Those Neon Blue Bioluminescent Waves Are Back In SoCal. Catch Them While You Can

Bioluminescent waves have been spotted in San Clemente in the last few nights, according to various accounts on social media sites.

These wondrous neon blue waves, which bear a passing resemblance to the color of the Blue Raspberry Slurpee at 7-Eleven, have enchanted Southern California beachgoers for many years.

What causes blue waves

Scientifically, the glowing blue waves are caused by a species of plankton called dinoflagellates, which swim in clusters causing a red tide, but when disturbed, they emit the glittering flashes of light.

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When they appear depends on conditions, which have notably gone through documented cycles over the last century.

During a spate of blue waves at the start of this year, David Caron, a professor of biological sciences at the University of Southern California, told us that bioluminescent waves are "documented in the literature as early as the early 1900s."

He added: "There were lots of these blooms in the 1970s, then they kind of disappeared for a while. They came back after that prevalent in maybe the early 2000s, and then they weren't that prevalent again, and now they seem to be back again.”

How to know when they arrive

As Drew Lucas, an associate professor at Scripps Institution of Oceanography at UC San Diego, told LAist before, the best way to find out about the these waves is to check social media.

Cue the popular Instagram account, Orange County Outdoors, which posted about the waves two days ago.

"Bioluminescence is back! Here’s some footage taken last night (4/18/24) on the south side of San Clemente Pier. It’s been visible two nights in a row now so hopefully it’ll still be lighting up these waves for a few more nights! There’s no way to accurately predict it but it’s worth checking it out," the post reads.

Sightings of the waves were confirmed on Saturday night by beachgoers on the Facebook page, Bioluminescence in Orange County/Southern California — with a couple users noting the occurrence happening on the south side of the pier at the San Clemente beach.

"We went last night around 9:30 to T Street beach in San Clemente and saw bits of bioluminescent waves," one user posted.

Tips for viewing

Back in January during another appearance of bioluminescence, we talked to Peter Nguyen, a resident of Costa Mesa, who keeps an eye out for new instances off Southern California's coast. He had these tips for others hoping to catch the phenomenon in person:

• Be patient 
• Go to a very dark place on the beach such as the shoreline so that your eyes acclimatized to seeing hints of light in the dark
• Plan to be there for over an hour because Nguyen says, “You're not going to see anything exciting, unless you're there for that amount of time, because some of the waves are very faint, and some of them you can't miss. And so, you want to be there for the ones you can't miss, and those happen 20-30 minute intervals.”
• Your feet will get wet, but Nguyen says the water is not as cold as the night air so dress accordingly