"Who-ha-hoo-o-o is Ready for Spring?"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. ![]() Owl wingprints in the snow, January 2010 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. ![]() Curious about the birds that live in your backyard? You can learn more--and contribute to scientists' understanding of winter bird populations in the United States--by participating in the Great Backyard Bird Count, which takes place every February. A Gallery of Winter BirdsI AND THE BIRD #114 "Soaring Survivors: Pelican-Watching in San Francisco" ![]() Fog begins to lift above the Golden Gate Bridge 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. ![]() Brown pelican on Santa Barbara Pier. (Photo courtesy of Leigh Hill) 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." ![]() Brown pelicans fly in formation as the sun peeks through dense fog, San Francisco Audubon was not alone in his appreciation of pelicans. Women of the nineteenth and early 20th centuries considered it the height of fashion to festoon their hats with feathers. Pelicans, among many other bird species, were hunted by the thousands to fulfill orders for the millinery trade. Pelicans were vulnerable to other threats, as well, including egg collection and hunting by fishermen who considered pelicans to be their competitors for fish. Passage of the Migratory Bird Treaty Act in 1918 curtailed these forms of collection. Yet surveys in the 1960s showed that brown pelicans had all but disappeared from California. Only a small nesting population remained on one of the Channel Islands, off the coast near Ventura. The birds' killer this time was almost invisible—carried on the wind and in water, hidden in the tissues of fish which the pelicans consumed. It was dichlorodiphenyl-trichloroethane—better known as DDT. First synthesized in 1873, DDT was virtually forgotten until the 1930s when Swiss chemist Paul Müller discovered its effectiveness as an insecticide. In World War II DDT was applied to protect Allied troops from diseases spread by mosquitoes and lice. Dr. Müller won the Nobel Prize in Chemistry for his work, which was seen as a life-saving advancement in the fight against insect-borne diseases. After the war, and through the 1960s, DDT was widely used in agriculture and advertised as a safe treatment for household pests. Human health risks from the chemical were not immediately apparent, but evidence of environmental hazards soon began to mount. DDT has a long life in the environment, as do the products of its chemical breakdown, DDE and DDD. These chlorinated hydrocarbon chemicals move up the food chain from microscopic organisms to fish and thus to pelicans and other piscivorous birds. They accumulate in fatty tissues over time, so that larger and longer-lived animals—such as pelicans—accumulate proportionately greater chemical loads than smaller, shorter-lived species. Humans are also affected by this process, called biomagnification. Biologist Rachel Carson reported the effects of DDT in her ground-breaking book, Silent Spring, published in 1962. She wrote about the sudden decline among populations of American robins and other ground-feeding birds after DDT was used to treat Dutch elm disease in many communities during the 1950s. Direct exposure to the insecticide caused many of these small birds to die immediately. But Carson was also concerned about long-term effects. She noted that for many years DDT had been sprayed along the Atlantic coast to combat marsh mosquitoes, and knew the effects on marine species, and reported the situation in Silent Spring: "Fishes and crabs were killed in enormous numbers. Laboratory analyses of their tissues revealed high concentrations of DDT—as much as 46 parts per million." Carson knew that fish make up a significant part of the bald eagle's diet, and extrapolated that by virtue of their long lifespan eagles and other fish-eating birds would store proportionately larger concentrations of DDT than small, shorter-lived marine animals. As a consequence, she wrote, "they are less and less able to produce young and to preserve the continuity of their race. (Carson 122)" Declines in the rate of bald eagle reproduction had already been observed. Carson felt certain DDT was to blame, though she could not explain how the chemical caused physiological damage. Research in the late 1960s revealed the mechanism by which DDT affects bird reproduction. Calcium carbonate is the primary mineral component of eggshells, and serves as a crucial source of calcium for embryonic skeletal development. Calcium carbonate is secreted by the bird's shell glands during egg formation. It is apparently blocked by the presence of DDE, a chemical that results from the metabolic breakdown of DDT. By the late 1960s, brown