The arctic tern (Sterna paradisaea) is a seabird with migration patterns that cover nearly the entire earth. On average, arctic terns migrate over 44,000 miles each year from their arctic nesting sites during the northern hemisphere summer to their Antarctic homes during the southern hemisphere summer and back again, making for the longest migration of any bird on earth.
Arctic terns are white and grey birds 13-15 inches in length with a wingspan of just over two feet. The top of their heads are black with a red beak as long as the head itself. Adults have deeply forked tails and short red legs with webbed feet.
During the northern summer arctic terns can be found throughout coastal regions of northern Europe, Asia and North America nesting. Once the northern winter draws near, the terns will set out for their southern home in Antarctica. Because they fly with prevailing winds, the journey south may be up to 14,000 miles long. Whereas terns will stay on coastal land during the northern summer, they spend their time in Antarctica on and around pack ice during the rare times they’re not in the air.
Arctic terns are primarily carnivores and feed most often on small varieties of fish such as herring and cod, usually diving down to the surface to snatch the fish out of the water. In addition, arctic terns will also feed on crustaceans, berries and insects during the northern summer.
Once they have reached their third or fourth year of life arctic terns will begin breeding. Arctic terns mate for life and use elaborate courtship both in the air and on the ground to attract one another. Once a mate has been chosen, the couple will pick out a nesting site together; usually a simple depression in the ground in a rocky coastal area. The female will stay at this nest while the male catches food for her. After a few days of this, mating will occur and the female will lay a clutch of a few eggs about a month later. Incubation of the eggs is a task shared by both parents until the chicks hatch 22-34 days later.
The chicks are able to explore the nesting site on foot within a few days of hatching, and will be fed by both parents for their first month of life. After about a month the chicks are fledged and will be taught how to hunt by their parents before flying south for the winter. It is likely that all birds in the family will return to the same nesting site for the rest of their lives; an average lifespan of 20 years.
Arctic Tern Facts
Arctic terns can live up to 34 years.
An average arctic tern will fly over 1.5 million miles in its lifetime.
The Cornell Lab of Orinthology
Nova Scotia Museum of Natural History