Wisdom, the world's oldest known breeding and banded bird, first tagged in 1956, is still going strong in the fertility department.

According to the U.S. Fish and Wildlife Service's Pacific region (USFWS), the old girl has given birth to a new baby chick at her home base on a wildlife refuge on Hawaii's Midway Atoll – itself one of the oldest atolls in the world.

At least 66 years old, Wisdom, a Laysan albatross, was spotted last December on the atoll, where researchers were excited to find that she was incubating an egg. The proud papa is her mate Akeakamai (a Hawaiian word meaning "seeker of wisdom").

"Wisdom continues to inspire people around the world. She has returned home to Midway Atoll for over six decades and raised at least 30 to 35 chicks," said Bob Peyton, USFWS project leader for Midway Atoll Refuge and Memorial, in a statement.

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Albatrosses spend almost 90 percent of their lives in the air, logging thousands of miles of flight in search of food. The USFWS estimates that Wisdom has flown more than 3 million miles during her life. She comes back to the same nesting spot on the Midway Atoll most years, a site that is home to more than 3 million seabirds.

Wisdom is said to be "at least" 66 years old because it's just not possible to be exact, given her history. She was already breeding when she was tagged in 1956, and Laysan albatrosses are not sexually mature until at least age 5 and may not have chicks at all until 8 to 10 years old.

Wisdom is identified by the red, plastic auxiliary band on her right leg. Credit: Kristina McOmber/Kupu Conservation Leadership Program & USFWS

Wisdom and Akeakamai will stay on the atoll for about seven months while they raise the chick, expending lots of energy flying off to forage for food to feed the new mouth. It's such a time-consuming process that Laysans don't typically lay an egg every year.

That makes Wisdom's latest addition all the more special.

"Because Laysan albatross don't lay eggs every year, and when they do, they raise only one chick at a time, the contribution of even one bird to the population makes a difference," said Peyton.

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