Rescuers are responding to a surge in sea lions sickened by domoic acid, a neurotoxin produced by naturally occurring harmful algal blooms. The Marine Mammal Center says it has already rescued more than 150 sea lions with domoic acid poisoning this year — more than twice its typical annual total.
At San Francisco’s Pier 39, where sea lions have become a tourist attraction, the animals appear healthy and energetic.