Manila clams are native to Japan, accidentally introduced to Canadian waters during the 1920s or 1930s. They now range from the central coast of British Columbia (particularly beaches in the bays and estuaries in Georgia Strait and the west coast of Vancouver Island) to California. They make shallow burrows in the sand, gravel or mud in the mid-intertidal zone. However, because they do not migrate after they have settled in a beach and they do not burrow deeply, they can experience increased mortality during the winter when they are exposed to frost and cold winds.
Manila clams are oval in profile, narrower at the anterior end. Colouration ranges from off-white to yellow, brown or grey; they often display strips of red, blue or black when small. The inside of the shells is white or yellow with a purple stain on the posterior margin. They have concentric rings (which can be used to determine age) and radial lines on the surface of the shells. Manila clams have separate sexes, and are broadcast spawners. They can grow to 75 centimetres and live up to 14 years.
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