Photographer Captures Rare Glow Caused by Fireworms During a Ritual Near California’s Coast

In 1492, a day before Christopher Columbus made landfall in America, he came across a mysterious light that resembled “the flame of a small candle alternately raised and lowered,” as described by the American Museum of Natural History. The source of this light remained undetected until the 1930s, when some marine biologists figured out that it was emitted by mating fireworms. In July 2024, Patrick Coyne (@patrickc_la), photographer and videographer, witnessed a similar light swirling in the waters across Newport Beach.

Although the sighting is rare on a Southern California coastline, he revealed that the display of glowing lights was fireworms engaged in a mating ritual. Ever since the field of science evolved, scientists have remained curious about investigating the mating rituals of animals. Not just do they tell them about the physiological impulses of the species, but also the behavioral and psychological strategies they use for reproduction. For fireworms, one of the top conditions is warmth. They need warm waters and balmy skies to indulge in the process of fertilization.

Governed by a precise mathematics of rolling tides and moon cycles, these fireworms gather inside the oceans during the summer season. Once the dusk sets in, the tiny, half-inch-long females emerge from the seafloor and rise to the surface, releasing a puff or a swirl of glowing mucous that is brimming with tiny eggs, as Dimitri Deheyn, a research scientist at the Scripps Institution of Oceanography at the University of California, explained to Laist. The ritual starts 40 to 45 minutes after sunset.

The little swirls of glowing light that females release look like “a field of little cerulean stars across the surface of jet black water,” according to the researchers who published a study in PLOS, documenting the mating ritual. Noticing the glow flitting through the dark waters, the males homing in are attracted to the light. They streak upwards from the bottom, and with an explosion of light, they eject gametes, projecting one of the most magical spectacles of biological luminescence ever recorded.

When Coyne filmed it with his camera, he said, it was “one of the coolest things I have ever seen.” Adding to the explanation, he said that the ritual only lasts for about 20 minutes. The footage he shared shows a female zigzagging and spiralling through the waters, carving a trail of glowing turquoise green light. In a few moments, a male emerges and begins mating with the female, dissolving in her light and releasing gametes into the water. And with this little crashing and flaring, the eruption quietens down. The fireworms disappear into the night. The glow dims down, ultimately dissolving into the dim waters.

Coyne revealed that filming this scene was extremely challenging because “each fireworm is only about an inch long and they move very quickly.” He attributed @foxseacharter for spotting the worms, initially, but didn’t share the exact location to preserve the privacy and safety of the glowing worms. Meanwhile, the footage left viewers wonderstruck. @mel2022_mil said, “This is a reminder that we live in a beautiful world and we shouldn’t take it for granted.” @aylas_nature_photography added, “Wow! Never knew they existed!” And if you are swimming in an area and you come across this mating sight, don’t freak out. The glowing mucous released by the females is “totally organic,” a scientist told Laist.

You can follow Patrick Coyne (@patrickc_la) on Instagram to watch more surreal videos on bioluminescence.

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