When raptors stream across the sky by the dozens, hundreds, or thousands, your ground-level ID clues, such as coloration or field marks, become illegible. Instead, you have to rely on body-shape silhouettes and flight patterns to distinguish between species. The best way to learn these cues is by going to a hawkwatch, says Melissa Roach, program director at NJ Audubon's Cape May Bird Observatory in New Jersey. “Most of the year raptors are spread out, they’re hard to find, they’re in low numbers and low densities—so you don’t get the repetition you need to learn any new skill.” Not only do you get raptor volume at a hawkwatch, but you can also sit near experts, like Roach, who will walk you through the identification process. She gets you started here with a few widespread U.S. species.
“This is your baseline buteo,” Roach says. “Learn it in and out, then base other species off of it.” Red-tailed Hawks are among the biggest raptors, but size varies: A large female can weigh twice as much as a small male. Their rounded wings appear muscular. “It looks like they have biceps,” she says. “It’s not a skinny or slim wing—it’s thick and bulging.” Red-tailed Hawks are experts at soaring and, when riding a strong updraft, can glide effortlessly for minutes at a time. The heavy buteos appear to confidently master the air, taking wide, slow turns and powerfully flapping only when it is absolutely necessary.
Sharp-shinned vs. Cooper’s Hawk
“This is one of the hardest IDs, so don’t feel intimidated when you don’t get it right away,” Roach says. Sharpies and Cooper’s are agile accipiters with short, rounded wings and long tails. Sharpies are energetic and flap often, while the sturdier Cooper’s prefer to soar, executing forceful, deliberate flaps. “The main thing to look at is the head projection,” she advises. A Sharp-shinned Hawk’s small head sits within a valley between its wings, created when it juts its wrists forward. A Cooper’s Hawk’s relatively larger head projects in front of the wings’ leading edge.
American Kestrel, Merlin, Peregrine Falcon
Falcon migration typically follows coastlines. American Kestrels, the most diminutive U.S. falcons, are rather dainty, playfully wandering in flight and flapping more than their cousins. “They’re the happy-go-lucky falcon,” Roach says. “They look like they’re having a great time.” Merlins are superficially similar to kestrels, but in the air they have an entirely different attitude. “Merlins fly with a purpose,” she says. They don’t wander. “Before you can say, ‘It’s a falcon,’ it’s gone.” Peregrine Falcons are larger than the other two, with a broad chest and extra-long wings and tail. “They’re bigger and more powerful overall,” she says. They cross the sky like a jet, often surpassing other raptors in the stream.