They lurk below the water then spring upwards into the air. They can either jump straight up and down, or sort of leap from side to side, although you need to watch where you place them or they can jump out of the water. If they do jump out of the water, they just sort of wriggle along the ground until they hit something, then they turn around and wiggle back, so you can have a fish jumping out of the water, wriggling along the ground and back then falling back into the water again.
Seems to work okay.
A couple of fish in action