Let’s review. We’ll be seeing a wave of hawks migrating through Maine over the next several weeks, begging to be identified. I’m planning to spend some time up on the Cadillac Mountain Hawk Watch in Acadia, and my hawk-identification skills are a tad rusty.
I need the review as much as anybody.
Hawk identification is complex. Or maybe not. The big raptors tend to identify themselves. Eagles hold their wings straight out like a board, circling slow and steady. Turkey vultures hold their wings in a deep V, teetering constantly. Ospreys have downward-bent wings, crooked at the elbow. Due to these wing differences, all are easy to recognize through binoculars from miles away.
The smaller raptors are harder. Or maybe not. Most hawks passing the summit will be just three species: American kestrel, sharp-shinned hawk and broad-winged hawk. Practice on these three, and the rest get easier.
The American kestrel is only about the size of a blue jay. It’s the smallest falcon in Maine, and a lot of them pass Cadillac through mid-September. They can prey on small birds and rodents, but grasshoppers and dragonflies are more likely to be on the menu. Kestrels must be nimble enough to catch them in midair, so they are able to quickly twist and turn while flying. They have pointed wings and short tails. This gives them a fluttery flight style, apparent even at a distance.
Sharp-shinned hawks are a bit larger than blue jays, which is unfortunate for blue jays because birds make up 90 percent of this hawk’s diet. They rely on surprise attack, with short wings for acceleration and a long tail for maneuverability. Due to this configuration, sharp-shinned hawks fly with a distinctive flap-flap-glide style that is different then the fluttery kestrel.
Broad-winged hawks have — wait for it — broad wings. They’re noticeably larger than the other two, but still smaller than crows. They have a perch and pounce ground-hunting style, eating mostly small mammals and amphibians. As a result, they tend to fly on a straighter path and glide more.
That’s it. On a good day, dozens of these three species will pass the summit of a hawk watch. It doesn’t take long to become proficient in identifying them. Then it’s just a matter of recognizing the other hawks that aren’t those three.
American kestrels are falcons. Two other falcons also migrate through Maine. A few merlins and peregrine falcons are likely to pass the top of Cadillac on a northwest breeze.
Merlins aren’t much bigger than kestrels, but they are substantially more powerful, dining more on birds and less on dragonflies. Thus, their flight style is less fluttery than that of their cousins. They seldom soar or glide, instead flapping steadily past the summit. Merlins are darker than kestrels, but that’s not apparent at a distance. Even the hawk watch experts on the mountaintop may not correctly identify them until they get a little closer.
Peregrine falcons are crow-sized. They have the same pointed wings of the other falcons, but bigger, letting them soar with ease. After you’ve seen a few kestrels and merlins, peregrines look like brutes. They’re hard to mistake.
Cooper’s hawks are accipiters, in the same family as sharp-shinned hawks. They are very similar in appearance, but larger. They have the same flap-flap-glide flight style. Books tell you to look for a bigger head protruding beyond the wings. Their tail ends are rounded, as opposed to the squared tails of sharp-shinned hawks. But on the mountaintop, I find that size matters most. Think blue jay. If an approaching accipiter looks bigger than that, suspect a Cooper’s hawk.
Incidentally, sharp-shinned and Cooper’s hawks are the ones that are most likely to flash through your yard during migration season. They’re just stopping in for a fast-food bite to eat, much to the consternation of mourning doves. Some linger into winter, in areas with a concentration of bird feeders.
Like the broad-winged hawks, red-tailed hawks are buteos. They are built the same way, able to glide, circle and soar more than the other hawks. They are bigger than crows, and much bigger than broad-winged hawks. When they pass the summit, there is seldom confusion about their identity.
Red-shouldered hawks are an intermediate size between their buteo cousins. They might cause identification trouble. However, very few migrate over Maine mountains. Don’t worry about them.
Northern harriers are almost as big as the biggest raptors. They have long wings and long tails. They’re easy. Don’t worry about them either. You’re welcome.
