To discourage predation, the top row of rocks (there are several layers) are balanced upon the lower in such a way that they move if stepped on. I have let the water level drop to a point that it would have to be really determined, and then there's only one spot where I think it MIGHT be able to pull itself out; my intention is to remove those rocks, add some fill under the liner and raise that "wall". I have placed several large rocks on the edges of plant containers that start below the waterline for basking, and it seems to favor one above the others; I have seen it up there for 3 days now - from a distance, and if I walk slowly, with a staggered step as I come around to the pond area. If I walk "normally", all I get is the big "splash" as I'm coming round the corner
Today, I'm going to try to sneak around with my real camera, instead of the cell phone I usually post photos with, because I hoping the camera's Zoom will get a decent pic. If I do, and if I can figure out how to upload the pic, (I'm an old broad who is not very computer savvy), I'll post it.