||Occurs in deep runs and pools of medium to large rivers, and lakes (Ref. 5723). Anadromous forms spend a considerable time of their lives at sea; non-migratory populations remain in lakes and rivers (Ref. 4779). Freshwater populations feed on planktonic crustaceans, amphipods, mollusks, insects and fishes (Ref. 4479, 6258). Among the marine fishes eaten are cottids (Myxocephalus groenlandicus, Triglops pingeli), arctic cod (Boreogadus saida), sand lance (Ammodytes spp.), snailfishes (Liparis spp.) and smaller Arctic char (Ref. 5951). Extremely sensitive to water pollution (cold water and oxygen oriented) (Ref. 2163).