SENEY, MICH. -- The world’s two oldest documented common loons have returned to Michigan’s Upper Peninsula, where they have spent their summers together for 23 years.

According to a post on Seney Wildlife Refuge’s Facebook page, the long-term partners, a male known as “the ABJ” (Adult Banded Juvenile) and a female known as “Fe” (pronounced “Fay”) have made Seney National Wildlife Refuge in the Eastern Upper Peninsula their summer breeding grounds since 1997.

After wintering in a warmer climate likely somewhere in the southern U.S., the pair was spotted in the refuge this past weekend on a partially thawed pond called F Pool.

World's oldest loons return to Seney Over the weekend our friends Laura Wong and Larry McGahey biked into the refuge... Posted by Seney National Wildlife Refuge on Tuesday, April 14, 2020

The ABJ, banded as a young chick in 1987, will turn 33 this June, making him the oldest common loon of known age on Earth.

Fe, in contrast, is the oldest-known loon -- her exact age is unknown, but because she was banded in 1990 as a mother, and the youngest verified age of common loon reproduction is four, researchers know she will be turning at least 34 this season.

Fe has fledged 33 chicks from Seney since researchers first began tracking her, the post said.

The pair is two of many banded refuge loons that have been tracked for years. More information on the ABJ and his mate can be found on the Seney National Wildlife Refuge website.

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