The two small sandpipers sashayed towards me on our beach on Lake Superior’s south shore. It was August 3. Shorebirds were already migrating—and here some were, just as my summer vacation was beginning.
Shorebirds are notoriously difficult to identify—They are remarkably similar in plumage. They might be seen in breeding plumage, or others in winter plumage, or some half-way into the molt. Although they might be described as differently-sized, a viewer can’t discern a 5” bird from a 6” bird at, say, 25 feet. I often resort to behavior to try to ID these birds, and frequently I throw up my hands and throw in the towel. But Least Sandpipers are different.
These birds walking my way had two characteristics which nailed an ID: first, they were extremely small, dainty, and delicate. This eliminated the more robust species, like willets and yellowlegs. But Least Sandpipers, Western Sandpipers, and Semi-Palmated Sandpipers are within an inch in length of each other. What sets Leasts apart is their yellow legs. Although field guides warn that the yellow legs can appear dark if covered with mud, or in poor light, I saw their legs were unmistakably yellow.
I froze and the birds came closer. Soon they were five feet from me. I could see every detail without binocs. They seemed tame. I wondered if they were exhausted—they appeared reluctant to fly.
Least Sandpipers visit Minnesota on migration. They are abundant and often flock with the like-sized sandpipers. Their breeding grounds are in the high Arctic . They overwinter thousands of miles away in southern North America and the northern half of South America. Throughout the year, they are seen on mudflats, protected beaches, and inland bodies of water. The eastern birds are known to migrate non-stop, flying from the St. Lawrence Gulf and New England over the Gulf of Mexico in one go.
In the tundra and boreal forest, they nest on the ground on coastal wetlands, bogs and sedge meadows. It’s simple: the male scraps out a depression on the substrate. The female adds a sparse lining of dead vegetation. Least sandpipers do have an aerial courtship display, with the males spiraling upward, then doing a diving descent to earth.
Both sexes share incubation. The female has an evening sit; the male incubates the rest of the day. When the eggs hatch and little sandpipers scurry about, the female takes off—her job is done. The male remains with the chicks until they are ready to migrate.
Ground nesters are vulnerable to a wide variety of predators, including ravens, crows, sandhill cranes and gulls.
Today, Least Sandpipers are widespread and numerous. Researchers estimate the population at 700,000 birds. But even though they are the size of a sparrow, market hunters went after them and decimated them at the turn of the last century. The 1918 Migratory Bird Treaty Act stopped the slaughter and the population rebounded.
Today, one major concern is the loss of wetlands, by destruction or degradation. While the western and central populations are stable, the eastern population has been declining by as much as 15.8% in the Canadian Maritimes.
I watched the two sandpipers for nearly half an hour, never needing my field glasses. They skittered ahead if a human walked near. Then finally, the human encounter was too close and off they flew to a less traveled beach. The next day they were once more flying south.
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