Semipalmated sandpipers at Hopewell Cape.

They were not why we stopped that day when driving up the Fundy, coast: instead it was the Flowerpot Rocks we'd read about and thought we'd see rose-colored arches, smoothed by tides, spectacular in rock-like ways, but were they worth the twenty dollars we paid to catch a crowded glimpse, we asked ourselves as we walked on (for having paid, how could we leave and surely there was something more)? There was, we saw, a narrow walk, a tongue of wood above the Bay where people huddled, hushed and still staring, though at what, we wondered, when easing back they let us through, pointing to what seemed to be a nut-brown strip of speckled sand, shrinking as the fide swept in. But how to recreate that day, that breathless moment when I saw, instead of sand, a living mass, close-clustered, chirping, not quite touching? "Ten thousand birds," the young guide said, "that each year fly here from the Arctic to rest for six weeks, eating shrimp, gaining back the weight they lost before they fly non-stop again, three days and four nights to the Tropics." Those were the facts. I needed them, but what I felt can't be described as, suddenly, the birds rose up into the blue cathedral sky, a sheet of liquid waves shook silver, shimmering as wing tips turned like poplar leaves in summer sun, now and now and now again, ten thousand birds that moved as one.

Sarah Rossiter, author of The Human Season, a novel, and Beyond This Bitter Air, a collection of short stories, is a spiritual director and lives in Weston, Massachusetts.