There is a claim that eagles can renew their lives by biting off their feathers, talons and beaks and then regrowing them, but this is not true. The myth states that when eagles reach the age of 30, their physical condition critically deteriorates. By plucking out their bad feathers and beak, they are supposedly able to live another 40 years. This myth stems partially from a metaphor in the Bible.
The variation of the lifespan of eagles is usually due to the species. For example, according to Learner.org, bald eagles are capable of living for up to 30 years the wild, but there are other breeds that live up to 70 years or more. Eagles in captivity tend to live the longest. This likely led to some of the misunderstandings people have about eagles. People see some eagles that live only 30 years and others that live several decades longer and think there must be a connection, even though they are just different breeds of eagles. There is a quote in the bible in Psalm 103:5 that says. “The youth is renewed like the eagle’s.” According to BibleStudyTools.com, this verse is likely purely metaphorical, but some people use the verse as evidence.