Fall 2023

146 C A R M E L M A G A Z I N E • F A L L 2 0 2 3 Volunteer Divers Hard atWork Saving the Giant Kelp Forests of Monterey Bay B Y M I CHA E L CHAT F I E LD Photo: Patrick Webster M ost people think of the giant kelp seen along Monterey Bay’s shoreline as “seaweed,” but the truth is, it’s not a weed—it’s not even a plant, but a form of algae. Scientists refer to it fondly as Macrocystis pyrifera and it is one of the planet’s fastest-growing species, shooting up two feet a day in optimal circumstances, sometimes reaching lengths of 175 feet. Kelp is found in the temperate waters of the Southern Hemisphere and along the eastern shores of the Pacific. One would think that with that phenomenal rate of progress it wouldn’t be long before kelp overwhelms the bay—and the wider ocean, for that matter. A spike in Pacific seawater temperature triggered a chain reaction that included an explosion in the sea urchin population. The spiny creatures have decimated the giant kelp forests up and down the western coast.