Grunion Take Patience and Flashlights

The line of people surges forward and then recoils just like the waves rolling onto Cabrillo Beach.

“Stay back,” comes an order delivered by bullhorn. About 600 people crowding the shoreline edge back a few paces. “Turn off that flashlight.” A light goes out. “Try to remain quiet. We don’t want to spook the fish.”

Self-control doesn’t come easily to the excited throng--half of them children--hoping to catch a glimpse of one of Mother Nature’s most unusual shows: fish that ride the surf onto the beach, bury their eggs in the sand and then catch a wave back into the ocean.

It’s 10 on a Saturday night and the audience is eager for the main event to begin. They have, after all, spent hours at Los Angeles’ Cabrillo Marine Aquarium learning about the small silvery fish called grunion and their unique spawning habits.

They watched an old Technicolor film that showed the grunion’s nocturnal dance, the females burrowing into the sand tail-first, the males crowding around them eager to do their part.

They practiced the grunion dance, wriggling their bodies like the fish.

They tried their hand at hatching grunion eggs. Each was handed a baby-food jar with a pinch of sand laden with grunion eggs and some seawater.

Then, they were told to vigorously swirl the water in the jars to mimic ocean turbulence. That action coaxes baby grunion to burst from their eggs. In a blink, each egg was transformed from a diminutive pair of eyes inside a clear, round sac into tiny free-swimming fish.

“It’s like magic,” said Brian Navarro, 9, of Redondo Beach, holding the jar to the light. “But one can’t get out.” He frowned. “Now it did,” he said, brightening.

The crowd sat politely through a brief lecture on the grunion, a fish found only in Southern California and northern Baja.

“We hope to convince you that these rascals really exist,” aquarium staff member George Van Doren said in an auditorium squirming with children and their parents. “A lot of people say they have been grunion hunting for years and never seen them.”

Mating schedules are as imprinted in grunion as dates are on a calendar, so much so that grunion runs can be predicted up to a year in advance.

Grunion spawn from early March through early September, but only on the third or fourth night after the highest tides that are brought on by the full or new moon. More precisely, grunion tend to fling themselves on the beach one to three hours after high tide.

It’s all part of their ingenious adaptation. Waves tend to erode sand from the beach as the tide rises and then deposit sand as the tide falls. So the grunion eggs, which the female buries two to three inches into the sand, get covered with a fresh layer of sand until the next high tide--about 10 days later--when the eggs are ready to hatch and the newborns are ready to swim for their lives.

Marine biologists don’t really know if grunion populations are healthy or declining.

They are aware, however, that grunion have largely disappeared from some beaches in Los Angeles, Orange and San Diego counties that are raked regularly by tractors to remove trash and smelly seaweed. What’s amazing about grunion is that they continue to exist at all along one of the most heavily populated shorelines in the world.

Some biologists believe grunion are a cautious lot. They first send a male scout or two onto the beach to check things out before coming ashore en masse. If the scout doesn’t come back, they wait or move to another beach. Others think this is bunk.

Either way, pinpointing precisely when the grunion will run is less than an exact science.

“The most important thing to bring to a grunion hunt is patience,” said Larry Fukuhara, the Cabrillo Marine Aquarium’s director of public programs. He should know. He’s been leading grunion tours for 16 years.

For the first aquarium grunion program last month, 800 people showed up, but not a single grunion. On this night, 600 people have bundled themselves against the damp chill and headed out to the beach to witness a run. Some brought buckets to collect grunion for a fish fry back home. Most are out there just to watch.

A half-dozen night heron patrol the beach, the beat of the wings giving away their location on a night when moonlight is shrouded by coastal fog. The presence of the heron is a good sign, aquarium staff members say. The birds would not be here if the fish weren’t ready to run.

A couple of feral cats hang back in the shadows, hoping to make a quick meal of the 5- to 6-inch grunion flopping on the beach.

Minutes turn into hours as the energy drains from the once-excited crowd. Most people sit down. Some lie down. Others begin to drift away.

Around midnight, Fukuhara makes the call. Everyone can turn on their flashlight and take a look, before the aquarium staff usher all of the people from the beach.

A powerful beam of light sweeps across the water revealing an ocean churning with grunion--a dozen yards offshore.

Fukuhara is flummoxed. “I don’t know what happened,” he says. He’s proud of his percentages. His groups see grunion more than 90% of the time. “I seldom miss. I’ve missed twice in a row.”

The next night, a Sunday, only a couple of dozen people show up at Cabrillo Beach. There’s no aquarium-led tour. No bonfires. No boisterous, flashlight waving crowd. But the shore is teeming with grunion.

With each wave, the wet sand is carpeted with a squirming mass of silvery fish. A few people around frolic among the fish until a city Recreation and Parks ranger brusquely interrupts the fun. Everyone must leave immediately. The beach is closed.

“I like to come the second night,” said Rene Kilpatrick of Harbor City, packing up to leave with her son Travis. “There’s hardly anybody here. Just us and the grunion.”

For future run dates and grunion facts, go to “the Amazing Grunion” on Fish and Game’s Web site, www.dfg.ca.gov, or call the Cabrillo Marine Aquarium, (310) 548-7562.