by Denny Olson
Once again, the summer sneaked away with busy-ness, and it is Jewel Basin Hawk Watch (JBHW) time. A number of us addicts will soon be sitting on what seems like the top of the world, straining eyes to the north, watching for approaching dots in the sky, and testing ourselves with the challenge of getting a hawk, eagle or falcon ID correctly — with minimum information.
Even for reasonably good birders, identifying raptors as they fly by overhead (at 100 mph-plus!) can be intimidating. But if you are interested in getting better at it, ‘ya gotta start somewhere’. I’ll try to help by eliminating the “noise” of looking at the whole bird and not knowing where to concentrate for ID purposes. There are lots of people better at it than I am (Dan Casey, Josh Coville, Lisa Bate, BJ Worth all come to mind), but I’m having fun in the “student” role.
The 17 most common fall raptor migrants here in the Flathead fall into basic family categories of Accipiters (3 species), Buteos (5 species), Eagles (2), Harrier (1), Vulture (1) and Osprey (1). The Falcons (4) are birds of prey but not in the grouping of “hawks”. They are most closely related to parrots and other songbirds (even hummingbirds!).
One of the strategies I’m coming to appreciate is that your overhead look will be very brief, and usually with poor light adding to the difficulty. And, there can be three to five birds arriving almost simultaneously! So, when the birds are still a mile out, with only a head-on view available, what can you decipher?
The Accipiters (3 kinds), with their short wings and long tails, will be doing some variation of repetitive flap-flap-flap-glide. Sharp-shinned Hawks are small, get bounced around a lot in the breeze, and their heads seem small as they get closer. Heavier Cooper’s Hawks drive steadily through a medium breeze, and their heads are larger by comparison. They also have a slightly longer, more rounded tail with more white showing at the tip. Larger Goshawks have a stiffer, slower, more powerful wingbeat, lift their wings higher on the upstroke, and the wings are more pointed when flying than their smaller cousins. They also have longer secondary feathers on their inner wings, which make the wings look more pointed.
The Buteos have large broad wings and shorter tails, and hence are prone to more circling and soaring. Red-tails have a slight dihedral (“v” shape) of their wings when soaring. Because they are heavier than most other buteos, their wingbeats are heavy, but fluid-looking. At JBHW, there are always some “resident” Red-tails circling and hunting. The migrators fly straight south, like they are all business and on a mission.
Most of the Buteos are similar enough at a distance so that overhead field marks become more important. Look for dark leading edge of wings and the “comma” farther out on Red-tail wings. Juveniles won’t have the orange tail. Swainson’s Hawks have a light bouncy flight, and are the only raptors with a dark trailing edge on their wings. Ferruginous hawks — our largest buteo — have long tapered wings. They are usually very light colored (90%), and adults have a distinctive dark “V” of dark feathers where their legs come together in flight. They also soar with a “modified” dihedral, bending their wings flat at the “wrist”. Rough-legged Hawks, our far northern migrant, soar with a dihedral and tip back and forth in winds like a Harrier. Their dark “square” at the bend of the wing is a dead giveaway overhead. Broad-winged hawks — an eastern bird which we have seen more of lately — have a coarse banded tail and light underside with black edges around the entire wing.
More next time about the falcons, eagles, harriers, ospreys and vultures!
(If you can hike 2 hours with moderate but constant elevation gain, you owe it to yourself to visit the spectacular JBHW site!)