Three things made photographing this cormorant difficult while it was in flight. First, cormorants are very black. Their feathers do not contain oil, so they do not reflect much light. Second, they fly very quickly. Third, the clear sky made shadows harsh. The only light on the bottom of the bird is light coming THROUGH its wing feathers. I photographed it with the 800 mm Nikkor at f5.6 (maximum aperture). I was able to stop the motion by using the aperture preferred mode with auto ISO which set the shutter speed to 1/8000th and ISO 800. Still, I had to reduce the contrast and boost the exposure when processing the image to get any detail in the shot. Without that, this shot of a cormorant landing was a pure black silhouette.