I like the fish that the heron has caught.......interesting to see that angle of the fish. I think I would like the wings to either be in more of an up or more of a down position. You might try cropping this as a pano to draw more attention to the bird.
There is a strong contrast in this image. The Heron looks sharp and the fish is a nice plus. If you want Herons in flight, you need to come to Venice Rookery!! :)