The Arctic tern is a seasoned traveler. It breeds in the Northern Hemisphere, mostly within the Arctic Circle, but flies to spend the northern winter in the Southern Hemisphere, mostly in the Antarctic ice-packs. This journey to the Antarctic enables the Arctic tern to enjoy the benefits of a second summer with its long days and plentiful supply of food.
The round-trip journey between Arctic and Antarctic is 35,000 km (21,750 miles) -- roughly the same distance as the entire circumference of the earth. Considering that some Arctic Terns live 30 years or more, this means that they have traveled over 1 million km (over 650,000 miles) in their lifetime. For birds that are only 38 cm long and 300 gm in weight, this is no mean achievement!