How can you tell if a blue belly lizard is pregnant?

They generally will float in the water in stead of sink and if not in water then they won't move.

Or you can try this:

Poke his eye softly with a stick, finger, or something thin. I tried that with my turtle a few minutes ago because he wasn't moving. When I poked his eye with the tip of a mechanical pencil, he closed his eye and sunk his head further back into his shell.