Back in 2010, new knowledge on the migration of the Arctic tern was published in the scientific journal PNAS. The study was part of my PhD focusing on the Arctic tern in Greenland and revealed longest annual migration ever recorded in any animal. The annual roundtrip of the Arctic tern is more than 71,000 km. From ringing recoveries, it is known that Arctic terns can reach an age of more than 30 years. The total distance flown in a tern’s life may exceed 2,4 million km., which is equivalent to 3