Hawk Migration: A Fall Phenomenon

Hawk Migration: A Fall Phenomenon

Broad-winged Hawk flight

By Winslow Umberger

It’s a thing. People spending hours simply staring at the sky from a Parkway overlook. Our mountain sky-gazers greatly increase in number during the last two weeks of September—the peak of the Broad-winged Hawk migration. It is one of the most incredible spectacles Nature has to offer: thousands of raptors soaring south on their way to the Amazon.

Vicky Burke, a lifelong birding enthusiast, wouldn’t miss it. “The Broad-winged Hawk migration is the one everyone gets the most excited about,” she says. “This species migrates in large groups (called kettles). While a small kettle numbers between 50-300, kettles can contain thousands. Most people don’t see a group of 50 hawks at any time in their lives, let alone thousands!”

The annual southward migration of millions of birds typically starts in late August/early September and continues until November, says Mathias Engelmann of the Carolina Raptor Center. “Each species has a peak season. People can expect to see Sharp-shinned, Cooper’s, Broad-winged, Red-shouldered and Red-tailed Hawks as well as Turkey Vultures, Ospreys, Bald Eagles, Northern Harriers, Peregrine Falcons, Merlins and American Kestrels. One might occasionally see a rare species, like Golden Eagles.”

He happened to be in the right place at the right time to witness this spectacle. Many years ago, Engelmann was fortunate enough to be at Mahogany Rock Overlook on a perfect day when more than 8,000 Broad-winged Hawks passed overhead.

“It’s a very weather-dependent migration,” says Bill Sanderson, founder of the Mount Pisgah Hawk Watch. “The best time to see migrants is the three days following the passage of a low pressure front (which usually brings winds from the northwest/ west). Overcast or partly cloudy skies are much better than clear skies. Birds disappear in a clear sky, but if you have high clouds overhead they are silhouetted so that you can pick them out easier.”

Burke says that a “perfect storm” happened in 2018. “There had been several hurricanes in a row that kept the hawks pushed back. When the weather broke, they started moving. All of a sudden I spied a mass of hawks coming over the distant mountaintops heading our way. Within minutes they were soaring over us. We counted about 4,500 hawks! It was over in half an hour.”

Why are the mountains favored with this phenomenon? “Birds use mountain range ridgelines as a guide and the updrafts created by them to conserve energy,” says Engelmann. When the thermals rise, the raptors rise with them until the air cools. At that point, they will glide out of it, only to catch and ride another thermal, always riding the wave forward.

Burke counts hawks for the Hawk Migration Association of North America (HMANA), stepping in where Sanderson left off. For the past two years, she has been managing the Mills River Valley Overlook site, recording data for HMANA. “The Mills River site, located at MM404.5, is the only overlook in the region with views on both sides of the ridge, so it’s ideal for watching the migration,” says Sanderson. “If an official counter is at the overlook, anyone is welcome to set up their chair and join in.”

A folding chair is essential hawk-watching equipment, along with sunglasses, sunblock, water, snacks and a hat. Binoculars help too, but if someone doesn’t have them they will still see plenty of birds, assuming that they are moving that day. It is likely that Burke will be there to answer questions, but she also welcomes questions via her email at And she reminds us that the day will not be lost if no hawks are spotted, as being in a peaceful setting surrounded by beautiful scenery is reward enough.

Winslow Umberger is head of outreach for Appalachian Wild, a 501(c)3 nonprofit whose mission is to help injured and orphaned native wildlife, support licensed home-based wildlife rehabilitators and provide conservation education. To donate or volunteer, visit

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