I took a similar photo of a common tern last year shaking itself down and when I showed it to a lot of people they couldn't work it out at first as it looked as if the bird was flying upside down. Looks like you have captured this in some nice low sunlight which has lit the tern and the spray up beautifully. Very good exposure and detail and I really like the action you have captured. As with previous comments I think some additional space above the top wing would benefit the composition.
what a pose captured! and those droplets! pin sharp as well. wing close to the edge has been noted. nothing you can do about it when the action happens so fast and try to track it in the viewfinder...:)