66-year-old seabird is expecting: More about world's oldest known breeding bird

Wisdom, the oldest known seabird in the world, has returned to Midway Atoll National Wildlife Refuge and Battle of Midway National Memorial with her mate Akeakamai. And the 66-year-old hasn't just returned, but is incubating an egg.

Wisdom was first banded (Z333) in 1956 by biologist Chandler Robbins and is believed to be the world's oldest known breeding bird in the wild. She has been returning to Midway for more than six decades now and has bred a few dozen chicks. Laysan albatrosses start breeding after the age of five and some take even up to 10 years. But Wisdom had already started breeding in 1956, which means she is 66 or more.

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Many albatrosses take a year off from breeding to invest time and energy in molting, so Wisdom was not expected to breed this time. But to the surprise of everyone, she has returned to the same nest that she has been using each year with her mate Akeakamai and laid an egg. She fledged a chick, Kukini last year.

"I find it impressive that not only has Wisdom returned for over six decades as the oldest living, breeding bird in the wild, but also that biologists here on Midway have been keeping records that have allowed us to keep track of her over the years," Charlie Pelizza, U.S. Fish and Wildlife Service Acting project leader said in a statement.

"When I made it to lunch, I knew something was up. The staff was abuzz with the news that Wisdom was back and incubating. It's amazing what a bit of good news can do to brighten the day."

Wisdom is expected to incubate the egg for a couple of days until her mate returns and takes up the responsibility of incubation. She will then leave for the sea to refresh herself.

(Source: USFWS)