Cute subject, good background. The breast looks slightly 'soft' leading me to wonder if the plane of best focus is just in front of the bird. Whatever the case, it is still a very attractive capture.
This is a killer behavior image and your details and colors are outstanding. I understand why you left the entire grass in the bottom of the frame. I would consider a crop off of the bottom including that grass b/c it would bring more focus into your gorgeous bird and its behavior.