Aquaculture - Shellfish

Quahogs

The common hard shell clam, or quahog, is well adapted to life in the sea, particularly the sand and mud flats of the subtidal and lower intertidal zone. The northern quahog, Mercenaria mercenaria, belongs to the class Bivalvia, easily identifiable by two, somewhat rounded, hinged shells, protruding burrowing foot, and the purple or dark blue border found on the inside of the shell. The variety known as M. Mercenaria notata is widely grown in Massachusetts. It is distinguished by a chestnut brown zig-zag line of the outside of the shell. Some cultivators prefer this variant because of its faster growth rate and natural identifiability. The name Mercenaria comes from the historic use of the shell for making Indian money, or wampum. Beads made from the purple part of the quahog shell were the most valuable form of wampum.

The quahog spends most of its life (which can last for up to 20 years) buried into the sediments of the subtidal and lower intertidal zone, with its two siphons reaching just above the surface to feed and discharge wastes. It feeds by filtering phytoplankton from water that it pulls in over its gills with one siphon and then pumps it back out through the other. Quahogs reproduce in the same manner as most bivalves, by shooting vast quantities of sperm and eggs into the water. Here the eggs are fertilized and dispersed by the currents. Hard clams spawn when the water temperature reaches approximately 60 degrees F. Of the millions of eggs shot out by female clams, only a small percentage survive to maturity in an uncontrolled environment.

Quahogs typically grow up to four inches and sometimes larger. Commercially, there are three names, based on size; the littleneck (48mm valve length or 1.5 inches), the cherrystone (60mm valve length or 2 inches), and the chowder ( greater than 75mm or 3 inches or more). Some individuals can attain sizes of up to 130mm or 5 inches.

Quahogs are the preferred food of several predator species, notably green crabs, starfish, moon snails, and horseshoe crabs.

*Information found at the Massachusetts White Paper


White Paper Strategic Plan Industry Permit Assitance Technical Assistance Marketing Aquaculture Education Legislative Projects Grants Program Shellfish & Finfish	Aquaculture - Shellfish Quahogs Quahogs \| Oysters \| Soft Shell Clams \| Mussels \| Scallops \| Crayfish The common hard shell clam, or quahog, is well adapted to life in the sea, particularly the sand and mud flats of the subtidal and lower intertidal zone. The northern quahog, Mercenaria mercenaria, belongs to the class Bivalvia, easily identifiable by two, somewhat rounded, hinged shells, protruding burrowing foot, and the purple or dark blue border found on the inside of the shell. The variety known as M. Mercenaria notata is widely grown in Massachusetts. It is distinguished by a chestnut brown zig-zag line of the outside of the shell. Some cultivators prefer this variant because of its faster growth rate and natural identifiability. The name Mercenaria comes from the historic use of the shell for making Indian money, or wampum. Beads made from the purple part of the quahog shell were the most valuable form of wampum. The quahog spends most of its life (which can last for up to 20 years) buried into the sediments of the subtidal and lower intertidal zone, with its two siphons reaching just above the surface to feed and discharge wastes. It feeds by filtering phytoplankton from water that it pulls in over its gills with one siphon and then pumps it back out through the other. Quahogs reproduce in the same manner as most bivalves, by shooting vast quantities of sperm and eggs into the water. Here the eggs are fertilized and dispersed by the currents. Hard clams spawn when the water temperature reaches approximately 60 degrees F. Of the millions of eggs shot out by female clams, only a small percentage survive to maturity in an uncontrolled environment. Quahogs typically grow up to four inches and sometimes larger. Commercially, there are three names, based on size; the littleneck (48mm valve length or 1.5 inches), the cherrystone (60mm valve length or 2 inches), and the chowder ( greater than 75mm or 3 inches or more). Some individuals can attain sizes of up to 130mm or 5 inches. Quahogs are the preferred food of several predator species, notably green crabs, starfish, moon snails, and horseshoe crabs. Information found at the Massachusetts White Paper*