Rainbowfishes and Silversides: Atheriniformes

Physical characteristics: California grunion grow to 7½ inches (19 centimeters). They are long silversides with a prominent silvery band on the sides and bluish green on the back.

Geographic range: Grunion live on the coast of North America from Monterey Bay, California, in the United States to the southern part of the Baja Peninsula in Mexico.

Habitat: California grunion live in coastal ocean waters.

Diet: California grunion eat animal plankton.

Behavior and reproduction: California grunion are known for their spawning behavior. They emerge from the surf in large groups to spawn on beaches during the highest tides of the spring and summer California grunion are known for their spawning behavior. They emerge from the surf in large groups to spawn on beaches during the highest tides of the spring and summer months. (Illustration by Patricia Ferrer. Reproduced by permission.) months. Both males and females ride in on waves and are left exposed on the sand when the water recedes. Females burrow tail first into the sand to deposit their eggs, and males place sperm on the eggs as they are released. The eggs are left buried in the sand a few inches below the surface and hatch in about two weeks, when they are agitated by another high tide. After spawning, adults return to the sea. They can spawn numerous times.

California grunion and people: California grunion are collected by hand during spawning runs.

Conservation status: California grunion are not threatened or endangered. ∎