Geoduck

Also Known As

King Clam, Elephant Clam, Gweduck, Goeduck, Goiduck

Quick Facts

Weight

Up to 7 pounds

Length

Shell typically 6 - 8 inches; siphon can be up to 3 feet

Region

Alaska, West Coast

About the Species

Geoduck (pronounced “gooey-duck”) can be found along the West Coast of the United States from Alaska to Baja California. There is both wild harvest and a growing geoduck aquaculture industry, particularly in Washington State. The majority of Washington’s geoduck farming takes place in southern Puget Sound.

Environmental Impact

Geoducks provide net environmental benefits by removing excess nutrients and improving water quality.

Feeds

Growing geoducks requires no feed – they filter phytoplankton directly from the water column.

Farming Methods

Geoducks are planted in PVC pipes on intertidal beaches until they are large enough to burrow into the sediment.

Human Health

Shellfish toxins and bacteria occur naturally in the environment and can cause foodborne illnesses. State and federal regulations require monitoring of farmed geoducks to ensure they are safe to eat.

Appearance

Geoducks are characterized by a small shell and very long siphon, or "neck."
The long “neck” has two openings at the end – one for taking in oxygen and phytoplankton and one for releasing excess water.

Biology

Geoducks are long-lived; the oldest ever recorded was 168 years old.
Geoducks burrow into the sediment about 1 foot per year to a depth of 3 feet.
In the first 3-5 years, geoducks grow to 1.5 pounds, though they make not reach maximum size, about 7 pounds, for 15 years.
Females release between 1 and 2 million eggs per spawn.

Fishery 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, US 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. //