you can make a batch and do it that way. however no, you don't. unless you have to fight it out in court, having it registered early is a good idea. but you still have to pay money in court, and it's doubtful that it's worth it in the end. the images are yours as soon as you start.
unless i had to go to court, i would copyright it officially then. but even if you don't, you can still win, you wouldn't get as much as if you did register.
---Mike Savad