The "dollies" are thought to be sea-going bull trout per WDFW.
Not anymore
"Early studies described these fish as a variety of the Arctic char, while later work declared them to be a separate species. For a long time, the bull trout was considered just a localized version of the Dolly Varden. Now many fisheries scientists believe that Dolly Varden and bull trout are two distinct species that look amazingly similar.
Bull trout and Dolly Varden are difficult to distinguish from each other, even for specialists. Dolly Varden tend to have a more rounded body shape while bull trout have a larger, more flattened head and a more pronounced hook on the lower jaw. Some scientists believe that one of the distinguishing characteristics of bull trout is that they do not migrate to saltwater. However, Washington biologists have recently found bull trout in Puget Sound.
Bull trout and Dolly Varden can be distinguished from eastern brook trout by the absence of vermiculations ("worm tracks") on their back. In addition, the eastern brook trout's red spots are surrounded by blue halos. To keep things interesting, though, bull trout and brook trout have been known to spawn together. Their hybrid offspring can have features of both parents. (Hybridization can be a serious problem in some areas, resulting in the dilution or destruction of the gene pool of the native bull trout.)"
