While I like the ethereal feel to this one and what you were going for, I am afraid the image quality is suffering and some of the bird appears quite hot. This is where a flash may well have helped you reach your goal, but I would like to wait for someone with more experience in high key images to comment.
I like the comp and neat floating pose (especially the far wing) but I agree the IQ is not what it could be. I like high-key images but prefer them in overcast conditions. That was a tough situation you had here!