Bird of the sun

The Arctic tern is known to make the longest annual migration in the animal kingdom. During its breeding season, it is found far to the north where summer days are long, and it winters far south in the southern hemisphere, where the days are longest during November to February. This means that the Arctic tern probably experiences more sun light during a calendar year than any other creature on Earth. The long-distance travel of the Arctic tern is well-known both amongst researchers and in the broader public. Now, for the first time, technological advances allow us to follow the Arctic tern on its immense journey, practically from pole to pole.


The Arctic tern (Sterna paradisaea) is a medium-sized seabird with an average mass of 95-125 g and a wingspan of 75-85 cm. The species has a circumpolar breeding distribution, breeding colonially in Arctic and sub-Arctic regions of Europe, Asia, and North America, with the largest colonies found located in Greenland and Iceland. They lay one, two, or sometimes three eggs in a small scrape on the ground, making the Arctic tern particularly vulnerable to predatory mammals, including the Arctic fox.

The Arctic tern has an opportunistic feeding strategy, with small fish and crustaceans being the most common prey items. They forage by plunge-diving and surface dipping, finding their food items in the upper layer (top 50 cm) of the water column. Like other seabirds, Arctic terns are generally long-lived, and the oldest known individual reached the ripe old age of 34 years.


The Arctic tern has an opportunistic feeding strategy, with small fish and crustaceans being the most common prey items. They forage by plunge-diving and surface dipping, finding their food items in the upper layer (top 50 cm) of the water column. Like other seabirds, Arctic terns are generally long-lived, and the oldest known individual reached the ripe old age of 34 years.

The Arctic tern is notorious for its long-distance migration between the breeding grounds and the winter quarters in the Southern Ocean. This knowledge has been obtained by ringing and observations of movements at-sea. Ringing recoveries of birds breeding in Europe and Greenland indicate that the birds migrate along the coast of Western Europe and West Africa during autumn, and reach South Africa in November. From there on ringing recoveries are very scarce, but the species is observed to winter in the Southern Ocean. The migration back to the breeding ground, however, was undocumented until now.