for National Geographic News
On a brisk, sunny afternoon in mid to late September, you can gaze with binoculars into billowy clouds and count thousands of broad-winged hawks migrating south. These crow-size raptors with banded tails soar on currents of sun-heated air in groups known as kettles. A single kettle may contain 200 or more broad-wings, who circle as if a great wand had stirred the sky and caught them in a vortex.
Fall has its subtler migration spectacles. Although blue jays occur year-round in the eastern United States and in parts of southern Canada, they are migratory. In late September, they withdraw from the northern edge of their breeding range and pass through the trees in small bands, a mode of travel that belies their numbers.
Northern flickers are equally common, especially along the coast, where they stream by in loose flocks. Unlike most woodpeckers, flickers spend a lot of time on the ground probing for ants. In flight, they show a white rump. There are two forms: eastern flickers have yellow undersides on the wings and tail, visible when they fly; in western flickers, these parts have a strong reddish tinge.
American kestrels, smallest of North America's falcons, migrate at about the same time as the jays and flickers. As they follow the coast, kestrels often hover above marshes and grasslands, waiting to pounce on rodents, small birds, and insects.
In fall they can be numerous—I have seen 50 in an hour—but on one late September day, I saw only three kestrels the entire morning. A blue jay decided to provoke one of them, a male resting on the tip of a sapling beside a salt marsh. It was a showdown between two of our handsomest birds—the ornate blue jay, a loud smart aleck, and the dapper American kestrel, a graceful speed demon.
Although slightly larger than a male kestrel, the blue jay has inferior weaponry. Sounding its raspy alarm call, the jay flew at the kestrel, who shrugged off the assault. When the jay persisted, the kestrel retaliated with talons bared.
The kestrel drove off the jay, but then a crow flew in and drove off the kestrel. The crow intervened not to protect its fellow corvid—blue jays strongly dislike crows, and the feeling, I am sure, is mutual—but solely because a crow cannot resist the temptation to bully a small raptor. If the kestrel's larger cousin, a peregrine falcon, had come by and launched an attack, the crow would have been lucky to escape with its life.
After witnessing the brawl, I walked on the beach and saw hundreds of tree swallows flying west along the edge of Long Island Sound, a migration no less impressive than that of broad-winged hawks. If I had stayed awhile, I probably would have counted a thousand swallows, but I could not resist foraging into a rank growth of shrubs and weeds above the beach.
The plants were going to seed and had attracted a small convention of sparrows: savannah, song, swamp, white-throated, and chipping sparrows. American goldfinches in their dull yellow non-breeding plumage outnumbered any single species of sparrow, and as I waded through the fading foliage, the goldfinches were always the first birds to flush.
Keeping just ahead of me, the goldfinches moved in undulating flight, calling as they took off. Among them I found a female indigo bunting—a cinnamon-brown bird (the name describes the breeding male only)—and a dozen bobolinks.
In breeding plumage, male bobolinks are mostly black, with a buff nape, white shoulder patches, and a white rump. By early fall they resemble females, having acquired buff underparts and black streaks on their sides and back. The boldly streaked, decidedly yellow underparts of these bobolinks suggested to me that they were immatures.
Ospreys on their southward journeys flew in widely spaced single file above the marsh, some flapping deeply, others soaring gull-like, with wings bowed. In the muddy channels, the numbers of summering great and snowy egrets had waned; most of those remaining were greats.
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