14 February 2024
SAN DIEGO (FOX 5/KUSI) — Late-night beachgoers in San Diego have gotten a glimpse of bioluminescent waves crashing on the coast the past several nights.
Although it’s not something you see every day, Southern California is no stranger to the unique phenomenon. In early January, sightings of bioluminescence were frequent enough in the Los Angeles area that wave-watching tours started offering night cruises.
In San Diego in November 2023, photographer Vishwas Lokesh captured bioluminescent waves at La Jolla Shores and Torrey Pines State Beach.
Back in September 2023, a lucky few aboard a whale-watching cruise caught a glimpse of dolphins swimming through neon waters.
Bioluminescence at Torrey Pines Beach. (Photo: Mark Girardeau)
It may look out of this world, but what is it caused by? The blue light that can be seen is caused by the chemical reactions of bioluminescent organisms that live in the ocean. NOAA says many animals — like bacteria, sharks, squid, jellyfish, crustaceans and algae — have some bioluminescent family members.
Typically, the blue color is caused by bioluminescent dinoflagellates, a type of plankton that can cause the surface of the ocean to glow at night.
Ever seen a firefly? That’s a form of bioluminescence, just on land.
Mark Girardeau, along with a friend, captured these photos and videos of bioluminescence at Torrey Pines Beach and Ponto Beach in San Diego County Monday night.
A red tide is a “bloom” of phytoplankton, according to the California Sea Grant. A “bloom” happens when a group of phytoplankton, in this case dinoflagellates, begins reproducing rapidly. A red tide is visible during the day and creates a blue glow when churned up at night.
Girardeau said the glowing blue waves have been visible for the past few nights and that they seem to be getting more vibrant, which means they could be around for a little while longer for anyone wanting to see them.
Red tides can happen anywhere in the world, but in California it’s most frequently seen between Santa Barbara and San Diego. California Sea Grant says they are most common between February and September.
Red tides can stick around for days, and sometimes even months, depending on several variables, and favor warmer and calmer waters.