OYSTERS! How They Got Here and Why We Hope They Stay

Few foods are as divisive as the humble oyster: You either love them or you haven’t tasted a good one yet. Regardless of where you stand, it seems that the mollusks are having their moment, and if you’re a Bay Area–based bivalve enthusiast, you can eat some of the best in the world within hours of when they’re harvested. However, be warned: You may find lengthy queues at your local oyster bars, which are dwarfed only by the weekend crowds at nearby oyster farms.

As more people become oyster aficionados and local oyster farms expand their operations, the good news is that, unlike with most monoculture farming, oyster cultivation happens to be really good for the environment. To learn more while enjoying some of the world’s best oysters, I decided to head to Tomales Bay. Oysters farmed here are highly sought after and for good reason: They are briny, sweet, crisp and clean, the pinnacle of oyster-ness. Just as vineyard terroir is crucial to wine grapes, the terroir of an oyster bed plays a role in the taste and texture of its inhabitants.

Tomales Bay gets a lot of help from Bodega Canyon, a 6,000-foot-deep underwater canyon just west of the Bay Area. The canyon functions like a compost heap, with strong currents depositing massive amounts of organic material into the bay. This dependable upwelling of nutrients ensures that Tomales Bay sea critters are very well fed, and the Pacific’s cold waters ensure a tasty harvest year-round.

Oyster Farms of Tomales Bay

On a midweek stop at Hog Island Oyster Company, I was lucky enough to join a farm tour led by George Curth, who has been with Hog Island since 1999. Founded in 1983 and still operated by the two founding families, the PR-savvy producer has been instrumental in elevating the status of Tomales Bay oysters throughout the country. Hog Island works hard to ensure that the more than 85,000 oysters they ship to restaurants and serve at the farm every week meet the high standards for which they are famous.

Curth described what sets oyster farming apart from other more intensive forms of aquaculture such as fish farming: “All we do is make sure our oysters are in the way of the flow of food.”

Curth explains that every oyster, whether wild or farmed, begins its life in warming waters as oyster eggs and sperm join to become larva that attach to shell fragments. Wild oysters grow in groups and stay in one place their entire lives. Their farmed counterparts, on the other hand, stay in a hatchery for a few weeks and then are placed in mesh cylinders and moved to a nursery in the bay waters, where they are strategically positioned to take full advantage of the tidal energy (wind and waves). Here they get rocked around, gently tumbling them against each other in a way that breaks off the delicate new growth along the edges of their shells. The oysters respond by forming a harder shell with a deeper cup. Curth explains that, “The oysters are exercising all the time and building a strong muscle.”

When they get a bit larger, the oysters are transferred into larger mesh bags, placed on racks and suspended above the bay bottom. There they gobble up all the best plankton and nutrients while still being exposed to air during low tide. “They get used to being out of the water for a while. This helps them to withstand transport, which will give them a longer shelf life.” They will stay on the racks for the next year or two, until they are ready to go to market.

Once the oysters have reached their ideal size, they are brought to shore to be inspected and sorted by size. Oysters that make the cut are counted, re-bagged and placed into special saltwater tanks for 24 hours. Curth tells us that “this gives the oysters a chance to clean out … we also gradually lower the temperature to 40°F, which slows down their metabolism.”

Bags intended for transport are labeled with tracking tags containing data of where and when the oysters were harvested and when they were delivered. If you’re served a bad oyster at a restaurant, Curth suggests that you ask to see the tag. “It’s your right as a consumer,” he says.

Curth wraps up tours with a lesson in shucking and a tasting. He insists on a glove and recommends the Dexter Russell #22 knife.

Another stop on my tour was Tomales Bay Oyster Company (TBOC). Periodically changing ownership since it was founded in 1909, TBOC remains the oldest consistently operating commercial oyster farm on the bay, and offers both the Kumamoto and the unique Golden Nugget—a tumbled oyster with a deep-cupped shell and a creamy texture unlike anything I’ve ever tasted. On a spring visit, staffer Gina Warren explained that the unique texture was due in part to the fact that the oysters were getting ready to spawn as the water warmed up.

Open every day of the year for retail sales and shuck-your-own, TBOC is well prepared for the weekend crowds with dozens of grills and picnic tables. Retail manager Sean O’Brien warns that they get busy on the weekends so parties of 10 or more are encouraged to make a reservation.

