Community Corner

Red Tide Spotted in Imperial Beach, Coronado

Beachgoers and lifeguards have seen blooms of dinoflagellates known as red tide in Imperial Beach and Coronado in recent weeks. At night the red tide gives off a bioluminescent neon blue glow.

A red tide has rolled into Imperial Beach and Coronado, lifeguards said.

Red tides occur when large amounts of dinoflagellates bloom in the water, giving ocean water a red or brown color.

The red tide started about two weeks ago, went away then came back again, said Imperial Beach lifeguard captain Robert Stabenow. Sightings have also been reported by Coronado and Silver Strand State Beach lifeguards in the past week.

Questions of safety have thrown a lot of people off guard in Imperial Beach, where contamination from the Tijuana River is a common concern in the rain season, Stabenow said. 

"Red tides are pretty common this time of year," he said. "There's no harmful effects of the red tide to anybody. It's safe to be in contact with water."

At night dinoflagellates give off a neon blue bioluminescence. 

"I know some people like to go surfing at night in IB. When you're paddling out there it creates a nice trail [of bioluminescence]," Stabenow said.

Visit the Latz Laboratory website or this FAQ by Dr. Peter J.S. Franks of UC San Diego for more information about red tides.


Get more local news delivered straight to your inbox. Sign up for free Patch newsletters and alerts.

We’ve removed the ability to reply as we work to make improvements. Learn more here