There are underwater forests spanning millions of acres — but they’re rapidly dying due to climate change and an unlikely predator.
Kelp forests, which are often referred to as the rainforests of the sea, play an important role in fighting climate change. Kelp, which is a type of macroalgae, is estimated to sequester 634 metric tons of CO2 each year — slightly lower than the amount of emissions released from the country’s largest carbon emitter, Texas.
Instead, the kelp forests are being replaced with the “ecological equivalent of a parking lot,” said Tom Ford, the executive director of The Bay Foundation, a nonprofit environmental group in the Santa Monica Bay area.
These “parking lots,” called urchin barrens, occur when thousands of purple urchins enter a kelp forest and mow it down. Urchins, about the size of a golf ball, with purple spikes shooting out from every direction, devour kelp at an astonishing rate. 
Around the world, variables like predator die-off, overfishing, strong storms and warming oceans have caused purple urchin populations to grow and relocate to warmer waters, putting new pressure on kelp forests. 
Once the kelp in an area is gone, instead of dying off, the urchins go into a dormant state where they’ll survive for years, waiting for new food to arrive. 

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An urchin barren, which was formerly a kelp forest home to hundreds of marine animals.

While this is happening off the coasts off of Japan, Tasmania, Norway and Australia, California’s coasts are experiencing traumatic changes. 
In the last decade, more than 90% of bull kelp forests have died off in the north coast of California. Tristin McHugh, the Northern California Regional Manager for Reef Check California, a nonprofit working to save reefs and oceans, is researching what led to this. 
It’s hard to pinpoint one cause that has led to this current state, she said. But since the California Department of Fish and Wildlife started collecting data in 2008, California’s coast has experienced major losses.
In 2013, researchers watched urchin-eating sea stars die off for unknown reasons. “Losing sea stars in the north coast was kind of that last line of defense in terms of ecological structure,” McHugh told NationSwell. That’s because the purple urchin’s only other predator in the north was the sea otter, which was hunted to near extinction in the mid-1800s fur trade. 
Between El Niño storms and the warm blob hitting the coast, “by the end of 2016, the north coast was kind of torched,” she said. 
Purple urchins began to move inshore, feasting on the kelp forests that span 200 miles across Northern California’s coastline. Once the kelp forests, which are home to millions of underwater creatures, are gone, all that’s left is a desert-like urchin barren.
A few hundred miles south, areas on California’s coast have similar barrens. 
In 1998, Ford, having completed thousands of diving trips, jumped into the water and swam through a kelp forest for the first time. “I was blown away by how gorgeous they were,” he told NationSwell. “That is the simple and honest truth.”
Ford began studying the forests and quickly learned the forests were declining and falling apart. That research led to looking towards solutions with how to restore the forests.
Since the urchins can remain in a dormant state for years, the only way to bring back kelp is if the urchins are removed or destroyed.
“To move it from an urchin barren back to a kelp forest, you can either wait a long time or you can go out there and get to work,” Ford said. 
The startup company, Urchinomics, is also looking to get to work. Its solution: ranch them.
The company model is simple, collect these purple urchins, feed them until they’re at a marketable size and ship them off to consumers. The profits will then be invested back into restoring the kelp forests and collecting more urchins, deemed a restorative seafood model. 
“We try to turn this environmental challenge into an economical, ecological and social opportunity,” Denise MacDonald, the director of global brand marketing at Urchinomics, told NationSwell.
Crack open a healthy urchin, and in its center will be spilling out with orange gonads, called uni. It’s found in a variety of Japanese, French, Chilean, Spanish and Italian dishes. In those regions it’s an expensive delicacy — “sort of like the foie gras of the sea,” MacDonald said. In the rest of the world, it’s a potential new market. 
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The inside of a farmed urchin.

Brian Tsuyoshi Takeda, the CEO and founder of Urchinomics, worked with a Norwegian company that had successfully developed a feed for sea urchins. During that same period, Takeda watched the aftermath of the 2011 tsunami leave the coast of Japan, his home country, barren.
Those two things opened an opportunity to farm urchins and meet the market demand for the delicacy. 
“There’s a lot of opportunities for us to do good by bringing these kelp forests back and being part of the solution,” MacDonald said. 
Urchinomics is working with nonprofits to collect urchins. Urchinomics is in the final stages of launching its ranching facility in Newfoundland, Canada, which will transport urchins to the New York City market. It also has markets in Japan, Norway and other parts of Canada. In California, it’s working with divers to collect urchins for ranching.
Sam Briggs, a scientific diver, has collected urchins for over a decade. “I’ve witnessed firsthand what’s going on with the urchin problem,” he told NationSwell. So when Urchinomics hired his lab to collect purple urchins to farm, it was refreshing to be part of the solution, he said. 
“I like the idea of using these animals for a purpose,” he said. 
The Bay Foundation hires commercial sea urchin fishermen to go out and smash the animals. 
Smashing is the quickest approach. Previously, divers at the foundation would capture urchins and relocate them to other, non-populated areas, but due to expanding numbers, it’s no longer viable to move urchins to other areas. Ford’s team also looked at collecting urchins and composting them, but that proved to be greenhouse gas-intensive work. 
So for now, carefully trained divers enter the water and smash. Scientists research which areas to focus removal and monitor over the years. Since 2013, divers have spent 7,000 hours removing 3.6 million urchins across 46 acres. “There’s a tremendous amount of science before and after this all goes down,” Ford said. “They don’t just jump off the back of the boat and start swinging away like Paul Bunyan.”
So far their work has been successful. The kelp species in Southern California is a perennial, which means it is constantly reproducing and growing. Once nearly all the urchins have been removed, kelp rebounds in just a few months. 
Collected urchins from an urchin barren.

But in the north, where bull kelp is an annual species, that means there’s only one shot each year to reproduce. With all the changes to Northern California’s coast, conservationists are unsure if the kelp will grow back. 
“We’re just not equipped to deal with such rapid changes to our environment like this,” McHugh said. So Reef Check is launching a study to see if the kelp will regrow when urchins are removed and how many need to be removed for regrowth. 
Across the northern coast, groups like the Watermen’s Alliance are conducting large-scale removals of urchins, and NOYO Center is expanding public outreach.
Everyone from divers to scientists, fishermen to startup founders remain positive.
“There’s a wider audience that’s paying more attention to this kelp forest loss and not seeing it as the biologist’s problem but all of our problem,” McHugh said. “If the ocean agrees, I’m optimistic that the kelp will come.”
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