The Asian Clam is an introduced species of freshwater clam in British Columbia that is native to China, Korea, southeastern Russia and the Ussuri Basin, but is now found throughout much of Europe and the Americas (Kirkendale and Clare 2008
). It was first reported in North America from Nanaimo, BC, in 1927, and was reported again in BC until 2008 when it was collected at Irwin Park (previously known as Humpback Valley Campgrounds) in the Sooke watershed (Kirkendale and Clare 2008). Varying sizes of clams were found, ranging from 1-5 cm (Kirkendale and Clare 2008). Investigation by these authors indicated that there was a confirmed report of this species from the confluence of Scott Creek and the Coquitlam River in the Lower Fraser Area prior to 2008, and this may indicate that it is more widespread. No date is provided for that record however and this may not represent an established population. A single collection from Stanley Park has been discovered in the Royal BC Museum, dated 1989.
Asian Clam "has a yellowish brown to black shell with concentric, evenly spaced ridges on the shell surface (INHS 1996). They are usually less than 25mm but can grow up to 50 to 65mm in length" (Global Invasive Species Database 2005). It is an invasive species that often grows in high densities where it has invaded (e.g. 12,000/m2 in Texas) and can cause damage to water intake pipes (Global Invasive Species Database 2005, Kirkendale and Clare 2008).
The Global Invasive Species Database (2005) provides the following details on this species: "Corbicula fluminea is found in lakes and streams of all sizes with silt, mud, sand, and gravel substrate (INHS 1996). They can tolerate salinities of up to 13 ppt for short periods (Aguirre and Poss 1999) and temperatures between 2 and 30 degrees Celsius, or 86 degrees Fahrenheit, (Balcom 1994). It prefers fine, clean sand, clay, and coarse sand substrates (Aguirre and Poss 1999). It is usually found in moving water because it requires high levels of dissolved oxygen. C. fluminea is generally intolerant of pollution."
This species is used as live bait and is common in the aquarium trade.
Read the USGS fact sheet for this species, which includes a US distribution map.