50,000-mile round trip makes Arctic tern the ultimate commuter

[Donna]

Cheetah, killer whale, Arctic tern. The latter may sound an unlikely contender for nature’s greatest athlete, yet the small but elegant seabird migrates more than 50,000 miles every year — the longest trek of any creature, according to research.

The Arctic tern breeds as far north as the Arctic before flying tens of thousands of miles to Antarctica and back within a single year. By moving between Arctic and Antarctic summers, the bird sees more daylight than any other creature on Earth.

Until now, the birds had only ever been tracked as far as South Africa, through traditional bird ringing studies. “After that we lost them and we had no idea of how they got back up north,� said Carsten Egevang, of the Greenland Institute of Natural Resources in Nuuk, who led the research.

Using miniature geolocators to track 11 Arctic terns from colonies in Iceland and Greenland, Dr Egevang and colleagues were able to follow the birds’ complete route for the first time.

The findings, published today by the Proceedings of the National Academy of Sciences, showed that some individuals travelled more than 50,000 miles annually. “They’re the ultimate commuters,� Dr Egevang said. “This is at the edge of the capacity of any living creature.�

Previously, the furthest recorded migration was by the sooty shearwater, a seabird that makes a 40,000-mile circular trek each year from New Zealand to Alaska.

Arctic terns feed in shallow coastal waters on small fish such as sand eels, and nest on beaches and offshore islands. The British population breeds mostly around the north and west coasts, with the largest numbers in Scotland and Ireland. The terns reach their northern breeding grounds by May or early June, where each female lays one to three eggs in a hollow scooped out of sand. The young can fly after 21 to 24 days, but stay with their parents for a month or two.

After leaving their colonies, the study showed the terns flying southwest to make a previously unknown stopover in the Newfoundland Basin.

Despite there being no land mass for the terns to seek rest, they hovered over a region of deep water for about 25 days, taking advantage of a hotspot of sea life at the junction between cold northern waters and less biologically active southern waters.

From here the birds veered towards the West African coast. South of the Cape Verde Islands, seven of the tagged birds continued parallel to the African coast, while four crossed the Atlantic to follow the east coast of Brazil. All eleven birds spent the winter in the Southern Ocean before setting off once more in March. The 15,000-mile return to South Greenland took only 40 days.

Comparing the tracking data with satellite images showing marine biological activity suggests that the route is largely dictated by food availability.

Arctic terns are 13 to 15in (33-38 cm) long, grey and white, with a black crown and a bright red beak. Their 2ft wingspan is one of the largest relative to weight and equips them well for long-distance flight. Despite their extreme migration, relatively few terns die each year and the birds can live up to 34 years.

The birds could face even more extreme challenges during the ensuing decades, according to Dr Egevang. “Climate change is happening most rapidly at the Poles and the Arctic tern is one of the only species that spends significant amounts of time at both extremes. There is no doubt that it will be affected,� he said.

[gayle]

I have been privileged to see Arctic terns on several occasions in Alaska.  Here are several resting on a baby berg!  It boggled my mind to know that just a few weeks prior, those same birds had been resting on the ice of Antarctica!

Gayle

[gayle]

I have been privileged to see Arctic terns on several occasions in Alaska.  Here are several resting on a baby berg!  It boggled my mind to know that just a few weeks prior, those same birds had been resting on the ice of Antarctica!

Gayle

Sorry, but I don't have this posting business down pat.  If you click on the link, you will be able to see the image.

[Donna]

I have been privileged to see Arctic terns on several occasions in Alaska.  Here are several resting on a baby berg!  It boggled my mind to know that just a few weeks prior, those same birds had been resting on the ice of Antarctica!

Gayle

Sorry, but I don't have this posting business down pat.  If you click on the link, you will be able to see the image.

Gayle, can I help you with this? I don't see a link or pics. To post a pic, just click on additional options under post box. Then click on Browse and find your pic then click on it. All done!

[gayle]

[/quote]

Gayle, can I help you with this? I don't see a link or pics. To post a pic, just click on additional options under post box. Then click on Browse and find your pic then click on it. All done!
[/quote]

That is exactly what I did.  The link is at the lower edge of Reply #1.

[schlaf374]

Gayle,
As always, your picture was awesome! Thanks for sharing.
Linda

[Donna]

Gayle, can I help you with this? I don't see a link or pics. To post a pic, just click on additional options under post box. Then click on Browse and find your pic then click on it. All done!
[/quote]

That is exactly what I did.  The link is at the lower edge of Reply #1.
[/quote]

I am so bad....and sorry. I did not see that. Very nice. Forgive me.    

[MAK]

    I didn't see the link right away either.  Guess we should go see the eye doctor.