All About Geoducks

Say it with us

Geoduck is pronounced goo-ee-duck. Other names for this majestic mollusk: mud duck, king clam and (translated from Chinese) elephant-trunk clam.

All About Geoducks

A well-earned name

Geoducks (Panopea generosa) are native to the west coast of North America, and their name is derived from a phrase in the Nisqually language, gʷídəq, which means “dig deep.”

The world’s largest burrowing clam

When fully mature, Puget Sound geoducks weigh, on average, a bit over two pounds. Their shells are between six and eight inches long, and their siphons (the “necks” that protrude from their shells) can be over three feet long!

All About Geoducks


The largest geoduck ever weighed and verified by the Washington Department of Fish and Wildlife was a whopping 8.16 pounds.

Old timers

Geoducks can live more than 150 years, and don’t reach their full size until they’re 15 years old.

All About Geoducks

Deep diggers

True to their name, geoducks are generally found buried two to three feet deep in mud, sand or gravel on Puget Sound beaches (by comparison, Manila clams are usually two to four inches underground).

Don’t pull!

If you’re lucky enough to see a geoduck siphon on a Puget Sound beach, touch it gently—if you can even do so fast enough before the geoduck retracts it. Pulling on the siphon will break it and kill the animal. Fast fact: it’s illegal in Washington state to possess only the siphon of a geoduck.

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