Phoebe Beltran immediately screamed for help, which is when the animal -- she later found out was a sea lion -- let go of her arm. She was assisted back to the shore and a lifeguard boat patrolling the water brought all the other swimmers to safety,

Phoebe Beltran was in the homestretch of her 1,000-yard swim when she suddenly felt an intense pain as the sea lion bit her right arm.

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.