Aquaculture in the Sanctuary

Aquaculture has a long and rich history along the central California coast within what are now the boundaries of the Monterey Bay National Marine Sanctuary. Beginning in the mid-nineteenth century, Chinese immigrants working around the Monterey Peninsula and southwards to Cambria burned intertidal areas to expose rocks on which they could cultivate a variety of red algal species. The algae were then harvested, dried, and used as food. This practice carried on into the mid-twentieth century.

Market abalone being fed kelp. photo David Ebert

The latter part of the twentieth century saw a number of different species cultivated with varying degrees of success. Species as diverse as abalone, algae, lobsters, oysters, sea hares, steelhead trout, salmon, and shrimp have been grown in and around the Sanctuary. Oysters were cultivated in Elkhorn Slough and at Pigeon Point during the 1960s and 1970s, but poor water quality eventually curtailed both operations. SilverKing Oceanic Farms in Davenport attempted salmon ranching from the late 1960s up until the mid-1980s. The idea of releasing salmon and waiting two to three years for their return seemed to work, as many fish did return. However, as the salmon were returning most were either caught by fishermen or devoured by hungry sea lions prior to reaching their final destination. The 1960s and 1970s also saw attempts to culture lobster on Cannery Row and abalone at Pigeon Point and on Cannery Row.

Currently at least six aquaculture companies operate within the Sanctuary, culturing such diverse species as abalone, algae, steelhead, salmon, and shrimp. A brief review of these operations follows.

There are three abalone farms operating within the Sanctuary. Abalone are a unique animal for cultivating, because every part of the animal can be sold at market. In addition to the meat, the shells can be sold for jewelry, ornaments, and souvenirs. The viscera cannbe processed for fish food for the aquarium trade or sold as bait. Finally, pearls can be cultured from the abalone. This product holds the most exciting potential, as a single gem-quality pearl may bring fifty times the price that the same animal would garner if sold without a pearl.

Checking abalone in the nursery. photo David Ebert

US Abalone, located in Davenport, cultures abalone in land-based tanks referred to as raceways. It has been in operation for more than twelve years and is one of the largest producers of cultured abalone pearls in the world. Two other farms currently produce abalone in the Sanctuary: Monterey Abalone Company and Pacific Abalone Farms are located in Monterey and grow abalone in habitats suspended in the ocean. Theirnprincipal product is live red abalone, mostnof which is sold locally.

Reed Mariculture, founded in 1995, is the leading marine microalgae producer in the world. The company’s original concept was to produce bivalve shellfish, from seed to adult, fed only on algae raised at the site. In 1998 its product focus shifted from shellfish to the production of commercial microalgae feed for aquaculture. Marine microalgae is used in finfish, shrimp, and shellfish hatcheries as either a direct or indirect larviculture feed. The “Instant Algae” brand of algae concentratesnis used to replace or supplement live algae grown in hatcheries, resulting in lower costs, increased production, and reduced risk. Reed produces a wide variety of algae species, including Nannochloropsis, Tetraselmis, Isochrysis, Chaetoceros, Thalassiosira weissflogii, Thalassiosira pseudonana, and Pavlova. Reed’s primary customer base is in the Mediterranean, Europe, and Asia, with smaller markets in North and South America.

Monterey Bay Salmon and Trout Project is an organization whose efforts are focused on three programs. The main focus is to enhance salmon populations and to reduce pressure on wild fish populations by allowing fishermen to target hatchery fish. Fall run chinook or king salmon smolts are obtained from state hatcheries and acclimated in net pens in Monterey and Santa Cruz harbors. Up to 300,000 fish may be released per year. There are no wild runs of fall chinook in this area because the streams are dry at the time of year they are genetically programmed to return. The fish do not survive beyond the fall and therefore do not interfere with any other runs of anadromous fish. In good years, 6 to 10 percent of the fish will return to the area as adults.

Steelhead swimming upstream. photo Courtesy of Pacific Northwest National Laboratory.

Another program involves the capture, spawning, and release of steelhead and coho salmon (both endangered species) from their Davenport hatchery. Each winter steelhead are caught at a station on the San Lorenzo River, with fifteen to thirty adult fish taken to the hatchery, spawned, and then returned to the river. Coho, or silver salmon, are very scarce, and the only viable run of these fish into the Sanctuary waters is from Scott Creek. Unfortunately, project members report no mating pairs of coho for the last two winters. They fear that unless coho are able to return and spawn this winter, the run may be lost.

The third program involves setting up chilled aquaria in about 140 classrooms in central coast communities. Project members put steelhead eggs in the aquaria, and students are able to observe the hatching and development of the fry and then release them into local creeks. The hope is to foster a sense of stewardship and an awareness of the environment in the students.

As we have seen, the products of aquaculture may be used to enhance wild populations, as food, or for other products such as jewelry. Despite the long and varied history of the aquaculture industry in the Sanctuary, its current production is relatively small when compared to the size of the area and the population living along the Sanctuary’s shores. The U.S. seafood trade deficit was a record $7.1 billion in 2000, up 19 percent over 1999. With wild fisheries under pressure, further growth in seafood consumption will depend on the success of aquaculture, both locally and globally.

David A. Ebert(1) and Arthur Seavey(2)
(1)US Abalone
(2)Monterey Abalone Company