Toxic algae bloom killing dolphins and other marine animals along Southern California coast, experts say

LOS ANGELES — Dozens of marine animals, including an unprecedented number of dolphins, are dying due to a toxic algae bloom now stretching from San Diego to San Luis Obispo. The entire shoreline is an extreme danger zone due to a neurotoxin called domoic acid or DA.

This is the fourth year in a row that this has happened, and experts say this is the worst yet.

A map from the Southern California Coastal Ocean Observing System shows the high amount of domoic acid at the center of the toxic algae bloom now engulfing the Southern California coast and killing numerous animals.

“It’s the worst we’ve ever seen here in Southern California on many different fronts, but dolphin strandings, it’s unprecedented,” said John Warner, the CEO of the Marine Mammal Care Center in Los Angeles.

In the past week, there have been more than 50 dead and dying dolphins found along the L.A. County coast. There were 16 in San Diego on Sunday alone.

“It’s really been consistently severe, the number of animals coming up on the beaches, either with seizures or dead or dying, has continued at a pretty high rate,” said Michael Milstein with NOAA Fisheries, West Coast Region.

Sea lions are traditionally the main victims of a toxic algae bloom, which can cause them to turn aggressive and attack beachgoers. But now, the toxic algae bloom is moving further up the food chain.

READ MORE: Aggressive sea lion caught on video at Newport Beach euthanized after chasing surfers

Shocking video shows an aggressive sea lion actively going after people in the water and on shore. Experts say a toxic algae bloom in the water is making marine mammals sick and changing their behavior.

Researchers say a minke whale found in the Port of Long Beach and a young gray whale in Huntington Beach both died due to domoic acid toxicity.

“It is a natural phenomenon that happens because of offshore winds, cold water upwelling, but it can be fed and sort of put on steroids by the things we’re doing,” Warner said.

Debris from the wildfires and fertilizer runoff are helping to fuel the toxic algae, which are eaten by small fish, which are then eaten by marine mammals and birds, causing a potentially deadly toxic overdose.

While sea lions and birds can be saved, it is 100% fatal for dolphins.

As researchers are sounding the alarm, they are also holding hope that the beloved animals won’t suffer any long-term damage.

“We know these populations are resilient, strong and can bounce back from this relatively quickly, provided they have the food and other resources they need,” Millstein said.

At this point, experts say they see little hope for immediate relief given how widespread and well-fed the algae bloom is.

Copyright © 2025 KABC Television, LLC. All rights reserved.

You May Also Like

King Charles jokes about aging with Elton John in birthday podcast appearance

King Charles Jokes About Aging With Elton John on Birthday Podcast

King Charles III marked his 78th birthday with a special appearance on…
Zohran Mamdani taps ex-NYC DSA co-chair as 'nightlife mayor'

Zohran Mamdani Taps Former NYC DSA Co-Chair as Nightlife Mayor

New York City Mayor Zohran Mamdani has chosen a longtime socialist organizer…
Ex-NFL punter sues NCAA after heartbreaking Parkinson's diagnosis

Former NFL Punter Sues NCAA After Devastating Parkinson’s Diagnosis

Former NFL punter turned orthopedic surgeon Patrick O’Neill is suing the NCAA,…
Massive waves up to 60 feet threaten Northern California coast as NWS issues urgent warning

NWS Warns of Massive 60-Foot Waves Along Northern California Coast

Powerful waves pounded Northern California’s shoreline Saturday, prompting forecasters to issue urgent…
I'll Drink to That: Drunk VA Raccoon's Wild Night Turns Into a $290K Windfall for Shelter Animals

Drunk Virginia Raccoon’s Wild Night Raises $290K for Shelters

I have a family of raccoons in my backyard, and although I…
Marco Rubio's daughter steals the show at his first post-midterm speech: ‘I don’t know where she got this!’

Marco Rubio’s Daughter Draws Attention at His First Post-Midterm Speech

Secretary of State Marco Rubio proudly watched as his daughter Daniella introduced…
Sexual predator deported to Mexico hauled back to US for assault and murder of American mom

Sex Offender Deported to Mexico Charged in U.S. Mom’s Assault, Murder

A Mexican serial rapist who murdered an American woman more than two…
Jonathan Kreiss-Tomkins becomes first Democrat since 1998 elected governor in Alaska

Jonathan Kreiss-Tomkins Is Alaska’s First Democratic Governor Since 1998

Alaska voters have chosen a Democrat for governor for the first time…
Two Americans drown after Caribbean current pulls them out to sea

Two American Tourists Drown After Caribbean Current Sweeps Them Out to Sea

Two American tourists died after being caught in a powerful current while…
SpaceX’s Starship soars into orbit — after booster explodes in Gulf of Mexico

SpaceX Starship Reaches Orbit After Booster Explodes in Gulf

SpaceX’s effort to bring its entire Starship vehicle back to the launch…
Inside Arab nation's battle against radicalism as top official warns of threat brewing on Europe's streets

Inside an Arab Nation’s Fight Against Radicalism as Senior Official Warns of Growing Threat on Europe’s Streets

— A senior Emirati official says demonstrations in Europe have moved beyond…
Tanker that slammed into docked NOLA riverboat had history of navigational systems issues: report

Report: Tanker That Hit Docked New Orleans Riverboat Had Prior Navigation System Problems

The tanker that crashed into a New Orleans riverboat while it was…