Yours truly gets memorized by swifts hunting for insects in a meadow, endlessly flying in ways that seem to defy physics as we know it. Wonderful, never-ending, the common swift does something, save for raising chicks, no other bird does ... it stays in the air without landing, for years.
I found a dead common swift once, a husk of a bird under a bridge over the River Thames, where sunlight from the water cast bright scribbles on the arches above. I picked it up, held it in my palm, saw the dust in its feathers, its wings crossed like dull blades, its eyes tightly closed, and realized that I didn’t know what to do. This was a surprise. Encouraged by books, I’d always been the type of Gothic amateur naturalist who preserved interesting bits of the dead. I cleaned and polished fox skulls; disarticulated, dried and kept the wings of roadkill birds. But I knew, looking at the swift, that I could not do anything like that to it. The bird was suffused with a kind of seriousness very akin to holiness. I didn’t want to leave it there, so I took it home, swaddled it in a towel and tucked it in the freezer. It was in early May the next year, as soon as I saw the first returning swifts flowing down from the clouds, that I knew what I had to do. I went to the freezer, took out the swift and buried it in the garden one hand’s-width deep in earth newly warmed by the sun.
And they are doing more. As Dokter and his colleagues write, migratory birds orient themselves through a complex of interacting compass mechanisms. During vesper flights, swifts have access to them all. At this panoptic height, they can see the scattered patterns of the stars overhead, and at the same time they can calibrate their magnetic compasses, getting their bearings according to the light-polarization patterns that are strongest and clearest in twilit skies. Stars, wind, polarized light, magnetic cues, the distant stacks of clouds a hundred miles out, clear cold air, and below them the hush of a world tilting toward sleep or waking toward dawn. What they are doing is flying so high that they can work out exactly where they are, to know what they should do next. They’re quietly, perfectly, orienting themselves.
Read Helen Macdonald's extraordinary article in its entirety. Worthwhile to the max.