Once upon a time, there was a crow. He was sitting by the sidewalk, minding his own business, when a photographer came along and annoyed him.
Wanting nothing more than a little peace, the crow flew up onto a nearby roof.
There was a jay already there who did not like the idea and called him any number of insulting names. She even flew off and scolded her mate into coming to help which, after a few minutes, he did.
The two took turns dive-bombing the crow, never quite touching him, but never really leaving him alone, either.
It was most annoying.