A dramatic outbreak of kelp-eating sea urchins along the Central Coast of California in 2014, leading to a significant reduction in the region's kelp ...
"They prefer kelp, but they had eaten all the kelp, so they moved up into shallower water and that allowed the kelp to regrow on the deeper reef," Smith said. In 2018, for example, they went out to a site that had been an urchin barren the previous year and found a kelp forest. In the new study, Smith and Tinker found no evidence of an unusual pulse of juvenile sea urchins increasing the population in 2014. A series of major disruptions to California's kelp forest ecosystems began in 2013 with the emergence of sea star wasting disease, which wiped out a sea urchin predator, the sunflower sea star. "In 2014, they came storming out of the crevices looking for kelp," Smith said. In subsequent years, sea urchin movements enabled kelp forest recovery at sites that had been denuded "urchin barrens."