California Mussels

California mussel shells have a thick (body) profile and the anterior end, part closed to the rock that it is attached to(umbo) is sharply pointed.  It has strong radial ribs and irregular transverse, across the body, growth lines.  Parts of shell are often eroded.  The top (periostracum) is usually heavy and blue-black.

Exterior of the California Mussel with Byssal threads

The shell interior is blue-gray, may be slightly iridescent.  It attachs to rocks by byssal threads.

Interior of the California Mussel

Life Cycle

Mussels are either male or female  and fertilization occurs in the water. In general, bivalves (mussels, clams, oysters, and scallops) can live 20 to 30 years and grow to be 3- 5 inches long.

In the mating season the female mussel squirts millions of eggs into the water. As the male passes, he sends out many sperms. Few of the mussels grow up because most of them are eaten. Hairy cilia help the baby  mussels to swim. On the second day of its life the mussel has already grown a tiny yellow shell. When the mussel grows, it loses its cilia. The mussel floats for a month trying to find a place to settle. A bubble of air inside its body keeps it floating. 

The baby mussel is only 1/15 inches long when it settles to the bottom of the ocean. It attaches to the sea floor with strong threads called byssus. Byssus are rope-like strands that tie the mussel to the ocean floor. Byssus have little tiny tips on them with a substance that is like plastic cement. It is almost impossible to pull the mussel off the rock, but sometimes these threads break and the mussel has to grow new byssus and attach to the rock again. Mussels spend most of their lives in one spot.Cilia is hair-like strands that cover the mussel's body. The cilia take the water to the gills and the mussel gets oxygen from the water. The cilia also take the plankton to its mouth

Home

Although called the California Mussel they can be found from Alaska all the way down to Baja California, Mexico  in the low to mid-inter tidal area  in bays (rocky shore), estuary, wharf pilings, sea walls, exposed rocky shore, kelp forest, protected rocky shore from 0-24 m/0-80 ft. 

Habitat of California Mussels
Mussels thrive in areas of high wave energy and are usually found in dense mats referred to as “mussel beds.” 

Mussel Beds in Laguna Beach

Food

Mussels eat tiny plankton and small shreds of plants and decaying material.

Note: The video below shows Quagga Mussels Feeding found in Lake Michigan. Quagga Mussels are fresh water mussels. California Mussels are salt water mussels but they all eat there food in a similar way

Predators are Sea Gulls, Sea Otters, Sea stars and Humans

For those of you that like Mussels, like myself there are many delicious ways to serve and eat them. 

Conservation Status

Like all tide pools they are a delicate Eco-system but are doing good.

Fast Facts

• Scientific Name: Mytilus Californianus 
•  Mytilidae: Smooth-shelled marine mussels
• Californianus: California
• To collect enough food to survive, a mussel filters two to three quarts (about two to three liters) of water an hour!
• A California mussel grows to full size in about three years
• Mussels rarely move after settling. They live attached to rocks or  other suitable substrate by byssal threads, which are secreted by the foot. 
• California mussels, may reach a length of 86 mm (3.4 in.) within its first year.

Sources

Monterey Bay Aquarium California Mussel
Sanctuary Simon-California Mussel
Sea World California Mussels
Think Quest-Mussel
Nathistoc Molluscs
Mussel Bed Image

“Live in the sunshine, swim the sea, drink the wild air.” Ralph Waldo Emerson