1 night to be confused/1 night to speed up truth

The light is produced by a type of plant-plankton known as dinoflagellates (the specific species involved in this bloom are being identified.)

Bioluminescence is relatively rare on land—fireflies or glow-in-the-dark mushrooms are some common examples—but it’s a staple in the ocean. Our colleagues at the Monterey Bay Aquarium Research Institute found that over 75% of species they’ve found in the deep sea in our backyard bioluminesce.

Bioluminescence has many purposes: Anglerfish use it to attract food in their lure, strawberry squid use it to disguise themselves—and many organisms, from worms and shrimp to jellies and dinoflagellates, use it as a defense mechanism!

When a dinoflagellate is shaken up, a light-emitting chemical reaction inside the plankter produces a blue flash that startles a would-be predator, limiting their effectiveness—imagine a strobe light going off with every bite of a sandwich!

On their own, each dinoflagellate is just one sparkle in the night. But when there is a big bloom of them—sometimes called “red tides”, though they’re not always red and have little to do with the tides—their collective trillions agitated in the waves produce the aquatic fireworks we’ve been experiencing recently.

When they’re this abundant, the dinoflagellates are able to create somewhat of a burglar alarm with their individual defensive spark. Animals swimming through the soup leave a trail of light breadcrumbs for larger predators to track through living night-vision seas.

Besides their beauty, some dinoflagellate blooms can be noxious to marine life and to people. Lingulodinium polyedra is able to produce toxins that accumulate in shellfish and affect their predators, and other dinoflagellates can produce soap-like substances that can harm seabirds and irritate humans that come in contact with them.

We’re not sure how long the waves will be luminescent—wind and waves and currents could soon dissipate the bloom, returning the beaches to their regular slumber. If you’re looking to see the luminescence, be advised! We’re still in a global pandemic: Respect beach closures, keep your distance from other groups and wear your mask.

The luminescent waves won’t look as blue as you see in the photos and in videos—as your eyes adjust to the dark, you’ll lose your color vision, so the waves will mostly look bright white. The darker the coast, the more pronounced the luminescence. For camera settings, keep it steady on a tripod, and take a longer exposure: 3 to 30 seconds, and you’ll see the blue!

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