Snow underneath eagles wings is such a great fill light. Very nice capture. Gorgeous!
Eagles like to ride ice floes floating downriver on the Mississippi River, near Davenport Iowa during the late February-early March ice break up, which gives similar reflected fill light beneath their wings. It is fun just to sit and watch them ride by, and then fly back up river to do it again.
I think this is one of best photographs i have ever seen. Amazing!