Asked about the recent, and extremely contentious, shutting down of historic Drake’s Bay Oyster Farm by the National Park Service, he says, “losing Drake’s Bay has really impacted us. There is less supply and more demand as oysters have gotten more popular. People enjoy the whole experience—losing Drake’s has cut down on the opportunity for people to enjoy themselves. We need more activities for people to do as a family … it’s all about the pursuit of happiness…”

Just up the road, hungry daytrippers can continue pursuing their happiness at TBOC outpost the Marshall Store, which offers a raw bar in addition to a menu that includes both barbecued and house-smoked oysters as well as chowder and artisan sandwiches, all of which can be enjoyed waterfront (it’s especially dreamy at sunset) and washed down with some wine or a cold beer.

Like TBOC, Hog Island’s location in Marshall gets packed on the weekends. You can either shuck your own or enjoy raw or barbecued oysters from their bar with some cold beer and local cheese, but there are no guarantees of elbow room. The most desirable tables, located closer to the water and outfitted with charcoal grills, are available by reservation, and book up months in advance. During the week, the bar is closed but the farm is open to the public for shuck-your-own and you can reserve an intimate tour and tasting.

Hog Island also operates oyster bars in both San Francisco’s Ferry Building and the Oxbow Public Market in Napa Valley, sells on Sundays at the Ferry Plaza farmers market and supplies to some of the finest restaurants in the Bay Area including Zuni Cafe and Chez Panisse (Alice Waters also happens to be on Hog Island’s board) and throughout the country.

A Short History of Oyster Cultivation

Human appetite for these plump little delicacies has a storied and noble history. There is ample evidence that humans have been slurping down oysters since prehistoric times, with piles of discarded shells, or middens, discovered at archaeological sites in both Northern Europe and North America dating back over 4,000 years.

The Greeks began to study oysters scientifically in the fourth century BCE, and imbued them with spiritual and romantic importance. Aphrodite, the goddess of love and beauty, was said to have born from an oyster shell, elevating its status as an aphrodisiac. Also, the Greeks and Romans are credited with pioneering oyster cultivation, with some of those innovations still in use today by modern oyster farms. Olympia oysters, the only oyster species native to North America’s West Coast, sustained California’s indigenous coastal populations for millennia. But manifest destiny and the gold rush brought devastation to these bivalves and many other native species, and within a relatively short time, overfishing nearly drove California’s native Olympias to extinction. However, the Olympias were soon transplanted from the Pacific Northwest and Mexico as commercial oyster farming in the Bay Area was born, and the popularity of the briny bivalves soon led to the advent of oyster pirates, who raided the corporate oyster beds at night and sold their booty at a discount to appreciative crowds in Oakland’s markets in the morning. Perhaps the best known of these swashbucklers was Jack London, who mentions oyster piracy in his autobiography and several of his other works.

The march of industrialization and population growth eventually led to San Francisco Bay becoming too polluted to sustain oyster aquaculture and the last commercial oysters were harvested from the Bay in 1939. Fortunately, oyster farming continued in other parts of California, including Morro Bay, Drake’s Estuary and Tomales Bay, which became the new center of the state’s oyster industry.

More on Oyster Sustainability

Oyster reefs—also called beds—provide shelter and habitat for many other species. Each oyster can filter upward of 50 gallons of water per day and provide a critical service by removing sediment and other nutrients including nitrogen from farm fertilizer runoff. Too much nitrogen results in “algae bloom,” which, in turn, can lead to hypoxia or oxygen depletion that transforms an otherwise healthy body of water into a dead zone where nothing survives. These dead zones are not only ecologically devastating, but can prove extremely costly to local economies that rely on a dependable catch.

As industrious as they may be, oyster reefs are unfortunately not immune to the effects of climate change. Increased levels of carbon dioxide are altering water chemistry and increasing ocean acidity, and warmer water temperatures threaten the safety and ability to harvest year-round.

Thankfully, researchers at UC Davis’s Bodega Marine Lab are on it. One group called BOAR (Bodega Ocean Acidification Research) is working closely with Hog Island Oyster Company to monitor ocean acidification and hypoxia.

I spoke with the lab’s James Moore, who works for the California Department of Fish and Wildlife helping to regulate importations of oyster seed and transfers of oysters throughout the state, and who conducts disease surveillance on oyster populations. Moore says that oyster farming, as currently practiced in California, is sustainable. His suggestion as to what we consumers can do? “Oyster lovers can practice sustainability by asking their suppliers to provide local oysters, rather than oysters that are trucked down from Washington State. Economies of scale often make out-of-state product cheaper, but local product has a lower carbon footprint and is fresher, well worth a few cents more.” If you’re the curious type, the Bodega Marine Lab is open to the public for tours on most Fridays between 2 and 4pm.