particularly birds—come so close to the windows that it’s breathtaking. At this moment a downy woodpecker clings to a suet feeder half a meter from my face, but the bird is heedless of my presence.

The woodpecker circumambulates the birchbark feeder in search of a good toehold. I lean over the sink to carefully open the opposite window. Moments later a distinctive sound reaches my ears. It’s the low, whirring drone made as a hummingbird’s wings beat the air more than 50 times per second. A male ruby-throated hummingbird rockets in from the east side of the house. It clears the suet feeder—and my corner window—by a narrow margin of safety. The emerald green bird’s destination is the nectar feeder that hangs from a pole in the deckside flower garden. It hovers before the feeder, dipping down to feed then popping back nervously to look around. Suddenly the hummingbird pivots toward me. The feathers of its gorget (throat)—which had at first appeared black—now flame metallic red. This burst of iridescence occurs when sunlight reflects off microscopic air bubbles located inside each barb of the gorget feathers. (If you’ve never examined a feather closely, there is a long, stiff central shaft with many thin “branches” extending off the sides. These branches are the barbs.) Iridescence is only visible when the bird and observer are face-to-face. The flash of color fades when either party changes angle relative to the sun. And it doesn’t take long for this to happen. The hummingbird holds its position barely long enough for me to complete a full breath cycle. It emits a rapid series of high-pitched chitters that seem out of proportion to its size then lunges forward in a wide, arcing sweep over the deck. I suspect the source of the bird’s annoyance, but it takes a moment for me to locate it. Another male hummer has flown near the feeder.

Minnesota lies too far north to support hummingbirds year-round. Their presence is limited to the warmer months, when flowers are blooming and nectar supplies are ample. Even when food is readily available hummingbirds must conserve energy by entering a hibernation-like state called torpor for part of every day. A generalist feeding strategy also aids their survival. Rather than focusing on a narrow category of foods, they feed opportunistically on a variety of items. All hummers are known for their love of nectar, but ruby-throated hummingbirds are especially open-minded tipplers. Due to loss of habitat throughout their range, human-made nectar feeders are a crucial source of food. Where they can get it, however, these birds take nectar from any reddish, bell-shaped flowers large enough to accept their beaks. That includes everything from phlox and Monarda (aka beebalm and wild bergamot) to morning-glory and honeysuckle. In our yard, ruby-throated hummingbirds also go for giant hyssop. The pale lavender flowers of this mint species are tiny, but they form tall inflorescences atop stems that tower over my head. Ruby-throated hummingbirds are known to follow sapsuckers in spring. The sapsuckers drill small, round wells in the bark of maple trees to release sap, and hummingbirds take advantage of the free resource. Throughout the year they also seek small insects and spiders, capturing prey mid-flight or scooping it off surfaces.

Hummingbirds spend at most four months in Minnesota. They show up during the second or third week of May, depending on weather conditions here and along their migratory path from the south. I always try to have the nectar feeders out and waiting, for they arrive as thin as wraiths. It seems that a creature so slight must be tossed by the wind like cottonwood fluff. Hummingbirds appear to have turned this liability to an advantage in some circumstances. When possible they wait to fly with favorable tail winds, allowing the gusts to provide a push in the right direction during migration.

Their imperative here in the northlands is clear: establish a territory, build a nest, and raise a healthy brood of Lilliputian offspring. By early August the breeding season has ended and the birds begin to respond to different internal rhythms. Migrants from breeding populations in Canada and northern Minnesota now join our resident hummers. If mid-August seems a bit premature for migration, consider that by mid-October these wee creatures must cross the Gulf of Mexico to reach their winter ranges in the Yucatán Peninsula and Central America. The birds seem to focus on one goal in preparation for this long journey: getting fat. During the breeding season male ruby-throated hummingbirds have an average mass of 2.5 grams. Balance an American penny on the tip of your finger to get a sense of how insubstantial that mass is. Females can be up to 2 grams heavier—closer to the mass of a nickel. In less the two weeks, through a vigorous program of nectar sipping, a hummer may increase its body weight by 75 percent. No body builder ever took weight gain more seriously. At this time the birds engage in fast and furious territorial battles over access to feeders and flower patches. Females are as just as contentious as males. The bird I’m watching now probably nested in our yard, and is not eager to share resources at such a crucial time. I crane my neck to watch as he chases the interloper away, but the two miniscule green birds are immediately lost among the foliage.

Distracted by the hummingbird drama, I’m startled when the teakettle begins to sing. I pour the water and leave the cups to steep for the requisite three minutes. Delivery of my partner’s steaming tea is the last part of this afternoon ritual. It’s sometimes an excuse for conversation, but more often a simple gesture, a quick and quiet interlude in the midst of our mutual workdays. When I get back to the kitchen my herbal tea will require only a spoonful of honey to make it ready. Allowing myself a last glance out the window, I see that a mean, green flying machine is back at the nectar feeder. Whichever of the two male hummingbirds has prevailed, it wastes no time in savoring the sweetness of its prize. As I return to my quiet work habitat, that sweetness lingers in my mouth as well.