Posts Tagged ‘sub-adult’

When Bald Eagles (Haliaeetus leucocephalus) are born, they have brown heads, brown eyes, and a black beak. It takes about five years for them to develop the characteristic white head, pale eyes, and yellow beak that we associate with adult bald eagles. Certain changes take place each year and it is possible to estimate the age of immature bald eagle on the basis of its appearance.

I believe that the eagle depicted in the two two photos is about 3 1/2 years old. There is still a good deal of mottling in the feathers on its chest and some brown patches on its mostly white head. If you would like more detailed information about the developmental stages of bald eagles, I highly recommend an article by Avian Report entitled “Juvenile & Immature Bald Eagles.”

I do not see eagles of this age very often at Occoquan Bay National Wildlife Refuge, where I took these photos last week. Most of the eagles that I see are adults or are a year or two younger than this one. From what I have read, eagles reach mating age at about the same time that they get their white heads and tails, so I doubt that this eagle has already found a mate—in human terms, I guess the eagle might be characterized as a teenager.

Bald Eagle

Bald Eagle

© Michael Q. Powell. All rights reserved.


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