Saving California's Kelp Forest May Depend On Eating Purple Sea Urchins : The Salt Purple sea urchins are devouring the kelp forest off California's coast. To help the forest survive, researchers are trying to make these urchins a delicacy on menus at seafood restaurants.

Saving California's Kelp Forest May Depend On Eating Purple Sea Urchins

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A group of scientists is hoping more restaurants will put purple sea urchin on their menus. The urchins feed on kelp. And if more of us feed on the urchins, the scientists say we could help California's shrinking kelp forests. From member station KAZU, Erika Mahoney has the story.

ERIKA MAHONEY, BYLINE: Just off the Monterey Peninsula, a boat sways in the ocean. Three divers get ready. They're students from Moss Landing Marine Laboratories. The assignment - count purple sea urchins.

SHELBY PENN: Catch you on the flip side.


MAHONEY: Their professor Dr. Luke Gardner waits on deck. He expects they'll find plenty of urchins, and that's not a good thing.

LUKE GARDNER: What they do is they just eat everything in sight.

MAHONEY: These spiny creatures are mowing down California's kelp forests. Kelp is a vital part of the ecosystem. It provides food and shelter for numerous animals, including abalone and rockfish. The problem began about five years ago when purple sea urchin populations skyrocketed.

GARDNER: So with the increase in purple sea urchins, what we've seen is a dramatic reduction in kelp cover, primarily in Northern California.

MAHONEY: Urchin barrens are areas that used to be full of kelp and are now full of urchins. A diver takes video with a GoPro camera. It shows rocks covered in spiny ball-shaped creatures that can fit in the palm of your hand. The divers surface holding some of them.

GARDNER: They've just got a bunch of spines, you know, bright colors.

MAHONEY: What's inside is the part we eat, the uni. Commercial divers have been harvesting urchins in California for decades, primarily red sea urchin because they're bigger. Gardner says we should be eating more of the purple ones.

GARDNER: The problem with these guys is that when you open them up, there's nothing in there.

MAHONEY: Since they've eaten up their food supply, they're basically skeletons. Enter aquaculture, or the farming of aquatic organisms. The Moss Landing Marine Lab Aquaculture Center is outdoors and next to the ocean. Here, graduate student Katie Neylan helped run an experiment. The goal - make these urchins valuable by turning them into a delicacy. Students removed 500 purple sea urchins from the ocean and transplanted them here into big, blue tanks.

KATIE NEYLAN: We had red algae that we fed them called ogo, or Gracilaria pacifica. We fed them kelp, which is just giant kelp - Macrocystis pyrifera.

MAHONEY: The ones eating ogo reached market size faster, showing they're better off eating something other than kelp.

Time for the taste test. The class crowds into the kitchen of Michelin-star restaurant Aubergine in Carmel-by-the-Sea. Here, executive chef Justin Cogley serves uni from around the world. He uses tweezers to open up the purple urchins, revealing the orange uni inside. His favorite is the ogo-fed.

JUSTIN COGLEY: Honestly, it's rich and buttery, you know? I think this one might be a touch - taste a little bit cleaner, honestly.

MAHONEY: The ogo?


MAHONEY: His conclusion - he'd serve it. Cogley prepares the uni on a fried potato with a sweet soy glaze for everyone to try.

NEYLAN: Cheers, everybody.

MAHONEY: It's a tasty end to the project, but this could be just the beginning. A company called Urchinomics has been selling their ranched urchins in Japan. Now they're working to secure a site in California, all to save the state's dwindling kelp forest and help the thousands of animals that depend on it.

For NPR News, I'm Erica Mahoney in Monterey, Calif.


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