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Public Urged to Keep Distance From Sickened Marine Animals

Jul 01, 2023 11:50PM ● By Jeanne Fratello

A sick sea lion is stranded on the beach. Photo via Marine Mammal Care Center.

What do you do if you see a stranded sea lion or dolphin? Leave them alone - resisting the urge to take selfies with them or move them - and call the experts for help.

The rapid growth of harmful algae along parts of the Southern California Coast is suspected to
be the cause of death and stranding for scores of California sea lions and dolphins throughout Los Angeles County, according to the San Pedro-based Marine Mammal Care Center (MMCC). (A sea lion was spotted on the sand just south of the Manhattan Beach Pier last week.)

The MMCC, which rescues and rehabilitates marine mammals along the coastline from Malibu to Seal Beach, has seen rescue numbers leap in the past two weeks and anticipates that the trend will continue. The organization currently has more than 120 marine mammal patients in its hospital, and is scrambling to respond.

“The center is dealing with an enormous increase in reports of marine mammals in distress each day,” said John Warner, CEO of the MMCC, said in a statement. “We are doing the best we can to keep up with the intense pace, and, if history is any indication, we can expect to see anywhere from 75 to 150 animals in need of rescue over the next four to six weeks.”

Above all, Warner urged members of the public to stay away from any animals they discover on the beach and to continue to report all sick and injured marine mammals by calling the MMCC Rescue Hotline at 1 (800) 39-WHALE.

“It is important for the public to know that animals who have ingested domoic acid (DA) pose a very serious public health and safety risk,” he said. “Adult seals and sea lions with DA can present in unpredictable ways, including increased aggressiveness or 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.”

Officials have said that due to marine hospitals being filled to capacity, there is a chance that some marine mammals may be stranded on the beach for a while before they can be rescued. MMCC recommends keeping a distance of at least 50 feet from a sick or injured marine mammal.

California sea lions, like all marine mammals, are protected under the Marine Mammal Protection Act.

Algae Blooms Producing Neurotoxin

The current wave of illness among marine mammals was set off by toxic algal blooms off the coast of California. This algae produces a neurotoxin called domoic acid, which accumulates in fish such as sardines, anchovies, and squid. The toxin then transfers to predators such as sea lions and birds that prey on the fish — causing seizures, brain damage, and sometimes death.

According to the National Oceanic Atmospheric Administration, domoic acid, a harmful algal toxin, is one of the foremost threats to marine animals. (While experts say domoic acid is not harmful to humans through water contact, people are urged not to enter the water if they see an algae bloom.) Experts are not sure when the current bloom will subside.

Sea lions with domoic acid often suffer from seizures, dehydration, severe vomiting, aggressive behavior or lethargic unresponsiveness, miscarriages, and even death. Treatment for patients with DA involves keeping animals hydrated with fluids given subcutaneously or orally, administering anti-seizure medication, and supporting them nutritionally.

Neurological symptoms in marine mammals can include an unusual side-to-side head movement or their heads extended back for long periods of time. Many female sea lions are pregnant this time of year and may give birth in public places far from their normal rookeries.

(A sea lion sickened by domoic acid. Photo via MMCC.)

Not surprisingly, the massive increase in distressed animals reported to MMCC is putting a strain on its resources as the MMCC continues to deal with the many immature animals already in its care following the annual pup season this spring. As the mature animals recover, each consumes 18 – 21 lbs of food per day, significantly more than the pups and yearlings that MMCC treats more routinely. The amount of food, medications and medical samples needed make treating DA more expensive than its typical patients. Dealing with the current event is likely to cost the non-profit organization more than $250,000.

(Charlie, a sea lion who had been sickened with DA, was successfully treated at the MMCC and has since been released back into the ocean.)

The MMCC is the only year-round hospital for marine animals in Los Angeles County, and close to 10,000 animals have been rehabilitated by its team of staff and volunteers since 1992. A non-profit 501(c)3 organization, MMCC depends on grants and individual contributions to meet the needs of marine mammal patients. Donations can be made at

Manhattan Beach has been known to support sea lions in distress. When two different sea lion pups waddled up to Sand Section doorsteps in late 2020, the MMCC rescued and rehabilitated them, and Manhattan Beach residents jumped in to aid them. A GoFundMe page to support the sea lions pups' rehabilitation raised nearly $2,000.

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