Which Bird Migrates the Farthest?

The Arctic tern (Sterna paradisaea) undertakes the longest migration of any animal, flying approximately 71,000 kilometers round-trip each year between its Arctic breeding grounds and Antarctic wintering areas. Over its roughly 30-year lifespan, a single tern may travel the equivalent of three round trips to the Moon. Researchers tracking terns with tiny geolocators found they don't fly in straight lines but follow an S-shaped route across the Atlantic, taking advantage of prevailing wind patterns. The birds experience two summers per year — one at each pole — and see more daylight than any other creature on Earth. Despite weighing only about 100 grams, they routinely cover over 300 kilometers in a single day.