Freshwater mussels in an impacted watershed: Influences of pollution from point and non-point sources.

The Grand River watershed in a densely populated region of Ontario supports one of the richest assemblages of freshwater mussels in Canada. However, water quality in this watershed is influenced by urban development, agriculture, and industry. Mussel populations and water chemistry in the lower Grand River and the Boston Creek tributary were evaluated to determine whether point sources of pollution such as discharges of domestic wastewater and industrial effluent, and non-point sources of pollution are affecting mussel distribution and population structure.