Saltwater · Northern
Mussel - California Sea
Ocean regulations can change in-season. Confirm with the 2026 Ocean Sport Fishing Guide and CDFW before you fish.
Species group
MUSSEL
Season
Open All Year Annual quarantine issued by CDPH. Biotoxin Information Line: 1-800-553-4133
Depth limit
None
Daily bag limit
10 pounds (in the shell) of California sea mussels and bay mussels in combination.
Minimum size
None
Gear restrictions
Every person while taking invertebrates which have a size limit shall carry a device which is capable of accurately measuring the minimum legal size of the species taken. In all ocean waters skin and Self Contained Underwater Breathing Apparatus (SCUBA) divers may take invertebrates as provided in this article except that in all ocean waters north of Yankee Point (Monterey Co.), SCUBA may be used only to take sea urchins, rock scallops and crabs of the genus Cancer.
Identification
The California mussel (Mytilus californianus) is a large edible mussel, a marine bivalve mollusk in the family Mytilidae. This species is native to the west coast of North America, occurring from northern Mexico to the Aleutian Islands of Alaska. California mussels are found clustered together, often in very large aggregations, on rocks in the upper intertidal zone on the open coast, where they are exposed to the strong action of the surf. The shell of this species is thick and is often 80 to 130 mm in length, sometimes larger still. The shell is blue on the outside with a heavy brown periostracum which is usually worn off except near the growing edge of the shell. The beaks of the shell are often eroded. The shell has coarse radial ribbing and irregular growth lines on the outer surface. The inner surface of the shell is blue and faintly pearly.