She has hatched a chick on Midway Atoll National Wildlife Refuge for the sixth consecutive year. How do we know her age? She was first banded in 1956, when she was incubating an egg in the same area of the refuge. She was at least five years old at the time.
Bird banding is a way to use individual identification to study dispersal and migration, behavior and social structure, life-span and survival rate, reproductive success and population growth. You can use the Bird Banding Lab's website to look up the oldest known wild birds from banding records, among other things.