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Albatrosses in Flight

 
 
gollum
 
Reply Wed 1 Oct, 2008 06:42 pm
How long can an albatross stay aloft
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Type: Question • Score: 0 • Views: 1,976 • Replies: 5
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chai2
 
  2  
Reply Wed 1 Oct, 2008 08:28 pm
For months at a time.

No kidding.
roger
 
  2  
Reply Wed 1 Oct, 2008 10:09 pm
@chai2,
If you'd ever see one trying to land, you would understand why they stay airborne.
dyslexia
 
  2  
Reply Wed 1 Oct, 2008 10:12 pm
@roger,
I keep one tied around my neck, it keeps me light on my feet.
Merry Andrew
 
  1  
Reply Wed 1 Oct, 2008 10:15 pm
@dyslexia,
Thought you wuz an ancient cowboy, not an ancient mariner.
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chai2
 
  1  
Reply Thu 2 Oct, 2008 10:45 am
I read a national geographic article about them and they truely are amazing creatures. Also looked up on the internet.

When they are gliding on the drafts, there is a tendon that snaps and locks into place, so they don't put any effort into keeping their wings open.

They prefer staying in the air, coming ashore only to breed and lay their eggs.

Albatross Wanders Far Afield
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LinkedinDiggFacebookMixxYahoo! BuzzPermalinkBy WALTER SULLIVAN
Published: March 20, 1990
LEAD: By attaching radio beacons to wandering albatrosses and monitoring them by satellite, French researchers have found that circular foraging flights by the birds sometimes exceed 9,300 miles, more than eight times the distance that had been assumed. In some cases they cover 560 miles a day.

By attaching radio beacons to wandering albatrosses and monitoring them by satellite, French researchers have found that circular foraging flights by the birds sometimes exceed 9,300 miles, more than eight times the distance that had been assumed. In some cases they cover 560 miles a day.

This was the first time such monitoring has been possible. The birds fly so far that the curvature of the Earth puts them beyond range of land-based radio receivers. The researchers hope that satellite tracking can explain why the wandering albatross and its cousin, the Amsterdam albatross, are threatened with extinction.

The wandering albatross is the largest marine bird, with wingspans reaching 11 feet. It is a glider, swinging back and forth with its wingtip almost touching the waves. Until now, little has been known of how it survives such long flights.

The birds nest on sub-Antarctic islands, with mating partners taking turns making long expeditions to eat while the other incubates the egg. One of the monitored flights lasted 33 days, and large males were seen to sit on an egg for at least 55 days before their mates returned. For as long as it sits on the egg, the big bird does not eat.

Six-Ounce Transmitters

Once the egg has hatched, the foraging trips last only two to four days. The parent bird eats, then returns to the nest to provide a regurgitated meal to the chick.

Six male birds from a colony on Possession Island in the Crozet Islands, a French possession midway between Africa and Antarctica, were tagged with six-ounce radio transmitters. These were monitored by one or the other of two satellites.

''Both the distances covered and the long-distance flight speeds were much higher than the highest estimates for this or any other species of bird,'' the researchers reported Feb. 22 in the journal Nature. The birds, which weigh about 25 pounds, flew up to 50 miles an hour and could sustain an average hourly speed of 35 miles for a distance of 500 miles.

Of the six birds fitted by the French with beacons, five returned to relieve their mates. The sixth had not come home by the time the beacon's battery was presumably exhausted.

During the day the birds were almost constantly on the move, apart from short stops when they may have been feeding. At night they stopped to rest on the water's surface for longer periods, though rarely for more than an hour. They were particularly active on moonlit nights.

Concentrated Oil for Chicks

In earlier research, P. A. Prince and R. A. Morgan of the British Antarctic Survey, who conducted their study in South Georgia, said much feeding by the wandering albatross takes place at night. Because the bird raises its chick in the dark of the Antarctic winter, little is known of its feeding habits.

Squid, the birds' primary food, tend to come to the surface of the water at night, where they are scooped up by hungry birds. The albatross also eat krill, fish and sometimes garbage from ships, according to the British study. Part of what the albatross eats is reduced to a concentrated oil so it can be carried long distances to feed the chicks.

The French researchers noted that the Southern Ocean, bounded on the south by Antarctica and on the north by Africa, Australia and South America, is subject to stronger and more regular winds than any other part of the world. The monitoring showed to what an extent the birds are dependent on high winds. Wind direction along each flight path was determined from reports twice a day by the Weather Bureau in Melbourne, Australia. This showed that the giant birds almost never fly upwind. They tended to set out eastward from Crozet, riding the prevailing westerlies of that region.

One then ranged north into subtropical waters; another turned south, returned along the coast of Antarctica, and circled back to Crozet. If faced with a headwind the birds tacked back and forth like a sailboat.

The French report was by Pierre Jouventin and Henri Weimerskirch of the Center for Study of Wild Animals in Beauvoir, France. The British researchers contributed to a book, ''Seabirds Feeding Ecology and Role in Marine Ecosystems,'' published in 1987 by Cambridge University Press.
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