While almost all birds migrate between seasons, few take it as seriously as the Arctic Tern, a small seabird that flies a distance of between 70,000 - 81,600 km annually, from its breeding grounds in the Arctic to its winter home in the Antarctic.

While the distance, the longest known migration pattern of any animal, is remarkable, it is even more so, given that this tiny bird weighs a mere 100 grams or 3.5 ounces. Researchers estimate that during the Arctic Tern's lifespan, which could be as long as 34 years, the diminutive bird travels the equivalent of three trips to the moon and back!

These fascinating migratory findings are the result of The Arctic Tern Migration Project, a multi-year undertaking by the scientists at The Greenland Institute of Natural Resources. Using really tiny geo-locaters they tagged 20 Arctic Terns in Northwest Iceland and 50 in Greenland in 2007.

They then waited a whole year, in the hope that not only would some of the birds return, but that they would be able to catch them and retrieve the locators -That's because while these tiny devices can store the data, they are unable to transmit it.

Fortunately for them, some of the birds did return, and they were able to snag ten of them and re-trace their trip. Besides finding out that these birds travel almost twice the distance they had originally estimated, they also made another amazing discovery.

The Arctic Tern makes a 3,000 km detour on its way to the Antarctica in Autumn - stopping for a mini vacation for about 25 days near Newfoundland to fish for Krill. From there, some fly over the coast of West Africa, while others go along the coast of South America, to get to their final destination. The return trip however, is made on a 'shorter' more direct route and in sync with the prevailing winds so that the flying is easier.

The new findings have been very enlightening as it provides scientists an amazing insight into the behavior of birds that migrate for long distances. It also usurped the previous 'commuter King', the Sooty Shearwater, a seabird that travels 64,000 km every year from New Zealand to the sub-Arctic waters.

sources:newscientist.com,gizmag.com