A notable increase in sick California sea lions along the Central California coast has prompted concern among animal specialists, who attribute the condition to a brain-altering toxin found in harmful algae blooms. The Marine Mammal Center has rescued approximately 15 to 20 sea lions over a three-day period in Monterey County, with most suspected of suffering from domoic acid poisoning.
Domoic acid, a neurotoxin, attacks the brain and heart, leading to symptoms such as seizures and heart failure. If left untreated, the toxin can cause permanent brain damage. While the toxin can naturally flush from an animal's system over time, repeated exposure can result in more severe and long-lasting effects. Affected animals may become disoriented, experience seizures, and display unpredictable behaviors.
According to Giancarlo Rulli, a spokesperson for the Marine Mammal Center, the majority of affected animals in the current hotspot are large, subadult, and adult California sea lions. Veterinarian Laura Campbell noted that symptoms range from uncoordinated movements to active seizures.
The center is receiving daily calls reporting sick sea lions, particularly in its Monterey Bay operations. While the exact cause for the current surge is not yet understood, the center is actively working to rescue these animals and transport them to its hospital in Sausalito for treatment. Four sea lions are currently undergoing triage in Castroville.
Officials anticipate an increase in reported cases and are advising the public to maintain distance from any sick sea lions and to contact the center if such an animal is spotted. Three deceased sea lions were recently found at Moss Landing State Beach in Monterey County. Rulli emphasized that the affected animals are not behaving normally and that their cognitive functions and behavior can become unpredictable due to the toxin's impact.