A welding hammer strapped to her wrist, Joy Hollenback slipped on blue fins and swam into the churning, chilly Pacific surf one fall morning to do her part to save Northern California's vanishing kelp forests.
Hollenback floated on the swaying surface to regulate her breathing before free diving into the murky depths toward the seafloor. There, she spotted her target: voracious, kelp-devouring purple urchins.
