Along some seventy plus miles of southern California coastline, usually curious and playful sea lions are attacking humans in the water. At unprecedented levels, the animals are being poisoned by the

A common neurotoxin produced by algae blooms is making California sea lions more aggressive. Here’s why it has the power to change behavior—and the danger it poses.

Marine experts say these attacks are not common, but are happening more often. That’s due to a toxic algae bloom that are poisoning marine mammals, making them become aggressive and violent as they travel to shallow water and get closer to humans.