Toxic algae bloom endangering hundreds of marine mammals

Sick or dying sea lions and other marine mammals have been increasingly found on Southern California beaches due to a widespread toxic algae bloom, Los Angeles County’s animal control director said Tuesday, and she urged residents to avoid contact with the animals if they encounter them while visiting the coastline.

Marcia Mayeda, the county’s animal control and care director, told the Board of Supervisors more than 1,000 marine mammals have been found sickened or dead on beaches between Orange and San Luis Obispo counties. In addition to sea lions, dozens of dolphins have also been affected, she said.

“The problem is something called domoic acid, which is a neurotoxin produced by the bloom of toxic marine algae called pseudo-nitszchia,” Mayeda told the board.

She said the toxin damages the brains of marine mammals, leaving them dazed and lethargic on  beaches, often leading to death.

Sea lions are particularly susceptible due to their foraging habits, which involve devouring the shellfish that eat the deadly algae, Mayeda said.

With treatment, the sea lions can recover within 72 hours, she said. But some retain brain damage, resulting in memory loss. The damage is determined by how much tainted seafood the animal has devoured.

Mayeda said her agency “is not equipped to handle marine mammals.” But she said county officials have reached out to state agencies, zoos, aquariums and other nonprofit organizations for help in assisting or saving the stricken animals. She urged beachgoers to leave sick marine mammals alone to avoid injuring the animals or getting hurt themselves.

Officials at the Marine Mammal Care Center in San Pedro echoed that advice.

“It is important for the public to know that animals who have ingested domoic acid pose a very serious public health and safety risk,” MMCC CEO John Warner said in a statement issued earlier this month. “Adult seals and sea lions with DA can present in unpredictable ways, including increased aggressiveness and lethargy and unresponsiveness. Please keep your distance from animals you see on the beach and immediately call us if you suspect an animal is in distress.”

According to MMCC, the center rescued 47 sickened sea lions during a two-week period of early June. The center is currently treating more than 100 ill sea lions. It is being assisted by the Los Angeles Unified School District, which is providing temporary outdoor space for the center to treat the animals.

“If there is a need for an amplification of the space, we’ll be here to provide it,” LAUSD Superintendent Alberto Carvalho said during a news conference at the expanded treatment area Tuesday. “We have the workforce that did this initial work and are ready to do more should the need arise.”

The district has long partnered with the MMCC on environmental and coastal conservation education programs.

Anyone who encounters an animal that may be suffering was urged to contact the center at 800-39-WHALE (94253). The center is also looking for people interested in volunteering to assist the animals or donating to the cause. More details are available online at marinemammalcare.org.

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