Site Created
and Maintained By:
CTP Logo
© 2010



Pacific Oyster   Pacific Oyster

  Scientific Name:

Crassostrea gigas

 Common Name:

Pacific Oyster (also: Pacific cupped oyster)

 Native Range:

Japan, China, Korea, Taiwan, Hong Kong

 Established Range:

C. gigas is established in Europe, New Zealand, Australia, and on both North American coasts.

 Established in Rhode Island?

No. Future introductions are unlikely, as the aquaculture industry in RI is highly regulated, and it is illegal to conduct any aquaculture activities that are likely to have an adverse effect on adjacent marine life or the indigenous fisheries of the state (RIGL 20-10-5).

 Method of Introduction:



C. gigas prefers to live on hard surfaces in sheltered waters within the intertidal zone. This hardy shellfish can survive in salinities between 10 and 32 parts per thousand, and temperatures of -1 to 35° Celcius.


C. gigas is a filter feeder that eats plankton and detritus.

 Average Life Span:

Unharvested C. gigas can live up to 30 years.


C. gigas is hermaphroditic and reproduces sexually via broadcast spawning.


C. gigas is an extremely hardy, disease-resistant species that has been known to out compete native species of shellfish for food and space. Additionally, because C. gigas is very resistant to becoming ill, it can carry diseases that can negatively affect other species, but but not its own. Additionally,C. gigas can outcompete and exclude native species of oysters.


Scientists have been experimenting with using parasites, sponges, and mudworms as biological controls. Additionally, producing sterile triploid C. gigas and introducing them to established Pacific oyster colonies can help to prevent their spread.


 Works Cited:

Helm, M.M. 2006. Crassostrea gigas. Cultured Aquatic Species Information Programme, FAO Fisheries and Aquaculture Department, Rome.

Pauley, G.B., B. Van Der Raay, and D. Troutt. 1988. Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Northwest) - Pacific Oyster. National Wetlands Research Center, US Fish and Wildlife Service, Slidell, LA.

Prince William Sound Regional Citizens Advisory Council. 2004. Non-Indigenous Species of Concern for Alaska: Pacific (Japanese) Oyster.