San Diego

Toxic algae is causing sick sea animals to wash up on California shores. Here's what you should know

Fifteen seals and sea lions in San Diego have been treated for toxic acid exposure so far, and more will likely need treatment

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Sea animals are washing up on San Diego shores lost and confused, and some of them are very sick.

It’s because of a toxic algae bloom that started north of San Diego and spread south.

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Fifteen seals and sea lions in San Diego have been treated for toxic acid exposure so far, and this number will likely grow.

“This is this is the largest bloom I've seen in my career,” said Dr. Kelsey Herrick, a veterinarian with SeaWorld San Diego. “Up in Santa Barbara County and Ventura County, that's where the initial very big bloom happened and that's where the bulk of the animals were stranding. So, thousands of sea lions and hundreds of dolphins.”

She said San Diego is seeing the least of the illness in the state, but it’s getting worse here, too.

It starts with something called domoic acid. The acid is a potent neurotoxin that lives in algae and enters the food chain once shellfish eat it. It’s harmless to shellfish but can be deadly to mammals as the toxin gradually makes its way up the food chain.

Thanks to rehabilitation by the SeaWorld San Diego Rescue Team, the sea lion that was spotted on a San Diego freeway in January is back in the ocean after roughly a month of treatment.

Veterinarians can rehab most sea mammals, but not all.

“Some of them do need to be humanely euthanized,” Dr. Herrick said. “Some of them have actually irreversible brain damage from the toxin. And so for animals that are that affected, unfortunately, there's no way to treat that.”

A tell-tale sign of an animal that’s been infected is the animal washing up on the shore appearing disoriented.

“We've seen animals walking on roads or walking into people's private properties on the beaches,” Dr. Herrick said. “So just anything like really, really abnormal.”

Toxic algae and 'Freeway' the sea lion

Some San Diegans might remember "Freeway" the sea lion, who was repeatedly found far inland. Freeway died in April 2023. A progressive disease had done enough damage that SeaWorld opted to euthanize him to prevent suffering, the park said at the time.

In June of 2022, a different sea lion wandered onto a Carlsbad golf course, miles from the beach.

A spokesperson for SeaWorld, Tracy Spahr, confirmed that Freeway may have also been a victim of the algae back in 2021. In retrospect, the sea lion was showing signs that could be interpreted as a symptom of a neurological infection.

An elderly couple in their late 80s and their disabled grandson died in an over night house fire in El Cajon, the Supreme Court Preserved Access to Abortion Pill for Now, and the sealion nicknamed, freeway after wandering onto SR-94 passed away Thursday. Here is San Diego News Daily for April 22, 2023.

Who to call to help sick sea animals

One of the biggest things for tourists and San Diegans to remember if they see a sea animal washed up on shore looking delirious is don't try to approach it. Rather, call the SeaWorld helpline at 1-800-541-SEAL (7325) and a rescue team can come out to help.

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