I like the alert pose and the reflection, Mark, but my first thought is that the image is not sharp - perhaps a result of the low shutter speed? I would suggest a crop from the bottom for more of a pano look. Also, the brightness of the water tends to draw my eye so less of it would be better, IMO.
I do like the comp (wish for a slight head turn toward us) but agree with Steve on the sharpness and less water. I also like the way the reflection and tail touch.