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Hard Shell Clam

Artwork by: Joann Wheeler 1999

Fast Facts:

Clams are searched out with bare feet.  When one is discovered the toes are curled over the clam and then drawn up against the other leg until it can be grasped and placed into a floating bucket.

Size Up to 4 inches.
Habitat Hard shell clams or "quahogs" are native to the coastal waters from the Gulf of St. Lawrence to the Gulf of Mexico. They prefer salinity ranging from 15 ppt to 32 ppt (sea water). Quahogs are commonly found in the sand and mud flats of subtidal and lower intertidal estuarine and marine environments.
Reproduction Quahogs reproduce by spawning, which is typically triggered when water temperatures reach approximately 60 F (16 C). Once the eggs are fertilized, free swimming larvae develop within a few hours. Despite their swimming abilities, they are still susceptible to currents, winds and wave action that can disperse them great distances from the site of fertilization. The larval period generally takes one to three weeks and is greatly influenced by water temperature. Larvae metamorph into the juvenile stage and resemble small adults. Juveniles are capable of crawling on the bottom sediments. Once the clam finds a suitable substrate (good food resources, low predation and low wave action), they dig into the sediments with their muscular foot. While still small, they can re-emerge and search for more suitable substrates. However, when soft shell clams become larger, the remainder of their life is spent sessile beneath the sediments. Adults do not bury deeply into sediments.
Feeding Like all bivalves, quahogs have two tubes, called siphons, that work together to strain out food particles from the water column. They filter the water for phytoplankton by pumping water in through one siphon, passing it over the gills where food particles collect and pumping it out with the other siphon.
Predators Quahogs are the preferred food for several predators including: blue crabs (Callinectes sapidus), starfish, moon snails (Family: Naticidae) and horseshoe crabs (Limulus polyphemus).
Description Quahogs are the most common clam in the Chesapeake Bay and are easily identifiable by two thick almost heart shaped hinged shells, protruding burrowing foot and the purple or dark blue border found on the inside of the shell. The hinge bears three white cardinal teeth that hold the two halves in alignment. Their siphons can be seen reaching just above the surface of the sediments for feeding and delivering wastes away from the clam. Quahogs can live up to 20 years and spend most of their lives buried in the sediments.
Other Quahog (pronounced ‘kO-"hog) comes from the Algonqin Native American language. The name Mercenaria comes from the historic use of the shell for making Native American money, or wampum. Beads that were made from the purple part of the shell were the most valuable form of wampum. "Treading" for quahogs is a favorite pastime for visitors to the lower Chesapeake Bay.  People are often confused by the different colloquial names given to hard clams. Quahogs, littlenecks, cherrystones, chowder clams and hard clams all refer to the same species. Three names are often assigned to the size of the clam for culinary and commercial purposes. "Littlenecks" (1.5 inches) and "cherrystones" (2 inches) are the preferred size for cocktail clams served raw on the half shell. "Chowder" (>3 inches) are the preferred size for clam chowder.

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