McMahon,

If western Washington is isolated, then yes, my example is somewhate isolated. (Those of us who deal with this issue routinely don't feel it's quite so isolated.) However, that's only in the sense that Chambers Creek hatchery steelhead are the least fit for successful reproduction (all the way through to subsequent returning adults) in the natural environment. Other hatchery steelhead strains that have been studied (typically summer runs) are also less fit in the natural environment than their wild counterparts, but they are more successful in natural reproduction than Chambers Creek fish. In the fuller context, I'm not sure that the Chambers Creek example is an isolated one; it's just the most extreme example, which makes it suitable for purposes of illustrating the point.

The lower but successful natural reproduction of summer steelhead stocks has maintained and today creates the potential for recovery of bonafide viable wild steelhead populations in systems like the Methow, Okanogan, Entiat, and Wenatchee Rivers. The same is possibly true for some Snake River tributaries too, but I've never seen the data, so I don't know.

If fitness is an incorrect term, please advise me what the correct term is. I didn't get the memo indicating that "fitness" had limited application only through the phase of producing viable offspring. Which leads me to question, how truly viable are offspring if they return as adults at a rate that is statistically near zero? Thanks.

Sg