Rich G -
Don't know much about the upper Sol Duc however a Dolly Varden population is found about Sol Duc Falls. It is likely that the Eastern brook was in fact a Dolly. The fish above the falls are what are called "residents", that is they spend their entire life in the headwater areas. The Sol Duc fish population is sometimes dwarfs, with adults being about 6" long. The easiest way to tell a Brookie from a Dolly is to look at the dorsal fin. On a brook there will black markings while on the Dolly Varden and bull trout the fin will be essentially clear.

A couple interest facts about Dolly Varden. Here in Washington nearly all the known populations are above anadromous barriers and appear to be resident fish while the anadromous fish in western WAshington are in fact bull trout. The Dolly Varden above Sol Duc falls are the only known spawning native char in the Quillayute system.

Tight lines
Smalma