Tug,

I'm not sure who the genius are. I was discussing this with a tribal bio just the other day and did not have a chance to go into any detail. Color me puzzled when he said he thought the tribal case UNDER-estimated the salmon production loss by up to a factor of four. I used very general, but very available productivity values for the back-of-the-envelope estimate I posted the other day. If there are data that support a significantly higher productivity estimate, I haven't seen it.

Hypothetically more production could be realized without higher spawning escapements if the habitat is of significantly higher quality, meaning more productive than the existing accessible habitat. I don't think that is the case. The majority of salmon habitat in western WA has been degraded by forest practices at least, if not by additional anthropomorphic activities. Forest practices means large increases in stream sedimentation which reduces egg to fry survival. Back in the 1950s, WDFW estimated that as little as 20 to 25% of a Chinook or coho population was easily enough spawners to maintain population productivity. With habitat degradation in the latter half of the 20th century, it looks more like roughly 50% of a Chinook and coho population is needed for escapement to maintain a run. That appears to be directly due to the measured decrease in egg to fry survival. So it looks like the hypotheses is false, and that salmon production will not increase unless the increase in accessible habitat is accompanied by increased spawning escapement.

Sg