Like this image very much. Agree with Rachel (and yourself) that the water should be cleaned up. I would also prefer a crop that wasn't quite as square. Maybe a tad off the bottom and the top and adding a bit in front of the bird.
I agree that a more horizontal format would also work well here. I'd consider cropping from just above the breaking water in the FG of the image and chopping it off right there. An incredible pose, Ian...lovely light...great exposure...and the fish in his mouth tops it all off. I'm loving this one!
Great timing and pose. I always like egret shots that show water reflections on the white feathers. The shadowed side of the right wing looks a little noisy, and now that I see the noise I can't ignore it. I don't mind a square crop, although I think I would do it with the bird more to the upper left, less but equal space on top and left, more but equal space on bottom and right.