The Blue Mussel attaches to a rock face using very strong byssus threads. These byssus thread, or “beard”, are the mussels only defense sometimes using them to wrap around invasive mollusks, causing them to not be able to move and in turn not be able to eat. Also eaten by humans, starfish, seabirds, and by numerous species of predatory marine gastropods. Mussels come in female and male, reproduction occurring outside the animal. Immature mussels will “float” until they are able to attach to a rock or substrate. Mussels are bivalves, meaning filter feeders, filtering out zoo and phyto plankton for food. This makes them susceptible to red tide on the Salish Sea for, almost, all year long.