At this location Night-Herons often feed during the day, even in bright sun.
The image was captured just as it caught the fish with head and neck fully extended and immersed. It seems that they keep their eyes open when striking and they curve their neck and body during the strike to allow for refraction. In addition the wings are opened sufficiently to maintain balance.
1D Mk IV, 800mm f5.6
1/2000, f11, ISO: 640, No flash.