Arrived at Millennium Park in West Roxbury at dawn. Listened to the meadows wake up. Sparrows chirping. Robins caroling. Blue herons barking. Two giant V's moved across the sky.
It's northern harrier time. Low flyer and low percher. Look at its amazing owlish face. [UPDATE one year later: Why did I think this was a northern harrier?] It was getting dive-bombed by a kestrel. Then it flew towards me (ever feel like a bird was going to fly right into your binoculars?) and landed in a tree right behind me.
Also, although the light wasn't good, I was pleased to find some white-crowned sparrows that actually had white crowns! Three of them, just sitting by the path, soon to be disturbed by some passing jogger or unleashed dog (or me).