Purple Sea Urchin populations have exploded along the northern California coast, creating “urchin barrens” where all the algae has been eaten – including Giant Kelp and Bull Kelp – leading to the loss of most of the vital “kelp forest” habitat. Dr. James Estes, emeritus professor of Ecology at the University of California – Santa Cruz, one of the foremost experts on Sea Otters, explains how the disappearance of these predators a century ago contributed to the loss of kelp forests here and elsewhere.
The situation in one graphic, from the NAS Facebook page :
Dr. Estes is a renowned scientist and his lifetime of research is documented in his book, Serendipity: An Ecologist’s Quest to Understand Nature (University of California Press, 2016). (article about the book) (reviewed in Nature) He and his work also feature prominently in the film The Serengeti Rules, now playing in theaters. Some of his lectures and presentations are on YouTube and a Web search will lead to pages of references, scientific publication, videos, and other information.