He has it on the end of a snare on a stick. You can see the wire on the snare around the frog’s neck. It looks like it’s nearly two inches thick when compared to the man’s thumb. It’s a thick wire, but it’s not nearly that thick.
Also look at the arm behind the frog, especially in the photo at left. He’s holding the frog straight out so his arm would be foreshortened completely if photographed straight on, and the frog is positioned so it blocks the view of the arm and the stick. This makes it harder to judge perspective, because there’s nothing connecting the foreground to the background.
