- Beautiful golden eagle
- Golden eagle close-up
- Golden eagle looks wary
- Golden eagle looks around
- Nictitating membranes
- Plumage close up
- Talon close up
- Fly away
Golden eagles get their name from the golden or tawny wash of feathers on their head and neck feathers. Adult American gold eagles are otherwise dark (or chocolate) brown in plumage, with 'marbled' flight feathers on their wing and tail. They range from 26 to 40 inches in length. Overall size is a complicated issue - while American gold eagles tend to be smaller than their counterparts in Eurasia, the largest gold eagle ever recorded was a female banded and released in Wyoming in 2006. Although bald eagles are a little bit longer on average than golden eagles (34 inches in length versus 33 inches in length), the difference is small enough that some golden eagles will be longer than some bald eagles. Confusing the issue even further, golden eagles (unlike bald eagles) don't appear to follow Bergmann's rule: one study found that golden eagles in Idaho were larger than those from Alaska. We can confidently say that they have a larger wingspan than bald eagles: North American golden eagle wingspans range from 6 feet to 7.2 feet according to Animal Diversity Web.
|The eagle's nictitating membrane protects its eye|
Check those legs and talons out! Unlike bald eagles, adult golden eagles are 'booted' - that is, their feathers cover their entire legs down to the toes. This may help protect their legs from bites and scratches inflicted by struggling prey. Golden eagles eat more kinds of prey than I can list here, since over 400 vertebrate species have been recorded as golden eagle prey. Although golden eagles appear to have food preferences, they are highly opportunistic hunters that will predate most reasonably-sized animals. They aren't going to wait for rabbits if ground squirrels are available!
|Talons. 'He clasps the crag with crooked hands...'|
With their short, wide tails and long, broad wings, golden eagles are built to soar. They cock their wings in a slight 'V', somewhat like turkey vultures, and hold their wing tips wide open, flapping only when necessary. Unsurprisingly, they prefer open country and like to nest up high. Jumping off something high to attain lift is much less work than dead-lifting from the ground and height may, in some cases, make it easier to get prey to the nest. At Eaglecrest, the resident golden eagles nest in a large tree. Their large stick nest (smaller than a bald eagle's nest, on average, but still pretty large) is lined with grass and other soft vegetation when in use.
|The flash of white indicates an immature eagle|
Things that helped me write about this topic:
- Animal Diversity Web - Golden Eagles: http://animaldiversity.ummz.umich.edu/accounts/Aquila_chrysaetos/
- Wikipedia - Golden Eagles: http://en.wikipedia.org/wiki/Golden_Eagle
- Pawnation - Golden Eagles: http://animals.pawnation.com/interesting-golden-eagle-1588.html
- Nature - Eagles: http://www.pbs.org/wnet/nature/episodes/eagles/introduction/3089/
- Identifying feathers: https://www.fws.gov/lab/pdfs/trail.2003c.pdf
- How to age golden eagles. Worth the read - not an easy thing to do: https://www.aba.org/birding/v36n3p278.pdf
- Nictitating membrane. I love this blog: http://www.wqed.org/birdblog/2010/03/05/anatomy-nictitating-membrane/
- The golden eagle and philopatry