Grunion runs are a unique natural event where small, silvery fish come ashore to spawn on sandy beaches along the California coast. This spectacle offers a rare opportunity to observe marine life’s distinct reproductive behavior. The predictability of these events, tied to tidal and lunar cycles, allows for planning to witness this phenomenon.
Grunion Run Essentials
California grunion (Leuresthes tenuis) are small, silvery fish found only along the coast of Southern California and northern Baja California. They are known for their unusual mating ritual, coming completely out of the water to lay eggs in the wet sand. Females bury their tails to deposit eggs, which males then fertilize by wrapping around them.
Grunion runs occur from March through August, with peak spawning from late March to early June. They are closely linked to the highest tides following full and new moons, usually taking place two to four nights after these lunar phases. Fish typically appear on the beach a few hours after high tide, often between 9 PM and 1 AM, and a run can last one to three hours.
Regulations protect the grunion population. A California fishing license is required for individuals 16 or older who intend to catch grunion. Grunion may only be taken by hand; nets, tools, or digging are prohibited. A closed season, typically April 1 through June 30, prohibits taking grunion, though observation is permitted. During the open season, a daily limit of 30 grunion per person applies.
Prime Beaches for Grunion Viewing
Many Southern California beaches offer suitable conditions for observing grunion runs, featuring expansive, gently sloping sandy shores and minimal light pollution. While the California Department of Fish and Wildlife does not officially recommend specific beaches, several locations are known for consistent grunion activity. Grunion prefer darker, quieter areas, often at the outer edges of shorelines, away from brightly lit sections.
Cabrillo Beach in San Pedro, Los Angeles County, is a popular spot, often hosting educational events. Its protected inner harbor and accessibility make it a frequent public viewing location. North of Los Angeles, Leo Carrillo State Park in Malibu offers a natural setting with sandy beaches conducive to grunion spawning.
In Orange County, Doheny State Beach in Dana Point is recognized for its long sandy stretches, providing ample space for grunion. Bolsa Chica State Beach in Huntington Beach is another notable Orange County location known for grunion runs.
Further south in San Diego County, La Jolla Shores is a wide, sandy beach with a gentle slope, providing an ideal environment for grunion. Silver Strand State Beach in Coronado, south of San Diego, is also a highly regarded location, offering extensive sandy areas with minimal light pollution. Coronado Central Beach is another wide, flat beach in San Diego County where grunion runs occur.
Tips for a Successful Grunion Run Experience
Prepare for an evening beach excursion. Bringing a flashlight with a red filter is advisable, as white light can deter grunion from coming ashore. Warm clothing in layers is important, as beach temperatures can drop significantly at night, even during warmer months. Consider bringing chairs or blankets for comfortable waiting, along with snacks and drinks, as runs can occur late and last for a while.
Observing grunion ethically helps protect the species. Minimize light usage and avoid shining flashlights directly into the water, as this can scare the fish away. Quiet behavior and minimal movement are beneficial, as loud noises and sudden actions can disturb the grunion. Give the fish space and avoid disturbing them, especially females actively burying their eggs.
Manage expectations, as grunion runs are natural events and not always guaranteed. Popular locations can draw crowds, particularly during peak times. Be prepared for darkness, as beaches are often unlit at night. Safety is a consideration; be aware of tide changes and uneven terrain in the dark. Stay with your group and protect against cold conditions.