At age 64, the world's oldest tagged bird is ready to have another baby. The Laysan albatross named Wisdom recently returned to her nesting ground at the Midway Atoll National Wildlife Refuge over Thanksgiving weekend and mated. Any day now, Refuge workers expect her to back to lay her egg.

Wisdom has become something of an avian celebrity, not only having far surpassed the expected span of her hatchling-rearing days, but also living much longer than most other albatrosses.

"In the face of dramatic seabird population decreases worldwide -- 70 percent drop since the 1950s when Wisdom was first banded--Wisdom has become a symbol of hope and inspiration," Dan Clark, Refuge Manager, said. "We are a part of the fate of Wisdom and it is gratifying to see her return because of the decades of hard work conducted to manage and protect albatross nesting habitat."

Wisdom was first tagged in 1956, and because Laysan albatross do not return to breed until they are at least five years old, it is estimated Wisdom is at least 64 years old -- but she could even be older. While birds frequently lose their tags, Wisdom's band was continuously replaced to ensure meticulous record-keeping. Since 1956, researchers believe she has likely clocked over six million ocean miles of flight time.

Generally speaking, albatrosses mate for life, but Wisdom has likely had more than one partner and raised as many as 36 chicks. Male and female albatrosses typically spend six months tending to and feeding their young after it is born. The large sea birds reach sexual maturity around the age of five, but usually don't start breeding until they are seven or 10 years old.

Nineteen of 21 albatross species face extinction, with human-produced plastic pollution being the leading cause. However, Wisdom has defied all odds.

"She's the only one to live this long and avoid all the problems that confront [an] albatross," Bruce G. Peterjohn, chief of the Bird Banding Laboratory at the U.S. Geological Services Patuxent Wildlife Research Center, said. "Something could happen and they could find her dead on Midway. Someday she's going to fly off the island some spring and never come back."

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