For Wisdom the Laysan albatross, age truly is nothing but a number.

The 65-year-old bird has hatched a chick at the Midway Atoll National Wildlife Refuge in the Pacific Ocean -- at least her sixth since 2006. No bird was known to have achieved the same maternal feats when scientists first started squawking loudly about Wisdom four years ago. The average Laysan albatross dies at less than half her age, and scientists thought that albatross females, like other birds, became infertile late in life and carried on without producing chicks.

Obviously, those scientists were very wrong. The cute chick seen peeking out from beneath Wisdom is probably her 40th, biologists at the Bird Banding Laboratory at the U.S. Geological Services Patuxent Wildlife Research Center in Laurel, Md., said this week.

They know this because a USGS employee first clasped an aluminum band around Wisdom’s ankle in 1956. Still working for the government in 2001, that same biologist picked up a bird among the many thousands at the atoll and traced her dated tag to a signature he recognized — his own. That’s when scientists became giddy and gave Wisdom her name, estimating her then-age at 49.

There was a time when Wisdom was compared to a Northern Royal albatross named Grandma that was 61 when she produced a chick. But now Wisdom stands alone. Grandma hasn’t been seen at her nesting ground at Taiaroa Head, New Zealand, for about six years and is presumed dead.

When Wisdom returned to the atoll at the end of the Hawaiian island chain in November after her yearly flight around the globe, biologists shook their heads in disbelief. "It continues to just blow our minds," Bruce G. Peterjohn, chief of the banding lab in Laurel said at the time.

Her new baby, believed hatched around Feb. 1, is named Kūkini. It means "swift messenger" in Hawaiian.

Since the day she was first tagged, Wisdom has likely flown more than 3 million miles.  That’s “4 to 6 trips from the Earth to the Moon and back again with plenty of miles to spare,” according to the USGS.

“It is very humbling to think that she has been visiting Midway for at least 64 years," Deputy Refuge Manager Bret Wolfe noted when Wisdom laid an egg last year.

It's safe to say that most albatrosses of any type aren't doing this. Only two of 21 albatross species aren't threatened with extinction. The cause of their demise? Humans. Long-line fishing has depleted their numbers. Bait that fishermen throw into the ocean to lure fish also draw albatrosses that get hooked and drown.

Another problem is marine garbage. About five tons of plastic is unknowingly fed to albatross chicks each year by their parents, the USGS estimates. Often, it's a slow death that restricts the nutritional intake of babies, leading to dehydration.

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