In Canada, the main species of shellfish farmed commercially are clams, geoducks, mussels, oysters and scallops.
The Manila Clam (Tapes philippinarum) has been harvested in British Columbia since the 1970s and has been farmed since 1985. It is known for its firm texture and sweet flavour.
Manila Clams were accidentally introduced to the Pacific Northwest in the 1930s when seed was inadvertently included with Pacific Oyster seed imported from Japan. The first mature specimens were found in Ladysmith in 1936 and, today, the Manila Clam lives along much of British Columbia’s coastline – as far north as Bella Bella. It is not an indigenous species.
Manila Clams do not burrow as deeply as native species, such as Butter Clams (Saxidomus giganteus) and Littleneck Clams (Protothaca staminea) and they occupy an area higher in the intertidal zone. As a result, they co-exist well with the indigenous clam species.
The geoduck (pronounced gooey duck) clam is the largest burrowing clam in its natural range throughout Alaska, British Columbia and Washington. With an average weight of 1 kg (2.2 pounds) and an average shell length of 195 mm (7.75 inches), the geoduck’s shell is not capable of encompassing the body of the animal.
Historically, geoducks (Panope Abrupta) were harvested for food in the Pacific Northwest by the Aboriginal peoples. The clams currently support a prosperous commercial fishery in Alaska, British Columbia, and Washington.
The first significant step to develop a geoduck aquaculture industry in BC was taken in 1995 when a five-year initiative was spearheaded by stakeholders, including investors and researchers. Since then, the technology for geoduck farming in BC has been refined and developed and farming of the geoduck is poised to move forward into commercial development and expansion.
Both the Blue Mussel (M. edulis) and the Gallo Mussel (M. Galloprovincialis) are farmed in British Columbia. The Blue Mussel is renowned for its rich, sweet taste and its dark blue shell.
Mussels have traditionally been more of a problem to shellfish growers than a potential farmed animal. In North America, we began farming mussels in the 1970s and it is now a substantial industry in the northeast United States and Atlantic Canada where M. edulis is the main species grown. Efforts to farm British Columbia’s native Mytilus trosullus have been thwarted by duck predation and natural summer mortality.
The Pacific Oyster (Crassostrea gigas (Thunberg)) is the species most widely farmed in British Columbia. Its meat has a mild, sweet flavour and a firm texture.
The Pacific Oyster originated in Japan; several oysters were brought to BC around 1913, but most of the seed was imported from Japan between 1930 and World War II. The Pacific Oyster established itself in several areas, including Ladysmith and Pendrell Sound. In 1950, Pendrell Sound was set aside as a reserve to protect breeding Pacific Oyster stocks. Today, Pendrell Sound and Pipestem Inlet are still widely used by growers to collect oyster seed (spat).
The native Olympia Oyster (Ostrea lurida), British Columbia’s only native oyster, was nearly wiped out a century ago. Until the late 1800s, Olympia Oysters supported sustenance and commercial fisheries and occupied thousands of acres of productive, diverse habitat. Olympia Oysters were listed as a species of special concern in 2003 and are blue-listed by the Province of British Columbia. Our native Olympia Oyster is a smaller, slower-growing oyster than the Pacific Oyster and it is not suited for farming, except for a limited specialty market.
The Japanese Scallop (Patinopecten yessoensis) is the main species farmed in British Columbia. It has a sweet flavour and a firm, lean texture.
There are several species of native wild scallops in British Columbia: the Weathervane Scallop (Patinopecten caurinus), Rock Scallop (Crassadoma gigantea), Pink Scallop (Chlamys rubida) and the Spiny Scallop (Chlamys hastata). The population of these species is insufficient to support a commercial fishery or seed collection for farming. Although the potential for hatchery production for these species exists, growth rates of these native species are slow and present a barrier to feasible farming operations.
Japanese Scallop seed is hatchery produced for grow-out operations in Georgia Strait and the west coast of Vancouver Island. There is also a hybrid of the Weathervane and Japanese scallops that is farmed in British Columbia. – BCSGA