KUMAMOTO OYSTERS

Kumamoto oysters are a separate biological species from their close relative, the Pacific oyster.  Kumamoto oysters were accidentally introduced along with Pacific oysters from Japan in the mid-20^th century.  They have unique characteristics, which make them valuable in live shellfish markets.  Although they are good biological species, as we have shown in the papers listed below, particularly Banks et al. (1994), sperm from the Pacific oyster can successfully fertilize the eggs of the Kumamoto oyster.  This has led to inadvertent hybridization in commercial shellfish hatcheries and degradation of the desirable qualities of Kumamoto stocks.  We have been active for several decades in the recognition and prevention of such hybridization and in efforts to import new Kumamoto oyster stocks from their native range in Japan.