A surge in sea lion strandings along a significant stretch of the California coastline has raised concerns among experts, who suspect a bloom of harmful algae as the culprit. The Channel Islands Marine & Wildlife Institute reported a significant increase in daily reports of sick sea lions spanning 155 miles of shoreline in Santa Barbara and Ventura counties since July 26. These marine mammals are exhibiting symptoms consistent with domoic acid poisoning, a neurotoxin produced by algae that affects the brain and heart.
The institute’s statement confirmed that the poisoning event primarily affects adult female California sea lions. They have successfully rescued 23 animals so far. Coastal Vandenberg Space Force Base released images documenting the rescue of stranded sea lions from one of its beaches on July 29.
The occurrence of domoic acid poisoning along the California coast is not uncommon, according to NOAA Fisheries. Last year’s outbreak was particularly severe, resulting in the deaths of hundreds of sea lions and dozens of dolphins within the first weeks of June. The poison enters the food chain when microscopic algae are consumed by shellfish and small fish, which are subsequently eaten by sea lions, dolphins, and birds.
Affected sea lions often exhibit a range of symptoms, including disorientation, head weaving, foaming at the mouth, and seizures. It’s important to note that humans can also be affected by domoic acid poisoning if they consume contaminated seafood.
