Occurs in pools and runs of medium to large rivers. Also found in lakes. Pelagic up to 1.8 cm in length. Young feed on planktonic cladocerans, copepods, ostracods, and mites; chironomid, trichopteran and ephemeropteran larvae; and bottom ooze. Adults feed on algae, diatoms, insects, amphipods, and mollusks. May feed on salmonid eggs. Preyed upon by mergansers, osprey, eagles, and bears. Edible but not highly favored.