Every fall, billions of birds disappear from backyards and skies—but many are traveling thousands of miles using navigation abilities scientists are still studying.
Some Fly Thousands of Miles
More than 300 North American bird species are long-distance migrants. Arctic Terns and Sooty Shearwaters can travel more than 31,000 miles in a year, while tiny songbirds can cross roughly 700 miles of the Gulf of Mexico in a single flight.
Many Navigate at Night
Most migrating birds travel after dark, when conditions are cooler and predators are less active. Night-flying species can use the stars as a compass, detecting the rotation of the night sky to establish direction.
They Can Sense Earth’s Magnetic Field
Birds have a remarkable ability called magnetoreception that helps them detect Earth’s magnetic field. Research suggests some birds may use specialized visual systems to sense magnetic information, giving them another navigational cue when flying through darkness.
Rivers and Mountains Can Become Road Signs
Birds don’t rely on one navigation system. During daylight, some species follow recognizable landmarks such as mountain ranges, coastlines, rivers and valleys. North America’s major migration routes even include established flyways along the Atlantic and Pacific coasts and through the Mississippi River Valley.
Scientists Can Actually Track Them
Researchers now follow individual birds using tiny tracking devices, automated radio-telemetry stations and other technologies. Audubon’s Bird Migration Explorer currently includes tracks from 17,658 individual birds representing 232 species, giving scientists an unprecedented look at where migrants travel and where they stop to refuel.
Sources
- Cornell Lab of Ornithology — bird migration and navigation research
