How far can an Arctic tern travel during its annual migration between the Arctic and Antarctic?

An Arctic tern can travel about 70,000 kilometres during its annual migration between the Arctic and Antarctic.

This journey is one of the longest regular migrations known in the animal kingdom. Arctic terns breed in northern regions during the Northern Hemisphere summer, then fly south to Antarctic waters for the Southern Hemisphere summer. They therefore experience two summers each year and more daylight than almost any other animal.

The exact distance varies because birds do not follow a straight line. Many use routes over the Atlantic or Pacific and take advantage of prevailing winds. Modern tracking studies have shown that some individuals travel considerably farther than the traditional 70,000-kilometre estimate.

The species is often confused with other terns because of its slim body and forked tail. Its long migration is different from a simple north–south flight: the route may include major detours, feeding stops and wind-assisted passages.