Asian clam is a small bivalve that has become an invasive species in the United States.
Its origin is in eastern Asia and Africa. Exactly when and how is arrived
in the United States is unknown.
The Asian clam does well in estuarine habitats and river beds and is
found in fresh waters throughout the United States. It has colonized areas
of the Delaware and Ohio River basins, and is found in all five Gulf states
and northern Mexico. Populations have been reported for the San Francisco
Bay, California and Chesapeake Bay, Virginia.
Adults can reach 50 mm in length. The shell has distinct rings and is
a yellow-brown color.
Immature Asian clams are free-floating and difficult to see, two factors
that have contributed to their rapid spread across the United States.
The clams have a higher tolerance to pollutants than native species, allowing
for colonization in areas that would most likely not be inhabited by native
2010 Distribution of Asiatic Clam
Much like the zebra and quagga mussels, the Asian clam is known to clog
intake pipes, damage industrial water systems, alter aquatic habitat,
and disrupt irrigation canals. There is also concern that Asian clams
compete for food with native mussels and clams.
In open systems such as the Ohio River, careful maintenance of boat and other
watercraft should be observed. All watercraft should be washed thoroughly
with HOT water. Bait buckets should never be transferred between bodies
of water. Control methods are similar to those of zebra and quagga mussels.
In closed environments, such as power plants, mechanical or chemical control
methods are used to eradicate the species.
MORE INFORMATION ON THE ASIAN CLAM