The California Grunion is a small, iridescent fish that shows a unique spawning behaviour when actually coming out of the water to lay its eggs in the moist sand on the beach.
Females use the highest spring tides to burrow themselves backwards into the sand while the males follow them to fertilise the eggs that are deposited 5cm below the surface. Around ten days later, when the tides next reach the same height up the beach, the eggs are disturbed by the surf and hatch, and the newly emerged grunions are then carried out to sea.