Crows are smart... we have a couple that hang around our place and the Mrs pretends to throw food (but it's just what ever leaf she finds) at them.
They look at us as if we were morons

. (Loggy/Soggy no comment pls)
But I've noticed the crows were I am now don't make the same calls as where I was before.
The last place they made this baby crying noise... and 10km away they make a Juliar noise.
So I think they have local dialects.
Where as the Cockatoos seem to scream the same crap at you... but they look way cooler.
PS: I just bought some binoculars to observe birds

... Canon 12x36 IS II