March 11, 2019 — Purple urchins were not getting a lot of love at the cove across Highway 1 from Van Damme State Park on Saturday morning. Urchins have an insatiable appetite for kelp and very few predators, which leads to a near-barren underwater landscape.
In the latest effort to reduce their population, 46 volunteer divers, from first-timers to pros, pried about half a ton of the ravenous herbivores off the ocean floor and sent them to a compost pile.
That population has exploded, according to Joshua Russo, president of the Watermen’s Alliance, a council of divers groups and spearfishing clubs that advocates for sustainable fisheries. Russo said the group raised $130,000 last year to hire divers to pull urchins out of four coves in Mendocino and Sonoma counties on any diveable day from January to August. Saturday’s volunteer event, also organized by the Watermen’s Alliance, was in conjunction with that months’-long effort because the hired divers, who were all on boats, couldn’t come in as shallow as the volunteers, who go in from the shore.
It’s too soon to say if the urchin removal is restoring balance to the underwater ecosystem, according to Tristin McHugh, the North Coast Regional Manager of Reef Check, an organization that collects data about reefs and kelp forests and works to make that data available to the public. But McHugh was heartened by the overwhelming display of concern for the health of the cove, which has long been a favorite abalone diving spot. Reef Check will continue monitoring areas where urchins have been removed, and working with groups like the Watermen’s Alliance and Urchinomics, an organization that seeks to restore kelp forests by making urchins commercially viable.
Come with us as we take a long, cold walk on the beach and hear about data, diving, and the right way to coax an urchin out of its shell.