A Clam's Life

One of the most common aquaculture crops is the quahog, or "hard-shell" clam.  Quahogs are generally spawned at a hatchery and develop into a free-swimming larval stage, known as "spat".  In the hatchery the microscopic larva are carefully monitored and fed cultured algae.

A series of intermediate culture techniques are used to move the crop out to the field as they continue to develop.  Downwellers, upwellers and nursery trays are examples of culture techniques employed at this phase of development.

As the quahogs continue to develop, several "grow-out" technologies are employed.  Using cages, trays, or netted "raceways", clams are buried in the sediment.  Another technique is to suspend the quahogs in the water from rafts or floats using pearl nets, lantern nets, or cages.  Each of these techniques is designed to form a barrier that contains the crop and protects it from predators.

In the final "grow-out" phase the crop is placed under long stretches of netting, know as "raceways". The crop is then harvested from the sediment in the raceway using conventional equipment.