Grunion Runs at Bolsa Chica

On spring and summer nights, California grunion swim up onto sandy Southern California beaches, including Bolsa Chica, to lay their eggs in the wet sand. California State Parks says grunion runs at Bolsa Chica come at the new and full moons, and its grunion programs return in March 2027. Under state fishing rules, catching grunion is closed April through June, and the rest of the season you need a license and may use your hands only.

What a Grunion Run Is

The California grunion is a small silver fish of the silverside family, usually 5 to 6 inches long. Its spawning is unique, according to the California Department of Fish and Wildlife (CDFW): grunion leave the water at night to spawn on the beach. For four nights in a row, starting on the nights of the full and new moons, spawning begins after high tide and goes on for several hours.

As each wave breaks, grunion ride as far up the sand as they can. The female digs into the wet sand with her tail until she is half buried and lays her eggs; males curl around her to fertilize them, then everyone heads back with the next wave. A single spawn takes about 30 seconds. The eggs incubate in the sand and hatch about 10 days later, when the next high tides wash them out.

When to Go

• Season: CDFW says spawning runs from March through August, sometimes in February and September.
• Peak: late March to early June.
• Nights: the four nights starting with each full moon and each new moon, after the high tide.

California State Parks' Bolsa Chica page says that at new and full moons in summer, visitors can enjoy grunion fishing by hand. The park's own Grunion Run public programs are listed as returning in March 2027; watch the Visitor Center and the State Parks events page for dates.

CDFW does not recommend any single beach, because safety conditions and local curfews change. Its advice: call the state or county beach lifeguards, who can often tell you whether a recent run happened.

Keep the park hours in mind. Bolsa Chica's beach closes at 10 p.m. and car gates close at 9 p.m. (hours), and CDFW's 2026 forecast run times (given for the Los Angeles Harbor area) mostly began after 9:30 p.m., so many runs fall after this beach closes.

The Rules for Catching Grunion

From CDFW:

• Closed season: April through June (extended in 2022). Touching or catching grunion is not allowed then; quiet watching is allowed.
• Open season: a fishing license is required for anyone 16 or older.
• Hands only. No nets or tools, and no digging holes in the beach to trap them.
• Limit: 30 grunion per day, which is also the possession limit.

The State Parks Bolsa Chica page likewise says grunion may be caught by hand under state law with a fishing permit.

Watch, Don't Take

CDFW encourages people to watch rather than catch. If you see a female laying eggs tail-first in the sand, leave her and the eggs alone so the run can finish. Females do not die after spawning; they can spawn several times in a single four-night event and in several events each year.

Good For / Maybe Skip If

Good for: a spring or summer night out with kids, a free nature show at the water's edge, and anyone curious about Southern California's odd fish.

Maybe skip if: you want a sure thing. Runs are not guaranteed on any one beach or night. On an off night, a fire ring is a good fallback.