SoCal Overrun as Sick Mammals Wash Ashore Amid Toxic Bloom

Sea lions, dolphins and seabirds have been beaching themselves in large numbers along the SoCal coasts because of an algal bloom, which is commonly known as the “red tide,” but the bloom contains toxic neurotoxins, creating an unheard number of sick mammals.

The coast is experiencing the bloom of a harmful algae from an organism called Pseudeo-nitzschia. This is one of the many algae that inhabit the water typically during spring or fall, but what is creating unheard-of reactions from these usually harmless mammals is a toxin released called domoic acid.

The toxins start in small fish, which are the mammal’s main food source. Common behaviors when a mammal is sick are seizures, head bobbing, which deeply affects the central nervous system and causes aggression and tremors.

Up the coast in Oxnard on March 21, RJ LaMendola’s surf session was cut short by a sea lion attack which the animal ended up puncturing his wetsuit and piercing his skin.

Then on March 30, Phoebe Beltran, 15, was bitten by a sea lion while doing her swim test for junior lifeguards in Long Beach. Her arm was bitten in many places, but she is recovering well.

At the end of March, the West Coast Marine Mammal Stranding Network was reporting up to 100 calls a day about animals in distress on the shores. The influx of sea lions has been overwhelming for marine centers.

The movement of this issue is happening so fast that it is concerning whether there are enough resources to help the animals. The largest event on record was in 2023 and it is unsure if this year’s algal bloom event will surpass, but it is looking likely that it will be record-breaking once again.

This is SoCal’s fourth year in a row seeing domoic acid blooms in the algae but what has changed this year is the rubble of burnt homes left on the shores after the Palisades fire in January.

Experts, such as the nonprofit “Heal the Bay” have been testing the water and found an increase in heavy metals. Since this is a recurring algal bloom and mammals have all the symptoms of domoic acid toxicosis, the post-wildfire debris is just an overall concern to marine life and water safety.