Sea Lions And Dolphins Are Dying By The Hundreds Along California's Coast. Toxic Algae Might Be The Culprit

Hundreds of dead and injured sea lions and more than 100 dolphins have washed up on beaches across Ventura and Santa Barbara counties in recent weeks, potentially due to a harmful algal bloom off the coast.

“I would expect that we will continue to see dead animals washing up on the beaches,” said Justin Greenman, assistant stranding coordinator with the National Oceanic and Atmospheric Administration. “The event’s not stopping, it's expanding to L.A. and Orange County.”

While algal blooms are a normal occurrence, severe ones can produce large amounts of domoic acid, which ends up in the bodies of small prey fish like sardines, which eat algae. When sea lions and dolphins consume the toxic sardines, the domoic acid builds up inside of them, causing domoic acid toxicosis, which impacts their brains and hearts.

Many animals die due to heart failure, while others end up on the beach, disoriented, having seizures and, in the cases of some dolphins during this event, miscarriages.

“This is definitely the largest thing I’ve seen with marine mammals. And it’s hard when some of these environmental things come up and you’re left helpless,” said Greenman.

If you see a sea lion just standing there, confused, bobbing around on the beach in the coming weeks, domoic acid poisoning could be the cause.

Stranded animals can bite and carry disease, so avoid approaching any.

While sea lions can sometimes be treated, common dolphins (those currently washing up), can’t be, according to Greenman. In many cases, animals will be euthanized. The problem's so big right now that marine mammal treatment centers across Southern California are completely overwhelmed.

When it comes to dead bodies, it’s up to those that oversee each individual beach to decide what to do with them. Many municipalities clean them up, while on state beaches they’re often left to decompose, becoming food for other ocean creatures.

You can report a stranding by calling the West Coast Marine Mammal Stranding Network at (866) 767-6114.