WASHINGTON, Dec. 1 (UPI) -- The world's oldest tracked bird, a 64-year-old albatross named Wisdom, is back on American soil and she's believed to be carrying an egg.
After a year at sea, Wisdom was spotted on Nov. 19, 2015, among the dunes of the Midway Atoll National Wildlife Refuge. In the days following her arrival, wildlife managers observed Wisdom with her mate.
Wisdom was already the oldest bird recorded laying an egg, and now she's "nested consecutively."
"Wisdom left soon after mating but we expect her back any day now to lay her egg," Bret Wolfe, deputy refuge manager, said in a U.S. Fish and Wildlife Service blog post. "It is very humbling to think that she has been visiting Midway for at least 64 years."
Since she was banded in 1956, Wisdom has birthed and raised at least 36 chicks. As previous mates perish, Wisdom has taken on new ones, defying the odds. Most albatrosses don't live to be half Wisdom's age.
"We're learning what these birds are capable of doing at what we consider to be an advanced age," said Bruce Peterjohn, chief of the U.S. Bird Banding Laboratory at the USGS Patuxent Wildlife Research Center in Maryland. "She lays her eggs and raises her chicks. Common sense says at some point she would become too old for this."
Wisdom is a Laysan albatross, one of 22 albatross species -- and one of the 19 that are threatened.
Many albatross species neared extinction in previous decades as commercial driftnet fishery killed hundreds of thousands of birds. In recent years, stronger regulations and safer fishing practices have helped albatross populations stabilize.
"In the face of dramatic seabird population decreases worldwide -- 70 percent drop since the 1950's when Wisdom was first banded -- Wisdom has become a symbol of hope and inspiration," said Dan Clark, manager of the refuge.