[quote=@Haeo]
but I was only aware of one kind of hawk in Skyrim...
[/quote]

That's just in game. And there's variation even in the same kind.

Anyways, what Schaft said. Or we could RNG, I'll roll a 15 sided die and the number is what you get.

[img]http://s2.postimg.org/jm7iwrhzd/feathers.png[/img]

Zoom:

[img]http://s11.postimg.org/xuc0a05eb/feathers.png[/img]