So, if it IS a double-exposure, then the two pics were taken one right after the other. That means that the deer was being stalked by the cat, only not as close behind as the picture shows. Pretty cool!

It makes sense too, because if it's not windy out, everything in the picture would stay the exact same, except for the two animals that walked by. The camera sure wouldn't be moving.

I'd like to get a closer look at the time-stamp, to see how far apart they were. I bet it was close tho, because the cat's in stalk-mode. I'd guess that deer wasn't more thana minute or two ahead of the cougar.