Phytoplankton light ups the ocean

If you`re wondering why the ocean has a red tint to it or why it`s glowing in the dark, you`re not alone. The phenomenon known as a 'red tide' is taking place off our shores right now and people are lining up on our beaches to see it.

The phytoplankton in the ocean is blooming right now and it's a natural occurrence.

"It came out from a blackness to a brilliant white, and then to this beautiful turquoise that just illuminated," described Sandy Giberson of Pacific Beach.

The phytoplankton contains a red pigment that captures sunlight for nourishment, and reproduction. When they begin reproducing rapidly, and millions of them are in a concentrated area, the pigment intensifies. At night it creates a bright glow like blue propane fire on the water.


"It was really cool," said Deana Chadwick who is visiting from Connecticut, as watched from Pacific Beach. "It looked like a big fluorescent glowing spot across the wave. It almost looked like a glow stick in the water."

The phenomenon gets the name "red tide because the water appears red or brown during the day. Although it happens in many places around the world, off of California it's is spotted most frequently from San Diego to Santa Barbara during the warm months of early spring through late summer. Unlike other places in the world, the phytoplankton here is non-toxic.

"It's perfect nutrients for them," said Nigella Hillgarth, PhD, who is the Executive Director of Scripps Birch Aquarium. "It's perfect temperature and it's nice and calm. There's no wind to disperse them right now."

The microscopic algae is important to the eco-system because it is the basis of the food chain in the ocean. It feeds slightly larger zoo-plankton which in turn feeds krill and small which in turn feed larger fish and everything from sea lions to whales.

A red tide can last anywhere from a few days to a month, but there's no exact way of determining how long it will last. Factors such as sunlight, ocean life feeding on it, wind, and ocean currents all play a role in how long it will last.