California Mussel, Mytilus californianus, is a an edible (sometimes) bivalve mollusk. He lives in the splash zone all along our coastline and most people just think of him as part of the scenery, but scientists consider him to be a "keystone species." In fact, Dr. Robert T. Paine came up with the term after studying the relationship between California Mussel and our Starfish, Pisaster ochraceus. It basically means that these two animals play critical roles in the cycle of life in our part of the world.

California Mussel attaches himself to rock with a strong adhesive called byssus by the zoologists. As a youngster, he can move by breaking old connections and creating new ones, but the process is understandably very slow. At maturity, he becomes sedentary. He likes to gather in large, dense aggregations because it helps withstand the force of the waves. Several other animals make these aggregations their home including certain snails and worms. His tough shell protects him from the elements, but some predators can get through it. Man is, of course, one of those predators, as is Oystercatcher, but the most important is Starfish.

California Mussel

California Mussel

California Mussel

California Mussel

As the waves wash over California Mussel and sometimes submerge him, he opens his shell slightly to eat a particular form of plankton. This Plankton is a minute plant that grows in the upper layers of the ocean and is too small to be seen by the human eye. A lot of the marine life cycle depends on it. The plankton, in turn, depends on clean water with just the right amounts of salinity, temperature, and nutrients. We are fortunate that the waters off our shore are rich in these nutrients. California Mussel filters about sixteen gallons of water every day in his quest for his veggies. (Pollution can, of course, change the balance and kill the plankton. That will starve the animals that depend on it, which, in turn, impacts those further up the chain of life including California Mussel and Whale.)

California Mussel has long been an important food source for man. Native Americans all along the California coast ate enormous amounts and there are shell mounds to prove it. Today, most mussels that you buy in the store are Blue Mussel, a cousin of California Mussel, and the government prohibits collection of "wild mussels" during certain times of the year for health reasons. On very rare occasions you will find an imperfect pearl in California Mussel, but don't get your hopes up - they are not valuable.

California mussel can be poisonous during certain periods (not just red tide).
Best check with the experts before collecting them for the table.