I just wanted to chime in that in my experience with yellow bellied racers they are very difficult to switch to mice. In my area adults will pound amphibs but rarely take to mice in captivity. As Wayne mentioned I would stay away from the insects although I have witnessed on a few occasions them going for grasshoppers and large mormon crickets, so it is not that they can't eat insects, it is more that there are better options for them.

-Thomas