On a blustery Sunday along the Glenn Highway at mile post 119, a crowd of cars, lawn chairs and barbecue grills clutter the pullout. Two hours from Anchorage, these wildlife spies wait for a show.
But it was not a show of the silver screen variety. This particular viewing opportunity is a rare treat for birders, as migrating raptors (hawks, eagles and falcons) move northward.
I decided to see for myself.
Gunsight Mountain, is not only one of the northern-most hawk-watching sites in the world, but it is also a spot that offers unique lighting. Because so much snow still covers the ground, the sunlight reflects back up into the sky like a searchlight, illuminating the birds from below. This makes it much easier to see identifying marks, and helps viewers spot light-colored birds as they flash brilliant white overhead.
Hawks, eagles, and falcons often migrate in large numbers, like long strings of birds stretched along the mountainous ribs of the continent. In Alaska, most of the raptors that breed here head south for the winter. Some birds head to the Midwest or to the Gulf Coast. Others stay on the Pacific Coast. From late March to early May, they wing their way back north. On high-traffic days, several hundred birds glide over the Gunsight Mountain pullout, where I sat in waiting.
About 11:30 a.m., hawks start trickling past. These raptors take practice to identify since they vary greatly from dark to light versions of their patterns. These first birds come through low, providing fantastic views of their markings. First, I spot a classic light-colored Rough-legged Hawk which is brilliant white underneath, with large dark patches on its "wrists," a dark belly and dark outlines around the wings and tail. It sailed past without twitching a wing. A second and third bird soon followed. These two are dark-colored Harlan's Hawks, a western subspecies of Red-tailed Hawk. Harlan's Hawks usually have a white tail, sometimes with a hint of rusty pink, and a "T" formed by a dark belly and the top half of their wings. Dark wing tips and a dark outline of the back edge of their wings complete the ensemble. Gunsight Mountain is one of the best places in the country to see unusually high concentrations of Harlan's Hawks.
Gear is absolutely vital for this mission. I noticed everyone wearing binoculars and spied a flock of small telescopes on tripods set up at one end of the group. So at the minimum, grab a good pair of binoculars. A spotting scope (one of those small telescopes) is helpful too, although it takes some practice to focus on a moving target.
Scanning the sky with just your eyes is a good way to start, since it allows a wider field of vision than binoculars. Once you spot a suspicious speck in the sky, keep your eye on it and bring your binoculars up to your face. Your tactics may need to change later in the day, however, if the birds start flying higher. Then, you'll need to scan the sky through your binoculars to spot any birds trying to sneak through above your radar.
How they do it
From the largest eagle to the smallest falcon, these birds follow the mountains to catch a ride in the fast lane. And, they aren't early risers (which is good for some sleepy wildlife spies). The birds are using air currents to save energy and travel further. They wait for the air currents to start moving. Earlier in the day, when they fly closer to the ridge line, they're riding air deflected upward after hitting the mountainside. Chains of ridges provide a highway of rising air the birds can follow, only flapping now and then.
Thermal soaring is another style of travel. Later that afternoon, I needed binoculars to glimpse the tiny smudges of even the largest hawks and eagles. Thermals occur when the ground heats at different temperatures, causing columns of rising warmer air. Raptors ride these invisible elevators to higher altitudes, then glide until they find another. Another clue to when birds are catching thermals is what's called a "kettle." We watch groups of half a dozen hawks gather in a tight spiral over one point on the ridge, circling higher and higher, looking like a boiling kettle of water until one by one they shoot off nearly in a straight line along the spine of the ridge.
The wind picks up later in the afternoon, and I nearly do a backbend as I strain my eyes to catch the stream of Bald Eagles, Golden Eagles, Harlan's Hawks, Northern Harriers and Sharp-shinned Hawks passing directly above. For a few hours mostly hawks pour past, one after another, so many that it's difficult to look at one for more than a few seconds. This is barely long enough to identify it, before someone called out they've spotted another. The tally by the end of the day ends up more than 450, with 350 Harlan's Hawks being counted.
Gunsight Mountain was definitely a stakeout that paid off.
Beth Peluso is a freelance writer, illustrator and avid birder.