The California grunion (Leuresthes tenuis) is a small slender fish with a bluish green back and silvery sides and bellies. Grunion, close relatives of topsmelt and jacksmelt, range between five and six inches when they are fully grown. A truly unique characteristic of grunion is that they come completely out of the water to spawn. Each year during the spring and summer months three to four nights after the full and new moon grunion will completely leave the ocean to spawn. Females will burrow a nest in the sand, while males fertilize the deposited eggs. Their journey out of the water is so predictable that their arrival on the beaches can be calculated almost a year in advance.