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.

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