Last year, after years and years of hearing about the grunion run, we decided to head out to Cabrillo Beach to see what all the fuss was about.
First, let's start by defining grunion. In layman terms, grunion is a type of fish. "Grunion are known for their very unusual mating ritual. At very high tides, the females come up on sandy beaches and dig their tails into the sand to lay their eggs. A male then wraps himself around the female to deposit his sperm. For the next ten days the grunion eggs remain hidden in the sand, but at the next set of high tides the eggs hatch and the young grunion are washed out to sea (wikipedia.org)."
Yes, I know it sounds weird, but it is quite interesting to witness. The "grunion runs" happen late in the evening, about 10, 11pm, during the summer. There are hundreds and hundreds of people on shore waiting for the arrival of the grunion. Many people bring buckets to catch grunion (...and eat them??).
Volunteers ask the crowd to keep their distance and to avoid flash photography while everyone awaits the arrival of the grunion. As soon as the grunion arrive, the crowds can see the silvery fish flopping on the shore. Then the volunteers move out of the way and people start rushing towards the water (some to observe and others to "fish"). It can get pretty chaotic (if you bring young children, please be careful), but it is definitely worth experiencing at least once.
We didn't stay long, an hour or so was enough for us. Most of our time was spent waiting for the grunion. Please be aware that sometimes the grunion are a no show, so don't be disappointed if this is the case. Be sure to bring some blankets and some snacks!
For more info, visit: http://www.dfg.ca.gov/marine/gruschd.asp#runs