Although mussels have little value as human food, they hold immense ecological value. As a vital link in the food chain, they are a major food item for many animals including muskrats, otters, and raccoons. Young mussels are also eaten by ducks, wading birds, and fish. As important natural filterers, they improve water quality by straining out suspended particles and pollutants from our rivers. A single mussel can filter several gallons of water per day–ultimately making the water cleaner for human uses.

Mussels serve as good indicators of ecosystem health because they remain essentially in one place for a long time and require good water and sediment quality and physical habitat. As such, they are frequently used by biologists as “biological monitors” to indicate past and present water and sediment quality in rivers and lakes. For example, biologists can measure the amount of certain pollutants in mussel tissue to determine the type and extent of water pollution in various rivers and lakes.

Freshwater mussels are often found in aggregations called mussel beds, which can be a mile or more long and contain thousands of mussels. Adults bury themselves in the bottom sediment with a fleshy muscular foot and live by filtering algae and other food items from the water column. In the Mississippi River, many species do well near the main channel of the river where there is adequate flowing water, food, and stable substrates.

Mussel bed

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Other species occupy the soft-bottomed sediments typically found in backwaters. Live mussels and dead shells also provide habitat for a variety of aquatic insects and algae. They act like a freshwater “reef,” providing the foundation for a variety of life forms and habitat conditions suitable for other aquatic organisms.

Archeological excavation

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Archeological excavations, such as the one pictured above, uncovered many mussel shells, demonstratcing that historically, mussels were used by early Americans for food, tools, and jewelry. Today, mussels are not recommended as food for humans or domestic animals because they accumulate and store toxic contaminants in their tissues.