Old Bird Lays Egg at 60
She's the grand old lady of albatrosses, is still raising chicks and doesn't look a day older than she did in 1956.
Researchers call her Wisdom, and at 60 years of age she was recently found sitting on an egg on Midway Atoll, an island in the Pacific Ocean near Hawaii.
In fact, researchers didn't recognize her as the old gray dame of the isle at first, because she just didn't look the part. Not a trace of gray in the feathers, and no tiredness around the eyes.
"That is part of the amazing thing about this," said Bruce Peterjohn, chief of the U.S. Geological Survey's Patuxent Wildlife Research Center. "Fifty-five years after she was initially banded, she looks the same.
"Here is a bird that is a minimum 60 years old and basically hasn't changed and can go very readily and raise and produce young," he said.
Most albatrosses on islands in the northwest Hawaiian chain seem to live 30-40 years.
"Based on the banding data we have, she seems to be a fairly exceptional age," he said. "This is well beyond the average lifespan of an albatross."
That means she has probably outlived at least a couple of mates, though researchers cannot say for sure because they have no way to track her partners over time.
Peterjohn said she has likely raised about 30 chicks in her life.
He said researchers have known about the long-lived white bird since 2002, when they went back to their records after re-banding her and found that she had been first tagged by researcher Chandler Robbins in 1956.
Robbins is a well-known bird expert, now aged 92, and is the author of the bestselling book "Birds of North America: A Guide To Field Identification."
He said he did not know the bird by sight the last time he saw her.
"I didn't recognize it when I recaptured it in 2002 because it didn't have my bands on it, it had other people's bands," Robbins told Agence France Presse.
"And it wasn't until I got back to the office and checked the bands that I discovered it was one of mine from way back. So I didn't even take a picture of it at that time."
Peterjohn said researchers soon realized they had tracked the oldest known albatross in North America, and that she was probably about 52 years old in 2002.
"Since then we have been keeping closer track of her status on the island."
Birds tend to get re-banded about every 10 years, when the aluminum rings wear out and need a replacement. Bird trackers now use harder metal alloy they hope will last longer.
Wisdom's latest band is printed in big type.
"This particular bird now has a special band with larger letters so they can read it without recapturing her," said Robbins.
Peterjohn said researchers believe she laid the egg on her own, and did not adopt it from another bird.
They don't yet know if the fledgling that hatched from it is male or female. The chick will likely stay with its mom until June or July, when it gets old enough to fly off on its own, Peterjohn said.
Wisdom is a Laysan Albatross, which is listed as a "near threatened" species by the International Union for the Conservation of Nature, an improvement from its previous classification as "vulnerable" due to a recent population rebound.
"The population is estimated to be 590,926 breeding pairs, with the largest colony at Midway Atoll, followed by Laysan Island, both in the Northwestern Hawaiian Islands," the IUCN said.
Peterjohn said Wisdom's story may draw more interest in the study of the two-toned albatross.
"It just raises lots more questions. Is this truly an exceptional age? Or if more birds get banded and are followed closely through time, would this be a pattern followed by a greater number of birds?"
As to the albatross's method of staying young so long, Robbins said that will likely remain the bird's secret.
"They all look the same. It is only people that look old," he said.
Source: Agence France Presse
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