my
bredli is the same way. She is 11 months old and seems to do it with still objects. mind you when she is sitting on my hand, she will strike at every moving object when she is hungry!
I am trying to handle her as often as I can to try and settle her down a bit. As for snakes eyesight I cant offer any advice. I know they use the fork in their tongue to determine direction of prey, but really I have a lot to learn.