California Grunion

Leuresthes tenuis





The California grunion, sometimes called the “fish that spawns on land”, are a well studied fish due to its unique spawning behavior (1). These fish are greenish above their silver-blue lateral stripe and silvery below (1). Spawning occurs between late February to early September with peak spawning occurring between April and May (1). Spawning events, also called grunion runs, are based on tidal cycles with runs beginning immediately after high tide (1). Grunions beach themselves and females burrow their eggs 50 to 75 mm below the surface of the sand while males discharge their semen into the sand (1). Eggs reman buried until the next high tide series during which eggs become agitated by the surf (1)(2). Grunions fed on copepods and protozoans, and are common prey for a number of predators (1).  


(1) Fritzsche, R.A. , R. H. Chamberlain, and R. A. Fisher. 1985. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (Pacific Southwest) -- California grunion. U. S. Fish Wildl. Serv. Biol. Rep. 82(11.28) U.S. Army Corps of Engineers, TR EL-82-4. 12 pp.

(2) Martin, K. (2006). Introduction to Grunion Biology [Scholarly project].

(Photograph) (c) Casey H. Richart, some rights reserved  (CC BY-NC)

(Photograph) (c) Ana Lutz, some rights reserved  (CC BY-NC)


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