Every fall when the hillsides begin to glow with the reds, yellows and oranges, there is a crisp, clean coolness that greets you as you step out the door in the morning.

In our case, we always feel a draw that pulls us to a mountain vista or coastal headland. What’s the special attraction? It’s the streams of thousands of hawks — falcons, accipiters, and buteos — moving south.

Unlike most other birds that migrate completely or largely by night, hawks more or less only migrate during the day. We say “more-or-less” because bird researchers stationed on the Empire State Building in Manhattan to study night migration have seen some birds like peregrine falcons and ospreys migrating at night.

But these seem to be the exception; most hawks take advantage of strong winds and thermals to get them more quickly to where they want to be. In the fall in our area, hawks are generally seen in larger numbers when there are winds blowing from the north, especially the northwest.

Falcons such as merlins, American kestrels, and peregrine falcons, and accipiters including Cooper’s hawks and sharp-shinned hawks follow mountain ridge lines.

Along the coast, they can sometimes be seen moving down peninsulas and then following the coastline, passing over islands and the tips of peninsulas as they make their way southwards. Buteos, like red-tailed hawks and broad-winged hawks, are less likely to follow pathways along the coast but prefer inland areas where they are experts at finding places where there are updrafts along ridges and pockets of warm rising air called “thermals.”

These species have long, broad wings that allow them to soar like a hang glider, with little energy expenditure. They can find a thermal and ride the rising column of air like an elevator until, reaching the “top floor,” they glide away and downward at a gentle angle toward the bottom of the next thermal. This allows them to cover vast distances without using up the kind of energy that would be required for them to beat their wings the same distance.

And many hawks do cover vast distances. Broad-wings (which, incidentally, are really the only hawk species in our area that migrates in flocks) make their way all the way to South America. Peregrine falcons, ospreys, and merlins (or at least some of them) are also found in winter in northern South America, Central America, and the Caribbean.

Some of the hawks that migrate to South America have an interesting route that has only recently been elucidated through the use of satellite tracking devices on individual birds. These birds drop south through the Florida Keys to Cuba then move eastward, passing from Cuba to Hispaniola. Here they make their way south to the southernmost point of land on Hispaniola, an area that is now encompassed within the Dominican Republic’s Jaragua National Park. It is more than 350 miles straight south to South America over an area of ocean with no islands — no places to stop and rest or find food or water.

Other hawk species move south but stay in the U.S. for the winter. In recent years, species like merlins, peregrine falcons, and Cooper’s hawks have been wintering in larger numbers as far north as Maine, where they join historically winter resident raptors like bald eagles, goshawks, and sharp-shinned hawks.

There’s no better time or reason to learn your “hawks in flight” — have fun!