Problem:
I recognize people around me by their facial appearance to begin with, then by their little idiosyncracies; this applies perhaps to most other humans too. We rely pretty heavily on vision - perhaps because we are a primarily diurnal species gifted with the ability to distinguish colour.
But then, so are birds of prey e.g. eagle, kite ...
Question: Do diurnal birds of prey identify each other by their appearance? Please give some suggestions.