The Incredible Journey of a Migratory Shorebird

Birds are in trouble. Migratory shorebirds are in especially bad trouble. And long-distance migratory shorebirds, like the Hudsonian godwit, may be in the most trouble. “Birds are sentinels,” Stanley Senner told me. “The ecosystems they rely on are ecosystems we rely on as well, though it can take time to convince people of that.” Studies show that, without shorebirds, coastlines erode more quickly, trap less carbon, and are more likely to become unbalanced. In the Yellow Sea, for example, shorebirds feed on crabs whose population needs to be kept in check, as they graze on native vegetation. In some ways, shorebirds are analogous to the wolves that hunt the deer and elk populations that eat the tree saplings that become the trees that beavers use to build dams that help the fish—and so on. Shorebirds also transport and disperse essential seeds and nutrients. Our interests align, as they say. Also, like all birds, they are lovable, alien, awesome, and alive. Not long ago, I saw a dead magpie on a country highway. Other magpies gathered around it, as if saddened and confused. When a car approached, they scattered. After the car passed, they returned to their fallen friend. So there’s also that.

To protect birds effectively, we need to understand them. So much about godwits remains unknown, including where and when they encounter their most mortal threats. Since their epic migration is maybe their most difficult-to-fathom characteristic, we may as well start there.

“We shouldn’t have waited so long to have a baby.”

Cartoon by Jon Adams

The story of bird migration, as narrated in Western civilization, often begins with Aristotle, who wrote that, in the winter, redstarts turn into robins and garden warblers turn into blackcaps. This sounds silly but, compared with the idea that a caterpillar becomes a butterfly, it seems reasonable. Olaus Magnus, a sixteenth-century Swedish priest, argued that barn swallows disappear in the fall because they hibernate at the bottom of ponds. That also seems absurd until you learn about the common poorwill, which resembles an old piece of bark and spends months of winter nestled almost imperceptibly in the crevices of logs or among piles of rocks. This wasn’t scientifically documented until 1948, although the poorwill has long been known to the Hopi as hölchoko, “the sleeping one.”

The Maori tell a story about how a godwit showed their ancestors the way from their ancient homeland of Hawaiki to New Zealand, more than a thousand miles away. But, to most people, avian migrations of that length were long unimaginable. In 1822, a hunter near the German town of Klütz shot down a stork; when he collected the bird, he saw that it had a wooden spear through its neck, later determined to be of African origin. Hunters eventually found more such Pfeilstorchs (arrow storks), giving credence to the hypothesis that the white stork not only migrated but did so between Europe and Africa. In some ways, this was a downgrade: the seventeenth-century minister Charles Morton, who wrote a popular physics textbook, claimed that birds migrated to the moon. He supposed that they fuelled a sixty-day flight there with body fat (reasonable) and that the journey was made easier by the minimal atmospheric resistance in space (also reasonable).

Migratory birds in captivity develop Zugunruhe, an agitated fitfulness, at certain times of year. Scientists don’t know precisely what provoked A34 to set off northward one spring afternoon, with a flock of her fellows, though, if they did, they might better know how her species will be affected by the shifting seasons of our changing climate. Godwits cannot soar like hawks or glide like albatrosses. They migrate by continuously flapping their wings. They must navigate crosswinds and headwinds, storms and maybe an occasional hurricane, continuing on day after day, night after night. As best as we can tell, they do not, while flying, eat or drink or sleep (at least not with more than one hemisphere of their brain at a time). After a journey of hundreds of hours and thousands of miles, they descend on a snow-covered shore at the Cook Inlet of southern Alaska or another favored breeding ground. They land considerably lighter than when they took off. “Many arriving shorebirds seem to be tired,” the ornithologist and conservationist Joseph Archibald Hagar wrote, in his foundational monograph, “Nesting of the Hudsonian Godwit at Churchill, Manitoba,” from 1966. In a field-diary entry, Hagar describes a group of birds that “within a minute or two dropped into some sunny spot out of the wind, tucked heads into scapulars, and went to sleep, not to move again for as long as we watched.”