I didn't catch the point for the first second. I thought there were multiple birds. There aren't many physical differences among the first three bird images. I wonder if there would be a way to blur the birds showing movement, maybe one into the other or slow enough so the wings blur to show movement. That way you would see the flight as a composite immediately and would understand this is a movie done in still form. Is there a way to do this so you bracket the shutter speeds so the last is sharp and the earlier ones blurred?
Nice shot.