The Eastern Oyster is an introduced species in British Columbia that is native to eastern North America (the Atlantic coast). They were first introduced to the province in 1906 in Boundary Bay and Esquimalt Harbour, where they were planted (
Carl and Guiget 1958). The introductions were not highly successful with high mortality rates but in 1917 and 1918 spat were discovered in the tidal portions of the Nicoekl and Serpentine, two muddy rivers that empty into Boundary Bay" (Carl and Guiget 1958). A population of Easter Oysters can still be found in this location today (Harbo, pers. comm. 2010).
Carl and Guiget (1958) provide the following detail on separating the Eastern Oyster from other oyster species in BC: "The Eastern Oyster is easily distinguished from the native oyster by its larger size at maturity (3 1/2 to 6 inches in length), and it may be easily separated from the Japanese species because the shell is yellowish-brown (not tinted with purple) and lacks the laminations and deep grooves of the Oriental oyster. The mantle, which lies next to the inside of the shell, has light-brown border, not a black one as in the Japanese oyster."