Hi Giuliano, I realise it's virtually impossible, but this shot would really rock if the heron would've been in full focus; then it would add the finishing touch. The colours and the tranquility of the landscape would've been excellent without the bird, too, though. Maybe even more so. I like the feel of this shot.
Nice still water effect...too bad it is considerably out of focus. Were you panning to shoot the bird?
This is a super tough scene - where you have low light that requires a slower shutter, and then the moving bird requires a fast shutter, and panning the camera to capture the bird.
I had moderate sucess with a similiar scene, I believe I shoot at 1/40th, f/5.6, ISO-100, 63mm focal length, on tripod.