It is a little hard to get a decent photo of this, but... every Monday evening on our way home from swimming my son and I encounter the crows coming home to roost. There is a long stretch of straight road with huge power lines beside it which become completely full of hundreds, possibly thousands, of crows as the evening gets closer to night. It is incredible to watch them all flying in in unison and settling on the wires, then all taking off as a silly twit stops their car and gets out to take a photo of them. They then all fly back in in unison onto a slightly different part of the wires.
I have no idea who makes the call as to which section of the power lines they will land on for the night, but somehow they manage to get all the birds coordinated and settled for the night. All I can say is - I'm really glad it is not on the wires outside our house! The cleanup could become a little repetitive every day!