Sea lions and other marine mammals in Southern California are facing a serious health crisis due to a harmful algal bloom. This event, described by experts as one of the worst in recent memory, is causing widespread poisoning among these animals, leading to alarming incidents along the coast.
Recently, a surfer off the Ventura County coast experienced a terrifying encounter with a sea lion that he described as “feral, almost demonic.” The surfer, Rj LaMendola, was bitten while on his board, and the sea lion aggressively pursued him. After the incident, he contacted local wildlife officials, who indicated that the animal’s behavior was likely linked to toxic algae in the water.
The poisoning is caused by domoic acid, a neurotoxin produced by harmful algal blooms. Ingesting this toxin can lead to severe symptoms in sea lions, including seizures and a behavior known as “stargazing,” where the animals crane their heads back. In some cases, they may even fall into a comatose state. Experts warn beachgoers to avoid sick animals, as they can become aggressive without warning.
Rescue teams are struggling to cope with the surge in cases. As of last Friday, over 140 sea lions showing signs of poisoning were brought to the Marine Mammal Care Center in San Pedro. Additionally, at least 50 dolphins have been found stranded in the area, many of which are euthanized due to the high mortality rate associated with domoic acid poisoning.
Domoic acid accumulates in filter-feeding fish, such as anchovies and sardines, which are then consumed by sea lions and dolphins. The survival rate for sea lions receiving timely treatment is between 50% and 65%. However, the current situation is particularly dire, with more male sea lions succumbing to the toxin than in previous years.
The algal bloom, which began about a month ago, is more severe than a similar event in 2023 that resulted in the deaths of over 1,000 sea lions. Experts attribute the increase in frequency and intensity of these blooms to climate change and human activities, such as agricultural runoff, which feed the algae.
Treatment for affected sea lions involves tube feeding and intravenous fluids to provide nutrition and medication. The longer the bloom lasts, the greater the risk of permanent brain damage for the animals. If they cannot be safely released back into the wild, they may have to be euthanized.
As the Marine Mammal Care Center faces capacity strains, staff are preparing for the upcoming elephant seal pupping season, which will further limit their ability to take in more sea lions. They have called for public support to help manage future stranding events, emphasizing the need for awareness among beachgoers about the proper response to stranded marine animals.
If you see any stranded marine mammals, you should call (800) 399-4253 for rescue assistance. It’s crucial for the public to keep a safe distance, as interactions can be harmful to both the animals and people.