Over the past week or so I have been photographing quite a few wintering Bald Eagles of various ages, from one year old to adults, and I decided to write about the different growth stages seen in their plumage. Bald Eagles take about 5.5 years to mature to the typical white head and tail and solidly dark chocolate brown body, legs and wing feathers of an adult.
The bald eagle above is one year old and is a dark brown over all, the chest and back are a bit lighter. The eyes are a dark brown and the bill is dark with some yellow. A one year old eagle will show some white on the underside of the wings in the axillaries and coverts.
The circumstances when I photographed this eagle were pretty remarkable and I hope to do a post on it later.
A two year old bald eagle has some white mottling on the chest, there is more yellow developing on the bill and the underside of the wings show extensive white feathers. The top of the head is a more golden brown than a one year old eagle exhibits and the eyes are a lighter shade of brown.
I’ve heard that a lot of bird photographers prefer to photograph only adults bald eagles because of their well known plumage but I find that I enjoy photographing all of the various plumage’s because they are; after all, the various cycles of an eagle’s life.
A three year old bald eagle has some white on the chest, the underside of the wings are developing more dark brown feathers. The top of the head is lighter than a three year old’s is and there is some white developing under the chin and on the neck. They have a dark eye stripe and the eyes are paler. The bill will show more yellow and the darkness at the tip is growing lighter.
I’ve found bald eagles to be a challenge to expose correctly at all ages, when young you need enough exposure to bring out the details in the dark feathers. As adults though you also have to be concerned about the high contrasts of darks and whites and not blowing out the whites.
The four year old bald eagle above looks more like an adult, the head is nearly white with some paler brown feathers intermingling with the white. The eyes are much paler than they are when they are just yearlings. By now the bill is a solid yellow and does not show the dark tip at all of the younger stages. The tails show more white above and below. The body and wing feathers are nearly all dark including the under side of the wings.
Adult bald eagles have solid white tails plus the head and neck are also white. The eyes are very pale, almost white and the bill is a solid yellow and a bit brighter than a four year old bald eagle. The plumage of the chest, back and wings are now varying shades of dark brown.
Today the one year old bald eagle flew only 10 to 12 feet over my head and I can verify that their 80 inch wingspan is very impressive.
I’m fortunate to live in an area where the bald eagles winter over in large numbers so I can see and photograph eagles of all ages and all plumage growth stages. It’s great.
So, there you have it, a simple guide to aging Bald Eagles by their plumage development, legs and their bills with images showing the age progression. More precise aging can certainly be done by molt of the primaries and remiges but this is intended to be a simple guide.