Sunday, October 3, 2010

Do Birds Go Grey or White Feathered in Old Age?

I'm watching the dozens of finches attacking my  new mesh finch feeder and see one with a white crown of feathers. I'm wondering if old birds go grey? Sarah - Lansing, MI

That's a great question! Unfortunately most wild birds don't survive long enough to reach old age. 

In the photos you sent me, the goldfinch looks like it has leucism, a condition characterized by reduced pigmentation in animals.

Right now scientist describe two kinds of Leucistic birds, pale and pied. Pale leucistic birds will have the same markings, but are extremely pale. Pied Leucistic birds, like the one in your photos, have patches of white. Leucistic birds are relatively unusual but much more common than albino birds which are completely white with pink eyes, legs and bill.

The terms leucistic and leucism are derived from medical terminology. The prefix leuc- is the Latin variant of leuk- from the Greek leukos meaning "white". The correct pronunciation of leucistic is ( loo-kiss-tic) and leucism is (loo-kism) since the prefix in Greek and Latin are pronounced with the hard C or K sound.

Thanks for sharing.

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