Learn more about an algae bloom that's causing sea lions to act erratically, leading to a few cases of aggression.
An image of three sea lions swimming in the ocean unrelated to the toxic algae bloom. (Image Credit: David Keep/Shutterstock) Sea lions are typically not aggressive toward humans. However, these usually curious and playful marine animals have been making headlines recently for multiple attacks on people off the coast of California. The aggression is linked to a toxic algae bloom impacting nearly 400 miles of the Southern California coast, mostly in L.A. and Santa Barbara Counties. Aggressive and erratic behavior isn't the only way this toxic bloom can affect these animals, and sea lions aren't the only infected animals. Sea Lion Attacks Recently in March 2025, two people in Southern California were attacked by an aggressive sea lion. One man was on his surfboard when the sea lion charged, bit him, and dragged him off the surfboard. The Californian, Rj LaMendola, recounted his experience on a Facebook post. In it, he explained how the sea lion seemed "...feral, almost demonic, devoid of the curiosity or playfulness." A similar incident occurred when a 15-year-old was in the water taking a swim test to be a lifeguard. The sea lion approached Phoebe Beltran while she was in the water and repeatedly bit her in the arm. Both LaMendola and Beltran are recovering from their injuries. Read More: What Is Red Tide – and Is It Getting Worse? Why are Sea Lions Attacking People? It's likely that sea lions are becoming aggressive toward people because of a toxic algae bloom.…