Another from the ICF Pro-tour last spring.. Here I was photogaphing another bird in the portrait comp when this bird flew in.. I just aimed and fired away as it went by. I didn't have time to turn the lens horizontal. Most of the images had cropped wings, tails etc. Got lucky here.
Full frame
Camera Model: Canon EOS-1D Mark IV
Shutter speed: 1/4000 sec
Aperture: 4
Exposure mode: Manual
Metering mode: Multi-segment
ISO: 500
Focal length: 500mm
Agree with Mikko on the flight pose - very dramatic. I'm impressed that you got so much of the bird (including the wing tips) in focus at f/4. The BG is nicely OOF and the image overall has excellent sharpness and exposure. I might darken the tail feathers a bit where they emerge from the bird's body.
I would have made this a horizontal crop, with room on the left for the bird to fly into. But I can also understand how you saw this as a vertical crop considering the position of the wings.