pelicans nationwide produced eggshells that were, on average, 20 percent thinner than in years prior to DDT use. Some populations of California brown pelicans were found to have shells only half as thick as normal. Brown pelicans build a stick nest on the ground or in a tree. The male and female of each pair take turns on nest duty, sitting on the edge of the platform and incubating the eggs beneath large, webbed feet. DDE-thinned eggs were delicate and susceptible to cracking under pressure, making pelican reproduction an abysmal failure. Brown pelicans might have gone the way of their ancient dinosaurian kin. But thanks to a 1972 ban on DDT and protections under the U.S. Endangered Species Act, extinction of the species was averted. The intervening decades have seen a slow but sustainable recovery of brown pelican populations, significant enough to lead the U.S. Fish and Wildlife Service in 2008 to propose delisting of all brown pelican populations from the Endangered Species list. That process was finalized on 17 November 2009. On your next visit to San Francisco, tear your eyes from that big, beautiful bridge for just a few minutes. Watch instead the narrow valleys between cresting whitecaps, and look to the sky at hilltop level. Better yet, wend your way westward and south through city neighborhoods to China Beach, Lands End, or Fort Funston. It won't be long before an undulating line of pelicans drifts in, skimming silently across the water or plunging-and-plundering in search of fish. Don't be embarrassed if your heart starts to beat a little faster. It's appropriate to be thrilled when you witness a miracle. ![]() Fog begins to clear along the Golden Gate, revealing the full bridge and the hills of the Marin Headlands beyond "Passing Thoughts” ![]() "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 "On the Wing" For weeks the yard has hummed (yes, that's a pun) with ruby-throated hummingbirds. Throughout the day males, females, and juveniles zipped between feeders, flowers, perches, and hideouts. The chase was always on, and tiny birds whizzed past us, in pursuit or retreat, whenever we ventured into the yard. Actual fights between hummingbirds are apparently uncommon, though they seem to expend endless energy keeping each other from nectar sources. In Birds of America, John James Audubon described this habit. “They are quarrelsome,” he wrote, “and have frequent battles in the air, especially the male birds. Should one be feeding on a flower, and another approach it, they are both immediately seen to rise in the air, twittering and twirling in a spiral manner until out of sight.” A few years back I read an article about hummingbirds in Smithsonian magazine. The author commented how fortunate it is that "Afternoon Delight" Rain or shine, subzero or sweltering, around 2:00 p.m. each weekday some internal alarm prompts me from my chair toward the kitchen. Although this is a short migration, it involves a radical shift in habitat. My office is tucked on the north side of the house and flanked by an Entish pin oak tree. Those with an aversion to low light might find the room too solemn, but I enjoy its cool, shady attitude. It feels as though I have my own little bower among the branches of the house. I work here for hours at a stretch, cocooned in a silence that is conducive to concentration but not oppressive. There’s a palpable shift in my awareness when I enter the kitchen, which is flooded with light throughout the day and in all seasons. Wide windows on its east and west walls, and exposure from the south through an adjoining mudroom, make the kitchen open and lively. This is the real heart of our home. Even a quick infusion of its light, color, and space gives me just the dose of energy I need to remain focused through the afternoon. A cup of tea doesn’t hurt, either. Teatime is not a fancy affair. I don’t prepare food, and never even sit down. But there is a ritual associated with this break. I take down two mugs from the cabinet. One is chosen randomly, though it can’t be too large. The other is my favorite mug, made of thick, cream-colored ceramic with a handle that looks like a twisted twig. Across its surface are painted two of the birds that commonly appear in our yard: the Baltimore oriole and the blue jay. The style of painting looks somehow old-fashioned, like it belongs in a dusty field guide you might find tucked away in your grandparents’ library. I choose a bag of good black tea to go in the first mug. Something fruity or spicy goes in mine—but no caffeine allowed. Finally I fill the burnished metal teakettle and place it on the burner. Now begins my favorite part of the routine. Until the kettle sings I have a few free moments, with nothing more important to do than watch. |