06 • 22 • 2020

New Survey Tracks Health Issues From Red Tide Exposure in Southern CA

By Katie Day

Did you head to the beach in Northern Baja or Southern California between March 30 and May 31, 2020? If so, help us collect important public health and scientific information related to the prolonged red tide by filling out this quick and easy questionnaire (también disponible en español, haz clic aquí)!

The Surfrider Foundation, Southern California Coastal Ocean Observing System (SCCOOS) and researchers at Scripps Institution of Oceanography have collaborated on an effort to collect community anecdotal information on potential respiratory symptoms experienced after being exposed to a recent red tide in Southern California. Collected information will be included in future publications and bulletins exploring the impacts of this type of phytoplankton bloom.

From March 30 to May 31, 2020, record breaking counts of Lingulodinium polyedra (L. polyedra), a species of phytoplankton that created a red tide off the coast of California, were reported at beaches from Tijuana to Ventura. During the day, a thick brown-red plume could be seen at beaches and bays across the region. At night, the plume would turn into a bioluminescent show with bright blue glowing waves and shore break (image below by Michael Latz, PhD).

A red tide is the result of a large bloom of phytoplankton (counts can range from thousands to millions of cells per liter of seawater), a natural phenomenon that gets exacerbated by nutrient runoff and warming waters. The type of phytoplankton that makes up red tide blooms varies by region and toxicity. While most species of phytoplankton are harmless, and actually essential to the Earth’s oxygen production and marine ecosystem, some can be notably harmful to humans and marine life. Read more about the impacts of red tides in coastal communities across the US in this beachapedia article.

While this recent red tide was composed of a phytoplankton considered to be less toxic than other red tide culprits (like Karenia brevis off Florida and species that produce Domoic acid off the West Coast) there have been anecdotal reports of respiratory symptoms developing after L. polyedra exposure for years. 

To help track these instances and collect more targeted anecdotal reports of respiratory symptoms, Surfrider worked with SCCOOS and Scripps Institution of Oceanography to develop this questionnaire. The goal is to use this anecdotal information in future publications and to support future research efforts to track potential adverse health impacts of L. polyedra exposure. 

Help us collect important information by filling out the questionnaire today. 

Learn more about the recent prolonged red tide from Surfrider San Diego!