Common tern are quite, well, common around the nature reserve and I around an hour watching this individual hunting. The bird was hovering over different parts of the lake until it found a target, and then plummeted really very quickly down on to its prey.
Capturing a bird in flight is not easy… and it was an overcast day so I had to battle between boosting ISO (introducing noise and reducing the tonal range and fine detail) and opening the aperture (f7.1 is acceptably sharp on my big 500 mm lens, but f8 is much better. Any faster than that and the detail becomes a little softer) so capturing the fine detail was a challenge. That said, the fact that the tern was hovering did make life easier.
Black and white was the obvious choice given the colour of the bird and the monochrome overcast cloud background. The fine detail of the wing and tail feathers really make this image for me. I chose the square crop instead of the more traditional rectangular is that with the positioning of the wings and the downward view of the head, there is no real directional weight to this image, so placing according to the rule of thirds or golden ratio etc. wouldn’t add anything.