Foraging for Purple Sea Urchins Along California's Sonoma Coast

Writer and chef Joseph Ogilvy heads to the intertidal zone in search of the umami-rich delicacy that's mowing down California's kelp forests.UnsplashThis article is part of a series of stories about hunting, fishing, and foraging experiences across North America. Joseph Ogilvy is the author of Tin Can Coast, published in July 2026.It’s low tide, not long after dawn, and we’re about to disturb the tide pools of a small Sonoma cove in a hunt for sea urchin. Our group of would-be foragers are in Sea Ranch, a couple hours north of San Francisco, on the tough end of the California coast, where fog-pressed hills tumble into the Pacific. The tide pools of Pebble Beach are covered in shaggy mats and bundles of kelp, and the spots that aren’t blanketed in seaweed are a carnival of alien creatures: sea stars, anemones, crabs, abalone, a muddled parade of luminous colors and implausible body shapes.Nathan Maxwell Cann, a foraging guide with Flora & Fungi Adventures Tristen Lerman / Usal ProjectNathan Maxwell Cann, our guide, spectacled, moustachioed, and clad in a well-worn chore jacket and waterproof boots, talks the group through the principles and practice of sea urchin gathering. He tosses out the explanation of what we’re looking for with the easy, self-deprecating banter of a former bartender. For a long time he worked in restaurants in North California, but a few years ago he caught the tidal foraging bug and became a self-professed ‘kelp guy’ with a sideline in urchins.He shows us our prey. Out of the water, urchins look like curled-up hedgehogs, which is the root of their name in Spanish, Italian, and even English (many years ago our word urchin was used for the hedgehog). Their purple spikes project outward from a roughly hemispherical shell, known as a test. Most are somewhere between the size of a golf ball and a fist, and their only real feature is a malevolent-looking mouth armed with five overlapping teeth for grinding and shearing kelp.The purple sea urchins devastating California's kelp forests is one of the few seafoods that exist in abundance—or rather, overabundance. GettyIn the water, their flare of spines look like dark starbursts against the rock. At first you only see the big ones, but the longer you stare into the pools, the more urchins you will make out; what seemed shadows resolve themselves into potential pickings, far more than could possibly be taken by hand.There are huge number of purple sea urchins in this cove, and there are even larger numbers of purple sea urchins throughout California’s coast. Whole swathes of seafloor where kelp forests used to stand are now home to nothing but thousands of the prickly echinoderms, so-called urchin barrens. Similar barrens can be found in Alaska, Tasmania, New Zealand, South Africa, and beyond. Sea urchins have become one of the few seafoods that exist in abundance—or rather, overabundance.The idea of urchins as a pest wasn’t intuitive for me. When I first encountered them, they were luxuries, delicacies for the gourmand who'd graduated beyond oysters, requiring a great deal of time and discomfort, most of it mine: I was a commis chef in a London restaurant, and one of my duties was cleaning urchins. The restaurant served the roe raw in the shell or tossed with spaghettini; I was busy pulling shards of their spines out from underneath my fingernails.With California's sea otters hunted to the brink of extinction and sea stars struck down by an uncontrollable plague worsened by the state’s warming waters, the sea urchins have few natural predators left. Tristen Lerman / Usal ProjectIn the restaurant business, at least, urchins were still precious things. Only a few years later did I see the other side of their nature. After various twists and turns I found myself writing a book about the history of California and its ocean. The story followed the back-and-forth of human and marine life; how fishing and the sea shaped the state and how the state’s history shaped them in return. For most of the story, the urchin was a minor character compared to sea otters or sardines. In recent years, however, the unsuspecting urchin has moved to center stage: It’s not really coherent to call a brainless shellfish a villain, but within the drama of the intertidal zone, it’s not totally incorrect either.To put it bluntly, the urchins are out of control. They’re blindly mowing down kelp forests, leaving barrens in their place. And those kelp forests are—or were—marvels of diversity, providing a shelter for a wild array of ocean creatures from jeweled top sea snails to barrel-bodied harbor seals. The problem is the urchins' insatiable appetite for seaweed; unchecked, they will graze through the kelp stipes, dooming them to float away into the deep ocean.For most of California’s history, predators have kept urchin numbers down, but there aren’t many predators that can get past the wall of spikes and shell. The ones that really make a difference are sea stars and sea otters: Sea stars spew out their stomachs and envelop the urchins, dissolving the edible parts in their digestive juices then ejecting the empty shells. Otters just bash and bite their way through.The problem in Sonoma and the shore north of it, is that it’s been 150 years or more since a wild otter smashed open an urchin. In the early 19th century, California’s sea otters were hunted to the brink of extinction, the unparalleled softness and value of their fur drawing fur trappers all the way from Russia into California. Two centuries after the hunt, the sea otters’ range is still restricted to a couple hundred miles of the Central California coast.For a time the sea stars did double duty controlling the urchins, but in recent years they have been struck down by an uncontrollable plague, worsened by the state’s warming waters, called, quite literally, sea star wasting disease. The stars have grown lethargic and limp, with lesions spread across their bodies, their arms falling off or disintegrating. Their population has collapsed, allowing the urchins to chew kelp and multiply at their leisure.The real skill in urchin foraging lies in not falling over—the kelp-slicked rocks are slippery under the feet, and the ocean pulls at our ankles. Tristen Lerman / Usal ProjectSo, ecologically speaking, the job of our small group of foragers is to be the otters. The principles of urchin harvesting internalized, we ditch our shoes