Crassostrea gigas

The Japanese Oyster or The Giant Pacific Oyster

Phylum Mollusca
Class Bivalvia
Order Pterioida
Family Ostreidae
Genus Crassostrea
Species gigas

Description: 25 to 30 cm long, 10 to 15 cm wide.; grayish-white to tan; shell rough, highly irregular, and fluted with concentrically curved ridges; shape can vary from long and thin to round and thick.

Habitat: Can be found near estuaries, in bays and around mudflats, at lower-tide levels.

Natural History: This large oyster is quite tolerant to lower salinities, and can be found clinging to rocks or other oyster shells. It is a filter feeder, and can live for 20 years or so. It is not a native animal of this region, it was introduced from Japan early this century. The Japanese Oyster is an important commercial shellfish species. Oyster growers import spat, or tiny oysters, to replace the harvested oysters because our Northwest waters are not warm enough for the oysters to spawn.