From Urchin Crushing to Lab-Grown Kelp, Efforts to save California’s Kelp Forests Show Promise

By Julie Watson.

CASPAR BEACH, Calif. (AP) — A welding hammer strapped to her wrist, Joy Hollenback slipped on blue fins and swam into the churning, chilly Pacific surf one fall morning to do her part to save Northern California’s vanishing kelp forests.

Hollenback floated on the swaying surface to regulate her breathing before free diving into the murky depths toward the seafloor. There, she spotted her target: voracious, kelp-devouring purple urchins.

Within seconds she smashed 20 to smithereens. “If you’re angry, it’s a cathartic way to get it all out,” Hollenback joked. “It’s ecologically sanctioned mayhem.”

The veterinarian who lives in Berkeley, California is part of a crew of volunteers who swim, snorkel and dive armed with pick axes and hammers on a sole mission: To crush purple urchins that largely destroyed 96% of California’s iconic bull kelp forests between 2014 and 2020, and with it harmed red abalone and other sea life they supported.

The pilot project off the Mendocino County coast is one of many initiatives California is testing to save such leafy marine ecosystems, which are declining worldwide due to climate change.

Kelp forests play an integral role in the health of the world’s oceans, one of the issues being discussed at the United Nations climate summit in Dubai.Based on early observations, efforts like urchin culling appear to be helping.Biologists say they have started to see small successes with the experiments started several years ago, offering hope of reversing destruction likened to a rainforest being clear-cut.Healthy patches of kelp and schools of fish returned this summer to small sections where urchins were crushed at Caspar Cove, 160 miles (200 kilometers) north of San Francisco.

Nearby at Albion Bay, where commercial divers removed many of the urchins in 2021, biologists put tiny kelp grown in a lab on 98-foot (30-meter) lines. In August, they discovered the kelp not only had reached the surface, but was reproducing.