My wife’s ability to spot eagles is uncanny. It’s like a 6th sense, seriously. It’s like the moment an eagle enters her periphery, she knows and can point straight to it. Last week on a hike, she did it again, but this time she wasn’t quite sure what to call it. Honestly, neither was I. See, I’d consider myself a pretty good birder and I very rarely need to consult a field guide. However, I flip-flopped repeatedly on my id of this bird for quite awhile before settling on my answer. Why was it so difficult? The raptor we were looking at was slightly back lit, perched on a dead branch in a tamarack bog. It was large, clearly an eagle, with dark brown feathers that appeared slightly auburn in the sun. It head a partially yellow beak with a dark tip and yellow legs. Clearly, we were looking at a Golden Eagle…or was it a young, immature Bald Eagle? Here’s a couple pictures.
If you ever find yourself in the midst of the same debate, here are some tips to help you get the right ID:
This should have been my first check, and is likely the most useful tool in immediately differentiating between any two similar looking species.
On the left is the range of the Bald Eagle according to the Cornell Lab of Ornithology’s All About Birds. On the right is the range of the Golden Eagle according to the same source. Now, these maps aren’t always the most easy to interpret for those who may be unfamiliar with birds, so here’s a brief explanation. The red “breeding” areas are places in which the species can be found during the summer. the blue “nonbreeding” areas are places in which the species can be found during the winter. The yellow areas symbolize places the birds may be sighted in their travelling between those summer and winter areas.
So for our July sighting in North Central Minnesota, we can use these maps to make some deductions. According to the maps, Bald Eagles are present in the area during the summer while Golden Eagles would only be present during the winter or during their migration. Since July is mid-summer—definitely not a migration time—it can be assumed that what we saw was an immature Bald Eagle.
But what if you live in an area where their ranges overlap? Here are a few more differences you can use to tell them apart.
Feather Coloration and Patterns
The Golden Eagle’s (above right) legs are covered almost entirely in feathers whereas Immature Bald Eagles (above left) have bare lower legs. Most likely, catching a glimpse of leg isn’t always going to be the easiest thing to do, so the next best way is to witness them in flight. While soaring, Immature Bald Eagles (below right) reveal white patches—best described as mottled—around their body and at the ends of their largest wing feathers, called primaries. Their tail is often mostly white with a dark brown trim. As seen while in flight, Golden Eagles (below left) have smaller heads with solid brown inner wings. When you can get a glimpse of the back of the head, called the nape, the Golden Eagle reveals a golden brown mullet.
Golden Eagles tend to prefer open habitat at higher elevations such as cliffs and mountains, though they use a wide variety of habitats. After all, they are the most widely distributed eagle in North America. They may be found in grasslands, desert, tundra, forest, agricultural land and along some waterways.
Bald Eagles tend to prefer areas closest to water due to their affinity for fish as a food source. They’re most commonly seen along lakes, perched over rivers, in wetlands, or along coastlines.
Golden Eagles are often seen alone or in pairs and fly with their wings in a slight “V”, like a Turkey Vulture—though not nearly as drastic.
Bald Eagles may be sighted alone, but it isn’t uncommon to see several of them perched near each other over a waterway. In some areas such as Alaska and near fish processing centers, it’s possible to see dozens and dozens of them at once. Bald Eagles fly with their wings straight out and rigid.
Next time you see an eagle and are unsure of which on you’re looking at, remember: Place, Color, and Behavior. If you’re still unsure, consult a field guide or an app like Merlin Bird ID from the Cornell Lab of Ornithology.
Buehler, D. A. (2000). Bald Eagle (Haliaeetus leucocephalus), version 2.0. In The Birds of North America (A. F. Poole and F. B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.506
Kochert, M. N., K. Steenhof, C. L. McIntyre, and E. H. Craig (2002). Golden Eagle (Aquila chrysaetos), version 2.0. In The Birds of North America (A. F. Poole and F. B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.684
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