Monday March 31, 2025
NOAA Fisheries —
Harmful algae blooming off the coast of Southern California has poisoned scores of California sea lions and common dolphins that are stranding in large numbers on area beaches.
West Coast Marine Mammal Stranding Network partners are reporting upwards of 100 calls a day reporting sea lions and dolphins affected by the algal toxin, domoic acid. Some animals experience seizures on the beach, or may appear to bob their head, while others have died. Beachgoers should remain a safe distance (a minimum of 50 yards) from affected animals—they can act erratically under the influence of the biotoxin.
In some cases, teams from marine life care centers are bypassing animals with severe domoic acid poisoning and focusing on those that have the greatest chance of recovering.
“We are having to do triage on the beach as we try to identify those animals where we have the greatest chance of making a difference,” said John Warner, chief executive officer of the Marine Mammal Care Center in Los Angeles. He said teams responding to strandings have sometimes found dolphins swimming in circles in shallow water near the beach.