PESCADERO (KPIX) -- On the San Mateo coast, a historic lighthouse isn't the only thing casting a glow over the sea at Pigeon Point.
Philong Nguyen of San Jose stood on a cliff, escorting his Canadian cousin on a first visit to California.
"I just saw waves glowing, Nguyen remembered. "I wasn't sure of it. I thought it was just waves crashing over itself."
So Nguyen, a student at De Anza College, shot some long exposure photos and captured the blue glow more clearly than his eye could see.
"It was very, very amazing to see. I've been to Pigeon Point a lot and I have never seen that."
Marilou Seiff, executive director of the Marine Science Institute explained.
"The pictures show the bioluminescent dinoflagellate, Noctiluca, which occurs in coastal waters usually."
Seiff says the one-celled organism Noctiluca scintillans -- also known as sea sparkle -- is nontoxic to humans and is often seen here in the summer feeding off plankton. When the water is disturbed at night, by fish or wave movement, the Noctiluca lights up as a defense to scare away prey.
Seiff says you'll find the glowing organisms off coastal waters worldwide where plankton is plentiful.
Nguyen's cousin gave the phenomenon a glowing review.
"He told me this was his best California experience ever," Nguyen said.
As pretty as glowing waves are, some scientists are concerned that a growing number of algae blooms is a result of climate change and could disrupt the marine food chain.
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