Archived Outdoors

The Naturalist's Corner: The skies are beginning to fill

Cape May warbler in fall plumage - Ridge Junction September 2017. Don Hendershot photo Cape May warbler in fall plumage - Ridge Junction September 2017. Don Hendershot photo

Around 70 percent of the birds that nest in the Eastern U.S. are neotropical migrants — they nest here (U.S. and Canada) and overwinter in Mexico and/or Central and South America. There are around 200 species of neotropical migrants and many make extensive journeys. Shorebirds nesting in the arctic tundra and northern Canada have the longest migration. Species like red knots and white-rumped sandpipers may travel 10,000 miles between nesting and wintering grounds. Long distance migrants that nest in our area include red-eyed vireos, barn swallows, cerulean warblers, scarlet tanagers and more.

Most passerine (songbird) species migrate at night. Conditions are more favorable at night; temps are cooler, the air is usually calmer and there are fewer predators. Neotropical migrants that migrate during the day (diurnal migrants) are hawks and vultures — birds that soar. These soaring birds migrate by finding thermals (rising currents of warm air) where they can hitch a ride while conserving energy. Most swallows and swifts are also diurnal migrants because they feed on flying insects that are active during the day.

Weather conditions often dictate the altitude of migrating birds. Most raptors stick pretty close to terra firma because that’s where the thermals are. However if they catch a good thermal they could rise more than a mile high. Nocturnal migrants with a good tailwind migrate at higher altitudes because the wind is stronger at higher altitudes. 

Conversely, if they have to buck a headwind they migrate at lower altitudes. Most passerines migrate at altitudes between 500 and 2,000 feet. The highest known migrant was a Ruppell’s griffon vulture recorded at 37,000 feet, and the North American record holder is a mallard that, unfortunately, collided with an airplane at 21,000 feet.

Birds use a variety of factors to navigate. Some navigating tools include stars, the earth’s magnetic field, topographic features (coastlines, mountain ranges, etc.) the location of the setting sun and prevailing wind patterns.

And one thing birders know about migrating songbirds — a “fall out” can be dizzying. Many different species often flock together during migration, and after a long night of flying they’re pretty hungry in the morning. These mixed flocks can be found foraging together in the trees and understory. Trying to pick out individual birds to I.D. when there may be 20 in your field of vision all fluttering and/or hopping about requires a little practice and patience.

Related Items

Identifying fall migrants adds another challenge too. Fall plumage can be quite different from breeding plumage, and during migration there will be individuals in different stages of molt. Some may still be in breeding plumage, while others may be already sporting winter plumage and many will be somewhere in between.

And now for some unadulterated pandering. I will be leading a trip for Alarka Expeditions, along with Brent and Angela Faye Martin, to Ridge Junction Overlook along the Blue Ridge Parkway at the entrance to Mount Mitchell State Park on Saturday, September 29. Ridge Junction is unique because, much like a hawk watch, you can bring a chair and get comfy at the overlook and wait for migrants to come through the pass up and over the Parkway. For details about the trip contact Brent or Angela at This email address is being protected from spambots. You need JavaScript enabled to view it. or call 828.524.7400.

(Don Hendershot is a naturalist and a writer who lives in Haywood County. He can be reached at This email address is being protected from spambots. You need JavaScript enabled to view it.)

Smokey Mountain News Logo
SUPPORT THE SMOKY MOUNTAIN NEWS AND
INDEPENDENT, AWARD-WINNING JOURNALISM
Go to top
Payment Information

/

At our inception 20 years ago, we chose to be different. Unlike other news organizations, we made the decision to provide in-depth, regional reporting free to anyone who wanted access to it. We don’t plan to change that model. Support from our readers will help us maintain and strengthen the editorial independence that is crucial to our mission to help make Western North Carolina a better place to call home. If you are able, please support The Smoky Mountain News.

The Smoky Mountain News is a wholly private corporation. Reader contributions support the journalistic mission of SMN to remain independent. Your support of SMN does not constitute a charitable donation. If you have a question about contributing to SMN, please contact us.