It wasn't long, though, before humankind discovered another commercial use for freshwater mussel shells. The pearly white nacre of some North American mussel species makes excellent starting nuclei for what will eventually become cultured pearls. Small blanks are cut from shells, formed into beads and tucked into oysters. Because it is an irritant, the oyster lays down a thick coating of secretions over the mussel bead. Today, the cultured pearl industry is a multimillion dollar business.
Freshwater mussels are ecologically important.
Mussels are eaten by raccoons, mink, otters, waterfowl and fish. Mussels are biological indicators of water quality because they are long-lived and relatively immobile, and they accumulate contaminants present in water and sediment that can be scientifically analyzed. Some species of mussles lure fish with a minnow replica of specialized tissue. The mussels then release tiny glochida that attach to a fish's gills, where they will metamorphose into juvenile mussels. Mussel hunt Snorkeling and scuba diving are the most common methods used to search for live freshwater mussels.