Critter Fun Facts: Softshell clams are common on both the Pacific and Atlantic coasts of Canada but are an invasive species in Canadian Pacific waters. These clams can grow up to 3 to 4 inches in length and reach a maximum of 1/4 pound (0.1kgs). If you are ever walking along a Canadian beach at low tide and something squirts you with water from the sand, this is a softshell clam! When they are disrupted, they shoot water from where they are buried through their siphon and into the air!
Economic: Softshell clams and clams in general are an important part of Canada's shellfish industry. In 2020, the DFO reported that 4022 metric tonnes of clams were reported as landings from fisheries that year, which generated $121109 000.
OA Impact: Negative: Sediment acidification has negative effects on burrowing. This is predicted to increase dispersal to other, potentially unfavourable habitats. However, sediment pH may influence juvenile clam abundances. However, this effect could be from sediment grain size. Future work will be needed to determine this. CO2 effects on neurophysiology (GABAA receptors) can act to mediate adaptive behaviors in juvenile marine bivalves to elevated CO2, but these behaviors may be negatively affected by elevated temperature.
Diet: Softshell Clams are suspension feeders and deposit feeders (this means they will eat almost any food in the water or the surrounding substrate).
Predators: Crabs, horseshoe crabs, diving ducks, and rays are all predators of adult clams. Juvenile clams have many more predators due to their small size and their planktonic form (softshell clams' adult form is buried and not buried in the substrate).
Habitat: Softshell clams live in the sandy intertidal zone. Clams burrow down into the substrate, some as deep as 12 inches.
Geographic Distribution:
Soft shell clams are found on the East Coast and West Coasts of Canada.
Click here to view the approximate distribution on the Map of OA Resources.
Linnaean Classification:
Kingdom: Animalia
Phylum: Mollusca
Class: Bivalvia
Subclass: Autobranchia
Infraclass: Heteroconchia
Subterclass: Euheterodonta
Superorder: Imparidentia
Order: Myida
Superfamily: Myoidea
Family: Myidae
Genus: Mya
Species: arenaria
Etymology: arenaria means sandy. Mya is probably an alteration of the Ancient Greek word for mussel. Put together the softshell clams name means something along the lines of Sandy Mussel.
Common Names: steamer clam, steamer, soft-shelled clam, softshell clam, softshell, Smooth butter clam, sand gaper, Manila clam, long-necked clam, and large-neck clam.