and move on to the practice, clambering around the rocky intertidal zone. Our little group is still shaking off our early morning bleariness while scattering over the rocks, bending over to peer closely into the tide pools. Gathering urchins has much the same feeling as mushroom picking or birdwatching (or indeed easter egg hunting). You quickly enter into a kind of focused flow state, punctuated by little jolts of childish joy as you spot what you're looking for. But compared to other forms of foraging, urchin gathering is easy as pie. None of my companions, mostly ocean-curious thirty-something Californians from the Bay and beyond, have been urchin foraging before, but their coolers and bags are soon brimming. The primary motivation of my fellow foragers is split: half are most excited by the prospect of eating our catch, the other half by the experience of going out and catching it.Once your eye settles on the color and shape of them, they’re everywhere. Picking the urchins up from their niches just takes a little clasp and a wiggle with a pair of tongs. The real skill in urchin foraging lies in not falling over—the kelp-slicked rocks are slippery under the feet, and the ocean pulls at our ankles, while the busy strangeness of the tide pool creatures makes it easy to get distracted.As Cann puts it, urchin gathering is really just “a reason for being out in the tide pools.” Tristen Lerman / Usal ProjectAs my net bag begins bulging with spines, I find myself more and more absorbed with what John Steinbeck called the ‘hurrying, fighting, feeding, breeding animals of the tide pools’; the scuttling of a hermit crab fleeing from my shadow, the respiration holes of an algae-camouflaged abalone peeking from a crevice, the waft and flicker of an anemone’s tentacles. The coos and camera clicks of my fellow foragers suggest they are just as absorbed. Which is kind of the point. As Cann puts it, the urchin gathering is really just “a reason for being out in the tide pools.” The constraint of the task encourages a deeper looking, and gives us, part of a society suspicious of aimless activity, an excuse to mess around and explore a strange world.And besides, they taste good. Back on dry ground, we each grab a stout pair of kitchen shears and crunch a rough circle out the top of an urchin, scooping and tossing its muddy, briny viscera, rinsing the creature in a bucket of seawater and using a mussel shell to spoon out the five golden tongues of roe, arranged in a star shape. The roe is rich and buttery, starting off savory and briny, then mellowing into a higher note of sweetness. It’s bracing stuff, especially at 8:15 in the morning. It tastes powerfully of place. Cann explains that the umami savor comes directly from the kelp it feeds on. No wonder that, at the Sea Ranch Lodge just down the coast from our expedition, the head chef Ryan Seal makes a sea urchin zabaglione as the base for a carbonara, introducing urchin-hesitant guests to the delicacy while showcasing an intrinsically Sonoman flavor.Sea Ranch Lodge chef Ryan Seal uses the local sea urchins to make an “uni carbonara” with squid ink chimaera pasta, pancetta, and furikake. John Burgess / The Press DemocratStill on the shore, we stand around in a group chatting while we open more urchins and swallow the meat inside. Even with the appeals and distractions of the intertidal world and a few early morning tongues of uni, our bags are still overflowing. But our gathering has barely made a dent in the cove’s urchin numbers. As substitute otters we have come up short; the real thing can eat dozens of urchins in a day.And still, uni foraging workshops are increasingly common all over Northern California, adding to the many beachcombers who pick urchin on their own. The urchins are still dominating the coast though. From an ecosystem perspective, our efforts are little more than “a drop in the bucket”, as Cann acknowledges. Restoring the kelp forests will require a more forceful campaign. The Giant Giant Kelp Restoration Project in Monterey has an enormous submarine vacuum to suck urchins from the barrens. In Northern California, scuba divers just crush them with hammers. Entrepreneurs all over California and the West Coast have begun ranching operations, gathering the often underweight urchins from the barrens and fattening them up on sustainably harvested kelp before selling them to restaurants. Another company in Mendocino, Marblis, is compacting the shells into what they call urchinite, pitched as a substitute for marble countertops.Our morning workshop of tongs and kitchen shears, by contrast, is a symbolic gesture. By mid-morning, my fellow foragers and I will be heading back home with fond memories and a few meals worth of seafood delicacies. The urchins will continue to chomp their way through the kelp forests of Sea Ranch.Kelp forests—which simultaneously serve as a carbon sink, wildlife habitat, and protection against erosion—are vital to Sonoma's coastal ecosystem. GettyBefore we split to find the coffee we both need, Cann and I stand in the parking lot and talk through what the urchin gathering is really about, given that we’re not singlehandedly saving the kelp. It’s a form of education or consciousness-raising for sure. There’s nothing like feeling the kelp between your toes or swallowing urchin roe just minutes after it has left the water to make the stakes of ocean conservation feel close to home. You can make the case that activities like this develop virtues of generosity and curiosity in ourselves; my fellow foragers filter out of the car park smiling and carrying dripping containers; they tell Cann what they’ll do with their haul, who they’ll invite for dinner or share their newfound knowledge with.Steinbeck advised his readers to look “from the tide pool to the stars and back to the tide pool again.” Maybe that’s what the foraging is really about. The focus on one small creature opens you up to its myriad connections to everything else. At the same time, it puts you in that web, gives you a visceral way to feel the relationship between yourself, the urchin, and the rest of the tide pool world; you can quite literally taste the kelp forest in the uni. I’ve seen the sea urchin as a pest and a delicacy, an ecosystem villain and a precious treat worth getting splinters for. But it was only when I planted my feet in its rock pool home and plucked one from the water and threw back its roe that I really saw it in its place.