This images shows off the colour of the swallow very well, which is structural colour not blue pigment. The BG is very nice. For my taste, more space to the right and less at the top would work better. A lower head angle, more toward the photographer would have worked better as well. Focus point does not include the head and eye so a bit soft there. I see some noise in the darker areas suggesting underexposure followed by too vigorous brightening.
Sid
Both critiques are on the money. Make sure to check your histogram and set it so that you get those highlight alerts to prevent "blowing out the whites". Waiting for the head to turn will give you a better pose and put the head in the plane of focus. There's a lot to think of when you photograph but the great thing about digital is that it's easy to keep practicing and learning. Hopefully you will be able to work on them again....and it's always rewarding to see it all come togehter.