“The Red-heads (by which name this species is usually designated) may be considered as residents of the United States, inasmuch as many of them remain in the Southern Districts during the whole winter, and breed there in summer. The greater number, however, pass to countries farther south. Their migration takes place under night, is commenced in the middle of September, and continues for a month or six weeks. They then fly very high above the trees, far apart, like a disbanded army, propelling themselves by reiterated flaps of the wings, at the end of each successive curve they describe in their flight. The note which they emit at this time is different from the usual one, sharp and easily heard from the ground, although birds may be out of sight. This note is continued, as if it were necessary for keeping the straggling party in good humour. At dawn of day, the whole alight on the tops of dead trees about the plantations, and remain in search of food until the approach of sunset, when they again, one after another, mount the air, and continue their journey.”
To see and hear the likes today would require being in places like the Weston Bend State Park in Platte County, Missouri, where Mark Robbins counted 684 Red-headed woodpeckers on September 10, 2016 (see eBird Checklist S31525739).