Hard Clam/Northern Quahog

About the Species

U.S. farmed hard clams are a smart seafood choice because they are sustainably grown and harvested under U.S. state and federal regulations.

Appearance

• Adult hard clams are just less than 3 inches, but can reach up to 5 inches.
• The shell is thick, grey to white in color, and has outer concentric growth rings.
• The inside of the shell is white with violet markings.
• Some hatchery raised clams have dark, zigzag stripes across the shell known as “notata”.

Biology

• Are of the shellfish family. Like oysters, mussels, and scallops they are bivalve mollusks, and have a hinged shell.
• Clams have slow growth rates and can live 12-20 years on average, and up to 40 years.
• Adults are sessile – they stay in one place – and inhabit both intertidal and sub-tidal areas.
• Clams burrow into the sediment, leaving only their siphons expose to feed.
• Hard clams prefer saline water and cannot survive if the salt content is too low.
• Each female can produce between 1 and 5 million eggs during a spawning event.

Management

• Permitting for shellfish aquaculture is governed by federal, state and local governments.
• The federal agencies involved are NOAA, the Army Corps of Engineers, Fish & Wildlife Service, U.S. Department of Agriculture, the Environmental Protection Agency, the Food and Drug Administration, the Bureau of Ocean Energy Management, and the Coast Guard.
• Shellfish farms must adhere to federal regulations including those in the Magnuson-Stevens Fishery Conservation & Management Act, the Endangered Species Act, the National Environmental Policy Act and the Clean Water Act.
• Information on shellfish aquaculture permitting can be found in the Shellfish Growers Guide.
• A variety of shellfish aquaculture tools, including maps and models, are available to coastal managers.