ABSTRACT
Watershed disturbance, beginning with the conversion of forest to other land uses, affects the physical and chemical condition of streams with inevitable consequences for stream life. Water quality concerns should extend to the entire stream ecosystem, not only because fish are an important food and economic resource, but also because the condition (health, abundance, and diversity) of aquatic biota is a reflection of the health or condition of the aquatic ecosystem as a whole. Biotic communities can serve as a measure of current stream conditions and provide a means of testing the effectiveness of watershed protection and restoration measures (Karr, 1981, 1991; Kerans and Karr, 1994; Krieger and Ross, 1993).
