San Francisco

Countless Jellyfish Wash Ashore at Pacifica Beach in San Francisco

The small, translucent, gelatinous blobs are harmless Moon Jellyfish that wash up to the beach with the current, according to Malilou Seiff of the Marine Science Institute

A countless amount of jellyfish washed ashore at Pacifica State Beach in San Francisco over the weekend, worrying some locals who were enjoying the long Memorial Day weekend on the sand.

"It freaks you out at first. I mean, your hands are hitting them when you’re paddling in the water. And you think, 'oh man this is going to sting,' but then you realize they don’t," said one surfer Josh Badura.

The small, translucent, gelatinous blobs are harmless Moon Jellyfish that wash up to the beach with the current, according to Malilou Seiff of the Marine Science Institute.

"Jellyfish are not swimmers. They float with the current. So when you get onshore currents, and onshore winds, they just float ashore," Seiff explained.

The Aurelia aurita, the scientific name of the Moon Jellyfish, is one of about 20 species of jellyfish off the coast of California, Seiff said.

Moon Jellyfish have a mild sting but they're generally harmless to swimmers. They're identifiable as a clear, flattened disk, with numerous small tentacles around the edge and a pink four-leaf clover design in the middle, according to the National Oceanic and Atmospheric Administration.

Tanya Schevitz was at Pacifica Beach on Monday and she said she, and her husband who's a surfer, had never seen anything like it. 

"Generally, it’s seals, whales, dolphins…and normally you don’t see, THIS," Schevitz said. "We were sitting on the beach hanging out, and my husband came up and told us, 'you gotta come down and see this.' And we ran down to the beach and there were just blobs of jellyfish everywhere.” 

The Pacifica State Beach said the public works department has been in touch with the California Department of Fish and Wildlife, but there are no plans to clean up the hundreds of mostly dead jellyfish. 

"It's a natural occurrence. It happens every five to ten years. They all come on the beach and all of the sudden, they're gone," according to a spokesperson for the Pacifica Parks, Beaches & Recreation Department.

In 2010, a similar phenomenon occurred at Ocean Beach with thousands of jellyfish stinking up the shore in San Francisco, SFGate reported.

While the jellyfish aren't necessarily dangerous, Seiff said she wouldn't recommend beachgoers to touch them as different people may have different reactions.

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