How is the life cycle of the grunion regulated by tides?

Grunion are the two species of genus Leuresthes. that are L. tenuis and L. sardinas. The species are found in the coasts of California. These species reproduce by external fertilization. The tides plays important role in reproduction of these species.

The females come on the sandy shores of the beach where they lay their eggs in the sand during high tides. The males wrap themselves around the females and secrete their sperms. The eggs remains hidden inside the sand for 10 days. With the next set of high tides, the eggs hatch and young grunions move towards the sea.