Grunion Grunion Grunion are two fish species of the genus Leuresthes: the California grunion, "L. tenuis", and the Gulf grunion, "L. sardinas". They are sardine-sized teleost fishes of the New World silverside family Atherinopsidae, found only off the coast of California, USA, and Baja California, Mexico, where the species are found on both the Pacific Ocean and Gulf of California coasts. Many people enjoy catching grunion at events called "grunion runs." Grunion are known for their unusual mating ritual wherein at very high tides, the females come up on to sandy beaches where they dig their tails into the sand to
Grunion research points to a restricted resource that is adequately maintained at current harvest rates under existing regulations. In the 1920s, recreational fishing of grunion caused definite signs of depletion resulting in a regulation passed in 1927 that established a closed season of three months from April until June. Grunion stocks improved and in 1947 the closed season was shortened to the months of April and May. This closure is still in effect to protect grunion during their peak spawning period. The periodic appearance of the grunion on Southern California beaches, and the act of catching them, is locally known as