Dolly Varden trout, (species Salvelinus malma), char of the family Salmonidae, found in northwestern North America and northeastern Asia. It has yellow spots on the back, reddish spots on the sides, and a white edge on the lower fins; it takes its name from that of a character in Charles Dickens’ Barnaby Rudge. It often migrates to sea, grows large and silvery, and returns to streams to spawn. A good food and game fish, it has an average size of about 0.5 to 1.8 kg (1 to 4 pounds) but may be much larger.