It's a great pose (in both images), but if you zoom in to 100% you will easily see that both are very noisy and poorly focused.
The focus isn't good, and the image could be brightened up a bit. But due to the focus issues, I'm afraid this isn't useful for stock.
Noise and blur, high iso. Taking a shot of this type is very difficult, something went wrong at the time of the shot, you had the focus but, either you shot handheld or you pressed the shutter too much, you did not use a remote release, you had a 600mm with that focal length, you have to be very stable do not move the camera a hair, apart from putting the camera in motion focus and continuous shooting, notice that the splash of water is more focused than the bird, it means that when you pressed the shutter the bird had already gone out of focus Comosicion doesn't help either, you should frame it better,
It's just my opinion, which could be very wrong
Thank you very much for your analysis and suggestion. I just start to photo birds and like to handheld and now I know I need to change. Thank you again!