N N Naturalist NoteS By Danielle Oyler, Institute Resident Instructor
Over Yellowstone Ospreys chirp as you view the Lower Falls of the Yellowstone River.
Western meadowlarks sing as you scan Lamar Valley for elusive canines.
Birds are part of the fabric of our Yellowstone experiences, and many Yellowstone birds are making long and strenuous voyages this fall. Birds migrate in order to find enough food and the right habitat to sustain them. Due to our harsh winters and the accompanying lack of food, a majority of Yellowstoneâ€™s summer birds cannot live here year-round. Some travel a few miles, others to another hemisphere, to reach good wintering grounds. Swainsonâ€™s hawks, for example, live in Yellowstone in summer and travel more than 6,000 miles each way to spend the winter in the Pampas of Argentina. Birds have many adaptations to accomplish their strenuous migrations. Hyperphagia, an increased appetite, is something we normally associate with autumn and bears in Yellowstone. Some birds also go through hyperphagia to put on more fat as fuel for long journeys. Taking advantage of wind patterns also helps birds move efficiently. Hawks, pelicans, and cranes use daytime winds. Warm air rising during the day acts like an elevator for these birds and helps them save energy
as they glide on thermals.
Most passerines, or perching birds, prefer to travel at night. Night brings calmer, cooler, and more predictable conditions for these smaller birds. These are just a few of the ways that our adaptable birds overcome the challenges of migration. This fall,
look to the skies, and you might find your own piece of Yellowstone, a migratory bird bound for its winter home.