@alice@taedryn They also adore peanuts, and if you refill a plate at a regular time they will anticipate it and come greet you. And also give you shit if you're late, as I learned.
I second the peanut recommendation. I don't know about crows, but feeding ducks bread is mildly bad for them (iirc they get gastric problems from too much bread and they are very willing to eat too much of it).