Where once there were forests of kelp in the ocean, there is only water. And sea urchins. A combination of warm water and other ocean conditions battered the bull kelp and allowed the purple sea urchins to run wild, gobbling up everything edible on the sea floor.
Scientists from the University of California-Davis and the California Department of Fish and Wildlife studied two decades of data to mark the abrupt shift (under five years) from kelp forests to urchin barrens. Cynthia Catton, now at CDFW, co-authored the research and is our guest.