This insect was still alive. I believe the Bluebird was waiting for it to stop kicking. The predator is a wild bird. I shot this image at 550mm focal length. It is very enlarged. I did what I could to keep the grain to a minimum.
I am thinking this may be a Wood Cockroach, possibly a nymph or a female, as it resembles Parcoblatta sp.:
Click to see larger image of this male Bluebird and this prey item on my Flickr page: