Oyster Farming in Morro Bay

Oyster Farming in Morro Bay1

The tidal flats in Morro Bay estuary make a welcome home for oysters planted for harvest.  Oyster farmers have been cultivating them here since at least 1932 and continue to do so  today but there is evidence in middens that domestic oysters made part of the food supply for  native American tribes for hundreds of years. Oysters are a significant part of the story of Morro Bay. 

Growing Oysters for the 49ers and Beyond 

The huge influx of Eastern immigrants during the gold rush during and after 1849 made  entrepreneurs try to create a new food source for hungry miners. Many of the immigrants were  used to a diet that featured oysters—the mollusks were a mainstay of diets of all classes on the  East Coast—so there was a ready market. 

Farmers tried to plant local oysters (ostrea lurida) in San Francisco Bay beginning in 1851,  especially along the south and west sides of the Bay. These shallow beds were fenced to  prevent predation from bat rays and were somewhat successful locally. The new State  recognized the value of oyster farming with the Oyster Act of 1851 which gave access to state owned tidelands simply by driving in stakes on a claim. 

Farmers were experimenting with locations, methods and oyster species. By the late 1880’s  they had found that imported Eastern oysters (crassostrea virginica) grew faster and larger than  the local variety and began to switch so that between 1890 and 1930 the Eastern variety was  very dominant in the market. 

Beginning in 1905, farmers began experimenting with Pacific oysters (from Japan) in several  locations on the West Coast and found that they were even easier to grow. The Pacific oyster  (crassostrea gigas) became the dominant species after 1930 and remains so today. 

Farming is shaped by the life cycle of the oyster 

Pacific oysters (and the imported Eastern oysters before them) do not reproduce easily in  California waters and that means they need to be imported for oyster farmers. Like any other  crop, seed (tiny, immature oysters grown from larvae called ‘spat’) is what is imported. For  many years, most of the Pacific seed was from Matsushima Bay in Japan. This was  supplemented by the domestic set in Willapa Bay, Washington and later from other locations  as techniques improved.  

Harvesting, transporting, and planting oyster seed is tricky. The spat (larvae) that naturally  occur in the water where oysters mate will attach to a hard surface where they can begin to  grow (oyster shells and other hard surfaces make good attachment places). Seed producers  (as in Japan) used shells to get the spat to attach and grow to the point they could be  transported. The Japanese seed-rich shells were packed into cases and covered with wet  grass mats that would not expose the seed to air. 

The seed that survived the journey to California oyster beds had to be planted carefully to  protect the immature oysters and allow them to be harvested when fully grown. The Pacific

  1 We rely heavily on the historical evidence about oyster farming in California through 1958 1 from Elinore M. Barrett, The California Oyster Industry. Fish Bulletin 123, CA Department of  Fish and Game, Sacramento: 1963. We will not cite the many references to this material—it has  been essential.

oyster will take about 2 to 3 years to mature from seed, growing on the shell or other surface  they attached to.  

Oyster farmers have experimented with a lot of creative ways to plant oyster seed so that the  young oysters would be able to filter nutrient out of the passing flow of water without being  exposed to various hazards. A lot of predators, including human poachers, love oysters. Other  natural threats in the shallow water they live in include bacteria, silt, sludge, poisons and  pollutants. Sometimes the oysters carry a bacteria that is harmless to them but very dangerous  to humans. 

Rain water flowing into Morro Bay estuary can stop the harvest of oysters. State regulations  require a pause after heavy rainfall to test for bacteria and other pollutants that might be  harmful to anyone who eats the oysters. As Neal Maloney, owner of Morro Bay Oyster Co. said,  “You can say that we’re the only farmers who don’t like rain” (LA Times, February 2, 2023). 

Oyster Farming in Morro Bay through WW2 

Raising oysters is a risky business, like all farming is. You can see that in the wide variation in  the number of pounds of oysters harvested in Morro Bay over time. 

Two of the most prominent experts on oyster farming, Paul Bonnot and HC McMillin were the  first to plant imported Pacific oyster seed on the Morro Bay estuary tidal flats in 1932. Another  pioneer was FB Tolman who was a Stanford geologist. This effort yielded very little until 1938  when 3,100 pounds were harvested. Other farmers, like LE Osborne, staked claims and started  planting, too. By 1938, the San Luis Obispo Telegram-Tribune (March 17, 1938) wrote 

A steadily growing industry at Morro Bay shows promise of becoming one of the main  commercial ventures of San Luis Obispo County, the growing of oysters. 

In April 1936 a few boxes of oyster seeds were planted in Morro Bay… 

By 1940, the bay produced 15,700 pounds and during the war years through 1945 the harvest  exploded to a maximum in 1943 of 60,500 pounds, which was almost 52% of the entire crop in  California that year (data from Barrett, 1963). The biggest reason was probably the market:  Several large military training bases were in San Luis Obispo County and soldiers have to eat! 

Bonnot and McMillin were unable to get a sufficient supply of seed because the Japanese  source was unavailable during the war and labor was in short supply, too. They stopped  planting in 1948. The life cycle of oysters predicted the near future of the crop in Morro Bay:  the harvest in 1951 was just 200 pounds. Bonnot and McMillin sold out.  

But as early as 1950 other farmers came in to take an allotment in the bay and start over. Early  companies included Browns Oyster Farms and the Leage family’s El Morro Oyster Company.  Once they began harvesting again, these companies made Morro Bay a top-producing area  again, taking over 190,000 pounds of oysters in 1958. By this time, almost 100% of the oysters  planted in California were Pacific (c. gigas) raised from seed imported from Japan. 

The Modern Era of Oyster Farming in Morro Bay 

The Leage family’s El Morro Oyster Company provides a good starting point for watching the  postwar evolution of oyster farming in Morro Bay. An emblem of the company’s success is 

found in the modern packing plant it built on the edge of the estuary south of Tidelands Park.  The building still stands as a family residence and is easily viewed from the water. 

In 1958, the same year the packing plant was built, Orval Leage took a shipment of seed from  Japan that would be planted on 950 acres in the El Morro Oyster Company allotment on the  tidal flats. He explained that the seed had been ‘hardened’ in Japan by brief exposures to air to  encourage the oysters to form a stronger closure of their shells. 16,000 seeds were packed in  in each crate and kept moist for the trip to California. The seed had to be planted as soon as  the right tides happened and that meant working at night in this case (SLO Telegram-Tribune, 4  March 1958). 

Ralph Johnson was an experienced oyster man who farmed oysters beginning in 1939. He  owned parts of farms in Humboldt Bay near Eureka and in Drakes Bay near San Francisco. He  bought the El Morro Oyster Company tideland allotment in March 1968 and continued the  established operation doing business as the Morro Bay Oyster Company. In December of that  year he and his workers spent the Christmas holiday harvesting and packing oysters ordered  by Safeway. (SLO Telegram-Tribune, 23 December 1968). 

Johnson continued to farm oysters for a number of years, but evidently let his allotment go  fallow at some point in the 70s. The headline of a September 1983 article in the SLO Telegram Tribune reads “Oyster production returns to the bay” which marks the beginning of the  Qualman Oyster Company in Morro Bay. Larry Qualman and his son John of Coos Bay,  Oregon, purchased the rights to the allotment with plans to plant oysters in both November  and the following spring. Their intention was to eventually have enough oysters planted in a  staggered sequence in order to harvest almost continuously. 

The Qualmans brought new techniques to the estuary. An important change was the ability to  grow their own seed rather than rely on importing from Japan or Willapa Bay in Washington. A  technique to facilitate this was “put together at Oregon State University using Sea Grant  money,” a Federal program. In addition, the Qualmans planted seed attached to sticks rather  than shells or another hard surface. The big advantage was that sticks could be pulled up  whole during harvest and got to shore more quickly for processing (SLO Telegram-Tribune, 16  September 1983). 

The Qualmans’ affection for Morro Bay ran headlong into pollution caused by sewage from  people living around the bay. Both the Qualmans and their neighbor farmer Ralph Williams,  who farmed a little 15 acre plot, struggled to fight the pollution. The Qualmans sued to force  Morro Bay to sanitize the water while Williams transported his harvestable oysters to a location  in Cayucos to clean them (SLO Telegram-Tribune, 25 February 1986). 

In the end, the Qualmans lasted only five years in Morro Bay, selling out because the bay was  too polluted—and therefore risky—to attract new investors. Ralph Williams purchased the  much larger Qualman allotment to add to the few acres he already had, believing that new  water treatment methods in Morro Bay would eliminate most of the pollution.  

Like others before him, he pioneered new ways to cultivate oysters. Williams used a nursery in  Oregon to collect and nurture the spat and then when the spat had matured enough used his  imported Philippine shells to attach the seeds. He then attached the shells with seed to metal  rods that he would drive into the bay floor keeping the shells off the bottom so crabs could not  reach them. The small distances between rods meant the bat rays could not swim between  them thereby removing one dangerous predator. Williams believed the sharp edges of the  imported Philippine shells of the variety he used to attach seeds kept the sea otters away. He  started on a burst of confidence (SLO Telegram-Tribune, 5 April 1988).

By 1994, the Williams Shellfish Farms was the only oyster farm on Morro Bay estuary and was  the third or fourth largest oyster producer in California. Williams farmed about 275 of the total  800 acres in his allotment for planting oysters which yielded between 800,000 and a million  oysters in 1993. His techniques continued to change but his persistence and patience helped  him produce high quality oysters. Williams was a man who loved to go to work (SLO Telegram Tribune, 20 January 1994).