Hi Paul - you've captured the action here!! King sized worms over there!!
I like the side-lighting giving some modelling to the bird - a feature that is often lacking in many bird photographs.
A smaller aperature to get greater DOF on the subject would further enhance this image for me.
Great action and that worm makes it really funny, too. :) I would have gone to ISO 200 and f/8 for wider DOF. The whites look a bit overexposed on my monitor.