See a sea lion acting strangely? Here's what to do

If you're heading to the beach, be on the lookout for sea lions that may appear lethargic, disoriented and aggressive as the result of a harmful algal bloom along the coast.

A number of sick sea lions suffering the deleterious effects of domoic acid toxicosis have shown up in Santa Barbara and Ventura counties, though a few have been spotted in San Luis Obispo, Los Angeles and Orange counties as well. The sea lions, experts say, were likely poisoned after eating small fish in which domoic acid had accumulated.

The bloom may be centered in the Santa Barbara Channel, though it's tough to pinpoint exactly where it is as sea lions feed and travel long distances.

The event is reminiscent of last year when local care centers were overwhelmed.

"I'd say numbers wise it's not quite as bad as last summer, but it's still early," said Sam Dover, executive director of the Wildlife Institute, which has rescued more than 50 sea lions over the past two weeks.

Why does this keep happening?

This is the third year in a row that a harmful algal bloom has resulted in a notable number of sick sea lions showing up on our shores. Upwelling, which brings nutrients up from deep in the ocean toward the surface, stimulates the growth of Pseudo-nitzschia, a diatom that can produce domoic acid. Some blooms last 30 days, while others can go on for months, like in 2015.

"These blooms come and go, but it does seem like over my career, we're just measuring more toxins as these blooms happen," said Clarissa Anderson, director of the Southern California Coastal Ocean Observing System, which monitors domoic acid levels.

Testing seems to indicate that this event started further offshore before moving toward the coast.

"There are reasons to think that certain aspects of the climate and the way that warming is changing the nutrient dynamics in the ocean could be playing a role here and increasing the toxicity of these blooms," Anderson said. Though she added, long term comprehensive monitoring — and a whole lot of good data — is needed to figure out exactly what's going on.

Is the algal bloom harmful to humans?

People also need to be careful about consuming domoic acid. The California Department of Public Health has issued a warning telling people to avoid harvesting and eating clams, scallops or mussels from Santa Barbara County.

Here's how to report a sick sea lion

First of all, don't approach the sick sea lion. Call the experts instead. There are different care centers depending on where you're located:

• San Luis Obispo, north: The Marine Mammal Center at (415) 289-7325
• Santa Barbara, Ventura: Channel Islands Marine & Wildlife Institute at (805) 567-1505
• Los Angeles: Marine Mammal Care Center at (800) 399-4253
• Orange: Pacific Marine Mammal Center at (949) 494-3050

You can also call the National Oceanic and Atmospheric Administration's stranding hotline at (866) 767-6114, and go here to find your local care center.