The bird was seen on top of a big tree, on the side of the river Tocantins, in the state of Tocantins, Brazil in January.
It looked like a bird of pray. It was about the size of a crow. The head was white with a black cap, with larger feathers in the nape. The chest was light colored with black spots. The tail was long and striped under. The bill was yellow, short and thick, and I didn't see the "bird of pray" hook (but it was far away). The wings were dark gray and the legs blue-gray. I only saw its front from below, I don't know what it looked like on the back.