Pole to pole, the extraordinary migration of the Arctic tern
Bird travels equivalent of three round trips to the Moon in its lifetime
A sea bird famous for its long-distance migrations between the North and South Poles makes the equivalent of three round trips to the Moon in its lifetime, scientists have found.
The Arctic tern makes a return trip of around 44,000 miles from pole to pole each year, flying between its breeding grounds in Greenland in the north and the Weddell Sea on the shores of Antarctica in the far south, in a lifetime spent in perpetual summer.
Small tracking devices attached to the terns' legs have allowed their movements to be monitored in more detail than ever before. Scientists from the British Antarctic Survey found that the birds do not immediately head south from Greenland, but first spend almost a month at sea, in the middle of the North Atlantic, before continuing down the coast of north-west Africa.
Around the Cape Verde Islands, the researchers were surprised to find that about half the birds carried on south along the African coast while the rest crossed the Atlantic to follow a parallel route down the east coast of South America.
All the terns studied escaped the northern winter by flying to Antarctic waters, where it is summer at that time of year. On the return trip, they again did not take the shortest route, but traced a giant 'S' shape.
These diversions took advantage of prevailing global wind systems to help the birds preserve energy, according to Carsten Egevang, from the Greenland Institute of Natural Resources.
"They paused in their southward migration to spend time in highly productive waters in the middle of the Atlantic Ocean," he said. "Clearly, Arctic terns have learned to 'fuel up' before crossing areas of ocean with limited foraging options."
Arctic terns feed from the water while on the wing and can live up to 34 years. When the scientists added up the total distance each bird flew during its lifetime they found it equalled three round trips to the Moon – or more than 1.25 million miles.
The findings are published today in the journal Proceedings of the National Academy of Sciences.
Plastic rubbish heaps at sea pose bigger threat to Earth than climate change, claims ocean expert
Silence to mark the 100th anniversary of the death of last ever passenger pigeon
The top 10 weirdest animal mating rituals
The ugliest animals on earth: Blobfish, axolotl and proboscis monkey battle it out to be named least attractive beast
Potatoes could be off the menu as crop pests threaten UK
- 1 Emma Watson on Jennifer Lawrence naked photo leak: 'Even worse than seeing women's privacy violated is reading the comments'
- 2 Saudis risk new Muslim division with proposal to move Mohamed’s tomb
- 3 A teacher speaks out: 'I'm effectively being forced out of a career that I wanted to love'
- 4 Cee Lo Green: It is only rape if the victim is conscious
- 5 Katie Hopkins breaks down in tears over weight gain challenge: ‘I hate fat people for making me do this’
Rotherham child sex abuse scandal: Labour Home Office to be probed over what Tony Blair's government knew - and when
What do immigrants really think of Britain? Polish immigrant's Reddit post goes viral
Ashya King: Parents of five-year-old boy refused permission to visit him in hospital and denied bail at Spanish court
With Douglas Carswell joining Ukip, my party has taken another giant step forward
When elitism grips the top of British society to this extent, there is only one answer: abolish private schools
Ashya King: 'Cruel NHS has not given us the treatment we need', says father of five-year-old with brain tumour who fled to Spain
£30000 - £45000 per annum + benefits+bonus+package: Harrington Starr: Front-Of...
£700 per day: Harrington Starr: Quantitative Developer C++, Python, STL, R, PD...
£700 per day: Harrington Starr: Java/Calypso Developer Java, Calypso, J2EE, J...
£500 per day: Harrington Starr: SQL Developer SQL, C#, Stored Procedures, MDX...