In November, when a cold front comes through southeastern and southcentral Pennsylvania with its roaring, cold, northwest or north winds after a few days of sullen, rainy weather, many hawks and eagles of several kinds migrate through this area, mostly along the southwest running Appalachian Mountains. Sharp-shinned hawks, northern harriers, merlins and red-shouldered hawks are some of those hawk species, in limited numbers. But red-tailed hawks, bald eagles and golden eagles steal the raptor migration show during those wild days in November; red-tails because of their big numbers and eagles because they are eagles. Those last three kinds of majestic raptors cause moments of excitement, inspiration and beauty.
Of course, all these hawks and eagles are migrating south from farther north. And they do so each fall, not to escape winter's cold, but to find reliable food supplies farther south to sustain themselves through that harshest of seasons.
The strong northwest winds are pushed up the southwest running Appalachians by wind from behind. Dead, deciduous leaves, corn leaves from the valleys below and other debris are briskly pushed up the slopes by the wind as well. And hawks and eagles are held aloft along the length of the mountains, particularly the Kittitinny Ridge, by those same winds. Those soaring raptors are pushed up by the wind, but gravity wants to pull them down. With a steadying balance of wings and tails, hawks and eagles forge ahead for hours and many miles with scarcely a wing beat, which saves them a lot of energy.
There are several rocky lookout spots, open to the public, on the Kittitinny Ridge, including Bake Oven Knob, Hawk Mountain Sanctuary and Waggoner's Gap, where these migrating raptors can be easily seen. But many migrating hawks and eagles follow other southwest running ridges in autumn as well.
Sometimes the winds are from the south or east, or don't exist at all. Then raptors scatter off the Appalachians and search for thermals that will carry them up and south. Thermals are sun-heated air that rises. Hawks and eagles get into them and soar upward, circling higher and higher. Then they peel out of the thermal and drift south or southwest for many miles. But because of gravity, those raptors are obliged to seek thermals time after time to give them lift with little effort.
The adaptable, abundant red-tails migrate over Pennsylvania in large numbers, mostly from the end of October, through November and into early December. These large hawks sometimes soar one close after another along the Kittitinny during blustery, northwest winds. But they are also spotted migrating in small groups or lines over farmland in southeastern Pennsylvania, creating feelings of excitement and inspiration among those people who notice them there. Some of those migrant red-tails winter in southeastern Pennsylvania, where they mingle with residents of their kind.
The stately bald eagles migrate through here singly from August into December. This type of eagle can be spotted most anywhere during its autumn migration, around rivers and impoundments where they catch fish, and over farmland where they scavenge dead animals. I've even seen a few soaring over the town of New Holland in the last couple of years. Fully adult balds have the white heads and tails we are familiar with. But first year bald eagles are mostly dark brown with blotches of white here and there. Many balds, both young and older, spend winters in the Mid-Atlantic States. But, I suppose, the magnificent golden eagles are the most exciting of raptors to migrate through southeastern Pennsylvania, from late October into December, with a peak of migration during November. Goldens that pass over this area nested in Maine and eastern Canada. And most of them winter in wooded valleys between wooded mountains in West Virginia. There they kill and ingest rabbits, foxes and other kinds of mammals, and birds, and scavenge dead animals, including white-tailed deer.
Fall hawk migrations extend from August through December, but each species has its own pattern of migration. The majestic red-tails, bald eagles and golden eagles are those raptors that are most prevalent and exciting during November into December. Lucky are the people who see some of these migrant raptors, including in southeastern and south-central Pennsylvania.
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