Reddit reviews The Crossley ID Guide: Raptors (The Crossley ID Guides)

I have to say that the Crossley ID Guide to Raptors is my absolute favorite and go-to Raptor ID Guide. It's better than a regular Peterson/Sibley/Audubon/etc in my opinion because it shows how the raptors look at different stages, from different angles, and from different altitudes.

If you have a smartphone, I also personally recommend getting a bird app. The Audubon Guide to Birds is free, and has a great little search tool where you can plug in the information about the bird you saw, and it will narrow down for you what it could be. A lot of people here like the Merlin app as well, and it does the same thing.

I would say that the first step to learning to ID raptors is first, learn to differentiate between all birds of prey in your area. In the US, in general from smallest to largest (this is a massive generalization; don't get on my case about it), we have falcons, kites, harriers, owls, hawks, vultures, osprey, and eagles. There are also caracaras which are technically falcons as well.

Once you have learned how to tell the difference between a falcon and a hawk, and a hawk and an eagle, etc, then start learning the specific species in your area, and what their field marks are. For example, the best field marking for a Red-Tailed Hawk isn't actually the red tail, but the belly band, since RTHAs don't get their red tail until they're between 2-3, and you often can't see the tail color from the ground, but you can see their belly band.

Behavior is also important. Once you learn the raptors in your area, you can start learning each species' individual behaviors and habitats. This can help you differentiate birds that are far away - for example, you can tell a vulture from an eagle because the vultures flap less often and circle on updrafts, while eagles generally don't do that. Bald eagles generally live around large bodies of water because they're piscivores. They also don't get their white head and tail until they're around 5 years old, which is why many people confuse them for golden eagles, and even hawks and vultures.

I'm sure everyone on this sub would be more than happy to help you learn! We're all bird nerds here who want to share the love of birds and the hobby of watching them! Feel free to ask questions!