It’s a dance as old as the tides. Long before whales sang or seabirds wheeled through salty air, forests rose from the seafloor, unfurling blades toward the sun. Over eons, kelp evolved exquisite ways to bend to the sea’s rhythms, but its ballet is no mere performance. With stipes stretching up to 100 feet or more, kelp forests produce oxygen, store carbon, prevent coastal erosion and shelter a vast array of marine life.

These vital ecosystems now face unprecedented threats. As ocean waters warm and voracious grazers like purple sea urchins multiply, California’s lush kelp forests have declined by up to 90 percent. Pushed to the brink, kelp is altering its choreography.